Adhesion of Polyethylene/Polyethylene Terephthalate (PE/PET) Laminated Sheets by Homogeneous Low Potential Electron Beam Irradiation (HLEBI) Prior to Assembly and Hot-Press above Melting Point

Abstract

2-layer laminated sheets (PE/PET) with Polyethylene (PE) and Polyethylene Terephthalate (PET) were prepared by a new adhesion method, a double-step treatment consisting of applying low dose (≦1.30 MGy) homogeneous low energy electron beam irradiation (HLEBI) prior to hot-press under 5 MPa and 403 K. Although the weak hot-press adhesion of the PE/PET was observed without HLEBI, the new adhesion mostly raised the bonding force at interface as evidenced by the mean adhesive force of peeling resistance (^oF_p). Based on the 3-parameter Weibull equation, the lowest ^oF_p value at peeling probability (P_p) of zero (F_s) could be estimated. An increasing trend in F_s occurred by the double-step treatment applying HLEBI up to 1.08 MGy reaching a maximum at 16.0 N·m⁻¹, improving the safety level without radiation damage. When HLEBI cut the chemical bonds in PE and PET, and generated terminated atoms with dangling bonds, they probably induced the chemical bonding. Therefore, increasing adhesion energy between the laminated sheets could be explained.