Structure characterization of melt drawn polyethylene ultrathin films  

作　　者：YAN Chao ZHANG Jianming SHEN Deyan YAN Shouke 

机构地区：[1]State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China

出　　处：《Chinese Science Bulletin》2006年第23期2844-2850,共7页

基　　金：This work was supported by the National Natural Science Foundation of China(Grant Nos.20425414,20374056,20304018,50521302 and 20423003);the 973 Programs from M0ST of China.

摘　　要：Highly oriented ultrathin polyethylene (PE) films were prepared by a melt-draw technique. Transmission electron microscopy study on the obtained ultrathin films indicates that the melt drawn PE thin films consist of highly oriented edge-on lamellae aligned perpendicular to the drawing direction. Electron diffraction confirms that the PE chains in crystal-line phase are highly oriented in film plane along the drawing direction, while only a random orientation of the crystallographic a-and b-axes can be described through electron diffraction. The IR results on the melt-drawn ultrathin PE films demonstrate that the PE molecular chains in both crystalline and amorphous phases of the melt drawn thin films are well oriented along the drawing direction. Moreover, the IR results indicate that in the crystalline phase, the crystallographic b-axis tend to lie in the thin film plane, while in the amorphous phase, the skeleton plane of some local chains prefers to parallel the film plane. The alignment of b-axis of PE crystals in ultrathin films originates from the fact that the b-axis is the fastest growth direction of the PE crystals.Highly oriented ultrathin polyethylene （PE） films were prepared by a melt-draw technique. Transmission electron microscopy study on the obtained ultrathin films indicates that the melt drawn PE thin films consist of highly oriented edge-on lamellae aligned perpendicular to the drawing direction. Electron diffraction confirms that the PE chains in crystalline phase are highly oriented in film plane along the drawing direction, while only a random orientation of the crystallographic a- and b-axes can be described through electron diffraction. The IR results on the melt-drawn ultrathin PE films demonstrate that the PE molecular chains in both crystalline and amorphous phases of the melt drawn thin films are well oriented along the drawing direction. Moreover, the IR results indicate that in the crystalline phase, the crystallographic b-axis tend to lie in the thin film plane while in the amorphous phase, the skeleton plane of some local chains prefers to parallel the film plane. The alignment of b-axis of PE crystals in ultrathin films originates from the fact that the b-axis is the fastest growth direction of the PE crystals.

关 键 词：超薄PE薄膜 定向 红外线光谱学 电子显微术 

分 类 号：O484[理学—固体物理]