Full definition
A high-performance contact adhesive system consisting of a neoprene base component plus a separate isocyanate (MDI/TDI) hardener/activator. When mixed and cured, the isocyanate cross-links the neoprene adhesive film, providing dramatically improved heat resistance (bond stable to 100-120°C vs 60-80°C for single-component), superior solvent resistance, and higher peel and shear strength. Mix ratio typically 100:3-5 (base:hardener by weight). Pot life after mixing: 4-8 hours. Full cure: 24-72 hours at room temperature. Application: same contact technique as single-component — apply to both surfaces, dry, press together. Two-component systems are specified when bonds will be exposed to elevated temperatures, solvents, or sustained stress. Applications: conveyor belt cold splice repairs, bonding rubber to metal in field conditions, industrial flooring installation with heated equipment, and footwear where heat-setting is used. Brands: Rema Tip Top (SC 4000 + hardener E-40), Bostik, Henkel. Cost: 2-3x single-component but far superior durability.