page_title: Polysulfide
section_title: Polysulfides in vulcanized rubber
hierarchical_section_title: Polysulfide / Organic polysulfides / Polysulfides in vulcanized rubber
caption_attribution_description: English: Schematic Structure Example of the Vulcanization_of_POLYIsoprene with n = 0, 1, 2, 3 ... Deutsch: Ausschnitt aus einem schematischen Formelausschnitt von vulkanisiertem_POLYIsoprene mit n = 0, 1, 2, 3 .....
context_page_description: Polysulfides are a class of chemical compounds containing chains of sulfur atoms. There are two main classes of polysulfides: anions and organic polysulfides. Anions have the general formula S²⁻
  ₙ. These anions are the conjugate bases of the hydrogen polysulfides H₂Sₙ. Organic polysulfides generally have the formulae RSₙR, where R = alkyl or aryl.
context_section_description: Many commercial elastomers contain polysulfides as crosslinks. These crosslinks interconnect neighboring polymer chains, thereby conferring rigidity. The degree of rigidity is related to the number of crosslinks. Elastomers therefore have a characteristic ability to "snap back" to their original shape after being stretched or compressed. Because of this memory for their original cured shape, elastomers are commonly referred to as rubbers. The process of crosslinking the polymer chains in these polymers with sulfur is called vulcanization. The sulfur chains attach themselves to the "allylic" carbon atoms, which are adjacent to C=C linkages. Vulcanization is a step in the processing of several classes of rubbers, including polychloroprene (Neoprene), styrene-butadiene, and polyisoprene, which is chemically similar to natural rubber. Charles Goodyear's discovery of vulcanization, involving the heating of polyisoprene with sulfur, was revolutionary because it converted a sticky and almost useless material into an elastomer which could be fabricated into useful products.
caption: Idealized structure of two strands (blue and green) of natural rubber after vulcanization with elemental sulfur, which forms polysulfide linkages.
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