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Oxidation of butadiene polymers

1968; Wiley; Volume: 24; Issue: 1 Linguagem: Inglês

10.1002/polc.5070240126

1935-3065

E. M. Bevilacqua,

Polymer composites and self-healing

Abstract Butadiene polymers and copolymers undergo both scission and cross‐linking during thermal oxidation, the scission exceeding the crosslinking by a small amount. As a result initially soluble polymer develops gel and insoluble polymer develops sol. A limiting solubility is reached rapidly. This affords a quantitative estimate of the scission‐to‐cross‐linking ratio. Vulcanization with sulfur and accelerators causes a much more complex change on oxidation, not easily described by solubility analyses. Reaction with sulfur causes an excess of crosslinking over amount of scission during oxidation. Formic acid is a major low molecular weight product of oxidation. Higher molecular weight fragments include acetone and acetaldehyde; others have not been identified. These products do not provide the helpful clues to the oxidation mechanism afforded, for example, by levulinaldehyde in the case of polyisoprene.