The potential of limited enzymatic poly(ethylene terephthalate) (PET) surface hydrolysis for the modification of track-etched (TE) membranes was investigated. Cutinases 1 and 2 from Thermobifida cellulosilytica as well as a fusion protein of cutinase 1 with the polymer binding module from the polyhydroxyalkanoate depolymerase of Alcaligenes faecalis (Thc_Cut1_PBM) were shown to hydrolyse highly crystalline PET TE membranes with a pore diameter of ∼120nm at very narrow size distribution. Furthermore the effects of surface chemistry were investigated by comparison of enzymatic hydrolysis by Thc_Cut1_PBM of "as received" PET TE membranes with two surface functionalized versions towards a "hydrophilic" and a more "hydrophobic" surface.
View Article and Find Full Text PDFThe temperature-dependent switching behavior of poly(N,N-dimethylaminoethyl methacrylate) brushes in alkaline, neutral, and acidic solutions is examined. A novel microscopic laser temperature-jump technique is employed in order to study characteristic thermodynamic and kinetic parameters. Static laser micromanipulation experiments allow one to determine the temperature-dependent variation of the swelling ratio.
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