Syntheseal non-asbestos gasket materials are designed to be a direct substitute for asbestos-containing materials. Style 0S8091 is a reinforced cellulose fiber with a Controlled Swell Latent Cure Styrene Butadiene binder. Controlled Swell materials are Latent Cure products which use Styrene Butadiene Rubber (SBR) binders. Significant THK increase occurs at the exposed initial edge of the gasket with many fluids, dramatically improving sealability. The heat of application then vulcanizes the material to limit further swelling and provide fully cured performance.