Styrene-acrylonitrile, synthesis using

Styrene is at the centre of an important industry, with a value of some 66 billion euros. The styrene production capacity is ca. 20 Mt/a worldwide. Most is obtained by ethylbenzene dehydrogenation and all the production is used for the synthesis of polymers (polystyrene, styrene-acrylonitrile, styrene-butadiene) used as plastics and rubbers in the manufacture of household products packaging, tubes, tires, and endless other applications (see also Chapter 7). 

Uses Copolymerized with methyl acrylate, methyl methacrylate, vinyl acetate, vinyl chloride, or 1,1-dichloroethylene to produce acrylic and modacrylic fibers and high-strength fibers ABS (acrylonitrile-butadiene-styrene) and acrylonitrile-styrene copolymers nitrile rubber cyano-ethylation of cotton synthetic soil block (acrylonitrile polymerized in wood pulp) manufacture of adhesives organic synthesis grain fumigant pesticide monomer for a semi-conductive polymer that can be used similar to inorganic oxide catalysts in dehydrogenation of tert-butyl alcohol to isobutylene and water pharmaceuticals antioxidants dyes and surfactants. 

Acrylonitrile is currently the second largest outlet for propylene (after polypropylene). It is used as a monomer for synthetic fibers and acrylic plastics (thermoplastics and food packaging mainly), AS (acrylonitrile-styrene) resins, and ABS (aerylonitrile-butadiene-styrene) thermoplastics, as well as in the synthesis of acrylamide, adiponitrile, and nitrile elastomers. The manufacture of acrylonitrile is exclusively based on the one-step propylene ammoxidation process. Originally developed by Sohio, Standard Oil Company (now part of BP America), the conventional method used since 1957 employs a fluidized-bed reactor and multicomponent catalysts based on Mo-containing mixed-metal oxides. Over the years, the industrial... 

When the polymer was prepared by the suspension polymerization technique, the product was crosslinked beads of unusually uniform size (see Fig. 16 for SEM picture of the beads) with hydrophobic surface characteristics. This shows that cardanyl acrylate/methacry-late can be used as comonomers-cum-cross-linking agents in vinyl polymerizations. This further gives rise to more opportunities to prepare polymer supports for synthesis particularly for experiments in solid-state peptide synthesis. Polymer supports based on activated acrylates have recently been reported to be useful in supported organic reactions, metal ion separation, etc. [198,199]. Copolymers are expected to give better performance and, hence, coplymers of CA and CM A with methyl methacrylate (MMA), styrene (St), and acrylonitrile (AN) were prepared and characterized [196,197]. 

Boronic acids (69 and 70) (Fig. 45) with more than one boronic acid functionality are known to form a polymer system on thermolysis through the elimination of water.93 Specifically, they form a boroxine (a boron ring system) glass that could lead to high char formation on burning. Tour and co-workers have reported the synthesis of several aromatic boronic acids and the preparation of their blends with acrylonitrile-butadiene-styrene (ABS) and polycarbonate (PC) resins. When the materials were tested for bum resistance using the UL-94 flame test, the bum times for the ABS samples were found to exceed 5 minutes, thereby showing unusual resistance to consumption by fire.94... 

Copolymerization allows the synthesis of an almost unlimited number of different products by variations in the nature and relative amounts of the two monomer units in the copolymer product. A prime example of the versatility of the copolymerization process is the case of polystyrene. More than 11 billion pounds per year of polystyrene products are produced annually in the United States. Only about one-third of the total is styrene homopolymer. Polystyrene is a brittle plastic with low impact strength and low solvent resistance (Sec. 3-14b). Copolymerization as well as blending greatly increase the usefulness of polystyrene. Styrene copolymers and blends of copolymers are useful not only as plastics but also as elastomers. Thus copolymerization of styrene with acrylonitrile leads to increased impact and solvent resistance, while copolymerization with 1,3-butadiene leads to elastomeric properties. Combinations of styrene, acrylonitrile, and 1,3-butadiene improve all three properties simultaneously. This and other technological applications of copolymerization are discussed further in Sec. 6-8. 

