Evaluation of mechanical properties of advanced polymers for composite cryotank applications

Composite materials are actively being used in the aerospace industry as a means of reducing weight. In particular, polymer matrix composites (PMC) are good candidates due to their high strength-to-weight and stiffness-to-weight ratios. A fundamental step to understand how a PMC will behave in a cryotank’s extreme environmental is to first understand how the constituents (namely, the polymer matrix) behave in that same environment. Therefore, both stress-based and fracture-based experiments were conducted to evaluate four candidate polymers supplied by NASA Langley Research Center. Each type of test was conducted at approximately −196°C (−320°F), 24°C (76°F), and 160°C (320°F). Based on the results of the four polymer systems, a recommendation as to the best candidate for polymer matrix and adhesive bonding for Reusable Launch Vehicle’s (RLV’s) composite cryotanks is made.