Effects of Homogeneous Low Energy Electron Beam Irradiation (HLEBI) on Adhesive Energy of Peeling Resistance of Laminated Sheet with Polyurethane (PU) and Polyethylene Terephthalate (PET)

Abstract

2-layer laminated sheets (PU/PET) with Polyurethane (PU) and Polyethylene Terephthalate (PET) were prepared by a new adhesion method, a double-step treatment consisting of applying low dose (≦ 1.72 MGy) homogeneous low energy electron beam irradiation (HLEBI) prior to hot-press under 3 MPa and 348 K. Although the weak hot-press adhesion of the PU/PET was observed without HLEBI, the new adhesion mostly raised the bonding energy as evidenced by the mean adhesive energy of peeling resistance (oEp). Based on the 3-parameter Weibull equation, the lowest oEp value at peeling probability (Pp) of zero (Es) could be estimated. An increasing trend in Es occurred by the double-step treatment applying HLEBI up to 1.29 MGy reaching a maximum at 1.83 kJ·m−1, improving the safety level without radiation damage. When HLEBI cut the chemical bonds in PU and generated terminated atoms with dangling bonds, they probably induced the chemical bonding. Therefore, increasing adhesion energy between the laminated sheets could be explained.