Investigation of thermal and electrical properties of nanoparticle doped epoxy resin

In this thesis, 3D constructed graphite nanoparticle (GnP) structures with and without PVP functionalization were produced utilizing water-soluble polymers. PVP and PEG polymer are used as a skeleton for GnP to deposit on and create pathways throughout polymer construction. For this purpose, PVP and PEG polymers are dissolved in pure water, followed by freeze-drying to obtain GnP-polymer aerogel. The prepared aerogels were exposed to heat treatment at 200oC to produce a compact structure and to prevent the dissolution of aerogels in the epoxy resin. Various analytical techniques, including FTIR, TGA, and DSC were employed to characterize the chemical interactions of the structures thermal decomposition and Tg determination of the samples produced. The electrical conductivity of composites was investigated according to the two-point probe and frequency-dependent conductivity testing. Scanning Electron Microscope (SEM) was used for microstructural and fracture surface examination of aerogel before and after the heat treatment. As a result, ıt was found that GnP aerogel-epoxy composite samples were successfully produced by keeping the aerogel intact within the epoxy matrix. Heat-treated aerogels were shown to have porous structure with smaller porosity sizes. Also interaction between water-soluble polymers and epoxy indicates that Tg of epoxy decreases with the addition of PEG polymer. Unlike PEG addition PVP addition with high GnP content increases Tg of epoxy composites. The electrical conductivity of the produced epoxy composite was measured as 1,34×10-6 S/m with 0,596 wt % GnP addition indicating that 320 times higher electrical conductivity per gram of GnP.