Abstract Acrylonitrile Research Articles

Copolymers of Acrylonitrile with Some Brominated Acrylates

Abstract Acrylonitrile was copolymerized with 2,3-dibromopropyl acrylate, 2,4,6-tribromophenyl acrylate, or pentabromophenyl acrylate in either aqueous emulsion or dimethylformamide solutions with azobisisobutyronitrile as the free radical initiator. The thermal properties and the flammability characteristics of the resulting polymers were also investigated. The reactivity ratios of the monomers and the initial reaction rates for homopolymerization and copolymerization reactions in dimethylformamide were determined. The monomer reactivity ratios were found to depend slightly on the reaction medium; the reaction rates for both homo-polymerizations and copolymerizations increased in the order pentabromophenyl acrylate > 2,4,6-tribromophenyl acrylate > 2,3-dibromopropyl acrylate > acrylonitrile. Thermal stability measurements (determined from TGA and DTG) showed that poly(2,4,6-tribromophenyl acrylate) and its acrylonitrile copolymers were the most stable polymers and the copolymers of 2,3-dibromopropyl, acr...

Copolymerization of Acrylonitrile with [(2-Methacryloyloxy)alkoxy]trimethylsilanes

Abstract Acrylonitrile (AN) was copolymerized with [(2-methacryloyloxy)-ethoxy] trimethylsilane (2-MAETMS) and [(2-methacryloyloxy)-propoxy] trimethylsilane (2-MAPTMS) in dimethylformamide (DMF) and dimethylsulfoxide (DMSO) between 50 and 70°C using azobisisobutyronitrile (AIBN) as initiator. The copolymer composition was determined by silicon estimation, and the reactivity ratios were calculated by the Kelen-Tiidbs method. Li both systems, r1 (AN) and r2(2-MAETMS/2-MAPTMS) are higher in DMF compared to the values in DMSO. Arrhenius parameters were derived for the AN-2-MAETMS system. The difference between the activation energies (E11-E12) favors self-propagation for the acrylonitrile radical, whereas A11/A12 favors cross-propagation. In the case of the 2-MAETMS radical, E22 - E21 favors cross-propagation but A22/A21 favors self-propagation. The influence of the comonomers on some of the basic properties of copolymers (e.g., intrinsic viscosity and glass transition temperature) have also been studied.

Acrylonitrile adsorption over copper catalysts

Acrylonitrile adsorption over Cu−Pd catalysts decreases the CN-bond order. The addition of palladium enhances acrylonitrile adsorption and promotes the stabilization of copper in the zerovalent state. Strongly bound forms of adsorbed water molecules are not likely to be involved in acrylonitrile hydration.

Vibrational spectroscopy at high pressures. Part 41.—Infrared spectra of acrylonitrile and polyacrylonitrile

Acrylonitrile has been examined visually and by i.r. spectroscopy to 50 kbar. The liquid freezes at ca. 11 kbar. There is a phase transformation in the solid near 27 kbar. Above 10 kbar polyacrylonitrile co-exists with the liquid or solid phases: this polymer has an i.r. spectrum closely similar to that from the product of u.v.-induced polymerisation under ambient conditions.

Selective hydrogenation of acrylonitrile over a supported Ni catalyst

Acrylonitrile can be selectively hydrogenated into propionitrile at about 400 K over a ceramic-supported Ni catalyst. At low surface coverages, the observed rates of hydrogenation are proportional to the first powers of the partial pressures of both acrylonitrile and dihydrogen, in agreement with Langmuir-Hinshelwood kinetics.

Effect of acrylonitrile on trehalase, phosphorylase and acetylcholinesterase activities in Tribolium castaneum Herbst and Trogoderma granarium Everts.

Acrylonitrile inhibited trehalase and phosphorylases in larvae and adults of Tribolium castaneum. In Trogoderma granarium larvae phosphorylases alone were inhibited. Acetylcholinesterase was not affected.

Control of Insects with Fumigants at Low Temperatures: Toxicity of Mixtures of Methyl Bromide and Acrylonitrile to Three Species of Insects1

Acrylonitrile can be mixed with methyl bromide to increase toxicity so that the quantity of methyl bromide required for control of Sitophillus granarius (L.), Tenebrio molitor L., and Tribolium confusum Jacquelin duval is reduced by one half. Mixtures of methyl bromide and acrylonitrile are considerably more effective at low temperatures than methyl bromide alone.

