摘要:
Improved polyamide molding compositions are characterized in that(a) the polyamide essentially contains the polycondensation product of adipic acid, terephthalic acid and hexamethylenediamine,(b) the molding compositions are reinforced with glass fibers and(c) a mixture of copper-, halogen- and phosphorus-containing compounds is present as stabilizer.
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:
Polycumylene of a relatively high degree of polymerization is obtained in a reasonable space-time yield by Friedel-Crafts alkylation of .alpha.-cumyl halide when catalyst composition, catalyst concentration and dilution ratio are selected within certain limits.
摘要:
The present invention relates to aromatic polyester(carbonate)s with end groups of the formula (Ib) ##STR1## optionally mixed with known aromatic polyester(carbonate)s, their preparation by the phase boundary process or in homogeneous solution and their modification by irradiation.
摘要:
Polyglycidyl compounds are prepared by reacting certain polyallyl compounds with a percarboxylic acid containing 3 or 4 C atoms, subsequently removing, by distillation, the carboxylic acid formed from the percarboxylic acid, then separating the remaining mixture by simultaneous extraction with a lipophilic and a hydrophilic phase, subsequently working up the laden lipophilic phase and the laden hydrophilic phase separately in a manner which is known per se, and obtaining the polyglycidyl compound as the residue from working up of the laden hydrophilic phase.
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.
摘要:
A process for the preparation of a linear or branched-chain thermoplastic aromatic polyphosphonate having an average molecular weight (number average M.sub.n) in the range of from 11,000 to 200,000, which comprises solvent-free ester interchange of at least one diaryl phosphonate or at least one diaryl phosphonate and at least one triaryl phosphate with at least one aromatic dihydroxy compound or at least one aromatic dihydroxy compound and at least one aromatic tri- or tetra-hydroxy compound or a mixture thereof in an oxygen-free gas atmosphere at atmospheric pressure or reduced pressure, with removal of the volatile constituents by distillation, and in the presence of a catalytic quantity of an ester interchange catalyst which comprises at least one compound taken from the group, C.sub.1 -C.sub.18 tetraalkyl titanates, C.sub.2 -C.sub.4 dialkyl tin oxides, C.sub.2 -C.sub.4 -di-alkyl-C.sub.1 -C.sub.4 -dialkoxy tin compounds, C.sub.3 -C.sub.18 tetraalkyl zirconates and C.sub.2 -C.sub.18 trialkyl vanadylates, antimony or bismuth salts, C.sub.2 -C.sub.4 dialkyl stannic acid esters, C.sub.2 -C.sub.4 trialkyl stannic acid esters, or a mixture of at least one compound from the above group and germanium dioxide or titanium dioxide.
摘要:
Aromatic polyesters based on diphenols, terephthalic and isophthalic acid and particular chain terminators exhibit an improved color number, an improved flowability and increased dimensional heat stability with otherwise comparable mechanical characteristics.
摘要:
Thermoplastic, branched aromatic polyphosphonates with average molecular weights (number average M.sub.n) of from 11,000 to more than 200,000, obtainable by transesterifying (a) from 97 to 100 moles of at least one diaryl phosphonate, and (b) from 0 to 3 moles of at least one triaryl phosphate--the sum of the moled of (a) and (b) being 100--with (c) from 90 to 99 moles of at least one aromatic dihydroxy compound, and (d) from 0 to 3 moles of at least one aromatic trihydroxy or tetrahydroxy compound--with the proviso that at least one of the components (b) and (d) is present in a quantity of at least 0.001 mole and that, where (b) and (d) are used, the maximum limit on the moles is 3.0.
摘要:
Melts of Urethane-modified oligoesters and 1 or polyesters can easily be dispersed in an aqueous phase in the presence of a dispersing agent combination comprising a polyether-modified polyester and a non-ionic dispersing agent having a particular HLB value.