Acrylic is also known as PMMA (Poly methyl methacrylate) acrylic glass, Plexiglas, Lucite, Crylux, Perclax and Perspex. It is a synthetic polymer and an engineering plastic. It is used in sheet form and is lightweight and shatter-resistant.
Acrylic is a versatile material and is used in a wide range of fields and applications. It is used in the rear lights of vehicles, appliances, lenses for glasses and more. In sheet form, it is used for building shatter-resistant windows, skylights, bulletproof security barriers, signs and displays, LCD screens and more.
Unique properties of acrylic
- Acrylic has a refractive index of 1.49 and transmits up to 92% of visible light. It can be easily heat-formed without losing optical clarity. The mechanical and optical properties of acrylic do not get affected even when it is exposed to moisture for a prolonged period.
- Acrylic swells and dissolves in many organic solvents. It has poor resistance to other chemicals. However, its environmental stability is superior to other plastics and is therefore used in outdoor applications. It is not attacked by many foods and food is not affected by it.
- It is more impact resistant than glass and when it has to go through impact beyond the limitations it breaks into comparatively larger pieces. It is tough and resilient.
- It is weather resistant and does not get affected by extreme cold, blazing sun, salt water spray and more. It will not shrink and its colour will not change.
- Translucent white Acrylic has excellent light-diffusing properties. It is a preferred plastic for all types of lighting fixtures and signs. It can be obtained in different densities with a light transmittance of 11% – 67%. PMMA is available in transparent and translucent colours.
- It is a good insulator and its surface resistivity is much higher than that of other plastics. Continuous outdoor exposure has less effect on its electrical properties.
- All plastics expand and contract at a much faster rate than metals or glass. Acrylic can be used for outdoor applications and acrylic sheets will expand during the summer and contract during the winter. For outdoor glazing, the sheet must be cut shorter to the frame size.
- Acrylic is not rigid like metals or glass. Under load like wind load, it will bow and foreshorten as a result of deflection. Therefore the channels that engage the edges of the Acrylic sheet should have sufficient depth. Acrylic is more rigid than other plastics.
- It has a good tensile strength, but stress-crazing can occur due to load. Therefore, stress must be avoided and it is better to install Acrylic in frames rather than fasten large sheets with bolts.
It should not be exposed to high heat sources like high-wattage incandescent lamps. It ignites at 460° C temperature and burns.
Naren Patel 