Functionally Graded Adhesives via High-Energy Irradiation
W.Q. Xia, S. Najafian, A.G. Cassano, S.E. Stapleton, and D.F. Schmidt
ACS Applied Polymer Materials, vol. 3, no. 1, pp. 104-109, 2021
A thermally cured epoxy/anhydride system is shown to exhibit dose-dependent increases in cross-link density, glass transition temperature, and modulus. The addition of various sensitizers further boosts sensitivity toward radiation-induced cross-linking. A theory proposed by Shibayama relating T-g with cross-link density provides a useful means to predict the dose at which a particular set of properties may be produced. This combination of an approach to materials formulation and processing and the identification of simple analytical models to predict resultant properties provides a useful strategy for the generation of functionally graded materials.