Photopolymerization Of Acrylonitrile Research Articles

Vibrational overtone initiated photopolymerization of acrylonitrile

Vibrational overtone activated polymerization of acrylonitrile (AN) has been demonstrated using two initiators, benzoyl peroxide (BP), and 2,2′-(azobis)isobutyronitrile (AIBN). Excitation of the fifth vibrational overtone of the CH stretch of AIBN at 627 nm and BP at 604 nm initiates the reaction. Monomer conversions were monitored by a gravimetric method. In both cases, the wavelength selectivity was investigated by irradiating the monomer/initiator mixtures at the absorption maximum of the initiator, the absorption maximum of the monomer, and at a wavelength (580 nm for AN/AIBN and 625 nm for AN/BP) where neither the initiator nor the monomer absorbs light. For the AN/AIBN mixture, after 48 h the monomer conversion for the irradiation on the peak absorption of AIBN (627 nm) is about twice as large as the irradiation at 580 nm. For the AN/BP mixture, after 48 h the monomer conversion for the irradiation on the peak absorption of BP (604 nm) is about a factor of 2.2 larger than for the irradiation at 625 nm. The overall quantum yields of both polymerizations were estimated. After 48 h the overall quantum yield for the AN/AIBN mixture irradiated at the initiator absorption (Φ627 = 21083) is about 10 times larger than for the sample irradiated at the pure monomer absorption (Φ595 = 1942). For the AN/BP mixture, the 604 nm quantum yield (Φ604 = 1096) is about 2.4 times larger than the 595 nm quantum yield (Φ595 = 448). The influence of the initiator concentration is also presented. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 565–571, 2003

Photopolymerization of acrylonitrile in concentrated aqueous zinc halide solutions

Crosslinked polyacrylonitrile (PAN) was obtained with a high yield from the photoinduced polymerization of acrylonitrile (AN) in concentrated aqueous zinc chloride solution. It was found that the presence of zinc chloride results in the promotion of the radical generation in the photoinitiation process as well as an increase in the rate of propagation. Any attempt to isolate the polymer from the reaction mixture was not successful due to the insolubility of the polymer to any conventional solvents to polyacrylonitrile (PAN); therefore, the reaction mixtures, consisting of PAN, zinc chloride, and water—which are referred to as the polymer hybrid system—was used without further purification. The effect of other zinc halides on the polymerization such as zinc bromide and zinc iodide was also investigated in connection with the photoinitiation mechanism, which reveals that the complex (Zn++(AN)x(OH−)yCl) is the species that is responsible for the photoinitiation. It was found that the transparent, stretchable polymer hybrid systems are electric conductive and turn to black upon heating to 160°C due to the conversion of the nitrile group of PAN to tetrahydronaphthyridine rings. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2588–2594, 2000

Vinyl monomers bearing chromophore moieties and their polymers. IV. Fluorescence and photosensitizing behavior of 8-acryloyloxyquinoline and its polymer

Acrylic monomers bearing electron-donating quinolyl moiety, i.e., 8-acryloyloxyquinoline (AQ) was prepared and polymerized. It was found that the fluorescence intensity of AQ was much lower than that of P(AQ) at the same chromophore concentration. The fluorescence of P(AQ) could be quenched by electron-deficient vinyl monomers, such as acrylonitrile (AN) and methyl methacrylate (MMA). This is another example of the “fluorescence structural self-quenching effect” termed by us previously, and demonstrates again that this phenomenon is not an accidental but a general one for acrylic monomers bearing electron-donating chromophores. The photopolymerization of acrylonitrile (AN) sensitized by AQ and P(AQ) as well as combining with carbon tetrabromide (CBr4) was studied kinetically. From the rates of the polymerization (Rp) and overall activation energies obtained for these four systems, it was found that Rp sensitized by the binary systems was much higher than by AQ or P(AQ) alone, while the molecular weights of the resulting P(AN) were lower. The fluorescent analysis of the resulting P(AN) in solution showed that the sensitizers also entered into the P(AN) chains. A mechanism of charge transfer complex (CTC) formation was tentatively suggested for the photopolymerization of AN initiated by these four systems. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1087–1093, 1997

Vinyl monomers bearing chromophore moieties and their polymers. IV. Fluorescence and photosensitizing behavior of 8‐acryloyloxyquinoline and its polymer

