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SBR is a vulcanizable elastomer made by the copolymerization of butadiene
and styrene. It is the workhorse of the rubber industry, even though some of
its properties do not match those of natural rubber. What it lacks in elongation,
hot tear strength, hysteresis, resilience and tensile strength, it makes up
for in better processability, slightly better heat aging and better abrasion
resistance than natural rubber. Probably the most important factors in the
commercial viability of SBR have been its domestic availability, low cost compared
with those of all other synthetic elastomers, ability to accept high filler
levels, relatively stable price compared with that of natural rubber and overall
properties on a cost/performance basis. Principal applications are in tires
and tire products, automotive parts and mechanical rubber goods.
Styrene-butadiene elastomers are the largest-volume synthetic rubber, accounting
for about 46% of world consumption of synthetic rubber in 2006 according to
the International Institute of Synthetic Rubber Producers. Historically, this
percentage had been steadily declining (it was 57% in 1976) because of the
following major reasons:
The increasing popularity of radial tires, which use less SBR and more natural
rubber (NR) than other tire designs (e.g., bias-belted tires)
Faster growth of other synthetic rubbers as a substitute for SBR (e.g., EPDM,
nitrile and polybutadiene rubbers), especially in nontire applications
As a result, world SBR production and consumption showed little or no growth
in the 1980s and 1990s, but have shown steady growth since 2000 with consumption
steadily increasing as a result of growing consumption in emerging regions
(such as China, India, South America, Russia and Other Asia).
The following pie chart shows world consumption of SBR:
North America (United States and Canada) is the only region in the world that
is expected to see a decrease in SBR consumption in the forecast period from
2006 through 2011. The decrease is due mainly to a decrease in tire production—closing/idling
of tire plants and tire production moving offshore.
China is expected to drive much of the SBR demand and will be the fastest-growing
market during the forecast period. Currently, China is adding and also studying
new SBR production facilities in order to meet its current and future demand.
A sharp increase in production and consumption of SBR in India is also expected
in the near future.
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