Antioxidants polychloroprene rubber

Substituted dipyhenylamines 4,4 -Dioctyldiphenylamine (III) Yes Moderate antioxidants. Some use in polychloroprene rubbers. 

Standard-grade PSAs are usually made from styrene-butadiene rubber (SBR), natural rubber, or blends thereof in solution. In addition to rubbers, polyacrylates, polymethylacrylates, polyfvinyl ethers), polychloroprene, and polyisobutenes are often components of the system ([198], pp. 25-39). These are often modified with phenolic resins, or resins based on rosin esters, coumarones, or hydrocarbons. Phenolic resins improve temperature resistance, solvent resistance, and cohesive strength of PSA ([196], pp. 276-278). Antioxidants and tackifiers are also essential components. Sometimes the tackifier will be a lower molecular weight component of the high polymer system. The phenolic resins may be standard resoles, alkyl phenolics, or terpene-phenolic systems ([198], pp. 25-39 and 80-81). Pressure-sensitive dispersions are normally comprised of special acrylic ester copolymers with resin modifiers. The high polymer base used determines adhesive and cohesive properties of the PSA. 

Ethylenethiourea has a wide variety of uses in addition to vulcanization, a principal application since 1948. The curing process converts most of the ETU to other compounds, but traces of it are still found in the rubbers. Neoprene (polychloroprene) is found largely in automotive parts, wire and cable insulation, construction and adhesives. Consumer products containing neoprenes include container seals (e.g., aerosol dispensers) and shoes. It is also an intermediate in the manufacture of antioxidants, dyes, fungicides, insecticides, pharmaceuticals, synthetic resins, and a constituent of plating baths. 

ETU is used as an accelerator in the vulcanization of polychloroprene (Neoprene) and other elastomers for coated fabrics, for epichlorohydrin and for chlorosulfonated polyethylene rubbers. It is also an intermediate for antioxidants, insecticides, fungicides, dyes, pharmaceuticals, and synthetic resins. 

Elastomers include natural rubber (polyisoprene), synthetic polyisoprene, styrene-butadiene rubbers, butyl rubber (isobutylene-isoprene), polybutadiene, ethylene-propylene-diene (EPDM), neoprene (polychloroprene), acrylonitrile-butadiene rubbers, polysulfide rubbers, polyurethane rubbers, crosslinked polyethylene rubber and polynorbomene rubbers. Typically in elastomer mixing the elastomer is mixed with other additives such as carbon black, fillers, oils/plasticizers and accelerators/antioxidants. 

Vulkanox HS is an antioxidant with relatively weak staining and discoloration characteristics, it provides outstanding heat protection in natural rubber (MR), synthetic polyisoprene (IR), polybutadiene (BR), styrene butadiene rubber (SBR), nitrile rubber (NBR) and ethylene propylene rubber (EPIBl), but is less suited>le for polychloroprene (CR). Its performance is improved further in combination with Vulkanox MB-2 antioxidant, which is especially effective in thiuram cured articles with low levels or sulfur or without sulfur. Vulkanox HS antioxidant also yields good protection against rubber poisons. 

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