Multiresponsive hybrid microgels and hollow capsules with a layered structure

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Stimuli-responsive materials offer dynamic control over particle properties.
• Composite particles and hollow capsules are valuable for various applications.
• Precise control over internal structure is crucial for material performance.

Purpose of the Study:

• To synthesize and characterize stimuli-responsive composite particles and hollow capsules.
• To investigate the influence of synthesis conditions on particle structure and properties.
• To achieve controlled internal structures for pH- and glucose-responsive applications.

Main Methods:

• Synthesis of core-shell particles via polymerization of N-isopropylacrylamide (NIPAM) on silica seeds.
• Characterization using photon correlation spectroscopy, Transmission Electron Microscopy (TEM), and Atomic Force Microscopy (AFM).
• Fabrication of hollow capsules through hydrofluoric acid treatment.

Main Results:

• Uniform core-shell particles achieved by optimizing monomer concentration and silica surface area.
• Shell thickness is dependent on monomer concentration but not silica seed size.
• Tunable volume phase transition temperature by altering N-alkylacrylamide monomers.
• Incorporation of comonomers (AA, PBA) can inhibit core-shell formation but enable functionalization in core-double shell structures.

Conclusions:

• Controlled synthesis of stimuli-responsive composite particles and hollow capsules is feasible.
• Synthesis parameters significantly impact particle morphology and uniformity.
• Method allows for the creation of pH- and glucose-responsive materials with precise internal structural control.