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  • Articles  (188)
  • Polymer and Materials Science  (188)
  • Aircraft Propulsion and Power
  • Life and Medical Sciences
  • 1985-1989
  • 1975-1979
  • 1950-1954  (188)
  • 1953  (188)
  • Physics  (188)
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  • Articles  (188)
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  • Polymer and Materials Science  (188)
  • Aircraft Propulsion and Power
  • Life and Medical Sciences
  • Chemistry  (188)
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  • 1985-1989
  • 1975-1979
  • 1950-1954  (188)
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  • 1
    Electronic Resource
    Electronic Resource
    Fitting of polymer distributions of molecular weight by the method of moments (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 1-18 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: As an alternative method to fractionating the polymer into portions of different molecular weight, in order to obtain the distribution of molecular weights, the method of fitting by statistical moments is proposed. It is shown how from a knowledge of differen order, utilising the inequalities between such averages and their relation to the dispersion of molecular weight, estimates of the distribution function can be obtained: (A) under the assumption of a standard form for the distribution function; (B) without such an assumption, but building up the approximation from a standard form as the norm function and its derivatives; (C) without using any standard form of distribution at all. Numerical examples of the fitting procedures accompany the exposition.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1953.120100101
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  • 2
    Electronic Resource
    Electronic Resource
    Étude expèrimentale de la lumière diffusée par des bâtonnets anisotropesPresented at the Symposium of the Commission on Macromolecules of the International Union of Chemistry, Strasbourg, June 9-11, 1952. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 29-37 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Assuming an anisotropic rod model for the molecule, the results of the light scattering theory was applied to suspension of tobacco mosaic virus. The anisotropy δ of the rod was first determined by extrapolating at zero diffusion angle the depolarization factor pv. A value of 0.3 was also found for δ, which seems to be high as compared with that received from flow birefringence experiments (δ = +0.1). By comparing the angular repartitions of the different components with the theoretical curves, one obtains a satisfactory agreement, taking a rod-length L = 2300 A, which agrees very well with the theory. An identical analysis, applied to thymonucleic acid S VIII, as prepared by Schwander in NaCl M neutral solution, gives the following values: \documentclass{article}\pagestyle{empty}\begin{document}${\rm \delta } = - 0,15{\rm et}L = 2000\mathop {\rm A}\limits^{\rm o}$\end{document}
    Notes: Nous avons appliaué à l'étude de suspensions de virus de la mosaïque du tabac les résultats de la théorie de la diffusion par des bâtonnets anisotropes. Dans ce but on détermine d'abord l'anisotropie δ du bâtonnet en extrapolant à angle de diffusion nul le facteur de dépolarisation ρv. On trouve ainsi δ = 0,3, valeur un peu forte comparée à celle déduite des expériences de biréfringence d'écoulement (δ = +0,1). Enfin comparant les répartitions angulaires des différentes composantes avec la courbe théorique, on obtient un accord trés satisfaisant en prenant pour longueur des bâtonnets L = 2300 Å, ce qui constitue un bonne vérification de la théorie précitée.La même analyse appliquée à l'acide thymonucleique S VIII préparé par Schwander en solution NaCl 1M neutre conduit aux valeurs: \documentclass{article}\pagestyle{empty}\begin{document}${\rm \delta } = - 0,15{\rm et}L = 2000\mathop {\rm A}\limits^{\rm o}$\end{document}
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1953.120100103
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  • 3
    Electronic Resource
    Electronic Resource
    The changes induced in sodium desoxyribonucleate by dilute acidPresented at the Symposium of the Commission on Macromolecules of the International Union of Chemistry, Strasbourg, June 9-11, 1952. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 109-119 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Light scattering and viscosity studies have been made on solutions of sodium desoxyribonucleate in 0.2 M NaCl adjusted to pH values of 6.5, 3.0, and 2.6 by dialysis in order to prevent contact with more concentrated acid. It is found that the molecular weight (7,700,000) is the same under these three conditions and remains so when the acid solutions are adjusted to pH 6.5. Upon lowering the pH the molecular size decreases due to increased coiling, but returns to its original value upon reneutralization. At pH 2.6 the mean radius of the molecule is less than half the pH 6.5 value. It is argued that these observations invalidate the existing evidence for degradation or disaggregation accompanying the appearance of new titratable groups. However, it is likely that most of the amino groups have not been titrated at pH 2.6 at the ionic strength employed here. Consequently the possibility remains that the stability at pH 2.6 is a consequence of a hydrogen-bonded structure that is still largely intact.
    Additional Material: 4 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100110
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  • 4
    Electronic Resource
    Electronic Resource
    Cellulose acetate plastics. VIVIAN STANNETT. Temple press, london 1950. 325 pp., 30 shillings net. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 128-128 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1953.120100116
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  • 5
    Electronic Resource
    Electronic Resource
    The structure of branched polymers of diallyl phthalate (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 489-498 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The complete characterization of a branched polymer involves many factors, the most difficult to assess being the average number of elementary linear portions, or branches, of which the polymer is composed, the degree of polymerization of the branches and the extent of cyclic structure formation. A method of analysis of branched polymers is proposed which should be applicable to polymers of any polyfunctional monomer the unsaturated groups of which are separated by saponifiable links. The method is based on the measurement of degree of polymerization and residual unsaturation of the polymer followed by saponification and determination of degree of polymerization of the resulting polymer, and involves the assumptions that branching in the polymer occurs only by the sharing of a monomer unit by two or more linear portions or branches depending on the number of double bonds in the monomer and also that the average degree of polymerization of the branches remains unchanged by the saponification treatment. Evidence from experiments on the saponification and re-esterification of poly(allyl acetate) and poly(allyl benzoate) indicates, that, in the case of diallyl esters, the above conditions are satisfied. The technique was therefore applied to three polymers of diallyl phthalate, and in each case the average number of chains and degree of polymerization of the chains were estimated. Evidence of considerable extents of cyclic structure formation was found, each individual branch in the polymers consisting of approximately fourteen diallyl phthalate units, six of which are doubly reacted. It is suggested that the existence of extensive formation of cyclic structures may be partly responsible for the poor correlation of predicted with actual degrees of conversion at gelation in polymerizations involving multifunctional monomers.
    Additional Material: 4 Tab.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100506
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  • 6
    Electronic Resource
    Electronic Resource
    Ultraviolet absorption spectra of polyamides (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 510-512 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100510
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  • 7
    Electronic Resource
    Electronic Resource
    A new phenomenon in flow birefringence of solutions of macromolecular substances (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 543-550 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Measurements on flow birefringence of solutions of polyvinyl chloride in cyclohexanone revealed that the angle of orientation increases with decreasing concentration of the solution. That this surprising effect was not due to constructional or experimental errors was demonstrated by results obtained with polystyrene, which were in agreement with literature data.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1953.120100604
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  • 8
    Electronic Resource
    Electronic Resource
    Calibrage de la diffusion lumineusePresented at the Symposium of the Commission on Macromolecules of the International Union of Pure and Applied Chemistry, Strasbourg, June 9-11, 1952. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 551-557 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: The transmission method was used for calibration of light scattering. It was verified that the refraction corrections are practically n2 for the scattered light; the incident beam intensity through the cell must be empirically corrected for the refraction, due to some divergence of the primary beam of light. With this method of calibration, we obtain for Rayleigh's ration in the case of benzene at 20°C. and at a wave length of 4358 A, R = (48.4 ± 1.5)10-6cm.-1. For dissymetry measurements in the commercial semioctagonal “Pyrocell” cell, some total reflections are present for solutions where the refractive index is equal or higher than 1.41; these reflections can be easily avoided by putting an absorbing glass on the rear of the cell. On the other hand, a dissymetry correction is given for the Fresnel reflections, which are formed when the light beam emerges normally, to the wall of the cell.
    Notes: Nous utilisons la méthode de transmission pour calibrer la diffusion lumineuse. Nous vérifions en utilisant des solutions d'indices de réfraction différents que la correction de réfraction est pratiquement n2 pour l'intensité diffusée, l'intensité incidente à travers la cellule devant être corrigée empiriquement pour une réfraction due à la légère divergence du faisceau primaire. A partir de ce calibrage, nous obtenons pour le rapport de Rayleigh du benzène à 20°C. et pour λ 4358 A. R = (48,4 ± 1,5)10-6 cm.-1. Pour les mesures de dissymétrie dans la cellule commerciale semioctogonale “Pyrocell,” nous montrons la présence de réflexions totales pour les solutions d'indice de réfraction ≥ 1,41, réflexions qui peuvent être éliminées aisément en plaçant un verre absorbant dansle fond de la cellule. D'autre part, nous calculons la correction à apporter à la dissymétrie du fait des réflexions de Fresnel quand le faisceau lumineux émerge normalement à la paroi de la cellule.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1953.120100605
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  • 9
    Electronic Resource
    Electronic Resource
    Attempted fractionation of GR-S by means of selective gelation in the latex (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 591-593 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Tab.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100610
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  • 10
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    Errata (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 594-594 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1953.120100611
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  • 11
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    Microbial decomposition of cellulose. R. G. H. Siu. Reinhold, New York, 1951. xi + 531 pp., $10.00. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 596-596 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
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    URL: http://dx.doi.org/10.1002/pol.1953.120100614
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  • 12
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    Copolymerization of isobutylene and styrene at low temperatures in the presence of friedel-crafts catalystsPresented in part at the 12th International Congress of Pure and Applied Chemistry, New York, September, 1951. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 21-36 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Isobutylene and styrene were copolymerized at low temperatures, in methyl chloride solution, in the presence of aluminum chloride. The temperature was varied from -30 to -94°C., and the monomer/solvent ratio, the ratio of monomers, and the catalyst concentration were varied over a considerable range. The copolymerization equation was found to be applicable to the data, and the reactivity ratios were determined for various experimental conditions. For an “open” system in which the volume steadily increases during the course of polymerization, it is shown that the copolymerization equation is formally identical to that of Mayo and Lewis, except that concentrations are replaced by amounts of the reacting species. The temperature coefficients of the reactivity ratios in the present system are compared with those for free-radical systems; some important differences are noted. The reactivity ratios of isobutylene and styrene in the present system are greatly increased under conditions of turbulent agitation. A procedure for the compositional fractionation of the copolymers is described. The results are interpreted in terms of the copolymer chain structure; they appear to admit the postulate that the reactivity ratios and corresponding propagation rate constants are functions of chain length.
    Additional Material: 7 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120110102
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  • 13
    Electronic Resource
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    A method for studying crosslinking in addition polymerizationTaken from the M. S. Thesis submitted by Murray Berdick to the graduate faculty of the Polytechnic Institute of Brooklyn; presented before the Division of Polymer Chemistry, American Chemical Society, Atlantic City, September, 1952. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 61-70 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Vinyl acetate has been copolymerized with small amounts of the diallyl ester of dithiodiglycolic acid (DADT). A method has been devised for the reduction of the disulfide crosslinks to sulfhydryl groups by means of thioglycolic acid under mild conditions, thereby enabling the recovery of the primary molecules of the original polymers. The method has been applied both to soluble copolymers (made with the lowest concentrations of DADT) and to insoluble space-network copolymers (made with slightly higher concentrations of DADT). The polymers have been characterized before and after reduction by viscosity determinations. The reduction process had only a negligible effect on the viscosity of poly(vinyl acetate). The rate of reduction was diffusion controlled not only in the case of the gels, but apparently also in cases where soluble polymers were made with amounts of DADT less than necessary for gelation at high conversion. The DADT acted not only as a crosslinking agent, but also as a chain transfer agent. The method is suggested as potentially useful in developing the theory of three dimensional polymerization, and in studying the properties of space-network polymers.
