How thermally stable is Acrylic or Plexiglas (PMMA)
To ensure component stability, it is important to heat treat both the base material and finished component to ensure that they are stress free and will remain stable over a long period of time.
Carville produce precision machined components in acrylic and other engineering plastic for medical and industrial applications. It is important to remember that we are discussing plastics and should always apply realistic working tolerances.
Acrylic has a coefficient of thermal expansion at 7.7 x 10-5. It is possible to produce a 100mm diameter component to a tolerance of +/- 0.1mm, however, a change in ambient temperature of 15⁰C would take this component out of limits.
Consideration should be given to working tolerances and the end application when selecting the correct plastic materials and considering the use of plastic components.