Epoxy Cure Monitoring at the Fiber/Matrix Interfaces Using Fiber-Optic EvanescentFluorimetry

摘要

It has been demonstrated earlier that epoxy cure reactions can be monitored byfluorescence excitation peak shift of the curing agent, such as diaminodiphenylsulfone (DDS), during reaction, In-situ cure monitoring can be made via a fiber-optic probe embedded in the matrix or in composites. The 'evanescent mode' optical fiber provides a novel approach for monitoring the cure of epoxy at the fiber/resin interphase in 2000 angstroms thickness. A high numerical aperture, high refractive index, optical fiber has been used to prepare an evanescent mode optical fiber probe and application of the probe for cure monitoring was demonstrated using a neat epoxy system. Present work is focused on demonstrating the ability of this technique to monitor the effect of modified glass surface on the cure reaction of epoxy at the interphase, which differs not only from its bulk behavior but also varies depending on the nature of fiber surfaces.