Structure of ultrathin polyethylene layers in multilayer films
Structure of ultrathin polyethylene layers in multilayer films
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多层薄膜中超薄聚乙烯层的结构
DOI：
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发表时间：
1990
期刊：
影响因子：
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通讯作者：
E. Baer
中科院分区：
文献类型：
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作者：
S. Pan;J. Im;M. J. Hill;A. Keller;A. Hiltner;E. Baer
在由高密度聚乙烯和聚苯乙烯交替层组成的共挤薄膜中检查了“微层”和“纳米层”聚乙烯的晶体结构。透射电子显微镜（TEM），小角X射线散射（SAXS），和广角X射线散射（WAXS）显示，微层聚乙烯，其中的层厚度是在几个微米的数量级，结晶与正常的无取向层状形态。在纳米层膜中，其中数十纳米的膜厚度在分子尺寸的尺寸尺度上，薄片以与文献中描述的结构类似的行成核形态中垂直于挤出方向的长轴取向。薄片绕长轴部分扭曲。优选的±40°扭转角使层状表面垂直于层表面取向。行成核形态赋予纳米层聚乙烯高度各向异性的机械性能。
The crystalline structures of “microlayer” and “nanolayer” polyethylene have been examined in coextruded films comprised of alternating layers of high-density polyethylene and polystyrene. Transmission electron microscopy (TEM), small-angle x-ray scattering (SAXS), and wide-angle x-ray scattering (WAXS) reveal that microlayer polyethylene, where the layer thickness is on the order of several microns, crystallizes with the normal unoriented lamellar morphology. In nanolayer films, where the film thickness of tens of nanometers is on the size scale of molecular dimensions, lamellae are oriented with the long axes perpendicular to the extrusion direction in a row-nucleated morphology similar to structures described in the literature. The lamellae are partially twisted about the long axes. The preferred twist angles of ±40° orient the lamellar surfaces normal to the layer surface. The row-nucleated morphology imparts highly anisotropic mechanical properties to the nanolayer polyethylene.