Acrylic acid

Last updated
Acrylic acid [1]
Acrylic acid.svg
Acrylic-acid-from-xtal-3D-balls.png
Names
IUPAC name
Acrylic acid [2]
Preferred IUPAC name
Prop-2-enoic acid [2]
Other names
  • Acrylic acid
  • Acroleic acid
  • Ethylenecarboxylic acid
  • Propenoic acid
  • Vinylformic acid
  • Methyleneacetic acid
Identifiers
3D model (JSmol)
635743
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard 100.001.071 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 201-177-9
1817
KEGG
PubChem CID
RTECS number
  • AS4375000
UNII
  • InChI=1S/C3H4O2/c1-2-3(4)5/h2H,1H2,(H,4,5) Yes check.svgY
    Key: NIXOWILDQLNWCW-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/C3H4O2/c1-2-3(4)5/h2H,1H2,(H,4,5)
    Key: NIXOWILDQLNWCW-UHFFFAOYAJ
  • O=C(O)C=C
  • C=CC(=O)O
Properties
C3H4O2
Molar mass 72.063 g/mol
AppearanceClear, colorless liquid
Odor Acrid [3]
Density 1.051 g/mL
Melting point 14 °C (57 °F; 287 K)
Boiling point 141 °C (286 °F; 414 K)
Miscible
log P 0.28 [4]
Vapor pressure 3 mmHg [3]
Acidity (pKa)4.25 (H2O) [5]
Viscosity 1.3  cP at 20 °C (68 °F)
Hazards
GHS labelling:
GHS-pictogram-flamme.svg GHS-pictogram-acid.svg GHS-pictogram-exclam.svg GHS-pictogram-skull.svg GHS-pictogram-pollu.svg
Danger
H226, H302, H312, H314, H332, H400
P210, P233, P240, P241, P242, P243, P260, P261, P264, P270, P271, P273, P280, P301+P312, P301+P330+P331, P302+P352, P303+P361+P353, P304+P312, P304+P340, P305+P351+P338, P310, P312, P321, P322, P330, P363, P370+P378, P391, P403+P235, P405, P501
NFPA 704 (fire diamond)
NFPA 704.svgHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 2: Must be moderately heated or exposed to relatively high ambient temperature before ignition can occur. Flash point between 38 and 93 °C (100 and 200 °F). E.g. diesel fuelInstability 2: Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water. E.g. white phosphorusSpecial hazards (white): no code
3
2
2
Flash point 68 °C (154 °F; 341 K)
429 °C (804 °F; 702 K)
Explosive limits 2.4–8.02% [3]
NIOSH (US health exposure limits):
PEL (Permissible)
None [3]
REL (Recommended)
TWA 2 ppm (6 mg/m3) [skin] [3]
IDLH (Immediate danger)
N.D. [3]
Safety data sheet (SDS) MSDS
Related compounds
Other anions
acrylate
acetic acid
propionic acid
lactic acid
3-hydroxypropionic acid
malonic acid
butyric acid
crotonic acid
Related compounds
allyl alcohol
propionaldehyde
acrolein
methyl acrylate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Yes check.svgY  verify  (what is  Yes check.svgYX mark.svgN ?)

Acrylic acid (IUPAC: propenoic acid) is an organic compound with the formula CH2=CHCOOH. It is the simplest unsaturated carboxylic acid, consisting of a vinyl group connected directly to a carboxylic acid terminus. This colorless liquid has a characteristic acrid or tart smell. It is miscible with water, alcohols, ethers, and chloroform. More than a million tons are produced annually. [6]

Contents

History

The word "acrylic" was coined in 1843, for a chemical derivative of acrolein, an acrid-smelling oil derived from glycerol.

Production

Acrylic acid is produced by oxidation of propylene, which is a byproduct of the production of ethylene and gasoline:

2 CH2=CHCH3 + 3 O2 → 2 CH2=CHCO2H + 2 H2O

Historical methods

Because acrylic acid and its esters have long been valued commercially, many other methods have been developed. Most have been abandoned for economic or environmental reasons. An early method was the hydrocarboxylation of acetylene ("Reppe chemistry"):

Acrylic acid synthesis from acethylene.png

This method requires nickel carbonyl, high pressures of carbon monoxide, and acetylene, which is relatively expensive compared to propylene.

