Plastic HDPE vs. Plastic LCP GF30

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

Plastic HDPEBulk polymer (molded or machined)

Plastic LCP GF30Bulk polymer (molded or machined)

Mechanical	Plastic HDPE	Plastic LCP GF30
Yield strength	24MPa1	not given (tensile used)
Ultimate tensile strength	not stated (yield given)	tensile strength115MPa2
Flexural strength	not sourced	184MPa2
Elongation at break	not sourced	tensile elongation1.5%2
Young's modulus (stiffness)	0.9GPa1	tensile modulus11.5GPa212.8x stiffer
Density	950kg/m³11.69x lighter	1,610kg/m³2
Strength to weight	25.3kN·m/kg	71.4kN·m/kg2.83x higher
Stiffness to weight	0.947MN·m/kg	7.14MN·m/kg7.54x higher
Poisson's ratio	base material0.4–0.453	not sourced
Shear modulus	0.316GPa	not sourced
Bulk modulus	2GPa	not sourced
Speed of sound	973m/s	2,673m/s2.75x faster

Stiffness against densityHigher and further left: stiffer for its weight

Strength against densityHigher and further left: stronger for its weight

Thermal	Plastic HDPE	Plastic LCP GF30
Thermal conductivity	base material0.4–0.49W/m·K3	hot disk0.5W/m·K2
Thermal expansion	base material120µm/m·K3	flow direction20µm/m·K26x less
100 mm part over a 50 °C swing	600µm growth	100µm growth6x less
Specific heat	base material2,250J/kg·K32.68x higher	ASTM E1269839J/kg·K2
Heats up and cools (diffusivity)	0.208mm²/s	0.37mm²/s1.78x faster
Thermal shock resistance	56.9W/m	not sourced
Max service temperature	not sourced	HDT 1.8 MPa288°C2

Thermal conductivity against densityHigher and further left: spreads more heat for its weight

Thermal expansion against thermal conductivityLower and further right: warps less when heated

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Sources3 documents: LyondellBasell, Sumitomo Chemical, INEOS Olefins & Polymers USA

Plastic HDPE: LyondellBasell Hostalen 23050 B high density polyethylene, typical ISO values
Plastic LCP GF30: Sumitomo Chemical SUMIKASUPER LCP E6006L (30% glass fibre; high strength, low shrinkage); SUMIKASUPER LCP Technical Note, Version 04 / Nov. 2023, typical values.

1
Hostalen 23050 B Product DataLyondellBasellPlastic HDPE · Yield strength: typical, tensile stress at yield 23 °C, 50 mm/min ISO 527Plastic HDPE · Young's modulus (stiffness): typical, tensile modulus 23 °C ISO 527Plastic HDPE · Density: typical, ISO 1183
2
SUMIKASUPER LCP Technical Note, Version 04 (2023)Sumitomo Chemicalarchived copyPlastic LCP GF30 · Ultimate tensile strength: tensile strength (ISO 527)Plastic LCP GF30 · Flexural strength: typical (ISO 178)Plastic LCP GF30 · Elongation at break: tensile elongation (ISO 527)Plastic LCP GF30 · Young's modulus (stiffness): tensile modulus (ISO 527)Plastic LCP GF30 · Density: typicalPlastic LCP GF30 · Thermal conductivity: hot disk (ISO 22007-2), temperature not statedPlastic LCP GF30 · Thermal expansion: flow direction (MD), mean 50-150 °CPlastic LCP GF30 · Specific heat: ASTM E1269, temperature not statedPlastic LCP GF30 · Max service temperature: HDT 1.8 MPa (ISO 75)
3
Typical Engineering Properties of High Density PolyethyleneINEOS Olefins & Polymers USAarchived copyPlastic HDPE · Poisson's ratio: base material: high-density polyethylene family (INEOS Olefins & Polymers USA, Typical Engineering Properties of HDPE)Plastic HDPE · Thermal conductivity: base material: high-density polyethylene family (INEOS Olefins & Polymers USA, Typical Engineering Properties of HDPE)Plastic HDPE · Thermal expansion: base material: high-density polyethylene family (INEOS Olefins & Polymers USA, Typical Engineering Properties of HDPE)Plastic HDPE · Specific heat: base material: high-density polyethylene family (INEOS Olefins & Polymers USA, Typical Engineering Properties of HDPE)

Each number points to the document that states it, with the exact basis. Values without a number are computed from the sourced ones. "Not sourced" means no citable source states it (or only a specification minimum); figures computed from it are left out too.

Questions

Mechanical

Is Plastic HDPE stronger than Plastic LCP GF30?

Plastic LCP GF30 is stronger: its tensile strength is 115 MPa against yield strength 24 MPa for Plastic HDPE (4.79x).

Which is lighter, Plastic HDPE or Plastic LCP GF30?

Plastic HDPE is lighter: 950 kg/m³ against 1,610 kg/m³ for Plastic LCP GF30.

Which is stiffer, Plastic HDPE or Plastic LCP GF30?

Plastic LCP GF30 is stiffer: Young's modulus 11.5 GPa against 0.9 GPa for Plastic HDPE, so the same part in Plastic LCP GF30 deflects less under the same load.

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

For the same stiffness or strength: Plastic LCP 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 HDPE	Plastic LCP GF30
Stiff rod or tie (tension)	7.54x heavier	lighter
Stiff beam (bending)	2.11x heavier	lighter
Stiff panel or plate	38% heavier	lighter
Strong rod or tie	2.83x heavier	lighter
Strong beam	1.68x heavier	lighter
Strong panel or plate	29% 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).

Thermal

Which conducts heat better, Plastic HDPE or Plastic LCP GF30?

Plastic LCP GF30 conducts heat better: 0.5 W/m·K against 0.445 W/m·K for Plastic HDPE.

Which expands less with temperature?

Plastic LCP GF30 expands less: 20 µm/m·K against 120 µm/m·K for Plastic HDPE.