Blending of copolymers

摘要

A process for the preparation of an ionic copolymer comprises admixing, at an elevated temperature, a copolymer of one or more a -olefine of the formula RCH = CH2 where R is hydrogen or an alkyl group containing 1 to 8 hydrogen or an alkyl group containing 1 to 8 carbon atoms and one or more a ,b -ethylenically unsaturated carboxylic acids (defined), the olefine comonomer content being from 0.2 to 25 mol per cent in the copolymer, with (a) an ionic metal compound soluble to the extent of at least 2 weight per cent in water, the metal ion in the metal compound having a valence of 1, 2 or 3 when the acid comonomers are monocarboxylic and a valence of 1 when the acid comonomers are dicarboxylic; or (b) a compound containing a cation of the formula where R and R1 is H or an alkyl radical containing 1 to 5 carbon atoms, R11 and R111 are H or alkyl radicals containing 1 to 5 carbon atoms or together form an alkylene radical containing 2 to 10 carbon atoms, m is an integer from 0 to 4, n is an integer from 0 to 10 and X is a carbon to carbon bond, a divalent alkylene radical containing up to 30 carbon atoms, an oxygen or sulphur atom, or an imine, carbonyl or phenylene radical, said compound having a dissociation constant above 10-8; or (c) a metal compound which is soluble to the extent of at least 2% by weight in water, which consists of a complex metal cation ionically linked to an anion radical, which radical when combined with hydrogen forms a product which is volatile at the temperature of mixing, the complex metal cation having a residual positive electrovalence of 1, 2 or 3 when the acid comonomers are monocarboxylic acids and of 1 when the acid comonomers are dicarboxylic acids; the quantity of said metal compounds or amino compounds used being such that at least 10 and preferably 50% of the carboxylic acid groups are neutralized by the cations formed from said compound; the admixing being carried out by (a) forming particles of the copolymer into a slurry with a liquid containing said compound, reacting said compound with the copolymer and then recovering the copolymer particles or (b) injecting the compound containing the cations to be reacted with the carboxyl acid groups into the polymerization reactor in which the copolymer has been formed while the copolymer is still molten or in solution or (c) blending the compound with the copolymer in an extractor-extruder.