A tire accelerator is a chemical that speeds up the vulcanization of rubber in tires. It’s used in tire compounds to shorten the curing time. Several different types are available, each with its own advantages and disadvantages. The most common accelerator in tire compounds is zinc oxide, which provides good scorch safety and low vulcanization temperature. Other choices include thiazoles, sulfenamides, thiurams and dithiocarbamates. Each offers some advantage over the others, but all must be used within strict limits to avoid problems such as too rapid vulcanization (scorch) or poor crosslink density.