PHB (polyhydroxybutyrate, a PHA)

A microbially-produced, renewable and marine-biodegradable polyester; stiffness and barrier close to polypropylene but brittle, and it embrittles further on ageing as it slowly crystallises. The best-known polyhydroxyalkanoate (PHA).

← All materials
PropertyValueSourceMethodConditionsNote
Density1.25 g/cm³Sudesh, Abe & Doi, Prog. Polym. Sci. 25 (2000) 1503–1555 — PHA structure & properties review23 °C, dry
Young's modulus E3.5 GPaSudesh, Abe & Doi, Prog. Polym. Sci. 25 (2000) 1503–1555 — PHA structure & properties review23 °C, dryhigh-crystallinity; secondary crystallisation on ageing lowers it toward ~1.7
Tensile strength40 MPaSudesh, Abe & Doi, Prog. Polym. Sci. 25 (2000) 1503–1555 — PHA structure & properties review23 °C, drybrittle — elongation ~5%
Glass transition Tg4 °CSudesh, Abe & Doi, Prog. Polym. Sci. 25 (2000) 1503–1555 — PHA structure & properties reviewDSC23 °C, drynear room temperature
Melting point Tm177 °CSudesh, Abe & Doi, Prog. Polym. Sci. 25 (2000) 1503–1555 — PHA structure & properties reviewDSC23 °C, dry
  • 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. Always confirm against the supplier datasheet before design work. Data policy: docs/DATA-SOURCES.md in the repository.