Creep recovery behavior of metallocene linear low-density polyethylenes

摘要: The rheological behavior of two metallocene linear low-density polyethylenes (mLLDPE) is investigated in shear creep recovery measurements using a magnetic bearing torsional apparatus high accuracy. mLLDPE used are homogeneous with respect to the comonomer distribution. most interesting feature that their molecular mass distributions alike. Therefore, as one contains long-chain branches, influence branching on elastic properties polyethylene melts could be investigated. It was found branches increase elasticity melt characterized by steady-state recoverable compliance. branched has flow activation energy 45 kJ/mol which distinctly higher than other mLLDPE. thinning much more pronounced for A discrepancy between weight average Mw calculated from size exclusion chromatography universal calibration method and zero viscosities observed. These observations discussed reference architecture compared those classical LDPE. surprisingly very same these products although presumedly structures differ largely.