FIELD: chemistry.
SUBSTANCE: solid resin based on vinylacetate copolymers are obtained through copolymerisation of vinylacetate and one or more ethylene unsaturated monobasic carboxylic acids from a group comprising acrylic, methacrylic and crotonic acid. Copolymerisation is carried out in the presence of one or more mercaptoalkylcarboxylic acids with 2-6-hydrogen atoms. The obtained solid resin based on vinylacetate along with functional carboxyl links also contains terminal carboxyl groups. The solid resin based on vinylacetate copolymers as an additive reduces shrinkage of the polyester resin during solidification, removes internal stress in the resin, minimises formation of microcracks and makes easier adherence to production tolerance.
EFFECT: reduced shrinkage of unsaturated polyester resin.
6 ex, 1 tbl
