接枝丙烯酸对聚偏氟乙烯膜表面亲水改性的研究

Studies on Surface Modification of PVDF Membranes by UV Grafted Acrylic Acid

摘要: 为了改善传统聚偏氟乙烯(PVDF)亲水性不强的缺点，本研究以二苯甲酮(BP)为光引发剂，通过紫外光照，将亲水性单体丙烯酸接枝于PVDF膜的表面。通过测试纯水接触角和吸水率的表征值，考察PVDF膜改性前后的亲水性的变化，并且确定了引发剂浓度、辐照时间等因素对接枝率的影响。结果发现接枝后的PVDF膜的亲水性得到明显改善，而且随着光引发剂浓度的增大，丙烯酸的接枝率先增大而后在一定区间内保持稳定。本实验还通过衰减全反射光谱和扫描电子显微镜图片对接枝后PVDF膜表面化学组成和微观形貌进行了表征。

Abstract: To improve the hydrophilic property for the traditional PVDF, acrylic acid was grafted onto the surface of PVDF membrane by UV irradiation grafting polymerization with benzophenone as photo-initiator. The static contact angle and water absorption ratio were used to study the changes of hydrophilic property of modified PVDF membranes, and the principal factors influenced the grating degree were discussed, such as the concentration of photo-initiator, irra-diation time. The results showed that the hydrophilic property of PVDF membranes was improved significantly, and with the increase of the concentration of photo-initiator, the degree of grafting increased first, then stayed stable in a certain range. We also used attenuated total reflection-Fourier transform infrared spectroscopy and scanning electron mi-croscopy to characterize the chemical structure and morphological changes of the original and modified PVDF membrane.