High Temperature, Long Service-Life Fuel Cell Bladder Materials

Fuel bladders are flexible rubber containers that are used to store fuel within aircraft structures. Higher performance aircraft use the fuel as a circulating cooling fluid which results in heated fuel being returned to the bladder. Accelerated aging of the bladder and failure of the bladders in being observed in the field as a result of the elevated temperature of the fuels being returned. Temperatures of over 200 degrees F have been observed in the field and higher temperatures are predicted in future designs. The current fuel bladder material technology cannot be modified to withstand these temperature requirements. Under the proposed program, METSS Corporation will develop improved formulations of bladder materials suitable for service with fuels up to temperatures of 250 degrees F. Development efforts will focus on exploiting fluorinated urethanes, highly saturated nitrile rubbers, improved nitrile formulations, and epichlorohydrin rubbers. A focused failure analysis effort will be conducted during the program and the results used direct program development efforts..