Abstract
This work reports the preparation and characterization of poly(styrene-acrylic acid) (St/AA) submicrocapsules by using the miniemulsion copolymerization method. AA was introduced to miniemulsion polymerization of St to increase the zeta potential and the resulting electrostatic stability of St/AA submicrocapsules. Phytoncide oil was adopted as the core model material. Miniemulsion copolymerization of St and AA was conducted at a fixed monomer concentration (0.172 mol) with a varying monomer feed ratio [AA]/[St] (0.2, 0.25, 0.33, 0.5, and 1.0). Concentrations of initiator (azobisisobutyronitrile; 1.0 × 10−3, 2.0 × 10−3, 3.0 × 10−3, and 4.0 × 10−3 mol/mol of monomer) and surfactant (sodium dodecyl sulfate; 0.6 × 10−3, 1.0 × 10−3, and 1.4 × 10−3 mol) were also controlled to optimize the miniemulsion copolymerization of St and AA. Dynamic light scattering and microscopic analyses confirmed the optimum condition of miniemulsion copolymerization of St and AA. Long-term colloidal stability of aqueous St/AA submicrocapsule suspension was evaluated by using TurbiscanTM Lab. In this work, the optimum condition for miniemulsion copolymerization of St and AA was determined ([AA]/[St] = 0.33; [SDS] = 1.0 × 10−3 mol; [AIBN] = 2.0 × 10−3 mol/mol of monomer). St/AA submicrocapsules prepared at the optimum condition (392.6 nm and −55.2 mV of mean particle size and zeta potential, respectively) showed almost no variations in backscattering intensity (stable colloids without aggregation).
Highlights
Deliveries of functional hydrophobic materials using polymeric nanoparticles have been of great interest in biomedical sciences [1,2,3,4,5,6]
The salient feature of our current study is that miniemulsion copolymerization of St with acrylic acid (AA)
The particle size of the St/AA submicroparticle presents a minimum value of 392.6 nm at 0.33 of the monomer feed ratio (Figure 1a)
Summary
Deliveries of functional hydrophobic materials using polymeric nanoparticles have been of great interest in biomedical sciences [1,2,3,4,5,6]. There are many methodologies for preparing nanoparticles including miniemulsion polymerization [10,11,12,13], interfacial polymerization, solvent evaporation, solvent deposition, nanoprecipitation, desolvation of natural polymers [14], and emulsification–diffusion [15,16,17]. Among these methods, miniemulsion polymerization is conducted by adopting cosurfactants such as hexadecane, cetyl alcohol, and so on. Resulting nanoparticles and submicroparticles show insufficient dispersibility because of particle coagulation due to a lack of surface charge
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
