Adhesion Reinforcement by Homogeneous Electron Beam Irradiation at Room Temperature of Laminated Sheet with Polymethyl Methacrylate (PMMA) and Polydimethysiloxane (PDMS)

The effects of homogeneous electron beam irradiation (EBI) at room temperature on the adhesive force of peeling at each peeling probability (Pp) of laminated sheets of bio-adaptable polydimethylsiloxane (PDMS) with great formability property and chemical resistance polymethyl methacrylate (PMMA) with sterilization were investigated without glue. EBI within the range of 0.22 to 0.30 MGy increased the adhesive force of peeling (°Fp) at higher cumulative probabilities from 0.77 to 0.94, substantially over the untreated. The largest °Fp values at optimal dose of 0.22 MGy were 116.0 Nm-1, which were more than 17 times larger than 6.7 Nm-1 of the untreated at high peeling force at the highest cumulative probability of 0.94. XPS (X-Ray Photoelectron Spectroscopy) observations of the peeled 0.22 MGy irradiated PMMA revealed generation of a SiC peak at 101.3 eV possibly explaining the increased adhesion. The residual PDMS deposition is apparently found to be retained on the PMMA by inter-matrix fracture of PDMS further into the thickness. This can be explained by the adhesion force between PMMA/PDMS being stronger than the cohesive force of PDMS polymer itself.