AbstractThe roller drawing of ultrahigh molecular weight polyethylene (UHMW‐PE) sheets were carried out in the roller temperatureTrrange of 100–140°C. In addition to the roller drawing in the solid state (Tr= 100°C), we attempted to crystallize the molten UHMW‐PE sheet under the roller‐drawing process (Tr= 100–140°C). The tensile and dynamic viscoelastic properties, the molecular orientation, and the microstructure of the roller‐drawn UHMW‐PE sheets were investigated. The mechanical properties of UHMW‐PE sheets were much improved by crystallization during the roller drawing process atTr= 140°C. The sheets roller‐drawn atTr= 135 and 140°C exhibitedc‐axis orientation to the draw direction and (100) alignment in the sheet plane. However, atTr= 100°C the elastic motion of the amorphous chains induces the twinnings of lattice, which enhances the transition to the (110) alignment in the sheet plane. The dynamic storage modulus below γ‐dispersion temperature showed good correlation with crystallinity and orientation functions, while taut tie molecules and thick crystallites play an important role in the storage modulus a
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