pH-Tunable Thermoresponsive PEO-Based Functional Polymers with Pendant Amine Groups.
Joonhee Lee1, Alaina J McGrath2, Craig J Hawker2
1Department of Chemistry, School of Natural Science, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Korea.
ACS Macro Letters
|June 2, 2022
Summary
Researchers developed pH-tunable thermoresponsive polymers using poly(ethylene oxide) (PEO) with amine side chains. These smart materials exhibit adjustable cloud points, offering new possibilities for advanced applications.
Area of Science:
- Polymer Chemistry
- Materials Science
Background:
- Thermoresponsive polymers with lower critical solution temperatures (LCSTs) are crucial for smart materials.
- Poly(ethylene oxide) (PEO) based polymers are widely explored for their unique properties.
Purpose of the Study:
- To synthesize and characterize pH-tunable thermoresponsive PEO-based polymers.
- To investigate the impact of pendant amine groups and side chain hydrophobicity on polymer cloud points.
Main Methods:
- Controlled anionic ring-opening copolymerization of ethylene oxide (EO) and allyl glycidyl ether (AGE).
- Introduction of aminothiol side chains via thiol-ene click chemistry.
- Tuning of cloud points by varying pendant amine groups and side chain hydrophobicity under different pH conditions.
Main Results:
- Successfully synthesized well-defined PEO-co-AGE copolymers.
- Demonstrated tunable cloud points ranging from 44-100 °C by modifying pendant amine groups (primary, dimethylamine, diethylamine) and side chain hydrophobicity (ethyl, propyl, hexyl).
- Established a systematic relationship between PEO copolymer side chains and cloud point behavior.
Conclusions:
- This study presents the first systematic investigation into the effect of PEO copolymer side chains on cloud point.
- The developed functional polymers offer tunable thermoresponsive behavior, enabling new smart material applications.
- The pH-tunable nature of these polymers expands their potential use in various advanced technologies.
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