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

摘要

A process for producing a dicyclopentadiene-modified unsaturated polyester excellent in properties required of molding materials, especially excellent long-term stability, which comprises the first step of reacting a reaction mixture of maleic anhydride (MA) and water (H2O) with dicyclopentadiene (DCPD) and the second step of reacting the resultant reaction product with a polyhydric alcohol or with a polyhydric alcohol and a polybasic acid to obtain the target polyester, wherein (1) the molar ratio of the water to the dicyclopentadiene in the first step exceeds 1 and that of the maleic anhydride to the dicyclopentadiene is 1.2 or higher, or (2) the molar ratio of the water to the maleic anhydride in the first step is 1 or lower, or (3) the requirements (1) and (2) are met in combination; a polyester resin comprising the modified unsaturated polyester and a radical-polymerizable monomer; and a molding material comprising the resin as the main component and giving a molding having excellent resistance to hot water.