Random hyperbranched linear polyethylene: One step production of thermoplastic elastomer

A series of random hyperbranched linear polyethylene (RHBLPE), which represents a completely new type of polyethylene, was synthesized through a single step polymerizing process of ethylene by an α-diiminonickel complex pre-catalyst. The molecular weights, branching architectures, chemical compositional distributions as well as the crystallization behavior of these RHBLPEs were carefully investigated by GPC, NMR, A-TREF and DSC, respectively. The tensile properties and elastic recoveries at different temperatures were also explored. Moreover, their distinct elastomeric properties at different temperatures were observed and charactered. It has been determined that these properties are mainly affected by the crystallization behavior of RHBLPEs. The crystallization structures of these RHBLPEs were manipulated through the polymerization temperatures of the ethylene. Thus the elastic properties of RHBLPEs could be tailored to meet different application demands at wide temperature range (-20 to 65°C).