私密直播全婐app免费大渔直播,国产av成人无码免费视频,男女同房做爰全过程高潮,国产精品自产拍在线观看

當(dāng)前位置:> 首頁 > 論文著作 > 正文
Lamella reorientation in thin films of a symmetric poly(L-lactic acid)-blockpolystyrene upon crystallization at different temperatures
作者:Fu, J.; et al.
關(guān)鍵字:Crystalline-Coil, Crystallization, Thin film, lamellae
論文來源:期刊
具體來源:Polymer, 2009, 50, 1588-1595.
發(fā)表時間:2009年

The thin films of a symmetric crystalline-coil diblock copolymer of poly(L-lactic acid) and polystyrene (PLLA-b-PS) formed lamellae parallel to the substrate surface in melt. When annealed at temperatures well above the glass transition temperature of PLLA block (Tg PLLA), the PLLA chains started to crystallize, leading to reorientation of lamellae. Such reorientation behavior exhibited dependence on the correlation between the crystallization temperature (Tc), the glass transition temperature of PS (TgPS), the peak melting point of PLLA crystals (TmPLLA), and the end melting point of PLLA crystals (Tm,end PLLA). When annealed at (Tc =) 80C (Tc< TgPS< TODT, order–disorder transition temperature), 123C (TgPS< Tc< TmPLLA<TODT), 165C (Tg PS< TmPLLA<Tc < Tm,endPLLA <TODT), the parallel lamellae became perpendicular to the substrate surface, exclusively starting at the edge of surface relief patterns. Meanwhile, the corresponding lamellar spacing was significantly enhanced. The PLLA crystallization between PS layers was hypothesized to account for the lamella reorientation during annealing. The crystallization, chain conformation, and possible chain folding mechanisms were discussed, based on detailed analysis of the lamellar structure before and after crystallization.

主站蜘蛛池模板: 建始县| 怀远县| 庆阳市| 综艺| 连城县| 昔阳县| 永新县| 牟定县| 怀集县| 酒泉市| 班戈县| 台州市| 大余县| 巴马| 江城| 叶城县| 青海省| 德钦县| 东明县| 松原市| 嘉黎县| 弋阳县| 海兴县| 靖西县| 本溪市| 华蓥市| 沈阳市| 高要市| 甘德县| 陈巴尔虎旗| 长岛县| 息烽县| 尉犁县| 阿克苏市| 邯郸市| 鄱阳县| 桃江县| 新安县| 手游| 南通市| 枣强县|