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  • 1
    Publication Date: 1969-02-01
    Print ISSN: 0014-3057
    Electronic ISSN: 1873-1945
    Topics: Chemistry and Pharmacology , Physics
    Published by Elsevier
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  • 2
    Publication Date: 1969-02-01
    Print ISSN: 0014-3057
    Electronic ISSN: 1873-1945
    Topics: Chemistry and Pharmacology , Physics
    Published by Elsevier
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Polymer bulletin 28 (1992), S. 95-101 
    ISSN: 1436-2449
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary The glass transition behavior of poly(diethylene glycol-co-succinic acid) (DEGSA) and its complexes obtained in the reaction with MgO have been investigated. The number average molar mass ( $$\bar M_N $$ ) of the DEG-SA samples prior to complexation was determined by titration of the terminal COOH groups. The glass transition temperature (Tg) was measured as a function of molar mass and Mg2+ ion content. The dependence of Tg on $$\bar M_N $$ obeyed the Fox-Flory relationship. Addition of increasing amounts of MgO to DEG-SA led to a gradual increase in Tg, and a decrease in the heat capacity change (Δcp). This behavior is associated with complex formation between COO-and Mg2+. The decrease in Δcp is a result of ion-ion and to a lesser extent ion-dipole interactions which lower chain mobility. The common limiting Tg value for the three DEG-SA samples at an Mg2+/COO- ratio of ca. 0.5 approaches Tg,∞, which is the corresponding Tg of a polymer of infinite molar mass.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Journal of thermal analysis and calorimetry 18 (1980), S. 235-246 
    ISSN: 1572-8943
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Poly-(butandiol-1,4-adipat) und Poly-(diethylenglycolsuccinat) polyester und ihre «ionisierten» Derivate — mit Mg2+ — und Zn2+-Ionengehalt in verschiedenen stöchiometrischen Verhältnissen zu den endständigen COOH-Gruppen der Polyester — wurden im Derivatographen untersucht. Die thermische Zersetzung der metallhaltigen Polyester unterscheidet sich wesentlich von nicht-ionisierten Polyestern. Diese Unterschiede sind mit den sich wiederholenden chemischen Einheiten der Polyester und der chemischen Beschaffenheit der Metallionen verbunden, und proportional dem Anteil derselben. Es wird eine Erklärung des katalytischen Effekts der Metallionen auf den Zersetzungsvorgang der Polyester gegeben.
    Abstract: Резюме С помощью дериватогр афа была исследованы полиэфиры полибутан диол-1,4адипиновой кислоты и полидиэтил енгликоль янтарной к ислоты и их «ионные»производны е, содержащие ионы Mg2+ и Zn2+ р азличного стехиометрического состава относительн о концевых СООН групп п олиэфиров. Установле но, что термическое разложе ние металлосодержащ их полиэфиров значител ьно отличается от раз ложения «неионных» полиэфир ов. Эти различия обуслов лены химически повто ряющейся цепью полиэфиров и хи мической пррпдой ионов металл а и зависит от количес тва последних. Представл ено объяснение каталитического дей ствия ионов металла н а процесс разложения полиэфир ов.
    Notes: Abstract Poly-(butanediol-1,4-adipate) and poly-(diethyleneglycol-succinate) polyesters and their “ionized” derivatives, containing Mg2+ and Zn2+ ions with different stoichiometric ratios to the chain-end COOH groups of the polyesters have been investigated by derivatograph. The thermal decompositions of the metal-containing polyesters differ significantly from those of the unionized polyesters. These differences are connected with the chemical repeating unit of the polyesters and the chemical nature of the metal ions, and proportional to the amount of the latter. An explanation is given of the catalytic effect of metal ions on the process of decomposition of the polyesters.
