Neoprene and natural rubber are both polymers, although neoprene is synthetic. Natural rubber is extracted from a tree and is sensitive to temperature changes. Heavy demand led to the development of synthetic materials like neoprene, with similar but superior properties.
Natural rubber came into widespread use in the 19th century for products such as tires, waterproof fabrics and boots, according to the International Institute of Synthetic Rubber Producers. The rubber was found to become brittle in cold weather and sticky in hot weather.
Vulcanization refers to a process which forms crosslinks of sulfur in rubber. According to the website American Chemistry, it makes neoprene stronger, more elastic and more resistant to heat as well as oil, solvents and water.
Neoprene is used for many things including footwear, wetsuits, adhesives and asphalt products. The number of sulfur cross-inks between the chloroprene molecules in neoprene alters its hardness and strength, resulting in different products for different uses.