New Catalyst System, FeCI3-Et3-nAICIn (n=1, 2), for the Alternating Copolymerization of Butadiene-1,3 with Acrylonitrile

Abstract Butadiene-1, 3 and acrylonitrile were copolymerized by alkylaluminum halides and ferric chloride systems. The efficiency of the aluminum components of these systems appears to decrease in the following order: Et2AlCl < EtAlCl2 < Et3Al. Effective catalysts were not necessarily dependent on the mixing orders of the catalyst and monomers. It was found that different feed ratios between two monomers, which were varied over a wide range, always resulted in the formation of 1:1 copolymer. In order to investigate the initiation and propagation reactions, electron paramagnetic resonance was measured and a polarographic method was used on the reduction reaction of ferric chloride with organoaluminum halides in acetonitrile.

Grafting of acrylonitrile onto cellulose initiated by ceric ion

AbstractAcrylonitrile was grafted onto cellulose with the use of ceric salt as initiator and the grafting was found to be maximum at 0.6N acid concentration. The effect of monomer and initiator concentration on the extent of grafting was studied. A new method for quantitative estimation of extent of grafting on cellulose was developed and its validity was established. The grafted samples with 20% increase in weight were found to be highly resistant to microorganisms.

POLYMERIZATION OF VINYL MONOMERS IN THE PRESENCE OF CELLULOSE ACETATE

Acrylonitrile (AN), methyl methacrylate (MMA) and vinyl acetate (VAc) were polymerized in the presence of cellulose acetate.In this study, benzoyl peroxide (BPO) was used as an initiator for radical polymerization.The cellulose acetate was treated with vinyl monomers at room temperature or 60°C.The viscosity of the dilute acetone solution of the products was measured, and the thermal stability of the cellulose acetate fiber treated with MMA was also measured.The results obtained are as follows:1) AN and VAc do not polymerize so much as MMA.2) In the case of AN and MMA, Huggins' constant k′ of the dilute acetone solution of the products decrease in comparison with untreated cellulose acetate. However, in the case of VAc, k′ increases a little.3) The cellulose acetate fiber treated with MMA has smaller thermal deformation than that of untreated cellulose acetate fiber.

Infrared Spectra of Polyacrylonitrile Polymerized by Gamma-irradiation at Low Temperatures

Acrylonitrile was polymerized in bulk and in various solutions by gamma irradiation at low temperatures, and the effects of polymerization conditions on the infrared spectruun of polyacrylonitrile were studled. The intensities of absorption bands at 1675 and 2030 cm/sup -1/ were found to vary according to the solvent species and the irradiation temperatures. (P.C.H.)

Vapor Phase Method for Preparation of Polyacrylonitrile Coated Cotton Yarn and Physical Properties of the Product

Acrylonitrile vapors were polymerized within and upon the individual fiber surfaces of scoured cotton yarns to yield coated products having new and interesting properties. The uniformity of the polyacrylonitrile coating is shown in electron micrographs of the fiber surfaces. Breaking strengths were increased appreciably, particularly when the process was applied to prestretched yarns. High frictional characteristics were ex hibited when one coated yarn was pulled against another. Excellent resistance to rot and flat abrasion was obtained in conjunction with a relatively minor improvement in resistance to acid degradation. No essential change in heat and weather resistance was noted. Resistance to flexing, however, was adversely affected by the presence of the polyacrylonitrile. These polymer coated yarns can be prepared with essentially the same equipment and procedures as required for the vapor phase cyanoethylation of cotton ; the only exception is that a different catalyst is employed. This illustrates the utility of acrylonitrile for preparation of a variety of useful cotton products,

A SYNTHESIS OF PHENYLALANINE AND TYROSINE

Acrylonitrile and diazonium chlorides are condensed to give α-chloro-β-arylpropionitriles which can be converted to α-amino acids. Phenylalanine is obtained by transforming α-chloro-β-phenylpropionitrile into the amide with sulphuric acid, hydrolysing to the acid with hydrochloric acid and animating with ammonia and ammonium carbonate. Tyrosine is obtained from α-chloro-β-p-methoxyphenylpropionitrile by direct hydrolysis with mixed acetic and hydrochloric acids and ammonolysis with ammonia and ammonium carbonate.