Thermal and dielectric properties enhancement of photocurable acrylate polymers for digital light processing 3D printed electronics

Digital light processing 3D printing has been rapidly evolving conventional manufacturing industry with the most meticulous resolution and strongest layer‐to‐layer adhesion among all additive manufacturing techniques. In this study, to improve poor polymer thermal stability and dielectric properties from prevailing methyl methacrylate‐based resin, tri‐functional trimethylolpropane tri‐acrylate (TMPTA) is introduced to form a stable polymer network. Meanwhile, monomers carrying non‐polar, bulky adamantane are added to eradicate poly‐TMPTA's notorious high cracking and warping tendency. Test results showed both high 1‐adamantyl methacrylate and 1, 3‐adamantyl di‐acrylate (ADDA) additions can print crack‐free samples. However, only ADDA addition keeps low CTE (82.86 ppm/oC, 200 ~ 260°C) and cuts down Df (0.02, 10 GHz). TMPTA polymer network modifications of both additions are explored. By contrast, poly‐MMA exhibits much higher CTE (323.44 ppm/oC) and Df (0.035). A 3D‐printed curvilinear circuit board from above resin formulation with electroplated copper circuits successfully passes lead‐free level reflow without deformation.