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  • 1
    Electronic Resource
    Electronic Resource
    Synthesis and thermal studies of bisitaconimide-methacrylic acid copolymers (1987)
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 152 (1987), S. 21-31 
    Details
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Ein Copolymeres aus 3,3′-Bisitaconimido-m,m′-diphenylsulfon und Methacrylsäure wurde in einer radikalischen Polymerisation hergestellt. Das Copolymere wurde charakterisiert und die Copolymerisationsparameter ermittelt. Die durch drei verschiedene Methoden erhaltenen Reaktivitätsverhältnisse stimmen gut überein und lassen auf ein alternierendes Copolymeres schließen. Der thermische Abbau des Bisitaconimidhomopolymeren und des Copolymeren wurden verglichen und das thermische Verhalten diskutiert. Die Aktivierungsenergien für die verschiedenen Stufen des thermischen Abbaus des Homo- und des Copolymeren wurden durch Coats-Redfarn-Diagramme ermittelt.
    Notes: A copolymer of 3,3′-bisitaconimido-m,m′-diphenyl sulfone and methacrylic acid was synthesized by free radical polymerization. The copolymer was characterized and the copolymerization parameters were evaluated. The reactivity ratios determined by three different methods were in good agreement and the values suggest an alternating copolymer. The thermal degradation of the bisitaconimide homopolymer and the copolymer were compared and the structural implications on the thermal behaviour are discussed. The activation energies for the different stages of thermal decomposition of both the homopolymer and the copolymer were evaluated from the Coats-Redfarn plots.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/apmc.1987.051520103
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  • 2
    Electronic Resource
    Electronic Resource
    Saponification kinetic study of mica-acrylonitrile graft copolymers (1988)
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 157 (1988), S. 177-187 
    Details
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die Kinetik der alkalischen Hydrolyse von Glimmer-Acrylnitril-Pfropfcopolymeren wurde untersucht. Die Abhängigkeit des Verseifungsgrades von der Alkalikonzentration und der Hydrolysezeit wurde bestimmt. Chemische und spektroskopische Techniken wurden zur Bestimmung des Hydrolysemechanismus herangezogen.
    Notes: Kinetics of alkaline hydrolysis of mica-acrylonitrile graft copolymers was studied. The dependence of alkali concentration and the time of hydrolysis on the degree of saponification was determined. Chemical and spectroscopical techniques were used to determine the mechanism of hydrolysis.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/apmc.1988.051570114
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  • 3
    Electronic Resource
    Electronic Resource
    7-Amino-actinomycin D complexes with deoxynucleotides as models for the binding of the drug to DNA (1979)
    New York : Wiley-Blackwell
    Biopolymers 18 (1979), S. 1749-1762 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Fluorescence, CD, absorption, and 1H-nmr studies are reported for complexes of 7-amino-actinomycin D with deoxydinucleotides, deoxytetranucleotides, and poly(dG-dC)· poly(dG-dC). The optical spectra for the 7-amino-actinomycin D complex with pdG-dC, pdG-dC-dG-dC and pdC-dG-dC-dG are similar in shape to the 7-amino-actinomycin D complex with either DNA or poly(dG-dC). The changes in the 1H chemical shifts of the 7-amino-actinomycin D and the pdG-dC resonances that accompany complex formation show that 7-amino-actinomycin D forms a minature intercalated complex with two pdG-dC molecules. The magnitudes of the induced chemical shifts for the 7-amino-actinomycin D complex formation with pdG-dC are similar to, but slightly different from, the induced chemical shifts which are obtained when actinomycin D forms a minature intercalated complex with two pdG-dC molecules. The pdN-dG dinucleotides (N = C, A, or T) form stacked complexes with 7-amino-actinomycin D. The presence of the 7-amino-group results in a larger dimerization constant (in aqueous solution) for 7-amino-actinomycin D [KD(6°C) = 4.4 × 103M-1], as compared to actinomycin D [KD(6°C) = 1.7 × 103M-1]; the chemical shifts which accompany dimer formation indicate that the chromophores stack in an inverted manner. Intercalation of 7-amino-actinomycin D into minature double helices, as well as into calf thymus DNA, poly(dG-dC)·poly(dG-dC), and poly(dA-dC)·poly(dG-dT), results in an enhancement of the relative fluorescence intensity and a shift in both the absorbance and corrected emission spectra.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.1979.360180712
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  • 4
    Electronic Resource
    Electronic Resource
    Oxygen-ascorbic acid-Copper(II) initiating system. A kinetic study of the polymerisation of methyl acrylate in aqueous medium (1982)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 183 (1982), S. 905-913 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Polymerisation of methyl acrylate (MA) initiated by O2-ascorbic acid (AA)-Cu2+ system was studied in aqueous medium at 40°C. The rate of polymerisation Rp, was found to increase, remain constant, and then decrease with increasing [Cu2+]. Rp was found to depend on [Cu2+]0,6, [AA]0, [O2]0,6, and [MA]1,3 in the increasing region, on [Cu2+]0, [AA]0, [O2]0,6, and [MA]1,6 in the constant region and on [Cu2+]-0,9, [AA]0, [O2]0,7, and [MA]2,0 in the decreasing region. Rate laws were derived assuming a plausible reaction mechanism for the different regions. Rp increased with ionic strength and decreased with [H2SO4,]. An initial increase, then steady state followed by a decrease in rate with temperature was noticed in the range 25 - 55°C. kp/kt1/2 values were calculated and compared with literature values. Chain lengths were determined viscometrically.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1982.021830414
