Department of Mechanical Engineering, Louisiana State University, Baton Rouge, LA 70803, USA.
J R Soc Interface. 2012 Dec 7;9(77):3279-87. doi: 10.1098/rsif.2012.0409. Epub 2012 Aug 15.
Severe wounds in biological systems such as human skin cannot heal themselves, unless they are first stitched together. Healing of macroscopic damage in thermoset polymer composites faces a similar challenge. Stimuli-responsive shape-changing polymeric fibres with outstanding mechanical properties embedded in polymers may be able to close macro-cracks automatically upon stimulation such as heating. Here, a stimuli-responsive fibre (SRF) with outstanding mechanical properties and supercontraction capability was fabricated for the purpose of healing macroscopic damage. The SRFs and thermoplastic particles (TPs) were incorporated into regular thermosetting epoxy for repeatedly healing macroscopic damages. The system works by mimicking self-healing of biological systems such as human skin, close (stitch) then heal, i.e. close the macroscopic crack through the thermal-induced supercontraction of the SRFs, and bond the closed crack through melting and diffusing of TPs at the crack interface. The healing efficiency determined using tapered double-cantilever beam specimens was 94 per cent. The self-healing process was reasonably repeatable.
生物系统（如人类皮肤）中的严重伤口无法自行愈合，除非先将它们缝合在一起。热固性聚合物复合材料中的宏观损伤的愈合也面临着类似的挑战。在聚合物中嵌入具有出色机械性能和超收缩能力的刺激响应形状记忆纤维，可能能够在受到刺激（如加热）时自动闭合宏观裂缝。在这里，为了修复宏观损伤，制备了一种具有出色机械性能和超收缩能力的刺激响应纤维 (SRF)。将 SRF 和热塑性颗粒 (TP) 掺入常规热固性环氧树脂中，以重复修复宏观损伤。该系统的工作原理是模仿人类皮肤等生物系统的自我修复，即通过 SRF 的热诱导超收缩来闭合宏观裂缝，并通过 TPs 在裂缝界面处的熔融和扩散来粘合闭合的裂缝。使用锥形双悬臂梁试样确定的愈合效率为 94%。自修复过程具有较好的重现性。
