Scratch resistance of high performance polymers

Scratch tests were carried out on various high performance polymers, including (1) polybenzimidazole (PBI), (2) polyparaphenylene (PPP), (3) polyetheretherketone (PEEK), and (4) polyimide (PI). The scratch damage features were characterized using laser confocal and scanning electron microscope. Scratch resistance at room temperature decreased in the same order as the materials are listed above. It was attempted to correlate the scratch depth with basic mechanical properties, such as Young's modulus, tensile strength, and scratch hardness. Also, the scratch coefficient of friction was considered as a possible measure to differentiate between the various materials tested.

► The polymers tested here have a much higher scratch resistance than classical engineering plastics.
► Scratch patterns were made clearly visible by laser confocal microscopy.
► Scratch resistance correlates reasonably with elastic modulus and scratch hardness.