AROMATIC POLYMERS

1414421 Aromatic polymers IMPERIAL CHEMICAL INDUSTRIES Ltd 2 May 1974 [25 May 1973 (2) 22 June 1973 12 Oct 1973 20 Dec 1973 14 March 1974] 25202/73 25205/73 29682/73 47684/73 59060/73 and 11443/74 Heading C3R Aromatic polymers whose molecular chains comprise 1,4-phenylene groups, oxygen atoms and ketone groups and optionally one or more 4,41-biphenylylene, terephylylene and/or sulphone groups, are obtained by heating together at temperatures of 250‹ to 400‹ C. in the presence of a sulphone having the formula in which Y is a direct link, an oxygen atom or two hydrogen atoms (one attached to each benzene ring) and Z and Z1 are hydrogen atoms or phenyl groups and may be the same or different, a monomer mixture comprising (1) 49 to 50% molar of a di(alkali metal) salt of at least one bisphenol of formula at least 95% of the phenolic OH groups being in the para position, and (2) 51 to 50% molar of at least one dihalo compound of formula where X is F, Cl or Br, and each of m and m1 is zero, 1, 2 or 3, and some of the ketone groups may be replaced by sulphone groups provided that the proportion of sulphone groups (if present) to ketone groups in the monomer mixture is not greater than 25 mole per cent and the molar percentages of monomers in the mixture sum to 100%. The polymers have reduced viscosities of between 0À8 and 3À0 (as measured at 25‹ C. on a solution of polymer in concentrated sulphuric acid (density 1À84 g./cm.3) containing 1 g. of polymer in 100 cm.3 of solution). At the reaction temperature the sulphone compound acts as a solvent. In examples this compound is diphenyl sulphone and polymers are obtained containing units of formula