Abstract Great progress has been made in the research of self-healing materials in recent decades, however, there are still great challenges in achieving high mechanical strength and wide scratch healing simultaneously. Herein, a novel polyurethane elastomer (PUDA) containing polycaprolactone (PCL) soft segments and Diels-Alder (DA) adducting structure was specially designed and synthesized. The experimental results show that the PUDA elastomer after being trained not only had ultrahigh mechanical strength, but also had satisfactory ability in healing of wide scratches. It was found that the elastomer displayed a high tensile strength up to 32.88 MPa, which is unprecedented when compared to those reported self-healing elastomers. The PUDA elastomer material also had excellent healing ability towards wide scratches: an 80-μm-wide scratch could be completely healed after heating at 110°C for 6 min. Furthermore, the elastomer material could also attain more than 100 % recovery of mechanical strength, with its recovered tensile strength reaching up to 34.58 MPa. The developed PUDA elastomer demonstrates quite promising perspective in material science and engineering field, especially for the protection of surface coating.

中文翻译：

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一种具有超强机械强度和优异宽划痕自愈性能的新型聚氨酯弹性体

摘要 近几十年来，自修复材料的研究取得了很大进展，但要同时实现高机械强度和广泛的划痕愈合仍存在巨大挑战。在此，专门设计并合成了一种含有聚己内酯（PCL）软链段和狄尔斯-阿尔德（DA）加成结构的新型聚氨酯弹性体（PUDA）。实验结果表明，经过训练的PUDA弹性体不仅具有超高的机械强度，而且对宽划痕的愈合能力也令人满意。发现该弹性体显示出高达 32.88 MPa 的高拉伸强度，与报道的自修复弹性体相比，这是前所未有的。PUDA 弹性体材料对宽大的划痕也具有出色的愈合能力：在 110°C 加热 6 分钟后，80 微米宽的划痕可以完全愈合。此外，弹性体材料还可以获得超过 100% 的机械强度恢复，其恢复拉伸强度高达 34.58 MPa。开发的PUDA弹性体在材料科学和工程领域，特别是在表面涂层的保护方面表现出非常有前景的前景。