Published April 2014
Styrenic block copolymers (SBCs) are the largest-volume market of the family of thermoplastic elastomers (TPE). TPEs have rubberlike properties, but process as thermoplastics. As with other thermoplastic elastomers, styrenic block copolymers are characterized by their ability to be processed as thermoplastic materials while possessing the physical and mechanical properties characteristic of filled vulcanized elastomers. In addition, the scrap generated is reprocessable. These factors combine to reduce the production cost of finished articles based on these materials, compared with vulcanized rubber. Styrenic block copolymers exhibit good elastic qualities, but display lower elastic recovery than standard rubbers. Also, they demonstrate good flexibility at lower temperatures but their use is limited at higher temperatures because of their relatively low softening points.
There are three major types of SBCs:
- Styrene-butadiene-styrene (SBS) block copolymers
- Styrene-isoprene-styrene (SIS) block copolymers
- Hydrogenated styrenic block copolymers (HSBC)
The following pie chart shows world consumption of styrenic block copolymers:
By the end of 2013, the six largest producers—Lee Chang Yung, Sinopec, Kraton, TSRC, Dynasol Elastómeros and Versalis (formerly known as Polimeri Europa)—owned 69% of global SBC production capacity. Today, Lee Chang Yung owns the largest production capacity for SBCs, ahead of Sinopec and Kraton. However, Kraton is still the most important global supplier of SBCs worldwide. It has significant market shares in all world regions, whereas Sinopec is still predominantly present in China and Lee Chang Yung in Asia.
In recent years, China has become the largest world market for styrenic block copolymers, surpassing North America and Europe. China is the leading footwear producer in the world, followed by India, and this industry consumes vast amounts of rubber and elastomers, including styrenic block copolymers (especially SBS).
After recovery from the economic crisis in 2008–2009 and the southern European sovereign debt crisis in 2012–2013, the European economy started to grow again in the second half of 2013. Consumption of SBCs in all regions is forecast to grow, although the growth rate is declining with the maturity of the markets. The decline of the footwear market, with its shift to low-labor-cost areas, has affected Western Europe the most, but even in China demand from this industry is growing at a slower pace.
Global consumption of SBCs is expected to grow at an average annual rate of 3–4% during 2013–2018. In the developed regions, consumption will be driven by SBC use in the compounding and adhesives and sealants markets. In Asia (excluding Japan), polymers and asphalt modification, as well as compounding, will drive consumption, as consumption growth in footwear has slowed considerably. Central and Eastern Europe has become an interesting market, with overall demand forecast to grow at an average annual rate of 8–9% (driven predominantly by paving in Russia) through 2018, even faster than in China.