摘要 |
<p>1293617 Poly(arylene sulphides) PHILLIPS PETROLEUM CO 15 May 1970 [16 May 1969] 23734/70 Heading C3R In a process for obtaining aromatic polysulphides, e.g. by reacting a polyhalo-substituted aromatic compound with an alkali metal sulphide in a polar organic solvent, products of increased inherent viscosity are obtained by including in the reaction mixture preformed aromatic polysulphide polymer having a lower inherent viscosity than the final product. The preformed polymer may be a low molecular weight fraction separated from a previous batch by solvent extraction and may be added in an amount of from 3 to 50 weight per cent of the total reactants. In an example preformed poly- (phenylene sulphide) is added to a mixture of dichlorobenzene and sodium sulphide in N- methyl-2-pyrrolidone which is heated to form a polymer. Other starting materials are mentioned.</p> |