Surface Functionalization by Grafting (2-Dimethylamino)ethyl Methacrylate Methyl Chloride Quaternary Salt (DMAEMAq) onto Hollow Fiber Polyethersulfone (PES) Membranes for Improvement of Antibiofouling Properties

Abstract

Surface modification of hollow fiber polyethersulfone (PES) membranes by UV irradiation induced graft polymerization of (2-dimethylamino)ethyl methacrylate (DMAEMAq) was developed. The grafted layers of the DMAEMAq monomer on the PES membrane surfaces were characterized using attenuated total reflectance Fourier transform infrared analysis and X-ray photoelectron spectroscopy. The performances of the modified PES membranes (PES-g-DMAEMAq) were investigated in terms of both organic fouling and biofouling. Filtration of bovine serum albumin (BSA) as a model protein and Pseudomonas putida (P. putida) as a model bacteria were carried out to evaluate organic antifouling and antibiofouling performances, respectively. The results showed that the membranes surface functionalized with the DMAEMAq monomer showed higher organic antifouling than unmodified PES membranes. A shaking flask test using P. putida also revealed that a PES-g-DMAEMAq membrane with a grafting amount of 4.8 mg/cm 2 showed higher biofouling resistance. That is, almost 99.9% of bacteria were killed by contact with the PES-g-DMAEMAq membrane. Thus, surface functionalization of PES membranes with the DMAEMAq monomer was quite useful for improving antibiofouling and organic antifouling properties.

Surface modification of polyamide TFC membranes via redox‐initiated graft polymerization of acrylic acid

“…It has been known that the surface characteristics have a highly impact on the membrane fouling resistance . The antifouling property could be improved if the membrane surface is more hydrophilic, lower roughness, or has the same charge with the foulants . In this work, the surface characterization results indicate that the TFC‐PA‐g‐AA membrane surface is more hydrophilic and smoother, thus the membrane fouling resistance should be improved.…”

“…Because of the fouling, critical pretreatment conditions and frequent membrane rinse are required, leading to significant capital and energy cost for membrane processes . In general, the membrane fouling phenomenon could be reduced when the surfaces become more hydrophilic, smoother or have the same electrical charge as the foulants . Recently, many research works have been accomplished for the development of the membrane fouling resistance, in which graft polymerization to modify membrane surface is a very useful and convenient technique.…”

Surface photochemical graft polymerization of acrylic acid onto polyamide thin film composite membranes

“…Figure shows a comparison of the decrease in flux based on the maintained flux ratio between the unmodified and the modified membranes. The surface characteristics highly impact the membrane antifouling property, which could be improved if the surfaces have a higher hydrophilicity, lower roughness, and/or the same charge as the foulants . When the filtration time increases, the fluxes of both the unmodified and modified membranes gradually decrease as a result of membrane fouling.…”

“…Different techniques can be used for the surface modification of thin film polymeric membranes such as UV‐induced graft polymerization, plasma‐induced polymerization, plasma treatment, chemical functionalization, physical coating of the polymer, and nanoparticle treatment . Using these methods, hydrophilic or charged functional groups can be introduced onto polymeric membrane surfaces, changing the surface chemistry, and topology, thus potentially reducing the fouling factors and enhancing the membrane separation performance . For enhanced membrane resistance towards fouling, UV‐photo‐induced graft polymerization is a convenient technique.…”