Abstract The foundation for the Army's Research and Development Program is based upon the requirements of the tactical and support forces. In meeting hardware requirements and in our attempts to obtain significantly improved weaponry and equipment, we are continually searching for new materials. Many materials needed by the Army must possess special combinations of properties not required in normal commercial use. Military operations are today expected to take place at temperatures down to − 50° F. and much of our equipment is frequently exposed to even lower temperatures. Such low temperatures are found not only in the Arctic, but − 70° F. is a common summer temperature encountered by jets, missiles and their working component parts, only a few miles from the surface of the earth. At the other extreme, ground temperatures of 120° F. are common in various parts of the world and temperatures of 1,000° F. are encountered in many operating components of military equipment. During World War II, in Alaska and the Aleutians, and later in Korea, the hard lesson was learned that commercially available rubbers were not completely satisfactory for use in many military items. Fuel lines and pump diaphragms failed because of embrittlement; rubber covered cables and wires froze and broke on handling or lost electrical insulating properties; chemical warfare protective clothing and gas masks became stiff and unusable; tires developed flat spots; tubes buckled and stiffened; and many gaskets failed to perform their function. Indeed our whole bulk handling system for fuels and petroleum is dependent upon the proper functioning of rubber gaskets in couplings and in rubber fuel lines, containers and liners. In the last ten years, operational requirements for rubber have drastically changed. Nevertheless, rubber is still considered the best fabrication material for containing POL (petroleum, oil and lubricants) chemicals, whether it is a gasket or a 10,000 gallon flexible container. Rubbers are currently needed that, in addition to the already listed requirements, must also be resistant to concentrated acids, propellants and strong oxidizers. Further, it is desirable to have elastomers with high resistance to the effects of flame for use in compounds that may be exposed to short impulses of high intensity heat and radiation. Elastomers with satisfactory properties in one degree normally fail in others. To develop elastomers with the best possible combination of properties has been the goal of our elastomer research program since its inception.
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Feb 1, 1967
C B Griffis + 1