Fluid Filled O-Rings for Maintaining a Seal Under Low Temperature Conditions

Elastomeric O-rings provide a critical sealing funcion in a myriad of devices of military and commerical interest. A critical problem with currently available O-rings occurs when the O-ring material stiffens at low temperatures, causing a failure in sealing. Previous work by the Army has indicated that a fluid filled O-ring is a viable candidate as a low temperature seal. There is a need to extend this work so that the O-ring will maintain a good low temperature seal and be able to tolerate the high temperatures generated by some applications. In the proposed effort, Texas Research Institute Austin (TRI/Austin) will identify, fabricate, and test different elastomeric skins andliquied cores during the design of a prototype liquid filled O-ring. In order to identify state of the art polymeric materials not currently available in commerical O-rings, TRI/Austin will team with McGahan NuSil, Inc., who are experts in silicones, fluorosilicones and other sealing materials. During the Phase I effort, we propose to investigate and characterize a number of elastomeric materials and liquid filings under high and low tmeprature conditions and examine the interaction between the elastomeric envelope and the liquid filler during the O-ring design process.