Process of the preparation low shrinking agent for thermosetting unsaturated polyester composite material

摘要

PURPOSE: A method for preparing a low-shrinking agent is provided, not to allow a thermosetting unsaturated polyester complex material to be shrunk in the curing process at a high temperature. CONSTITUTION: The method comprises the steps of dissolving 1-60 wt% of a fat-soluble linear polymer or copolymer in solvent to a high viscosity; adding 1-40 wt% of a monomer, an initiator and 0.01-30 wt% of a crosslinking agent to the polymer solution; and reacting the mixture at a high temperature. Preferably the fat-soluble polymer is selected from the group consisting of poly(vinyl acetate), linear polystyrene, polyethylene, polypropylene, linear poly(methyl methacrylate), polycaprolatam and their copolymers; the monomer is selected from the group consisting of styrene, vinyl acetate, acrylic acid, methacrylic acid, methyl methacrylate, ethyl methacrylate, ethylene, propylene, ethylene oxide, propylene oxide, butadiene, chloroprene, isoprene and their mixtures; the initiator is azobis(isobutylronitrile); and the crosslinking agent is selected from the group consisting of divinyl benzene, methylene bisacrylamide and ethylene glycol methacrylate.