Homogeneous Copolymers of Ethylene with α-olefins Synthesized with Metallocene Catalysts and Their Use as Standards for TREF Calibration

Summary A range of crystalline copolymers of ethylene with α-olefins (propene, hexene, octene and octadecene) were prepared using the complexes Et(Ind)2ZrCl2 and (nBuCp)2ZrCl2 activated with MAO. The average composition of the copolymers was measured using 1H- and 13C-NMR. Then the samples were characterized by High Temperature SEC and DSC. These investigations showed that polymers are homogeneous in composition and consequently were suitable to be used as standards for TREF. This work provided calibrations curves for TREF that can be used on a wide range of α-olefin contents. Finally, these calibrations curves were used to characterize heterogeneous copolymers of ethylene/hexene synthesized using a conventional Ziegler-Natta catalyst.