Roles of chemistry modification for surface wettability of Polyether-Ether-Ketone (PEEK) by ultraviolet laser ablation

Tailoring the functionality of Polyether-ether-ketone (PEEK) is critical for enhancing its application, which can be accomplished by the modification of surface morphology and chemistry. In the present work, we experimentally demonstrate the correlation of modified chemical composition of textured PEEK surface by 355 nm UV nanosecond pulsed laser ablation with enhanced surface wettability. Specifically, the impact of UV laser processing parameters on microgroove morphology and ablated surface quality of PEEK surface is evaluated, with which high precision grid surface textures with uniform ablation quality are fabricated. The modification of chemical elements and functional groups of textured PEEK surface by the laser ablation is further analyzed by XPS spectra characterization, which demonstrates the substantial change of C=O and O-C=O bonds, as well as freshly generated polar carboxylic acid groups. Experimental results indicate that the surface composition modification greatly increases surface polarity and surface free energy of textured PEEK surface accompanied by enhanced surface wettability.