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Polymer Dispersity Control by Organocatalyzed Living Radical Polymerization
Xu Liu1, Chen-Gang Wang1, Atsushi Goto1
1Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore, Singapore.
Angewandte Chemie (International Ed. in English)
|February 21, 2019
Summary
This study introduces a new method for controlling polymer dispersity (Đ) using temperature-controlled radical generation in polymerization. This technique allows for precise Đ tuning in various polymer architectures without needing external pumps or metals.
Area of Science:
- Polymer Chemistry
- Materials Science
- Organic Synthesis
Background:
- Polymer dispersity (Đ) is crucial for material properties.
- Existing methods for Đ control can be complex or limited.
Purpose of the Study:
- To develop a novel, pump-free method for controlling polymer dispersity (Đ).
- To achieve tunable Đ in diverse polymer architectures and on surfaces.
Main Methods:
- Utilized temperature-selective radical generation in organocatalyzed living radical polymerization.
- Synthesized polymers in a batch system without external pumping.
- Applied the method to create block copolymers, star polymers, brush polymers, and surface-grafted polymer brushes.
Main Results:
- Achieved tunable dispersity (Đ) from 1.11 to 1.50 across various polymer structures.
- Demonstrated successful synthesis of polymers and polymer brushes with controlled Đ.
- Observed unique interactions of polymer brushes with external molecules, dependent on Đ.
Conclusions:
- The novel organocatalyzed polymerization offers a versatile and metal-free approach for precise Đ control.
- This method is applicable to complex polymer architectures and surface modifications.
- Tailored dispersity in polymer brushes influences their interaction with other molecules.
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