Process for the preparation of modified vinyl ether polymers

Vinyl 2-4C alkyl ether polymers are modified by reaction in presence of platinum metal compounds with compounds of formula Y-OH such that statistically at least one 2-4C alkyl group per molecule is replaced by a Y group. 2-4C alkyl vinyl ether polymers with repeat units of formula (I) are modified by reaction in presence of platinum metal compounds with compounds of formula Y-OH so as to set free the partially etherified 2-4C alcohols such that statistically at least one 2-4C alkyl group per molecule is replaced by a Y group. R = 2-4C alkyl; x = 10-1,000; and Y = (i) 5-30C aliphatic and/or cycloaliphatic hydrocarbon groups optionally with at least some of the H atoms replaced by halogen and/or aryl groups and/or (ii) aliphatic, cycloaliphatic and/or aromatic groups of mol. wt. up to 6,000 with there being at least one ether -O- or ester -COO- group in the molecule