    Additional Material: 2 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120110106
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  • 14
    Electronic Resource
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    Copolymers of 2-vinylpyridine, methyl acrylate, and dichlorostyrene: Polymerization and properties in solution (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 127-138 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Copolymerization studies have been made on the three two-component systems formed by the monomers methyl acrylate, 2-vinylpyridine, and dichlorostyrene, and values of the monomer reactivity ratios were determined. Terpolymers were prepared from mixtures of these same monomers, and their compositions were compared with those predicted from the kinetic data for the copolymerizations. Measurements of dissymmetry of scattered light, molecular weight, and viscosity were made on solutions in acetic acid and in methyl ethyl ketone of a terpolymer containing 37 mole per cent methyl acrylate, 47 mole per cent 2-vinylpyridine, and 16 mole per cent dichlorostyrene. The molecular weight of the terpolymer is essentially the same in the two solvents but the polymer chain is more extended in acetic acid than in methyl ethyl ketone. In nitromethane solutions of the terpolymer the ηsp/c values increase sharply with decreasing concentration. This increase is eliminated if the solutions also contain 0.01 mole per liter of a substituted quaternary ammonium iodide. These facts indicate that the polymer behaves as a polyelectrolyte in nitromethane, presumably because of reaction between the aci-form of the solvent and the vinylpyridine groups.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1953.120110203
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  • 15
    Electronic Resource
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    Benzoyl peroxide initiated polymerization kinetics of vinyl monomers in various solvents (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 525-542 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Initial rates of polymerization in the presence of benzoyl peroxide as initiator have been determined for methyl methacrylate, vinyl acetate, and vinyl chloride in order to determine the order of reaction with respect to the monomer concentration. In the case of methyl methacrylate, the order of reaction is 1 if benzene is used as solvent; with tert-butylbenzene, the order of reaction is more complex, and can be interpreted by a “complex” formation mechanism (Mark-Josefowitz) or by cage effect (Matheson). In the case of vinyl chloride and vinyl acetate in the presence, respectively, of ethyl chloride and ethyl acetate as solvent, the order of reaction has been evaluated to 3/2 vs. monomer concentration. On the contrary, addition of benzene, even in small quantities, produces a strong decrease in rate of polymerization in the case of vinyl acetate, and makes it illusory to determine the order of reaction at high monomer concentrations. Preliminary results using azo-bis-isobutyronitrile as initiator for vinyl acetate with benzene as solvent have shown that the considerable influence exerted by benzene in the previous case cannot be attributed to a difference of rate of decomposition of the peroxide only. The results are interpretd by the mechanism of chain-transfer reactions on the solvent, with formation of radicals from which the relative stability is different from that of the growing chains.
    Additional Material: 10 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100603
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  • 16
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    Polymer news (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 558-558 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
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    URL: http://dx.doi.org/10.1002/pol.1953.120100606
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  • 17
    Electronic Resource
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    Polycondensation of six-membered lactones (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 587-591 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 8 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100609
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  • 18
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    Notes on the statistics of polymer chains (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 559-576 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The configurations of flexible macromolecules are discussed with particular emphasis on some problems arising in the theory of the volume effect. The main points considered are: (1) the relationship between the Kuhn statistical chain element and the carbon bond length; (2) the assumption that a polymer chain is equivalent to a collection of independent beads normally distributed with respect to the center of gravity (“Gaussian gas” model); (3) the distribution of segments of a polymer chain with respect to the center of gravity; (4) the theory of the execluded volume for plane models of a polymer molecule; (5) the relationship between the excluded volume and the local density of polymer segments; (6) the influence of the solvent on the excluded volume; (7) polymer configurations and viscosity.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100607
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  • 19
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    Résines alkydes-polyesters. J. Bourry, Dunod, Paris, France, 1952. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 595-595 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
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    URL: http://dx.doi.org/10.1002/pol.1953.120100613
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  • 20
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    Gutta. II. Interconversion of alpha and beta forms (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 307-323 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The gutta isolated from chicle has been demonstrated to be structurally identical with trans-polyisoprene from gutta percha and balata but has a molecular weight of 16,000-18,000, about one-half that of the latter two polymers. Its ease of purification and marked crystalline behaviour suggested its use in a study of gutta polymorphism.The α-and β-forms of chicle gutta were prepared and their identities were established by means of x-ray diffraction measurements and melting properties. The degree of crystallinity and internal molecular strain were shown to affect the melting points of the two forms of gutta through wide ranges. Interconversions of α-and β-guttas were effected by means of heat conditioning, solution and reprecipitation, melting and resolidification, and treatment of the gutta with nonsolvents. Dilatometric data were used to describe the change of specific volume when β-gutta was converted to α-gutta in a conditioning bath as the temperature was increased stepwise from 30°C. to 80°C. at the rate of 1°C. per hour. The discontinuous, saw-toothed nature of the specific volume vs. time curve was rationalized on a basis of reactions involving changes in degree of molecular order and relief of strain within the gutta. The curve suggested the following gross reactions: 30-36°C., thermal expansion of β-gutta of low crystallinity; 36-52°C., increase in degree of crystallinity of β-gutta; 52-60°C., melting of β-gutta; 60-64°C., transition of β- to α-gutta; 64-72°C., melting of α-gutta; 72-80°C., thermal expansion of molten gutta. α-Gutta, in the melted condition, was shown to undergo a transition, above 72°C., to a form whose stereo identity has not yet been established. The rate of transition from β-to α-gutta at temperatures at which α-is the stable form, appeared to be hastened in the presence of certain liquids.
    Additional Material: 6 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120110403
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  • 21
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    Viscosity characteristics of polyalkyl methacrylate solutions (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 379-380 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120110407
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  • 22
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    Molecular distribution in condensation polymers (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 424-424 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
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    URL: http://dx.doi.org/10.1002/pol.1953.120110504
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  • 23
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    Mechanism of the crystallization of high polymersCommunication No. 219 of Rubber-Stichting. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 385-398 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: In this article a conception of the mechanism of crystallization is given, on the basis of which, it is suggested the origin of spherulites might be explained. A tentative explanation of several related phenomena is based on the new concept. Crystallites are conceived to be small collections of strongly oriented polymer which, on fusing, exhibit marked shrinking in the direction of orientation. Particles of amorphous material therefore stretch out in a certain direction during crystallization, as the result of which there is substantial contraction in the other directions. This is termed “auto-orientation.” As the growing crystallite has to be fed from surrounding material, an orienation is initiated in the latter at right angles to the first crystallite. As a result of this orientation, crystallites are formed there which are oriented Perpendicular to the first crystallite. In their turn, these crystallites induce orientation in the surroundings and in this way crystallization becomes autocatalytic in character. Spherulites owe their origin to the fact that the various sectors in a symmetrical spherical order mutually cancel out their stretching and shrinking tendencies. In highly crystalline polymers with rapid nuclear formation there first comes into existence numerous radomly oriented nuclei which proliferate to small crystallites. Wherever these small crystallites come to be arranged in a suitable position, their relative tensions will be cancelled out and they will grow into a spherulite. Simultaneously small crystallites which are in an unfavorable position will be consumed by the growing spherulite, or else oriented in the correct direction and incorporated. As spherulites commonly measure from 10 to 50 microns, compensation between the tensions of the various sectors has to take place at long distance. At higher temperatures, compensation is as a rule found at short distances, i.e., crystallites which are at right angles to each other are in close proximity. Therefore “spherulites” varying individually come into existence as the crystallites are subject to other influences in addition to auto-orientation. At very low temperatures the primary small crystallites are too stable to develop into spherulites. The mechanism of crystallization as thus conceived implies that the melting point of a polymer depends not only upon the dimensions and perfection of the crystallites, but also upon the specific arrangement of the crystallites, i. e., the degree in which they stabilize each other by a mutual compensation of tensions. It also helps to explain the following facts which have been noted in experiments performed with natural rubber: (1) The typical S-shape of the crystallization curve and the constancy of the product of induction period and maximum rate of crystallization. (2) The fact that natural rubber always crystallizes under nonequilibrium conditions. (3) The failure of rubber in latex to crystallize and the fact that the rate of crystallization in films produced from latex is poorly reproducible.
    Additional Material: 13 Ill.
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    A simple and inexpensive osmometer. The molecular weight of 1:3 vinyltoluene-styrene copolymer fractions (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 447-454 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A simple and inexpensive instrument for measuring the osmotic pressure of polymer solutions has been designed. It consists of two 1-mm. I. D. Pyrex capillary tubes sealed into a flanged Pyrex sleeve, which is ground to fit snugly into a 19 × 60 mm. roundbased Alundum Thimble of medium porosity. A regenerated cellulose membrane is cast over the Alundum thimble, and the entire assembly is sealed in a test tube containing the polymer solution to be examined. This osmometer offers several unique advantages over others in current use. Its low cost and compact size permit inexpensive simultaneous measurement of many polymer solutions.A 1:3 copolymer of vinyltoluene and styrene monomers was separated into 24 cuts by fractional precipitation. On the basis of viscosity data these cuts were combined into 14 fractions. They were in the order of decreasing molecular weight, and infrared analysis indicated a uniform distribution of the ring methyl groups among the fractions. These two observations demonstrate that introduction of methyl groups into the benzene rings of a polystyrene molecule does not influence the polymer solubility appreciably.Osmotic molecular weights obtained with the Alundum thimble instruments and experimental limiting viscosity numbers gave values of 2.69 × 10-4 and 0.622 for K and α respectively in the Flory-Staudinger relation [η] = KMα. These results compare favorably with reported values for polystyrene samples prepared under similar conditions.
    Additional Material: 6 Ill.
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    Peroxides from autoxidized methyl oleate and linoleate as initiators in the preparation of butadiene-styrene synthetic rubberPresented at the meeting of the Division of Rubber Chemistry, American Chemical Society, Buffalo, New York, October 29, 1952. This paper is XIII in the series “Reactions of Fatty Materials with Oxygen,” the preceding paper being reference 1. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 487-490 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: In the dextrose-free recipe at 41°F. for the copolymerization of butadiene and styrene, using 6 × 10-4 mole of initiator per one hundred grams of monomers, methyl oleate peroxide (MOP) and methyl linoleate peroxide (MLP) gave higher polymerization rates and conversions than cumene hydroperoxide (CHP), and they gave as high rates of conversion as p-menthane hydroperoxide (PMHP). In the peroxide-dextrose recipe at 122°F., at both low and high dextrose levels, only about one-half as much MOP (1.5 × 10-4 mole) as CHP or PMHP was employed on a molar basis to achieve the same conversion and polymerization rate. In the low dextrose-redox recipe at 41°F., using 6 × 10-4 mole of initiator per one hundred grams of monomers, MLP gave slightly higher conversions than CHP or PMHP, but in the amine recipe at 41°F., MLP gave lower conversions.
