2-methylprop-2-enoic acid; α-Methacrylic Acid; 2-Methyl-2-propenoic Acid; Methacrylic Acid; 2-Methyl-2-propenoate; 2-Methyl-2-propenoic Acid;2-Methylacrylic Acid; Isobutenic Acid; Light Ester A