采用蒸汽诱导法辅助浸没沉淀相转换法制备了硅橡胶-聚偏氟乙烯(PDMS-PVDF)疏水微孔膜并用于真空膜蒸馏NaCl水溶液,通过衰减全反射傅里叶变换红外光谱仪、X射线衍射仪、扫描电子显微镜、接触角测试仪对微孔膜的形貌结构和表面接触角进行表征和测试,研究了相对湿度对微孔膜结构和性能的影响。结果表明:随着相对湿度的增加,微孔膜表面接触角逐渐增加,孔隙率提高,平均孔径为(31±2)nm;截留率均达到99.9%以上,渗透通量先增加后降低;相对湿度为70%时制备的微孔膜渗透通量可达5.2kg/(m2·h)。
The hydrophobic microporous membrane of silicone rubber-polyvinylidene fluoride (PDMS-PVDF) was prepared by vapor-induced assisted immersion precipitation phase conversion method and used for vacuum membrane distillation of NaCl solution.The morphology and surface contact angle of microporous membranes were characterized and measured by attenuated total reflection Fourier infrared spectrometer,X-ray diffractometer,scanning electron microscope and contact angle tester,and the influence of relative humidity on the structure and properties of microporous membranes was studied.The results showed that with the increase of relative humidity,the surface contact angle and porosity of the microporous membrane increased gradually,and the average pore size was 31±2nm.The retention rate was above 99.9%,and the permeation flux increased first and then decreased.When the relative humidity was 70%,the permeation flux of the prepared microporous membrane reached 5.2kg/(m2·h).
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