Antifouling Membranes Prepared by a Solvent-Free Approach via Bulk Polymerization of 2-Hydroxyethyl Methacrylate

In this study, a solvent-free approach to antifouling membranes is tentatively presented. The membrane bulk matrix is formed through bulk polymerization of liquid monomer 2-hydroxyethyl methacrylate (HEMA) in the absence of an organic solvent. The membrane pores are formed via removal of silica particles generated from the sol–gel process of tetraethyl orthosilicate. The membranes have a homogeneous structure and acquire water flux around 1020 L m–2 h–1 at 0.1 MPa. The rates of rejection of the yeast and oil droplet for all the polyHEMA membranes are above 97.0 and 99.0%, respectively. The polyHEMA membranes exhibit strong hydrophilic and excellent fouling resistance properties as a result of hydrophilic HEMA. The flux recovery ratio is as high as 91.0% using protein as a foulant. After the fluorine-containing additive dodecafluoroheptyl methacrylate (DFHM) had been blended in a casting solution, the poly(HEMA/DFHM) membranes possess an amphiphilic surface and exhibit excellent fouling resistance as well as fouling release properties. The flux recovery ratio is >90%, and the total flux decline ratio is as low as 11.7% using an oil/water emulsion as the foulant.