Effective Thermal Conductivity of h-BN Filled Epoxy Composites

Abstract

An optimum solution of heat dissipation has been a consistent requirement after development of electronics devices. These require materials which possesses high thermal conductivity as well as low dielectric constant. Development of polymer composite with desired characteristics could be the solution this problem. In his work it has been tried to study enhancement of the effective thermal conductivity of epoxy polymer composite if h-BN powder is added in it in different volume fraction. Initially a mathematical model was developed and correlations were established to measure effective thermal conductivity of polymer composites for number of volume fractions of particulate added. Further number of epoxy polymer composites reinforced with h-BN filler material was prepared by conventional hand lay-up method in which filler content ranged from 0% to 28.18%. Subsequently effective thermal conductivity of prepared composites were measured by UnithermTM Model 2022 in accord with ASTM-E1530 standard. Analytical study shows that after 26 % volume percentage there is a sharp enhancement in effective thermal conductivity of composite. This sudden rise in effective thermal conductivity is due to the overlap between filler particle which leads to the formation of conductive chain. The volume percentage after which this phenomenon occur is termed as percolation threshold.