Effect of bulky 2, 6-bis(spirocyclohexyl)-substituted piperidine rings in bis(hindered amino)trisulfide on thermal healability of polymethacrylate networks. Issue 23 (11th October 2021)

• Record Type: Journal Article
• Authors: Aiba, Motohiro; Koizumi, Take-aki; Okamoto, Kazuaki; Yamanaka, Motoshi; Futamura, Michinari; Ishigaki, Yuzo; Oda, Mitsuo; Ooka, Chihiro; Takahashi, Akira; Otsuka, Hideyuki
• Is Part Of: Materials advances. Volume 2:Issue 23(2021)
• Page Start: 7709
• Page End: 7714
• Publication Date: 2021-10-11
• Subjects: 620.11
• DOI: 10.1039/d1ma00811k
• Languages: English
• ISSNs: 2633-5409

Abstract

Abstract : Bulky 2, 6-bis(spirocyclohexyl)-substituted piperidine rings in bis(hindered amino)trisulfide affords low chain-transfer constant and thermal healability at moderate temperature. Abstract : This paper describes the synthesis of highly sterically hindered piperidinyl trisulfide with four spirocyclohexyl moieties, bis(2, 6-bis[spirocyclohexyl]piperidine-1-yl)trisulfide (BIBSCPS-S3), from commercially available starting materials in short steps and its application as a dynamic covalent bond for thermally healable polymer networks. Conformational study on the BIBSCPS-S3 moiety in the solid state is performed by single-crystal X-ray diffraction. In bulk, a stress-relaxation experiment reveals that the increase in steric hindrance can not only decrease the activation energy for thermal exchange reactions but also suppress chain-transfer reactions during radical polymerization to some extent. Therefore, the dynamic cross-linking point containing BIBSCPS-S3 moiety can be efficiently incorporated into polymer networks with ethyl, n -butyl, or n -hexyl methacrylate monomers, which is in good accordance with the relatively low chain-transfer constants of the BIBSCPS-S3 moiety determined by the Mayo equation. As a result, BIBSCPS-S3-cross-linked poly( n -hexyl methacrylate) exhibits nearly quantitative damage healability only by simple hot pressing at 90 °C under mild pressure for 24 h.