Surface modification of ultrafiltration membranes by low temperature plasma II. Graft polymerization onto polyacrylonitrile and polysulfone

摘要: Low temperature plasma-induced surface modifications of polyacrylonitrile (PAN) and polysulfone (PSf) ultrafiltration (UF) membranes were studied. Treatment with water plasma He drastically almost permanently increased the hydrophilicity PSf UF membranes. However, in contrast to behavior PAN [23], pore structure was also changed as indicated by altered permeabilities reduced protein retentions. The lower permeability (nominal Mw cut-off 10 kD) showed slower but more extended conversion due excitation stronger indications etching effects comparison 30 kD Polymer peroxides on created monitored 2,2-diphenyl 1-picryl hydrazyl (DPPH) assay. Graft polymerization hydrophilic monomers such 2-hydroxy-ethyl methacrylate (HEMA) acrylic or methacrylic acid onto membrane surfaces initiated via thermal decomposition peroxides. degree modification could be adjusted conditions. polymer modified characterized help Fourier transform infrared attenuated total reflection (FTIR-ATR) electron spectroscopy for chemical analysis (ESCA) spectra. character compared that parent With about 1–1.4 mmol/cm2 grafted HEMA, contact angles (captive bubble technique; Θoctane/water) from 48 34° 92 43°, respectively. A clear dependency amount monomer observed. type influenced permeation flux per mole acrylate specific swelling graft layer water. Hydrophilic membranes, either treatment [23] HEMA polymerization, significantly fouling static adsorption, improved performance. In particular, treated high initial retention, higher fluxes (up 150%) same even retentions obtained. Hydrophilized PSf-g-HEMA can provide performance over unmodified because are compensated yielding both filtrate (>30%) retention bovine serum albumin. Hence, induced used adjust simultaneously controlling permeability.