Plastic LCP GF30 vs. Plastic PBT GF30

Compare Plastic LCP GF30 vs. Plastic PBT GF30 strength, stiffness, weight and thermal properties.

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Plastic LCP GF30Bulk polymer (molded or machined)

Plastic PBT GF30Bulk polymer (molded or machined)

Mechanical
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Yield strength	not given (tensile used)	not given (tensile used)
Ultimate tensile strength	115MPasourcetensile strength (ISO 527)	140MPasourcestress at break, 23 °C
Flexural strength	184MPasourcetypical (ISO 178)	210MPasourcetypical, 23 °C
Elongation at break	1.5%sourcetensile elongation (ISO 527)	3%sourcestrain at break, 23 °C
Young's modulus (stiffness)	11.5GPasourcetensile modulus (ISO 527)	9.8GPasourcetypical, 23 °C
Density	1,610kg/m³sourcetypical	1,530kg/m³sourcetypical
Strength to weight	71.4kN·m/kg	91.5kN·m/kg28% higher
Stiffness to weight	7.14MN·m/kg12% higher	6.41MN·m/kg
Poisson's ratio	not sourced	not sourced
Shear modulus	not sourced	not sourced
Bulk modulus	not sourced	not sourced
Speed of sound	2,673m/s	2,531m/s
Thermal
Thermal conductivity	0.5W/m·Ksourcehot disk (ISO 22007-2), temperature not stated	0.27W/m·Ksourcetypical (DIN 52612-1)
Thermal expansion	20µm/m·Ksourceflow direction (MD), mean 50-150 °C	25µm/m·Ksourcelongitudinal (flow), mean 23-55 °C
100 mm part over a 50 °C swing	100µm growth25% less	125µm growth
Specific heat	839J/kg·KsourceASTM E1269, temperature not stated	1,050J/kg·Ksourcetypical, 23 °C
Heats up and cools (diffusivity)	0.37mm²/s2.2x faster	0.168mm²/s
Thermal shock resistance	not sourced	not sourced
Melting point	not sourced	223°CsourceDSC (ISO 11357)
Max service temperature	288°CsourceHDT 1.8 MPa (ISO 75)	205°CsourceHDT 1.8 MPa
Values for	Sumitomo Chemical SUMIKASUPER LCP E6006L (30% glass fibre; high strength, low shrinkage); SUMIKASUPER LCP Technical Note, Version 04 / Nov. 2023, typical values.	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.

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 LCP GF30 stronger than Plastic PBT GF30?

Plastic PBT GF30 is stronger: its tensile strength is 140 MPa against 115 MPa for Plastic LCP GF30 (22%).

Which is lighter, Plastic LCP GF30 or Plastic PBT GF30?

Plastic PBT GF30 is lighter: 1,530 kg/m³ against 1,610 kg/m³ for Plastic LCP GF30.

Which is stiffer, Plastic LCP GF30 or Plastic PBT GF30?

Plastic LCP GF30 is stiffer: Young's modulus 11.5 GPa against 9.8 GPa for Plastic PBT GF30, so the same part in Plastic LCP GF30 deflects less under the same load.

Which is lighter for the same job, Plastic LCP GF30 or Plastic PBT GF30?

For the same stiffness or strength: Plastic LCP GF30 is lighter for a stiff rod or tie (tension), stiff beam (bending); Plastic PBT GF30 is lighter for a strong rod or tie, strong beam, strong panel or plate.

Part that must be	Plastic LCP GF30	Plastic PBT GF30
Stiff rod or tie (tension)	lighter	12% heavier
Stiff beam (bending)	lighter	3% heavier
Stiff panel or plate	about equal	about equal
Strong rod or tie	28% heavier	lighter
Strong beam	20% heavier	lighter
Strong panel or plate	16% heavier	lighter

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 LCP GF30 or Plastic PBT GF30?

Plastic LCP GF30 conducts heat better: 0.5 W/m·K against 0.27 W/m·K for Plastic PBT GF30.

Which expands less with temperature?

Plastic LCP GF30 expands less: 20 µm/m·K against 25 µm/m·K for Plastic PBT GF30.

Among 72 materials

Stiffness against density

Strength against density