Thermoplastic comparison
PETG (glycol-modified PET) vs PHB (polyhydroxybutyrate, a PHA)
Every value below is a typical room-temperature figure with its source, test method and conditions — the same dataset that drives the calculators.
| Property | PETG (glycol-modified PET) | PHB (polyhydroxybutyrate, a PHA) | Difference |
|---|---|---|---|
| Density | 1.3 g/cm³ | 1.25 g/cm³ | PETG (glycol-modified PET) — 4% higher |
| Young's modulus E | 2.2 GPa | 3.5 GPa | PHB (polyhydroxybutyrate, a PHA) — 59% higher |
| Tensile strength | 53 MPa | 40 MPa | PETG (glycol-modified PET) — 32% higher |
| Glass transition Tg | 81 °C | 4 °C | PETG (glycol-modified PET) — 77 °C higher |
Where these numbers come from
- MakeItFrom.com materials database — typical grade values
- Sudesh, Abe & Doi, Prog. Polym. Sci. 25 (2000) 1503–1555 — PHA structure & properties review
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.