TOKYO — Specialty chemicals producer Kuraray Co. Ltd. has developed a reactive liquid rubber that it claims can be used in tread compounds to enhance the ice-grip performance of winter tires.
The material, liquid farnesene rubber (LFR), is described as a diene monomer developed in partnership with U.S. biotech company Amyris Inc. through the fermentation of sugar cane.
Sumitomo Rubber Industries Ltd. (SRI) is using the material as a performance-enhancing additive in a studless winter tire, the Dunlop Winter Maxx 02, that it's marketing in Japan, where the use of studded winter tires is highly restricted.
The Winter Maxx 02 uses LFR in compounds that yield improved ice-grip performance at low temperatures, Tokyo-based Kuraray said, while also impeding the hardening of rubber compounds over time,
When used as an additive in rubber compounds, LFR shows high plasticity while still maintaining "excellent flexibility even at low temperatures and improves ice grip performance," the company added.
"Due to its optimal molecular weight," Kuraray said, "LFR reacts completely with solid rubber during vulcanization, meaning, unlike an oil — which would migrate to the rubber's surface over time and thus impede hardening — it stays bonded. Therefore, its ice-grip performance is maintained over the long term."
Sumitomo has applied for a patent on the use of LFR in tire compounding for a studless winter tire.
While Sumitomo has demonstrated the viability of this application, Kuraray is looking beyond tire applications for this unique material, according to Erich Klein, elastomers business unit marketing manager for Kuraray America Inc.