polymethylmethacrylate

Polymethyl methacrylate (PMMA) is a transparent thermoplastic polymer derived from the methyl methacrylate monomer (MMA). It is widely known as acrylic glass and marketed under names such as Plexiglas, Lucite, and Perspex. It is clear and rigid.

PMMA is produced by free-radical polymerization of MMA, via bulk, solution, or suspension methods. The polymer offers high optical clarity, excellent light transmission, and low birefringence. Typical refractive index is about 1.49 and the glass transition temperature around 105 °C. Unmodified PMMA can yellow under UV light; UV stabilizers are common in commercial grades.

Mechanical properties include stiffness and good dimensional stability; tensile strength generally 40–80 MPa and a modulus around 2.5–3 GPa. It is harder than many plastics but can be brittle, and its impact resistance is improved with additives or blends.

Common applications include optical components (lenses, screens, skylights, display panels), architectural glazing, automotive and aircraft glazing, aquaria, and lighting diffusers. In medicine, PMMA is used in dental resins, bone cement, and historically for rigid intraocular lenses and some medical devices.

Safety and environment: PMMA is relatively inert in its polymer form, but the monomer MMA is an irritant. PMMA resists water and many chemicals but dissolves in certain solvents such as ketones. End-of-life options include mechanical recycling and energy recovery through incineration.