Acrylic monomers bearing electron-donating quinolyl moiety, i.e., 8-acryloyloxyquinoline (AQ) was prepared and polymerized. It was found that the fluorescence intensity of AQ was much lower than that of P(AQ) at the same chromophore concentration. The fluorescence of P(AQ) could be quenched by electron-deficient vinyl monomers, such as acrylonitrile (AN) and methyl methacrylate (MMA). This is another example of the “fluorescence structural self-quenching effect” termed by us previously, and demonstrates again that this phenomenon is not an accidental but a general one for acrylic monomers bearing electron-donating chromophores. The photopolymerization of acrylonitrile (AN) sensitized by AQ and P(AQ) as well as combining with carbon tetrabromide (CBr4) was studied kinetically. From the rates of the polymerization (Rp) and overall activation energies obtained for these four systems, it was found that Rp sensitized by the binary systems was much higher than by AQ or P(AQ) alone, while the molecular weights of the resulting P(AN) were lower. The fluorescent analysis of the resulting P(AN) in solution showed that the sensitizers also entered into the P(AN) chains. A mechanism of charge transfer complex (CTC) formation was tentatively suggested for the photopolymerization of AN initiated by these four systems. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1087–1093, 1997

Synthesis and photochemical behavior of 2-(N-acridonyl)ethyl methacrylate and its polymer

A polymerizable photosensitizer, 2-(N-acridonyl)ethyl methacrylate (AEMA), containing both aromatic ketone and aromatic tertiary amine moieties in the same molecule, was prepared by reaction of N-hydroxyethyl acridone (HEA) and methacryloyl chloride in the presence of triethylamine (TEA). HEA was obtained by reaction of acridone with ethylene carbonate. The photochemical behavior including photoinitiation and fluorescence properties of AEMA and its polymer P(AEMA) were studied. It was found that the photoinitiation efficiency of monomeric AEMA is lower than that of its polymer for the photopolymerization of acrylonitrile (AN) in DMF. By the kinetic study and the analysis of recorded electron spin resonance spectra of the photoinitiation systems of AEMA or AEMA-dimethylaminoethyl methacrylate (DMAEMA) trapped by 2-methyl-2-nitritopropane (MNP), the mechanism is deduced to be similar to that of the benzophenone-TEA system. The recorded fluorescence spectra show that AEMA and P(AEMA) possess a strong fluorescence emission peak at 410 and 439 nm, respectively. The concentration self-quenching effect was observed with maximum intensities at a concentration of 8.6 X 10 -5 mol/L in DMF for both AEMA and P(AEMA). Even though AEMA has a tertiary amino group and an electron-deficient acrylic double bond in the same molecule, it did not display structural self-quenching effect as we reported previously. This may be due to the two benzene rings in acridone that lessen the electron-donating ability of the N atom. The fluorescence quenching of AEMA and P(AEMA) by electron-donating and electron-accepting compounds was also investigated.

A polymerizable photoredox initiation system for vinyl photopolymerization

AbstractA polymerizable photoredox system consisting of 4‐methacryl oxbenzophenone (MABP) and N,N‐dimethlaminoethyl methacrylate (DMAEMA) used for the photopolymerization of acrylonitrile (AN) was studied. It was found that the polymerization rate is proportional to the 0.93th power for the AN concentration, the 0.28th power for the MABP concentration, and the 0.25th power for the DMAEMA concentration. The overall activation energy of the polymerization obtained is 30.43 kJ/mol. The recorded ESR spectrum indicates that the excited‐state MABP abstraets hydrogen mainly from the methyl group of the dimethylamino moiety. The comparison of the initiation ability of polymeric MABP or polymeric DMAEMA with their monomeric forms has also been done and the results indicate that in good solvents P (MABP) has a much higher initiation ability than that of monomeric MABP, but monomeric DMAEMA and P (DMAEMA) display almost the same initiation ability. In poor solvent, the initiation ability of P (MABP) is not so obviously higher than that in good solvents. The result of UV analysis of P (AN) initiated by the MABP–DMAEMA system indicates that both MABP and DMAEMA not only initiate the photopolymerization of AN, but also enter into P (AN) polymer chains. © 1994 John Wiley & Sons, Inc.

Note Dye-Sensitized Photopolymerization of Acrylonitrile with the Eosin-Periodate Initiating System

Abstract A new photoinitiating system (eosin‐periodate) was employed for the polymerization of acrylonitrile in which dye acts as both sensitizer and reducing agent. The rate of polymerization was found to be proportional to monomer concentration, dye concentration, and light intensity, but independent of periodate concentration. A mechanism involving initiation by OH radicals and termination by periodate is proposed to explain the results.

