Effect of Microstructure on Thermal, Dynamical Behavior of Metallocene Ethylene Norbornene Copolymer with Low Norbornene Content

A series of ethylene/norbornene copolymers were synthesized using the rac-Et(Ind)2ZrCl2 metallocene catalyst/ modified MAO system with low norbornene content. The copolymers were characterized by 13C NMR and DMTA to investigate the relationship between microstructure and glass transition temperature. Results revealed that both level of norbornene incorporation and microstructure have significant effect on glass transition temperature even at low norbornene incorporation. Alternating norbornene units was found to lower the rigidity, but the isolated and dyad norbornene units prevent mobility of backbone and increase Tg.