What is PBT?

Polybutylene Terephthalate (PBT) is a semi-crystalline thermoplastic that belongs to the polyester family of polymers. It has several different grades that will allow for reinforcement, filled, impact modification, and flame retardancy. It has excellent mechanical and electrical characteristics, it’s stain-resistant, light, and has exceptional short-term mechanical properties.  With high dielectric strength PBT protects electrical and electronic components. It is highly resistant and guards against leakage and breakdown in power circuitry.

Polybutylene Terephthalate (PBT) Part – Agriculture
Benefits

Stain-resistant
Lightweight
Excellent short-term mechanical properties
Can last short term thermal excursions and long-term heat exposure
High dielectric strength
Block UV radiation, excellent heat aging behavior
Chemical resistance
Drawbacks

High mold shrinkage
Poor resistance to hydrolysis (sensitive to hot water)
Prone to warping
Unreinforced PBT is notch sensitive
Low HDT at 60° degree Celsius (140° Fahrenheit)

PBT Polyester (Polybutylene Terepthalate)
– Consumer Products
How can I use it?

Industrial

Common applications for the industrial market include electrical, electrical components, windshield wiper covers, mirror housings, cowl vents.

Properties of PBT
The polymer displays excellent mechanical and electrical properties. Review the key properties of this polyester material discussed below.

It has excellent stain resistance and machining characteristics
It enables efficient use of material to reduce weight and cost
It delivers excellent short-term mechanical properties, such as high strength, toughness and stiffness as well as good practical impact
It provides good creep resistance, dimensional stability and low moisture absorption characteristics
Elongation at Break    5-300%
Elongation at Yield    3.5-9%
Flexibility (Flexural Modulus)    2-4 GPa
Hardness Rockwell M    70-90
Hardness Shore D    90-95
Stiffness (Flexural Modulus)    2-4 GPa
Strength at Break (Tensile)    40-50 MPa
Toughness (Notched Izod Impact at Room Temperature)    27-999 J/m
Toughness at Low Temperature (Notched Izod Impact at Low Temperature)    27-120 J/m
Young’s Modulus    2-3 GPa
Coefficient of Linear Thermal Expansion    6-10 x 10-5 /°C
Shrinkage    0.5-2.2%
Water Absorption 24 hours    0.1-0.2%