Preparation and permeability of a block copolymer dialysis membrane by poly(γ-methyl-L-glutamate) and poly(ethylene glycol)

The block copolymer (PMLG-b-PEG) of poly(γ-methyl-L-glutamate) (PMLG) and isocyanate-terminated poly(ethylene glycol) was synthesized. Membranes were prepared by casting 2% 1,2-dichloroethane solutions of the polymer onto a glass plate and by evaporating the solvent at room temperature. The structure and microdomain morphologies of the membranes were observed with IR spectroscopy and scanning electron microscopy, respectively. Measurement of the contact angles of deionized water on polymer membrane surfaces was made. The mechanical properties of the membranes were also determined. The permeability of the PMLG-b-PEG and PMLG membranes toward urea and creatinine was studied in a dialyzer. In all cases, the block membranes showed improved permeability toward those solutes in comparison with the PMLG membranes. The permeation coefficients of urea, through the PMLG-b-PEG300 and PMLG-b-PEG1000 membranes, were about 2.3 and 3.2 times larger than that of PMLG membranes, and for creatinine through PMLG-b-PEG300 and PMLG-b-PEG1000 membranes, were about 1.0 and 2.0 times larger than that of PMLG membranes. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68:75–82, 1998