Preparation of polyurethane membrane dressing with various water vapor transmissions

Abstract

The morphology of polyurethane (PU) membranes cast from various coagulants was investigated on the basis of the precipitation values, PV, and solubility parameter, delta (h), values of various coagulants. The PV decreased with an increasing delta (h) of the coagulant. It was found that membranes cast from coagulants with a higher delta (h) h value (or lower PV) were more porous. These results were explained based on the mechanism related to the precipitation rate of the polymer, which was also supported by measuring the PU coagulation rate with various coagulants. A higher water vapor transmission, WVT, was also obtained for membranes cast from coagulants with a higher (3 h (or lower PV) due to the larger size of the voids and higher porosity of the membrane.