Study on preparation and performance characteristics of polyvinyl chloride-co-vinyl acetate-modified membranes on the nonwoven fabrics

摘要

This work reports that membranes were cast from solution consisting of dimethylformamide, polyethylene glycol, and polyvinyl chloride-co-vinyl acetate (VC-co-VAc-OH) to prepare flat-sheet membranes on the nonwoven fabrics via phase inversion method. The influence of various factors (solid content, the content of additive, environmental temperature, relative humidity, evaporation time of solvent, coagulation temperature, and coagulation time) on membrane performance (the pure water flux and the retention of bovine serum albumin (BSA)) were studied in the film-forming process of the VC-co-VAc-OH membrane. The results showed that the membrane with higher pure water flux (289.6 mL cm~(-2)h~(-1) and good retention of BSA (86.7%) can be prepared under optimized preparation conditions. In addition, the carbon dioxide gas, which was produced by a chemical reaction between glacial acetic acid in the casting solution and sodium carbonate in coagulation medium, can improve the antifouling ability of the membrane. The membrane prepared by chemical reaction under optimum conditions (the molar ratio between Na_2CO_3 and glacial acetic acid is 0.5:1) possess higher pure water flux (457.7 mL cm~(-2) h~(-1)) and good retention of BSA (90.7%).