关键词: 聚乙烯, 取向结构, 电子显微学

Abstract: The microstructures of highly oriented melt-drawn films of high density polyethylene(HDPE), Iinear low density polyethylene (LLDPE) and low densily polyethylene (LDPE)were investigated by transmission electron microscopy(TEM).To facilitate TEM sample preparation and image interpretation the films of PE with alamellar morphology were prepared using the technique of Petermann and Gohil.Sampleswere stabilized against dimensional changes by evaporating a thin layer of carbon ontothe film surface.The melt-drawn films of PE(HDPE,LLDPE or LDPE) consist of highly oriented lamellarstructure,as a result of strain-induced crystallization during preparation of the films.Thelamellar growing direction is perpendicular to the drawing direction.Quantitative thicknessand lateral width of the lamellae were odtained from bright-field images.The averagecrystal size (lamellar thickness and width) of LLDPE or LDPE decreases as compared withthat of HDPE.The electron diffraction tilting study indicated that the film of HDPE formed anasymmetrical fibre structure or a single crystal texture and the films of LLDPE or LDPEconsisted of a syammetrical fibre structure.

Key words: polyethylene, oriented structure, electron microscopy