期刊
MACROMOLECULES
卷 52, 期 21, 页码 8217-8226出版社
AMER CHEMICAL SOC
DOI: 10.1021/acs.macromol.9b01756
关键词
-
资金
- National Science Foundation [DMR-1709371]
- DOE Office of Science [DE-SC0012704]
- NSF [DMR-0520547]
- EU [654000]
Morphological behavior of PS-PLA bottlebrush copolymers with a compositional gradient along the backbone was investigated by small-angle X-ray scattering (SAXS) analysis and compared to that of their block copolymer analogs. Side chain-symmetric gradient copolymers with varying volume fractions were prepared by one-step ring-opening metathesis polymerization of the corresponding exo- and endo-norbornenefunctionalized macromonomers of similar lengths. The morphological map constructed using the SAXS data revealed a wide cylindrical morphology window, including for symmetric compositions, well-ordered lamella morphologies at very low PS volume fractions, and the formation of a rare bicontinuous gyroid morphology. In addition to the highly asymmetric nature of the morphology diagram, the domain spacings obtained for gradient bottlebrush copolymers were significantly smaller (by 30-40%) than the corresponding bottlebrush block copolymer analogs, which was attributed to a nonperpendicular orientation of the gradient bottlebrush backbone at the domain interface. Side chain-asymmetric gradient bottlebrush copolymers were synthesized from PS and PLA macromonomers of different lengths and were demonstrated to assemble into well-ordered cylindrical and lamella morphologies. The results of these studies demonstrate that the gradient interface plays an important role in determining molecular packing during bottlebrush copolymer self-assembly. A rich morphological behavior of the gradient bottlebrush copolymers combined with their user-friendly onestep synthesis provides a robust and versatile platform for nanostructured material-design and fabrication.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据