The Effect of Polymer Structure on the Gas Permeability of Model Polyurethanes

In the face of impending CFC elimination, a large variety of low-boiling alternate blowing agents have come under scrutiny for use in rigid foam insulation applica tions. The permeability of both the alternate blowing agent and atmospheric gases through the rigid foam thermoset polymer contributes to the rate at which the k-factor of the result ing foam deteriorates.