Acrylics have outstanding resistance to long-term exposure to sunlight and weathering. Polymethyl methacrylate (PMMA), a hard, rigid, and transparent plastic, is the most widely used member of the acrylic family. Cast PMMA sheet has excellent optical properties (it transmits about 92% total light) and is more resistant to impact than glass. In addition to excellent optical properties, acrylics have low water absorption, good electrical resistivity, and fair tensile strength. Acrylic plastics are available as compounds for extrusion, injection molding, blow molding, and casting. Extruded or cast sheet and film also are marketed.

Applications: Include outdoor signs, glazing, aircraft canopies, skylights, auto tail-lights, dials, buttons, lighting applications, knobs, and machine covers.