title: Surface self-assembled PEGylation of fluoro-based PVDF membranes via hydrophobic-driven copolymer anchoring for ultra-stable biofouling resistance.
abstract: Stable biofouling resistance is significant for general filtration requirements, especially for the improvement of membrane lifetime. A systematic group of hyper-brush PEGylated diblock copolymers containing poly(ethylene glycol) methacrylate (PEGMA) and polystyrene (PS) was synthesized using an atom transfer radical polymerization (ATRP) method and varying PEGMA lengths. This study demonstrates the antibiofouling membrane surfaces by self-assembled anchoring PEGylated diblock copolymers of PS-b-PEGMA on the microporous poly(vinylidene fluoride) (PVDF) membrane. Two types of copolymers are used to modify the PVDF surface, one with different PS/PEGMA molar ratios in a range from 0.3 to 2.7 but the same PS molecular weights (MWs, ∼5.7 kDa), the other with different copolymer MWs (∼11.4, 19.9, and 34.1 kDa) but the similar PS/PEGMA ratio (∼1.7 ± 0.2). It was found that the adsorption capacities of diblock copolymers on PVDF membranes decreased as molar mass ratios of PS/PEGMA ratio reduced or molecular weights of PS-b-PEGMA increased because of steric hindrance. The increase in styrene content in copolymer enhanced the stability of polymer anchoring on the membrane, and the increase in PEGMA content enhanced the protein resistance of membranes. The optimum PS/PEGMA ratio was found to be in the range between 1.5 and 2.0 with copolymer MWs above 20.0 kDa for the ultrastable resistance of protein adsorption on the PEGylated PVDF membranes. The PVDF membrane coated with such a diblock copolymer owned excellent biofouling resistance to proteins of BSA and lysozyme as well as bacterium of Escherichia coli and Staphylococcus epidermidis and high stable microfiltration operated with domestic wastewater solution in a membrane bioreactor.
authors.affiliation: R&D Center for Membrane Technology and Department of Chemical Engineering, Chung Yuan Christian University, Jhong-Li, Taoyuan 320, Taiwan.
authors.forename: Nien-Jung
authors.initials: NJ
authors.lastname: Lin
authors.forename: Hui-Shan
authors.initials: HS
authors.lastname: Yang
authors.forename: Yung
authors.initials: Y
authors.lastname: Chang
authors.forename: Kuo-Lun
authors.initials: KL
authors.lastname: Tung
authors.forename: Wei-Hao
authors.initials: WH
authors.lastname: Chen
authors.forename: Hui-Wen
authors.initials: HW
authors.lastname: Cheng
authors.forename: Sheng-Wen
authors.initials: SW
authors.lastname: Hsiao
authors.forename: Pierre
authors.initials: P
authors.lastname: Aimar
authors.forename: Kazuo
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Juin-Yih
authors.initials: JY
authors.lastname: Lai
mesh_terms: D000818:Animals; D057219:Biofouling / Q000517:prevention & control*; D002417:Cattle; D004926:Escherichia coli / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D015394:Molecular Structure; D009113:Muramidase / Q000737:chemistry / Q000378:metabolism; D011092:Polyethylene Glycols / Q000737:chemistry*; D011145:Polyvinyls / Q000138:chemical synthesis* / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000737:chemistry; D013212:Staphylococcus epidermidis / Q000737:chemistry; D013499:Surface Properties; D005465:Fluorocarbon Polymers
chemical_list: D009113:Muramidase; D011092:Polyethylene Glycols; D011145:Polyvinyls; D012710:Serum Albumin, Bovine; C024865:polyvinylidene fluoride; D005465:Fluorocarbon Polymers