IMPROVED GASKET MATERIALS

IT IS PROPOSED TO ESTABLISH THE FEASIBILITY, AND PREPARE A PROTOCOL FOR SYNTHESIZING AND FORMULATING A NEW IMPROVED SILICONE ELASTOMER MATERIAL FOR USE IN ARMY WEAPONRY PACKAGING. THIS MATERIAL WILL HAVE EXTENDED SERVICE COMPARED TO ELASTOMERS CURRENTLY IN USE FOR THIS PURPOSE, AND PRODUCTION COSTS SHOULD BE REASONABLE. THE BEST MEASURE OF MERIT FOR LONG SERVICE LIFE IS LOW STRESS RELAXATION (AND INDIRECTLY LOW COMPRESSION SET). IT IS PROPOSED TO TEST A BASELINE GASKET MATERIAL FOR STRESS RELAXATION AND COMPARE THIS DATA WITH THREE SPECIALTY SILICONE RUBBERS (WITH CHEMICAL SIMILARITIES TO THE NEW MATERIAL) THAT ARE AVAILABLE IN EXPERIMENTAL QUANTITIES. PHYSICAL PROPERTY CHANGES OF THESE ELASTOMERS WILL BE MEASURED UNDER DIFFERENT DEGREES OF COMPRESSION (DEFLECTION) AT 73 DEGREES F, AS WELL AS HIGH (302 DEGREES F) AND LOW (-40 DEGREES F) TEMPERATURES. USING THE TIME-TEMPERATURE SHIFT METHOD (SUPERPOSITIONING), THE ACCELERATED AGING DATA WILL BE CORRELATED INTO A 73 DEGREE F MASTER CURVE, PROJECTING STRESS RELAXATION FOR SEVERAL YEARS (UP TO 20). THE 73 DEGREES F DATA (ONLY A FEW MONTHS TIME PERIOD IN PHASE I) WILL BE USED TO MAKE A PRELIMINARY ESTIMATE OF THE ADJUSTMENT FACTORS NEEDED FOR USE IN PREDICTING SERVICE LIFE OF ELASTOMERS.