Cyclic oligomers for production of linear polyketones, polyphthalazines and polyisoquinolines

A non-film molded article of a non-melt processable linear polymer derived by ring-opening polymerization of an oligomer (I) of formula:

• ##STR48## wherein n is an integer of 2 to 20 and in which each C in the oligomer is a radical of formula (II):
• ##STR49## and each X in the oligomer is a radical of formula --O--R--O-- or --S--R--S--, in which
• A.sub.1, A.sub.2, A.sub.3 and A.sub.4 are each independently selected from hydrogen, aryl selected from the group consisting of phenyl, naphthyl and anthracyl, diphenylether or heteroaromatic radicals selected from the group consisting of pyridinyl, pyrazinyl, quinolinyl, thiophenyl, benzothiophenyl, furanyl and dibenzofuranyl, said aryl, diphenylether and heteroaromatic radicals being unsubstituted or substituted by a substituent selected from lower alkyl of 1 to 6 carbon atoms, lower alkoxy of 1 to 6 carbon atoms, lower thioalkyl of 1 to 6 carbon atoms, halogen, phenyl, naphthyl, anthracyl, diphenylether or heteroaromatic radicals selected from the group consisting of pyridinyl, pyrazinyl, quinolinyl, thiophenyl, benzothiophenyl, furanyl and dibenzofuranyl,
• B and D are both carbonyl groups CO, or
• B and D together represent a divalent radical of formula:
• ##STR50## wherein Ar.sub.3 is an aryl selected from the group consisting of phenyl, naphthyl and anthracyl, diphenylether or heteroaromatic radical selected from the group consisting of pyridinyl, pyrazinyl, quinolinyl, thiophenyl, benzothiophenyl, furanyl and dibenzofuranyl, unsubstituted or substituted by a substituent selected from lower alkyl of 1 to 6 carbon atoms, lower alkoxy of 1 to 6 carbon atoms, lower thioalkyl of 1 to 6 carbon atoms, halogen, phenyl, naphthyl, anthracyl, diphenylether or heteroaromatic radicals selected from the group consisting of pyridinyl, pyrazinyl, quinolinyl, thiophenyl, benzothio-phenyl, furanyl and dibenzofuranyl,
• Ar.sub.1 and Ar.sub.2 are each phenylene radicals, unsubstituted or substituted 1 to 4 times by a substituent selected from lower alkyl of 1 to 6 carbon atoms, lower alkoxy of 1 to 6 carbon atoms, lower thioalkyl of 1 to 6 carbon atoms, halogen, phenyl, naphthyl, anthracyl, diphenylether or heteroaromatic radicals selected from the group consisting of pyridinyl, pyrazinyl, quinolinyl, thiophenyl, benzothiophenyl, furanyl and dibenzofuranyl,
• R is arylene selected from the group consisting of phenylene, naphthylene, anthracylene, thiobisphenyl, sulfonylbisphenyl and alkylidinylbisphenyl of formula
• --Ph--R.sub.1 --Ph--
• in which R.sub.1 is a straight chain or branched alkylene of 1 to 6 carbon atoms and Ph is phenylene, in which each arylene and phenylene moiety is unsubstituted or substituted by lower alkyl of 1 to 6 carbon atoms, lower alkoxy of 1 to 6 carbon atoms, lower thioalkyl of 1 to 6 carbon atoms, halogen, phenyl, naphthyl, anthracyl, diphenylether or heteroaromatic radicals selected from the group consisting of pyridinyl, pyrazinyl, quinolinyl, thiophenyl, benzothiophenyl, furanyl and dibenzofuranyl, and the alkylidine moiety of said aralkylidinylphenylene is unsubstituted or fluoro-substituted alkylidine.