State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry , Jilin University , Changchun 130012 , P. R. China.
National Engineering Research Center for Colloidal Materials, School of Chemistry and Chemical Engineering , Shandong University , Jinan 250100 , P. R. China.
ACS Appl Mater Interfaces. 2018 Sep 12;10(36):30716-30722. doi: 10.1021/acsami.8b10277. Epub 2018 Aug 28.
The development of efficient methods to trigger high mobility of polymer chains to migrate across the damaged areas is key for healing wide damages in intrinsic healable polymeric films deposited on solid substrates. Herein, we establish a facile strategy for the fabrication of polymeric films with a superhigh healing capability by controlling the conformational transition of the polymer chains in polymeric films. The alternately spin-coated poly(acrylic acid) (PAA)/polyurethane (PU) films with coiled PU can heal cuts with a width of 6 times the thickness of the PAA/PU films in the presence of ethanol. In contrast, the same PAA/PU films with stretched PU or those films with coiled PU but without conformational transition from a coiled state to a stretched state fail to heal cuts. The conformational transition of PU from a coiled state to a stretched state in PAA/PU films triggered by ethanol enables a long-distance migration of PAA and PU polymers to heal wide mechanical damages.
开发高效的方法来触发聚合物链的高迁移率，以跨越受损区域，对于修复内在可修复聚合物薄膜在固体基底上的大面积损伤至关重要。在此，我们通过控制聚合物薄膜中聚合物链的构象转变，建立了一种制备具有超高修复能力的聚合物薄膜的简便策略。交替旋涂的具有卷曲 PU 的聚（丙烯酸）（PAA）/聚氨酯（PU）薄膜在存在乙醇的情况下可以修复宽度为 PAA/PU 薄膜厚度 6 倍的切口。相比之下，具有拉伸 PU 的相同 PAA/PU 薄膜或具有卷曲 PU 但没有从卷曲状态到拉伸状态的构象转变的薄膜无法修复切口。乙醇引发的 PAA/PU 薄膜中 PU 从卷曲状态到拉伸状态的构象转变，使 PAA 和 PU 聚合物能够远距离迁移，从而修复大面积的机械损伤。
