Surface modification of polyetheretherketone by grafting amino groups to improve its hydrophilicity and cytocompatibility

Although special engineering plastics polyether ether ketone (PEEK) have many excellent properties, its hydrophobicity and biological inertia limit its application in the field of implant materials. In this study, amino modification of PEEK was conducted to endow it with good hydrophilicity and bioactivity. PEEK was sulfonated with concentrated sulfuric acid, and reacted with sulfoxide chloride to obtain aromatic sulfonyl chloride. Finally, amino (–NH2) was introduced onto the surface of PEEK by acylation reaction between acyl chloride group and ethylenediamine (EDA) to improve its hydrophilicity and cell compatibility. The PEEKs before and after modification were characterized by FTIR, XPS and WCA. The cell compatibility was evaluated by human umbilical vein endothelial cells (HUVEC). The results showed that –NH had been successfully introduced onto the surface of PEEK, and the hydrophilicity of the aminated PEEK was significantly improved. Compared with the PEEK before amino modification, the aminated PEEK significantly promoted adhesion and spread of cells, indicating good cell compatibility. This study breaks through the limitations of traditional wet chemical methods and provides a new way for further modification of PEEK.