Synthesis of Cationic Nanogels Through Microemulsion Polymerization

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Synthesis of Cationic Nanogels Through
Microemulsion Polymerization

• Tamona Williams
• SPGRE 2001 Research
• University of North Carolina
• Department of Chemistry

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Microemulsion
A water-in-oil microemulsion is an optically
transparent mixture oil, water,and surfactant.
Water droplets are in a continuous oil phase
stabilized by surfactant.
Continuous Oil Phase
Surfactant Molecules
Water Droplets
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Microscopic Appearance Microemulsion
Polymerization
Surfactant and oil phase removed
Initiator added in oil phase
Isolation of Particles in H2O
Microemulsion
Polymerization
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Structure of Monomers Used in Microemulsion
Polymerization
PEGdiacrylate
2-Hydroxylethylacrylate
2-Acryloxyethyltrimethylammonium chloride
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Characterization of Nanogels
Proton NMR
Transmission Electron Microscopy
Dynamic Light Scattering
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TEM Images of Cationic Nanogels
0 Charged Monomer
12 Charged Monomer
6 Charged Monomer
66K Magnification on Copper-Formvar Grid and
Stained with PTA
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Dynamic Light Scattering Data
Diameter of Nanogels by Dynamic Light Scattering
of Charged Monomer in sample Avg. Diameter of nanogels (nm)
0 38 2
6 35 2
12 32 2

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Formulation of Microemulsions with Charged Monomer
Objective To form microemulsion with increased
amount of 2-acryloxyethyltrimethylammonium
chloride
Increasing Monomer Concentration
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Phase Diagram for Laureth-3
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Conclusions

• Cationic nanogels were formed with a maximum of
  12 charged monomer.
• Decreasing the amount of surfactant allows the
  formulation of microemulsions at high percentages
  of charged monomer.
• Further analysis of how surfactant controls the
  amount of charged monomer that will formulate a
  microemulsion, may aid in developing nanogels
  with more charge.

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Acknowledgements

• SPGRE National Science Foundation
• Dr. Joeseph DeSimone
• Dr. Michael Rubenstein
• Karen Erford