Accelerators critical cure time

Accelerators will also speed gel time, pot life, etc., and they may provide a reaction that is so fast that it is unmanageable. These are critical components that control the curing rate, storage life, and working life of the formulation. An accelerator is often used along with a catalyst, a hardener, or a curing agent, which produces the main polymerization reaction. 

Anhydrides, both liquid and solid, are used widely for curing epoxy resins. The reactivity of some is slow and an accelerator (usually a tertiary amine) is often used at 0.5-3.0% to speed gel time and cure. The optimum amount is usually critical, depending on the anhydride and resin, and the cure schedule. Amounts above or below the correct level will reduce the high-temperature performance. The optimum balance should be established by experiment. Eutectic mixtures to depress the melting points may be prepared. 

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