Hybrid filler system for nitrile rubber vulcanizates

Relative efficiency of different types of fillers e.g., phenolic resin, car bon black and carbon black plus phenolic resin hybrid system in nitrile rub ber vulcanizates for improvement of physico-mechanical properties, resistan ce to swelling in oil/fuel and thermal stability has been studied. The hybr id system was always found to offer maximum benefit in strength and dynamic mechanical properties coupled with higher percent of (a) retention of phys ical properties due to aging and (b) swelling resistance in oil or fuel. Bo th thermogravimetric analysis (TGA) as well as thermomechanical analysis (T MA) reflect much better thermal stability for the combined filler system co mpared to the vulcanizates containing either phenolic resin or carbon black . (C) 2001 Kluwer Academic Publishers.