Polymeric single‐chain nanoparticles (SCNPs) are soft nano‐objects synthesized by intramolecular crosslinking of isolated single polymer chains. Syntheses of such SCNPs usually need to be performed in a dilute solution. In such a condition, the bonding probability of the two active crosslinking units at a short contour distance along the chain backbone is much higher than those which are far away from each other. Such a reaction condition often results in local spheroidization and, therefore, the formation of loosely packed structures. How to inhibit the local spheroidization and improve the compactness of SCNPs is thus a major challenge for the syntheses of SCNPs. In this study, computer simulations are performed and the fact that a precollapse of the polymer chain conformation in a cosolvent condition can largely improve the probability of the crosslinking reactions at large contour distances is demonstrated, favoring the formations of closely packed globular structures. As a result, the formed SCNPs can be more spherical and have higher compactness than those fabricated in ultradilute good solvent solution in a conventional way. It is believed this simulation work can provide a insight into the effective syntheses of SCNPs with spherical conformations and high compactness.

中文翻译：

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共溶剂条件下高致密性聚合物单链纳米粒子的合成：计算机模拟研究

聚合物单链纳米粒子（SCNP）是通过孤立的单个聚合物链的分子内交联合成的软纳米物体。通常需要在稀溶液中进行此类SCNP的合成。在这样的条件下，两个活性交联单元在沿着链主链的短轮廓距离处的键合概率远高于彼此远离的那些。这种反应条件常常导致局部球化，因此形成松散堆积的结构。因此，如何抑制局部球化并提高SCNP的紧密度是SCNP合成的主要挑战。在这个研究中，进行了计算机模拟，并证明了在助溶剂条件下聚合物链构象的预崩解可以大大提高在较大轮廓距离处发生交联反应的可能性，这有利于紧密堆积的球状结构的形成。结果，与以常规方式在超稀良溶剂溶液中制备的那些相比，所形成的SCNP可以更球形并且具有更高的致密性。可以相信，该模拟工作可以提供对球形构型和高致密性的SCNP的有效合成的见解。与以常规方式在超稀良溶剂溶液中制备的那些相比，所形成的SCNP可以更球形且具有更高的致密性。可以相信，该模拟工作可以提供对球形构型和高致密性的SCNP的有效合成的见解。与以常规方式在超稀良溶剂溶液中制备的那些相比，所形成的SCNP可以更球形且具有更高的致密性。可以相信，该模拟工作可以提供对球形构型和高致密性的SCNP的有效合成的见解。