摘要:
Thermotropic fully aromatic polyester carbonates containing condensed residues of optionally substituted 3-hydroxybenzoic acid have great rigidity, impact strength and elongation at break and yet can be processed under the usual conditions owing to their advantageous fusion viscosity.
摘要:
Thermotropic, fully aromatic polyesters and polyester carbonates are produced by esterification of optionally substituted p-hydroxybenzoic acids and aromatic dicarboxylic acids with diaryl carbonate at temperatures in the range from 100.degree. to 220.degree. C. and subsequent transesterification of the aryl ester obtained with diphenols and, optinally, more diaryl carbonate, accompanied by polycondensation, at temperatures in the range from 250.degree. to 330.degree. C., the esterification, the transesterification and the polycondensation being carried out in the presence of heterocyclic compounds containing 1 to 3 nitrogen atoms.
摘要:
This invention relates to a process for the preparation of optionally branched polyarylene sulphides which are distinguished by their substantially lower corrosiveness.
摘要:
This invention relates to a process for the preparation of high molecular weight, optionally branched polyarylene sulphides. These may be prepared in polar organic solvents in the absence of water, substances containing water being dehydrated in the reaction mixture before the reaction.
摘要:
The invention relates to a process for the production of optionally branched polyarylene sulfides by reacting dihalogen benzenes in admixture with aromatic polyhalogen compounds and alkali sulfides in polar solvents, the reaction being carried out in the presence of reducing agents.
摘要:
This invention relates to a process for the production of high molecular weight, optionally branched polyarylene sulphides. These polyarylene sulphides may be produced in a polar organic solvent in the absence of water in a one-vessel reaction.
摘要:
The invention relates to thermally stable, weather-resistant polyamide moulding compositions containing as stabiliser, a mixture of a copper halide, one or more halogen compounds and hypophosphorous acid or an alkali metal or alkaline earth metal salt of this acid, wherein the individual components of the stabiliser mixture are added in an amount such that the molar amount of halogen contained in the moulding composition is greater than or equal to six times the molar amount of and less than or equal to fifteen times the molar amount of copper contained in the moulding composition and the molar amount of phosphorus is greater than or equal to the molar amount of and less than or equal to ten times the molar amount of copper contained in the moulding composition.
摘要:
This invention relates to a process for the preparation of high molecular weight, optionally branched polyarylene sulphides. These may be prepared from alkali metal sulphides and aromatic halogen compounds in a polar organic solvent in the absence of water.
摘要:
This invention relates to optionally branched polyarylene sulphides and a process for the production thereof in a polar solvent, from 0.2 to 100 mole %, based on the aromatic dihalogen compounds, of an amino acid being added to the reaction mixture.
摘要:
This invention relates to a process for the production of high molecular weight, optionally branched polyarylene sulphides from alkali metal sulphides and halogenated aromatic compounds in the presence of from 0.5 to 100 mol %, based on the molar quantity of aromatic dihalogen compounds, of an ester or anhydride of a carboxylic acid.