Thiele Sophia, Plummer Christopher J G, Piveteau Laura, Frauenrath Holger
École Polytechnique Fédérale de Lausanne (EPFL) Institute of Materials, Lausanne, Switzerland.
École Polytechnique Fédérale de Lausanne (EPFL) Nuclear Magnetic Resonance Platform, Lausanne, Switzerland.
Commun Chem. 2025 Jul 28;8(1):217. doi: 10.1038/s42004-025-01597-w.
The dynamic nature of supramolecular networks of telechelic polymers offers new avenues for the design of novel materials with enhanced melt strength and extensibility, increased energy at break, or self-healing properties. However, monitoring the kinetics of the underlying molecular-level scission-reaggregation events remains challenging, particularly in high-molar-mass polymers in the bulk state. Here, we employ solid-state H NMR spectroscopy relaxation dispersion experiments to investigate the aggregation-scission dynamics in poly(ε-caprolactone) modified with oligopeptide end groups that form one-dimensional hydrogen-bonded aggregates. We have successfully determined the timescale of end-group dissociation directly and independently of any relaxation of the polymer segments at different temperatures in the bulk semi-crystalline and melt state. This site-specific, non-destructive method is applicable to entangled, high-molar-mass polymers without chemical modifications or modeling, provides critical insight into the dynamics of supramolecular networks in the bulk state, and promises to be a valuable tool for the directed development of next-generation functional materials.
遥爪聚合物超分子网络的动态特性为设计具有增强熔体强度和可拉伸性、增加断裂能或自愈性能的新型材料提供了新途径。然而，监测潜在分子水平的断裂-重新聚集事件的动力学仍然具有挑战性，特别是在本体状态的高摩尔质量聚合物中。在这里，我们采用固态氢核磁共振光谱弛豫色散实验来研究用形成一维氢键聚集体的寡肽端基修饰的聚（ε-己内酯）中的聚集-断裂动力学。我们已经成功地直接且独立于本体半结晶和熔体状态下不同温度下聚合物链段的任何弛豫，确定了端基解离的时间尺度。这种位点特异性的非破坏性方法适用于未经化学修饰或建模的缠结高摩尔质量聚合物，能深入了解本体状态下超分子网络的动力学，并有望成为定向开发下一代功能材料的宝贵工具。
