Graphene nanoplatelets/hydroxyapatite in PMMA composites for enhanced electrical properties

In this article, the casting method was used to prepare PMMA/hydroxyapatite nanocomposite films incorporated with contents graphene nanopalates (Gnp) of nano-size with combined loadings ranging from 0.5 to 1.5 weight %. The nanocomposite was characterized using Fourier transforms infrared (FTIR) spectroscopy, and. Scanning Electron Microscopy (SEM) analysis of the prepared sample, thermal conductivity, and the electrical properties at (1-10MHz) of the samples. The results for FT-IR, and SEM showed that the resulting material had a low agglomerated state, with multiple wrinkles of graphene flakes in the matrix of the PMMA. The thermal conductivity increased and improvement between (0.05–1.82) w/m.k and the electrical properties of nanocomposites revealed a significant improvement with increasing the amount of graphene also that exponent s between (1.25 < s < 1.35). The values of real part ɛ' and imaginary part ɛ’’ were reduced at the lower frequency and became constant at high frequency attributed to the relaxation time. The values of ε″ are high at low frequencies and it is decrease with increase frequencies due to polarization effects or to the dipoles not begins to follow the field variation at higher frequencies. The increase in tan δ with increase in Gnp content due to interfacial polarization mechanism occurred in the films corresponding to frequencies.