Originally Posted by FowVay
companies such as Parker sell rubber lubricants specifically for O-rings. If you have rubber exposed to the atmosphere then plain old talcum powder is used by nearly every rubber manufacturer to prolong the life of their product while in storage.
Talcum powder is used for longterm storage of rubber parts because oxidized rubber gets sticky due to devulcanization over time and the talcum powder prevents the rubber parts from sticking, I often feel a greasy type powdered on new rubber parts and that's to the best of my knowledge powdered tallow, which serves likely doube-duty as a lubricant/conditioner and ant-stick agent.