Synthesis of Comb-Branched Polyolefinic Elastomers Using a Tandem System with FI-Ti and CGC-Ti Catalysts

Using two combined catalysts in one reactor is an efficient way for synthesizing polyolefin copolymers with unique structures. Olefin block copolymers (OBCs) are one of examples which are produced by two distinct catalysts with different copolymerization ability in a single reactor. In our tandem system, a bis(phenoxyimine)-titanium (PTFI-Ti) was used as a macromonomer catalyst for the synthesis of linear polyethylene (PE) macromonomers with terminal vinyl groups, while a CGC-Ti catalyst (CGC-Ti) was served for copolymerization of ethylene, 1-octene, and PE macromonomer at a wide range of operation temperatures to form comb-branched polyolefin copolymers with long chain (LCB). The resulting comb-LCB copolymers with crystalline polyethylene as side chains and amorphous ethylene/1-octene random copolymers as backbone possessed good thermoplastic elastomer properties.