Incorporation of graphene nanoplatelets/hydroxyapatite in PMMA bone cement for characterization and enhanced mechanical properties of biopolymer composites

Polymethylmethacrylate (PMMA) in powder form is broadly used as bone cement in orthopedic applications due to its expanded mechanical, physical, and chemical properties. In this study, a hybrid PMMA biopolymer nanocomposite is developed by the supplement of graphene nanoplatelets (GnP) and hydroxyapatite (HA) powders of nano-size with combined loadings ranging from 0.5 to 2.5 weight %. Both materials were applied uniformly to reinforce commercial bone cement made of polymethylmethacrylate. The findings showed that adding 1.5 wt.% of combined HA and GnP nanoparticles to the powder of PMMA bone cement resulted in the expansion of flexural strength by 49.28%, the flexural modulus by 30.80%, the compression strength by 31.7%, and the compression modulus by 57.41%. The nanocomposite was characterized using Energy Dispersive X-Ray Analysis (EDS), Fourier transforms infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) to study the distribution of reinforced nanoparticles. Scanning Electron Microscopy (SEM) analysis of the prepared samples and fractured surface shows the proper dispersion of nanofillers into the matrix phase and possible reasons behind fracture. The inclusion of GnP and HA in the PMMA enhances the mechanical performances required for biomedical components. Also, the SEM findings of the mechanically tested broken surface of the polymer nanocomposite samples demonstrated the feasibility of the proposed material for joint replacement surgical procedures and orthopedic implants.