聚偏氟乙烯中空纤维膜的耐辐射性能研究

Study on the radiation resistance of poly-vinylidene fluoride hollow fiber membrane

研究了较低剂量的γ辐射对聚偏氟乙烯中空纤维膜的结构与性能的影响。在试验中,选用44.57 Gy/min的剂量率,分别采用2,4,6,10 kGy剂量对浸泡在pH=10的氢氧化钠溶液中的中空纤维膜进行辐照。对辐照前后的样品作相关的性能测试,结果表明:随着辐射剂量的增加,透水通量先增大后减小,最大孔径持续减小,最大幅度至14.9%,分离性能增强。在≤10 kGy的剂量内,断裂强力呈现增大趋势,断裂伸长率呈现下降趋势,爆破强度先增大后减小。工艺优化的剂量为2 kGy。微观形貌和红外分析表明,辐射对膜的外表面化学基团及内表面的形貌产生一定的影响。热分析表明,辐照使膜的结晶度有所提高。

The effect of low-level doses of gamma radiation on the properties of the poly-vinylidene fluoride （PVDF） hollow fiber membrane was studied. In the experiment, different radiation doses of 2,4, 6 and 10 kGy were chosen with the dose rate of 44.57 Gy/min. The membranes dipped in the sodium hydroxide solution with pH = 10 were irradiated and some properties tests were carried out. The results showed that the flux and porosity increased first and then decreased, the maximal pore size decreased continually to 14.9% , the tensile strength increased and the tensile elongation decreased with the increasing radiation doses. The optimized radiation dose was 2 kGy. SEM microscopy and FTIR spectroscopy show that the low-level radiation can bring about some effects on the surface and chemical structure of membranes. The results of the thermal analysis on the membranes show that the degree of crystallinity increases in some extent with the increasing radiation doses.