Properties of Polybutylene (PB)
Polybutylene is a type of plastic polymer that was commonly used in the manufacture of water supply piping and plumbing systems from the late 1970s to the mid-1990s. It was known for its flexibility and low cost, but it became notorious for its tendency to degrade and fail prematurely, leading to leaks and water damage in many homes.
The following table provides a comprehensive list of polybutylene (PB) properties in both SI and US customary/Imperial units at normal temperature and pressure (NTP).
Click on the icon to switch between Metric and Imperial units.
| Physical Properties | Metric |
|---|---|
| Category | Thermoplastic |
| Density | 935 kg/m3 |
| Water Absorption | 0.03 %wt/day |
| Mechanical Properties | Metric |
| Yield Tensile Strength | 16 - 18 MPa |
| Young’s Modulus (E) | 0.3 GPa |
| Flexural Modulus | 0.75 GPa |
| Shore Hardness (D) | 60 |
| Thermal Properties | Metric |
| Melting Point | 127 °C |
| Thermal Conductivity | 0.22 W/m·K |
| Coefficient of Thermal Expansion (αL) | 1.3×10-5 1/°C |
| Vicat Softening Temperature | 113 °C |
| Electrical Properties | Metric |
| Relative Permittivity (@1 MHz) (εr) | 2.53 |
Unless stated otherwise, all values are taken at room temperature (approximately 20°C or 68°F) and 1 atm pressure. (1 atm = 101,325 Pa)
Related Pages
References: 1) Cardarelli, François. Materials Handbook: A Concise Desktop Reference. Switzerland: Springer International Publishing, 2018. 2) CRC Handbook of Chemistry and Physics, 97th Edition. United Kingdom: CRC Press, 2016-2017. 3) A.M. Howatson, P.G. Lun, J.D. Todd, P.D. Engineering Tables and Data. United Kingdom: University of Oxford, Department of Engineering Science, 2009.