Thermoreversible Polymer Gels in DMF Formed from Charge- and Crystallization-Induced Assembly

Area of Science:

• Materials Science
• Polymer Chemistry
• Supramolecular Chemistry

Background:

• Polymer organogels are typically formed in non-polar solvents.
• Fabrication of polymer organogels in polar solvents via ionic interactions is less common.
• Understanding microphase separation and properties is crucial for applications.

Purpose of the Study:

• To fabricate polymer organogels in a polar solvent (DMF) using a specific triblock copolymer and a fluorinated surfactant.
• To investigate the microphase separation and structural properties of these novel organogels.
• To explore the responsiveness of the organogels to external stimuli.

Main Methods:

• Fabrication of polymer organogels using poly(4-vinyl pyridine)-block-poly(ethylene glycol)-block-poly(4-vinyl pyridine) (4VPm-EGn-4VPm) and perfluorooctanoic acid (PFOA).
• Characterization using small-angle X-ray scattering (SAXS) for microphase separation.
• Characterization using wide-angle X-ray scattering (WAXS) for crystalline structures.

Main Results:

• Ordered microphase separation and crystalline structures were observed in the 4VPm-EGn-4VPm/PFOA organogels.
• The organogels demonstrated sensitivity to temperature.
• Reversible changes were observed in the ratio of PFOA to pyridine groups.
• The polymer organogels responded to the addition of triethylamine and triethylammonium acetate.

Conclusions:

• Novel polymer organogels were successfully fabricated in a polar solvent (DMF).
• The organogels exhibit ordered structures and responsiveness to temperature and chemical stimuli.
• These findings suggest potential applications for these dynamic polymer organogels.