Kuraray Co., Ltd. today announced the development of the SEPTON V Series, hydrogenated styrenic thermoplastic elastomers (hereafter, "hydrogenated styrene elastomers") that will provide compounds with improved heat resistance and oil resistance.
Typical hydrogenated styrenic elastomers are composed of hard blocks (styrene) and soft blocks (ethylene, propylene, butylene, etc.) polymers. As with other plastics, they are easily processed when heated. These elastomers also have the elasticity of rubber, which allows them to be used as a substitute for vulcanized rubber and flexible polyvinyl chloride. The world market for hydrogenated styrene elastomers is approximately 100,000 tons per year, with a growth rate of approximately 10% per year (Kuraray estimate). These resins are easily compounded with polypropylene, process oil and other ingredients, or can be dynamically cross-linked in the compounding process. However, when these resins are cross-linked, only the soft blocks cross-links, which means that the heat and oil resistances are limited. Markets in which these characteristics are important still use vulcanized rubber.
Unlike earlier SEPTON products, the SEPTON V Series contains a crosslinkable hard blocks and makes it reactive. Kuraray has also developed special compounding technology which makes it possible to cross-link the hard blocks as well as the soft blocks during compounding. This provides a compound with higher heat and oil resistance, which makes them suitable for use in markets in which vulcanized rubber is used such as automotive sealing material and construction materials.
Kuraray is scheduled to commence production of the SEPTON V Series in the summer of 2004. The new product will be marketed together with the compounding technology Kuraray has developed. As various compounders combine Kuraray's compounding technology with their own, it can be expected that development will accelerate and the number of applications will increase. For this reason, Kuraray will maintain close ties to these compounders, and hopes to nurture this market in the near future to the scope of 5,000 tons per year. With this new material as a core product, Kuraray will work to expand its elastomer business.
Vulcanized rubbers are made from both natural and synthetic rubber, the latter including diene rubber, acrylonitrile-butadiene rubber (NBR), and ethylene-propylene-diene polymers (EPDM). The annual world market for vulcanized rubber is 15 million tons (Source: International Institute of Synthetic Rubber Producers, Inc.).
The improved heat resistance and oil resistance, as well as the processability of the SEPTON V Series will allow them to compete in previously unattainable vulcanized rubber markets, such as automotive and machinery parts and construction materials. It is estimated that the size of this market will be approximately 500,000 tons annually.