a1 Division of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138
a2 Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138
A superlayer test has been adapted for the measurement of the fracture energy between epoxy thin films and self-assembled monolayers (SAM's) on Au/Ti/Si substrates. The “arrest” mode of analysis has been shown to provide consistent results, particularly when relatively wide lines are used to encourage lateral decohesions. The fracture energy, Γi, of the interface between the monolayer and the epoxy is varied by adjusting the ratio of COOH/CH3 terminal groups. Connections among Γi, the surface energies, and the inelastic deformations occurring in the epoxy are explored upon comparison with interface crack growth simulations.
(Received November 03 1997)
(Accepted February 09 1998)