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solid or viscous liquid, depending upon the degree of polymerisation

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Molded or extruded into toys, packaging, appliances, communication cassettes, dinnerware and serviceware.

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SBR is prepared mainly by emulsion and solution polymerization in a free-radical process with a mercaptan, such as dodecylmercaptan, which is used as a chain-transfer agent to control molecular weight. In the emulsion process, a soapstabilized water emulsion of styrene and butadiene is polymerized in continuous reactors to form SBR elastomer. “Cold” SBR is produced at a temperature of 5–10°C, and “hot” SBR at about 50°C . Solution SBR is typically made in hydrocarbon solution with an n-butyllithium initiator. The major differences between emulsion and solution styrene–butadiene are in the linearity and molecular-weight distribution of the polymer chains. In nonpolar solvents, the tendency is to produce block copolymer, but random copolymers are formed in polar solvents. SBR can be vulcanized similar to natural rubber but generally requires less sulfur and is more accelerated because of its lowunsaturation.

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Questionable carcinogen.

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Styrene Butadiene Rubber is prepared in large quantities for tire treads and other, similar uses. The properties, molecular weight, and percentage of monomer can all be controlled in the polymerization process. Hazards of the SBR industry have been identified and related mostly to the monomers and additives. Contact dermatitis and leukemia have been associated with solvent and additive use but not with the actual polymer itself (Checkoway et al., 1984; Kilpikari, 1982). Epidemiological studies in the industry have not revealed a significant increase in disease or causes of death (Matanoski and Schwartz, 1987; Meinhardt et al., 1982). The hazards of the butadiene and styrene monomers were discussed previously.

Safety Profile

An eye irritant. Questionable carcinogen. When heated to decomposition it emits acrid smoke and irritating fumes. See also POLYMERS, INSOLUBLE.

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Henan Fengda Chemical Co., Ltd	+86-371-86557731 +86-13613820652	info@fdachem.com	China	20288	58
airuikechemical co., ltd.	+undefined86-15315557071	sales02@sdzhonghuimaterial.com	China	983	58
Hebei Zhuanglai Chemical Trading Co.,Ltd	+8613343047651	admin@zlchemi.com	China	3002	58
Henan Tianfu Chemical Co.,Ltd.	+86-0371-55170693 +86-19937530512	info@tianfuchem.com	China	21639	55
career henan chemical co	+86-0371-86658258 +8613203830695	sales@coreychem.com	China	29886	58
Hubei Jusheng Technology Co.,Ltd.	18871490254	linda@hubeijusheng.com	CHINA	28172	58
Hubei xin bonus chemical co. LTD	86-13657291602	linda@hubeijusheng.com	CHINA	22963	58
Shandong chuangyingchemical Co., Ltd.	18853181302	sale@chuangyingchem.com	CHINA	5906	58
Chongqing Chemdad Co., Ltd	+86-023-6139-8061 +86-86-13650506873	sales@chemdad.com	China	39894	58
Shaanxi Dideu Medichem Co. Ltd	18192627656	1012@dideu.com	China	3002	58

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