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    Solubility and molecular size distribution of crosslinked polystyrene (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 513-520 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Polystyrene, in common with a number of other long chain polymers, can be crosslinked by exposure to high energy radiation, the degree of crosslinking being directly proportional to the radiation dose. Measurements were made of the solublity in benzene and toluene, as a function of degree of crosslinking. A theoretical derivation is given for the sol fractions of a long chain polymer as a function of the crosslinking index γ, assuming that the initial molecular size follows a Poisson (random probability) distribution. The relationship between s and γ is shown to be: \documentclass{article}\pagestyle{empty}\begin{document}$$ s(1 + \gamma - \gamma s)^2 = 1 $$\end{document} According to this formula a gel forms if γ〉 0.5. An extension to deal with the possibility of chain fracture is described. A comparison of the observed solubility curve with this formula, and with that given by Flory for a uniform initial molecular size shows that only the former agrees with the experimental data. Little or no chain fracture occurs due to adiation.
    Additional Material: 2 Ill.
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    Liquid polyacrylates (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 539-544 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Liquid polymers of ethyl, n-butyl, and 2-ethylhexyl acrylates were prepared using an anionic initiating system. Liquid polyethyl acrylate was tested as a plasticizer in a stabilized and unstabilized polyvinyl chloride plastisol composition. In the unstabilized composition, fused samples were obtained which were comparable in color to a di-2-ethylhexyl phthalate (DOP) plasticized polyvinyl chloride sample prepared under the same conditions. Stress-strain tests on stabilized films indicated that with liquid polyethyl acrylate as the plasticizer a film was obtained showing higher tensile strength, yet equivalent ultimate elongation as compared to a similarly prepared DOP plasticized composition.
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    Molekulargewichtsverteilung und lockerstellen in cellulosen nach versuchen von emery und cohen (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 9 (1953), S. 25-34 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Fractionation experiments of Emery and Cohen carried out of cellulose nitrates prepared from eucalyptus wood and cotton (in differents stages of depolymerisation) are exactly analysed. It shows, that there are distinct maxima of frequency at intrinsic viscosities 0,48, 0,92 and 1,35 (l/g). Hence can be followed, that there are easy decomposable bounds in the molecule of cellulose at about every 465 ± 30 units of glucose.
    Notes: Eine Genaue Analyse der Fraktionierversuche von Emery und Cohen an Cellulosenitraten aus Eukalyptusholz und Baumwolle (in verschiedenen Abbaustadien) ergibt deutliche Häfigkeitsmaxima bei den Viskositätszahlen 0,48, 0,92 und 1,35 1/g. Hieraus ist zu schließen, daß im Cellulosemolekül rascher spaltbare Bindungen im regelmäßigen Abstand von etwa 465 ± 30 Glukoseeinheiten eingebaut sind.
    Additional Material: 2 Ill.
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    Über polyvinylacetylacetate371. Mitteilung über makromolekulare Verbindungen370. Mitteilung vgl. vorstehend. (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 9 (1953), S. 52-75 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: On décrit la préparation de l'acétylacétate de polyvinyle en partant des alcools polyvinyliques et du dicétène. Ces éthers-sels nouveaux montrent les réctions de l'ester de l'acide acétylacétique monomère, mais une partie des transformations p. c. avee des amines se produit incomplètement, tandis que la réaction avee I'ammoniaque est quantitative. La réaction avee un excédant de méthyle-vinyle-cétone produit quantitativement des dérivés polymères analogues.Les acétylacétates de polyvinyle en solution concentrée dans la tétrahydro-furane se transforment en présence de la triéthyl-amine en produits à molécules-réseaux. Ces produits réticulés résultent d'une condensation des groupements aldéhyde terminaux des acétylacétates de polyvinyle avec les groupements CH2 des radicaux acétylacétates. En agissant, dans les měmes conditions, sur un alcool polyvinylique dont la plupart des groupements aldéhyde ont été réduits la transformation en produits réticulés peut ětre ralentie considérablement.
    Notes: Es wird die Darstellung von Polyvinylacetylacetaten aus Polyvinylalkoholen und Diketen beschrieben. Die neuen Ester zeigen die Reaktionen des monomeren Acetessigesters, aber ein Teil der Umsetzungen, z. B. mit aminen verläuft unvollständig, da unlösliche Produkte entstehen, während die Umsetzung mit Ammoniak vollständig erfolgt. Die Umsetzung mit einem Überschuß von Methylvinylketon führt quantitativ zu eutsprechenden polymeranalogen Derivaten.Die Polyvinylacetylacetate gehen in konzentrierter Tetrahydrofuranlösung in Anwesenhiet von Triäthylamin in vernetzte Produkte über. Diese Vernetzung beruht auf einer Kondensation der Aldehydendgruppen der Polyvinylacetylacetate mit den reaktionsfähigen CH2-Gruppen der Acetylacetatreste. Durch Verwendung eines Polyvinylalkohols, dessen Aldehydendgruppen größtenteils z. B. durch Reduktion entfernt sind, kann diese Vernetzungsreaktion unter sonst gleichen Bedingungen verlangsamt werden.
    Additional Material: 5 Ill.
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    Über die acetylierung von inclusionscellulosen374. Mitteilung über makromolekulare Verbindungen (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 9 (1953), S. 188-189 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Sous l'action de la pyridine/anhydride acétique sur les celluloses à inclusion un groupement OH est acétylé rapidement, un autre lentement et le troisième n'est acétylé que pendant quelque temps.
    Notes: Bei der Einwirkung von Pyridin-Essigsäureanhydrid auf Inclusionscellulosen wird eine Hydroxylgruppe sehr rasch acetyliert, eine zweite langsamer und eine dritte erst nach längerer Zeit.
    Additional Material: 1 Ill.
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    Über den micellaren oder makromolekularen bau der cellulosen373. Mitteilung über makromolekulare Verbindungen (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 9 (1953), S. 148-187 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: L'acétylation hétérogène des fibres naturelles et mercerisées du coton, de la ramie, du lin et du chanvre en état naturel et dégradé est étudiée en se servant de la pyridine/anhydride acétique et du benzène/anhydride acétique en présence d'acide sulfurique comme catalyseur. L'acétylation des fibres sèches mercerisées se produit lentement, tandis que les fibres à inclusion sont acétylées rapidement. Avee du benzène/anhydride acétique/acide sulfurique les celluloses à inclusion sont transformées en triacétates pendant 24 h. Les fibres naturelles sèches réagissent plus vite que les fibres mercerisées tandis que l'acétylation des fibres naturelles à inclusion se passe lentement en comparaison avec les fibres mercerisées à inclusion. L'acétylation des fibres à inclusion se passe partout d'une façon homogiène de manière que dans une fibre partiellement acétylée les groupements acétyles sont dispersés d'une façon symmétrique dans les macromolécules cellulosiques de la fibre. De l'autre côté, l'acétylation partielle des fibres dégradées sèches mène à des triacétates se trouvant à cĉté de cellulose non changée. Cette forme d'acétylation est due aux fentes se trouvant dans une fibre à cellulose dégradée.
    Notes: Die heterogene Acetylierung von mercerisierten und nativen Baumwoll-, Ramie-, Flachs- und Hanffasern in nativem und abgebautem Zustand wurde studiert, und zwar die Acetylierung mit Pyridin-Essigsäureanhydrid und mit einem Gemisch von Benzol Essigsäureanhydrid mit Schwefelsäure als Katalysator. Die Acetylierung von trockenen mercerisierten Cellulosen verläuft außerordentlich langsam, die der includierten Fasern sehr rasch, und zwar werden diese Cellulosen mit saurem Acetylierungsgemisch innerhalb eines Tages in Triacetate übergeführt. Die trockenen nativen Fasern sind reaktions-fähiger, die includierten nativen Fasern reaktionsträger als die entsprechenden mercerisierten Fasern. Die Unterschied zwischen nativen und mercerisierten Fasern wird diskutiert. Die Acetylierung der includierten Fasern erfolgt in allen Fällen homogen, so daß bei partiell acetylierten Produkten die Acetylgruppen gleichmäßig in der Faser verteilt sind. Bei der partiellen sauren Acetylierung von abgebauten trockenen Fasern erhält man dagegen Triacetate neben unveränderten Cellulosen; diese inhomogene Acetylierung hängt mit der Spaltenbildung bei den abgebauten Fasern zusammen.
    Additional Material: 25 Ill.
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    Zur frage der mikroviskosimetrie (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 10 (1953), S. 30-34 
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    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Referring to the paper from Signer and Berneis, it is shown that the capillary corrections of mikroviscosimeters may be compensated by enlarging their end-diameters rather than by enlarging their lengths.
    Notes: Im Anschluß an eine Arbeit von Signer und Berneis wird gezeigt, daß man die Steighöhenfehler bei Mikroviskosimetern besser durch Erweiterung der Kapillarenden als durch Verlängerung der Kapillaren kompensiert.
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    Fractionation of high polymers by lowering the temperature of the solution (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 11 (1953), S. 70-78 
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    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Es ist eine Methode zur Bestimmung der Verteilung der Molekulargewichte von hochpolymeren Stoffen entwickelt worden. Den Grund für diese Methode bildet die Trennung der Fraktionen durch Erniedrigung der Temperatur einer Lösung des Polymeren, die ein Fällungsmittel enthält. Wie ausgeführte Versuche-gezeigt haben, ist die Reproduzierbarkeit der Methode gut. Durch Verwendung eines konstanten Verhältnisses Lösungsmittel/Fällungsmittel in verschiedenen Fraktionierungen, ist es möglich, die Grenzviskositätszahl der erhaltenen Fraktion aus der Fällungstemperatur annähernd zu schätzen.
    Notes: A method has been developed to determine the distribution of the molecular weights of the high polymers. The basis of this method is the separation of the fractions by lowering the temperature of a solution of the polymer containing a precipitant. Experiments have shown that the reproducibility of the method is good. By using a constant solvent/precipitant ratio in different fractionations, it is possible, from the temperature of precipitation, to estimate approximately the limiting viscosity number of the fraction obtained.
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    Polyester aus cycloaliphatischen verbindungen. 10. Mitteilung über polyester1394. Mitteilung über makromolekulare Verbindungen2 (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 11 (1953), S. 85-86 
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    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
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    Über vielgliedrige, cyclische kondensationsprodukte aus terephthalaldehyd und diaminen396. Mitteilung über makromolekulare Verbindungen395. Mitteilung vgl. Chemiker-Z. 77 (1953) 679. (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 11 (1953), S. 231-232 
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    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
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    Effects of the ionizable components in cast phenoplasts (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 19-28 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The various stages employed in the production of a phenolformaldehyde cast resin are discussed. It is assumed that the chains formed during the condensation stage undergo a rearrangement upon acidification to yield roughly spherical, stabilized micelles. These micelles are concentrated by dehydration until coalescence begins. At this point the chains again rearrange and the resin becomes the continuous phase. Pronounced changes in the properties of the system are observed at this critical point. The effects produced by undercondensation, overcondensation, overdehydration, etc. are mentioned briefly. The ionizable components, by determining the interfacial pH during the curing stage, are shown to be directly related to the rate of cure, stability, color, light transmissibility, etc. of the cured casting. Transparent castings are expected only when an ionizable component of the proper refractive powers is oriented at the interface. An examination of the immediately available data provides a lead to the future changes that can be expected as aging progresses.
