PHB (polyhydroxybutyrate, a PHA) vs Polystyrene (GPPS)

Every value below is a typical room-temperature figure with its source, test method and conditions — the same dataset that drives the calculators.

PHB (polyhydroxybutyrate, a PHA) in fullPolystyrene (GPPS) in full← All materials
PropertyPHB (polyhydroxybutyrate, a PHA)Polystyrene (GPPS)Difference
Density1.25 g/cm³1.05 g/cm³PHB (polyhydroxybutyrate, a PHA) — 19% higher
Young's modulus E3.5 GPa3.2 GPaPHB (polyhydroxybutyrate, a PHA) — 9% higher
Tensile strength40 MPa46 MPaPolystyrene (GPPS) — 15% higher
Glass transition Tg4 °C100 °CPolystyrene (GPPS) — 96 °C higher
  • Sudesh, Abe & Doi, Prog. Polym. Sci. 25 (2000) 1503–1555 — PHA structure & properties review
  • 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.