Rational design of POSS containing low dielectric resin for SLA printing electronic circuit plate composites

Abstract

Manufacturing low dielectric constant composites with on-demand macroscopic shape and size is essential for the development of communication-related technologies. Herein, we report a simple method for preparing 3D printed composites with low dielectric constant through the introduction of polymerizable methacryloxypropyl cage polyhedral silsesquioxane (POSS) components into methacrylate-terminated epoxy resin (MEP) matrix, which the dielectric properties of the POSS/MEP composites can be adjusted by varying the loading of POSS. With the addition of 30 wt% POSS, the dielectric constant of composite is as low as 2.68 at 1 MHz, which can be attributed to the intrinsic pores from the POSS components. Additionally, the elongation at break and toughness of this particular composite increase to 1.40% and 15.0 MJ/m3, respectively, while Td5 (the temperatures at which the samples lose 5% their mass) of MEP/POSS composite exceeds 320 °C, indicating its excellent thermal stability. The differential scanning calorimetry (DSC) results show that the on-set thermal-curing temperature of MEP/POSS composites decreases with the increase of POSS loading content, suggesting that reactivity of composite resins can be enhanced through the introduction of POSS. Further, the MEP/POSS composites had a viscosity ranging from 2.05 to 2.40 Pa s, enabling it to be highly suitable for 3D printing resins. Collectively, these excellent properties make MEP/POSS composites to be a promising, alternative resin for fabricating low dielectric constant materials through stereolithography (SLA) based additive manufacturing.