A self-healing elastomer based on an intrinsic non-covalent cross-linking mechanism
A self-healing elastomer based on an intrinsic non-covalent cross-linking mechanism
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基于固有非共价交联机制的自修复弹性体
DOI：
10.1039/c9ta03775f
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发表时间：
2019-07-07
影响因子：
11.9
通讯作者：
Luo, Zhenyang
中科院分区：
文献类型：
--
作者：
Chen, Jun;Li, Fanzhu;Luo, Zhenyang
报道了一种基于内在动力学非共价键（货车德瓦耳斯键和氢键）自愈合的聚氨酯（脲）弹性体的合成和综合研究。动态非共价键包括氢键和货车范德华力。与以前的方法不同，在以前的方法中，氢键自修复材料在末端或支链聚乙烯上引入了密集的四重氢键。以聚碳酸亚丙酯（PPC）二醇作为聚氨酯（脲）材料的软段，其主链上大量的羰基提供了较强的货车范德华力;通过氨基甲酸酯键、脲键和PPC上的羰基形成氢键。研究了自愈合聚氨酯（脲）弹性体的力学性能和愈合效率。原位温度依赖的红外和低场核磁共振（LNMR）测量结合分子动力学模拟研究的自我修复机制。对自修复聚氨酯的研究结果表明，氢键和货车范德华力之间的动态交联是材料自修复能力的基本驱动力，温度是影响氢键和货车范德华力的关键因素。研究了晶化对材料自修复能力的影响。分子动力学模拟结果还显示了不同温度下货车范德华力和氢键之间的相互作用。
Synthesis and comprehensive examination of a polyurethane (urea) elastomer that self-heals based on intrinsic dynamic non-covalent bonds (van der Waals and hydrogen) are reported. The dynamic non-covalent bonds include hydrogen bonds and van der Waals forces. The difference in the previous approach in which hydrogen bond self-healing materials introduced dense quadruple hydrogen bonds at the ends or branched chains poly(propylene carbonate) (PPC) diol was used as the soft segment of the polyurethane (urea) material, and strong van der Waals forces were provided by the large number of carbonyl groups in its main chain; hydrogen bonds were formed by urethane bonds, urea bonds, and the carbonyl groups on PPC. The mechanical properties and healing efficiency of the self-healing polyurethane (urea) elastomer were studied. In situ temperature-dependent infrared and low-field nuclear magnetic resonance (LNMR) measurements were combined with molecular dynamics simulations to investigate the self-healing mechanisms. The results of the studies on the self-healing polyurethane demonstrate that the dynamic cross-linking between hydrogen bonds and van der Waals forces is the basic driving force for the self-healing ability of the material, and temperature is the key factor that affects hydrogen bonding and van der Waals forces. The effect of crystallization on the self-healing ability of the material was also studied. The molecular dynamics simulation results also demonstrate interplay between van der Waals forces and hydrogen bonds at different temperatures.