Ucar Seniz, Nielsen Anne R, Mojsoska Biljana, Dideriksen Knud, Andreassen Jens-Petter, Zuckermann Ronald N, Sand Karina K
Department of Chemical Engineering, Norwegian University of Science and Technology, Trondheim 7491, Norway.
Department of Metallurgical and Materials Engineering, Middle East Technical University, Ankara 06800, Turkiye.
ACS Appl Mater Interfaces. 2024 Apr 17;16(15):19496-19506. doi: 10.1021/acsami.4c00434. Epub 2024 Apr 3.
Mineral-polymer composites found in nature exhibit exceptional structural properties essential to their function, and transferring these attributes to the synthetic design of functional materials holds promise across various sectors. Biomimetic fabrication of nanocomposites introduces new pathways for advanced material design and explores biomineralization strategies. This study presents a novel approach for producing single platelet nanocomposites composed of CaCO and biomimetic peptoid (N-substituted glycines) polymers, akin to the bricks found in the brick-and-mortar structure of nacre, the inner layer of certain mollusc shells. The significant aspect of the proposed strategy is the use of organic peptoid nanosheets as the scaffolds for brick formation, along with their controlled mineralization in solution. Here, we employ the B28 peptoid nanosheet as a scaffold, which readily forms free-floating zwitterionic bilayers in aqueous solution. The peptoid nanosheets were mineralized under consistent initial conditions (σ = 1.2, pH 9.00), with variations in mixing conditions and supersaturation profiles over time aimed at controlling the final product. Nanosheets were mineralized in both feedback control experiments, where supersaturation was continuously replenished by titrant addition and in batch experiments without a feedback loop. Complete coverage of the nanosheet surface by amorphous calcium carbonate was achieved under specific conditions with feedback control mineralization, whereas vaterite was the primary CaCO phase observed after batch experiments. Thermodynamic calculations suggest that time-dependent supersaturation profiles as well as the spatial distribution of supersaturation are effective controls for tuning the mineralization extent and product. We anticipate that the control strategies outlined in this work can serve as a foundation for the advanced and scalable fabrication of nanocomposites as building blocks for nacre-mimetic and functional materials.
自然界中发现的矿物-聚合物复合材料具有对其功能至关重要的卓越结构特性，将这些特性应用于功能材料的合成设计有望在各个领域取得成果。纳米复合材料的仿生制造为先进材料设计引入了新途径，并探索了生物矿化策略。本研究提出了一种生产由碳酸钙和仿生类肽（N-取代甘氨酸）聚合物组成的单血小板纳米复合材料的新方法，类似于某些软体动物贝壳内层珍珠质的砖石结构中的砖块。所提出策略的重要方面是使用有机类肽纳米片作为砖块形成的支架，以及它们在溶液中的可控矿化。在这里，我们使用B28类肽纳米片作为支架，它在水溶液中很容易形成自由漂浮的两性离子双层。类肽纳米片在一致的初始条件（σ = 1.2，pH 9.00）下进行矿化，随着时间的推移，混合条件和过饱和度分布会发生变化，旨在控制最终产物。纳米片在反馈控制实验（通过滴定剂添加持续补充过饱和度）和无反馈回路的分批实验中均进行了矿化。在特定条件下通过反馈控制矿化实现了无定形碳酸钙对纳米片表面的完全覆盖，而在分批实验后观察到的主要碳酸钙相是球霰石。热力学计算表明，随时间变化的过饱和度分布以及过饱和度的空间分布是调节矿化程度和产物的有效控制因素。我们预计，这项工作中概述的控制策略可以作为纳米复合材料先进且可扩展制造的基础，这些纳米复合材料可作为仿珍珠质和功能材料的构建块。
