Huels Aktiengesellschaft

Huls Aktiengesellschaft

Gunter Poll

Jurgen Finke

Martin Bartmann

Harald Modler

Horst Beyer

Horst Heuer

Friedrich Sosna

Wilfred Ribbing

An aromatic polyamide molding compound, comprising:

Molding compounds based on aromatic polyamides

The invention provides aromatic polyamides having an improved resistance to thermo-oxidation. This is achieved by carrying out the polycondensation in the presence of a catalyst system which comprises a mixture of a phosphorus compound and a tin(II) compound or is a compound which contains both elements. The process according to the invention allows aromatic polyamides to be obtained which are resistant to thermo-oxidation (discoloration).

Catalytic process for the preparation of an aromatic polyamide

1. A polyamide molding compound, comprised of:

Polyamide molding compound

4,4'-bis-(4-aminophenoxy)-diphenyl sulfone (BAPS) has been prepared from 4-aminophenol and a 4,4'-dihalodiphenyl sulfone in an organic solvent in the presence of an inorganic carbonate in a one-stage reaction, a pure product having a high melting point being obtained.

Process for the preparation of 4,4'-bis-(4-aminophenoxy)-diphenyl sulfone

Molding compounds based on a thermoplastically processible aromatic polyamide. Molding compounds with an improved stability toward thermal oxidation were attained in that the molding compounds in comparison to polyamides contain chemically inert compounds of the formula I ##STR1## The molding compounds according to the invention exhibit an excellent stability toward thermal oxidation.

Molding compounds based on a thermoplastically processible aromatic

A thermoplastically processable aromatic polyamide is prepared by polycondensing diacid monomer A with diamine monomer B: (A) HOOC--Ar--COOH;(B) H.sub.2 N--Ar'--NH.sub.2 ; wherein Ar is 1,3-- or 1,4-phenylene; 1,4--, 1,5--, 2,6-- or 2,7-naphthylene, ##STR1## and Ar' is ##STR2## wherein X is --SO.sub.2 -- or --CO--; Y is --O-- or --S--; Z is --O--, --S--, --SO.sub.2 --, --CO-- or ##STR3## wherein R and R' each is --H or C.sub.1 -- to C.sub.4 -alkyl and n is 0 or 1 in the melt at a temperature in the range of from 200.degree. to 400.degree. C. in the presence of a catalyst selected from the group consisting of alkyl- or aryl-phosphonic acids, -phosphonous acids, -phosphinic acids, esters thereof, halides thereof and mixtures thereof, the catalyst content being 0.01 to 2.0 mol % relative to the total content of components A and B.

Process for the preparation of a thermoplastically processable aromatic

Aromatic polyamides with an improved stability toward thermal oxidation was achieved by polycondensation being performed in the presence of 0.05 to 4 mol % of a catalyst comprising a mixture of phosphorus compounds and metal salts. With the process according to the invention, it is possible to obtain aromatic polyamides stable toward thermal oxidation.

Melt production of a thermoplastically processible aromatic polyamide

Preparation of an aromatic polyamide with catalyst comprising

High purity 4,4'-bis(4-aminophenoxy)diphenyl sulfone is prepared from p-aminophenol, alkali metal hydroxide and 4,4'-dihalodiphenyl sulfone by using a molar ratio of alkali metal hydroxide: 4-aminophenol in the range of 1.0-1.1:1.0 and a molar ratio of 4-aminophenol: 4,4'-dihalodiphenyl sulfone in the range of 2.005-2.05:1.0 and by using a dialkylamide or N-alkyl lactam as a solvent. Pristine products (no-recrystallization) of 99.0% purity having melting points above 195.degree. C. are obtained.

Process for the preparation of 4,4'-bis(4-aminophenoxy)-diphenyl sulfone

The invention provides aromatic polyamides having a reduced melt viscosity which are derived from aromatic dicarboxylic acids, aromatic diamines and aromatic monocarboxylic acids being present in the polyamide in an amount of from 0.01 to 10 mol %. The invention allows molding compositions to be provided which have improved processability and good mechanical properties.

Growing community of inventors

Marl, Germany

Gunter Poll