Evaluation of the effect of melt memory on shear : induced crystallization of low-density polyethylene

Abstract

Effect of melt memory on shear-induced crystallization of a low-density polyethylene melt is evaluated with a new shear DTA instrument. A critical strain is identified as the controlling factor for saturating the crystallization. Variation of this strain with the temperature of the sheared melt is established, and the melt state responsible for saturating the crystallization is identified by shear-stress growth experiments at the steady-state.Reptation times have been evaluated in both viscoelastic nonlinear and linear regimes, and it is shown that small-angle oscillatory shear experiments cannot be used to probe effectively the effect of shear flow on the overall crystallization kinetics.