PHOTO DYNAMIC-MECHANICAL ANALYSIS FOR CORE MONITORING OF FIBER-REINFORCED PHOTORESIN COMPOSITES

The use of phot dynamic mechanical analysis (photo DMA) si discussed f or cure monitoring of fiber reinforced photoresin composites. In the p hoto DMA technique, the uncured fiber/resin suspension is dispensed on to a low-modulus elastomeric substrate. The force needed to impose a dynamic elongation is recorded continuously while the sample is cured by ultraviolet radiation. The influence of glass, quartz, and carbon f ibers on the photocure of polyacrylate resins was determined by the ph oto DMA technique. Glass and quartz fibers were found to have no detec table effect on the cure kinetics of photoresins, whereas carbon fiber s were found to inhibit the cure significantly. A static as well as a dynamic finite element analysis was used to calculate the modulus of t he cured composite from the results of the phot dynamic mechanical ana lysis.