This study aimed at developing polymer-based dielectric materials with high charge-discharge efficiency and large energy density at high temperatures. A polymer nanocomposite was formed using c-BCB polymer matrix with two-dimensional hexagonal boron nitride nanosheets (BNNS). Using a transient technique, thermal conductivity was measured with a Thermal Analyzer. The incorporation of BNNS into PMMA was found to increase thermal conductivity and enhance properties of the nanocomposites....