Styrene and acrylonitrile

Explosions due to the presence of peroxides formed by aerial oxidation of ethers and tetrahydrofuran, decahydronaphthalene, acrylonitrile, styrene and related compounds. 

Anionic polymerization is better for vinyl monomers with electron withdrawing groups that stabilize the intermediates. Typical monomers best polymerized by anionic initiators include acrylonitrile, styrene, and butadiene. As with cationic polymerization, a counter ion is present with the propagating chain. The propagation and the termination steps are similar to cationic polymerization. 

Kochi (1956a, 1956b) and Dickerman et al. (1958, 1959) studied the kinetics of the Meerwein reaction of arenediazonium salts with acrylonitrile, styrene, and other alkenes, based on initial studies on the Sandmeyer reaction. The reactions were found to be first-order in diazonium ion and in cuprous ion. The relative rates of the addition to four alkenes (acrylonitrile, styrene, methyl acrylate, and methyl methacrylate) vary by a factor of only 1.55 (Dickerman et al., 1959). This result indicates that the aryl radical has a low selectivity. The kinetic data are consistent with the mechanism of Schemes 10-52 to 10-56, 10-58 and 10-59. This mechanism was strongly corroborated by Galli s work on the Sandmeyer reaction more than twenty years later (1981-89). 

Table 15. Apparent molecular weights (M ) by LS in different solvents for terpolymers comprising acrylonitrile, styrene and methyl methacrylate...

Many petrochemicals have been harnessed because they have two common characteristics they re simple and they re reactive. Acrylic add (AA) is the simplest organic acid that contains a double bond. Its that vinyl group again, CH2=CH-, the same one found in acrylonitrile, styrene, and vinyl chloride. Because it s an acid and because it has the double bond, it s highly reactive. It readily undergoes polymerization (reacts with itself because of the double bond) and esterification (reacts with alcohol because its an acid). 

In experiments with a supported palladium catalyst, Pd/C, satisfactory yields were obtained without the use of phosphine ligands for the Heck reactions of aryl iodide with acrylonitrile, styrene, and methyl methacrylate in the ionic liquid [BMIM]PF6 (259). The addition of triethylamine improved the yields. The Pd/C remained in the ionic liquid only. The ionic liquid containing Pd/C can be reused as... 

Calculate the composition of the initial terpolymer that would be produced from the radical polymerization of a solution containing acrylonitrile, styrene, and 1,3-butadiene in mole fractions of 0.47, 0.47, and 0.06, respectively. 

If no suitable reagent is present, the nitrile oxide immediately dimerizes into furoxane. Such reagents can be activated olefins such as vinyl esters and ethers, acrylonitrile, styrene and cycloolefins. 

Copolymers of acrylonitrile and methyl acrylate and terpolymers of acrylonitrile, styrene, and methyl methacrylate are used as bamer polymers. Acrylonitrile copolymers and multipolymers containing butyl acrylate, ethyl aciylate, 2-ethylhexyl acrylate, hydroxyethyl acrylate, methyl methaciylate. vinyl acetate, vinyl ethers, and vinylidene chlonde are also used in bamer films, laminates, and coatings. Environmentally degradable polymers useful in packaging are prepared from polymerization of acrylonitrile with styrene and methyl vinyl ketone. 

Recently, Akashi and coworkers [153, 154] synthesized novel spherical particles on which nano-projections are uniformly distributed over the whole surface like confetti by the one-step dispersion terpolymerization of acrylonitrile, styrene, and the PEO macromonomer 9a in ethanol/water media. The control of nanoparticle morphology by a one-step synthetic procedure is important to self-organization at the polymer chain level, which is a basis for the formation of biological nanoconstructs such as viruses and organelles. 

Phenyl phenacyl sulphide has also been reported to be a good photoinitiator for the polymerization of methyl methacrylate, acrylonitrile, styrene, and vinyl acetate (30). 

Acrylonitrile, styrene, and isobutylene were irradiated at low temperatures in binary mixtures with either low molecular weight compounds or polymers. The reagents were mixed at room temperature, sealed under vacuum, and the resulting liquid or swollen polymer was rapidly cooled to the irradiation temperature. Irradiations were carried out with cobalt-60 gamma-rays at a dose rate of 2000 rads/min. After irradiation the samples were warmed to room temperature under two different standard conditions. The sealed ampoules were either immersed in a water bath at 25 °C. immediately after irradiation or first opened at —196°C. and then stirred in a large excess of warm acetone. The polymer was separated and dried to constant weight. 

What appears to be conclusive evidence for the participation of free radicals in some hydrogen peroxide systems is contained in the work of Baxendale, Evans, and Park (45). They discovered that monomers such as acrylonitrile, styrene, and methyl methacrylate are rapidly polymerized if they are present when hydrogen peroxide is reduced by ferrous,... 

Unstable compounds such as peroxides and hydroperoxides are usual initiators for vinyl polymerization reactions. These groups can be introduced into a solid polymer by pre-irradiation in the presence of air or oxygen. Thermal decomposition of these groups in the presence of monomer yields graft copolymers. Some examples include grafting of acrylonitrile, styrene, and methyl methacrylate to polyethylene and polypropylene. 

Methyl methacrylate has been copolymerized with a wide variety of other monomers, such as acrylates, acrylonitrile, styrene, and butadiene. Copolymerization with styrene gives a material with improved melt-flow characteristics. Copolymerization with either butadiene or acrylonitrile, or blending PMMA with SBR, improves impact resistance. Butadiene-methyl methacrylate copolymer has been used in paper and board finishes. 

The arene substrates are not limited to simple benzene derivatives. A variety of het-eroarenes can also participate in alkene arylations to generate the desired coupling products. Stoichiometric oxidative coupling of aromatic heterocycles such as furan, thiophene, selenophene, A-methylpyrrole, benzofiiran and benzothiophene with a variety of alkenes, including acrylonitrile, styrene and methyl acrylate, have been extensively studied by Fu-jiwara and coworkers [8]. Furan, thiophene, selenophene and A-methylpyrrole are easily alkenylated with alkenes to give 2-alkenylated and 2,5-dialkenylated heterocycles in relatively low yields (3 6%) [8a], while the reactions of benzofuran and benzothiophene with alkenes produced a mixture of 2- and 3-alkenylated products [8b]. 

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