Acrylic acid was once manufactured by the hydrolysis of acrylonitrile, a material derived from propene by ammoxidation, but this route was abandoned because it cogenerates ammonium side products, which must be disposed of. Other now abandoned precursors to acrylic acid include ethenone and ethylene cyanohydrin. [6]

Research

Propane is a much cheaper raw material than propylene, so an alternative route being explored is the one-step selective oxidation of propane. [7]

Carboxylating ethylene to acrylic acid under supercritical carbon dioxide is thermodynamically possible, but efficient catalysts have not been developed. [8] 3-Hydroxypropionic acid (3HP), an acrylic-acid precursor by dehydration, can be produced from sugars, but the process is not competitive. [9] [10]

Reactions and uses

Acrylic acid undergoes the typical reactions of a carboxylic acid. When reacted with an alcohol, it forms the corresponding ester. The esters and salts of acrylic acid are collectively known as acrylates (or propenoates). The most common alkyl esters of acrylic acid are methyl, butyl, ethyl, and 2-ethylhexyl acrylate.

Acrylic acid and its esters readily combine with themselves (to form polyacrylic acid) or other monomers (e.g. acrylamides, acrylonitrile, vinyl compounds, styrene, and butadiene) by reacting at their double bond, forming homopolymers or copolymers, which are used in the manufacture of various plastics, coatings, adhesives, elastomers, as well as floor polishes and paints.

Acrylic acid is used in many industries, including the diaper industry, the water treatment industry, and the textiles industry. The annual worldwide consumption of acrylic acid is projected to reach more than an estimated 8,000 kilotons by 2020. This increase is expected due to its use in new applications, including personal care products, detergents, and products for adult incontinence. [11]

Substituents

As a substituent acrylic acid can be found as an acyl group or a carboxyalkyl group, depending on the removal of the group from the molecule.

More specifically, these are:

  1. The acryloyl group, with the removal of the −OH from carbon-1.
  2. The 2-carboxyethenyl group, with the removal of a −H from carbon-3. This substituent group is found in chlorophyll.

Safety

Acrylic acid is severely irritating and corrosive to the skin and the respiratory tract. Eye contact can result in severe and irreversible injury. Low exposure will cause minimal or no health effects, while high exposure could result in pulmonary edema. The LD50 is 340 mg/kg (rat, oral) with the lowest recorded LD50 being 293 mg/kg (oral, rat) comparable to ethylene glycol which is indicative of being a potent poison. [12] Ethyl acrylate was once used as synthetic food flavoring and was withdrawn by FDA possibly due to cancerogenic effects observed in lab animals. [13]

Animal studies showed that high-doses of acrylic acid decreased weight gain. Acrylic acid can be converted to non-toxic lactic acid. [14]

Acrylic acid is a constituent of tobacco smoke. [15]

See also

Related Research Articles

<span class="mw-page-title-main">Alcohol (chemistry)</span> Organic compound with at least one hydroxyl (–OH) group

In chemistry, an alcohol is a type of organic compound that carries at least one hydroxyl functional group bound to a saturated carbon atom. Alcohols range from the simple, like methanol and ethanol, to complex, like sucrose and cholesterol. The presence of an OH group strongly modifies the properties of hydrocarbons, conferring hydrophilic (water-loving) properties. The OH group provides a site at which many reactions can occur.

<span class="mw-page-title-main">Ester</span> Compound derived from an acid

In chemistry, an ester is a compound derived from an acid in which the hydrogen atom (H) of at least one acidic hydroxyl group of that acid is replaced by an organyl group. Analogues derived from oxygen replaced by other chalcogens belong to the ester category as well. According to some authors, organyl derivatives of acidic hydrogen of other acids are esters as well, but not according to the IUPAC.

<span class="mw-page-title-main">Ketone</span> Organic compounds of the form >C=O

In organic chemistry, a ketone is an organic compound with the structure R−C(=O)−R', where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group −C(=O)−. The simplest ketone is acetone, with the formula (CH3)2CO. Many ketones are of great importance in biology and in industry. Examples include many sugars (ketoses), many steroids, and the solvent acetone.

<span class="mw-page-title-main">Petrochemical</span> Chemical product derived from petroleum

Petrochemicals are the chemical products obtained from petroleum by refining. Some chemical compounds made from petroleum are also obtained from other fossil fuels, such as coal or natural gas, or renewable sources such as maize, palm fruit or sugar cane.

