Abstract: A process for making a crystallizable aromatic polymer comprises polycondensing difunctional monomers in the presence of a base and adding to the reaction mixture a nucleating agent. The nucleating agent comprises a nucleophilic group and a group of formula --A--X, where X is a metal cation and A is an anion. It is selected to give an increase in the peak crystallization temperature of the nucleated polymer compared to the unnucleated polymer.

Abstract: An aromatic polyether contains within its chain the repeat units--Ph--CO--Ph-- I--?Ph--SO.sub.2 --Ph!n-- IIat a molar ratio I/II in the range 98:2 to 80:20 where Ph represents paraphenylene; the repeat units are linked through ether oxygen; and n is at least 1.1.It can be made by reacting together hydroxy and halogeno aromatic compounds corresponding to units I and II and to any minor units that are to be present. The reactants can be provided at least partly by a polymer containing an ether-linked succession of the units.

Abstract: An aromatic polyether contains within its chain the repeat units--Ph--CO--Ph-- I--[Ph--SO.sub.2 --Ph]n-- IIat a molar ratio I/II in the range 98:2 to 80:20 where Ph represents paraphenylene; the repeat units are linked through ether oxygen; and n is at least 1.1. pa It can be made by reacting together hydroxy and halogeno aromatic compounds corresponding to units I and II and to any minor units that are to be present. The reactants can be provided at least partly by a polymer containing an ether-linked succession of the units.

Abstract: Aromatic polyetherketones and/or sulphones are produced by heating a halophenol of formula ##STR1## where X = halogen and is ortho or para to Q; Q = --CO-- or --SO.sub.2 --, Ar = an aromatic radical, with about 1/2 mole of a granular alkali metal carbonate per mole of halophenol in the presence of N-methyl pyrrolidone, dimethyl sulphone or an aromatic sulphone solvent at 200.degree.-400.degree. C.

Abstract: Process for the separation of a polyetherketone from the reaction product resulting from the nucleophilic polycondensation of (i) at least one alkali metal bisphenate with at least one dihalo compound, and/or (ii) at least one alkali metal halophenate, in an aromatic sulphone solvent of formula ##STR1## in which Y is a direct link, oxygen, or a pair of hydrogen atoms, and Z and Z' are hydrogen atoms or phenyl groups, comprising finely dividing the solidified reaction product, leaching out alkali metal halide with water and then heating the resultant finely divided material to a temperature of at least 200.degree. C but below its melting point under a vacuum to remove the water and aromatic sulphone by distillation.

Abstract: Aromatic polyether ketones, polyether sulphones and etherketone/sulphone copolymers are made by heating a molar excess of a dihalogenobenzenoid compound having halogen atoms activated by ketone or sulphone groups at 250.degree. to 400.degree. C with dialkali metal salt of a bisphenol containing ketone or sulphone linking groups in the presence of certain diaryl sulphones to form a prepolymer and then adding an additional amount of a dialkali metal salt of a bisphenol containing ketone or sulphone linking groups and continuing polymerization.

Abstract: A mixture of i) a thermoplastic copolyetherketone/sulphone containing --AR--CO (75-90%) and --Ar--SO.sub.2 -- (25-10%) repeat units wherein Ar is a bivalent aromatic radical which may vary from unit to unit and at least some of the Ar groups contain aromatic ether links ortho or para to at least one --CO-- or --SO.sub.2 -- group and ii) sulphur, a dithiol, or a polydisulphide in such a quantity that the amount of sulphur (as such or in thiol or disulphide groups) is 0.01 to 5% by weight of the combined weight of copolyetherketone/sulphone and sulphur. On heating this mixture to 300.degree.-450.degree. C the molecular weight of the polymer increases.

Abstract: Aromatic polymers of increased resistance to flow and molecular weight are obtained by irradiation using .beta.-rays or .gamma.-rays at temperatures up to 400.degree.C of an aromatic polymer whose molecular chains comprise benzenoid groups and bivalent linking groups, and where irradiation is .gamma.-rays by heating subsequent to irradiaton at 200.degree.C to 400.degree.C. The polymeric materials having increased molecular weight are useful for coating non-cooking surfaces of cookware.

Abstract: Aromatic polymers of increased resistance to flow and molecular weight are obtained by irradiation using .beta.-rays or .gamma.-rays at temperatures up to 400.degree.C of an aromatic polymer whose molecular chains comprise benzenoid groups and bivalent linking groups, and where irradiation is .gamma.-rays by heating subsequent to irradiation at 200.degree.C to 400.degree.C.