Use Of Dynamic Mechanical Analysis in Thermoset Resin Development (For Composites Applications)

摘要

DMA is compared to DSC as a method of thermal analysis and materials characterization. The basic instrument parameters are briefly described, as well as their influence on the data collected. The glass transition temperature, T_g, in polymers can be defined in several ways from DMA data. These are compared with T_g assignments made from DSC and in relation to the heat deflection temperature. DMA samples are much larger than those used in DSC, making their measured properties more representative of the bulk properties in heterogeneous materials. Examples of evaluating solid and liquid samples of thermoset resins are illustrated. The relationship between resin cure conditions, the degree of cure and ultimate cure, as measured by T_g, is related through first principles to molecular motions in adhesive and structural laminate resins. Finally, a novel technique is described which can be used to assess the effects of resin structural changes on adhesive performance.