Abstract:

In order tosolve the problems of low flux and poor mechanical properties of poly(vinyl chloride) (PVC) membranes, this paper proposed a preparation method of PVC porous membrane. The PVC porous membranes were prepared with PVC as film forming polymer, polyethylene glycol, nano-silica and epoxy soybean oil as additives, γ-butyrolactone as solvent and nonwoven fabric as reinforcement by solution phase conversion method. By the morphological observation and the tesitng of pure water flux, rejection rate, pore size and their distribution, porosity and mechanical properties, the influence of the PVC solid content on the structure and properties of porous membranes were investigated. The results indicated that the cross section of the obtained PVC porous membranes have a homogeneous sponge pore structure, and the top surface is uniformly distributed with a large number of microporous structures, with the increase of PVC content in casting solutions, both of the pore size on membrane cross section and top surface, and pure water flux decreases, while the contact angle of the membrane surface increases and the hydrophilicity decreases. The maximum pure water flux of prepared PVC porous membrane can reach 1000L/(m2•h). The PVC porous membranes show good rejection performance for carbon ink, and the rejection rate reaches to 92.8%. All of the prepared PVC porous membranes’ tensile strength are higher than 20MPa, and increase with the PVC content.

Key words: poly(vinyl chloride), porous membrane, γ-butyrolactone, solution phase transformation method