Tan Zhengping, Ban Soohyun, Ahn Younghyeon, Ku Kang Hee, Kim Bumjoon J
Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) Daejeon 34141 Republic of Korea
School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST) Ulsan 44919 Republic of Korea
Chem Sci. 2025 Mar 8;16(15):6265-6272. doi: 10.1039/d5sc00259a. eCollection 2025 Apr 9.
Block copolymer (BCP) particles with tailored shapes and nanostructures hold promise for applications in cell adhesion, photonic system, and energy storage due to their unique optical and rheological properties. Conventional approaches relying on surfactant-mediated self-assembly often limit particle geometries to simple structures. Herein, we present a versatile approach to expand the morphology of poly(styrene--2-vinylpyridine) (PS--P2VP) BCP particles through the incorporation of 9-bromononanoic acid (BNA), a bifunctional additive that facilitates synergistic quaternization and protonation. Increasing the BNA-to-2VP molar ratio enhances P2VP hydrophilicity and decreases the pH value, driving dramatic shape transitions from onion-like spheres to tulip bulbs, ellipsoids, discs, and Janus cups. This morphological diversity is attributed to synergetic interfacial instability-driven water infiltration and pH-induced repulsion of protonated P2VP chains. Additives with a single functional group, however, yield limited morphologies, such as tulip bulbs or onion-like spheres. Notably, Janus cups fabricated this strategy exhibit selective cargo-loading capabilities, highlighting the importance of precise control over the internal composition and structure of BCP particles.
具有定制形状和纳米结构的嵌段共聚物（BCP）颗粒因其独特的光学和流变学性质，在细胞粘附、光子系统和能量存储等应用领域具有广阔前景。传统的依靠表面活性剂介导的自组装方法通常将颗粒几何形状限制为简单结构。在此，我们提出了一种通用方法，通过引入9-溴壬酸（BNA）来扩展聚（苯乙烯-2-乙烯基吡啶）（PS-P2VP）BCP颗粒的形态，BNA是一种双功能添加剂，可促进协同季铵化和质子化。增加BNA与2VP的摩尔比可增强P2VP亲水性并降低pH值，促使颗粒形状从洋葱状球体急剧转变为郁金香球茎、椭球体、圆盘和双面杯。这种形态多样性归因于协同界面不稳定性驱动的水渗透以及pH诱导的质子化P2VP链的排斥作用。然而，具有单一官能团的添加剂会产生有限的形态，如郁金香球茎或洋葱状球体。值得注意的是，通过这种策略制备的双面杯表现出选择性载物能力，突出了精确控制BCP颗粒内部组成和结构的重要性。
