Polyphenylene Ether Enables Low Dielectric Photosensitive Acrylate Resins with Enhanced Mechanical Properties for UV‐Assisted Direct Ink Writing

ABSTRACT

Additive manufacturing has emerged as a transformative technology for manufacturing high‐frequency printed circuit boards. Acrylate‐based photosensitive resins are widely employed in such processes owing to their fast‐curing speed and high printing precision. However, acrylate‐based systems still present considerable challenges for 3D‐printed circuits, mainly due to inherent drawbacks including inadequate toughness, low tensile strength, and high dielectric loss. Herein, polyphenylene ether (PPO)‐modified acrylate photosensitive resins are designed and prepared to tackle these issues. The introduction of PPO endows the inks with pronounced shear‐thinning behavior and rapid thixotropic recovery, thus facilitating smooth extrusion and high‐fidelity direct ink writing. The optimized formulations exhibit remarkably enhanced tensile properties with tensile strength increased from 28 to 74 MPa, while elongation at break rises from 2.7% to 8.8%. The dielectric constant and loss decrease from 3.06 to 2.53 and 0.016 to 0.012 at 5 GHz, respectively, accompanied by reduced water absorption from 1.74% to 1.39%. These results demonstrate that PPO serves as an effective modifier that overcomes the inherent drawbacks of conventional UV‐curing acrylate resins. Overall, this study offers a promising strategy for developing photosensitive inks for 3D printing and additive manufacturing technologies.