Dynamic-mechanical properties of ethylene/α-olefin copolymers prepared by a metallocene catalyst

The influence of comonomer content and type on the dynamic-mechanical behavior of some ethylene/alpha -olefin (1-hexene, 1-octene, 1-decene, 1-octadecene and 4-methyl-1-pentene) copolymers was studied. It was observed that the comonomer content has great influence on alpha- and beta -transitions, but almost no influence on gamma -transition. Thus the alpha -transition intensity decreases and beta -transition intensity increases as the comonomer content increases. Only 1-octadecene shows a different behavior. At higher comonomer content, ethylene/1-octadecene copolymer shows two defined transitions in the alpha -transition region, suggesting the presence of crystals of different sizes.