80°Csourcerecommended max constant operating temperature
Values for
BASF Ultradur B 4300 G6 (PBT, 30% glass fibre), injection moulding grade; product information sheet 09/2026, typical values for uncoloured product at 23 °C.
Celanese GUR 4120 (avg. molecular weight 4.7x10^6 g/mol), typical values on compression-molded specimens; CTE and thermal conductivity from Celanese's generic UHMWPE guide (grade not named)
Every value links to the document that states it. "Not sourced" means no citable source states it (or only a specification minimum); figures computed from it are left out too.
Questions
Is Plastic PBT GF30 stronger than Plastic UHMWPE?
Plastic PBT GF30 is stronger: its tensile strength is 140 MPa against yield strength 20 MPa for Plastic UHMWPE (7x).
Which is lighter, Plastic PBT GF30 or Plastic UHMWPE?
Plastic UHMWPE is lighter: 930 kg/m³ against 1,530 kg/m³ for Plastic PBT GF30.
Which is stiffer, Plastic PBT GF30 or Plastic UHMWPE?
Plastic PBT GF30 is stiffer: Young's modulus 9.8 GPa against 0.66 GPa for Plastic UHMWPE, so the same part in Plastic PBT GF30 deflects less under the same load.
Which is lighter for the same job, Plastic PBT GF30 or Plastic UHMWPE?
For the same stiffness or strength: Plastic PBT GF30 is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate, strong rod or tie, strong beam, strong panel or plate.
Part that must be
Plastic PBT GF30
Plastic UHMWPE
Stiff rod or tie (tension)
lighter
9.03x heavier
Stiff beam (bending)
lighter
2.34x heavier
Stiff panel or plate
lighter
49% heavier
Strong rod or tie
lighter
4.25x heavier
Strong beam
lighter
2.22x heavier
Strong panel or plate
lighter
1.61x heavier
For the same stiffness or strength, mass scales with density over stiffness (or strength) raised to a power set by how the part is loaded: 1 for a rod in tension, 1/2 for a beam in bending, 1/3 for a panel (the standard material-selection indices).
Which conducts heat better, Plastic PBT GF30 or Plastic UHMWPE?
Plastic UHMWPE conducts heat better: 0.4 W/m·K against 0.27 W/m·K for Plastic PBT GF30.
Which expands less with temperature?
Plastic PBT GF30 expands less: 25 µm/m·K against 200 µm/m·K for Plastic UHMWPE.