Synergistic strengthening and toughening of 3D printing photosensitive resin by bismaleimide and acrylic liquid-crystal resin

With the rapid development of 3D printing technology, products with improved performance are in demand. In this study, photosensitive bismaleimide resin (N,N′-(4,4′-diphenylmethane) bismaleimide–4,4′-diaminodiphenyl methane–glycidyl methacrylate; BDM-DDM-GMA) and acrylic liquid-crystal resin (ALCR) were used to obtain new 3D printing BDM/ALCR resins. The resultant 3D-printed products exhibited excellent heat resistance and mechanical properties, and only small amounts of both resins were required to achieve the optimal formulation of a single resin. When 10% of BDM-DDM-GMA and 5% of ALCR were used, their T-5% and Tmax were 329.2 and 459.1 °C, respectively, Tg was 117.4 °C, tensile strength was 81.7 MPa, elongation at break was 14.3%, flexural strength was 134.8 MPa, and impact strength was 5.2 kJ m−2. The use of BDM-DDM-GMA and ALCR fulfills the expectation that the two components can synergistically enhance the performance of 3D printing resins, the presence of the imide ring increases the overall rigidity at the molecular level, and the mesocrystalline domain formed by the stacking of liquid crystal molecules enhances its resistance when subjected to external forces. After the physical printing tests, all products exhibited good surface properties and excellent interlayer bonding. As a result, BDM/ALCR resins with excellent mechanical properties and heat resistance have great potential for applications in aerospace, automotive parts, and electronic components.