Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Nature. 2010 Jan 21;463(7279):339-43. doi: 10.1038/nature08693.
With the world's focus on reducing our dependency on fossil-fuel energy, the scientific community can investigate new plastic materials that are much less dependent on petroleum than are conventional plastics. Given increasing environmental issues, the idea of replacing plastics with water-based gels, so-called hydrogels, seems reasonable. Here we report that water and clay (2-3 per cent by mass), when mixed with a very small proportion (<0.4 per cent by mass) of organic components, quickly form a transparent hydrogel. This material can be moulded into shape-persistent, free-standing objects owing to its exceptionally great mechanical strength, and rapidly and completely self-heals when damaged. Furthermore, it preserves biologically active proteins for catalysis. So far no other hydrogels, including conventional ones formed by mixing polymeric cations and anions or polysaccharides and borax, have been reported to possess all these features. Notably, this material is formed only by non-covalent forces resulting from the specific design of a telechelic dendritic macromolecule with multiple adhesive termini for binding to clay.
随着全世界致力于减少对化石燃料能源的依赖，科学界可以研究新的塑料材料，这些材料比传统塑料对石油的依赖程度要低得多。鉴于环境问题日益严重，用基于水的凝胶（所谓的水凝胶）代替塑料似乎是合理的。在这里，我们报告说，水和粘土（质量的 2-3%）与非常少量的有机成分（<质量的 0.4%）混合后，会迅速形成透明的水凝胶。由于其非常高的机械强度，这种材料可以模制成形状保持、独立的物体，并在损坏时迅速且完全自我修复。此外，它还可以保存用于催化的生物活性蛋白质。到目前为止，还没有其他水凝胶（包括通过混合聚合阳离子和阴离子或多糖和硼砂形成的常规水凝胶）被报道具有所有这些特性。值得注意的是，这种材料仅通过特定设计的具有多个用于结合粘土的粘附末端的末端官能化树枝状大分子的非共价键形成。
