1,140,961. Polyarylene polyether compositions. UNION CARBIDE CORP. 5 April, 1966 [8 April, 1965; 14 June, 1965; 6 July, 1965; 23 Aug., 1965], No. 15084/66. Headings C3P and C3R. A polymer composition comprises a mixture of a polyarylene polyether having recurring units of formula where E is the residuum of a dihydric phenol and E<SP>1</SP> is the residuum of a benzenoid compound having an inert electron withdrawing group in at least one of the positions ortho and para to the valence bonds, and where both of the residua are valently bonded to the ether oxygen atoms though aromatic carbon atoms, with 1 to 99% by weight of an aromatic polycarbonate polymer, or 0À1 to 20% by weight of an organopolysiloxane, or 0À1 to 20% by weight of a polyacrylate, or 0À1 to 30% by weight of a copolymer containing 30 to 70% by weight of vinylidene fluoride units and 70 to 30% by weight of hexafluoropropene units. In examples a polyarylene polyether obtained by reacting the dipotassium salt of 2,2-bis-(4-hydroxyphenyl) propane with 4,4<SP>1</SP>-dichlorodiphenylsulphone, is mixed with a polycarbonate prepared from 2,2 bis-(4-hydroxyphenyl) propane and phosgene, with various polysiloxane liquids and gums (some of these compositions include silica and iron 2-ethylhexoate), with polyethylacrylate and polybutylacrylate, and with a copolymer containing 60% by weight of vinylidene fluoride units and 40% by weight of hexafluoropropene units (some of these compositions also contain silica). The compositions of the invention may be formed into films, fibres and moulded articles, and may be used as adhesives and as electrical insulating materials, and to form matrices for printing purposes.