當(dāng)一個橡膠帶斷裂后,，我們的辦法是換一個新的,。但本期Nature上描述的一種引人矚目的新材料的行為卻很不相同,。這種新材料由包含三種不同官能團(tuán)的分子組成,，三個官能團(tuán)形成多個氫鍵,，這些分子一起形成一種“超分子橡膠”,，既包含鏈形結(jié)構(gòu)，又包含交聯(lián)結(jié)構(gòu),。這個體系具有橡膠一樣的行為,，即當(dāng)被拉長到其原始長度幾倍的長度時，它們能夠恢復(fù)到原始長度,。與由大分子構(gòu)成的傳統(tǒng)橡膠相比,，這種材料在斷裂后，如將斷面在室溫下放到一起,，它們還能自我愈合,。這種新材料可以用簡單的成分（脂肪酸和尿素）來合成，而一旦合成之后,，再加工就比較容易了,。按照其目前的形勢，這種超分子橡膠在壓力下恢復(fù)較慢,，在應(yīng)力作用下會發(fā)生“蠕變”,，但通過調(diào)整起始組分，可以獲得一系列不同性能,。
生物谷推薦原始出處:
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: [email protected]).
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.
