摘要 |
Hydrocarbon resins comprising (a) about 45 to 85% by weight of units derived from 1,3-pentadiene, (b) about 10 to 45% by weight of units derived from alpha -methylstyrene, (c) about 3 to 20% by weight of units derived from cyclopentene and (d) 0 to about 20% by weight of units derived from 1,3-butadiene and having a softening point of from about 60 DEG C. to about 140 DEG C., said hydrocarbon resins being prepared by polymerizing a monomeric mixture comprising (a) about 35 to 85% by weight of 1,3-pentadiene, (b) about 10 to 50% by weight of alpha -methylstyrene, (c) about 5 to 30% by weight of cyclopentene and (d) 0 to 15% by weight of 1,3-butadiene in a solvent comprising at least 50% by weight of an aromatic hydrocarbon in the presence of an aluminum halide as a catalyst.
|