Thermophysical properties of low viscosity epoxy resin with the addition of boron phases for dual-use military and civilian applications

Abstract

The study presents a comprehensive analysis of low-viscosity resin composites with boron carbide (BC) and hexagonal boron nitride (BN) additions to modify their rheological, elastic, heat-transfer, and thermal-stability properties. The analyses being conducted are related to a specific dual application, rapidly produced through a simple mixing process. The main purpose of their use is to dissipate the energy of moving vehicles and the heat transferred to the material. They can also be used, because of the low viscosity, in various other applications, ranging from filling hard-to-reach areas, to bonding layers or impregnating materials such as ballistic fabrics. Various thermal analysis techniques, such as thermogravimetry, differential scanning calorimetry, laser flash analysis and dynamic mechanical analysis were used to assess their properties. Modulus values of up to 5.5 GPa were obtained at a frequency of 20 Hz and a temperature of –60°C, compared to 4.0 GPa for the pure resin. A temperature of 50°C was selected as the upper limit, where a value of 1.7 GPa was obtained for a 10 vol.% BCBN blend, compared to 1.2 GPa for the pure resin. Materials with thermal conductivity nearly three times higher than that of pure resin have been obtained. These findings suggest that incorporating boron-based ceramic fillers enables effective tuning of both the thermomechanical performance and the heat-transfer characteristics of low-viscosity epoxy systems. Such behaviour indicates their potential for use in multifunctional structures that require simultaneous mechanical stability and enhanced thermal management.