Polymer networks generally consist of an ensemble of single chains. However, understanding how chain conformation affects the structure and properties of polymer networks remains a challenge for optimizing their functionality. Here, we present the fabrication and comparative study of a polymer network composed of collapsed self-entangled chains (intrachain entangled network) and a standard polymer network in which random-coil chains are entangled with each other (interchain entangled network). For poly(methyl methacrylate) thin films composed of these networks, we coupled solvent vapor swelling and single-molecule tracking techniques to examine the anomalies in the dynamics of a small-molecular probe included in the system. We demonstrate that when compared to the interchain entangled network the intrachain one exhibits a more substantial structural heterogeneity, particularly under highly crowded conditions. This network also exhibits physical compactness, which keeps the heterogeneous network structure frozen over time and impedes network plasticization through solvent uptake by the film.

中文翻译：

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链构象对聚合物网络结构异质性的影响

聚合物网络通常由一组单链组成。然而，了解链构象如何影响聚合物网络的结构和性质仍然是优化其功能的挑战。在这里，我们介绍了由折叠的自纠缠链（链内纠缠网络）和随机螺旋链相互纠缠的标准聚合物网络（链间纠缠网络）组成的聚合物网络的制造和比较研究。对于由这些网络组成的聚（甲基丙烯酸甲酯）薄膜，我们结合了溶剂蒸气溶胀和单分子跟踪技术来检查系统中包含的小分子探针的动力学异常。我们证明，与链间纠缠网络相比，链内网络表现出更显着的结构异质性，特别是在高度拥挤的条件下。该网络还表现出物理致密性，使异质网络结构随着时间的推移保持冻结，并通过薄膜吸收溶剂阻碍网络塑化。