关键词: pH值感应, 开关膜, 接枝率, 开关特性, 渗透性能

Abstract: A series of pH-responsive gating membranes, with a wide range of grafting yields, were prepared by grafting poly(acrylic acid) (PAAC) onto porous polyvinylidene fluoride (PVDF) membrane substrates with a plasma-induced pore-filling polymerization method. The effect of grafting yields on gating characteristics of pH-responsive gating membranes was investigated systematically.The results showed that the grafting yield heavily affected water flux, pH-responsiveness coefficient and pH-responsive gating factor of membrane pore size. When the grafting yield was smaller than 1.01%, both flux responsiveness coefficient and pH-responsive gating factor of pore size increased with increasing grafting yield.When the grafting yield was in the range from 1.01% to 6.44%, both flux responsiveness coefficient and pH-responsive gating factor of pore size decreased with increasing grafting yield;however, when the grafting yield was higher than 6.44%, both flux responsiveness coefficient and pH-responsive gating factor of membrane pore size approached to 1, i.e., little gating characteristics existed.In order to obtain a satisfactory pH-responsive gating property of the membrane, the grafting yield must be kept in a proper range.

Key words: pH值感应, 开关膜, 接枝率, 开关特性, 渗透性能