The primary use of TBBPA is as a flame retardant in epoxy resin circuit boards and in electronic enclosures made of polycarbonate-acrylonitrile-butadiene-styrene (PC-ABS). Other applications of TBBPA include its use as a flame retardant for plastics, paper, and textiles as a plasticizer in adhesives and coatings and as a chemical intermediate for the synthesis of other flame retardants (e.g., TBBPA allyl ether). It is also been applied to carpeting and office furniture as a flame retardant. 

A series of enantioselective imprinted polymer membranes for amino acid and peptide derivatives were prepared using oligopeptides as functional monomers [42-45]. A tetrahydrofuran solution containing a template molecule, a functional monomer of a peptide derivative attached on polystyrene resin that is commonly used in solid-phase peptide synthesis, copolymer of acrylonitrile and styrene, was poured into a flat laboratory dish and left for 24 h to remove the solvent. 

The tosylation of carbon can be accomplished using electron transfer conditions. Treatment of styrene and analogs with Copper(II) Chloride and tosyl chloride or Benzenesulfonyl Chloride results in a formal replacement of the vinyl proton by the sulfonyl moiety (eq 35). The intermediacy of a trans-(S-chloro sulfone has been demonstrated by H NMR. Treatment with base induced the elimination of HCl. A variety of other sulfonyl transfer reagents can be ertployed in the synthesis of isolated /3-chloro sulfones, with good results (60-97% yield) for a variety of alkenes (ethylene, 1-butene, 2-butene, 1-octene, acrylonitrile, methyl acrylate, and 1,3-butadiene). ... 

Copolymerization of 18 with styrene and acrylonitrile In the range of 40 to 60 mol % of the metallomonomer the copolymer composition does not depend on the monomeric mixture. The copolymers are soluble in benzene the molecular weights are about 10 Da. Under copolymerization conditions (75 °C, benzene, 1% of the initiator) of 18 with acrylonitrile (25 mol %) a light-yellow product containing -12% vanadium was obtained. The yield was 15%, the product is soluble in DMFA and DMSO, and its intrinsic viscosity was 0.11 (DMSO, 30 °C). IR 1720 (vc=o), 2245 cm (vc n) the ratio of the intensities of the absorptions /(C=0)//(C=N) = 13 1. This method can also be used for the synthesis and polymerization of optically active metallomonomers. 

The direct introduction of peroxide groups into the backbone of polymers, such as poly(methyl methacrylate), has been used to produce macro-molecular initiators for the synthesis of block copolymers for example, poly(methyl methacrylate- -acrylonitrile) and poly(methyl methacrylate-Z -styrene). Ozonization can also be used, with careful control of the degree of ozonolysis, to introduce epoxy ring structures into natural rubber ... 

Uses Plasticizer, emulsifier, and coalescent for acrylic latexes, styrene-acrylic floor polishes solvent for polymers, insecticides, veterinary medicine selective solvent (acet ene, acrylonitrile prod.) process solvent (phamraceuticals) specialty inks monomer for nylon-4 pharmaceutical solubilizer, intermediate synthesis of piracetam treatment of cerebral distress... 

D- or L-amino acids were attached to polystyrene beads using standard Merrifield solid phase pepetide synthesis. These modified beads were subsequently mixed with a solution of a copolymer of styrene and acrylonitrile and the print molecule before casting as a thin film [62-66] (Fig. 18). Polystyrene beads were modified with the tetra peptide H-Asp(OcHex) -Ile-As (OcHex) -Glu(OBz) -CH2- (DIDE-resin), H-Glu(OBz) -Glu(OBz) -Glu(OBz) -(EEE resin), and H-Glu(OBz) -Phe-Phe (EFF resin, Fig. 19). 

The other important diol which finds wide application in synthesis of flame retardant epoxy thermosets is 4,4 -isopropylidene bis(2,6-dibromo-phenol) (tetrabromobisphenol-A,TBPA).The primary use of TBPA is as a reactive flame retardant in epoxy resin-based circuit boards and in electronic enclosures made of polycarbonate-acrylonitrile, butadiene-styrene, etc. Hexafluorobisphenol-A (bisphenol-AF, hexafluoroisopropylidene diphenol) has also been used for the synthesis of fluorinated epoxy resin aiming at the anticorrosion coatings market for industrial vessels and pipes. The key disadvantages of fluorinated epoxies are their relatively high costs and low Tg, which limit their commercialisation. Thus utilisation of such diols in vegetable oil-based epoxy resins may result in similar performance. 

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