In chemistry, a hydration reaction is a chemical reaction in which a substance combines with water. In organic chemistry, water is added to an unsaturated substrate, which is usually an alkene or an alkyne. This type of reaction is employed industrially to produce ethanol, isopropanol, and butan-2-ol.

Acrylonitrile is an organic compound with the formula CH2CHCN and the structure H2C=CH−C≡N. It is a colorless, volatile liquid. It has a pungent odor of garlic or onions. Its molecular structure consists of a vinyl group linked to a nitrile. It is an important monomer for the manufacture of useful plastics such as polyacrylonitrile. It is reactive and toxic at low doses.

Acrylates are the salts, esters, and conjugate bases of acrylic acid. The acrylate ion is the anion CH2=CHCO−2. Often, acrylate refers to esters of acrylic acid, the most common member being methyl acrylate. These acrylates contain vinyl groups. These compounds are of interest because they are bifunctional: the vinyl group is susceptible to polymerization and the carboxylate group carries myriad functionalities.

In chemical nomenclature, the IUPAC nomenclature of organic chemistry is a method of naming organic chemical compounds as recommended by the International Union of Pure and Applied Chemistry (IUPAC). It is published in the Nomenclature of Organic Chemistry. Ideally, every possible organic compound should have a name from which an unambiguous structural formula can be created. There is also an IUPAC nomenclature of inorganic chemistry.

A diol is a chemical compound containing two hydroxyl groups. An aliphatic diol is also called a glycol. This pairing of functional groups is pervasive, and many subcategories have been identified.

Propylene, also known as propene, is an unsaturated organic compound with the chemical formula CH3CH=CH2. It has one double bond, and is the second simplest member of the alkene class of hydrocarbons. It is a colorless gas with a faint petroleum-like odor.

In chemistry, homogeneous catalysis is catalysis where the catalyst is in same phase as reactants, principally by a soluble catalyst a in solution. In contrast, heterogeneous catalysis describes processes where the catalysts and substrate are in distinct phases, typically solid-gas, respectively. The term is used almost exclusively to describe solutions and implies catalysis by organometallic compounds. Homogeneous catalysis is an established technology that continues to evolve. An illustrative major application is the production of acetic acid. Enzymes are examples of homogeneous catalysts.

<span class="mw-page-title-main">Methyl methacrylate</span> Chemical compound

Methyl methacrylate (MMA) is an organic compound with the formula CH2=C(CH3)COOCH3. This colorless liquid, the methyl ester of methacrylic acid (MAA), is a monomer produced on a large scale for the production of poly(methyl methacrylate) (PMMA).

<span class="mw-page-title-main">Acryloyl chloride</span> Chemical compound

Acryloyl chloride, also known as 2-propenoyl chloride, acrylyl chloride, or acrylic acid chloride, is the organic compound with the formula CH2=CHCO(Cl). It is a colorless liquid, although aged samples appear yellow. It belongs to the acid chlorides group of compounds.

<span class="mw-page-title-main">Carbonate ester</span> Chemical group (R–O–C(=O)–O–R)

In organic chemistry, a carbonate ester is an ester of carbonic acid. This functional group consists of a carbonyl group flanked by two alkoxy groups. The general structure of these carbonates is R−O−C(=O)−O−R' and they are related to esters, ethers and also to the inorganic carbonates.

<span class="mw-page-title-main">Methacrylic acid</span> Chemical compound

Methacrylic acid, abbreviated MAA, is an organic compound with the formula CH2=C(CH3)CO2H. This colorless, viscous liquid is a carboxylic acid with an acrid unpleasant odor. It is soluble in warm water and miscible with most organic solvents. Methacrylic acid is produced industrially on a large scale as a precursor to its esters, especially methyl methacrylate (MMA), and to poly(methyl methacrylate) (PMMA).

<span class="mw-page-title-main">Ethyl acrylate</span> Chemical compound

Ethyl acrylate is an organic compound with the formula CH2CHCO2CH2CH3. It is the ethyl ester of acrylic acid. It is a colourless liquid with a characteristic acrid odor. It is mainly produced for paints, textiles, and non-woven fibers. It is also a reagent in the synthesis of various pharmaceutical intermediates.

<span class="mw-page-title-main">Methyl acrylate</span> Chemical compound

Methyl acrylate is an organic compound, more accurately the methyl ester of acrylic acid. It is a colourless liquid with a characteristic acrid odor. It is mainly produced to make acrylate fiber, which is used to weave synthetic carpets. It is also a reagent in the synthesis of various pharmaceutical intermediates. Owing to the tendency of methyl acrylate to polymerize, samples typically contain an inhibitor such as hydroquinone.

