Synthesis and Characterisation of Polytetrafluoroethylene Composite for Electrical Insulation and Dielectrics

This work provides an experimental study to measure the electrical properties of Polytetrafluoroethylene polymer and how it improves through the process of mixing with different volume rates of Poly (methyl methacrylate) PMMA. The relationship of the actual dielectric constant with frequency for pure and dopped models with different concentrations of PMMA (5%, 7%, 10%) and for a range of frequencies ranging between 1-1000 KHz, at the room temperature was investigated. The results show an increase in the dielectric constant of the composites compared to the pure models for all concentrations, which indicates that the polymers interaction gives support to the polytetrafluoroethylene infrastructure. The mixing process, also, leads to an increase in the values the imaginary part of the dielectric constant compared to the pure model, and this is due the significant increase in the number of dipoles resulting from the addition process which in turn led to increase the amount of energy lost due to rotation or friction of the dipoles with each other. This increase, in turn, led to a corresponding rise in the values of the loss tangent tanδ and the AC conductivity of the models. The experimental results show a 90 % increase in the dielectric constant of the composite at 500 KHz compared to the pure Polytetrafluoroethylene, which provide a good electrical insulation material for electronic circuits.