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  • 5
    Electronic Resource
    Electronic Resource
    Collagen-Poly(methyl methacrylate) graft copolymers: Effect of aqueous organic solvent system and salts on copolymer composition (1974)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 175 (1974), S. 729-737 
    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: Kollagen-Polymethylmethacrylat (PMMA)-Pfropfcopolymere wurden in einer Anzahl wäßrig-organischer Lösungsmittelsysteme und in Gegenwart neutraler Salze mit Cerammoniumnitrat als Initiator dargestellt. Die Zusammensetzung der Kollagen-Methylmethacrylat-Pfropfcopolymere wurde durch Hydrolyse der Kollagen-Hauptkette und Bestimmung der Molekulargewichte der gepfropften PMMA-Zweige ermittelt. In Wasser/Methanol als Medium für die Pfropfreaktion zeigten die Molekulargewichte der PMMA-Zweige ein Maximum bei einer Methanol-Konzentration von 25%, um dann mit steigender Methanol-Konzentration wieder abzufallen. Wenn auch der beobachtete Prozentgehalt an Pfropfung mit steigender Konzentration von Methanol einen scharfen Abfall aufwies, blieb die Anzahl von Pfropfstellen mehr oder weniger konstant und war ungefähr dieselbe wie diejenige, die in wäßriger Lösung bestimmt wurde. Andere wäßrig-organische Lösungsmittel-Systeme lieferten Ketten, die mehr Pfropfungen aufwiesen als jene, die in Wasser dargestellt wurden und niedrigeres Molekulargewicht besitzen. Es wurde gezeigt, daß Sulfat- und Chlorid-Anionen einen größeren Einfluß auf die Erniedrigung der Pfropfstellen ausüben als Nitrate.
    Notes: Collagen-poly(methyl methacrylate) (PMMA) graft copolymers were prepared in a number of aqueous/organic solvent systems and in the presence of neutral salts using ceric ammonium nitrate as initiator. The composition of the collagen-methyl methacrylate graft copolymers was studied by hydrolyzing the collagen backbone and measuring the molecular weights of the grafted PMMA branches. In water/methanol grafting media the molecular weights of the PMMA branches showed a maximum at a methanol concentration of 25% and then decreased with further increase in methanol concentration. Even though the percent grafting registered a sharp fall with increasing concentration of methanol, the number of grafting sites remained more or less constant and was almost the same as that obtained in aqueous medium. Other aqueous/organic solvent systems gave more grafted chains than those prepared in water alone, and these were of lower molecular weight. Anions such as sulphate and chloride were found to have more influence than nitrate in decreasing the number of grafting sites.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1974.021750303
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  • 6
    Electronic Resource
    Electronic Resource
    Grafting on polyester fibers (1975)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 19 (1975), S. 461-480 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Acrylic acid (AA) and acrylonitrile (AN) were used to carry out grafting on polyester (PE) fibers using the techniques of initiation by γ-radiation as well as benzoyl peroxide. The nature of the grafted fiber substance was found to be the same, irrespective of the grafting technique. Extent of grafting depended upon the time, concentration of the initiator, and the monomer as well as on the irradiation dose. The increase in the moisture regain was directly proportional to the amount of graft in the fiber. AA grafted fibers were rendered more hydrophilic than AN grafted fibers for equivalent amount of grafts. Considerable improvement in dyeability of the PE fibers was possible through grafting. About 50% to 100% improvement with disperse dyes was observed in case of PE fibers containing 22.4% and 9.0% graft of AA and AN, respectively. Intense fast dyeing with direct and basic (cationic) dyes was also possible, and the dye content was proportional to the extent of graft introduced in the fiber. The CN groups were reduced to NH2 groups in the AN graft on the fiber. In this way, deep, fast, and bright dyeing was obtained with reactive dyes. Electrokinetic studies were carried out on the grafted fibers. With the increased amount of AA graft, the maxima in the zeta potential curve shifted toward higher acidic pH as greater amounts of alkali was utilized by the —COOH groups in the graft. In this respect, CN groups were less sensitive due to their lesser polarity as compared to the carboxylic groups. It was observed from surface charge density (S.C.D.) studies that the effective surface area of the fiber decreased with the increase in the amount of graft, particularly in case of AN graft. Surface conductivity (S.C.) studies revealed that with increase in the number of polar groups (—COOH) on the surface of the fiber, the S.C. increased with the increase in the amount of AA graft. In case of AN grafts, the reduction in effective surface area of the fiber played a more important role than the contribution by the CN groups to surface conductivity.
