A novel reprocessable chloroprene rubber based on dynamic disulfide metathesis

• Published in: International journal of smart and nano materials Vol. 15; no. 1; pp. 42 - 61
• Main Authors: Jiang, Jianliang, Zhai, Junxue, Chen, Yanqing, Zhao, Dongqi, Feng, Yakai
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis 02.01.2024; Taylor & Francis Ltd; Taylor & Francis Group
• Subjects: Allyl chloride; Chloroprene rubber; Crosslinking; disulfide; Exothermic reactions; Low temperature; Menschutkin reaction; Metathesis; New technology; Recyclability; reprocessable; Reprocessing; Rubber; Stability; Tensile strength; Vulcanization
• ISSN: 1947-5411; 1947-542X
• DOI: 10.1080/19475411.2023.2258830

For sustainable application of chloroprene rubber (CR), a new technology is developed by the vulcanization of CR using 2,2'-dithiodipyridine (DPD) as a cross-linking agent with the reprocessing performance owing to disulfide metathesis. When DPD was incorporated into CR vulcanization, the Menschutkin reaction between allyl chloride group and pyridine group occurred with a maximum exothermic peak at 184°C. The number of effective cross-linking bond at 0.5 phr DPD vulcanizate was higher than that at high DPD content. This vulcanizate showed high tensile strength (11.12 MPa) and elongation at break (1253 ± 120%) owing to the exchangeable disulfide bond in the system. Under the catalysis of triphenylphosphine, the metathesis of disulfide compound was improved obviously, which endowed CR/DPD vulcanizates with good recyclability performance. Disulfide cross-linkage maintains its stability at low temperature, thus ensuring the mechanical stability of CR/DPD vulcanizate under the ambient conditions. Vulcanization and reprocessing of CR/DPD vulcanizate can be conducted with common industrial rubber processing equipment. Such reprocessable chloroprene rubber could have potential application in CR industry, also serve to significantly improve environmental sustainability.