聚丙烯锂离子电池隔膜的表面接枝改性研究

Surface Graft Modification of PP Membrane for Lithium-ion Batteries

采用紫外光辐照接枝的方法,在聚丙烯(PP)锂离子电池隔膜表面接枝聚丙烯酸(PAA)。用傅立叶全反射红外光谱(ATR-FTIR)表征隔膜表面PAA的接枝情况,并考察了单体浓度、光照时间对接枝率的影响。此外,采取静态水接触角测试隔膜表面的亲水性,通过测试Gurley值来观察隔膜的透气度,用扫描电子显微镜(SEM)对隔膜表面形貌进行观测。研究了PAA接枝率对隔膜的表面亲水性、形貌、透气度的影响。结果表明,隔膜表面成功地接枝PAA;通过调节反应条件可以得到目标接枝率,改性隔膜的亲水性明显提高,同时不会明显影响隔膜多孔结构,隔膜仍具有较高的透气度。

Polyacrylic acid （PAA） was grafted to the surface of polypropylene （PP） lithium-ion battery （LIB） membrane using a surface photo-grafting process irradiated by ultra violet （UV）. The surface grafting of PAA was observed by ATR-FTIR. The influences of monomer concentration and illumination time in the grafting degree were studied. Moreover, the surface hydrophilicity was measured by static water contact angle test, the Gurley values were surveyed to character air permeability, and the membrane surface morphology was investigated through SEM. The influences of grafting degree to the surface hydrophilicity, morphology and ventilation property were studied. Results indicated that, PAA was successfully grafted onto PP membrane, and proper quality PP membrane with grafting degree could be obtained via adjusting reaction conditions, by which high- improved good hydrophilicity and high ventilation property could be prepared