Ring-and-Lock Interactions in Self-Healable Styrenic Copolymers
Ring-and-Lock Interactions in Self-Healable Styrenic Copolymers
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DOI：
10.1021/jacs.3c01199
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发表时间：
2023-04-17
影响因子：
15
通讯作者：
Urban, Marek W.
中科院分区：
文献类型：
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作者：
Gaikwad, Samruddhi;Urban, Marek W.
商品共聚物提供了许多有用的应用，其耐久性对于维持所需功能和保持可持续性至关重要。这些研究表明，当单体摩尔比在 45:55-53:47 范围内时，主要是苯乙烯/丙烯酸正丁酯 [p(Sty/nBA)] 交替共聚物在无需外部干预的情况下进行自修复。这种行为归因于脂肪族 nBA 侧基之间有利的链间相互作用，这些侧基被芳香环夹在中间，形成由 pi-sigma-pi (pi-sigma-pi) 相互作用驱动的环锁缔合。在分子动力学 (MD) 模拟结合光谱和热机械分析的指导下，芳香环的 pi 轨道和脂肪族侧基的 sigma 成分之间的环锁链间范德华力负责自修复。尽管这些相互作用在生物系统（蛋白质、核酸、脂质和多糖）中经常发生，但软酸脂肪族电子和软碱芳香族电子之间这些很大程度上未经探索的弱而普遍的分子力可能是开发具有可持续特性的聚合物材料的宝贵资产。
Commodity copolymers offer many useful applica-tions, and their durability is critical in maintaining desired functions and retaining sustainability. These studies show that primarily alternating styrene/n-butyl acrylate [p(Sty/nBA)] co-polymers self-heal without external intervention when monomer molar ratios are within the 45:55-53:47 range. This behavior is attributed to the favorable interchain interactions between aliphatic nBA side groups being sandwiched by aromatic rings forming ring-and-lock associations driven by pi-sigma-pi (pi-sigma-pi) inter-actions. Guided by molecular dynamics (MD) simulations combined with spectroscopic and thermomechanical analysis, the ring-and-lock interchain van der Waals forces between pi orbitals of aromatic rings and sigma components of aliphatic side groups are responsible for self-healing. Despite the frequent occurrence of these interactions in biological systems (proteins, nucleic acids, lipids, and polysaccharides), these largely unexplored weak and ubiquitous molecular forces between the soft acid aliphatic and soft base aromatic electrons may be valuable assets in the development of polymeric materials with sustainable properties.