Plastic ABS (bulk/injection) vs. Rubber

Compare Plastic ABS (bulk/injection) vs. Rubber strength, stiffness, weight and thermal properties.

Plastic ABS (bulk/injection)Bulk polymer (molded or machined)

RubberBulk polymer (molded or machined)

Mechanical	Plastic ABS (bulk/injection)	Rubber
Yield strength	45MPa1	not given (tensile used)
Ultimate tensile strength	not stated (yield given)	23MPa2
Flexural strength	65MPa1	not sourced
Elongation at break	10%1	830%283x more ductile
Young's modulus (stiffness)	2.3GPa1	not sourced
Density	1,040kg/m³1	960kg/m³2
Strength to weight	43.3kN·m/kg1.81x higher	24kN·m/kg
Stiffness to weight	2.21MN·m/kg	not sourced
Poisson's ratio	0.393	government0.54
Shear modulus	0.827GPa	not sourced
Bulk modulus	3.48GPa	not sourced
Speed of sound	1,487m/s	not sourced

Stiffness against densityHigher and further left: stiffer for its weight

Strength against densityHigher and further left: stronger for its weight

Thermal	Plastic ABS (bulk/injection)	Rubber
Thermal conductivity	0.17W/m·K113% more heat through a fin	0.151W/m·K5
Thermal expansion	range80–110µm/m·K1	not sourced
100 mm part over a 50 °C swing	475µm growth	not sourced
Specific heat	not sourced	government1,881J/kg·K4
Heats up and cools (diffusivity)	not sourced	0.0836mm²/s
Thermal shock resistance	21.4W/m	not sourced
Max service temperature	HDT 1.8 MPa94°C1	70°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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Sources5 documents: INEOS Styrolution, Weir Minerals, Covestro, National Institute of Standards and Technology, Defense Technical Information Center

Plastic ABS (bulk/injection): INEOS Styrolution Terluran GP-22 general-purpose injection-molding ABS, ISO typical values (TDS revision 08/01/2022)
Rubber: Weir Minerals Linatex Premium rubber (95 % natural rubber), typical physical properties, spec sheet WMD0118/202305

1
Terluran GP-22 (ABS) Product Data SheetINEOS StyrolutionPlastic ABS (bulk/injection) · Yield strength: typical, tensile stress at yield 23 °CPlastic ABS (bulk/injection) · Flexural strength: typical, 23 °CPlastic ABS (bulk/injection) · Elongation at break: nominal strain at break, 23 °CPlastic ABS (bulk/injection) · Young's modulus (stiffness): typicalPlastic ABS (bulk/injection) · Density: typicalPlastic ABS (bulk/injection) · Thermal conductivity: typicalPlastic ABS (bulk/injection) · Thermal expansion: rangePlastic ABS (bulk/injection) · Max service temperature: HDT 1.8 MPa (annealed 4 h/80 °C)
2
Linatex Premium Rubber Spec Sheet (WMD0118, 2023)Weir MineralsRubber · Ultimate tensile strength: typicalRubber · Elongation at break: typicalRubber · Density: typical (specific gravity)Rubber · Max service temperature: continuous use operating range
3
Engineering Polymers Part and Mold Design: Thermoplastics, A Design GuideCovestroarchived copyPlastic ABS (bulk/injection) · Poisson's ratio: typical, ABS family (Covestro Part and Mold Design guide, Table 3-1)
4
Compressibility of Natural Rubber at Pressures Below 500 kg/cm², J. Res. NBS 68A (1964)National Institute of Standards and Technologyarchived copyRubber · Poisson's ratio: government (NBS J. Res. 68A, 1964): computed by NBS for peroxide-cured gum NR vulcanizate, 25 °C, infinitesimal deformation (0.49 in the solver: the linear element locks as the ratio nears 0.5 (nearly incompressible).)Rubber · Specific heat: government (NBS J. Res. 68A, Table 7; values observed for unvulcanized NR by Bekkedahl and Matheson), 25 °C
5
Thermal Conductivity of Soft Vulcanized Natural Rubber: Selected Values (AD 643325)Defense Technical Information Centerarchived copyRubber · Thermal conductivity: government selected value (US Army Natick Laboratories TR 66-49-PR, 1966), soft vulcanized natural rubber, 25 °C

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 ABS (bulk/injection) stronger than Rubber?

Plastic ABS (bulk/injection) is stronger: its yield strength is 45 MPa against tensile strength 23 MPa for Rubber (1.96x).

Which is lighter, Plastic ABS (bulk/injection) or Rubber?

Rubber is lighter: 960 kg/m³ against 1,040 kg/m³ for Plastic ABS (bulk/injection).

Which is lighter for the same job, Plastic ABS (bulk/injection) or Rubber?

For the same stiffness or strength: Plastic ABS (bulk/injection) is lighter for a strong rod or tie, strong beam, strong panel or plate.

Part that must be	Plastic ABS (bulk/injection)	Rubber
Strong rod or tie	lighter	1.81x heavier
Strong beam	lighter	44% heavier
Strong panel or plate	lighter	29% 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 is more ductile, Plastic ABS (bulk/injection) or Rubber?

Rubber stretches further before it breaks: 830% elongation at break against 10% for Plastic ABS (bulk/injection).

Thermal

Which conducts heat better, Plastic ABS (bulk/injection) or Rubber?

Plastic ABS (bulk/injection) conducts heat better: 0.17 W/m·K against 0.151 W/m·K for Rubber.