Sulfone polymers are extremely tough and do not break in standard unnotched impact tests. They retain their toughness and strength over time, unlike polyetherimide (PEI) which exhibits a significant loss of impact strength and becomes brittle.

Retention of Tensile Strength



Retention of Impact Strength



The impact strength of test plaques heat aged at 190°C (375°F) for 170 hours was evaluated using a Gardner falling dart impact tester. Radel® PPSU absorbs significantly higher impact force than polyetherimide (PEI) without cracking or breaking.


Falling Dart Impact Test