摘要:
The invention relates to new aromatic polyesters based on terephthalic acid and hydroquinones, processes for their preparation from hydroquinone and terephthalic acid derivatives, and their use for the preparation of molecularly reinforced polymers.
摘要:
Thermotropic fully aromatic polyesters which contain radicals of p-hydroxybenzoic acid, iso- and/or terephthalic acid and 2,7-dihydroxynaphthalene condensed therein, having outstanding mechanical properties and accordingly are very easy to process.
摘要:
Thermotropic aromatic polyesters which contain condensed radicals of bis-.alpha., .omega.-(4-hydroxyphenyl)-n-alkanes, have high dimensional stability under heat and at the same time high thermal stability. They can be processed thermoplastically at temperatures below 370.degree. C.
摘要:
Thermotropic fully-aromatic polyesters which contain radicals of 3,4'- and/or 4,4'-dihydroxybenzophenone in addition to radicals of p-hydroxybenzoic acid, iso- and optionally terephthalic acid, hydroquinone and/or 4,4'-dihydroxydiphenyl, have good rigidity and toughness and yet are easily processible.
摘要:
Thermotropic, fully-aromatic polyesters having a high content of 3,4'-benzophenonedicarboxylic acid radicals exhibit a combination, hitherto unknown, of good processability, high deflection temperature under load and very high strength and stiffness.
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.
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.
摘要:
Thermotropic wholly aromatic polyesters containing condensed residues of p-hydroxybenzoic acid, isophthalic and optionally terephthalic acid, hydroquinone and 3.4'- and/or 4.4'-dihydroxy diphenyl, -diphenyl ether and/or -diphenyl sulphide, have excellent mechanical properties and are nevertheless not difficult to process.
摘要:
The subject of the present invention is a process for the preparation of polyphosphonates containing carbonate structures in amounts of 0.3 to 4.5 mol %, relative to the sum of phosphonate and carbonate structural units, which is characterized in that diaryl phosphonates are reacted with diphenols in the presence of neutral transesterification catalysts, and the reaction is then completed by adding diaryl carbonate.
摘要:
Thermoplastic polyphosphonatocarbonates prepared by polycondensing at least one aromatic dihydroxy compound with a diaryl carbonate and a phosphonic acid diaryl ester in the presence of a catalyst selected from the group consisting of (a) tetra-C.sub.1 -C.sub.18 -alkyl titanates, (b) di-C.sub.2 -C.sub.4 -alkyl-tin oxides, (c) di-C.sub.2 -C.sub.4 -alkyl-di-C.sub.1 -C.sub.4 -alkoxy-tin compounds, (d) tetra-C.sub.3 -C.sub.18 -alkyl zirconates, (e) tri-C.sub.2 -C.sub.18 -alkyl vanadylates and (f) mixtures of germanium dioxide or titanium dioxide and at least one of (a) to (e) in a weight ratio of 1:3 to 3:1 at a temperature of from 80.degree.-340.degree. C. and under a pressure of 600 to 0.1 mm Hg in an inert gaseous atmosphere, the molar ratio of diaryl carbonate to phosphonic diaryl ester being from 5:95 to 95:5 and the molar ratio of aromatic dihydroxy compound to the sum of diaryl carbonates and phosphonic diaryl ester being from 0.91:1 to 0.99:1.