Lindsay Aaron P, Lewis Ronald M, Lee Bongjoon, Peterson Austin J, Lodge Timothy P, Bates Frank S
ACS Macro Lett. 2020 Feb 18;9(2):197-203. doi: 10.1021/acsmacrolett.9b01026. Epub 2020 Jan 27.
A renewed focus on the phase behavior of nominally single-component, compositionally asymmetric diblock copolymers has revealed a host of previously unanticipated Frank-Kasper (FK) and quasicrystalline phases. However, these periodic and aperiodic particle packings have thus far only been reported in low molecular weight, highly conformationally asymmetric diblock copolymers, leaving researchers with a relatively small library of polymers in which these phases can be studied. In this work, we report on a simple approach to access these morphologies: blending two diblock copolymers with the same corona block length and varied core block lengths. Compositionally symmetric and asymmetric polystyrene--1,4-polybutadiene (SB) diblock copolymers with constant corona block lengths were blended together and shown via small-angle X-ray scattering and transmission electron microscopy to order into the FK A15 and σ phases, as well as a dodecagonal quasicrystal, providing a route to various particle packings in high molecular weight diblock copolymer melts.
对名义上单组分、组成不对称的二嵌段共聚物相行为的重新关注揭示了许多以前未预料到的弗兰克-卡斯帕（FK）相和准晶相。然而，迄今为止，这些周期性和非周期性的粒子堆积仅在低分子量、高度构象不对称的二嵌段共聚物中被报道过，这使得研究人员可用于研究这些相的聚合物库相对较小。在这项工作中，我们报告了一种获得这些形态的简单方法：将两种具有相同冠链段长度和不同核链段长度的二嵌段共聚物共混。将具有恒定冠链段长度的组成对称和不对称的聚苯乙烯-1,4-聚丁二烯（SB）二嵌段共聚物共混在一起，并通过小角X射线散射和透射电子显微镜显示它们有序排列成FK A15相和σ相，以及一个十二边形准晶，为在高分子量二嵌段共聚物熔体中形成各种粒子堆积提供了一条途径。
