Highly dense polymer chains were formed through coupling cyclic polymeric units in a sequence controlled manner. It was found that as the number of cyclic units increased the compactness substantially increased in a good solvent to a limiting value after only 12 units. This limiting value was close to that of a linear polymer chain in a θ solvent, in which polymer segment interactions with solvent are minimized. This remarkable result suggests that the unique architecture of the cyclic structure plays an important role to significantly change the polymer conformation and remain soluble in solution, which circumvents the need for cross-linking. The insight found in this work provides a physical mechanism as to why Nature uses cyclic structures in proteins to confer stability and the compacting of DNA strands to induce chromosome territories.

中文翻译：

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密集堆积的多环聚合物

通过以顺序控制的方式偶联环状聚合物单元形成高密度聚合物链。发现随着环状单元数量的增加，仅在 12 个单元之后，在良溶剂中紧密度显着增加至极限值。该极限值接近 θ 溶剂中的线性聚合物链的极限值，其中聚合物链段与溶剂的相互作用最小化。这一显着的结果表明，环状结构的独特结构在显着改变聚合物构象并保持可溶于溶液中起着重要作用，从而避免了交联的需要。在这项工作中发现的见解提供了一种物理机制，解释了自然为什么使用蛋白质中的环状结构来赋予稳定性和 DNA 链的压实以诱导染色体区域。