Effect of the morphology of reactor powders on the structure and mechanical behavior of drawn ultra-high molecular weight polyethylenes

Evolution of the straighten-chain-segment length distributions in three polyethylene reactor powders manufactured using different catalysts has been traced through the melting-drawing procedures carried out under the same temperature-deformation conditions. The powders exhibiting the presence of either folded or chain-extended crystalline entities yielded the oriented samples with quantitatively different interfibrillar structure, and, respectively, with different mechanical behavior concluded from their stress–strain curves and variation of the tangential modulus. The correlation between original and final properties of samples derived from reactor powders evidences a persistence of a kind of memory. The longitudinal disorder in nascent chain-extended crystals transforms virtually to the lateral disorder in the axially oriented interfibrillar material.