亲水膜的表面改性及在膜蒸馏中的应用

膜的微孔性和疏水性是水溶液膜蒸馏的两个基本条件,迄今人们均采用疏水性高分子材料制成疏水微孔膜用于膜蒸馏研究。本文采用辐照接枝聚合和等离子体表面聚合的方法,将亲水的醋酸纤维素微孔膜和硝酸纤维素微孔膜表面疏水化改性,成功地用于膜蒸馏研究,大大扩展了疏水微孔膜的材料来源。实验结果表明,亲水膜表面改性得到的疏水膜,其膜蒸馏性能不低于疏水材料制成的膜,尤其是等离子体聚合法可以实现多种特殊单体在多孔的材料表面聚合,成为制备高性能疏水微孔膜的有效手段,为膜蒸馏的深入发展和实用化创造了有利条件。

Surface Modification of Hydrophilic Membranes and the Application in Membrane Distillation

The microporosity and hydrophobicity of membranes are two essential conditions for membrane distillation (M.D.) of aqueous solution. So far, the hydrophobic porous membranes have been prepared from hydrophobic materials for M.D. study. In this work, the cellulose acetate and cellulose nitrate hydrophilic membranes were modified into hydrophobic membranes by radiation grafting copolymerization and plasma polymerization, and used in M.D. study successfully. The material source of hydrophobic membrane has been expanded in full by the surface modification of hydrophilic membranes. It was indicated that the M.D. performance of modified membranes could compare with that of membranes from hydrophobic materials. Especially plasma polymerization, in which many particular kinds of monomer could be polymerized on the surface of porous materials, has become an efficient method to prepare hydrohpobic porous membrane with high performance. It will bring the M.D. into deep development and practical application.