Reaction Of Acrylic Acid Research Articles

Synthesis of polybutadiene-acrylates and properties of the photocured films

The acrylation of polybutadienes was performed by reaction of acrylic acid with epoxy, epoxy-hydroxyl functionalized and hydroxyl-terminated oligomers. Some epoxy-functionalized oligomers were previously obtained by epoxidation of a liquid 1,4-polybutadiene. The properties of the acrylated products were affected by the oligomer type and the reaction procedure. The UV-curing of these products was studied by FTIR and thermal analyses, which showed the amorphous and rubbery nature of the resulting films. In some cases, the double bonds conversion was increased by a thermal post-curing, but the adhesion properties were strongly reduced. The swelling of the UV-cured films was studied by varying the solvent polarity. The mixtures of some polybutadiene-acrylates with a typical epoxy-acrylic resin gave highly cross-linked films showing a flexibilizing effect due to the polybutadiene oligomers which can act as reactive diluents.

Adsorption of VO2+ by poly[(tetrafluoroethylene)-co-(perfluorovinyl ether)] copolymer grafted with acrylic acid usingγ-irradiation

Grafted films were prepared by the reaction of acrylic acid (AAc) onto poly[(tetrafluoroethylene)-co-(perfluorovinyl ether)] copolymer (PFA) using γ-irradiation by the mutual technique. The grafted copolymer was complexed with the vanadyl group, VO2+, in aqueous solution. The grafted copolymer–metal complexes were examined by infrared and ultraviolet spectrometry, energy-dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The amount of vanadium in the grafted films was estimated using EDS. The thermal stability of the films was investigated through thermogravimetric and differential scanning calorimetry measurements. The degree of crystallinity of the grafted and complexed films decreased by treatment with VO2+ ions and also by heating at 300 °C. When heated at a temperature above 300 °C, the grafted chains degraded till they disappeared and the original polymer was almost completely separated. XRD investigation revealed that the metal oxide may be formed as a separate phase with subsequent decrease in the crystallinity of the copolymer. Furthermore, scanning electron microscope (SEM) investigation of the grafted and modified films, both unheated and heated (300 °C), showed changes in the structure and morphology. The tendency of the graft copolymer to adsorb and/or bind to VO2+ from aqueous solution is of promising use in the field of waste treatment of rare metals in the environment. Copyright © 2004 Society of Chemical Industry

Gas chromatographic investigation of acrylamide formation in browning model systems.

Acrylamide formed in browning model systems was analyzed using a gas chromatograph with a nitrogen-phosphorus detector. Asparagine alone produced acrylamide via thermal degradation at the level of 0.99 microgram/g of asparagine. When asparagine was heated with triolein-which produced acrolein at the level of 1.82 +/- 0.31 (n = 5) mg/L of headspace by heat treatment-acrylamide was formed at the level of 88.6 microgram/g of asparagine. When acrolein gas was sprayed onto asparagine heated at 180 degrees C, a significant amount of acrylamide was formed (114 microgram/g of asparagine). On the other hand, when acrolein gas was sprayed onto glutamine under the same conditions, only a trace amount of acrylamide was formed (0.18 microgram/g of glutamine). Relatively high levels of acrylamide (753 microgram/g of ammonia) were formed from ammonia and acrolein heated at 180 degrees C in the vapor phase. The reaction of acrylic acid, which is an oxidation product of acrolein and ammonia, produced a high level of acrylamide (190 000 microgram/g of ammonia), suggesting that ammonia and acrolein play an important role in acrylamide formation in lipid-rich foods. Acrylamide can be formed from asparagine alone via thermal degradation, but carbonyl compounds, such as acrolein, promote its formation via a browning reaction.

The novel low temperature synthesis of nanocrystalline MgAl 2O 4 spinel using “gel” precursors

Nanocrystalline MgA1 2O 4 was synthesized by pyrolysis of the homogeneous spinel precursor, Mg(C 4H 5O 2) 2·(H 2O):Al 2(OH) 3(C 3H 3O 2) 3·(H 2O) 2:NH 4(C 3H 3O 2)·(H 2O). The spinel precursor gel is composed of a mixture of magnesium and aluminum acrylate salts dissolved in an ammonium acrylate gel. The reaction of acrylic acid with magnesium hydroxide in water produced magnesium methacrylate, and a similar reaction of basic aluminum acetate produced the aluminum salt of acrylic acid. The reaction of acrylic acid with ammonium hydroxide produced the ammonium acrylate gel. Ammonium acrylate gel was found to absorb many times its own weight of water. Although similar properties have been identified in PMMA and in the polymer of sodium acrylate, only the ammonium acrylate gel exists as an unpolymerized monomer. The spinel precursor gel is a pre-ceramic material that yields an amorphous oxide phase at 425°C that begins to crystallize to the MgAl 2O 4 spinel at 600°C and is fully crysta1line at 1030°C with a uniform particle size of 7–100 nm. The spinel precursor gel and the nanocrystalline MgA1 2O 4 spinel were characterized by XRD and TEM.

Reaction of Acrylic Acid on TiO2(001) Single Crystal Surfaces. Evidence of Different Pathways for Vinyl and Carboxyl Groups

The TiO2(001) single crystal surface is unique in that surface structure, coordination number of titanium cations, and degree of reduction may be easily controlled by varying the annealing temperature in ultrahigh vacuum. In an effort to understand the chemical pathways of conjugated molecules over the surfaces of semiconductors, the complementary techniques of temperature-programmed desorption, X-ray photoelectron spectroscopy, and scanning kinetic spectroscopy have been applied to study the interaction and surface chemistry of CH2CHCOOH with the TiO2(001) single crystal surface in detail. A clear difference is observed between the reaction of this unsaturated carboxylic acid and that of saturated analogues. Two different coupling pathways were observed. The first, involving the H2CCH moiety, generated C4 and C6 hydrocarbon products (butene, butadiene, and benzene). The second results in the production of divinyl ketone, formed by ketonization of two adsorbed acrylate molecules at a doubly coordinatively unsaturated titanium center on the {114}-faceted TiO2(001) surface only.

