PVC-g-PVP amphiphilic polymer synthesis by ATRP and its membrane separation performance for silicone-containing wastewater

Polyorganosiloxane (silicone)-contaminated wastewater is a typical chemical wastewater that causes serious environmental pollution, is difficult to treat and has a high separation cost due to its toxicity, high chemical stability, and low surface tension. To liminate this pollution, a low-cost ultrafiltration membrane with excellent separation properties was successfully fabricated. First, to prepare the membrane, an amphiphilic polymer of poly(vinyl chloride)-g-poly(vinyl pyrrolidone) (PVC-g-PVP) was synthesized by atom transfer radical polymerization (ATRP) over an inexpensive catalyst/ligand system of CuCl/benzyl dimethylamine (BDMA). Thereafter, the membrane was fabricated by regulating the aggregation of the PVC-g-PVP amphiphilic polymer in its casting solution by increasing the solution temperature. The surface smoothness and hydrophilicity of the resulting PVC-g-PVP membrane were better than those of the pristine PVC membrane. Furthermore, the separation and anti-fouling performances of the resulting membrane for silicone-contaminated wastewater were better than those of the pristine PVC membrane. The permeation flux presented an increment of approximately 233%, with a silicone rejection rate was of approximately 100%, and the flux recovery ratio of approximately 72.7% after three cycling tests, which was an increase of approximately 423%. The integration of inexpensive BDMA was used as ligand for the synthesis of PVC-g-PVP, and hydrophilic PVC-g-PVP membrane was fabricated by regulating the aggregation of the PVC-g-PVP in solution, this work provided a new way for the fabrication of amphiphilic polymer membrane with potential application in chemical wastewater remediation.