RELATIONSHIP BETWEEN FILM STRUCTURE DEVELOPMENT AND EXTRUDED FILM WIDTH IN T-DIE EXTRUDING OF HIGH DENSITY POLYETHYLENE

摘要

Molecular structure development and the deformation, width and thickness behavior in T-die extruding of high density polyethylene (HDPE) was studied. The extruding through-put rate, polymer material feeding rate and winding roll temperature were fixed. The velocity of winding roll was controlled and varied independently. The effect of processing condition was analyzed from molecular orientation distribution in machine direction (MD) to transverse direction (TD) by measuring optical retardation. To analyze crystalline structure development behavior of HDPE film, wide angle x-ray diffraction (WAXD) pattern was also measured in TD of extruded film. The diffraction intensity distribution on the equator, the meridian and azimuthal direction for (110) and (200) were evaluated. We discussed major factor to control film width and thickness. Relationship between molecular structure development and the external form of extruded film was studied.