PMMA (Polymethyl Methacrylate)

PMMA (polymethyl methacrylate) is a transparent thermoplastic. Developed initially in 1928, it is a synthetic polymer of methyl methacrylate and is often used as a light-resistant or shatter-resistant alternative to glass. You are most likely familiar with this chemical compound by the trademark name "Plexiglas," but it also has a variety of other applications.

Uses of PMMA

PMMA serves a variety of functions due to its easy handling and processing and relatively low cost. It can be brittle under heavy impact force, and is more prone to scratching than regular glass, but is used in a number of different ways, including:

• Transparent glass substitute – PMMA is commonly used in aquariums, exterior light lenses on automobiles, motorcycle helmet visors, glass replacement in riot control vehicles, viewing ports in submersible vehicles, aircraft windows, certain lighthouse lenses, and more.
• Daylight redirection – PMMA can be used in laser-cut panels to redirect sunlight into a light pipe and then spread it into a room. It can also be used for "daylighting," in which a specialized window or canopy directs sunlight to the ceiling or into a room, rather than to the floor, for increased illumination.
• Artistic and aesthetic purposes – PMMA is used in acrylic paint, furniture, picture framing, sculpting, jewelry, and more.

Medical Applications of PMMA

Since it has a good degree of compatibility with human tissue, PMMA is often used for the replacement of intraocular lenses in the eye, such as in a treatment for cataracts. It is also commonly used to make dentures, dental filling materials, and as a wrinkle- or scar-reducing compound in cosmetic surgeries. In orthopedic surgery, PMMA is often used in a compound to make bone cement, used to affix implants and remodel lost bone. A special mixture containing PMMA creates a dough-like cement that gradually hardens. It is often used to fill the space between bone and a prosthesis to prevent movement.