Process for the production of polyarylene (sulphides) having an increased thermal and chemical resistance and an improved color quality

Claim 1

A process for the production of a high molecular weight, branched polyarylene sulphide which comprises reacting (a) at least one dihalogen benzene, from 50 to 100 mol % of which corresponds to the formula ##STR4## and from 0 to 50 mol % of which corresponds to the formula ##STR5## wherein X represents fluorine, chlorine, bromine or iodine, and each R 1 is the same or different and represents hydrogen, C 1 -C 20 alkyl, C 5 -C 20 cycloalkyl, C 6 -C 24 aryl, C 7 -C 24 alkaryl or C 7 -C 24 aralkyl or two adjacent radicals are joined to complete an aromatic or heterocyclic ring and the other two R 1 radicals are either joined to complete an aromatic or heterocyclic ring or are each hydrogen, or the aforesaid alkyl, cycloalkyl, aryl, alkaryl or aralkyl radicals, at least one radical R 1 being other than hydrogen, (b) from 0.2 to 2.4 mol % based on (a) of a compound of the formula ArX n wherein Ar represents an aromatic or heterocyclic radical having from 6 to 24 carbon atoms, X is as aforesaid and n is 3 or 4 and (c) at least one alkali metal sulphide, or a mixture thereof with an alkali metal hydroxide, the mol ratio of (a+b):c being from 0.85:1 to 1.15:1, in (d) at least one cyclic urea which is completely alkylated on each nitrogen atom, the mol ratio of (c) to (d) ranging from 1:2 to 1:15, at a temperature of from 250° to 290° C. and a pressure of from 4 to 20 bars.