Acrylic acid Carbon dioxide

This compound can be thermally redecomposed into acetic and acrylic acids, carbon dioxide, polymers, propionic acid, vinyl acetate and acetaldehyde. 

Poly [2-(perfluorooctyl)ethyl acrylate-coacrylic acid] carbon dioxide 2008YOS... 

In 1968, a French Patent issued to the Sumitomo Chemical Company disclosed the polymerization of several vinyl monomers in C02 [84], The United States version of this patent was issued in 1970, when Fukui and coworkers demonstrated the precipitation polymerization of several hydrocarbon monomers in liquid and supercritical C02 [85], As examples of this methodology, they demonstrated the preparation of the homopolymers PVC, PS, poly(acrylonitrile) (PAN), poly(acrylic acid) (PAA), and poly(vinyl acetate) (PVAc). In addition, they prepared the random copolymers PS-co-PMMA and PVC-co-PVAc. In 1986, the BASF Corporation was issued a Canadian Patent for the preparation of polymer powders through the precipitation polymerization of monomers in carbon dioxide at superatmospheric pressures [86], Monomers which were polymerized as examples in this patent included 2-hydroxyethylacrylate and iV-vinylcarboxamides such as iV-vinyl formamide and iV-vinyl pyrrolidone. 

POLYCARBOXYLIC ACIDS The gamma radiolysis of the homopolymers of acrylic, methacrylic and itaconic acids have been investigated in the solid state at 303 K, and in each case the yields of carbon monoxide, carbon dioxide and of radical intermediates have been measured. These are reported in Tables VII and VIII respectively. 

Acrolein is immediately passed through a second oxidation reactor to form acrylic acid. The reaction talces place at 475-575 E, over a tin-antimony oxide catalyst. A few by-products form, namely, formic acid (HCOOH), acetic acid (CH3COOH), low molecular weight polymers, carbon monoxide, and dioxide. But overall yields of propylene to acrylic acid are high—85 to 90%. 

Black KA, Finch L, Frederick CB Metabolism of acrylic acid to carbon dioxide in mouse tissues. Fundam Appl Toxicol 21 97-104, 1993... 

Cyclic amino acids 139, when heated in acetic anhydride, probably form initially mesoionic oxazolium 5-oxides (munchnones) subsequent 1,3-dip olar cycloaddition of 1,2-dicyanocyclobutene, loss of carbon dioxide, and opening of the cyclobutane ring lead to dinitriles 140 (80JHC1593). Pyridone 141 is the by-product (together with an indolizine) of the mono-cyclic pyridone dicarboxylate and acrylic ester (73JHC77). 

O Oxygen consumed X 2 V Peracrylic acid X 10 A Acrolein consumed Polymers X 2/5 Acrylic acid 3 Carbon dioxide C Carbon monoxide A Acetic acid... 

As stated above, various authors have confirmed the extensive conversion of acrylic acid to carbon dioxide in rats and mice treated orally or topically. In addition, urinary metabolites include 3-hydroxypropionic acid and the mercapturic acid A-acet l-.S -(2-carboxyethyljcysteine and its. S -oxide (DeBethizy et al., 1987 Winter et al., 1993). 

Finch, L. Frederick, C.B. (1992) Rate and route of oxidation of acrylic acid to carbon dioxide in rat liver. Fundam. appl. Toxicol., 19, 498-505... 

Oxidation of the allylic carbon of alkenes may lead to allylic alcohols and derivatives or a, 3-unsaturated carbonyl compounds. Selenium dioxide is the reagent of choice to carry out the former transformation. In the latter process, which is more difficult to accomplish, Cr(VI) compounds are usually applied. In certain cases, mixture of products of both types of oxidation, as well as isomeric compounds resulting from allylic rearrangement, may be formed. Oxidation of 2-alkenes to the corresponding cc,p-unsaturated carboxylic acids, particularly the oxidation of propylene to acrolein and acrylic acid, as well as ammoxidation to acrylonitrile, has commercial importance (see Sections 9.5.2 and 9.5.3). 