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    Role of depropagation reactions in the copolymerization of styrene and sulfur dioxide (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 49-62 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The rate of reaction of sulfur dioxide in styrene solutions at 60°C., with azodiisobutyronitrile as thermal catalyst, has been measured: (1) by gravimetric determination of the total rate of polymerization and analysis of the polymer formed and (2) volumetrically. An experimental arrangement for the latter method, which can be used when the partial pressure of the solvent (styrene solution) is appreciable compared to that of the solute (sulfur dioxide) is described. The kinetics of reaction conform to the mechanism previously proposed, according to which sulfur dioxide reacts in the form of a 1/1 styrene/sulfur dioxide complex C. It is shown that certain features attributable to depropagation reactions, such as the increase in the styrene content of the copolymer with decreasing styrene concentration in the reaction mixture, are much more marked at 60°C than at 20°C. By combining the rate measurements with new data on the temperature dependence of copolymer composition at elevated temperatures, it is possible to assign an approximate value to the velocity constant of a depropagation reaction involving breakage of a carbon-sulfur bond. The activation energy is estimated at 50 to 62 kJ. (12 to 15 kcals.), which is much lower than that for depropagation of a vinyl polymer; the frequency factor is about 4 X 1010 to 3 X 1012sec.-1. Some data on the composition of polymers prepared at 0° and -20°C. are appended. It is shown that the C· + C propagation step, which seems negligible at 20°C. or above, becomes of some significance at lower temperatures. Under these conditions polymers containing less than two styrene units per sulfur dioxide can be prepared.
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    Bestimmung des durchmessers geknäuelter fadenmoleküle aus lichtzersträuung und viskositätszahl: Untersuchungen an polymethylmethacrylatenPresented at the Symposium of the Commission on Macromolecules of the International Union of Chemistry, Strasbourg, June 9-11, 1952. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 79-96 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Light-scattering investigations (angular and wavelength dependence) are made on a series of fractionated polymethacrylates; the diffusion constant, sedimentation constant, and intrinsic viscosity [η] are also determined. Molecular weights and diameters of the random coils are in agreement with these methods. Dependence of the diameters of the random coil dst on molecular weight is somewhat stronger than required by Kuhn's root law (dst∼M0,6). The influence of this finding on Debye's scattering function and on the Kirkwood-Riseman viscosity equation is studied.
    Notes: Sur une serie de palyméthacrylates de méthyl fractionnés des mesures de la diffusion lumineuse (en fonction de I'angle et de la longeur d'onde) on été faites, puis la constante de diffusion, la constante de sédimentation dans I'ultrazentrifugeuse et la viscosité intrinshque [η] ont été déterminés. Les poids moléculaires et les diamètres des chaînes souples sont en concordance d'après ces méthodes. La dépendance des diametres des chaines sonples d,l du poids molkculaire est un peu plus forte que d'aprh la loi de Kuhn (dst ≃ M0.6). L'influence de cette decouverte sur la fonction de la diffusion lumineuse de mihe que sur l'equation de la viscosite de Kirkwood et Riseman est étudiée.
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    Macromolecular extension and hydrodynamic parameters in intrinsic viscosityThis work was carried out at Cornell University as part of a research program supported by the Allegany Ballistics Laboratory, Cumberland, Maryland, an establishment owned by the United States Navy and operated by Hercules Powder Company under contract NOrd 10431. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 121-123 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
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    Monomers, section II. Edited by E. R. BLOUT and H. MARK. Interscience, New York, 1951. 288 pp., £5.00. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 127-127 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
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    URL: http://dx.doi.org/10.1002/pol.1953.120100114
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    Polymerization in bulk at high pressures (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 149-155 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: In this paper an apparatus is described for polymerizing monomers in bulk up to a pressure of 10000 atmospheres and in which the polymerizing substance can be heated and the temperature of the substance measured. Styrene shows an explosive reaction at 10000 atmospheres and at about 70°C. Indene polymerizes slowly when heating at 10000 atmospheres and shows an explosive reaction at 175°C. Both compounds give a solid polymer. Crotonaldehyde heated at 10000 atmospheres gives a brittle, high-melting polymer. Coumarone and some chlorinated ethylenes carbonize when heated at 10000 atmospheres. Butyraldehyde polymerizes to a solid product which rapidly reverts to butyraldehyde.
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    Sur l'étude des mélanges de protéines au moyen de la lumière diffusèePresented at the Symposium of the Commission on Macromolecules of the International Union of Pure and Applied Chemistry, Strasbourg, June 9-11, 1952. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 167-174 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Molecular weights of lactoglobuline and trypsin, as determined at pH 6.8, agree with the data generally admitted. However the molecular weight of trypsin in 1/100 M hydrochloric acid solution in the absence of salts, is two to three times lower than the value received in buffered solution at pH 6.8. With the purpose of detecting any combination or polymerization reaction, the study of mixtures showed that no conclusion may be obtained from the values of diffused light intensity at 90° when the diffusion diagram is not rigorously symmetrical.
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    Investigation of halo patterns of amorphous polymers (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 201-211 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 5 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100208
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    Hydratation de diverses formes polymorphes de la cellulosePresented at the Symposium of the Commission on Macromolecules of the International Union of Pure and Applied Chemistry, Strasbourg, June 9-11, 1952. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 223-227 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: X-ray diffraction experiments confirm the data obtained by the blotting or centrifuging method, concerning the action of water which penetrates at different degrees in the regions of cellulose. Different forms of cellulose are more or less easily accessible. X-rays only show variations of intensity for native cellulose, but the unit cells are changed for lattices II and IIIα; the transformations are still deeper for cellulose IIIβ. X-ray diffraction does not permit determination of the stoichiometric ratios.
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    Physical chemistry of surface films. WILLIAM D. HARKINS. Reinhold, New York, 1952. 413 pp., $10.00. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 256-256 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
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    URL: http://dx.doi.org/10.1002/pol.1953.120100214
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    Rupture of rubber. I. Characteristic energy for tearing (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 291-318 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A criterion for tearing of test-pieces cut from thin sheets of a natural rubber vulcanizate, similar in form to the Griffith criterion for spreading of a crack, is formulated. This criterion involves a characteristic energy for tearing which is independent of the shape of the test-piece and of the disposition of the cut. It is shown how this characteristic energy can be found experimentally for a particular vulcanizate and used to predict the force required to tear test-pieces of the vulcanizate.
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    Determination of the leveling-off degree of polymerization of cotton and rayonPresented in part before the Division of Cellulose Chemistry at the 116th Meeting of the American Chemical Society, Atlantic City, New Jersey, September 18-23, 1949. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 577-586 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 6 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100608
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    Molecular weight dependence of the intrinsic viscosity of polymer solutions. IIThe experimental work reported in this paper was carried out at Cornell University under sponsorship of the Government Research Program on Synthetic Rubber, Synthetic Rubber Division, Reconstruction Finance Corporation. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 37-51 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Intrinsic viscosities of polystyrene and polyisobutylene fractions in good and in “ideal” solvents have been examined from the point of view of their dependence on molecular weight. A compilation of results is presented which covers exceptionally wide ranges, from several thousand to several to million, in molecular weight. The intrinsic viscosity in an “ideal” solvent (i.e., cyclohexane at 34°C. for polystyrene, or benzene at 24° for polyisobutylene) is remarkably well fitted over the molecular weight range cited above by the relation: \documentclass{article}\pagestyle{empty}\begin{document}$$ [\eta]\Theta = KM^{1/2} $$\end{document} where K is a constant, independent of molecular weight, for a particular polymer at a given temperature. The molecular expansion factor α3 which applies in good solvents (e.g., toluene for polystyrene and cyclohexane and diisobutylene for polyisobutylene) as calculated from: \documentclass{article}\pagestyle{empty}\begin{document}$$ [\eta] = KM^{1/2} \alpha^3 $$\end{document} increases with molecular weight approximately in accordance with the relationship: \documentclass{article}\pagestyle{empty}\begin{document}$$ \alpha^5 - \alpha^3 = 2C_{M\psi 1} (1 - \Theta /T)M^{1/2} $$\end{document} However, the quantity (α5 - α3)/M1/2 changes appreciably with M in some cases. This is particularly true for molecular weights below 50,000. Results of an examination of the effect of rate of shear on the viscosity of polystyrene in benzene at 25° and in cyclohexane at 34°, and of the intrinsic viscosity-molecular weight relation for polystyrene in benzene at 25°, are reported.
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    Studies on heat deterioration of specially prepared natural rubber vulcanizatesThis work was carried out under the sponsorship of the Office of Naval, Research, Project Number NR-330-010. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 83-92 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Natural rubber has been vulcanized to varying degrees of crosslinkage through the use of decamethylene dismethyl azodicarboxylate. The effect of degree of crosslinkage on extent of heat deterioration is demonstrated. Studies are also presented on the beneficial or deleterious action on heat deterioration of various chemical agents incorporated in the free state into natural rubber vulcanizate.
    Additional Material: 7 Ill.
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    The maximum precipitation temperature of a heterogeneous polymerThis work was supported by the Office of Ordnance Research under Contract DA-19-020-ORD-1545 with the Massachusetts Institute of Technology. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 93-96 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120110109
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    Copolymerization of dienes with acrylic and methacrylic acids (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 441-442 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Tab.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100407
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    The reaction of cellulose acetate with acetic acid and waterPresented in part at the Gordon Research Conference on Polymers, A. A. A. S., July 14, 1950, and also at a meeting of the Cellulose Discussion Group, Wilmington, Delaware, April 12, 1951. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 385-423 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Reaction curves for the simplest of cellulose acetylation systems; namely, the homogeneous reaction of secondary cellulose acetates with acetic acid and water, were studied. These reactions were found to be slow and complex, consisting of two interdependent simultaneous reversible second-order processes. The faster process represented the reaction of primary hydroxyl and acetyl groups, while the slower process represented the reaction of the two secondary hydroxyl and acetyl groups. Equilibrium and rate constants and initial and final concentrations of hydroxyl and acetyl groups were calculated for the two simultaneous reactions. Equilibrium constants for the primary groups favored acetylation, while equilibrium constants for the secondary groups favored deacetylation. Final equilibrium was not affected by the presence of sulfuric acid. On the other hand, rate of reaction was increased in the presence of sulfuric acid, indicating catalysis by this reagent. The reaction mechnanism outlined above was confirmed by comparing primary hydroxyl group contents calculated from acetylation results with primary hydroxyl group contents measured by means of the tritylation reaction. Energies of reaction and energies of activation were calculated. Energies of reaction were low, indicating that equilibrium for this process is very nearly temperature independent. Energies of activation were in agreement with energies of activation for esterifications of simple alcohols, from which it was concluded that the acetylation and deacetylation of secondary cellulose acetates in homogeneous solution is but another example of general acid catalyzed esterification with carboxylic acids and general acid catalyzed hydrolysis of fatty acid esters. Degradation of the cellulose chain molecule was followed throughout these studies and energies of activation for this reaction were calculated. These energies of activation were higher than those for the acetylation reactions. It was concluded that degradation is more severe at higher temperatures for a given change in acetyl group substitution. Initial determination of equilibrium and rate constants for acetic acid acetylation of cellulose acetate has been carried out. It is suggested that through use of such procedures as tritylation analysis, which isolates the reaction of the primary groups from the secondary groups, improved values for these constants may be achieved.
