Twenty Kinds of Plastics and Their Properties—(14) PMMA

14.PMMA polymethyl methacrylate

Typical application range:

Automotive industry (signal lamp equipment, dashboard, etc.), pharmaceutical industry (blood storage container, etc.), industrial applications (video disc, light diffuser), daily consumer goods (beverage cups, stationery, etc.).

Injection molding process conditions:

Drying process: PMMA has a hygroscopic property, so it is necessary to dry before processing. It is suggested that the drying condition is 90 °C and 2~4 hours.
Melting temperature: 240~270 °C.
Mold temperature: 35~70 °C.
Injection speed: medium

Chemical and physical properties:

1. PMMA has the optical properties and weatherability of fine, white light transmittance is as high as 92%.
2. PMMA products have very low birefringence, especially suitable for making DVDs and so on.
3. PMMA has the properties of room temperature creep. With the increase of load and time, the phenomenon of stress cracking can be caused.
4. PMMA has good impact resistance.