Full definition
Polychloroprene (CR) compound used as the body (matrix) material in power transmission belts, serving as the structural medium surrounding and bonding the tension cords while providing the grip surface in pulley grooves. Neoprene was the dominant belt body compound from the 1950s through the 1990s due to its balanced resistance to mineral oils, moderate heat (up to 90°C continuous), ozone, and cyclic flexing fatigue. Properties: hardness 55-75 Shore A, excellent dynamic fatigue life (millions of flex cycles), moderate oil resistance (resists incidental contact with lubricants and greases), flame retardancy, and good adhesion to polyester, aramid, and fiberglass tension cords. Since the 2000s, EPDM has largely replaced neoprene for standard drives due to 20-40% longer service life and better heat resistance in clean environments. However, neoprene remains mandatory for drives in oily environments (metalworking, food processing with fats, automotive engine bays with oil mist). Belt manufacturers using CR compounds: Gates, Continental, Optibelt, Mitsuboshi. Per ISO 1813 for belt material classification.