DICYCLOPENTADIENE-MODIFIED UNSATURATED POLYESTER, PROCESS FOR PRODUCING THE SAME, AND RESIN AND MOLDING MATERIAL EACH CONTAINING UNSATURATED POLYESTER

摘要

The present invention discloses a process for producing a dicyclopentadiene-modified unsaturated polyester, which is superior in characteristics for molding material, especially stability. The process includes a first step of reacting a reaction mixture of maleic anhydride (MA) and water (H₂O) with dicyclopentadiene (DCPD) and a second step of reacting the reaction product obtained in the first step with a polyhydric alcohol, or a polyhydric alcohol and a polybasic acid, to obtain an unsaturated polyester modified with dicyclopentadiene. In the first step of the process,(1) a molar ratio of water to dicyclopentadiene is greater than 1 and a molar ratio of maleic anhydride to dicyclopentadiene is 1.2 or more,(2) a molar ratio of water to maleic anhydride is 1 or less, or(3) both of the features (1) and (2) are satisfied. The present invention also discloses a polyester resin composition containing the modified unsaturated polyester and a radically polymerizable monomer, and a molding material containing the resin composition as a main component. The molding material gives a molded article having excellent hot water resistance.