School of Physics, Key Laboratory of Functional Polymer Materials of Ministry of Education, and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin, 300071, China.
Soft Matter. 2021 Apr 28;17(16):4434-4444. doi: 10.1039/d1sm00103e.
Achiral block copolymers can self-assemble into helical structures when confined inside a cylindrical nanopore. However, controlling the chirality and the number of strands of helices is challenging. We present our simulation results of the influence of a chiral patch added to the confining nanopore on the structures and chirality of helices self-assembled from achiral cylinder-forming diblock copolymers under the confinement. Our results indicate that, when the designed patch is of proper geometry, it can induce the formation of helical structures and exhibit good control over their chirality. The bottom surface of the patch can induce the formation of a characteristic local structure near and parallel to it. It is the characteristic local structure that directs the formation of helices and of their chirality consistent with that of the patch. A large patch angle or the top/bottom surface of a weakly selective pore promotes the formation of double-helices compared to single-helices by enlarging the pitch of the helices near the patch or through the entropic attraction of the top surface of the pore to the minority blocks.
手性嵌段共聚物在圆柱纳米孔内受限时可以自组装成螺旋结构。然而，控制螺旋的手性和链数是具有挑战性的。我们提出了在受限条件下，手性补丁添加到限制纳米孔对由非手性圆柱形成二嵌段共聚物自组装形成的螺旋结构和手性的影响的模拟结果。我们的结果表明，当设计的补丁具有适当的几何形状时，它可以诱导螺旋结构的形成，并对其手性具有良好的控制。补丁的底部表面可以在其附近并与其平行的位置诱导形成特征局部结构。正是该特征局部结构指导了螺旋的形成及其与补丁一致的手性。较大的补丁角度或较弱选择性孔的顶/底面通过增大补丁附近螺旋的螺距或通过孔顶面对少数嵌段的熵吸引力，促进了双螺旋的形成，而不是单螺旋的形成。
