当一个橡胶带断裂后，我们的办法是换一个新的。但本期Nature上描述的一种引人瞩目的新材料的行为却很不相同。这种新材料由包含三种不同官能团的分子组成，三个官能团形成多个氢键，这些分子一起形成一种“超分子橡胶”，既包含链形结构，又包含交联结构。这个体系具有橡胶一样的行为，即当被拉长到其原始长度几倍的长度时，它们能够恢复到原始长度。与由大分子构成的传统橡胶相比，这种材料在断裂后，如将断面在室温下放到一起，它们还能自我愈合。这种新材料可以用简单的成分（脂肪酸和尿素）来合成，而一旦合成之后，再加工就比较容易了。按照其目前的形势，这种超分子橡胶在压力下恢复较慢，在应力作用下会发生“蠕变”，但通过调整起始组分，可以获得一系列不同性能。
生物谷推荐原始出处:
Nature 451, 977-980 (21 February 2008) | doi:10.1038/nature06669; Received 14 August 2007; Accepted 11 January 2008
Self-healing and thermoreversible rubber from supramolecular assembly
Philippe Cordier, Franois Tournilhac, Corinne Soulié-Ziakovic & Ludwik Leibler
Matière Molle et Chimie, UMR 7167 CNRS-ESPCI, Ecole Supérieure de Physique et Chimie Industrielles, 10 rue Vauquelin, 75005 Paris, France
Correspondence to: Ludwik Leibler1 Correspondence and requests for materials should be addressed to L.L. (Email: ludwik.leibler@espci.fr).
Top of pageRubbers exhibit enormous extensibility up to several hundred per cent, compared with a few per cent for ordinary solids, and have the ability to recover their original shape and dimensions on release of stress. Rubber elasticity is a property of macromolecules that are either covalently cross-linked or connected in a network by physical associations such as small glassy or crystalline domains, ionic aggregates6 or multiple hydrogen bonds. Covalent cross-links or strong physical associations prevent flow and creep. Here we design and synthesize molecules that associate together to form both chains and cross-links via hydrogen bonds. The system shows recoverable extensibility up to several hundred per cent and little creep under load. In striking contrast to conventional cross-linked or thermoreversible rubbers made of macromolecules, these systems, when broken or cut, can be simply repaired by bringing together fractured surfaces to self-heal at room temperature. Repaired samples recuperate their enormous extensibility. The process of breaking and healing can be repeated many times. These materials can be easily processed, re-used and recycled. Their unique self-repairing properties, the simplicity of their synthesis, their availability from renewable resources and the low cost of raw ingredients (fatty acids and urea) bode well for future applications.
