Abstract: A resin composition including a modified acrylic unsaturated polyester resin composition comprising a maleic dicyclopentadienyl glycol polyester which is dissolved in a mixture of styrene monomer and methylmethacrylate monomer. The maleic dicyclopentadienyl glycol polyester is the reaction product of a glycol or mixture of glycols, an ethylenically unsaturated polycarboxylic acid moiety and dicyclopentadiene. The glycol utilized as a reactant preferably has a structure defined by: H--(OCHR--CH.sub.2).sub.n --OH wherein R is H or CH.sub.3 and n is 1-10. The concentration of unsaturated polyester is preferably about 40 weight percent to about 75 weight percent in the resin composition. The concentration of styrene monomer ranges from about 5 weight percent to about 40 weight percent, while the concentration of methylmethacrylate monomer ranges from about 5 weight percent to about 45 weight percent.