Structural features of 4-methyl-1-pentene polymers prepared with different transition metal catalysts

Homopolymerization of 4-methyl-1-pentene carried out in the presence of catalysts containing variable relative amounts of Ti, Hf and Mg indicates that molecular weight and stereoregularity can be varied to an appreciable extent depending on catalyst nature and composition. A distinct behaviour of the various catalytic systems is also observed during the copolymerization of 4-methyl-1-pentene with monoalkenes such as propylene, 1-butene and 1-hexene. These data are discussed by underlining the important role of the transition metal in determining the features of polyolefins materials.