(601f) A Solvent-Free Approach to Prepare Antifouling, High-Flux polyHEMA Membrane

Currently, most of synthetic polymer membranes are prepared from solution in organic solvents using approaches such as phase inversion and solvent evaporation. However, extensive utilization of organic solvents in membrane processing has deleterious effects because it contributes significantly to the cost of membrane manufacture and ultimately requires heavy disposal of the solvents. Herein, a solvent-free approach to prepare polymer membrane is proposed. The membrane is prepared through bulk polymerization in a confined gap between two glass slides. Initiated by thermal decomposition of benzoyl peroxide, the liquid monomer 2-hydroxyethyl methacrylate (HEMA) polymerizes and solidifies into solid membrane. 1, 6-hexanedioldiacrylate (HDODA) with two vinyl bonds is utilized to increase molecular weight of polyHEMA and enhance mechanical strength of membrane. The tetraethyl orthosilicate (TEOS) is first converted into silica particles and the resultant inorganic template is then removed by hydrofluoric acid to acquire porous membrane. The porous polyHEMA membranes show strong surface hydrophilicity and ultra-low protein adsorption. Microfiltration was carried out to assess the permeability and fouling resistance properties of the membranes. The water permeability is remarkably enhanced from 316 L/(m2h) to 8549 L/(m2h) with the ratio of TEOS to HEMA increasing from 1:4 to 3:1. When the aqueous mixture of yeast and bovine serum albumin (BSA) filtrated, most yeast (above 95%) is retained and almost all the BSA penetrates through. The flux recovery ratio (FRR) can reach 95.1%, showing excellent antifouling property. Multi-run experiments demonstrate that the antifouling property maintains after long-term operation.