(2658)MONITORING OF AGING OF AN OUT-OF-AUTOCLAVE PREPREG USING DIFFERENTIAL SCANNING CALORIMETRY

摘要

Recent advances in prepregs have enabled oven curing to achieve high quality parts at lower temperature compared to autoclave curing. In aerospace applications, multiple rolls of prepreg are often used to manufacture large parts and the material may remain outside several days during fabrication. As such, it is always a concern that the part's quality could be affected due to material aging during out-time under ambient conditions. Although the reaction is more progressive at elevated temperature, extended out-time at lower temperature could also build up problems, such as decrease in tackiness and processability of prepreg. In this paper, a differential scanning calorimeter was utilized to study aging progress of an out-of-autoclave prepreg. It was observed that the sub-ambient glass transition temperature and percent of conversion due to aging increased proportionally with out-time of prepreg. Additionally, total heat of reaction, peak temperature, and activation energy were decreased as out-time increased.