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    An interesting property of certain conductive rubbers (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 447-448 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100410
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    Relation between stress relaxation and aging resistance of rubber vulcanizates. II. Effect of copper in various accelerated stocks (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 449-456 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Some details for the construction of a modulus balance and thermostat are discussed. A new dumbbell type is developed for aging tests. In four stocks containing different accelerators, the function of copper applied as stearate is investigated. In the case of Santocure, a comparatively high sensitivity is found, and the t1/2 (TB) value for aging at 70°C. represents a sensitive measure of the prooxygenic effect, whereas relaxation times at 121° showed a smaller but definite variation. With MBT boosted with DPG only a limited effect was observed. Conversely, for the thiurams, copper addition produced a marked antioxidant effect comparable with the retardation normally effected by 2PHR of ordinary antioxidants. 0.05% copper showed an antioxidant activity equivalent to the 2PHR antioxidant. Consistent results were obtained for aging, relaxation, and rate of oxidation. The factors of retardation as might be expected, however, are not quite comparable. The factor of retardation for copper alone is 4-8 units. The copper develops in the thiuram vulcanizates a strong brown color giving colored solutions upon extraction with acetone and iso-octane. As the spectrophotometric determination of the colored complex is difficult, owing to the presence of the strong absorbing ZDC, the nature of the colored complex has not yet been ascertained, but it must somehow be responsible for the inverted action of copper found here.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100501
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    Viscosity, sedimentation, diffusion, and osmotic behavior of long-chain nitrocellulose moleculesReport of a study made under the Research and Marketing Act of 1946. Presented before the Division of Cellulose Chemistry, 121st meeting, American Chemical Society, Milwaukee, Wisconsin, April, 1952. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 463-487 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Viscosity, sedimentation, diffusion, and osmotic pressure measurements in ethyl acetate are reported on four unfractionated nitrocellulose polymers containing about 13.5% nitrogen and varying in molecular weight from 0.93 to 15 x 105.Detailed viscosity determinations in buret viscometers in the concentration range 0.025 to 0.300 g./dl. and over a range of velocity gradients from about 500 to 5000 sec.-1 are presented. Viscosity data adjusted to fixed shear rates fitted closely the relation ηsp/C = [η] + a2C + a3C2. Plots of ηsp/C vs. C at different shear rates were found to diverge rapidly with increasing concentration. For the nitrate of highest molecular weight, the viscosity was strongly shear-dependent and the intrinsic viscosity appeared to vary from 52 at 3000 sec.-1 to 80 or more at 0 sec.-1. The other samples displayed these tendencies less markedly with decreasing molecular weight. Other extrapolation procedures are also discussed. The intrinsic viscosity data accumulated at 500 sec.-1 could be represented by the relation [η] = KMα; α = 0.99; the molecular weights were those obtained from sedimentation-diffusion measurements on the unfractionated nitrocelluloses. Assuming for practical purposes α = 1, then Km (\documentclass{article}\pagestyle{empty}\begin{document}$\[= \overline {{\rm DP}} /[{\rm \eta ]}\]) is found to have the value 80 ± 3. Assuming a negligible depolymerization during nitration, the analogous factors required for cupriethylenediamine and for cuprammonium were found to be 170 and 230, respectively. The effect of varying shear rate on these factors is illustrated.The sedimentation constants obtained were readily extrapolated to infinite dilution with an expanded sedimentation-concentration relation, S = S0/(1 + K2C + K′s C2). Diffusion constants were obtained following the second moment method and mathematically extrapolated to zero concentration according to Gralén. Molecular weights were computed with the Svedberg equation. Number average molecular weights were obtained osmotically.Some consideration of the data in terms of the theories of Debye-Bueche and Kirkwood-Riseman is given. It is found that both K-R's and D-B's theories predict the variation of intrinsic viscosity with molecular weight within twice the standard deviation of the observed slope from the frictional coefficient-molecular weight data. In both viscosity and sedimentation the polymer appears, therefore, to behave in an approximately equally “free draining” fashion. For the calculated intrinsic viscosity of a sample of intermediate molecular weight a reasonable value is obtained from the latter theory only; but it is not uniformly successful in predicting all [η]'s, particularly those corresponding to low molecular weights.The relation between Ks, the first interaction coefficient in sedimentation and molecular dimensions, is briefly discussed. Also considered are the interaction coefficients in viscosity, especially as regards their dependence upon velocity gradient.
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    In memoriam (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 513-514 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
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    URL: http://dx.doi.org/10.1002/pol.1953.120100601
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    Swelling properties of polystyrene crosslinked by high energy radiation (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 521-529 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Polystyrene has been crosslinked by atomic pile radiation, the degree of crosslinking being proportional to the radiation dose. The swelling properties of the crosslinked polymer have been studied as a function of degree of crosslinking γ. There is found a relationship of the form required by theory: V5/3 ∝ 1/γ, V being the volume swelling ratio. This formula fails at low degrees of crosslinking. A fuller investigation shows that a number of corrections must be applied, taking into account gel fraction, distribution of molecular weight, and crosslinking index in the gel, etc. On the assumption that the initial molecular weight follows a Poisson distribution, good agreement is obtained between the fuller theory and observed data. The number-average molecular weight is between 1.53 × 105 and 2.14 × 105. The relationship between γ and radiation dose R is also obtained, and is identical with that deduced previously by entirely different means from solubility data. Pile radiation provides a means of producing polymers with accurately known crosslinking index. The energy required to produce a crosslink in polystyrene by high energy radiation is much greater than in many other linear polymers.
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    Free diffusion with coefficient dependent on concentration (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 545-557 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: An approximate solution is obtained for the nonlinear diffusion equation in which the coefficient of diffusion is a linear function of the concentration. Methods are developed for deducing the relevant parameters from experimental data and of constructing theoretical curves from these parameters. The results are illustrated by a worked example.
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    Configuration and optical activity of vinyl polymers (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 559-566 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
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    Notes: It is obvious that the starred carbon atoms in vinyl polymers of the type exist in two distinct steric configurations which are denoted here by symbols + and -. It is shown that the existence of these configurations leads to the formation of different types of polymers; however, no simple relation correlates the optical activity of such polymers with the relative distribution of + and - configurations along the polymeric chain. The various possible structures are discussed in some detail. The kinetics of such polymerizations initiated by an optically active catalyst are treated by statistical methods.
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    GR-S fractionation by means of selective adsorptionThis investigation was carried out as a part of the research project sponsored by the Reconstruction Finance Corporation, Office of Synthetic Rubber, in connection with the Government Synthetic Rubber Program. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 583-596 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 4 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120110611
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    Polymerization of methyl methacrylate by its polymer (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 299-305 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Addition of its polymer causes methyl methacrylate to polymerize. The extent of polymerization is linear with time of reaction to at last 5% conversion at 60-90°C. The rate of polymerization is proportional to the first power of the concentration of added polymer and independent of its molecular weight. The molecular weight of the polymer formed increases with increase in reaction temperature. No polymerization caused by polymer occurred with the other polymer/monomer systems tested. The rate and nature of the initiating reaction are discussed.
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    Thermal degradation of vinyl polymers in solution. I. Degradation of polystyrene in naphthalene solution (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 353-363 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The thermal degradation of polystyrene has been studied in naphthalene solutions in high vacuum. The rates of loss of weight have been determined over a range of temperatures from 350 to 380°C., and the energy of activation has been derived. Also the decrease in intrinsic viscosity with time and the loss of weight as function of polymer concentration have been investigated. The mechanism of degradation in naphthalene solution is similar to that of the thermal bulk degradation; it consists of an initial random chain scission process due to weak links, followed by a reverse polymerization process with chain end initiation.
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    Sorption of dextran to collodion membranes (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 381-382 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 2 Tab.
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    URL: http://dx.doi.org/10.1002/pol.1953.120110408
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    Relation between rate constants, frequency factors, and activation energies in polymerization raections (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 382-384 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 2 Tab.
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    URL: http://dx.doi.org/10.1002/pol.1953.120110409
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    The electrostatic free energy of polyelectrolyte solutions. I. Randomly kinked macromolecules (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 409-423 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: (1) The electrostatic free energy of randomly kinked, ionized, macromolecules was calculated for polyelectrolyte solutions of finite ionic strenght. A detailed analysis of the charging process and the reference state of the free energy is given. The mutual electrostatic repulsion of the fixed charges on the macromolecule is the main part of the electrostatic free energy. Its calculation is based on two main assumptions: the validity of Kuhn's statistics and of Debye's approximation. (2) The electrostatic contribution per macromolecule to the free energy of the solution is found to be Fe = (v2∊2/Dh)ln {1 + (6h/κh02)}, where v is the number of charged groups per polymolecule, ∊ the unit of charge, D the dielectric constant, κ Debye's inverse radius, based on the number of free ions in solution, h the end-to-end distance of the charged molecule, and h0 the corresponding end-to-end distance in and uncharged reference state. (3) Activity coefficients of free ions in polyelectrolyte solutions have been derived from the theory. The calculated values compare favorably with the activity coefficients from measurements on Donnan distribution of salt.
    Additional Material: 2 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120110503
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    A review of rates of initiation in vinyl polymerization: Styrene and methyl methacrylate (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 471-486 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 5 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120110509
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    Kinetics of chlorotrifluoroethylene polymerizationPresented at the Chicago Meeting, American Chemical Society, September, 1950. Taken from a dissertation submitted by W. M. Thomas to the Graduate Faculty of the Polytechnic Institute of Brooklyn, in June, 1950, in partial fulfillment of the requirements of the degree of Doctor of Philosophy. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 455-470 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: An exploratory investigation of the kinetics of the polymerization of chlorotrifluoroethylene (I) has been made. Experiments were conducted in bulk, in solution in several solvents, and in the presence of several comonomers. Acetyl peroxide (II) was found to be the most effective of common initiators and was used in most of the experiments. The sealed empoule technique was employed. The bulk polymerization of I is zero order to 60-80% conversion; the rate varies as the 0.7 to 0.8 power of the acetyl peroxide concentration, and the over-all activation energy is 17 kcal./mole. The solution polymerization in benzene appears to be first order in monomer; in other solvents the order was not ascertained. The rate and activation energy in solution are solvent dependent and there appears to be an inverse relationship between the rate of polymerization of I in a solvent and the rate of decomposition of II in that solvent. The rate of decomposition of II was measured in a number of solvents and found to vary widely and to parallel, roughly, the rate of decomposition of benzoyl peroxide. The polymerization rate of I in solution is also c. 0.7 order in acetyl peroxide, but was 0.5 order in Porofor N in limited experiments. From copolymerization experiments with styrene, vinyl acetate and methyl methacrylate values of Q of 0.025, 0.025, and 0.016, and of e of 1.4, 2.0, 1.4, respectively, were inferred, in the Q-e scheme of Alfrey and Price. These results above are discussed in the light of polymerization theory.
    Additional Material: 5 Ill.
