SOLUBLE CROSS-LINKABLE COPOLYMERS BASED ON VINYL ESTER, VINYL AROMAT AND ACRYLATE MONOMERS, PROCESS FOR THEIR PRODUCTION AND THEIR USE IN COATINGS

摘要

The invention relates to copolymers containing onaverage 1.25 to 30 functional groups per molecule and anumber average molecular weight of 1500 to 6000, whichcopolymers can be prepared by free-radical solutionpolymerization at 130 to 200°C from 5 to 25% by weight ofvinyl ester, 10 to 50% by weight of vinyl aromatic, 10 to40% by weight of functional, monomers and, if desiredfurther monomers, in which the vinyl ester is initiallyintroduced and the remaining monomers are metered in forall monomers over a monomers addition period which is ofthe same length in the following manner:The amount of acrylate monomers added per unit oftime remains constant.The amount of vinyl aromatic added over the firstthird of the monomer addition period is 15 to 30% byweight, the amount added over the second third is 25 to40% by weight, and the amount added over the last thirdis 35 to 60% by weight, each relative to the total amountof vinyl aromatic.The copolymer obtained is, if desired, reactedwith compounds containing a group which is reactivetowards the functional groups of the copolymer and atleast one crosslinkable group.