Rheological properties of linear/branched polyethylene blend synthesized by metallocene/late metallocene hybrid catalyst

Nickel α-diimine late metallocene catalyst (LMC) capable of making branched polyethylene through chain walking mechanism and Cp2TiCl2 metallocene catalyst (MC) competent in producing linear polyethylene are simultaneously supported on MgCl2 to provide hybrid catalyst (HC). The HC is utilized in ethylene polymerization and the rheological properties of the obtained polymers are compared with rheological behavior of the samples derived by parent MC and LMC. It is shown that rheological properties change drastically upon immobilization of LMC. The HC-derived sample follows the rheological behavior of supported LMC-synthesized polymer but far from MC-catalyzed polyethylene

Keywords:

linear viscoelasticity , dynamic shear modulus , hybrid catalyst , polymerization