Plastic Nylon vs. Rubber

Compare Plastic Nylon vs. Rubber strength, stiffness, weight and thermal properties.

RubberBulk polymer (molded or machined)

Mechanical	Plastic Nylon	Rubber
Yield strength	63.1MPa1	not given (tensile used)
Ultimate tensile strength	63.1MPa12.74x stronger	23MPa2
Flexural strength	82.9MPa1	not sourced
Elongation at break	not sourced	830%2
Young's modulus (stiffness)	2.33GPa1	not sourced
Density	1,140kg/m³1	960kg/m³219% lighter
Strength to weight	55.4kN·m/kg2.31x higher	24kN·m/kg
Stiffness to weight	2.04MN·m/kg	not sourced
Poisson's ratio	base material0.43	government0.54
Shear modulus	0.833GPa	not sourced
Bulk modulus	3.89GPa	not sourced
Speed of sound	1,430m/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 Nylon	Rubber
Thermal conductivity	base material0.33W/m·K52.19x more heat through a fin	0.151W/m·K6
Thermal expansion	base material98–102µm/m·K5	not sourced
100 mm part over a 50 °C swing	500µm growth	not sourced
Specific heat	base material1,700J/kg·K5	government1,881J/kg·K4
Heats up and cools (diffusivity)	0.17mm²/s2.04x faster	0.0836mm²/s
Thermal shock resistance	53.6W/m	not sourced
Melting point	188°C1	not sourced
Glass transition	55.1°C1	not sourced
Max service temperature	HDT 0.455 MPa89.2°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

Try it on a partA bracket to run stress or thermal on, free in your browser	Open in LessCAD	Open in LessCAD

Sources6 documents: UltiMaker, Weir Minerals, Covestro, National Institute of Standards and Technology, BASF, Defense Technical Information Center

Plastic Nylon: Ultimaker Nylon, 3D-printed specimens, XY (flat), conditioned >=24 h at room temperature; Ultimaker S5 Pro, engineering intent profile, 0.15 mm layer height, AA 0.4 print core, 100% infill, Cura 4.9, printed one-at-a-time, conditioned >=24 h at room temperature. TDS v2.00, April 20, 2022.
Rubber: Weir Minerals Linatex Premium rubber (95 % natural rubber), typical physical properties, spec sheet WMD0118/202305

1
Ultimaker Nylon Technical Data Sheet, v5.00UltiMakerarchived copyPlastic Nylon · Yield strength: typicalPlastic Nylon · Ultimate tensile strength: typical, peak stress (= stress at yield)Plastic Nylon · Flexural strength: typicalPlastic Nylon · Young's modulus (stiffness): typicalPlastic Nylon · Density: typicalPlastic Nylon · Melting point: typicalPlastic Nylon · Glass transition: typicalPlastic Nylon · Max service temperature: HDT 0.455 MPa (printed specimens)
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 GuideCovestroPlastic Nylon · Poisson's ratio: base material: unfilled polyamide (PA), conditioned, maker design-guide family value (Covestro 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
Ultramid (PA) Product RangeBASFPlastic Nylon · Thermal conductivity: base material: unreinforced BASF Ultramid PA66 (A3K) and PA6 (B3S), 23 C (same value for both)Plastic Nylon · Thermal expansion: base material: unreinforced BASF Ultramid PA66 (A3K, 98) and PA6 (B3S, 102), 23-55 CPlastic Nylon · Specific heat: base material: unreinforced BASF Ultramid PA66 (A3K) and PA6 (B3S), 23 C (same value for both)
6
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.

Plastic Nylon is 3D printed: its properties depend on build direction and print settings; these are typical values.

Questions

Mechanical

Is Plastic Nylon stronger than Rubber?

Plastic Nylon is stronger: its yield strength is 63.1 MPa against tensile strength 23 MPa for Rubber (2.74x).

Which is lighter, Plastic Nylon or Rubber?

Rubber is lighter: 960 kg/m³ against 1,140 kg/m³ for Plastic Nylon.

Which is lighter for the same job, Plastic Nylon or Rubber?

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

Part that must be	Plastic Nylon	Rubber
Strong rod or tie	lighter	2.31x heavier
Strong beam	lighter	1.65x heavier
Strong panel or plate	lighter	39% 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).

Thermal

Which conducts heat better, Plastic Nylon or Rubber?

Plastic Nylon conducts heat better: 0.33 W/m·K against 0.151 W/m·K for Rubber.