Natural rubber products appeared in the early 1800s, but were impractical due to softening or brittleness in hot or cold weather. An American inventor Charles Goodyear developed the vulcanization process for natural rubber in 1839, linking unsaturated bonds by sulfur. This basic process is still used with addition of chemical accelerants and stabilizers. By 1945, synthetic rubber was being commercially produced as a rubber substitute.
As tire demand increased, improvements including using an inner tube to replace solid rubber tires, reinforcing with a natural or synthetic fabric cord for strength, and adding materials for reduced wear. Tubeless tires debuted later.
Process of vulcanization on molecular level (shown through chemical symbols)