Polyethylene adhesion: Pretreatment with potassium permanganate
Abstract
Two major events occur in the modification of polyethylene (PE) surfaces by treatment with acidic KMnO4 solutions: The polymer surface is coated with a porous MnO2 layer and corroded, by oxidation. In both cases the resulting surfaces may be bonded with epoxy; the average peeling force for LDPE/epoxy/LDPE adhesive joints thus obtained may reach > 1.6 kN m−1 and is limited by adherend cohesive failure. Modified LDPE surfaces and disassembled joints were examined by transmission and ATR-IR spectrophotometry, to show that corroded, nonwettable LDPE contains appreciable amounts of polar groups, reactive towards epoxy amine components.