Effect of Reversible Addition-Fragmentation Transfer Emulsion Styrene Butadiene Rubber (RAFT ESBR) on the Properties of Carbon Black-Filled Compounds

• Published in: Polymers Vol. 12; no. 4; p. 933
• Main Authors: Hwang, Kiwon, Mun, Hyunsung, Kim, Wonho
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 17.04.2020; MDPI
• Subjects: Abrasion resistance; Addition polymerization; Automotive parts; Butadiene; Carbon; Carbon black; carbon black-filled compound; crosslink density; Crosslinking; Density; Dispersion; Emulsion polymerization; emulsion styrene-butadiene rubber; Energy dissipation; Energy efficiency; Fragmentation; Free radicals; Fuel consumption; Fuel economy; Molecular weight; Molecular weight distribution; Polymerization; Polymers; RAFT polymerization; Rubber; Styrenes; Tires; Viscoelasticity; vulcanizate structure; vulcanizate structure; crosslink density; emulsion styrene-butadiene rubber; RAFT polymerization; carbon black-filled compound
• ISSN: 2073-4360; 2073-4360
• DOI: 10.3390/POLYM12040933

Tread is an important component that directly affects the performance of passenger car radial (PCR) tires. Styrene-butadiene rubber (SBR) is mainly used for tire tread and it includes solution styrene-butadiene rubber (SSBR) and emulsion styrene-butadiene rubber (ESBR). Although SSBR is mainly used, the manufacturing process for SSBR is more challenging than ESBR, which is environmentally friendly, but has the disadvantage of a broad molecular weight distribution. To overcome this, a reversible addition-fragmentation radical transfer (RAFT) polymerization technique is used in ESBR polymerization. An environmentally friendly RAFT ESBR with a narrow dispersity can be polymerized. Here, carbon black-filled compounds were manufactured while using RAFT ESBR, and their properties were compared to ESBR. The analysis showed a low crosslink density of RAFT ESBR, due to the high polysulfide crosslink structure. We manufactured a carbon black-filled compound with the same crosslink density and structure as the ESBR carbon black-filled compound, and the effect of the dispersity of the base polymer was investigated. RAFT ESBR showed 9% better abrasion resistance and 29% better fuel efficiency than ESBR, according to the analysis of the data. The narrow dispersity can reduce energy loss and positively influence the abrasion resistance and fuel efficiency.