Composite Interphase Study by Evanescent Fiberoptic Fluorescence

摘要

UV-Vis fiber optic fluorimetry has been utilized for in-situ monitoring of epoxycure kinetics. This work included the extrinsic fluorescence dye labelling approach as well as the intrinsic fluorescence method in which the fluorescence of the curing agent such as diaminodiphenylsulfone (DDS) itself is monitored. The evanescent wave provides a unique opportunity for studying the cure of fiber reinforced composites at the epoxy/fiber interphase. Sapphire optical fibers are used for evanescent wave sensing because of their high refractive index, UV-Vis transmission and good thermal properties. In order to demonstrate operation of the probe in the evanescent mode a polymer cladding was applied to a portion of the fiber. In order to maximize the fluorescent intensity, the fiber tip was metallized and fiber diameter was optimized. Ongoing work aims at studying the effect of surface modification and composite cure monitoring in the interphase. jg.