Estimation of silica flocculation in SBR/BR compounds reinforced with different silica contents from their rheocurves

• Published in: Journal of applied polymer science Vol. 137; no. 15
• Main Authors: Yang, Jae‐Kyoung, Park, Wonhyeong, Ryu, Changseok, Kim, Sun Jung, Kim, Do Il, Seo, Gon, Kim, Jong‐Ho, Chung, Chang‐Bok
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 15.04.2020; Wiley Subscription Services, Inc
• Subjects: applications; Butadiene; composites; Coupling; Crosslinking; Flocculation; Materials science; Polymers; Rubber; Silanes; Silicon dioxide; Tensile properties; Torque
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.48559

ABSTRACT The rheocurves of silica‐filled styrene–butadiene/polybutadiene rubber (SBR/BR) compounds containing 3‐octadecyltriethoxy silane (OTES) and bis‐[triethoxysilylpropyl]tetrasulfide (TESPT) were investigated to examine the effects of silica content and silanes on silica flocculation during mixing and cure. SBR/BR compounds without curatives were also prepared to infer the effect of cure on silica flocculation. The maximum torque of the compounds could be deconvoluted to individual source torques such as silica flocculation during mixing and cure, crosslinking of rubber, and coupling between rubber and silica by assuming the independence of silica flocculation from cure and coupling. Torque due to silica flocculation increased with the silica content of the SBR/BR compounds, but its effect was significantly reduced by the addition of OTES or TESPT. TESPT suppressed silica flocculation and facilitated coupling, thus yielding enhanced tensile properties. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48559. Deconvolution of τmax′ of R‐Sixx‐T compounds with different silica contents to their torquesources