Cyanoacrylat

Cyanoacrylat, commonly referred to as cyanoacrylate, denotes a family of fast-acting acrylate adhesives. They are esters of cyanoacrylic acid with various alkyl groups, most often methyl, ethyl, butyl, isobutyl, or octyl. The general structural formula is CH2=C(CN)-COOR, where R represents the alkyl substituent. These monomers rapidly polymerize to form polycyanoacrylates, which bond strongly to a wide range of substrates including plastics, metals, ceramics, and biological tissues.

Curing and mechanism: The polymerization is anionic and is initiated by trace moisture or nucleophiles on surfaces. The presence of water on the substrate or in the adhesive creates a rapid curing process, causing the material to harden and form a cohesive bond. Cure occurs quickly from the surface inward and can generate heat as the polymer chains grow.

Variants and applications: Industrial cyanoacrylates (such as methyl, ethyl, isobutyl, and octyl cyanoacrylates) are widely used as instant glues in manufacturing and household products. Medical-grade formulations use longer-chain esters (for example butyl or 2-octyl cyanoacrylate) and are designed for biocompatibility; they are employed in wound closure, tissue sealing, and some surgical procedures. Other applications include dentistry, electronics, and hobbyist fixing.

Safety and handling: Cyanoacrylates bond skin and tissues rapidly and should be used with caution. Vapors can irritate the eyes and respiratory tract; use in well-ventilated areas and avoid contact with skin. Thick layers or exothermic curing can pose safety concerns. Storage requires cool, dry, tightly closed containers with stabilizers to prevent premature polymerization. Regulatory status varies by country and formulation, particularly for medical products.