Process for the production of high molecular weight, optionally branched, polyarylene sulphides

Claim 1

A process for the production of high molecular weight, optionally branched, polyarylene sulfides which comprises condensing: (a) diahalogen benzenes; (b) aromatic tri- or tetra-halogen compound in an amount of from 0 to 2.4 mol% based on (a); (c) alkali metal sulphides, where the molar ratio of (a)+(b):(c) is from 0.85:1 to 1.15:1; in an (d) cyclic organophosphorus compound solvent, where the molar ratio of (c):(d) is from 1:2 to 1:15; over a period of up to 10 hours at a temperature of from 160° to 240° C. and where (a) are dihalogen benzenes from 50 to 100 mol%: ##STR4## wherein X represents fluorine, chlorine, bromine and iodine; and R 1 , which may be the same or different, 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 25 aralkyl and/or two of the R 1 substituents may be linked together to form an aromatic or heterocuclic ring and at least one of the R 1 substituents represents other then hydrogen; and (b) is an aromatic tri- or tetra-halogen compound: ArX.sub.n wherein Ar represents an aromatic or heterocyclic ring containing from 6 to 24 carbon atoms; and n represents 3 or 4; and (d) are cyclic organophosphorus compound solvents: ##STR5## wherein R 2 represents an unsubstituted or substituted α,ω-butylene or α,ω-pentylene; R 3 represents a C 1 -C 8 alkyl, C 6 -C 12 aryl, C 7 -C 20 aralkyl or C 5 -C 10 cycloalkyl.