At One Place

Natural rubber

Density of natural rubber
950 kg/m³ (920–1,000)
0.95 g/cm³ · 59.3 lb/ft³

Still unbeaten for tear strength and for the ability to stretch several hundred percent and come back, which is why heavy truck and aircraft tyres use natural rubber where car tyres use synthetics. It has the opposite of normal thermal behaviour: a stretched rubber band contracts when heated, because heat randomizes the stretched-out molecules. Its weaknesses are ozone and oil — both crack or swell it — and latex protein allergy, which is what pushed surgical gloves towards nitrile.

Properties

Density
950 kg/m³ (920–1,000) — 0.95 g/cm³
Tensile strength
20–30 MPa
Young's modulus
0.003 GPa
Thermal conductivity
0.13 W/(m·K)
Thermal expansion
220 µm/(m·K)
Floats in water
Yes
Magnetic
No

What it is used for

  • Truck and aircraft tyre carcasses
  • Anti-vibration engine and building mounts
  • Surgical gloves and elastic bands
  • Conveyor belts and hoses

How it compares

Water is 1,000 kg/m³. Anything with a shorter bar than water floats in it.

air 1.2 kg/m³
expanded polystyrene foam 20 kg/m³
rigid polyurethane foam 40 kg/m³
natural rubber 950 kg/m³
Water — the float line 1,000 kg/m³
tungsten 19,250 kg/m³
gold 19,300 kg/m³
platinum 21,450 kg/m³
Water is 1,000 kg/m³. Anything below that floats.
Material Density Relative to water
rigid polyurethane foam 40 kg/m³ 0.04×
expanded polystyrene foam 20 kg/m³ 0.02×
air 1.2 kg/m³ 0.00×
natural rubber ← 950 kg/m³ 0.95×
platinum 21,450 kg/m³ 21.45×
gold 19,300 kg/m³ 19.30×
tungsten 19,250 kg/m³ 19.25×

Does it rust?

Natural rubber contains no iron, so it cannot rust. Whether it degrades depends on the material, not on oxidation.

Is it magnetic?

Natural rubber is not a metal and has no ferromagnetic response.

Common questions

What is the density of natural rubber?
950 kg/m³ (920–1,000), or 0.95 g/cm³.
Does natural rubber float?
Yes. At 950 kg/m³ it is less dense than water's 1,000.
Is natural rubber magnetic?
Natural rubber is not a metal and has no ferromagnetic response.

Related pages

Sources

  1. Typical range compiled from manufacturer specifications — At One Place

How these figures are compiled and checked