The main by-products of acrolein formation are carbon monoxide and carbon dioxide, as well as minor amounts of acrylic acid and lower aldehydes and acids. Combustion takes place both consecutive and parallel to the main reaction. Acrylic acid (in free or adsorbed form) is a possible intermediate in the acrolein combustion. Including this product, the following simplified scheme applies. 

Romack, T. J. Maury, E. E. DeSimone, J. M. Precipitation Polymerization of Acrylic Acid in Supercritical Carbon Dioxide. Macromolecules 1995, 28, 912. 

The principal side reactions produce acrylic acid, acetaldehyde, acetic acid, carbon monoxide, and carbon dioxide, and a variety of other aldehydes and acids are also formed in small amounts. 

Phase behavior studies with poly(ethylene-co-methyl acrylate), poly (ethylene-co-butyl acrylate), poly(ethylene-co-acrylic add), and poly(ethylene-co-methacrylic acid) were performed in the normal alkanes, their olefinic analogs, dimethyl ether, chlorodifluoromethane, and carbon dioxide up to 250 °C and 2,700 bar. The backbone architecture of the copolymers as well as the solvent quality greatly influences the solution behavior in supercritical fluids. The effect of cosolvent was also studied using dimethyl ether and ethanol as cosolvent in butane at varying concentrations of cosolvent, exhibiting that the cosolvent effect diminishes with increasing cosolvent concentrations. 

In this paper first results of the solubility and extraction of low molecular weight polymers and plasticizers with supercritical carbon dioxide are presented and compared to the results of phase equilibria measurements. Additionally the formation of sub-micrometer particles during polymerization of acrylic acid and derivatives thereof in scCC are examined and compared with recent works [2], Finally there are some aspects to modification of polymers by absorption of scC02 and reactive components solved therein. 

POLYMERIZATION AND POLYMER MODIFICATION 2.1. Polymerization of acrylic acid in supercritical carbon dioxide... 

As a comparison and reproduction to recent works done by DeSimone and coworkers [2], attempts were made in the free radical polymerization of acrylic acid (AA) in supercritical carbon dioxide (SCCO2) with Azoisobutyronitrile (AIBN) as initiator. 

The reaction is very exotliemiic. The heat of reaction of propylene oxidation to acrolein is 340.8 kj/mol (81.5 kcal/mol) the overall reactions generate approximately 837 kj/mol (200 kcal/mol). The principal side reactions produce acrylic acid, acetaldehyde, acetic acid, carbon monoxide, and carbon dioxide. A variety of other aldehydes and acids are also fomied in small amounts. Proprietary processes for acrolein manufacture have been... 

Oxidative Carbonylation of Ethylene—Elimination of Alcohol from p-Alkoxypropionates. Spectacular progress in the 1970s led to the rapid development of organotransition-metal chemistry, particularly to catalyze olefin reactions (93,94). A number of patents have been issued (28,95—97) for the oxidative carbonylation of ethylene to provide acrylic acid and esters. The procedure is based on the palladium catalyzed carbonylation of ethylene in the liquid phase at temperatures of 50—200°C. Esters are formed when alcohols are included. Anhydrous conditions are desirable to minimize the formation of by-products including acetaldehyde and carbon dioxide (see Acetaldehyde). 

At a one-to-one pressure ratio of ethylene to<arbon monoxide of around 1000 psig, the major product is succinate this is in contrast to the production of acrylic acid, where succinic add was not isolated. If the olefin is left out of the reaction mix, then oxalates are produced and this is a practical route to oxalates, particularly at carbon monoxide pressures above 500 psig. The formation of water is a severe problem for the stability and activity of the catalytic system, since in the presence of water there is a parallel reaction which produces considerable amounts of carbon dioxide. 

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