POLYMERISATION OF CYCLOALKENES

摘要

Polyalkenamers are produced by the ring-opening polymerization of cycloalkenes. The polymerization is conducted in the presence of a homogeneous catalyst system comprising (a) a salt of a transition metal selected from the Group VIb of the periodic table; (b) an organometallic compound of a metal selected from Groups IIIa and IVa of the periodic table; and (c) an organo-silicon compound having the formula: RxSi (OR')y(OSiR3)z (Ia), (R2SiO)3 (Ib) or (R3Si)2NH (Ic), wherein R is identical or different and represents a hydrogen atom, a C1-C4 alkyl or phenyl group; R' represents a C1-C4 alkyl or phenyl group; 0/=1; x+y+z=4; and wherein the molar ratio of component (c) to component (a) is at least about 0.5:1. The catalyst system of the invention enables one to significantly increase the rate of polymerization.