Novel Terpene-Reinforced Photopolymerizable Resins Derived from Methacrylate Salts of Imidazole

This research aims to develop new 3D (three-dimensional) printable resins made from methacrylate salts of imidazole, 2-methyl-imidazole, and 1-methyl-imidazole, with glycerol trimethacrylate serving as a crosslinking agent. With their backbone structure, these resins are easy and rapid to prepare, offering an alternative to conventional ones. Reinforced with terpene-based additives such as α-pinene, (R)-limonene, trans-ethyl cinnamate, and safrole, they present a diverse range of fifteen resin formulations. Each resin underwent printability tests, including printing tests, which revealed accuracy, precision, and dimensional stability compared to a commercial resin and its respective digital 3D models. Mechanical tests further demonstrated that adding alpha-pinene and (R)-limonene enhanced hardness, while safrole had the opposite effect. Resins containing α-pinene and (R)-limonene as additives showcased an elasticity modulus comparable to the commercial resin. According to mechanical tests, a cytocompatibility assay was conducted for the best resin, showing that this resin holds potential for developing drug delivery systems and other biomedical devices.