热处理工艺对静电纺丝制备PVDF/PMMA复合膜的力学性能的影响

Effect of Heat Treatment Process on the Mechanical Properties of PVDF/PMMA Composite Films Prepared by Electrospinning

利用热处理工艺对静电纺丝制备复合膜聚偏氟乙烯/聚甲基丙烯酸甲酯(PVDF/PMMA)进行改性,研究不同温度与不同压力对复合膜力学性能的影响,并与商用膜Celgard 2400在力学性能、离子电导率、循环性能方面进行对比。结果表明:在温度145℃,压强0.05 MPa时,PVDF/PMMA复合膜的拉伸强度为19.0 MPa,是未加压处理时其拉伸强度的10倍;PVDF/PMMA复合膜室温下的离子电导率为1.180mS/cm,比商用膜室温下的离子电导率高出187%;由PVDF/PMMA复合膜组装的纽扣电池在0.2C倍率下的放电比容量为140 (mA·h)/g,在1C倍率下的放电比容量为130(mA·h)/g,与商用膜同倍率下的放电比容量相同;在5C倍率下PVDF/PMMA复合膜的循环性能更优。

Polyvinylidene fluoride/polymethyl methacrylate(PVDF/PMMA)composite films prepared by electrospinning were mechanically modified by heat treatment process.The effects of temperature and pressure on the mechanical properties of the composite films were studied.The mechanical properties,ionic conductivities and cycling properties of the composite membranes were compared with those of commercial films Celgard 2400.The results show that the tensile strength of PVDF/PMMA composite film is 19.0MPa after a treatment at 145℃ and under a pressure of 0.05 Mpa,which is 10 times higher than that of the composite film without pressure treatment;the ionic conductivity of PVDF/PMMA composite film at room temperature is 1.180mS/cm,which is 187%higher than that of commercial film.The specific capacity of button cell assembled by PVDF/PMMA composite film is 140(mA·h)/g at 0.2C ratio and 130(mA·h)/g at 1C ratio,compared to commercial film at the same rate of discharge.The film presented better cycle performance at 5C ratio.