Names | |
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IUPAC name Acrylic acid [2] | |
Preferred IUPAC name Prop-2-enoic acid [2] | |
Other names
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Identifiers | |
3D model (JSmol) | |
635743 | |
ChEBI | |
ChEMBL | |
ChemSpider | |
DrugBank | |
ECHA InfoCard | 100.001.071 |
EC Number |
|
1817 | |
KEGG | |
PubChem CID | |
RTECS number |
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UNII | |
UN number | 2218 |
CompTox Dashboard (EPA) | |
| |
| |
Properties | |
C3H4O2 | |
Molar mass | 72.063 g/mol |
Appearance | Clear, 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: | |
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) | |
Flash point | 49.4 [6] °C (120.9 °F; 322.5 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 |
Related carboxylic acids | 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). |
Acrylic acid (IUPAC: prop-2-enoic 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. [7]
The word "acrylic" was coined in 1843, for a chemical derivative of acrolein, an acrid-smelling oil derived from glycerol.
Acrylic acid is produced by oxidation of propylene, which is a byproduct of the production of ethylene and gasoline:
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"):
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. [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]
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 textile 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]
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:
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]
In organic chemistry, an alkyne is an unsaturated hydrocarbon containing at least one carbon—carbon triple bond. The simplest acyclic alkynes with only one triple bond and no other functional groups form a homologous series with the general chemical formula CnH2n−2. Alkynes are traditionally known as acetylenes, although the name acetylene also refers specifically to C2H2, known formally as ethyne using IUPAC nomenclature. Like other hydrocarbons, alkynes are generally hydrophobic.
In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom bonded to two organyl groups. They have the general formula R−O−R′, where R and R′ represent the organyl groups. Ethers can again be classified into two varieties: if the organyl groups are the same on both sides of the oxygen atom, then it is a simple or symmetrical ether, whereas if they are different, the ethers are called mixed or unsymmetrical ethers. A typical example of the first group is the solvent and anaesthetic diethyl ether, commonly referred to simply as "ether". Ethers are common in organic chemistry and even more prevalent in biochemistry, as they are common linkages in carbohydrates and lignin.
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. These compounds contain a distinctive functional 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.
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 industry. Examples include many sugars (ketoses), many steroids, and the solvent acetone.
In organic chemistry, a vinyl group is a functional group with the formula −CH=CH2. It is the ethylene molecule with one fewer hydrogen atom. The name is also used for any compound containing that group, namely R−CH=CH2 where R is any other group of atoms.
Ethylene glycol is an organic compound with the formula (CH2OH)2. It is mainly used for two purposes: as a raw material in the manufacture of polyester fibers and for antifreeze formulations. It is an odorless, colorless, flammable, viscous liquid. It has a sweet taste, but is toxic in high concentrations. This molecule has been observed in outer space.
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.
Propyne (methylacetylene) is an alkyne with the chemical formula CH3C≡CH. It is a component of MAPD gas—along with its isomer propadiene (allene), which was commonly used in gas welding. Unlike acetylene, propyne can be safely condensed.
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 in a solution. In contrast, heterogeneous catalysis describes processes where the catalysts and substrate are in distinct phases, typically solid and 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.
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).
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.
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).
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.
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 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.