Thermoplastic comparison
PBT (polybutylene terephthalate) vs Acrylic (PMMA)
Every value below is a typical room-temperature figure with its source, test method and conditions — the same dataset that drives the calculators.
| Property | PBT (polybutylene terephthalate) | Acrylic (PMMA) | Difference |
|---|---|---|---|
| Density | 1.31 g/cm³ | 1.19 g/cm³ | PBT (polybutylene terephthalate) — 10% higher |
| Young's modulus E | 2.6 GPa | 3.1 GPa | Acrylic (PMMA) — 19% higher |
| Tensile strength | 55 MPa | 72 MPa | Acrylic (PMMA) — 31% higher |
| Glass transition Tg | 45 °C | 105 °C | Acrylic (PMMA) — 60 °C higher |
Where these numbers come from
- CAMPUS plastics database — typical grade datasheet values (campusplastics.com)
- Callister & Rethwisch, Materials Science and Engineering, 10th ed.
Typical room-temperature values for learning and preliminary design; grades vary widely and a supplier datasheet always overrides a textbook figure. Confirm against the datasheet before design work.