Cyanoacrylates are a family of strong fast-acting adhesives with industrial, medical, and household uses. They are various esters of cyanoacrylic acid. The acryl groups in the resin rapidly polymerises in the presence of water to form long, strong chains. They have some minor toxicity.
Specific cyanoacrylates include methyl 2-cyanoacrylate (MCA), ethyl 2-cyanoacrylate (ECA, commonly sold under trade names such as "Super Glue" and "Krazy Glue", or Toagosei), n-butyl cyanoacrylate (n-BCA), octyl cyanoacrylate and 2-octyl cyanoacrylate (used in medical, veterinary and first aid applications). Octyl cyanoacrylate was developed to address toxicity concerns and to reduce skin irritation and allergic response. Cyanoacrylate adhesives are sometimes known generically as instant glues, power glues or superglues. The abbreviation "CA" is commonly used for industrial grade cyanoacrylate.