摘要:
Low-melting polymers containing at least one Z-configured stilbene group are produced by reaction of Z-configured bifunctional stilbene compounds with bifunctional monomers, oligomers or relatively high molecular weight components at temperatures in the range from -30.degree. to 250.degree. C., optionally in the presence of organic solvents and/or diluents and/or catalysts, the Z-configuration of the stilbene units remaining intact. The low-melting polymers may be processed by standard methods to moldings of various kinds which may be converted by treatment of temperatures of 250.degree. to 500.degree. C. and/or by irradiation at wavelengths of 200 to 800 nm into high-melting plastics articles of high heat resistance.
摘要:
The present invention relates to a process for the production of high molecular weight crystalline aromatic polyether ketones from an aromatic dihydroxy compound and an aromatic dihalogeno compound which contains a keto group, characterized in that N-C1-C5 alkyl caprolactam solvents and a mixture of alkali metal compounds consisting of at least one alkali metal carbonate and at least one compound selected from alkali metal hydroxides, bicarbonates, fluorides, hydrides, alkoxides (e.g. methylates or ethylates) and alkylates (e.g. ethyls or butyls) are used.
摘要:
Thermotropic, fully aromatic polyesters which have been prepared by polycondensation of p-hydroxybenzoic acid, hydroquinone, 4,4-dihydroxydiphenyl, terephthalic acid and isophthalic acid and which contain specific amounts of the radicals of the compounds mentioned are distinguished by an excellent toughness, very high heat distortion temperature and good processability.
摘要:
Thermotropic polyesters containing recurring structural units corresponding to the following formulae ##STR1## can be processed at low temperatures and may be used for the production of moldings, filaments, fibers and films.
摘要:
Thermotropic polyester imides having recurrent units corresponding to the following formulae: ##STR1## have excellent dimensional stability under heat and are suitable for the production of moulded articles, filaments, fibres and films.
摘要:
The thermotropic aromatic polyesters according to the invention which contain recurring units corresponding to the following formulae ##STR1## show improved resistance to chemicals, low melting points and, hence, good processibility in addition to the well-known favorable mechanical properties of liquid-crystal materials. The thermotropic aromatic polyesters are used for the production of moldings, filaments, fibers and films.
摘要:
Thermotropic, fully aromatic polyesters based on p-hydroxybenzoic acid, aromatic dicarboxylic acid and diphenol in which the dicarboxylic acid groups consist at least in part of 3,3'-diphenyldicarboxylic acid groups have excellent mechanical properties, in particular excellent elongation at break.
摘要:
The present invention relates to bis-quinoxalines of the formula I ##STR1## their preparation, their use as branching agents for the preparation of branched, thermoplastic polycarbonates and the branched thermoplastic polycarbonates.