【摘 要】
：
During the fabrication of lithium battery separator,the controlling the lamellar orientation in the polymer film is very important.Here,we use the poly(ethylene oxide) (PEO) single crystal as a model
【机 构】
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College of Chemistry, Beijing Normal University, Beijing, P.R.China
【出 处】
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2012年全国高分子材料科学与工程研讨会
论文部分内容阅读
During the fabrication of lithium battery separator,the controlling the lamellar orientation in the polymer film is very important.Here,we use the poly(ethylene oxide) (PEO) single crystal as a model system to study the influence of substrates on the lamellar orientation.The recrystallization behavior of PEO on four amorphous substrates,including poly(vinyl alcohol)(PVA),lysozyme (LYSO),poly(vinylpyrrolidone) (PVPY) and poly(acrylic acid) (PAA) thin films,was investigated using atomic force microscopy (AFM) and transmission electron microscopy (TEM).The obtained results show that both the degree of supercooling and PEO/substrate interactions have had pronounced influence on the growth habit of the PEO crystals.A thermodynamic model has been proposed accordingly,in which the lamellar orientation is associated with the favorite primary nucleation.We predict the dependence of the lamellar orientation on the degree of supercooling and the surface free energy of substrate.The transition of lamellar orientation from edge-on to flat-on is determined by a critical surface free energy of the substrate which is equal to the surface tension of the polymer melt,and decreases with temperature.
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