Methacrylate

Methacrylate refers to esters of methacrylic acid or to their salts. The term is most often encountered with methyl methacrylate (MMA), but includes other esters such as ethyl, propyl, and butyl methacrylates, as well as methacrylic acid derivatives such as glycidyl methacrylate. The methacrylate group contains a vinyl double bond adjacent to a methyl-substituted carbonyl, enabling polymerization: CH2=C(CH3)–COOR.

These compounds are mainly used as monomers in free-radical polymerization to form polymethacrylates. The polymerization is typically a chain-growth process initiated by heat, light, or radical initiators. Polymers such as polymethyl methacrylate (PMMA) are transparent and have good weathering resistance, making them widely used in optics and consumer plastics.

Applications of methacrylates span coatings, adhesives, and resins. MMA serves as a major monomer for acrylic resins used in paints, coatings, and adhesives. PMMA is used for optical lenses, acrylic glass, denture bases, bone cement, and dental composites. Methacrylate derivatives such as glycidyl methacrylate are employed as reactive monomers in epoxy systems and for specialty polymers. 3D printing resins and dental materials frequently rely on methacrylate chemistry.

Production and safety: Methacrylates are produced by esterification of methacrylic acid with alcohols or by controlled oxidation of isobutylene to methacrylic acid followed by esterification. Exposure to methacrylate monomers can irritate skin and eyes and may cause sensitization; proper handling, ventilation, and curing are important. Polymeric methacrylates are generally less reactive than their monomer precursors.