Structural Evolution of Ultra-High Molecular Weight Polyethylene Low-Entangled Films with Reserved Shish Crystals During Hot Stretching  

作　　者：Jia-Wei Gao Li Chen Ye-Shun Zhong Chao-Wei Xing Yi-Guo Li Zong-Bao Wang 

机构地区：[1]School of Materials Science and Chemical Engineering,Ningbo University,Ningbo 315211,China

出　　处：《Chinese Journal of Polymer Science》2024年第8期1227-1242,共16页高分子科学（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(Nos.52173021 and 52373038);Key Research and Development Programme of Zhejiang Province(No.2023C01209);S&T Innovation 2025 Major Special Programme of Ningbo(No.2023Z079)。

摘　　要：Shish crystals are crucial to achieving high performance low-dimensional ultra-high molecular weight polyethylene(UHMWPE)products.Typically,high stretch and shear flow fields are necessary for the formation of shish crystals.In this study,UHMWPE gel films with reserved shish crystals were prepared by gel molding,the structural evolution and properties of UHMWPE films stretched at temperatu res of 100,110,120and 130℃were investigated by in situ small-angle X-ray scattering(SAXS)/ultra-small-angle X-ray scattering(USAXS)/wide-angle X-ray diffraction(WAXD)measu rements as well as scanning electron microscopy(SEM)and differential scanning calorimetry(DSC)measurements.Our findings showed that the reserved shish crystals can facilitate the formation and structural evolution of shish-kebab crystals during the hot stretching.Additionally,the reserved shish crystals promote the structu ral evolution of UHMWPE films to a greater extent when stretched at 120 and 130℃,compared to 100 and 110℃,resulting in higher crystallinity,orientation,thermal properties,breaking strength and Young's modulus.Com pared to UHMWPE high-entangled films with reserved shish crystals prepared by compression molding,UHMWPE low-entangled films with reserved shish crystals prepared by gel molding are more effective in inducing the formation and evolution of shish-kebab crystals during the hot stretching,resulting in increased breaking strength and Young's modulus.

关 键 词：UHMWPE low-entangled films Reserved shish crystals Structural evolution Hot stretching 

分 类 号：TQ325.12[化学工程—合成树脂塑料工业] TB383.2[一般工业技术—材料科学与工程]