Fabrication process optimization and characterization of nHA-CNTs reinforced PEEK hybrid nanocomposite

Compression molding is the leading fabrication process for polymer composites. The settings of process parameters highly influence the mechanical properties of composites. This manuscript optimizes the ball mixing and compression molding process parameters for the fabrication of PEEK, multiwall carbon nanotubes, and nano-hydroxyapatite-based hybrid nanocomposite by the Taguchi method. The elastic modulus examined by the nanoindentation method of static mechanical analysis was taken as the output response variable. The optimum levels of mixing time, mold temperature, mold pressure, and holding time process parameters for maximum elastic modulus were found to be 90 minutes, 400 °C, 150 bar, and 15 minutes, respectively. The ‘Analysis of Variance’ technique analyzed that the mold temperature had the highest contribution (46.82%) in enhancing the elastic modulus to the largest value. The elastic modulus and hardness of PEEK-based hybrid nanocomposite with 30 wt.% nHA and 3 wt.% MWCNTs were observed to be 83% and 65% more than that of pure PEEK. The hydrophilicity of PEEK was improved with the reinforcement of nHA, attributed to the presence of oxygen-containing functional groups in the chemical structure of nHA.