DID YOU KNOW? DTIC has over 3.5 million final reports on DoD funded research, development, test, and evaluation activities available to our registered users. Click HERE
to register or log in.
EXPANDABLE WING TANK STRUCTURES UTILIZING THE SECOND-ORDER TRANSITION TEMPERATURE OF POLYMERIC MATERIALS.
MONSANTO RESEARCH CORP DAYTON OH DAYTON LAB
This report concerns the demonstration of a new feasibility concept for fabrication of expandable, self-rigidizing structures, more particularly its application to F105 wing tanks. The concept is based on a fundamental property of all polymeric materials, e.g., polymeric materials change from rigid glassy substances when below the Second Order transition temperature to flexible rubbery substances as the temperature is raised above this transition temperature. The theoretical basis for the concept is discussed and the validity demonstrated on relatively simple structures. An extensive study of resins was made to find those suitable for this application. Several thermpolastic polymers were found that were useful over the temperature range 100 to 290 C. A number of lightly cross-linked epoxy resins were found which gave resins rigid at room temperature 25 C while sufficiently flexible at 100-200 C to be useful in building subscale model tanks. Design considerations are discussed concerning the problem of building a collapsible tank. Work leading to a number of subscale model tanks is described. These tanks had good strength at room temperature and were sufficiently flexible at 100-120 C to collapse to a small volume. On reheating , the collpased model tanks returned to their original shape and volume without use of inflating pressure. Author
Final rept. Jan-Dec 65,