Methacrylate refers to derivatives of methacrylic acid. These derivatives include the parent acid (CH2CCO2H), salts (e.g. , CH2CCO2Na), esters (e.g. CH2CCO2CH3, or methyl methacrylate) and the polymers of these species. Methacrylates are common monomers in polymer plastics, forming the acrylate polymers. Methacrylates easily form polymers because the double bonds are very reactive.