Controlling the size and surface morphology of carboxylated polystyrene latex particles by ammonium hydroxide in emulsifier-free polymerization

Hyunbae Dong, Sangyup Lee, Gi Ra Yi

Research output: Contribution to journalArticle

10 Citations (Scopus)


In emulsifier-free, emulsion polymerization with ionizable comonomer, the ionization of the comonomer is critical in determining the size of the final polymeric particles at sub-micrometer scale. In this study, polystyrene latex beads with carboxylates on the surface were synthesized using acrylic acid as a comonomer. Specifically, ammonium hydroxide was added to the emulsifier-free polymerization system to promote the ionization of acrylic acid by increasing pH. Smaller polystyrene latex particles were produced by increasing the ammonium hydroxide concentration in the reaction system, due to the enhanced stability promoted by the ionization of acrylic acid during the nucleation step. In addition, the surface morphology of the polystyrene latex particles was controlled by the concentration of acrylic acid, the dissociation of which was influenced by the ammonium hydroxide concentration.

Original languageEnglish
Pages (from-to)397-402
Number of pages6
JournalMacromolecular Research
Issue number6
Publication statusPublished - 2009 Jan 1


All Science Journal Classification (ASJC) codes

  • Chemical Engineering(all)
  • Organic Chemistry
  • Polymers and Plastics
  • Materials Chemistry

Cite this