Styrene-butadiene rubber usage

There are two classes of polyolefin blends elastomeric polyolefin blends also called polyolefin elastomers (POE) and nonelastomeric polyolefin blends. Elastomeric polyolefin blends are a subclass of thermoplastic elastomers (TPEs). In general, TPEs are rubbery materials that are processable as thermoplastics but exhibit properties similar to those of vulcanized rubbers at usage temperatures (19). In TPEs, the rubbery components may constitute the major phase. However, TPEs include many other base resins, which are not polyolefins, such as polyurethanes, copolyamides, copolyesters, styrenics, and so on. TPEs are now the third largest synthetic elastomer in total volume produced worldwide after styrene-butadiene rubber (SBR) and butadiene mbber (BR). 

World rubber usage of around 25.8 million metric tons is split between natural rubber, which constitutes about 43% of global consumption, and synthetic rubber, of which styrene-butadiene rubber (SBR) accounts for 21%. The balance of synthetic rubbers (36%) consists of polybutadiene rubber (BR) and a range of specialty polymers such as polyurethanes, halogenated polymers, silicones, and acrylates. Traditionally, the growth of synthetic and natural rubber consumption is virtually in line with the change in gross domestic product of, collectively. North America, Europe, Japan, China, and India. 

Chewing gum is enjoying increased usage in the world and would be in short supply if chicle were the only base. Other bases now being used include refined pine tree resins from the southeastern U.S., jelutong from Indonesia and Malaysia, and synthetic rubbers such as polyisobutylene and styrene-butadiene rubber. Chicle consumption is estimated in the United States at 1000- 2000 tons per year. 

Water-base adhesives are made of materials that can be dissolved or dispersed in water. Both natural (cellulosic, dextrin, starch) and synthetic (phenol formaldehyde, polyvinyl acetate, styrene-butadiene rubber, nitrile rubber) polymer materials are used in manufacturing water-base adhesives. Their primary application is in packaging, with a much smaller percentage usage in construction. Their share of the market, however, has been increasing due to health concerns associated with some of the solvents used in organic-solvent adhesives. 

The serious development of synthetic rubbers commenced in the late 1930s and early 194(ls. accelerated by a cutoff of supplies of natural rubber because of political turmoil and war. Synlhetic rubbers fall into two major classifications (1) general-purpose rubbers, the major volume of which is nevertheless used for tire production and (2) specialty rubbers that essentially find little use in (ires, hut that are important for a number of other categories. Synthetic rubbers have not replaced natural rubber for numerous uses. For large, heavy-duty truck and bus tires, natural rubber tends to mn considerably cooler and wears better than a blend of natural and synthetic rubbers. On the other hand, a tire (read made of a blend of styrene-butadiene (SBR) and butadiene rubber (polybutadiene) wears longer than natural rubber in conventional automobile, usage, where lower temperatures can be maintained. 

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