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Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
Helix-sense-controlled synthesis of optically active poly(methyl methacrylate) stereocomplexes
Takehiro Kawauchi1, Atsushi Kitaura, Jiro Kumaki
1Yashima Super-structured Helix Project, Exploratory Research for Advanced Technology, Japan Science & Technology Agency, Japan. kawauchi@tutms.tut.ac.jp
Journal of the American Chemical Society
|August 15, 2008
Summary
Optically active poly(methyl methacrylate) stereocomplexes were formed by including isotactic PMMA within a fullerene-encapsulated syndiotactic PMMA helix. This resulted in a triple-stranded helix with preserved macromolecular helicity memory.
Area of Science:
- Polymer Chemistry
- Supramolecular Chemistry
- Chiroptical Spectroscopy
Background:
- Optically active polymers exhibit unique chiroptical properties.
- Macromolecular helicity memory allows polymers to retain specific helical conformations.
- Fullerene encapsulation can template polymer structures.
Purpose of the Study:
- To prepare optically active poly(methyl methacrylate) stereocomplexes.
- To investigate helix-sense-controlled supramolecular inclusion.
- To explore the formation of triple-stranded helical structures.
Main Methods:
- Synthesis of optically active, fullerene-encapsulated syndiotactic PMMA.
- Supramolecular inclusion of isotactic PMMA within the fullerene-PMMA complex.
- Analysis using vibrational circular dichroism (VCD) spectroscopy.
- Computational analysis of VCD spectra.
Main Results:
- Successful preparation of optically active PMMA stereocomplexes.
- Isotactic PMMA replaced encapsulated fullerenes within the syndiotactic PMMA helix.
- Formation of a double-stranded helix by isotactic PMMA with the same handedness as the syndiotactic PMMA single helix.
- Evidence for a topological triple-stranded helix structure.
Conclusions:
- Demonstrated a novel method for creating stereocomplexes with controlled helical structures.
- Established a macromolecular helicity memory effect in triple-stranded PMMA helices.
- Highlighted the role of fullerene templating in directing polymer self-assembly.
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