    Additional Material: 17 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1975.070190212
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  • 7
    Electronic Resource
    Electronic Resource
    Grafting onto polyester fibers. II. Kinetics of grafting of acrylic acid, acrylonitrile, and vinyl acetate onto polyester fibers (1979)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 23 (1979), S. 2133-2138 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The kinetics of grafting of acrylonitrile, acrylic acid, and vinyl acetate onto polyester fiber by catalytic initiation and radiation were studied. The energy of activation determined for acrylic acid grafting by the catalytic method was 10.7 kcal/mole and that for vinyl acetate grafting by the radiation method, 11.7 kcal/mole. In the case of acrylonitrile grafting by the catalytic method, the rate of grafting decreased with increase in temperature of grafting, showing the differential behavior of the precipitating type of polymer from that of homogeneous polymerization.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1979.070230723
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  • 8
    Electronic Resource
    Electronic Resource
    Radiation induced grafting of mixed monomers onto polyester and polypropylene fibers (1987)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 33 (1987), S. 2707-2714 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Grafting of the mixture of acrylamide and acrylic acid onto polyester and polypropylene fibers and mixture of acrylic acid and methacrylic acid onto polypropylene by the radiation method are reported. It is observed that when pure acrylamide was used for grafting, the grafting extent was small, whereas when the mixture was used, the amount of acrylamide content in the copolymer was found to be more than the feed ratios. The results are explained on the basis of chain transfer mechanism. With methacrylic acid and acrylic acid mixtures, the rate of grafting decreased with the increase in the concentration of acrylic acid in the feed ratio, and this has been explained on the basis of the formation of either a 3-dimensional network structure or a highly branched structure involving backbone polymer molecules with acrylic acid, which prevents the diffusion of the monomer from the solution phase to the swollen phase.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1987.070330805
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  • 9
    Electronic Resource
    Electronic Resource
    Addition polyimides. II. Synthesis and characterization of bisitaconimide prepolymers (1989)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 37 (1989), S. 127-144 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: N,N′-bis(3,3′-itaconimidophenyl) sulfone has been synthesized by reacting itaconic anhydride with 3,3′-diamino diphenyl sulfone. The bisitaconimides and the intermediates were characterized by chemical analysis, IR, NMR, TG, and GPC. The degree of polymerization (DP) of the prepolymers of the bisitaconimide was followed by GPC and from the NMR data on vinylidene and aromatic proton ratios. The correlation between DP and intrinsic viscosity of the prepolymers was made use of to determine the Mark-Houwink constants (K and α). The thermal stability and the decomposition kinetics of the prepolymers were evaluated from TG data. The kinetic parameters, viz. energy of activation, E, and preexponential factor A, were computed using four nonisothermal integral equations, and their values are not appreciably affected by the degree of polymerization, within the range studied.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1989.070370110
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  • 10
    Electronic Resource
    Electronic Resource
    Thermally stable polymers based on addition-type imidobenzoxazoles; synthesis and characterization of polybismaleimidobenzoxazoles and polybiscitraconimidobenzoxazoles (1986)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 24 (1986), S. 1109-1132 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Four structurally different bisimidobenzoxazole monomers were synthesized, based on the reaction of two isomeric diaminobenzoxazoles, viz., 5-amino-2-(p-aminophenyl) benzoxazole and 5-amino-2-(m-aminophenyl) benzoxazole with maleic and citraconic anhydrides. The diamines were synthesized by a new route. The imides and the amic intermediates were characterized by elemental analysis, IR, NMR, and mass spectra. The imides could be thermally polymerized to crosslinked brittle polybisimidobenzoxazoles. The citraconimides polymerized at a lower temperature than the maleimide. Thermal stability of the cured resins was evaluated by TGA and was correlated to the structure of the polyimide. The polybismaleimidobenzoxazoles were stable up to about 500°C in N2, leaving 50-60% anaerobic char yield at 800°C, whereas polybiscitraconimidobenzoxazoles were stable up to 420°C. Comparison of the thermal behavior of similar polyimides based on oxydianiline revealed that incorporation of benzoxazole structure enhances the decomposition temperature, lowers the rate of decomposition, and enhances the anaerobic char yield at high temperature. Addition of diamines as chain-extending agents decreased the thermal stability of the resins without any change in the anaerobic char yield.
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1986.080240604
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