Process for holding and foaming thermoplastic polyphenylene sulphide articles and the resultant products

Claim 1

A process for molding a foamed article comprising (i) mixing at 150°-180° C. a polyphenylene sulphide resin and about 0.1 to 10% of a foaming agent conforming to ##STR4## wherein n is 2 to 10 and R 1 to R 4 independently denote hydrogen, chlorine, bromine, C 1 -C 10 alkyl or C 6 -H 5 , said percent being relative to the weight of said resin and said foaming agent, (ii) adding about 0.1 to 2%, relative to the weight of said polyphenylene sulphide resin, of at least one basic catalyst, (iii) heating the resulting mixture at a temperature of 280° to 350° C. for about 3 to 15 minutes to affect a reaction mixture at (iv) pouring said reaction mixture into a suitable mold for producing a foamed article, said polyphenylene sulphide being characterized in having a weight average molecular weight, measured in N-methyl-caprolactam at 150° C. on the basis of calibration with aromatic polyesters of 5000 to 60,000.