Structure variation and puncture resistance of stretched crosslinked polyethylene film: Effects of stretching temperature

Abstract

ABSTRACTCrosslinked polyethylene films were prepared and stretched at different temperatures (below and above melting temperature). The stretching temperature exhibited pronounced effects on the structure and puncture resistance of the films. Combining the results of differential scanning calorimetry, 1D X‐ray diffraction, 2D X‐ray diffraction, and scanning electron microscope, it was demonstrated that the film stretched above T m has lower crystallinity, thinner lamellar, and larger crystal grain size than that stretched below but near T m. All the stretched films showed highly oriented lamellae in the bulk and arranged perpendicular to the stretching direction. The crystals of the film stretched below T m were arranged in highly aligned microfibrils with distinct interlamellar boundary and the crystals of the film stretched above T m were arranged in a progressively less orderly manner with increased interlamellar entanglement. Due to this structure difference, the puncture resistances of the films stretched above T m were much larger than that stretched below T m. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47542.