Polished acrylic components comprise most of the optically clear parts in use today. In its uncolored grade, acrylic has clarity equivalent to glass but is lighter in weight, more rigid, and more resistant to scratches and breakage. It is one of the least expensive materials for optically clear parts, and it features a tint-free finish. Acrylic is a versatile alternative to both glass and heavier plastics, easily withstanding dramatic temperature changes.
ACRYLIC AT A GLANCE
- Lowest cost
- Excellent light transmission – 92%
- UV stable
- Low continuous service temperature to 150°F
- Relatively brittle
- Reasonably hard; does not scratch easily
- Low chemical resistance; nothing stronger than Isopropanol may be used
- Great for pneumatics
- Easy to bond
Acrylic is the most frequently used materials for bonded device manifolds, due to its low cost and excellent clarity. It allows for full inspection of all channels and passages in components, and it can easily be machined and bonded into components and assemblies.
More about Acrylic
Acrylic is the closest plastic substitute for window glass. General purpose-grade cast and polished acrylic parts will block UV wavelengths up to 360 NM (for applications requiring transmittance of 280 NM and above, consider UVT grade). Total internal reflection is possible in acrylic parts, making them useful in light pipe applications.
Acrylic has good weathering ability, high impact resistance, and good chemical resistance and dimensional stability. A skilled machinist can make drilled holes in acrylic straight and clear. Buffing, flame polishing, and optical machining are all effective polishing processes for acrylic. The polishing of acrylic allows for many novel edge lighting approaches, and highly polished acrylic lenses are often produced by optical machining.
Acrylic performs well in pneumatic and vacuum applications. Operating pressures as high as 150 psi (depending on channel layout) can be supported.
Acrylic's General Engineering Characteristics
- Coefficient of Thermal Stability – 0.00004 in/in/°F
- High dielectric constant
- Light transmission: 92%
- Haze: 1% UV stable
- Continues service temperature to 175°F, bursts to 200°F
- Tensile strength 10,500 psi
- Modulus of elasticity – 450,000 psi (tensile)
- Flammability: 94HB
- Available in many different colors