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    Rates and activation energies of thermal degradation of styrene and acrylate polymers in a vacuumThis work was performed as a part of the research project sponsored by the Reconstruction Finance Corporation, Office of Synthetic Rubber, in connection with the Government Synthetic Rubber Program. This paper was presented at the 122nd meeting of the American Chemical Society in Atlantic City, September 14 to 19, 1952. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 491-506 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A study was made of rates and activation energies of thermal degradation of polymeta-methylstyrene, poly-alpha-deuterostyrene, poly-alpha-methylstyrene, and hydrogenated polystyrene, in the styrene type of polymers; and of two methyl methacrylates and one methyl acrylate, in the acrylate type of polymers. This study was carried out in the temperature range 240-355°C., by measuring rates of loss of weight of the samples, due to volatilization, by means of a very sensitive tungsten spring balance enclosed in a vacuum. The samples were limited to 5-6 mg. to avoid spattering. The activation energies were obtained by plotting the logarithms of the initial rates, against the inverse of absolute temperature. The styrene polymers, except hydrogenated polystyrene, degrade thermally chiefly into monomeric type molecules. The activation energy of these polymers is about the same as for polystyrene, which is 58 kcal. In the case of hydrogenated polystyrene, breaks in the chain occur at random, the same as in polyethylene. The activation energy is 52 kcal. Polymethyl methacrylate, like the styrene polymers, breaks mostly at the radical chain ends, yielding the monomer. The activation energy is 33 kcal. for a benzoyl peroxide polymerized, 150,000 MW polymer and 55 kcal. for a thermally polymerized, 5,100,000 MW polymer. Polymethyl acrylate follows a mechanism of random breaking of the chains, and the activation energy is 37 kcal.
    Additional Material: 8 Ill.
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    Polymeric chain transfer reactions. Polymerization of some vinyl monomers in the presence of vinyl polymers (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 531-537 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The polymerization of certain vinyl monomers in the presence of some vinyl polymers leads to the formation of a chemical bond between the resulting two polymers. A study of the efficiency of this graft copolymerization process under various conditions in emulsion has been made and the following conclusions drawn. An increase in the catalyst concentration and temperature of polymerization increases the efficiency, while the addition of dodecyl mercaptan decreases it. The list of the monomers used in the order of decreasing activity toward graft copolymerization is vinyl chloride, vinyl acetate,and styrene. A list of polymers in order of decreasing susceptibility to graft copolymerization is polyvinyl chloride, polyacrylonitrile, polyvinyl a cetate, and polystyrene.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120110603
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    On the calculation of molecular weight distributions from kinetic schemes (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 558-558 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1953.120110606
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    Orientation processes in synthetic crystalline polymers in terms of morphology (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 567-574 
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    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A new approach to orientation processes is proposed in terms of the morphology of crystalline polymers. Our present knowledge of the morphology of unoriented crystalline polymers is summarized, and the process of orientation is visualized as an alignment and pulling out of the submicroscopic and microscopic structural units. The various stages of this process are discussed and it is found that in this way several anomalous and hitherto unexplained orientation effects frequently described in the literature can be accounted for. The phenomenon of preferential tilt of the chains with respect to the fiber axis can now be explained in general terms. Peculiarities in the drawing-relaxation process, and the special case of perpendicular orientation, also substantiated by recent experiments, follow naturally from the new model.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120110609
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    Bemerkungen zur nomenklatur in der pektinchemie (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 10 (1953), S. 89-92 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: A proposition for a nomenclature about pectins published in german technical literature is compared with an english suggestion; it is recommanded for general adoption.
    Notes: Der in einem englischen Vorschlag gegebenen Nomenklatur über Pektine wird ein in der deutschen Fachliteratur mitgeteilter Vorschlag gegenübergestellt und zur allgemeinen Annahme empfohlen.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1953.020100107
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    Über die darstellung halogenierter pektinderivate (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 9 (1953), S. 109-115 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Water insoluble pectinic acid derivatives, which contain iodine, were produced. Experiments to substitute the OH-groups in the molecule by halogen were unsuccessful, however halogenation of the pectinic acid and its acetyl- and nitroderivatives succeeded by esterification with epoxyds, containing halogen.
    Notes: Es wurden jodhaltige wasserunlösliche Pektinderivate dargestellt. Versuche zur Substitution der OH-Gruppen im Pektinmolekül durch Halogen waren erfolglos. Jedoch gelang die Halogenierung von Pektinsäuren und ihren Acetyl- und Nitratderivaten durch Veresterung mit halogenhaltigen Epoxyden.
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    Kaltverstreckung als beispiel der analyse des verhaltens der makromolekularen stoffe mit methoden der physik (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 9 (1953), S. 97-108 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: The property „coldstretching“ is given as example, how to discuss properties of highpolymers form a pure physical standpoint. A most simple molecular model is employed, chemical constitution is only important for the quantitative values of characteristic parameters, not for the qualitative phenomenon. Coldstretching is a property of state as f. e. rubber elasticity or liquid or gasious state.Coldstretching is discussed as a phenomenon of coexistence of stretched and unstretched parts of the sample (cooperative process) and therefore may be formulated by an equation of state. But this is only accetable, when supplements by ideas of the thermodynamics of irreversible processes are employed. Thus irreversibility of coldstretching can be explained. The balance of energy for the process of stretching is formulated quantitatively.
    Notes: Am Beispiel der Kaltverstreckung wird die Methode einer Diskussion der Eigenschaften von Hochpolymeren vom physikalischen Standpunkt aus dargelegt: Man diskutiert das Verhalten an Hand eines möglichst einfachen molekularen Modeltes, während die speziellere chemische Konstitution erst in den quantitativen Werten der charakteristischen Parameter zum Ausdruck kommt. Kaltverstreckbarkeit ist ebenso wie das Kautschukelastische Verhalten eine Zustandseigenschaft, wie flüssig oder gasförmig.Insbesondere läßt sich der Vorgang als Koexistenzphänomen (kooperativer Mechanismus) in diesem Falle von noch nicht verstreckten und verstreckten Bereichen auffassen und somit durch eine Zustandsgleichung formulieren, allerdings nur unter geeingeter Erweiterung von Begriffen der klassischen Thermodynamik im Sinne der Thermodynamik der Irreversiblen Prozesses. Es bestehen Zusammenhänge dieser Erweiterungen mit der Irreversibilität des Vorganges. Die Energiebilanz der Verstreckung läßt sich aufstellen.
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    Der übergang von nativen in mercerisierte cellulosen375. Mitteilung über makromolekulare Verbindungen (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 9 (1953), S. 190-193 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: La transformation de la cellulose naturelle en cellulose mercerisée sous l'influence de la soude caustique de concentration différente est étudiée à l'aide de la vitesse d'acétylation exécutée avec de la pyridine/anhydride acétique et à l'aide d'observation du chiffre de nitration.
    Notes: Der Übergang von nativen in mercerisierte Cellulosen bei der Einwirkung von Natronlauge verschiedener Konzentration wird an der Acetylierungsgeschwindigkeit mit Pyridin-Essigsäureanhydrid und weiter an der Höhe der Nitrierungszahl verfolgt.
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    Vorschlag über die nomenklatur auf dem gebiete der makromolekularen stoffe. Nach dem englischen originalvorschlagVgl. J. Polym. Sci. 8 (1952) 257. (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 9 (1953), S. 195-220 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Der vorliegende Nomenklaturvorschlag ist im Auftrag der „Commission on Macromolecules“ der International Union of Pure and Applied Chemistry ausgearbeitet worden. Es sei ausdrücklich hervorgehoben, daß er nicht als endgültige Empfehlung gedacht ist, sondern eine Diskussionsbasis darstellen soll. Abänderungsvorschläge und kritische Bemerkungen aller Art mögen an den Unterzeichneten gerichtet werden, der diese Anregungen der „Commission on Macromolecules“ bei der nachsten Tagung in Stockholm im August 1953 vorlegen wird. Erst dort soll ein Beschluß über eine endgültige Formulierung gefalßt werden.
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    Über die einwirkung von hexamethylendiisocyanat auf benzolincludierte zellwolle377. Mitteilung über makromolekulare Verbindungen (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 10 (1953), S. 1-12 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Il est possible de faire réagir la cellulose d'un tissu de cellulose régénerée, qui a inclus du benzène, avec l'hexamethylenediisocyanate en formant des ponts diurethanes. La cellulose régénerée ainsi obtenue a après le traitement une teneur en azote qui va jusqu' à environ 3,5% ce qui correspond à une proportion de 4 mol C6H10O5 pour 1 mol diisocyanate. Le gonflement de cette cellulose régénerée a diminué de 50% environ. Elle n'est pas soluble dans du Cu(NH3)4(OH)2. Les ponts diurethanes sort resistants au lavage. En traitant les tissus, qui sont preparés avec du diisocyanate, avec l'acide formique à 85% et en faisant réagir de la soude à 10% sur les echantillons dégradés par le bisulfat de potassium, on a pu montrer que le diisocyanate avait réagit avec la cellulose en formant des ponts diurethanes.
    Notes: Cellulose eines Zellwollgewebes kann nach Verdrängung des Wassers durch Inclusion mit Benzol mit Hexamethylendiisocyanat umgesetzt werden. Die Zellwolle hatte nach der Behandlung einen Stickstoffgehalt von bis zu 3,5%, was einem Verhältnis von 4 Molen C6H10O5 zu 1 Mol Diisocyanat entspricht. Der Quellwert dieser Zellwolle ist auf ca. 50% erniedrigt und die Cellulose in Kupferhydroxyd-Ammoniak unlöslich. Die Diisocyanat-vernetzung ist waschfest. Durch Behandlung der mit Diisocyanat vernetzten Gewebe mit 85%iger Ameisensäure und der mit Kaliumbisulfat abgebauten Proben mit 10%iger Natronlauge wird gezeigt, daß das Diisocyanat unter Bildung von Diurethanbrücken mit der Cellulose reagiert.
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    Characterization of proteins by means of flocculation with propanolThis investigation was supported in part by grants from the American Cancer Society, (INSTR 23 E) and from the National Cencer Institute of the National Institutes of Health, U. S. Health Service (C-1785). (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 10 (1953), S. 78-88 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Es wurde gefunden, daß Proteine in Lösungen durch Flockung mit variierenden Konzentrationen an Propanol charakterisiert werden können (bei konstanter Konzentration des Proteins, konstantem PH und gleicher Temperatur). Die Trübung in den Mischungen unter den obengenannten Bedingungen ist von der Konzentration des Propanols abhängig, und verschiedene Proteine zeigten unterschiedliche Flockungskurven. Lysozym, die Albumine vom Blutserum des Menschen oder Ochsen, sowie Eieralbumin hatten einfache Trübungskurven mit stark ansteigenden Trübungswerten bei hohen Konzentrationen des Propanols, wenn die Koagulation bei einem geeigneten PH-Wert der Mischungen ausgeführt wurde. Die Kurven der γ-Globuline hatten mindestens ein Maximum, die Bence-Jones-Proteine ein oder zwei Maxima. Das zweite Trübungsmaximum der Bence-Jones-Proteine wurde in den Mischungen mit 15-20% Propanol, meistens nur bei Zimmertemperatur oder bei 37° gebildet. Es wurde vorausgesetzt, daß die Methode für die Charakterisierung pathologischer Proteine von einem gewissen Wert sein kann.
