1. Charles Macintosh: In 1823, Charles Macintosh, a Scottish chemist, discovered that naphtha (a solvent derived from coal tar) could dissolve raw rubber, creating a waterproof material. He patented this process and developed a range of products such as raincoats and umbrellas.
2. Thomas Hancock: Another Scottish chemist, Thomas Hancock, independently discovered the ability of sulfur to improve the properties of rubber. He obtained a patent for his findings in 1843.
3. Charles Goodyear: In the same year, American inventor Charles Goodyear conducted extensive experiments with rubber and sulfur, eventually discovering the optimal combination and temperature for vulcanization. He obtained a patent for his process in 1844.
It's worth noting that while Goodyear is often credited as the inventor of vulcanization, his contributions built upon the earlier work of Macintosh and Hancock. The term "vulcan" itself was coined by Goodyear as a reference to the Roman god of fire, Vulcan.
The development of vulcanization revolutionized the rubber industry and led to the widespread use of rubber in various applications, including tires, hoses, belts, and a multitude of other products.