Photopolymerization of Acrylonitrile with the Isopropanol-Ag(I) System as Initiator

Abstract Photopolymerization of acrylonitrile was studied with the isopropanol-Ag(I) system as initiator in aqueous medium. The rate of polymerization increased with time and reached a steady state within 10 min. The rate of polymerization was found to be proportional to [acrylonitrile]1.5, [Ag(I)]0.5, and [isopropanol]0.5. A probable mechanism consistent with the observed results is proposed and discussed.

Photopolymerization of acrylonitrile and methyl methacrylate induced by triphenylamine

The photopolymerization of acrylonitrile and methyl methacrylate in the presence of triphenylamine (TPA) has been performed at 30°C in N,N-dimethylformamide and dimethylsulfoxide under irradiation with light of λ > 300 nm. TPA proved to be very effective for the polymerization of both monomers. An apparent activation energy of 4·3 kcal/mol was recorded for the photopolymerization of acrylonitrile. Equations of polymerization derived from a kinetic study were as follows: Rate of polymerization=K[TPA] 1 2 [Monomer] 1·0 Degree of polymerization=K′[TPA] − 1 2 [Monomer] 1·0 From the UV spectrum of photoirradiated TPA in N,N-dimethylformamide solution, the formation of N,N-diphenylamine and aniline was observed, in which the photodecomposition of TPA might result. Based on these results, it was suggested that radicals formed in the process of photodecomposition of TPA are responsible for the initiation of the photopolymerization, which proceeds through an ordinary mechanism of radical polymerization.

Photopolymerization of Acrylonitrile: Benzophenone-Isopropanol System as Initiator

Abstract Irradiation of benzophenone in the presence of a suitable hydrogen donor like alcohol leads to benzpinacol and the ketone as sole products. This reaction proceeds through ketyl radical intermediates. This photoredox system may be used for photopolymerization. Photopolymerization of acrylonitrile using isopropanol and benzophenone combination as initiator has been studied. The formation of the polymer is directly proportional to irradiation time, [acrylonitrile] and [isopropanol]. The rate of polymerization increases with an increase in concentration of benzophenone to an optimum and a further increase in benzophenone concentration decreases the polymerization rate. A suitable mechanism is suggested.

Application of spin trapping technique to radical polymerization—22. N-benzoyloxyimide derivatives as photoinitiators

N-Benzoyloxyimides such as N-benzoyloxysuccinimide (NBzS) were found to act as photoinitiators for acrylonitrile (AN), methyl acrylate and methyl methacrylate. Polymerization rate ( R p) for the photopolymerization of AN with NBzS in dimethylformamide at 30° was expressed thus; R p - k [ NB ZS ] 0.25 [ AN 1.3 The overall activation energy was 27.6 kJ/mol. A spin trapping study on the photolysis of NBzS revealed formation of acyl and phenyl radicals, indicating that simultaneous scissions of the NO and OCO bonds in NBzS occur under irradiation. An initiation mechanism is proposed and discussed.

Photopolymerization of Acrylonitrile by Potassium TrisoxalatocobaItate(III) in Aqueous Perchloric Acid

Abstract Results of a kinetic study on photopolymerization of acrylonitrile by potassium trisoxalatocobaltate(II1) in aqueous perchloric acid medium (pH = 1) by use of light of 365 nm wavelength at 30 |Mg 0.1°C are presented. All reactions were carried out under completely deaerated conditions. Certain important features of the photopolymerization are described. The rate of polymerization Rp was followed by gravimetric estimation of polymer formed and rate of disappearance of complex - Rc by spectrocolorometric estimation of complex disappearing. Rp was found to be directly proportional to [M]3/2, kε 1/2, and I1/2, where P[M], kε, and I refer to concentration of acrylonitrile, light absorption fraction of the complex, and light intensity, respectively. -Rc was found to be directly proportional to kε and I. A reaction scheme is drawn and kinetic expressions derived on the basis of that scheme are given.

