Plexiglass

Plexiglass is the trade name for polymethyl methacrylate (PMMA), a transparent thermoplastic polymer also known as acrylic glass, acrylic, or PMMA. It is widely used as a clear, shatter-resistant alternative to glass in a variety of applications.

PMMA combines high optical clarity with good weather resistance and light weight, typically about half the weight of glass. It offers strong light transmission and can be heat-formed for complex shapes. It has a glass transition around 105°C, after which it softens. While it is more impact resistant than glass, it can still crack under severe load and is more prone to scratching, though scratch-resistant coatings are available. PMMA is resistant to many chemicals but can be attacked by certain solvents such as acetone and ketones. UV-stabilized grades help prevent yellowing with prolonged exposure.

Two main production methods exist: cast PMMA and extruded PMMA. Cast PMMA generally provides higher optical quality and lower internal stress, while extruded PMMA is more affordable and uniform in thickness. PMMA sheets are available in clear, tinted, frosted, or patterned forms and can be drilled, cut, and machined. Protective film is often applied to protect surfaces during fabrication.

Common applications include architectural glazing, skylights, signs, display cases, protective barriers, automotive and aircraft components, aquariums, lenses, and medical devices. PMMA is recyclable, though it is typically handled separately from glass in recycling streams.