摘要:

AbstractThe structure of copolymers of acrylonitrile with itaconic acid monomethylester (1‐carboxy‐1‐carbomethoxymethyl‐ethylene) and with itaconic acid dimethylester (1‐carbomethoxy‐1‐carbomethoxymethyl‐ethylene), obtained in presence and in absence of the complexing agent zinc chloride, was studied by means of infrared spectroscopy. A decrease of the CN absorption band and the formation of the CN band was observed, which is more clearly pronounced in the copolymers obtained in presence of ZnCl2. The obtained results are explained by the assumption of the formation of a sixmembered ring as a result of the transfer of one α‐methylene hydrogen atom from the

ISSN:0003-3146    

DOI:10.1002/apmc.1978.050700101

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractAn overview is given on the preparation and characterization of hydroxyl terminated liquid polybutadienes and polyisoprenes which are potential alternative backbones for polyurethanes. After stating the requirements for such precursors, selected routes to their production are discussed, taken from more recent literature and from own experience. Characterization encompasses new methods of end group determination, problems of functionality and fractionation. In spite of the progress achieved in various aspects, outstanding properties of e.g. carbon black‐filled polyurethanes have been reported rarely and on a larger scale commercial realization of such oligomers for high quality products seems somewhat uncertain at the momen

ISSN:0003-3146    

DOI:10.1002/apmc.1978.050700102

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractThe esters were prepared by the acryloylation or methacryloylation of 1‐formylamino‐2,2,2‐trichloroethanol and 1‐(N‐formylmethylamino)‐2,2,2‐trichloroethanol and characterized by the boiling point, melting point, and the IR spectra, The temperature of spontaneous thermal decomposition, the density, limiting oxygen number for continuous combustion and the glass transition temperature of the homopolymers of the titled compounds were al

ISSN:0003-3146    

DOI:10.1002/apmc.1978.050700103

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractThe polarographic method of analysis was applied to study cadmium ion binding in carboxymethyl cellulose (CMC) solutions. Two CMC samples of average degree of substitution 0.80 and 1.14 were selected. The degree of free ions virtually remains constant in wide range of concentrations of CMC solutions and decreases with degree of neutralization. The results are interpreted according to Oosawa's two phase model of polyelectrolytes.

ISSN:0003-3146    

DOI:10.1002/apmc.1978.050700104

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractThe structural changes which occur during the two step condensation of the liquid urea‐formaldehyde resins (UF) have been studied by NMR spectroscopy combined with chemical analyses. In the first step of the condensation (at 95°C and mildly acid reaction), the reaction takes place quickly with the formation of methylene linkages (NCH2N) and, to a minor extent, of methylol groups (NCH2OH). In the second step (at room temperature and mildly alkaline reaction) the reaction goes on very slowly, with the formation only of methylol groups. At the end the oxymethylene formaldehyde is only present as N

ISSN:0003-3146    

DOI:10.1002/apmc.1978.050700105

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractThe reaction of several dimethyl phenols with formaldehyde in alkaline medium was investigated. The addition products were separated by means of high pressure liquid chromatography and identified using IR and NMR spectroscopy. 2,3‐dimethyl phenol yields four, 2,4‐dimethyl phenol one, 2,5‐dimethyl phenol four, 2,6‐dimethyl phenol one, 3,4‐dimethyl phenol three, and 3,5‐dimethyl phenol five addition products. 3,5‐dimethyl phenol was the most reactive, 2,6‐dimethyl and 2,4‐dimethyl phenols the least reactive species. Rate constants for individual reactions were obtained from the dependence of concentrations on

ISSN:0003-3146    

DOI:10.1002/apmc.1978.050700106

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractCopolymere aus Vinylchlorid und Kohlenmonoxid oder Sauerstoff wurden als Folien unter der Einwirkung von Wärme und Licht abgebaut. Mit zunehmendem Carbonylgehalt steigt die Instabilität der Polymeren. Der thermische Abbau wird durch Luftsauerstoff beschleunigt, der photolytische dagegen verzögert. Durch die Lichteinwirkung entstehen an der Folienoberfläche Polyensequenzen; tiefere Polymerschichten werden dadurch nicht geschä

ISSN:0003-3146    

DOI:10.1002/apmc.1978.050700107

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractGrafting of styrene onto cellulose carbamate was investigated under a variety of conditions using H2O2as initiator. The graft yield was found to depend on the amount of carbamate groups, initiator and monomer concentrations as well as on temperature and pH of polymerization. The graft yield increased with increasing H2O2concentration, attained a maximum at a concentration of 0.18% then fell down sharply. Maximal grafting occurred at a monomer concentration of 6.6%. The graft yield increased also by raising the polymerization temperature up to 80°C, attained maximum at 90°C then decreased significantly. With respect to pH, the graft yield decreased markedly upon increasing the pH from 2 to 4 and marginally upon further increase in pH. Addition of FeSO4to the polymerization system caused a considerable decrement in the graft yield. A comparison between the graft yield obtained with the modified cellulose having different amounts of carbamate groups with those of the unmodified cellulose indicated that cellulose carbamates having less than 1.1% nitrogen showed lower graft yields than the unmodified cellulose. Above this, cellulose carbamate was much more amenable to grafting than the unmodified cellulos

ISSN:0003-3146    

DOI:10.1002/apmc.1978.050700108

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractThe oxidation of a macroporous glycidyl methacrylate‐ethylenedimethacrylate copolymer and of a polymer formed by its hydrolysis was investigated at temperatures ranging from 5 to 80°C with various concentrations of periodic acid. The reaction yields (formylmethyl)‐methacrylate units bearing free aldehyde groups capable of further reactions. The results allowed to estimate the activation energy of the reaction (60 and 27.5 kJ mol‐1) and to discuss its mechanism. The oxidation of the epoxide group seems to proceed in two steps with vicinal glycol as the intermediate p

ISSN:0003-3146    

DOI:10.1002/apmc.1978.050700109

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractKinetics of radical heterogeneous polymerization of N‐(2‐hydroxypropyl)methacrylamide was studied in acetone at 55°C. The values of reaction order with respect to the monomer (1.6) and to the initiator (0.5) indicate a bimolecular termination and degradative transfer during the chain growth. The over‐all rate constant of polymerization was found to be 5.6.10‐4. Addition of a small amount of a solvent (methanol) to the polymerization mixture led to an increased polymerization rate and increased molecular weight of the resulting polymer, but a higher amount of the solvent brought about a decrease of both characteristics. The Occurence of maxima on the dependences of Rp, as well as M̄won the monomer concentration was interpreted in terms of the classical Bamford and Jenki

ISSN:0003-3146    

DOI:10.1002/apmc.1978.050700110

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY