This work quantitatively explores the effect of chain length heterogeneity on self-assembly behaviors of block copolymer, focusing on the narrow distribution region. A library of discrete diblock copolymers consisting of oligo dimethylsiloxane (oDMS) and oligo lactic acid (oLA) blocks were modularly prepared with one monomer difference in composition, which form highly ordered nanostructures at room temperature. The molecular weight distribution of the oLA block was then precisely modulated through a reconstruction approach, achieving an absolute control on chain length heterogeneity. By meticulously tuning the breadth and symmetry of the distribution profile, the lattice dimension of the assembled nanostructure significantly expands, while no appreciable difference on the phase stability was observed. This work provides an explicit access to block copolymers with narrow dispersity that are not possible through conventional chemical approach, revealing the critical contribution of dispersity on self-assembly and bridging the existing gaps between experiments and theories.

这项工作定量研究了链长不均一性对嵌段共聚物自组装行为的影响，重点是狭窄的分布区域。模块化制备了由低聚二甲基硅氧烷（o DMS）和低聚乳酸（o LA）嵌段组成的离散二嵌段共聚物库，其中单体组成不同，在室温下形成高度有序的纳米结构。o的分子量分布然后，通过重构方法对LA嵌段进行精确调制，从而实现对链长异质性的绝对控制。通过精心调整分布图的宽度和对称性，组装的纳米结构的晶格尺寸显着扩大，而在相稳定性上没有发现明显的差异。这项工作为通过常规化学方法不可能获得的窄分散性嵌段共聚物提供了明确的途径，揭示了分散性对自组装的关键贡献，并弥合了实验和理论之间的现有差距。