双向拉伸工艺对超高分子量聚乙烯隔膜性能的影响

Effect of Biaxial Stretching Process on Properties of UHMWPE Membrane

采用湿法工艺制备锂电池隔膜,并探讨了热拉伸工艺对锂电池隔膜性能的影响。结果表明拉伸温度会影响初生膜的成膜性能:在较低的拉伸温度下,同步拉伸的隔膜透气性能低于异步拉伸的隔膜,且差距较大;在较高的拉伸温度下,两种拉伸工艺制备的隔膜透气性能差距较小。拉伸倍率会影响隔膜的力学性能:在较低的拉伸倍率下,两种拉伸工艺制备的隔膜的结晶度、力学强度和热稳定性能差距不大;在较高的拉伸倍率下,同步拉伸的隔膜的结晶度和热稳定性优于异步拉伸的隔膜,但力学强度偏低。

Lithium ion battery separator was prepared by wet process,and the effect of hot stretching processes on the performance of lithium ion battery separator was discussed.The results show that the stretching temperature can affect the film-forming performance of the nascent membrane:at a lower stretching temperature,the breathability of the membrane prepared by synchronous stretching is lower than that by asynchronous stretching,and the gap is larger;at higher stretching temperature,the difference of breathability between the two stretching processes is smaller.Stretching ratio can affect the mechanical properties of the membrane:at a lower stretching ratio,the crystallinity,mechanical strength and thermal stability of the membrane prepared by the two stretching processes have little difference;at a higher stretching ratio,the crystallinity and thermal stability of the membrane prepared by synchronous stretching are better than those by asynchronous stretching,but the mechanical strength is lower.