Process Control Analyzer for High Elastic Modulus Composites

"The overall goal of this proposed program is to develop fiber optic Raman spectroscopy as an on-line analyzer capable of optimizing the mechanical properties of composites during manufacture. Phase I will demonstrate feasibility by developingrelationships between reaction mechanisms measured by Raman spectroscopy and mechanical properties measured by rheology for epoxy resin as a model system, with a focus on glass transition temperature and elastic modulus. This will be accomplished by 1)measuring during-cure molecular properties that correspond to specific cure mechanisms, associated rate constants, and extent-of-cure by Raman spectroscopy, 2) measuring post-cure macroscopic properties that correspond to glass transition temperature andelastic modulus by dynamic mechanical methods, and 3) performing simultaneous Raman spectral and shear moduli measurements in a parallel-plate rheometer to link the in-cure molecular to post-cure macroscopic properties.Phase II will employ the Phase I relationships to control composite manufacture devices and composite properties. Measurements will be performed in an oven used to cure filament wound parts, an autoclave, and a resin transfer molding device. Phase IIwill expand the relationships developed in Phase I for epoxy resins to include polyimides, polyesters, and cyanate esters. Phase III will develop an expert system based on customer product base. In addition to military applications, th