Rubber vs. SLA Resin Elastic 50A

Compare Rubber vs. SLA Resin Elastic 50A strength, stiffness, weight and thermal properties.

RubberBulk polymer (molded or machined)

SLA Resin Elastic 50A3D printed (SLA resin)

Mechanical	Rubber	SLA Resin Elastic 50A
Yield strength	not given (tensile used)	not given (tensile used)
Ultimate tensile strength	23MPa16.76x stronger	3.4MPa2
Elongation at break	830%15.19x more ductile	160%2
Young's modulus (stiffness)	not sourced	not sourced
Density	960kg/m³1	1,010kg/m³2
Strength to weight	24kN·m/kg7.12x higher	3.37kN·m/kg
Stiffness to weight	not sourced	not sourced
Poisson's ratio	government0.53	not sourced
Shear modulus	not sourced	not sourced
Bulk modulus	not sourced	not sourced
Speed of sound	not sourced	not sourced

Stiffness against densityHigher and further left: stiffer for its weight

Strength against densityHigher and further left: stronger for its weight

Thermal	Rubber	SLA Resin Elastic 50A
Thermal conductivity	0.151W/m·K4	not sourced
Thermal expansion	not sourced	not sourced
100 mm part over a 50 °C swing	not sourced	not sourced
Specific heat	government1,881J/kg·K3	not sourced
Heats up and cools (diffusivity)	0.0836mm²/s	not sourced
Thermal shock resistance	not sourced	not sourced
Glass transition	not sourced	DMA-34.5°C2
Max service temperature	70°C1	not sourced

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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Sources4 documents: Weir Minerals, Formlabs, National Institute of Standards and Technology, Defense Technical Information Center

Rubber: Weir Minerals Linatex Premium rubber (95 % natural rubber), typical physical properties, spec sheet WMD0118/202305
SLA Resin Elastic 50A: Formlabs Elastic 50A Resin V2 (FLELCL02), TDS Rev. 01 24.01.2024; parts printed on Form 3, 100 µm, Elastic 50A V2 settings and post-processing; tensile on Die C specimens cut from printed sheets after 3+ h at 23 °C.

1
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
2
Elastic 50A Resin V2 Technical Data Sheet (2024)Formlabsarchived copySLA Resin Elastic 50A · Ultimate tensile strength: typicalSLA Resin Elastic 50A · Elongation at break: typicalSLA Resin Elastic 50A · Density: typicalSLA Resin Elastic 50A · Glass transition: DMA
3
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
4
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.

SLA Resin Elastic 50A is 3D printed: its properties depend on build direction and print settings; these are typical values.

Questions

Mechanical

Is Rubber stronger than SLA Resin Elastic 50A?

Rubber is stronger: its tensile strength is 23 MPa against 3.4 MPa for SLA Resin Elastic 50A (6.76x).

Which is lighter, Rubber or SLA Resin Elastic 50A?

Rubber is lighter: 960 kg/m³ against 1,010 kg/m³ for SLA Resin Elastic 50A.

Which is lighter for the same job, Rubber or SLA Resin Elastic 50A?

For the same stiffness or strength: Rubber is lighter for a strong rod or tie, strong beam, strong panel or plate.

Part that must be	Rubber	SLA Resin Elastic 50A
Strong rod or tie	lighter	7.12x heavier
Strong beam	lighter	3.76x heavier
Strong panel or plate	lighter	2.74x 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, Rubber or SLA Resin Elastic 50A?

Rubber stretches further before it breaks: 830% elongation at break against 160% for SLA Resin Elastic 50A.