Chloroprene rubber (CR) is more commonly know by the trade name Neoprene®.
Chloroprene is unusual in that it is moderately resistant to both petroleum oils and weather (ozone, sunlight, oxygen). This qualifies Neoprene® for O-ring service where many other elastomers would not be satisfactory. It is also used extensively for sealing refrigeration fluids. FDA grades are available. Neoprene has good compression set characteristics, abrasion resistance, and a temperature range of -65° to 285°F (-55° to 140°C).
PAI offers Neoprene® compounds in a hardness range of 40 to 90 durometer. Black is the standard color, but many other colors are available.