Zhang Xiaolin, Hassanzadeh Pegah, Miyake Takeo, Jin Jungho, Rolandi Marco
Department of Electrical Engineering, University of California, Santa Cruz, CA 95064, USA.
J Mater Chem B. 2016 Apr 7;4(13):2273-2279. doi: 10.1039/c6tb00106h. Epub 2016 Mar 9.
Natural biological composites often couple light weight with tunable and spatially controlled mechanical properties including stiffness, toughness, and hardness. Examples include the toughness of seashells, the hardness of the chiton tooth, and the stiffness gradient of the squid beak. While seashells and the chiton tooth have a mineralized inorganic component, the squid beak is entirely organic. The squid beak is known as one of the hardest fully organic materials. The hydrated squid beak has a large stiffness gradient from soft, at the interface with the squid mouth, to hard at the tip. This gradient occurs from the spatially controlled cross-linking of chitin nanofibers with a protein matrix aided by catecholamines. Here, we introduce a water processable deacetylated chitin composite with tunable mechanical properties from spatially controlled cross-linking assisted by catecholamines. Given the natural abundance of chitin and the ease of water processing, this composite can find applications for bridging mechanically mismatched materials.
天然生物复合材料通常兼具轻质以及可调节的、空间可控的机械性能，包括刚度、韧性和硬度。例如，贝壳的韧性、石鳖齿的硬度以及鱿鱼喙的刚度梯度。虽然贝壳和石鳖齿含有矿化的无机成分，但鱿鱼喙完全是有机的。鱿鱼喙是已知最硬的全有机材料之一。水合状态的鱿鱼喙具有很大的刚度梯度，从与鱿鱼嘴相接处的柔软状态到喙尖的坚硬状态。这种梯度是由儿茶酚胺辅助的几丁质纳米纤维与蛋白质基质在空间上可控的交联作用产生的。在此，我们介绍一种可通过水加工的脱乙酰几丁质复合材料，其机械性能可通过儿茶酚胺辅助的空间可控交联作用进行调节。鉴于几丁质的天然丰富性以及水加工的简便性，这种复合材料可用于连接机械性能不匹配的材料。
