Acrylic acid is H2C=CH-COOH and methacrylic acid is H2C=C(CH3)COOH. These compounds and their methyl esters are both quite reactive and difficult to store and handle. The monomer used to form poly(methyl methacrylate), 2-hydroxy-2-methylpropanenitrile, is prepared by the following reaction:
2-Hydroxy-2-methylpropanenitrile is then reacted with methanol (or other alcohol) to yield methacrylate ester. Free-radical polymerization is initiated by peroxide or azo catalysts and produce poly(methyl methacrylate) resins having the following formula:
Key properties are good resistance to heat, light, and weathering. This polymer is unaffected by most detergents, cleaning agents, and solutions of inorganic acids, alkalies, and aliphatic hydrocarbons. Poly(methyl methacrylate) has light transmittance of 92% with a haze of 1–3% and its clarity is equal to glass.