Dominant formation of disulfidic linkages in the sulfur cross-linking reaction of isoprene rubber by using zinc stearate as an activator. Issue 20 (19th March 2018)

• Record Type: Journal Article
• Authors: Sakaki, Yuta; Usami, Ryota; Tohsan, Atitaya; Junkong, Preeyanuch; Ikeda, Yuko
• Is Part Of: RSC advances. Volume 8:Issue 20(2018)
• Page Start: 10727
• Page End: 10734
• Publication Date: 2018-03-19
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c8ra00544c
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : The bridging bidentate zinc/stearate complex, an intermediate for the sulfur cross-linking reaction, supposedly induces an abundance of disulfidic linkages in the rubber network. Abstract : A linear combination fitting in sulfur K-edge X-ray absorption near edge structure (S-XANES) measurements reveals each fraction of monosulfidic, disulfidic and polysulfidic linkages in solvent extracted sulfur cross-linked isoprene rubbers. The sulfidic linkage of a disulfidic type is found for the first time to be dominant when zinc stearate and N -(1, 3-benzothiazol-2-ylsulfanyl)cyclohexanamine are used as the activator and accelerator, respectively, for the sulfur cross-linking reaction at 140 °C. The presence of the bridging bidentate zinc/stearate complex as an intermediate for the sulfur cross-linking reaction is supposed to induce the generation of abundant disulfidic linkages in the rubber networks. This unexpected observation is of use for the material design of high performance rubber products with anti-aging and thermal stabilities. S-XANES is a powerful tool that was used to reveal the characteristics of the sulfur cross-linking of rubber. These results will contribute to the development of rubber science and technology.