Butyl acrylate is an organic compound with the formula C4H9O2CCH=CH2. A colorless liquid, it is the butyl ester of acrylic acid. It is used commercially on a large scale as a precursor to poly(butyl acrylate). Especially as copolymers, such materials are used in paints, sealants, coatings, adhesives, fuel, textiles, plastics, and caulk.

Dimethylaminoethyl acrylate or DMAEA is an unsaturated carboxylic acid ester having a tertiary amino group. It is a colorless to yellowish, water-miscible liquid with a pungent, amine-like odor. DMAEA is an important acrylic monomer that gives basic properties to copolymers.

α,β-Unsaturated carbonyl compound Functional group of organic compounds

α,β-Unsaturated carbonyl compounds are organic compounds with the general structure (O=CR)−Cα=Cβ-R. Such compounds include enones and enals, but also carboxylic acids and the corresponding esters and amides. In these compounds, the carbonyl group is conjugated with an alkene. Unlike the case for carbonyls without a flanking alkene group, α,β-unsaturated carbonyl compounds are susceptible to attack by nucleophiles at the β-carbon. This pattern of reactivity is called vinylogous. Examples of unsaturated carbonyls are acrolein (propenal), mesityl oxide, acrylic acid, and maleic acid. Unsaturated carbonyls can be prepared in the laboratory in an aldol reaction and in the Perkin reaction.

References

  1. Merck Index , 11th Edition, 124.
  2. 1 2 International Union of Pure and Applied Chemistry (2014). Nomenclature of Organic Chemistry: IUPAC Recommendations and Preferred Names 2013. The Royal Society of Chemistry. p. 746. doi:10.1039/9781849733069. ISBN   978-0-85404-182-4.
  3. 1 2 3 4 5 6 NIOSH Pocket Guide to Chemical Hazards. "#0013". National Institute for Occupational Safety and Health (NIOSH).
  4. "Acrylic acid_msds".
  5. Dippy, J. F. J.; Hughes, S. R. C.; Rozanski, A. (1959). "The dissociation constants of some symmetrically disubstituted succinic acids". Journal of the Chemical Society: 2492–2498. doi:10.1039/JR9590002492.
  6. 1 2 Ohara, Takashi; Sato, Takahisa; Shimizu, Noboru; Prescher, Günter; Schwind, Helmut; Weiberg, Otto; Marten, Klaus; Greim, Helmut (2003). "Acrylic Acid and Derivatives". Ullmann's Encyclopedia of Industrial Chemistry . Weinheim: Wiley-VCH. doi:10.1002/14356007.a01_161.pub2. ISBN   978-3527306732.
  7. Védrine, Jacques (2017-11-10). "Heterogeneous Catalysis on Metal Oxides". Catalysts. MDPI AG. 7 (11): 341. doi: 10.3390/catal7110341 . ISSN   2073-4344.
  8. Sakakura, Toshiyasu; Choi, Jun-Chul; Yasuda, Hiroyuki (13 June 2007). "Transformation of Carbon dioxide". Chemical Reviews. 107 (6): 2365–2387. doi:10.1021/cr068357u. PMID   17564481.
  9. Sweet Deal: Dow and Partner Cook up Sugar-to-Acrylic Plan. Durabilityanddesign.com. Retrieved on 2012-05-24.
  10. Better Bugs to Make Plastics, Technology Review, September 20, 2010, retrieved January 9, 2012. Technologyreview.com (2010-09-20). Retrieved on 2012-05-24.
  11. "Acrylic acid market" . Retrieved 2018-05-30.
  12. "Webwiser Acrylic Acid".
  13. "Synthetic food flavorings law update".
  14. "Provisional Peer-Reviewed Toxicity Values for Acrylic Acid" (PDF). www.google.com. Retrieved 2022-04-29.
  15. Talhout, Reinskje; Schulz, Thomas; Florek, Ewa; Van Benthem, Jan; Wester, Piet; Opperhuizen, Antoon (2011). "Hazardous Compounds in Tobacco Smoke". International Journal of Environmental Research and Public Health. 8 (12): 613–628. doi: 10.3390/ijerph8020613 . ISSN   1660-4601. PMC   3084482 . PMID   21556207.