Ethyl cyanoacrylate (ECA), a cyanoacrylate

ester In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides ar ...

, is an

ethyl Ethyl may refer to: Arts and entertainment * Cold Ethyl, a Swedish rock band *Ethyl Sinclair, a character in the ''Dinosaurs'' television show Science and technology * Ethyl group, an organic chemistry moiety * Ethyl alcohol (or ethanol) * E ...

ester of 2-cyano-

2-propenoic acid 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 ...

. It is a colorless

liquid A liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure. As such, it is one of the four fundamental states of matter (the others being solid, gas, a ...

with low

viscosity The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water. Viscosity quantifies the inte ...

and a faint sweet smell in pure form. It is the main component of cyanoacrylate glues and can be encountered under many

trade name A trade name, trading name, or business name, is a pseudonym used by companies that do not operate under their registered company name. The term for this type of alternative name is a "fictitious" business name. Registering the fictitious name w ...

s. It is soluble in

acetone Acetone (2-propanone or dimethyl ketone), is an organic compound with the formula . It is the simplest and smallest ketone (). It is a colorless, highly volatile and flammable liquid with a characteristic pungent odour. Acetone is miscib ...

, methyl ethyl ketone,

nitromethane Nitromethane, sometimes shortened to simply "nitro", is an organic compound with the chemical formula . It is the simplest organic nitro compound. It is a polar liquid commonly used as a solvent in a variety of industrial applications such as in ...

, and

methylene chloride Dichloromethane (DCM or methylene chloride, methylene bichloride) is an organochlorine compound with the formula . This colorless, volatile liquid with a chloroform-like, sweet odour is widely used as a solvent. Although it is not miscible with ...

. ECA

polymerizes In polymer chemistry, polymerization (American English), or polymerisation (British English), is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. There are many for ...

rapidly in presence of

moisture Moisture is the presence of a liquid, especially water, often in trace amounts. Small amounts of water may be found, for example, in the air (humidity), in foods, and in some commercial products. Moisture also refers to the amount of water vapo ...

Production

Ethyl cyanoacrylate is prepared by the

condensation Condensation is the change of the state of matter from the gas phase into the liquid phase, and is the reverse of vaporization. The word most often refers to the water cycle. It can also be defined as the change in the state of water vapor to ...

formaldehyde Formaldehyde ( , ) (systematic name methanal) is a naturally occurring organic compound with the formula and structure . The pure compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde (refer to section F ...

with ethyl cyanoacetate: : + → + This

exothermic reaction In thermochemistry, an exothermic reaction is a "reaction for which the overall standard enthalpy change Δ''H''⚬ is negative." Exothermic reactions usually release heat. The term is often confused with exergonic reaction, which IUPAC defines ...

affords the polymer, which is subsequently sintered, thermally "cracked" to give the

monomer In chemistry, a monomer ( ; ''mono-'', "one" + '' -mer'', "part") is a molecule that can react together with other monomer molecules to form a larger polymer chain or three-dimensional network in a process called polymerization. Classification Mo ...

. Alternatively, it can be prepared by the ethoxy

carbonylation Carbonylation refers to reactions that introduce carbon monoxide into organic and inorganic substrates. Carbon monoxide is abundantly available and conveniently reactive, so it is widely used as a reactant in industrial chemistry. The term carbon ...

cyanoacetylene Cyanoacetylene is an organic compound with formula or . It is the simplest cyanopolyyne. Cyanoacetylene has been detected by spectroscopy, spectroscopic methods in interstellar clouds, in the Coma (cometary), coma of comet Hale–Bopp and in t ...

Applications

Ethyl cyanoacrylate is used for gluing various materials. It is also used in medicine, for liquid bandages and for suture-less surgery, but it is used less often than the less toxic ''n''-butyl and octyl cyanoacrylates. Off-the-shelf consumer glues are unsuitable for medical applications, as they are not medical-grade, which means their solvent and cyanoacrylate formulations have not been evaluated and optimized to reduce toxicity and prevent foreign body reactions, as would be the case with medical cyanoacrylates In forensics, cyanoacrylate ester has also been found to have excellent non-destructive impressioning abilities, which are especially important when lifting fingerprints from delicate evidence items, or when the prints could not be lifted using traditional means such as fingerprinting powder. The procedure involves heating the acrylate in a sealed chamber. Its fumes then seek out deposited proteins that form into a white, stable, and clear print outlines. The resulting prints could be used as is or enhanced further by staining them with darker pigments. After curing, the resulting resin softens at temperatures above . The service temperature of the joint is . Its

dielectric constant The relative permittivity (in older texts, dielectric constant) is the permittivity of a material expressed as a ratio with the electric permittivity of a vacuum. A dielectric is an insulating material, and the dielectric constant of an insulat ...

at 1

megahertz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or Cycle per second, cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, me ...

is 3.33.

Safety

In the U.S., the threshold limit value for ECA is 0.2 ppm. Heating causes

depolymerization Depolymerization (or depolymerisation) is the process of converting a polymer into a monomer or a mixture of monomers. This process is driven by an increase in entropy. Ceiling temperature The tendency of polymers to depolymerize is indicated by ...

of the cured poly-ECA, producing gaseous products which are a strong irritant to the

lung The lungs are the primary organs of the respiratory system in humans and most other animals, including some snails and a small number of fish. In mammals and most other vertebrates, two lungs are located near the backbone on either side of t ...

s and eyes.

References

{{reflist Ethyl esters Monomers Cyanoacrylate esters Lachrymatory agents Sweet-smelling chemicals

Production

Applications

Safety

See also

References