Quality improvement from functionalized tire rubber

The Tire and Specialty Rubbers (TSR) business unit of specialty chemicals company LANXESS showcased its latest developments for the tire industry at the Tire Technology Expo held in Hanover on February 16 to 18. The focus of this year’s talks by the experts at LANXESS centered on the opportunities and possible improvements resulting from functionalized tire rubber, such as S-SBR and NdBR. At the expo, LANXESS expert Thomas Ruenzi also gave a detailed presentation on this topic. A further presentation by LANXESS process specialist Saeid Kheirandish looked at the compound properties of NdBR rubber, which play a particularly important role in the production of high-performance tires.

New approaches, initial results

One approach for improving existing tire rubber compounds that is the constant focus of widespread discussion in the industry is identifying functionalized rubber that can help, for example, to further optimize the interaction between polymer and fillers. LANXESS is working on new solutions in this field. “This is a challenge that many users of synthetic rubber underestimate. You see, it isn’t easy to functionalize Ziegler-Natta rubber at all,” states Dave Hardy, an experienced tire rubber specialist at TSR.

Following LANXESS’ market launch of successfully functionalized S-SBR rubber grades under the name Buna FX, a number of new variants are currently being tested. This is the subject of a further LANXESS contribution to the Tire Technology Expo’s conference program – “In-chain and chain-end functionalized S-SBR and NdBRs for green tire applications” – by product developer Ruenzi, which expressly moves beyond chain-end functionalized rubber to also include variants with functional groups that are distributed along the polymer chain. By their very nature, the density of potential anchor points in these rubber grades is higher than in the standard chain-end functionalized variants. In a complex study, LANXESS chemists ascertained the properties silica compounds obtain from the new, differently functionalized S-SBR rubber – including in various combinations. Ruenzi will also be describing initial tests on the company’s multi-functionalized NdBR rubber.

The second LANXESS presentation, by experienced rubber expert Kheirandish, demonstrated that TSR’s support for processors extends beyond the further development of raw materials to also include process optimization. “New insights into processing of neodymium-based rubber grades by LANXESS” reports on his investigations into the compound properties of the NdBR grades Buna CB22 and Buna Nd22EZ – paying special attention to the development of the compound’s Mooney viscosity during processing. Kheirandish sheds particular light on the compound properties of the NdBR variants used in combination with natural rubber and the process temperature. Buna CB22 and Buna Nd22EZ are frequently used in tire compounds to achieve good performance combined with low rolling resistance.

“Current innovations relate above all to applications and process developments. This presentation shows what LANXESS has to offer besides high-performance polymers,” according to Mr. Hardy. “Our outstanding expertise benefits the tire sector in particular, which makes me confident that – as in previous years – we’ll come up with a whole host of new approaches in 2016 that will be just what the industry is looking for. I’m also looking forward to the feedback during the specialist discussions at the expo.”

LANXESS is a leading specialty chemicals company with sales of EUR 8.0 billion in 2014 and about 16,300 employees in 29 countries. The company is currently represented at 52 production sites worldwide. The core business of LANXESS is the development, manufacturing and marketing of plastics, rubber, intermediates and specialty chemicals.