Molecular parameters and their relation to the adhesive performance of acrylic pressure-sensitive adhesives

Model acrylic pressure-sensitive adhesives (PSAs) based on poly(2-ethyl-hexyl acrylate-stat-acrylic acid) and poly(n-butyl acrylate-stat-acrylic acid) at 97.5/2.5 wt % were synthesized using semicontinuous emulsion and solution polymerizations. Microgels formed in the lattices retained their discrete network morphology in the film. In contrast, acrylic solution was essentially gel free and crosslinking in the film was provided by the reaction of acrylic acid and post added Al Acetyl Acetonate after solvent evaporation, which led to continuous network morphology. The difference in film network morphology caused significantly lower shear holding power for the film from emulsion PSA compared with that of solvent-borne film. Unlike shear holding power, loop tack and peel of acrylic PSAs were mainly controlled by the same sol/gel molecular parameters, regardless of emulsion or solution PSAs. The important molecular parameters are sol-to-gel ratio, entanglement molecular weight, weight average molecular weight, and to a lesser extent, glass transition temperature. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 79: 2230–2244, 2001

Reaction of the acrylic acid and 1-vinylimidazole copolymer with CuCl2 in aqueous solution

The reaction of acrylic acid—1-vinylimidazole copolymer with CuCl2 in an aqueous medium was investigated by potentiometric titration and UV and ESR spectroscopy. The complex formation involves both the azole units and the carboxy groups. The Cl– ions are also incorporated in the inner sphere of the complexes, their removal by dialysis resulting in an increase in the coordination capacity of the carboxylate groups.

Preparation and reactivity of metal-containing monomers

The monomer [Cr3O(OCOCH=CH2)6]OH was produced by reaction of acrylic acid with fresh chromium hydroxide. This monomer was investigated by a number of physicochemical methods. It was found that acrylate residues are bonded to the metal atomsvia the carboxy group so that the double bond is not involved in coordination. A comparative study of the dissociative fragmentation of the [M3OAcr6]+ clusters, where M is Cr or Fe and Acr is OCOCH=CH2, shows that in the case of Fe the [M3OAcr3]+ fragment is the main product of decomposition of [M3OAcr3]+ cluster cation, whereas this was not observed in the case of Cr. The [M2OAcr4]+ fragments are characteristic of decomposition products of the Cr complex and do not form in the case of Fe. The radical polymerization of Cr-containing monomers results in monodentate coordination of the carboxy groups, which does not appear in the initial monomer.

Binary copolymerizations of N‐acryloyloxyphthalimide with methyl acrylate, methyl methacrylate and acrylonitrile

AbstractN‐Acryloyloxyphthalimide was prepared by the reaction of acrylic acid with N‐hydroxyphthalimide in the presence of N,N′‐dicyclohexylcarbodiimide. The monomer reactivity ratios for the copolymerization of N‐acryloyloxyphthalimide with methyl acrylate, methyl methacrylate, and acrylonitrile, respectively, were estimated by 1H‐NMR spectroscopic data. The Q‐ and e‐ values for N‐acryloyloxyphthalimide were calculated.

Influence des solvants sur la copolymerisation de l'acide acrylique avec l'acrylonitrile et l'acrylamide

The copolymerizations of acrylic acid with acrylonitrile and acrylamide were studied in the presence of various solvents. All three monomers form molecular associations with themselves and with other polar molecules present in the system, such as the comonomer and many solvents. A gradual dilution of the monomers in a solvent changes the equilibria of the various associations involved and affects simultaneously the kinetics and the composition of the resulting copolymer. The very complicated kinetics observed in this study result from physical modifications of the reacting medium. The composition of the copolymers varies greatly with the nature of the solvent used in the case of the acrylic acid-acrylamide pair whereas it only has a small influence in the reaction of acrylic acid with acrylonitrile. The results are discussed and compared with earlier studies in the field.

ChemInform Abstract: Esterification of Acrylic Acid with Methanol over Niobic Acid Catalyst.

Abstract The esterification of acrylic acid with methanol and the hydrolysis of the ester were examined over niobic acid preheated at different temperatures. Niobic acid pretreated at 200 – 400°C showed a high activity and selectivity (⋍100%) for both reactions. In the reaction of acrylic acid with excess methanol, niobic acid could maintain the conversion of more than 90% for 6 h or more.

Esterification of acrylic acid with methanol over niobic acid catalyst

The esterification of acrylic acid with methanol and the hydrolysis of the ester were examined over niobic acid preheated at different temperatures. Niobic acid pretreated at 200 – 400°C showed a high activity and selectivity (⋍100%) for both reactions. In the reaction of acrylic acid with excess methanol, niobic acid could maintain the conversion of more than 90% for 6 h or more.

Enamine chemistry. Part XI. Reaction of αβ-unsaturated acids and acid chlorides with imines. Synthesis of 2-oxotetrahydropyridines and 2-oxo-octahydroquinolines

2-Oxotetrahydropyridines and 2-oxo-octahydroquinolines have been isolated from the reaction of acryloyl chloride with imines, together with the enamide and, in some cases, the amide. Crotonoyl and cinnamoyl chlorides give mixtures consisting mainly of the enamides. 2-Oxotetrahydropyridines and 2-oxo-octahydroquinolines have also been isolated from the reaction of acrylic acid with imines. The mechanisms of these reactions are discussed.