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Updated: Jan 30, 2026
11:34
Controlled Synthesis and Fluorescence Tracking of Highly Uniform PolyN-isopropylacrylamide Microgels
Published on: September 8, 2016
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PEGylated NiPAM microgels: synthesis, characterization and colloidal stability.
Julien Es Sayed1, Cédric Lorthioir, Patrick Perrin
1Soft Matter Sciences and Engineering, ESPCI Paris, PSL University, Sorbonne Université, CNRS, F-75005 Paris, France. nicolas.sanson@espci.fr.
Soft Matter
|January 18, 2019
Summary
This study synthesized N-isopropylacrylamide (NiPAM) microgels with poly(ethylene glycol)methacrylate (PEG) for enhanced stability. The PEG incorporation improved colloidal stability in electrolytes at high temperatures.
Area of Science:
- Polymer Chemistry
- Materials Science
- Nanotechnology
Background:
- Thermoresponsive microgels are valuable for various applications.
- Controlling microgel properties like size and stability is crucial for performance.
- N-isopropylacrylamide (NiPAM) microgels exhibit temperature-dependent swelling and deswelling.
Purpose of the Study:
- To synthesize highly stable thermoresponsive microgels.
- To investigate the effect of poly(ethylene glycol)methacrylate (PEG) incorporation on NiPAM microgel properties.
- To enhance the colloidal stability of microgels in electrolyte solutions.
Main Methods:
- Surfactant-free precipitation polymerization of NiPAM with PEG macro-comonomer and MBA crosslinker.
- Characterization using dynamic light scattering (DLS), scanning electron microscopy (SEM), zetametry, 1H NMR, and micro-differential scanning calorimetry (μDSC).
Main Results:
- PEG incorporation controlled microgel size and polydispersity.
- PEG chains were primarily located on the microgel periphery.
- PEG presence significantly enhanced colloidal stability in electrolyte solutions at elevated temperatures.
- Thermal behavior (enthalpy, VPTT) remained similar to pure NiPAM microgels.
Conclusions:
- PEGylated NiPAM microgels offer tunable size and enhanced colloidal stability.
- The peripheral location of PEG chains is key to improved stability.
- These microgels show promise for applications requiring stability in challenging environments.
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