High purity nanolatex prepared by ultrasonically irradiated emulsion polymerization

Area of Science:

• Polymer Chemistry
• Materials Science
• Nanotechnology

Background:

• Emulsion copolymerization is a key technique for synthesizing polymer nanoparticles.
• Traditional methods often result in residual surfactants, impacting latex purity and performance.
• Developing efficient, single-step synthesis methods for high-purity nanolatex is crucial.

Purpose of the Study:

• To investigate the ultrasonic-initiated emulsion copolymerization of styrene with a cationic surfmer.
• To prepare high-purity copolymer nanolatex with controlled particle size.
• To demonstrate the multifunctional role of the cationic surfmer in the polymerization process.

Main Methods:

• Ultrasonically initiated emulsion copolymerization of styrene and methacryloxyethyl dodecyldimethyl ammonium bromide (C(12)N(+)).
• Characterization using Fourier-transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance ((1)H NMR).
• Surface tension measurements to assess residual surfactant levels.

Main Results:

• Achieved high styrene conversion (95%) within one hour.
• Produced nanoscale latex particles with an average diameter of 40 nm.
• Confirmed near-complete copolymerization of the surfmer at concentrations above 0.030 g/mL, yielding high-purity nanolatex.

Conclusions:

• Ultrasonic initiation is effective for rapid emulsion copolymerization.
• The cationic surfmer (C(12)N(+)) acts as an efficient emulsifier, initiator, and comonomer.
• This method provides a facile route to high-purity copolymer nanolatex without residual emulsifiers.