Vulcanization is a range of processes for hardening rubbers. The term originally referred exclusively to the treatment of natural rubber with sulfur, which remains the most common practice. It has also grown to include the hardening of other (synthetic) rubbers via various means. Examples include silicone rubber via room temperature vulcanizing and chloroprene rubber (neoprene) using metal oxides.
Worker placing a tire in a mold before vulcanization.
An example of a silicone rubber keypad typical of LSR (Liquid Silicone Rubber) moulding
Rubber, also called India rubber, latex, Amazonian rubber, caucho, or caoutchouc, as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds. Thailand, Malaysia, Indonesia, and Cambodia are four of the leading rubber producers.
Pieces of natural vulcanized rubber at Hutchinson's Research and Innovation Center in France.
Latex being collected from a tapped rubber tree, Cameroon
Rubber tree plantation in Thailand
"Enslaved natives with a load of rubber weighing 75 kilos, they have journeyed 100 kilometers with no food given"