Polymerization of 2-allylnorbornane using Ziegler-Natta catalysts: homopolymerization

Abstract

Polymerization of 2-allylnorbornane using TiCl₄ catalyst results in a polymer which is 40% insoluble in o-xylene at 130°C, whereas with TiCl₃ catalyst, a polymer with 88% insolubility in o-xylene at 130°C is obtained. The o-xylene-insoluble fractions gave a very high melting point T_m = 355°C. The main features of these polymerizations are low catalyst activity and, in the case of TiCl₄ catalyst, competitive isomerization of the monomer. Based on a comparison with the properties of an acyclic analogue, poly(4-methyl-1-pentene), the partly insoluble nature of poly(2-allylnorbornane) and its high melting point can be attributed to the presence of the bicyclic pendant.