abstract |
A hydrocarbon polymer modifier (HPM) having high softening point and high aromaticity, is an interpolymer of (i) a piperylene component; (ii) an aromatic component; and (iii) a cyclic pentadiene component comprising a dicyclopentadiene fraction (DCPD fraction) and a dimethylcyclopentadiene fraction (MCPD fraction), wherein a weight ratio of the MCPD fraction to the DCPD fraction is from 0.8 to 20, and wherein the MCPD fraction is at least 20 wt % of the cyclic pentadiene component. In a method, the proportions of (i), (ii), (iii), and an optional amylene component are adjusted to control aromaticity, softening point and Mz of the HPM. An elastomeric composition incorporates the HPM. |