Ethyl cyanoacrylate

Ethyl cyanoacrylate (ECA), a cyanoacrylate ester, is an ethyl ester of 2-cyano-2-propenoic acid. It is a colorless liquid with low viscosity and a faint sweet smell in pure form. It is the main component of cyanoacrylate glues and can be encountered under many trade names. It is soluble in acetone, methyl ethyl ketone, nitromethane, and methylene chloride. ECA polymerizes rapidly in presence of moisture. CH 2 ( C ≡ N ) CO 2 Et + CH 2 O ⟶ CH 2 = C ( C ≡ N ) CO 2 Et + H 2 O {displaystyle {ce {CH2 (C#N) CO2 Et + CH2O -> CH2=C (C#N) CO2 Et + H2O}}} Ethyl cyanoacrylate (ECA), a cyanoacrylate ester, is an ethyl ester of 2-cyano-2-propenoic acid. It is a colorless liquid with low viscosity and a faint sweet smell in pure form. It is the main component of cyanoacrylate glues and can be encountered under many trade names. It is soluble in acetone, methyl ethyl ketone, nitromethane, and methylene chloride. ECA polymerizes rapidly in presence of moisture. Ethyl cyanoacrylate is prepared by the condensation of formaldehyde with ethyl cyanoacetate: This exothermic reaction affords the polymer, which is subsequently sintered, thermally 'cracked' to give the monomer. Alternatively, it can be prepared by the ethoxycarbonylation of cyanoacetylene. 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 After curing, the resulting resin softens at temperatures above 150 °C (302 °F). The service temperature of the joint is −54–82 °C (−65–180 °F). Its dielectric constant at 1 megahertz is 3.33. In the U.S., the Threshold Limit Value for ECA is 0.2 ppm. Heating causes depolymerization of the cured poly-ECA, producing gaseous products which are a strong irritant to the lungs and eyes.