Photopolymerization of acrylonitrile in the presence of substituted triphenyl phosphites

AbstractIt was found that acrylonitrile was polymerized at 30°C by ultraviolet irradiation in the presence of triphenyl phosphite and its derivatives, namely m‐CH3, p‐C2H5, and p‐CH3 substituted triphenyl phosphites under conditions where acrylonitrile alone did not polymerize and phosphites did not undergo photolysis. The rate of polymerization in the presence of triphenyl phosphite and tri‐p‐tolyl phosphite was found to be proportional to the monomer concentration, the phosphite concentration, and the light intensity. From these results, it was thought that a donor–acceptor complex formed between phosphite and acrylonitrile which absorbed light and initiated the radical polymerization. In the photopolymerization of acrylonitrile with substituted triphenyl phosphites, the rate of polymerization increased with an increase in electron‐donating ability of substituent. From the plot obtained by use of Hammett's equation (log Rp/Rp0 = ρσ), the ρ value was found to be −1.0.

Photopolymerization. I. Photopolymerization of acrylonitrile in the presence of naphthalene and its derivatives

Journal of Polymer Science: Polymer Letters EditionVolume 12, Issue 6 p. 327-330 Article Photopolymerization. I. Photopolymerization of acrylonitrile in the presence of naphthalene and its derivatives I. Capek, I. Capek Polymer Institute, Slovak Academy of Sciences, 809 34, Bratislava, CzechoslovakiaSearch for more papers by this authorJ. Bartoň, J. Bartoň Polymer Institute, Slovak Academy of Sciences, 809 34, Bratislava, CzechoslovakiaSearch for more papers by this author I. Capek, I. Capek Polymer Institute, Slovak Academy of Sciences, 809 34, Bratislava, CzechoslovakiaSearch for more papers by this authorJ. Bartoň, J. Bartoň Polymer Institute, Slovak Academy of Sciences, 809 34, Bratislava, CzechoslovakiaSearch for more papers by this author First published: June 1974 https://doi.org/10.1002/pol.1974.130120604Citations: 7AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume12, Issue6June 1974Pages 327-330 RelatedInformation

Vinyl Polymerization by Metal Complexes. VIII. On the Kinetics of Photopolymerization of Vinyl Monomers by Fe(III) Salt-Saccharide Systems

Abstract The photopolymerization of acrylonitrile and acrylamide initiated by Fe(III) salt-saccharide systems was studied kinetically in aqueous solution. The interaction between Fe (III) ion and different saccharides was investigated by spectrophometry, and the results are discussed in terms of the problems of complex formation and polymerizability of the initiating systems

Vinyl Polymerization by Metal Complexes. VII

Abstract The photopolymerization of vinyl monomers by metal salt-saccharide system was investigated in various solvents. The rate of polymerization in the presence of a iron(III) salt in aqueous media was remarkably accelerated by the addition of saccharides. The acceleration caused by a series of saccharides was found to be in the following order: glucose > fructose > lactose maltose. α-Methyl-d-glucoside and sucrose exhibited very little effect. The overall activation energy for the photopolymerization of acrylonitrile in the presence of glucose was found to be 2.7 kcal/mole, about half of the value obtained in the absence of glucose.

Effects of trivalent phosphorus compounds on vinyl polymerizations. II. Photopolymerization of acrylonitrile in the presence of triphenylphosphite

AbstractIt was found that acrylonitrile is polymerized by UV irradiation in the presence of triphenylphosphite under conditions where acrylonitrile alone does not polymerize. The rate of polymerization was found to be proportional to the monomer concentration, the phosphite concentration, and the light intensity. It was thought that a donor‐acceptor complex formed between triphenylphosphite and acrylonitrile absorbs light and initiates the radical polymerization.

Photopolymerization of acrylonitrile in dimethyl sulfoxide. I. Inititation by 1,1′‐azodicyclohexanecarbonitrile

Photopolymerization of acrylonitrile in dimethyl sulfoxide. I. Inititation by 1,1′‐azodicyclohexanecarbonitrile

Photopolymérisation du nitrile acrylique en présence des sels de lanthane

AbstractData are given for the photopolymerization of acrylonitrile in the presence of some lanthanium salts, as initiators of the polymerization. The activity of these salts with respect to the photopolymerization of acrylonitrile indicates the following series: LaCl3 · H2O > La2(SO4)3 · 9H2O > La(NO3)3 · 6H2O > La(CH3COO)3. The kinetics of the process have also been considered.

Photopolymerization of acrylonitrile in a homogeneous medium : K. Simionesku, D. Fel'dman and F. Shandru, Vysokomol. soyed. 5: No. 3, 460–466, 1963

Photopolymerization of acrylonitrile in a homogeneous medium : K. Simionesku, D. Fel'dman and F. Shandru, Vysokomol. soyed. 5: No. 3, 460–466, 1963