| 主权项 |
1. A process for the preparation of at least one hydrocarbon polymer, said process comprising at least one stage of ring opening metathesis polymerization in the presence:
of at least one metathesis catalyst, preferably a ruthenium-comprising catalyst, more preferably still a Grubbs' catalyst, of 4-ethenyl-1,3-dioxolan-2-one (or vinyl ethylene carbonate) as chain transfer agent (CTA), and at least one compound chosen from compounds comprising at least one hydrocarbon ring and generally from 6 to 16, preferably from 6 to 12, carbon atoms per ring, said ring comprising at least one carbon-carbon double bond, and the substituted derivatives of this compound, said compound generally being of formula (7): each carbon-carbon bond of the chain denoted is a double bond or a single bond, in accord with the valency rules of organic chemistry; the R1 and R6 groups are either both hydrogen or each different from hydrogen and bonded to one another as members of one and the same ring or heterocycle which is saturated or unsaturated; the R2, R3, R4 and R5 groups are each, independently or not of the other groups, a hydrogen, a halo group, an alkoxycarbonyl group or an alkyl group, it being possible for the R2 to R5 groups to be bonded to one another as members of one and the same saturated or unsaturated ring or heterocycle; m and p are integers each within a range extending from 0 to 5, the sum m+p being itself within a range from 0 to 6; said stage being carried out for a period of time of less than or equal to 2 h, preferably from 1 hour to 2 hours. |
