Department of Chemistry, University of Victoria, Victoria, British Columbia, Canada.
Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China.
Nat Mater. 2023 Jun;22(6):786-792. doi: 10.1038/s41563-023-01559-4. Epub 2023 May 22.
Seeded growth of crystallizable block copolymers and π-stacking molecular amphiphiles in solution using living crystallization-driven self-assembly is an emerging route to fabricate uniform one-dimensional and two-dimensional core-shell micellar nanoparticles of controlled size with a range of potential applications. Although experimental evidence indicates that the crystalline core of these nanomaterials is highly ordered, a direct observation of their crystal lattice has not been successful. Here we report the high-resolution cryo-transmission electron microscopy studies of vitrified solutions of nanofibres made from a crystalline core of poly(ferrocenyldimethylsilane) (PFS) and a corona of polysiloxane grafted with 4-vinylpyridine groups. These studies show that poly(ferrocenyldimethylsilane) chains pack in an 8-nm-diameter core lattice with two-dimensional pseudo-hexagonal symmetry that is coated by a 27 nm 4-vinylpyridine corona with a 3.5 nm distance between each 4-vinylpyridine strand. We combine this structural information with a molecular modelling analysis to propose a detailed molecular model for solvated poly(ferrocenyldimethylsilane)-b-4-vinylpyridine nanofibres.
使用活的结晶驱动自组装在溶液中种植结晶性嵌段共聚物和π堆积分子两亲体是制造具有各种潜在应用的均匀一维和二维核壳胶束纳米粒子的一种新兴途径，其具有受控的尺寸。尽管实验证据表明这些纳米材料的结晶核高度有序，但尚未成功直接观察到它们的晶格。在这里，我们报告了使用聚（二甲基硅烷）（PFS）的结晶核和接枝有 4-乙烯基吡啶基团的聚硅氧烷冠的纳米纤维的玻璃化溶液的高分辨率冷冻透射电子显微镜研究。这些研究表明，聚（二甲基硅烷）链在具有二维拟六方对称性的 8nm 直径核晶格中堆积，其被 27nm 的 4-乙烯基吡啶冠层涂覆，每个 4-乙烯基吡啶链之间的距离为 3.5nm。我们将此结构信息与分子建模分析相结合，提出了溶剂化聚（二甲基硅烷）-b-4-乙烯基吡啶纳米纤维的详细分子模型。
