The microscopic mechanism accounting for the self-healing attribute of aromatic ionene-forming hydrogels derived from 1,4-diazabicyclo [2.2.2]octane (DABCO) and N,N’-(x-phenylene)dibenzamide (x = ortho-/meta-/para-) is unknown. Interestingly, the self-healing property of such DABCO-containing hydrogels is largely dependent on the polymer topology, the ortho ionene being the only self-healable without adding oppositely charged species. In this work, Molecular Dynamics (MD) simulations have been conducted to evaluate the influence of the topology on ionene···ionene and ionene··water interactions, as well as their effect on the self-healing behavior. For this purpose, destabilized and structurally damaged models were produced for ionene hydrogels with ortho, meta and para topologies and used as starting geometries for simulations. These models were allowed to evolve without any restriction during MD production runs and, subsequently, the temporal evolution of ionene···ionene and water···ionene interactions was examined. Analysis of the results indicated that the ortho-isomer rapidly forms unique interactions that are not detected for other two isomers. Thus, in addition to the interactions also identified for the meta-and para-ionenes, the ortho-isomer exhibits the formation of strong intermolecular three-centered (N–)H⋯O (=C)⋯H (–N) hydrogen bonds, intramolecular planar sandwich π-π stacking interactions and Cl⁻···N⁺ electrostatic interactions. Furthermore, the amount of intermolecular π-π stacking interactions and the strength of water···polymer interaction are also influenced by the topology, favoring the stabilization of the ortho-ionene reconstituted hydrogels. Overall, the arrangement of the functional groups in the ortho topology favors the formation of more types of ionene···ionene interactions, as well as stronger interactions, than in the meta and para topologies.

微观机理解释了由1,4-二氮杂双环[2.2.2]辛烷（DABCO）和N，N '-（x-亚苯基）二苯甲酰胺（x  = 邻位-/ meta- / para-）未知。有趣的是，这种含DABCO的水凝胶的自愈特性在很大程度上取决于聚合物的拓扑结构，即邻位紫罗烯是唯一可自我修复而不添加带相反电荷的物质。在这项工作中，进行了分子动力学（MD）仿真，以评估拓扑结构对紫罗兰···紫罗兰和紫罗兰···水相互作用的影响，以及它们对自愈性能的影响。为此，针对具有邻位，间位和对位拓扑结构的紫罗兰水凝胶生产了不稳定和结构受损的模型，并将其用作模拟的起始几何形状。允许这些模型在MD生产过程中不受任何限制地演化，随后，研究了紫罗兰···紫罗兰和水···紫罗兰的相互作用的时间演化。分析结果表明，邻位-异构体快速形成独特的相互作用，这是其他两个异构体无法检测到的。因此，除了还确定了间-和对-紫罗烯的相互作用外，邻位异构体还表现出强分子间三中心（N–）H⋯O（= C）⋯H（–N）氢键的形成。分子内的平面三明治π-π堆积相互作用和Cl ^- ...ñ ⁺静电相互作用。此外，分子间π-π堆积相互作用的量和水···聚合物相互作用的强度也受拓扑影响，有利于邻紫罗兰烯重构的水凝胶的稳定化。总体而言，邻位官能团的排列与间位拓扑和对位拓扑相比，拓扑结构支持形成更多类型的紫罗兰···紫罗兰相互作用以及更强的相互作用。