Unformatted text preview: to steam, hot water, and aqueous acids over those cured with bisphenols. Peroxide-cured compounds generally do not contain much inorganic bases, so they are less susceptible to attack by aqueous fluids. On the other hand, the curing of fluoroelastomers using peroxide requires crosslinking agents (―radical traps‖), and the resulting compounds give lower thermal stability than that cured with bisphenols. For peroxide curing, fluoroelastomers must contain sites reactive toward free radicals, usually bromine or iodine introduced within chains by incorporation of cure-site monomers or at chain ends by chain-transfer agents. In the late 1970s, DuPont offered the first commercial peroxide-curable fluoroelastomers which had a bromine-containing cure-site monomers (i.e., 4-P* + P* P-P (crosslink)...
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- Spring '08
- Polymer, Polymer chemistry, free radicals, Fluoroelastomers, various curing mechanisms