RESISTANCE OF ELASTOMERS TO PROLONGED DEFORMATION UNDER ADVERSE CONDITIONS.

Many rubber products, especially in the field of fluid sealing, are required to function under compression, elongation or shear for very prolonged periods under adverse conditions of temperature, oxidation, moisture, ozone, exposure to fluids and even radiation. Results are presented of recovery from deformation for periods up to one year at temperatures up to 200C and in various adverse environments. In this study a simple modification of the standard compression set method and of the treatment of the data obtained was employed which increases its value for design and prediction purposes, while retaining its essential simplicity. It is shown that from results of tests up to 1000 h duration, useful predictions of long-term behavior can be made, in a more useful form for designers than conventional set data.