Styrene-acrylonitrile copolymers synthesis

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 outer glassy shell is designed to prevent coalescence of rubbery particles during synthesis and drying, and to insure a good interface with the matrix. The shell is usually based on styrene/acrylonitrile or styrene/methyl methacrylate copolymers. Depending on the acrylonitrile or methyl methacrylate content, the compatibility between the shell and the matrix can be varied over a wide range. 

Choi, Y.S. Xu, M. Chung, I.J. Synthesis of exfoliated poly(styrene-co-acrylonitrile) copolymer/silicate nanocomposite by anulsion pol3miaization monomer composition effect on morphology. Polymer 2003, 44, 6989-6994. 

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]. 

Fawcett, A. H. Foster, A. B. Hania, M. Hohn, M. Mazebedi, J. L. McGaffery, G. O. Mullen, E. Toner, D. Silicone Graft Copolymers with Acrylonitrile, Ghloroprene, Styrene, Methylmethacrylate, and an Olefin. In Synthesis and Properties of Silicones and Silicone-Modified Materials-, Clarson, S. J., Fitzgerald, J. J., Owen, M. J., Smith, S. D., Van Dyke, M. E., Eds. ACS Symposium Series 838 American Chemical Society Washington, DC, 2003 pp 318-328. 

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. 

While free-radical chain reactions were known shortly after the turn of the 20th century, it was not until the mid-1930s that free-radical polymerization was recognized. Today, free-radical polymerization finds application in the synthesis of many important classes of polymers including those based upon methacrylates, styrene, chloroprene, acrylonitrile, ethylene, and the many copolymers of these vinyl monomers. Many good reviews and books on this subject are available.12... 

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. 

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 ... 

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 prefix g describes graft copolymers and the prefix b describes block copolymers. In this system of nomenclature, the first polymer segment corresponds to the homopolymer or copolymer that was formed during the first stage of the synthesis. Should this be a graft copolymer then this will represent the backbone polymer. For instance, if polystyrene is graft copolymerized with polyethylene, the product is called poly(ethylene-g-styrene). A more complex example can be poly (butadiene-co-styrene-g-acrylonitrile-co-vinylidine chloride). Similarly, examples of block copolymers would be poly(acrylonitrile- -methyl methacrylate) or poly(methyl methacry late- -acry lonitrile). 

ATRP was recently reported as a new and powerful route to the synthesis of well-defined (co)polymers of such monomers as styrene, acrylates, methyl methacrylate, acrylonitrile, and isobutene. ATRP is a versatile tool for preparation of random, block, alternating, and gradient copolymers with controlled molecular weight, narrow polydispersities, and desired architectures. 

Pittmann et al. also reported in 1973 the synthesis of copolymers of tricarbonyl(r/ -vinylcyclopentadienyl)-manganese with styrene, methyl acrylate, acrylonitrile, vinyl acetate or vinylferrocene (8) and their conductivity [12]. All the polymers are insulators in the neutral state (4 X 10 to 1 x 10 Scm ) but their conductivity increases up to 9 x 10 S cm on exposure to high humidity for 3 days. It was not shown whether proton conduction or electronic conduction was dominant in these conditions. 

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