Plastics manufacturing, chemicals used 1,3-butadiene

Uses Secondary plasticizer for polyvinyl chloride co-polymers of styrene-butadiene and chlorinated rubber to improve chemical resistance to attack. In fluorescent and high-intensity discharge ballasts manufactured prior to 1979 (U.S. EPA, 1998). 

As of this date, there is no lithium or alkyl-lithium catalyzed polyisoprene manufactured by the leading synthetic rubber producers- in the industrial nations. However, there are several rubber producers who manufacture alkyl-lithium catalyzed synthetic polybutadiene and commercialize it under trade names like "Diene Rubber"(Firestone) "Soleprene"(Phillips Petroleum), "Tufdene"(Ashai KASA Japan). In the early stage of development of alkyl-lithium catalyzed poly-butadiene it was felt that a narrow molecular distribution was needed to give it the excellent wear properties of polybutadiene. However, it was found later that its narrow molecular distribution, coupled with the purity of the rubber, made it the choice rubber to be used in the reinforcement of plastics, such as high impact polystyrene. Till the present time, polybutadiene made by alkyl-lithium catalyst is, for many chemical and technological reasons, still the undisputed rubber in the reinforced plastics applications industries. 

Methacrylonitrile (1) differs from 2 only in that it has a methyl (CH3) group on the a-carbon atom. It too is widely used in the preparation of homopolymers and copolymers, elastomers, and plastics and as a chemical intermediate in the preparation of acids, amides, amines, esters, and other nitriles. In a study conducted by the NTP in which 1 was administered orally to mice for 2 years, there was no evidence that it caused cancer, although other less serious toxic effects were noted [27]. Because 1 does not cause cancer, but undergoes many of the same nucleophilic addition reactions as 2 at the (3-carbon, it is sometimes used as a safer commercial replacement for 2, such as in the manufacture of an acrylonitrile-butadiene-styrene-like polymer that provides improved barrier properties to gases such as carbon dioxide in carbonated beverage containers. 

Acrylonitrile resembles VC, a carcinogen, in structure. It is a flammable, explosive liquid (b.p. 77 C, V.P. 80 mm at 20°C). AN is a component of acrylic and modacrylic fibers produced by copolymerization with other monomers, e.g., with methyl acrylate, Me-methacrylate, vinyl acetate, VC and VDC. Other major uses of AN include copolymerizations with butadiene and styrene to produce ABS polymers, and with styrene to yield SAN resins which are used in the manufacture of plastics. Nitrile elastomers and latexes are also made with AN, as are a number of other chemicals, e.g. acrylamide and adiponitrile. Acrylonitrile is also used as a fumigant. 

Butadiene is used as a chemical intermediate and as a polymer component in the synthetic rubber industry, the latter accounting for 75% of the butadiene produced. Styrene-butadiene rubber, polybutadiene rubber, adiponitrile, styrene-butadiene latex, acrylonitrile-butadiene-styrene resins, and nitrile rubber are used in the manufacture of tires, nylon products, plastic bottles and food wraps, molded rubber goods, latex adhesives, carpet backing and pads, shoe soles, and medical devices. 

Styrene is produced by the alkylation of benzene with ethylene followed by catalytic dehydrogenation. It is used in the manufacture of general-purpose and high-impact polystyrene plastics ( 50%), expanded polystyrene ( 7%), copolymer resins with acrylonitrile and butadiene ( 7%) or acrylonitrile only ( 1%), styrene-butadiene latex ( 6%) and synthetic rubber ( 5%), unsaturated polyester resins ( 6%), and as a chemical intermediate. 

Ethylbenzene is a colorless aromatic liquid. It is only slightly soluble in water, but infinitely soluble in alcohol and ether. Additional properties are listed in Table 1. Ethylbenzene is chemically reactive with the most important reaction being its dehydrogenation to form styrene. Styrene is used to produce polystyrene, which is used in the manufacture of many commonly used products such as toys, household and kitchen appliances, plastic drinking cups, housings for computers and electronics, foam packaging, and insulation. In addition to polystyrene, styrene is used to produce acrylonitrile-butadiene-styrene polymer (ABS), styrene-acrylonitrile polymer (SAN), and styrene-butadiene synthetic rubber (SBR). 

MAJOR USES Manufacture of chemicals including acrylic fiber, plastics, rubber elastomers, plasticizers, solvents, polymeric materials, dyes, pharmaceuticals, insecticides and nylon formation of high impact resins such as styrene acrylonitrile and acrylonitrile butadiene styrene. 

Ammoxidation catalysis is an industrially important process that is used to manufacture high volume chemical intermediates for a wide range of pol3mier products as well as nitrile chemicals and chemical intermediates for agricultural and pharmaceutical use. Ammoxidation processes are used to produce the two most commercially important nitrile chemicals, acrylonitrile (C3H3N) and HCN. The former is used to make acrylic fibers, Nylon (DuPont), and performance polymers including ABS (acrylonitrile-butadiene-styrene). The latter is used in the manufacture of herbicides, plastic sheets, and Nylon. 

The basic petrochemicals, which are produced in the largest volumes, are separated into two classes olefins and aromatics. The olefins include ethylene, propylene, and 1,3-butadiene. The aromatics are benzene and the xylenes. These chemicals are used primarily for the manufacturing of plastics, synthetic rubbers, and fibers. A wide range of other chemicals is also produced in somewhat lesser volumes, but with a variety of applications. This discussion is limited to the major chemicals identified previously. 

Lastly, 4% of the demand for oil goes to make chemical feedstocks for the manufacture of synthetic plastics, elastomers, and many chemicals, some of which are rubbercompounding chemicals. Of course, this 4% is extremely critical to the world economy. In this world economy, the price mechanism is used to determine the allocation of the crude petroleum distribution among its many uses. For example, if the price of the oil used to make styrene and butadiene to copolymerize into SBR (styrene butadiene rubber) becomes too high, there might be some substitution over to natural rubber if it is technically feasible. While the price elasticity of demand for petroleum for use in the rubber industry is rather inelastic, many times it is just as inelastic for use by the transportation sector or the residential markets. 

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