Full definition
Expanded polychloroprene (CR) foam with individually sealed (closed) gas cells that make the material waterproof, dustproof, and buoyant while providing excellent thermal insulation, cushioning, and compressible sealing properties. Per ASTM D1056 classification: 2A1 (firm, 25% compression deflection 15-80 kPa), 2A2 (medium), 2A3 (soft). Density: 80-250 kg/m³. Thermal conductivity: 0.04-0.06 W/m·K (good insulator). Temperature range: -40 to +105°C. Key properties: waterproof (sealed cells do not absorb water), excellent ozone and UV resistance, inherent flame retardancy (self-extinguishing — oxygen index >26%), moderate oil resistance, and good vibration damping. Applications: diving wetsuits (3-7 mm, the iconic application — insulates by trapping nitrogen in cells), HVAC duct insulation and sealing, outdoor electrical enclosure gaskets, marine hatch seals, pipe insulation, laptop and tablet sleeves, orthopedic braces, and general-purpose weather sealing. Available as sheets (1,300 × 2,000 mm typical), rolls, die-cut parts, and adhesive-backed tapes. Brands: Rubatex, Den-Wal, Armacell (AP Armaflex). Competes with closed-cell EPDM foam (better weathering) and PVC/nitrile foam (more economical).