Shi Ling-Ying, Liao Fen, Cheng Li-Chen, Lee Sangho, Ran Rong, Shen Zhihao, Ross Caroline A
College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China.
Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
ACS Macro Lett. 2019 Jul 16;8(7):852-858. doi: 10.1021/acsmacrolett.9b00283. Epub 2019 Jun 25.
The self-assembly of multiblock copolymers generates diverse hierarchical nanostructures and greatly extends the range of microdomain geometries beyond those produced by diblock copolymers. We report the synthesis of a conformationally asymmetric ABC triblock terpolymer in which the end blocks are a mesogen-jacketed liquid crystalline polymer and poly(dimethylsiloxane), respectively, and its self-assembly under mixed solvent vapor annealing forms a range of sphere, cylinder, and perforated lamellar core-shell morphologies, as well as stacked multilevel structures. Sub-7 nm diameter SiO nanopatterns were generated by selective plasma etching of the small volume fraction Si-containing core block giving a line/space ratio of ∼1:4. Moreover, the conformational asymmetry of this terpolymer leads to zigzag cylinders on a flat substrate and stable cylinder alignment transverse to template sidewalls within lithographically patterned trenches.
多嵌段共聚物的自组装产生了多样的分级纳米结构，并极大地扩展了微区几何形状的范围，超出了二嵌段共聚物所产生的范围。我们报道了一种构象不对称的ABC三嵌段三元共聚物的合成，其中末端嵌段分别是介晶包覆液晶聚合物和聚二甲基硅氧烷，并且其在混合溶剂蒸汽退火下的自组装形成了一系列球形、柱状和穿孔层状核壳形态，以及堆叠的多级结构。通过对小体积分数的含硅核嵌段进行选择性等离子体蚀刻，产生了直径小于7nm的SiO纳米图案，线/间距比约为1:4。此外，这种三元共聚物的构象不对称导致在平坦基底上形成锯齿状圆柱体，并在光刻图案化沟槽内垂直于模板侧壁实现稳定的圆柱体排列。
