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Interfacial Water and Adhesion Loss of Polymer Coatings on a Siliceous Substrate.


pdf icon Interfacial Water and Adhesion Loss of Polymer Coatings on a Siliceous Substrate. (369 K)
Nguyen, T.; Byrd, W. E.; Alsheh, D.; McDonough, W.; Seiler, J. F., Jr.

Materials Research Society Symposium Proceedings. Volume 385. 1995, 57-63 pp, 1995.

Keywords:

substrates; water; adhesion; coatings; FT-IR

Abstract:

Water is often the main cause of adhesion loss of a polymer coating/substrate system. The buildup of the interfacial water layer and the loss of adhesion of polymer-coated siliceous substrates exposed to liquid water has been investigated. The thickness of the interfacial water layer was measured on epoxy-coated SiO2-Si prisms using FTIR-multiple internal reflection (FTIR-MIR) spectroscopy. Adhesion loss on flat siliceous substrates was determined by a wet peel test on epoxy-coated SiO2-Si wafers and adhesion loss of composites was obtained by measuring the interlaminar shear strengths of epoxy/E-glass fiber composites. Both untreated and 0.1% silane-treated substrates were used. Little water was observed at the interface of the silane-treated samples but about 10 monolayers of water have accumulated at the interface of the untreated samples after 100 h of exposure to 24 DGC water. Untreated, flat substrates lost most of their bonding strengths within 75 h of exposure but silane-treated specimens retained 80% of their adhesion after 600 h of exposure to 24 DGC water. Adhesion loss of untreated composites immersed in 60 DGC water was greater than that of treated samples; however, the rate of loss of both silane-treated and untreated composites was much lower than that of flat substrates. Adhesion loss was found to follow the same trend as interfacial water buildup.