This invention relates to a reaction product obtained by contacting a polymer comprising units derived from dicyclopentadiene with a vinyl terminated macromonomer, a vinyl monomer or a vinylene monomer, in the presence of a metathesis catalyst, where the vinyl monomer or vinylene monomer is represented by the formula: wherein each X is, independently, —CO2R, —CONR1R2, CN, a C1 to a C20 alkyl group; R is a C1 to a C20 alkyl group or an aromatic group; each R1 and R2 is, independently, a hydrogen, a C1 to a C20 alkyl group, or an aromatic group; each R5 is, independently, a hydrogen atom or a C1 to a C40 alkyl group; each Ar is, independently, an aromatic group; and each n is, independently, from 0 to about 40.