    Notes: The results of this investigation indicate that proteins in solution may be characterized by causing them to flocculate in mixtures of propanol-water in which the propanol concentration is gradually increased, and other conditions, namely PH, temperature and concentration of the protein are maintained constant. When trubidity is measured and the values are plotted against the concentration of propanol, characteristic curves are obtained which serve as diagnosis of type and homogeneity of the protein. Lysozyme, human and bovine serum albumin and egg albumin, for example, yielded simple flocculation curves; the curve obtained for γ-globulin had at least one maximum; various samples of Bence-Jones protein yielded trubidity curves which had maxima at low concentrations of propanol if the flocculation was carried out at 37°C.The method seems to be amenable to further application, particularly as a clinical method to detect abnormalities in blood proteins.
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    Versuche zur fraktionierung von proteingemischen mit polyacrylsäurenAuszugsweise vorgetragen auf dem Eiweiß-Symposium Mainz 1951. (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 10 (1953), S. 136-146 
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    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Proteins are precipitated quantitatively from aqueous acidic solutions by polyacrylic acids (P 200-400). The highpolymer substance can be removed after dissolving the symplexes at neutral PH as an insoluble Ba- or protamine-salt, whereupon the proteins are recovered in an undenatured state. The interactions of bovine serum albumin or globulin with the polylectrolyte were studied as a function of PH and polymer/protein ratio. Mixtures of both proteins and of the whole human serum proteins can be separated at PH 4,6 by gradually adding a solution of the polymer. After centrifuging, the fractions were examined by electrophoresis on filter paper. Kidney peptidase seems to be stable under the conditions of precipitation.
    Notes: Proteine lassen sich quantitativ aus wäßriger saurer Lösung durch Polyacrylsäuren (P 200-400) ausfällen. Die Symplexe lösen sich bei neutralem PH; nach Entfernung der hochpolymeren Säure als schwerlösliches Ba- oder Protaminsalz werden die Proteine undenaturiert zurückerhalten. Untersucht wurde die Abhängigkeit der ausgefällten Protein-menge vom PH und von der zugesetzten Menge an PAcs bei reinem Serum-Albumin und Globulin (Rind), sowie an Gemischen aus beiden und an Humanserum. Unter Verwendung der Papierelektrophorese konnte die bei allmählicher Zugabe des Fällungsmittels bei PH 4, 6 eintretende Fraktionierung verfolgt werden, bei der zuerst Albumin, dann die Globuline zur Abscheidung gelangen. Vorversuche mit Nierenpeptidase zeigen, daß auch hier bei der Ausfällung kein nennenswerter Aktivitätsverlust eintritt.
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    Über die größe und gestalt der amylosemoleküle382. Mitteilung Über makromolekulare Verbindungen (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 10 (1953), S. 183-184 
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    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
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    URL: http://dx.doi.org/10.1002/macp.1953.020100115
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    Über die auslösung der polymerisation ungesättigter verbindungen durch aktivierten wasserstoff (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 10 (1953), S. 202-220 
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    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: It was found in accordance with Wilson and Parravano, that Methylmethacrylate, Acrylonitril, Acrylic acid and Methylacrylate can be polymerized at a cathode in aqueous solution. The degree of efficiency of the cathode material corresponds to that of electrolytic reduction and of the overvoltage series. Cathode polymerization follows the radical mechanism and moleculare oxygen can be used as an inhibitor. - Activated hydrogen (Pd-catalyst) can start polymerization of acrylonitril and other monomers as the reducing component of redoxsystems. Under certain conditions catalytic hydrogenation and polymerization are competing reactions. - On the other hand hydrogen in statu nascendi (from sodium amalgamate) does not starts polymerization but only hydrogenation of Acrylonitril. Sodium amalgamate starts polymerization of Acrylonitril following and metalorganic mechanism.
    Notes: In Übereinstimmung mit Wilson und Parravano wurde gefunden, daß Methacrylsäuremethylester, Acrylnitril, Acrylsäure und Acrylsäuremethylester in wäßriger Lösung durch an der Kathode abgeschiedenen Wasserstoff polymerisiert werden. Die Reibenfolge der Wirksamkeit des Kathodenmaterials entspricht derjenigen der elektrolytischen Reduktion und der Überspannungsreihe. Die Kathodische Polymerisation verläuft über Radikale; sie kann durch molekularen Sauerstoff inhibiert werden. - Katalytisch erregter Wasserstoff (Pd-Katalysator) kann als Reduktionsmittel von Redoxsystemen Polymerisation von Acrylnitril und anderen Monomeren auslösen. Unter bestimmten Bedingungen erfolgen katalytische Hydrierung und Polymerisation als Konkurrenzreaktionen. - Dagegen wird durch nascierenden Wasserstoff aus Natriumamalgam neben der Hydrierung keine Polymerisation von Acrylnitril ausgelöst. Wohl aber wirkt Natriumamalgam polymerisierend auf Acrylnitril (metallorganischer Mechanismus).
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    Über die quellung resp. Inclusion der cellulose mit niederen fettsäuren386. Mitteilung über makromolekulare verbindungen (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 10 (1953), S. 254-260 
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    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: La différence entre le gonflement et l'inclusion est démontré dans le cas de l'action des acides gras sur linters. L'acide formique est capable de délier les liaisons d'hydrogène entre les macromolécules de la cellulose, c'est à dire, de gonfler la cellulose et la faire passer dans un état actif. Les acides propionique et butyrique n'en sont pas capables, mais peuvent ètre inclus dans la cellulose après un gonglement précédent avec de l'eau. Ces celluloses à inclusion montrent la même capacité de réaction comme les celluloses gonflées avec de l'acide formique. L'acide acétique se comporte d'une manière intermédiaire : habituellement, il gonfle la cellulose lentement, mais à Itempérature élevée assez vite. Puis il peut être inclue après un traitement de la cellulose avec de l'eau. La capacité de réaction des celluloses sèches et des celluloses à inclusion peut être caractérisée par la vitesse de l'acétylation avec de l'anhydride acétique dans du benzène (acide perchlorique comme catalyseur).
    Notes: Es wird der Unterschied zwischen Quellung und Inclusion bei der Einwirkung von niederen Fettsäuren auf Linters gezeigt. Die Ameisensäure vermag die Wasserstoffbrücken zwischen den Cellulose ketten zu sprengen, also die Cellulose zu quellen und in einen reaktionsfähigen Zustand überzufübren. Die Propionsäure und Buttersäure dagegen sind dazu nicht befähigt, können aber zwischen die Celluloseketten nach Vorquellung mit Wasser includiert werden. Diese „Inclusionscellulosen“ zeigen die gleiche Reaktionsfähigkeit wie die mit Ameisensäure gequollenen Cellulosen. Die Essigsäure nimmt eine Mittelstellung ein, sie quillt in der Kälte nur langsam, bei erhöhter Temperatur rasch; ferner kann sie durch Vorbehandlung der Cellulose mit Wasser includiert werden. Die Reaktionsfähigkeit der trockenen und includierten Cellulosen wird durch die Acetylierungsgeschwindigkeit mit Essigsäureanhydrid in Benzol (Überchlorsäure als Katalysator) charakterisiert.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1953.020100121
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    Synthese von makromolekeln einheitlicher größe. (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 11 (1953), S. 10-23 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: The methods by which macromolecules of uniform molecular size can be prepared are discussed. These are the synthesis step by step, the separation of polymerhomologue mixtures and the method of duplication. According to the last-named method Oligourethanes of a uniform molecular weight of about 2000 are prepared in three stages by reaction of Diisocyanates with Dioles. They are characterized by derivatives.
    Notes: Es werden die Wege zur Herstellung von Makromolekeln einheitlicher Größe diskutiert, nämlich die schrittweise Synthese, die Trennung polymerhomologer Gemische und das Duplikationsverfahren. Nach dem zuletzt genannten Verfahren werden mit Hilfe von Diisocyanaten und Diolen in 3 Stufen Oligo-urethane einheitlicher Molekelgröße bis zum Molgewicht ca. 2000 hergestellt und durch Derivate charakterisiert.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/macp.1953.020110102
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    Versuche zur darstellung von polymeren kieselsäureestern388. Mitteilung über makromolekulare Verbindungen (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 11 (1953), S. 24-50 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Attempts are described for the preparation of chain polymers by reacting dialkoxy-and diaroxy-dichlorosilane with glycols. With some diols cyclic monomeric products are formed along with polymeric esters. Other glycols form only polymers.Esters from diphenoxy-dichlorosilane are easily hydrolyzed.More resistent products are received by condensation of dicyclohexoxy-dichlorosilane with diols. Remarkably stable is the ester formed with 1,8-terpinol.
    Notes: Es wurden Versuche zur Herstellung von linearen Polymeren aus Dialkoxy- bzw. Diaryloxy-dichlorsilanen und zweiwertigen Alkoholen ausgeführt. Je nach Art des verwendeten Alkohols bilden sich - in einigen Fällen nebeneinander - cyclische monomere oder polymere Verbindungen, die jedoch nicht sehr hochmolekular sind.Die aus Diphenoxy-dichlorsilan erhaltenen Ester verseifen schon an feuchter Luft leicht. Beständiger sind die durch Kondensation von Dicyclohexoxy-dichlorsilan mit Diolen erhaltenen Produkte. Hier ist vor allem der Terpinester gegen Wasser relativ gut beständig.
    Additional Material: 1 Tab.
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    URL: http://dx.doi.org/10.1002/macp.1953.020110103
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    Über die kondensationsprodukte von äthylenthioharnstoff mit formaldehyd392. Mitteilung über makromolekulare Verbindungen (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 11 (1953), S. 81-82 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1953.020110108
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  • 86
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    Über celluloseacetate385. Mitteilung über makromolekulare verbindungen (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 10 (1953), S. 235-253 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Pour les fractions des acétates de linters1 le chiffre de viscosité Zη varie proportionnellement au degré de polymérisations dans un domaine de celui-là entre 150 et 420 déterminé par la méthode osmotique. Pour les fractions des acétates de la cellulose du linters on peut déterminer les degrés de polymérisation à l'aide de la formule (1). Ces résultats correspondent avec ceux de quelques auteurs américains.1215 Le comportement distinct des acétates de la cellulose de la pâte du bois est dû à la composition différente de celle-ei du linters.
    Notes: Bei Fraktionen von Lintersacetaten1 ändert sich in dem Bereich des osmotisch bestimmten Polymerisationsgrads 150 bis 420 die Viskositätszahl Zη proportional P. Bei Celluloseacetatfraktionen aus Linters lassen sich die Polymerisationsgrade nach der Formel (1) bestimmen. Diese Resultate stehen in guter Übereinstimmung mit denen einiger amerikanischer Autoren1215. Das etwas andersartige Verhalten von Zellstoffacetaten wird auf die unterschiedliche Zusammensetzung der Zellstoffe im Vergleich zu Linters zurückgeführt.
    Additional Material: 6 Ill.
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    URL: http://dx.doi.org/10.1002/macp.1953.020100120
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    Molekulargewicht und viskositätszahl bei polystyrolen mittlerer molekülgröße (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 11 (1953), S. 1-9 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Viscosimetric and osmotic measurements were carried out on a polymerhomologous series of fractionated polystyrenes (molecular weight between 15 000-60 000), polymerized with bromobenzoylperoxide under a variety of conditions for the determination of terminal groups. The results are then compared with those obtained by other authors.
