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Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers
Published on: June 20, 2019
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In situ generation and evolution of polymer toroids by liquid crystallization-assisted seeded dispersion
Mingxin Zheng1, Qiquan Ye1, Xi Chen2
1Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China. yuanjy@mail.tsinghua.edu.cn.
Chemical Communications (Cambridge, England)
|May 31, 2022
Summary
Researchers developed a novel method using liquid crystallization-assisted seeded dispersion polymerization to create azobenzene triblock copolymer toroids. These structures transform morphologically under UV light, offering potential for advanced functional nanomaterials.
Area of Science:
- Polymer Chemistry
- Materials Science
- Nanotechnology
Background:
- Polymer self-assembly is crucial for creating functional nanomaterials.
- Controlling polymer morphology is key to tailoring material properties.
- Azobenzene-containing polymers offer photo-responsive capabilities.
Purpose of the Study:
- To develop a method for preparing high solid content azobenzene-containing triblock copolymer toroidal assemblies.
- To investigate the formation and transformation of these toroidal structures.
- To explore their potential as functional nanomaterials.
Main Methods:
- Utilized liquid crystallization-assisted seeded dispersion polymerization.
- Employed polymerization-induced self-assembly (PISA) to form vesicles as seeds.
- Introduced smectic liquid crystalline (LC) ordering into the core-forming block.
- Investigated morphological changes under ultraviolet (UV) irradiation.
Main Results:
- Successfully prepared high solid content azobenzene-containing triblock copolymer toroidal assemblies.
- Achieved in situ formation of toroids by incorporating LC ordering.
- Observed a morphological transformation from toroids to barrels upon UV irradiation due to azobenzene photo-isomerization.
Conclusions:
- The developed seeded dispersion polymerization strategy effectively produces tunable anisotropic morphologies.
- Azobenzene-containing LC copolymers can be transformed morphologically using light stimuli.
- This approach expands the possibilities for creating advanced functional nanomaterials.
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