SILICA-REINFORCED ETHYLENE-PROPYLENE DIENE (EPD) RUBBERS
ARMY NATICK LABS MA NATICK
Pagination or Media Count:
High quality ethylene-propylene diene EPD rubber vulcanizates can be produced by using hydrated silica as the reinforcing filler. Modification of EPD rubber by chemical promotors such as p-quinone dioxime and the use of silica activators such as polyethylene glycol gives compounds with an acceptable rate of cure. Hot mastication, especially in the presence of halogenated compounds, gives vulcanizates with good physical properties. Processing aids such as stearic acid may be used, and oilextended EPD rubber is a convenient plasticizer for silicareinforced compounds. To reduce costs, silica fillers can be extended with other such low-cost fillers as hard clay. EPD rubbers may also be blended with other elastomers. High quality silica-reinforced expanded EPD rubbers may be produced by conventional blowing agents and processing techniques. Silica-reinforced EPD rubbers crosslinked with organic peroxides give vulcanizates with good resistance to abrasion and compression set. EPD rubber vulcanizates have excellent resistance to ozone and fungi and, in the presence of ultraviolet screening agents, show good weathering properties.
- Elastomers and Rubber