Polyurethane

Tough Enough for the Job

Polyurethanes or Urethanes are terms that are used interchangeably for a family of elastomers that were invented as ‘artificial rubbers’ during World War II.

Polyurethane is an elastomeric material with outstanding properties and wear characteristics. Urethane is a generic term but how the urethane is manufactured and fabricated determines how effective it is in a specific application.

Polyurethane elastomers are a unique breed of engineering materials that combine the advantages of rigid plastics, metals and ceramics with the flexibility and elasticity of rubber.

Western Polymers manufactures solid thermoset castable elastomers:

prepolymer + curative + heat + appropriate cure time = cured polyurethane part.

Once the reactions between the prepolymer and the curative have ceased, the polyurethane is cured and it cannot be heat shaped without degradation. This thermal stability results from the degree of cross-linking of polymer chains.

At one end polyurethanes can be processed to form a compound as soft as bubble-gum. At the other end they can be as hard as a soft metal. The wide ranges of hardness’s make them an extremely versatile material unlike any other.

This makes useful in a variety of applications. The typical rubber compound cannot surpass the hardness range of castable urethanes without becoming brittle. The typical plastic compound cannot give you the elasticity without tears or breaks.

An elastomer can be described as a material characterized by the property of high elasticity. This means it has the ability to stretch to a great extent under load and recover more or less completely when the load is released. Solid polyurethanes posses this property and can be classed as elastomers.

The base materials used to form polyurethane compounds are a by-product of the oil refining process.