| 摘要 |
<p>1387303 Polyketones RAYCHEM CORP 15 Feb 1972 [16 Feb 1971 17 Jan 1972] 6946/72 Heading C3R Melt processable polyketones have repeating units of formula and have inherent viscosities between 0À8 and 1À65 (measured as a solution of 0À1 gm. of polymer in 100 ml. of concentrated sulphuric acid at 25‹ C.) and an elongation to break at room temperature of at least 50%. The polymers are obtained by polyermizing p-phenoxybenzoyl halides under Friedel-Crafts acetylation conditions, the reaction mixture containing an aromatic compound having a rate of reaction to acetylation relative to benzene greater than 150, which controls the inherent viscosity by endcapping the polymer chains and so terminating the polymerization. The polymer may be recovered by spray drying and may be solvent extracted. In examples polymers are obtained from p-phenoxybenzoyl chloride and from pphenoxybenzoyl fluoride in hydrogen fluoride with boron trifluoride as catalyst, the capping agents being biphenyl and diphenyl ether. Uses.-Insulation for electrical conductors, especially wires, fibres, films and moulded articles.</p> |
