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Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
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Oxidation promoted self-assembly of π-conjugated polymers
Garion E J Hicks1, Charles N Jarrett-Wilkins1, Jenny R Panchuk1
1Lash Miller Chemical Laboratories, Department of Chemistry, University of Toronto 80 St. George Street Toronto Ontario M5S 3H6 Canada dseferos@chem.utoronto.ca.
Chemical Science
|June 7, 2021
Summary
Researchers developed a new method for self-assembling π-conjugated block copolymers into redox-responsive micelles. This technique utilizes selective oxidative doping, enabling controlled assembly and disassembly for advanced materials.
Area of Science:
- Materials Science
- Polymer Chemistry
- Nanotechnology
Background:
- Self-assembly organizes molecules into ordered structures across multiple length scales.
- Crystallization-Driven Self-Assembly (CDSA) uses block copolymers with distinct solubility blocks to form micelles.
- Current CDSA methods are limited for π-conjugated polymers due to similar block solubilities and lack of reversibility.
Purpose of the Study:
- To develop a method for self-assembly of purely π-conjugated block copolymers.
- To introduce reversible, stimulus-responsive self-assembly for these polymers.
- To overcome limitations of existing CDSA techniques for optoelectronic polymers.
Main Methods:
- Selective oxidative doping of one block in a π-conjugated block copolymer.
- Utilizing heteroatom substitution in polychalcogenophenes to tune oxidation potential.
- Employing chemical reductants to trigger disassembly of assembled structures.
Main Results:
- Spontaneous formation of redox-responsive micelles with a crystalline core and amorphous corona.
- Achieved narrow size distribution of the self-assembled micelles.
- Demonstrated reversible disassembly of micelles upon addition of a chemical reductant.
Conclusions:
- Selective oxidative doping is a viable strategy for π-conjugated block copolymer self-assembly.
- This method enables the creation of stimuli-responsive nanomaterials from optoelectronic polymers.
- Expands the range of polymers amenable to controlled self-assembly and introduces redox-responsiveness.
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