Effects of Crosslink Density on Surface and Interface Properties of Amine-Cured Epoxy
Xiaohong Gu, Tinh Nguyen, Mark R. VanLandingham, D T. Raghavan
The effect of network changes on the surface and interface properties of amine-cured epoxy has been investigated. Samples of different crosslinked epoxies are prepared by mixing stoichiometrically pure diglycidyl ether of bisphenol A (n=0.03) with different ratios of 1,3-bis(aminomethyl)cyclohexane (terafunctional amine) and cyclohexylmethylamine (difunctional amine). Both free films and films applied to a silicon substrate are used for the analysis. All samples are cured in CO2-free air. The crosslink density is measured by dynamic mechanical analysis (DMA). Both the film surface in contact with air and that in contact with the silicon substrate (the interface) of different crosslinked epoxies are analyzed using atomic force microscopy (AFM), nano-indentation, X-ray phoelectron spectroscopy (XPS), attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, and contact angle measurements. Results show a strong influence of crosslink density on the surface and interface properties of amine-cured epoxy. Substantial chemical and morphological differences between the surface and the interface are also observed for different network epoxies. The effect of crosslink density on surface and interface properties have strong implications on the wettablity, adhesion, and durability of amine-cured epoxies.
The 25th Annual Meeting of The Adhesion Society, Inc. and The Second World Congress on Adhesion and Related Phenomena (WCARP-II)
, Nguyen, T.
, VanLandingham, M.
and Raghavan, D.
Effects of Crosslink Density on Surface and Interface Properties of Amine-Cured Epoxy, The 25th Annual Meeting of The Adhesion Society, Inc. and The Second World Congress on Adhesion and Related Phenomena (WCARP-II)
(Accessed February 21, 2024)