Thermoplastic comparison
PBT (polybutylene terephthalate) 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 | PBT (polybutylene terephthalate) | PHB (polyhydroxybutyrate, a PHA) | Difference |
|---|---|---|---|
| Density | 1.31 g/cm³ | 1.25 g/cm³ | PBT (polybutylene terephthalate) — 5% higher |
| Young's modulus E | 2.6 GPa | 3.5 GPa | PHB (polyhydroxybutyrate, a PHA) — 35% higher |
| Tensile strength | 55 MPa | 40 MPa | PBT (polybutylene terephthalate) — 38% higher |
| Glass transition Tg | 45 °C | 4 °C | PBT (polybutylene terephthalate) — 41 °C higher |
| Melting point Tm | 225 °C | 177 °C | PBT (polybutylene terephthalate) — 48 °C higher |
Where these numbers come from
- CAMPUS plastics database — typical grade datasheet values (campusplastics.com)
- 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.