拉伸工艺条件对聚氟乙烯薄膜性能的影响

Effect of Stretching Process on Properties of Polyvinyl Fluoride Film

采用挤出流延成型后经纵向拉伸和横向拉伸的方法制备了聚氟乙烯(PVF)薄膜,探讨了拉伸温度对薄膜成型的影响,优选PVF薄膜拉伸温度为纵向155~165℃和横向160~170℃,重点讨论了纵向拉伸倍率对薄膜的结晶取向、力学性能和阻隔性能的影响。结果表明,在横向拉伸倍率一定的情况下,纵向拉伸倍率增大,薄膜的结晶度和取向度提高;薄膜纵向的拉伸强度增大、热收缩率提高,而断裂伸长率明显降低;薄膜的水汽透过量降低,阻隔性提高。

In this paper,polyvinyl fluoride(PVF)film was prepared by longitudinal and transverse stretching successively after extrusion casting.The effect of stretching temperature on film processing was discussed.The stretching temperature of PVF film was preferred 155~165℃(longitudinal)and 160~170℃(transverse).The effect of longitudinal stretching ratio on the crystal orientation,mechanical properties and barrier properties of the film was discussed.The results show that as the longitudinal stretching ratio increases,the crystallinity and orientation of the film could be improved.The tensile strength and the heat shrinkage of the film increase,the elongation at break is significantly reduced.The water vapor transmission rate is reduced and the barrier property could be improved.