What does a higher heat deflection temperature indicate for a polymer under load?

What does a higher heat deflection temperature indicate for a polymer under load?

• A. Better heat resistance under load.
• B. Lower heat resistance.
• C. Higher density.
• D. Higher modulus in tension.

Answer: (A)

Heat deflection temperature shows how well a polymer resists softening when it is under load as temperature rises. A higher heat deflection temperature means the material can stay rigid and bear load at higher temperatures, so its heat resistance under load is better. Density doesn’t indicate how a material deforms under heat under load, and tensile modulus tells stiffness at a given temperature rather than the temperature at which deformation starts. So, choosing a material with a higher HDT improves performance in thermally demanding, loaded conditions.

Heat deflection temperature shows how well a polymer resists softening when it is under load as temperature rises. A higher heat deflection temperature means the material can stay rigid and bear load at higher temperatures, so its heat resistance under load is better. Density doesn’t indicate how a material deforms under heat under load, and tensile modulus tells stiffness at a given temperature rather than the temperature at which deformation starts. So, choosing a material with a higher HDT improves performance in thermally demanding, loaded conditions.