Polymethyl methacrylate PMMA -Economic aspects

Polymethyl methacrylate, PMMA, is derived from the polymerization of methyl methacrylate, MMA.

Acrylic acid was discovered in 1843. Methacrylic acid, a derivative of acrylic acid, was formulated in 1865. In 1877, German chemists Fittig and Paul discovered the polymerization process that transforms methyl methacrylate into polymethyl methacrylate. In 1933, German chemist Otto Röhm patented the Plexiglas trademark and launched the first commercial production run. At the same time, ICI launched PMMA in cast sheet form. During the Second World War, acrylic glass was used for submarine periscopes, windscreens, canopies and aircraft turrets.

PMMA is polymerized using three conventional processes: casting, suspension and bulk. Casting polymerization produces thick, perfectly-surfaced sheets between two glass plates. The other two processes, suspension and mass, produce granules and extruded sheets.

PMMA is an essentially amorphous plastic. Without the addition of inhibitors, the monomer is highly unstable. The action of heat, oxygen, UV rays or the addition of a peroxide is sufficient to trigger polymerization. This property is used for plate casting, among other applications.