SYNTHESIS OF UNSATURATED POLYESTER RESIN AND APPARATUS THEREFOR

摘要

PROBLEM TO BE SOLVED: To readily enable a re-utilizing as for an unsaturated polyester resin by chemically treating a saturated polyester resin with a simple apparatus in a short time to obtain an industrially valuable raw material by decomposing the saturated polyester resin with a specific material and treating the decomposed material with a specific method. SOLUTION: A saturated polyester resin is decomposed at preferably 200-300 deg.C by using a material selected from a saturated hydroxycarboxylic acid having one carboxyl and one hydroxyl groups, lactone and lactide. An unsaturated polyester is obtained by reacting the resultant resin raw material with an unsaturated hydroxycarboxylic acid or a decomposed material of the polyester resin decomposed by the unsaturated hydroxycarboxylic acid. The polyester is crosslinked by reacting with a vinyl monomer or a diallyl phthalate. Preferably, a weight ratio of (the saturated polyester resin/the material) is (1/0.5)-(1/5).