ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Studies on comblike polymers. 7. Carbon-13 NMR characterization of poly(oxiranes) containing long hydrocarbon side chains (1983)
    s.l. : American Chemical Society
    Macromolecules 16 (1983), S. 1207-1212 
    Details
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ma00241a031
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Studies on comblike polymers. 6. Tacticity of poly(octadecylethylene) by carbon-13 NMR and differential scanning calorimetry (1981)
    s.l. : American Chemical Society
    Macromolecules 14 (1981), S. 1845-1847 
    Details
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ma50007a052
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Studies on polymerizations initiated by syncatalytic systems based on aluminium organic compounds, 6Part 5: cf.6.. Comparison with isobutene polymerizations initiated by ethylaluminium dichloride or aluminium trichloride (1977)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 178 (1977), S. 2223-2234 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The results of previous studies carried out on the polymerization of isobutene initiated by diethylaluminium halides plus halogens are compared with results obtained with other syncatalytic systems such as diethylaluminium chloride (or triethylaluminium) plus hydrochloric acid (or tert-butyl chloride), as well as with results obtained with aluminium compounds such as ethylaluminium dichloride or aluminium trichloride which do not require co-initiators to initiate the polymerization of isobutene. The kinetic data indicate clearly that the polymerization of isobutene initiated by syncatalytic systems is characterized by a relatively slow initiation and by the absence of important termination reactions and of transfer with monomer. In contrast to this, the polymerizations initiated by strong Lewis acids such as ethylaluminium dichloride or aluminium trichloride show a much faster initiation and stop at incomplete conversion which indicates that at least one efficient termination reaction is operative. It is also demonstrated that this termination reaction produces at least one substance which acts as a co-initiator for the isobutene polymerization initiated by diethylaluminium halides or triethylaluminium.
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1977.021780809
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Studies on polymerizations initiated by syncatalytic systems based on aluminium organic compounds, 4Part 3: cf. 7.. Polymerization of isobutene initiated by diethylaluminium chloride and chlorine (1975)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 176 (1975), S. 2319-2337 
    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: Die durch Diäthylaluminiumchlorid + Chlor ausgelöste Polymerisation des Isobutens wurde untersucht, um den Einfluß der Konzentration der verschiedenen Reagenzien, der Temperatur und des Lösungsmittels auf die Polymerisationsgeschwindigkeit und das Molekulargewicht zu bestimmen. Kinetische Studien in Methylchlorid bei -45°C mit einer Isobutenkonzentration von 0,1 mol/1 haben gezeigt, daß die Initiierung relativ langsam verläuft, wodurch die Umsatzkurve S-förmig gestaltet wird. Die Polymerisationen von einer zweiten und von weiteren Zugaben von Isobuten verlaufen ohne Beschleunigung und viel schneller als die erste Polymerisation. Dies zeigt, daß Abbruchreaktionen unbedeutend sind.Der Polymerisationsgrad wird hauptsächlich durch Übertragungsreaktionen mit Verbindungen bestimmt, deren Konzentrationen denen der Komponenten des synkatalytischen Systems proportional sind. Ein sehr ungewöhnliches Merkmal dieses Systems ist es, daß eine Übertragungsreaktion mit dem Monomer nicht vorliegt.
    Notes: The polymerization of isobutene, initiated by diethylaluminium chloride + chlorine, was studied with the main goal of clarifying the influence of the concentration of the different reagents, the temperature, and the nature of the solvent on the rate of polymerization and on the molecular weight of the products. A kinetic study carried out in methyl chloride at -45°C and with a monomer concentration of 0,1 mol/l, has shown that the polymerization is characterized by a relatively slow initiation which gives the conversion curves an S-shape. Experiments with successive monomer additions showed that the polymerization of the second and subsequent portions of monomer occurs without acceleration and with a much higher rate. This shows that termination reactions are almost negligible.The degree of polymerization depends mainly on the transfer reactions with substances having concentrations proportional to those of the components of the syncatalytic system; transfer with monomer is absent, which is a very unusual feature.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1975.021760812
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Studies on polymerizations initiated by syncatalytic systems based on aluminium organic compounds, 7Part 6: cf.6.. Reaction mechanisms (1977)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 178 (1977), S. 2235-2248 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The polymerizations of isobutene and its copolymerizations with isoprene by syncatalytic systems consisting of an aluminium compound R2AlX (with R = alkyl and X = alkyl or halogen) and of a halogen or an interhalogen compound are initiated by the addition of a positive halogen ion to the monomer. Chlorine is the best co-initiator. Whereas in this syncatalyzed polymerization of isobutene the initiation is relatively slow and monomer transfer and termination are unimportant, in the polymerization of isobutene by AlCl3 or EtAlCl2 the initiation is very fast and there is at least one efficient termination. Our interpretation of these results includes a discussion of the different initiations and chain-breaking reactions.In the syncatalyzed polymerizations the initiation rate is governed by the relatively slow interaction of initiator and co-initiator. Since the termination reactions are relatively unimportant, second and subsequent portions of monomer polymerize completely and faster than the first. The polymerizations initiated by AlCl3 or EtAlCl2 stop at incomplete conversion because of a termination which is chlorination of the carbenium ions by the anions; the AlCl3 thus formed is complexed by the unreacted monomer.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1977.021780810
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Studies on polymerizations initiated by syncatalytic systems based on aluminium organic compounds, 3Part 2: cf.8.. Polymerization and copolymerization of isobutene initiated by diethylaluminium iodide and iodine (1975)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 176 (1975), S. 2303-2317 
    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: Im Verlauf der Untersuchungen der Polymerisation des Isobutens und seiner Copolymerisation mit Isopren durch Diäthylaluminiumjodid + Jod in Pentan, Dichlormethan und Äthylchlorid, wurde der Einfluß der Konzentration der Reagenzien und der Temperatur auf die Ausbeute und das Molekulargewicht untersucht. Bei der Homopolymerisation des Isobutens, initiiert durch Diäthylaluminiumjodid + Jod, ist die Initiierung relativ langsam und führt zu nicht-stationären Reaktionen. Die Reaktion des Initiators mit dem Co-Initiator in Abwesenheit des Monomers führt zu Produkten (wahrscheinlich Äthylaluminiumdijodid). welche eine rasche, unvollständige Polymerisation des hinzugefüglen Isobutens verursachen.
