Shaked H, Polishchuk I, Nagel A, Bekenstein Y, Pokroy B
Department of Materials Science and Engineering and the Russell Berrie Nanotechnology Institute, Technion - Israel Institute of Technology, Haifa, 32000, Israel.
Mater Today Bio. 2021 Jun 19;11:100120. doi: 10.1016/j.mtbio.2021.100120. eCollection 2021 Jun.
Biominerals formed by organisms in the course of biomineralization often demonstrate complex morphologies despite their single-crystalline nature. This is achieved owing to the crystallization via a predeposited amorphous calcium carbonate (ACC) phase, a precursor that is particularly widespread in biominerals. Inspired by this natural strategy, we used robocasting, an additive manufacturing three-dimensional (3D) printing technique, for printing 3D objects from novel long-term, Mg-stabilized ACC pastes with high solids loading. We demonstrated, for the first time, that the ACC remains stable for at least a couple of months, even after printing. Crystallization, if desired, occurs only after the 3D object is already formed and at temperatures significantly lower than those of common postprinting sintering. We also examined the effects different organic binders have on the crystallization, the morphology, and the final amount of incorporated Mg. This novel bio-inspired method may pave the way for a new bio-inspired route to low-temperature 3D printing of ceramic materials for a multitude of applications.
生物矿化过程中生物体形成的生物矿物，尽管其本质为单晶，但往往呈现出复杂的形态。这是通过经由预沉积的无定形碳酸钙（ACC）相结晶来实现的，ACC是一种在生物矿物中特别普遍的前体。受此自然策略的启发，我们使用了3D打印技术中的挤出式打印，从具有高固体含量的新型长期Mg稳定ACC糊剂中打印3D物体。我们首次证明，即使在打印后，ACC至少能保持几个月的稳定性。如果需要，结晶仅在3D物体已经形成后且在远低于常见后打印烧结的温度下发生。我们还研究了不同有机粘合剂对结晶、形态以及最终Mg掺入量的影响。这种新型的受生物启发的方法可能为一种新的受生物启发的低温3D打印陶瓷材料的途径铺平道路，可用于多种应用。
