Polyurethane urea membranes for membrane blood oxygenators: synthesis and gas permeation properties

Abstract

A custom-made set-up was constructed and opti-mized for the measurement of the gas permeation properties of membranes at constant temperature. Integral asymmetric membranes and dense symmetric membranes of poly(ester urethane urea) were synthetized and characterized in terms of: i) structure by Scanning Electron Microscopy (SEM), and ii) gas permeation properties for N2, CO2 and O2 in the custom-made set-up. The membranes were synthesized by a modified version of the phase inversion technique where polyurethane and polycaprolactone-diol prepolymers react in a solvent mixture of dimethyl formamide and diethyl ether. The total polymer to solvent weight ratio, the solvent evaporation time and the polycaprolactone quantity were varied.