Effect of dose and temperature on the physical properties of an aliphatic thermoplastic polyurethane irradiated with an electron beam

The electron beam irradiation of a fully aliphatic thermoplastic polyetherurethane was carried out in air at doses ranging from 50 to 4000 kGy at room temperature and 100 degrees C and a dose rate of 5.1 kGy min(-1). The effects of the irradiation on the chemical structure and the physical properties were studied. Gel was obtained already at the lower dose, increasing to almost 100% gel at the higher dose, with cross-linking predominating over chain scission. FTIR and DSC measurements proved that both, soft segment and hard segment, were affected by irradiation. Mechanical properties were adversely affected by irradiation mainly due to the cross-linking produced in the amorphous part of the material. Irradiation temperature did not have any significant effect except at the highest dose of 4000 kGy. (C) 2015 Elsevier Ltd. All rights reserved.