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  • 5
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 18 (1980), S. 2803-2810 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: This article was written for the purpose of investigating the mechanisms of reactions between unsaturated polyester resins and base anhydridelike metal oxides (CaO, MgO, ZnO) which cause an increase in viscosity. As a model system ethyl-hydrogen-succinate (ESH) and ZnO were reacted in CCl4 and complexes that contained Zn-hydroxocarboxylate units took an essential part in this reaction. Solubility measurements of the model compounds and infrared (IR) spectra of the reaction products led to the conclusion that further molecular associates were formed from the mixed metal-hydroxocarboxylate complex by the carbonyl oxygens of ester groups, which resulted in end products of polymeric structure. It is suggested by IR spectroscopical analogies between the model compounds and reaction products of an adipic acid/butanediol-1,4 polyester with ZnO that similar reactions can account for the polyesters as well.
    Additional Material: 4 Ill.
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  • 6
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Rheological properties of coordination polymers formed in the reaction of low-molecular-weight (about 1000) polyesters with MgO were studied. The melt viscosity and activation energy of viscous flow were measured as functions of Mg content and temperature. Rheological behavior was discussed in view of the chemical structure of these systems and correlated with qualitative and quantitative conditions of the coordination bonds. Melts of Mg complexes of amorphous and semicrystalline polyesters showed identical rheological results.
    Additional Material: 6 Ill.
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  • 7
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2225-2236 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An increase in viscosity of reaction mixtures of low molecular mass, COOH, and alcoholic OH-terminated polyesters with MgO is considerably reduced by the presence of diols in the system. This effect is analogous with that described for the presence of water. Joint presence of water and diol results in an additive effect. The mechanism of this effect can be interpreted by coordination chemistry. In this system both diol and water saturate the coordination sphere of Mg2+ ion (as ligands). Consequently, the coordination of donor groups of polyester (terminal OH and ester carbonyl groups) is suppressed by reducing the extent of linking the polyester molecules with coordination bonds; that is, the average molecular mass of the system. Moreover, coordination of low-molecular ligands modifies the final molecular structure that occurs in the system. In addition, some kinetic effects are revealed in the process because the system is diffusion-controlled by the ever-increasing viscosity. This effect is also favorable to the coordination of low molecular mass ligands. All of these factors lead to a reduction in the increase of viscosity in the present system.
    Additional Material: 6 Ill.
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  • 8
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyester molecules containing free carboxyl end-groups react with MgO and ZnO as polydendate ligands to form donor-acceptor complexes, followed by the increase in molecular weight of the original polyester. The role of water in these coordination reactions was studied. It was demonstrated that the water can catalyze the reactions by promoting an ionization effect. In some case it can coordinate to the metal compound and effectively compete with the other ligands present.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In some cases metal dicarboxylates can be considered as polymers. Formation of crystalline or amorphous polymer depends on the type and ratio of the metal ion to the carboxylate ligand and on the preparation conditions. The “polymer salt” synthesized by the reaction of ZnO and maleic acid shows special feature due to the cis configuration of the dicarboxylic acid. The polymer prepared in a water medium has a fibrillar morphology with a helical structure which is changed by heat treatment: a molecular rearrangement takes place which leads finally to amorphous polymer. The reaction of ZnO and fumaric acid (trans configuration) results in monocrystals containing crystal water or, after heat treatment, in powderlike polymer.
    Additional Material: 19 Ill.
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  • 10
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Physics 34 (1996), S. 277-282 
    ISSN: 0887-6266
    Keywords: coordination polymers ; melt viscosity ; thixotropy ; polyesters ; telechelic networks ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The viscosity behavior of polymer melts containing complexes formed between the neutralized polyester poly(diethylene glycol-co-succinic acid) and Zn acetates is discussed. The melt viscosity of these materials increases with the concentration of metal ions, and shows strong thixotropy and shear thinning. This behavior is attributed to the formation of coordination bonds between the electron donor groups within the polyester chain, and empty coordination sites of the various Zn acetate salts. The coordination complexes were obtained in situ in the polymer melt, which contains well-dispersed ZnO, by adding an equimolar amount of CH3COOH. It is proposed that the shear applied to the polymer melt destroys the polar network of the coordination polymer at a rate that is greater than the rate of reformation of the coordination bonds for the sample returning back to equilibrium, following a shear deformation. © 1996 John Wiley & Sons, Inc.
    Additional Material: 4 Ill.
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