Mass transport properties of co(polyether)polyurethane membranes I: Preparation and characterization

A series of polyurethane copolymers containing polyethylene glycol 600, 1000, or 1540 was synthesized, purified by reprecipitation, and cast into clear, tough, flexible membranes using the solution method. The weight average molecular weight of each polymer was estimated by gel permeation chromatography. The ability of the various polymers to absorb water was measured and increased with the increasing molecular weight of the polyethylene-glycol. The ability of the copolymer membranes to hold a pH gradient decreased with increasing polyethylene glycol molecular weight.