    Notes: The polymerization of isobutene and its copolymerization with isoprene, initiated by diethylaluminium iodide + iodine was studied in pentane, dichloromethane, and chloroethane, and the influence of the concentrations of the reagents and of the temperature on the copolymer yield and molecular weight was investigated. In the homopolymerization of isobutene initiated by diethylaluminium iodide+iodine the initiation is a comparatively slow process leading to non-stationary reactions. The interaction between initiator and co-initiator in the absence of monomer produces products (most probably ethylaluminium diiodide) which, on addition of monomer, cause fast, incomplete polymerization of isobutene.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1975.021760811
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Structure and properties of polymers with strongly anisometric side groups (1981)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 4 (1981), S. 223-240 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The possibility that polymers containing lath-like side chains may give rise to crystalline and / or mesomorphic structures as result of the organization of the side groups is discussed with reference to the chemical structure of both main chains and side groups for two families of polymers: 1) the comblike polymers, and 2) the polymers carrying rigid, anisotropic side groups. The role played by the presence of flexible spacers of different length connecting the organizable side groups to the polymer backbones is also discussed. A wide range of polymer structures and properties may be obtained by changing the main chain structure, the length and the flexibility of the spacers, and the nature of the organizable side groups.
    Additional Material: 23 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1981.020041981116
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Group motions in the glassy state of some substituted polystyrenes and poly(vinyl benzoates) (1966)
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-2: Polymer Physics 4 (1966), S. 789-796 
    Details
    ISSN: 0449-2978
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Mechanical damping measurements were carried out in the range of 103-105 cps and between 60°K. and the softening point on some substituted Polystyrenes and poly(vinyl benzoates) containing different substituents (methyl groups, methoxy groups, and halogen atoms) either in the ring or in the main chain. The ortho and meta ring-substituted polystyrenes do not show any secondary mechanical relaxation in the glassy state, although all the other substituted polystyrenes, exhibit a low-temperature damping peak (δ process) (which is in some way connected with ring motions) whose height and temperature location depend on nature, position, and number of substituents. Substituents in the para position of the ring or in the α position in the backbone chain shift the δ peak of the unsubstituted polystyrene towards higher temperatures; this shift is accompanied by an increase of the apparent activation energy E*. Substitution in the β position, on the contrary, does not affect the δ peak. Analogous results are obtained for substituted poly(vinyl benzoates), which exhibit, in addition, a β relaxation effect, associated with carboxyl group motions. A very good correlation is found between the values of E* and the limiting relaxation time τ for the δ relaxation of polystyrenes and poly(vinyl benzoates), similarly substituted in the ring, indicating that the δ relaxation leads to absorption curves in the mechanical relaxation spectrum which are characteristic of the structure of the aromatic side chain.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1966.160040510
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Calorimetric study of blends of poly(butylene terephthalate) and a liquid crystalline polyester (1987)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Physics 25 (1987), S. 1595-1605 
    Details
    ISSN: 0887-6266
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The thermal properties of solution-prepared blends of poly(butylene terephthalate) (PBT) and liquid crystalline poly(biphenyl-4,4′-ylene sebacate) (PB8) have been studied by differential scanning calorimetry (DSC). The smectic-to-isotropic (s → i) transition of the mesomorphic component is observed at temperatures slightly increasing with the PB8 content, in the 270-280°C range; on cooling, the mesophase formation (i → s transition) takes place at temperatures that decrease markedly with decreasing PB8 content. The temperatures of the crystal-to-smectic and smectic-to-crystal transitions of PB8 are almost invariant with blend composition. The melting and crystallization temperatures of the PBT phase decrease on increasing the content of the liquid crystalline component.These results, together with those of isothermal calorimetry of both the crystallization of the PBT component and the mesophase formation of the PB8 component of the blends, indicate that the two polymers are not immiscible in the isotropic state. In this latter state, however, the two polyesters undergo transesterification, which can be followed through changes in the DSC scans. The effect of the thermal history on the properties of the blends has been studied with particular attention. Both the dynamic and the isothermal calorimetric measurements provide evidence of an increase of the degree of crystallinity of PBT on addition of the liquid crystalline component up to about 35-50% by weight.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/polb.1987.090250803
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Studies on comb-like polymers, 4Part 3: cf.3. Calorimetric study of stereoregular and atactic poly(1-alkylethylene)s and poly(1-alkylethylene oxide)s (1980)
    Basel : Wiley-Blackwell
    Die Makromolekulare Chemie, Rapid Communications 1 (1980), S. 557-562 
    Details
    ISSN: 0173-2803
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/marc.1980.030010907
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...