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Abstract Intimately connected to the rule of life, chirality remains a long-time fascination in biology, chemistry, physics and materials science. Chiral structures, e.g., nucleic acid and cholesteric phase developed from chiral molecules are common in nature and synthetic soft materials. While it was recently discovered that achiral but bent-core mesogens can also form chiral helices, the assembly of chiral microstructures from achiral polymers has rarely been explored. Here, we reveal chiral emergence from achiral conjugated polymers, in which hierarchical helical structures are developed through a multistep assembly pathway. Upon increasing concentration beyond a threshold volume fraction, dispersed polymer nanofibers form lyotropic liquid crystalline (LC) mesophases with complex, chiral morphologies. Combining imaging, X-ray and spectroscopy techniques with molecular simulations, we demonstrate that this structural evolution arises from torsional polymer molecules which induce multiscale helical assembly, progressing from nano- to micron scale helical structures as the solution concentration increases. This study unveils a previously unknown complex state of matter for conjugated polymers that can pave way to a field of chiral (opto)electronics. We anticipate that hierarchical chiral helical structures can profoundly impact how conjugated polymers interact with light, transport charges, and transduce signals from biomolecular interactions and even give rise to properties unimagined before.
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Herman F. Mark: Pioneer in structural chemistry, molecular biology, and polymer science
Herman Francis Mark produced brilliant contributions to the fields of organic chemistry, structural chemistry, molecular biology, and polymer science in academia and in industry in four different countries from two continents. This Legacy article outlines the author’s view on how Mark, who was universally known as the father of polymer science, also pioneered the science, education, publishing, and lecturing styles for the fields of structural chemistry and molecular biology with his disciplined and elegant leadership.
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- Award ID(s):
- 2104554
- PAR ID:
- 10523920
- Publisher / Repository:
- Cell Press
- Date Published:
- Journal Name:
- Chem
- Volume:
- 9
- Issue:
- 12
- ISSN:
- 2451-9294
- Page Range / eLocation ID:
- 3386 to 3393
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.chempr.2023.10.021
