Size controlled synthesis of sub-100 nm monodisperse poly(methylmethacrylate) nanoparticles using surfactant-free emulsion polymerization

• Published in: Journal of colloid and interface science 2010-04, Vol.344 (2), p.528-532
• Main Authors: Camli, Sevket Tolga, Buyukserin, Fatih, Balci, Oguz, Budak, Gurer Guven
• Format: Article
• Language: English
• Subjects: Acetone; Atomic force microscopy; Dynamic light scattering; Emulsion polymerization; Emulsions - chemistry; Initiators; Monodisperse; Nanoparticles; Nanoparticles - chemistry; Particle Size; Poly(methylmethacrylate); Polydispersity; Polymethyl Methacrylate - chemical synthesis; Polymethyl Methacrylate - chemistry; Polymethyl methacrylates; Scanning electron microscopy; Surface Properties; Surfactant-free emulsion polymerization
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2010.01.041

We demonstrate a single step synthetic approach that yields poly(methylmethacrylate) (PMMA) nanoparticles with controlled sub-100 nm size and relatively high resultant solid content. Acetone was used as a cosolvent in order to obtain monodisperse sub-100 nm diameter particles. Stable dispersions were obtained for all formulations where the persulfate initiator causes the negative charges on the particle surface. Surfactant-free emulsion polymerization (SFEP) is a well-known technique for the production of polymeric nanoparticles that does not require post-synthetic cleaning steps. Obtaining hydrophobic particles at sub-100 nm scale, however, is quite challenging with this polymerization method. Here, we demonstrate a single step synthetic approach that yields poly(methylmethacrylate) (PMMA) nanoparticles with controlled sub-100 nm size and relatively high resultant solid content. Dynamic light scattering (DLS) was used for the particle characterization. Spherical and uniformly sized nanoparticles were confirmed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). Acetone was used as a cosolvent in order to obtain monodisperse sub-100 nm diameter particles. Stable PMMA nanoparticle dispersions were obtained for all formulations where the persulfate initiator causes the negative charges on the particle surface. The effects of acetone, monomer and initiator concentration were studied to optimize average particle hydrodynamic diameter and polydispersity index of the final particles. Non-crosslinked monodisperse PMMA nanoparticles (polydispersity index less than 0.05) with diameters from 32 nm to 72 nm were synthesized by using this method.