    Notes: An einer polymerhomologen Reihe von fraktionierten Polystyrolen (Molgewichte zwischen 15 000 und 60 000), die zum Zwecke der chemischen Endgruppenbestimmung mit Brombenzoylperoxyd bei verschiedenen Bedingungen hergestellt worden waren, wurden viskosimetrische und osmotische Messungen ausgeführt. Die Ergebnisse werden mit denjenigen anderer Autoren verglichen.
    Additional Material: 3 Ill.
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    URL: http://dx.doi.org/10.1002/macp.1953.020110101
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  • 88
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    Über die bildung von kieselsäureestern aus siliciumtetrachlorid und cyanhydrinen390. Mitteilung über makromolekulare Verbindungen2 (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 11 (1953), S. 64-69 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: The preparation of silicic esters of some cyanohydrins is described.
    Notes: Es wird die Herstellung von Kieselsäureestern einiger Cyanhydrine beschrieben.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1953.020110105
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    Zur konstitution der harnstoff-formaldehyd-kondensate391. Mitteilung über makromolekulare Verbindungen (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 11 (1953), S. 79-80 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1953.020110107
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  • 90
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    Eigenschaften der polyester der acetylendicarbonsäure1. 9. Mitteilung über polyester2393. Mitteilung über makromolekulare Verbindungen3 (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 11 (1953), S. 83-84 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 3 Tab.
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    URL: http://dx.doi.org/10.1002/macp.1953.020110109
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    Zur feinstruktur von ramie (1953)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 11 (1953), S. 111-130 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Purified ramie-fibres were mechanically disintegrated. The double shadowed electron microscopic preparations revealed microfibrils with an average width of 173-203 Å and a thickness of about 30 Å. Their flattened side lays parallel to the supporting membrane. Hydrolysis in H2SO4 caused a breakage of the microfibrils into irregular „hydrolysis particles“, which consist of smaller units with 80-100 Å width and 300-1000 Å length. These probably correspond to the micellae revealed by x-ray analysis.
    Notes: Gereinigte Ramiefasern wurden auf verschiedene Weise mechanisch zertrümmert. In doppelt beschatteten elektronenmikroskopischen Präparaten wurden durchschnittliche Mikrofibrillenbreiten von 173-203 Å gemessen. Die Dicke der Mikrofibrillen, die mit ihrer Breitseite der Unterlage aufliegen, beträgt etwa 30 Å. Bei der Hydrolyse in H2SO4 werden die Fibrillen zu unregelmäßigen „Hydrolyseteilchen“ quergespalten. Diese sind aus kleineren Partikeln von 80-100 Å Breite und 300-1000 Å Länge zusammengesetzt, die wahrscheinlich den röntgenometrischen Micellen entsprechen.
    Additional Material: 3 Ill.
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    URL: http://dx.doi.org/10.1002/macp.1953.020110113
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    Shear dependence of the viscosity-concentration equation (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 123-125 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1953.120100112
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    Copolymerization of vinylsulfonic acid derivatives with butadieneThis investigation was carried out as a part of the research project sponsored by the Reconstruction Finance Corporation, Synthetic Rubber Division, in connection with the Government Synthetic Rubber Program. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 39-48 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Copolymers of vinylsulfonic acid derivatives with butadiene, isoprene, and styrene have been prepared. The evaluation of butadiene-vinylsulfonic acid ester copolymers indicates that these rubbers have good low-temperature characteristics and that the stress-strain properties of the n-butyl vinylsulfonate copolymer approach those of the standard GR-S rubber; however the oil resistance properties are poor. The stress-strain properties of the butadiene-n-hexyl vinylsulfonate copolymer are inferior to those of the n-butyl analog.
    Additional Material: 4 Tab.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100104
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    Spaltung des fibrinmoleküls mittels cupriäthylendiaminPresented at the Symposium of the Commission on Macromolecules of the International Union of Chemistry, Strasbourg; June 9-11, 1952. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 63-72 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Our investigations show that in the fibrin particle a continual distribution of the aromatic amino acids cannot be taken into account. The action of cupriaethylendiamine on fibrin splits the particle into two fractions “I” and “II.” Fraction I amounts about 75% of the molecule, is stable, insoluble in NaCl solution, and contains the whole amount of tyrosine of the fibrin molecule and 3% tryptophane. Fraction I, however showing the typical properties of a high molecular protein, cannot be brought into a fibrous form on addition of thrombin. Fraction II amounts about 15% of the molecule, in instable, soluble in NaCl-solution, contains no tyrosine, 3% tryptophane and probably much more arginine than fraction I and has the character of a proteid.
    Notes: Die Untersuchungen ergaben, dass beim Fibrin-Molekül von einer kontinuierlichen Verteilung der aromatischen Aminosäuren im allgemeinen nicht gesprochen werden kann. Die Einwirkung von Cupriäthylendiamin auf Fibrin führt zu einem Zerfall des Teilchens in zwei Fraktionen “I” und “II”. Fraktion I macht etwa 75% des Moleküls aus, ist stabil, unlöslich in NaCl-Lösung, enthält das gesamte Tyrosin des Fibrinmoleküls sowie 3% Tryptophan. Obwohl diese Fraktion noch deutlich die Eigenschaften eines hochpolymeren Eiweisskörpers zeigt, kann sie durch Thrombin nicht mehr fibrillär polymerisieren. Fraktion II dagegen macht rund 15% des Fibrins aus, ist labil, löslich in NaCl-Lösung, enthält kein Tyrosin, jedoch ebenfalls 3% Tryptophan, wahrscheinlich viel mehr Arginin als Fraktion I und trägt den Charakter eines Proteids.
    Additional Material: 4 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100106
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    Extreme ultraviolet absorption spectra of various polymersPresented at the Symposium of the Commission on Macromolecules of the International Union of Chemistry, Strasbourg, June 9-11, 1952. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 97-107 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The extreme ultraviolet absorption spectra between 1700-3000 A of a series of monomers and polymers show that, in addition to absorption due to the presence of chromophores such as phenyl rings and residual double bonds, other factors such as light scattering, orientation or polarization effects, and interaction, both intermolecular and intramolecular, are important in the observed spectra. In polymers such as polystyrene and polybutadiene, the effect due to scattering becomes appreciable (about 20-30%) at about 1700 A but the other factors do not appear to be important. In proteins, the absorption at short wavelengths is seen to be a function of absorbing chromophores as well as of residual double bond character of the polypeptide chain, of light scattering, and orientation or polarization and intramolecular effects. In other polyelectrolytes, such as polyvinylpyridinium chloride, changes in the 2000 A transition indicate that there is a degree of orientation and/or molecular interaction of the aromatic groups in these polymers.
    Additional Material: 7 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100109
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    Report on molecular-weight measurements of standard polystyrene samplesThis report, prepared by H. P. Frank and H. Mark, was submitted verbally by H. P. Frank to the Commission on Macromolecules of the International Union of Pure and Applied Chemistry at the meeting in New York on September 8, 1951. This printed version includes a few additional data and was submitted for discussion at the meeting in Strasbourg on June 9, 1952. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 129-148 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Four polystyrene samples were investigated in numerous laboratories by means of viscosimetry, osmometry, light scattering, and ultracentrifuge. The various results are compared and critically discussed. Possible explanations and suggestions for improvement are offered in those cases where considerable discrepancies occur. The results of viscosimetry and osmometry in general do not give satisfactory agreement whereas the light-scattering data, particularly in the high-molecular-weight range, and the few available ultracentrifugal results agree quite satisfactorily.
    Additional Material: 12 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100201
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    The distribution of polymer fractionsCommunication No. 1500. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 175-183 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Systems which obey the Flory-Scott equation are discussed, and it is shown that the molecular-weight distribution of increasingly small fractions taken from a polymer solution of the same initial concentration becomes constant. Means of calculating this limiting distribution of an incipient fraction are presented, and it is shown that, in a practical sense, all fractions smaller than the order of one-sixth the polymer present have nearly the same distribution. To obtain sharp fractions it is more efficacious to take a small number of cuts per stage and refractionate a number of times.
    Additional Material: 4 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100205
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    Kinetics of removal of the easily accessible fraction from cellulose fibers in acid hydrolysisPaper presented before the Section “Cell Wall Constituents,” XIIth International Congress of Pure and Applied Chemistry, New York, 1951. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 213-222 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 2 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100209
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    Intrinsic viscosity-molecular weight relationships for dextranThis work was sponsored, in part, by the Office of the Surgeon General, Department of the Army. (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 10 (1953), S. 229-240 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Intrinsic viscosities of dextrans of known branching ratio were measured in water formamide, and in a water-methanol mixture at two temperatures. Weight-average molecular weights (sedimentation equilibrium) ranged from 1.1 × 104 to 1.7 × 106. A model for the hydrolyzed dextran molecule was assumed. Using the methods of Zimm and Stockmayer, the g factor calculated from this model was compared with the g factor obtained from the intrinsic viscosity-molecular weight data through the use of the Flory-Fox theory (g = ratio of squares of radii of gyration of branched to unbranched polymer). The calculated branch lengths required to make consistent the g factors obtained by two different routes were of the same order of magnitude as those found by classical organic chemical methods for other dextran preparations. The intrinsic viscosity-molecular weight relation at 25°C. in water for linear dextran was predicted from the data. It is suggested that investigations of branched polymers of known constitution be carried out by these methods.
    Additional Material: 4 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120100211
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    An experimental study of the influence of various factors on the time dependent nature of diffusion in polymers (1953)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 97-115 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The kinetics of the sorption and desorption of methylene chloride by cellulose acetate and polystyrene have been studied by following the increase in mass of a polymer sheet suspended from a quartz spring in an atmosphere of the vapor. A tenfold change in the molecular weight of polystyrene does not alter the sorption rate, but a slight increase in rate is obtained when the molecules of this polymer are given a large unidirectional orientation in the plane of the polymer sheet. In agreement with other work, a considerable increase in both sorption and desorption rate is obtained by increasing the pressure of the solvent vapor. Previously it had been shown that a plot of the mass of sorbed vapor against the square root of the time has a slope that increases with time. It was shown that this peculiar characteristic of the sorption kinetics could not be accounted for by a purely concentration dependent diffusion coefficient, and it was suggested that it might be due either to a slow response of the diffusion coefficient to change in solvent concentrationor to the stresses set up between the swollen and unswollen parts of the polymer. Here it is shown that neither hypothesis alone will account for all the observed effects of the thickness of the polystyrene or cellulose acetate sheet upon the sorption and desorption kinetics. Sorption experiments on polymer sheet already containing some dissolved solvent do not show this peculiar characteristic of increasing slope when the concentration difference between the start and the end of the experiment is small, but when this is large very peculiar curves are obtained. The effects can be reconciled with either of the proposed mechanisms. Measurements of the changes in area during sorption and desorption have been measured on polystyrene sheet and these lend support to the strain hypothesis but also indicate that some plastic, as well as elastic, deformation of the polymer takes place during sorption.
    Additional Material: 13 Ill.
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    URL: http://dx.doi.org/10.1002/pol.1953.120110201
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