Improved thermal, dielectric, and mechanical properties of acrylate composites with diethylene glycol and silane-treated ternary hybrid fillers via three-dimensional vat photopolymerization

Rapid advances in electronic devices have led to the production of highly integrated structures, which are prone to the thermal accumulation problem. Accordingly, polymer-based composites have been introduced to solve the thermal dissipation problem and endow energy storage properties. In this study, an acrylate polymer-based composite with boron nitride (BN), barium titanate (BT), and carbon nanotubes (CNTs) ternary fillers was fabricated via three-dimensional (3D) vat photopolymerization (VPP). To improve the processability of the printing, diethylene glycol (DEG) was added as a viscosity reducer, and ternary fillers were surface-treated with silane functional groups. The surface-treated ternary composite improved tensile strength, thermal conductivity, and dielectric constant compared to a composite composed of raw ternary fillers. Furthermore, the composites with silane-treated BN and CNTs showed thermal conductivity of 2.796 W/(m∙K) and thermal conductivity enhancement of 1153% compared to the acrylate matrix. The dielectric constants and electrical insulation of the composites were also investigated. The proposed method ushers a new era in polymer-based composites with improved thermal conductivity and energy storage properties as well as desired and controlled complex structures through swift and sophisticated 3D VPP printing.