Lower disorder-to-order transition (LDOT) phase behavior is seldom observed in block copolymers (BCPs). Design of LDOT BCPs is important for broadening the applications and improving the high temperature properties of BCPs. In this work, the LDOT phase behavior was first achieved in the strongly interacting BCPs consisting of poly(ethylene oxide) (PEO) and poly(ionic liquid) (PIL) blocks (EO_m-b-(IL-X)_n, X: counterion) by introducing two extra strong forces (hydrogen-bonding and Coulombic interaction) with different temperature dependences. It is also found that the LDOT phase behavior of the EO_m-b-(IL-X)_n BCPs can be regulated by molecular weight (related to mixing entropy), counterion, and salt doping. Increasing counterion size and salt content shifts the disorder-to-order transition temperature (T_DOT) to higher temperature, whereas a higher molecular weight leads to a lower T_DOT. Based on our findings, some general rules for design of LDOT phase behavior in the strongly interacting BCPs were proposed. Moreover, the conductivity of the EO_m-b-(IL-X)_n BCPs was correlated with the LDOT phase behavior. A remarkable increase in conductivity after LDOT, i.e., a thermo-activated transition, is observed for the EO_m-b-(IL-X)_n BCPs, which can be attributed to the cooperative effects of temperature rising and LDOT.

中文翻译：

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强相互作用嵌段共聚物中低序无序过渡行为的设计与调控

在嵌段共聚物（BCP）中很少观察到较低的无序转变（LDOT）相行为。LDOT BCP的设计对于拓宽BCP的应用范围和改善其高温性能非常重要。在这项工作中，LDOT相行为首先在由聚环氧乙烷（PEO）和聚离子液体（PIL）嵌段（EO _m - b-（IL-X）_n，X ：抗衡离子），通过引入两个具有不同温度依赖性的超强力（氢键和库仑相互作用）。还发现EO _m - b-（IL-X）_n的LDOT相行为BCP可以通过分子量（与混合熵有关），抗衡离子和盐掺杂来调节。抗衡离子尺寸和盐含量的增加将无序转变温度（T _DOT）移至更高的温度，而分子量越高则T _DOT越低。根据我们的发现，提出了一些在强烈相互作用的BCP中设计LDOT相行为的一般规则。此外，EO _m - b-（IL-X）_n BCP的电导率与LDOT相行为有关。对于EO _m - b-（IL-X）_n，观察到LDOT之后电导率显着增加，即热激活跃迁。 BCP，可以归因于温度上升和LDOT的协同作用。