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Electronically Stabilized Copoly(Styrene-Acrylic Acid) Submicrocapsules Prepared by Miniemulsion Copolymerization
Minkwan Kim1, Yura Hwang2, Han Do Ghim3
1Department of Textile System Engineering, Kyungpook National University, 80 Daehakro, Bukgu, Daegu 41566, Korea. gundamzxv@naver.com.
Polymers
|April 12, 2019
Summary
This study developed stable poly(styrene-acrylic acid) submicrocapsules using miniemulsion copolymerization. Optimized conditions yielded submicrocapsules with excellent colloidal stability, demonstrating their potential for various applications.
Area of Science:
- Polymer Chemistry
- Materials Science
- Colloid Science
Background:
- Submicrocapsules offer controlled release and enhanced stability for active ingredients.
- Improving the electrostatic stability of submicrocapsules is crucial for preventing aggregation.
Purpose of the Study:
- To prepare and characterize poly(styrene-acrylic acid) (St/AA) submicrocapsules via miniemulsion copolymerization.
- To optimize the miniemulsion copolymerization process for enhanced colloidal stability.
- To evaluate the long-term stability of the synthesized St/AA submicrocapsules.
Main Methods:
- Miniemulsion copolymerization of styrene and acrylic acid using phytoncide oil as a model core.
- Systematic variation of monomer feed ratio, initiator (azobisisobutyronitrile), and surfactant (sodium dodecyl sulfate) concentrations.
- Characterization using dynamic light scattering, microscopic analyses, and Turbiscan Lab for colloidal stability assessment.
Main Results:
- The optimal miniemulsion copolymerization conditions were determined: [AA]/[St] = 0.33, [SDS] = 1.0 × 10⁻³ mol, and [AIBN] = 2.0 × 10⁻³ mol/mol of monomer.
- St/AA submicrocapsules prepared under optimal conditions exhibited a mean particle size of 392.6 nm and a zeta potential of -55.2 mV.
- These optimized submicrocapsules demonstrated excellent long-term colloidal stability with minimal aggregation.
Conclusions:
- Miniemulsion copolymerization is an effective method for producing stable St/AA submicrocapsules.
- Incorporating acrylic acid enhances the zeta potential and electrostatic stability of the submicrocapsules.
- The optimized St/AA submicrocapsules exhibit superior colloidal stability, making them suitable for advanced applications.
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