• Journal of Adhesion and Interface
• /
• v.4 no.1
• /
• pp.35-42
• /
• 2003

Polystyrene nanocapsules containing octadecane as a core material were prepared by miniemulsion polymerization. The morphology and size of the nanocapsules were measured with varying the surfactant concentration, content of initiator, core/shell ratio and content of comonomer. The morphologies of the prepared nanoparticles were examined by a scanning electron microscope, a transmission electron microscope and the core material was confirmed by a differential scanning calorimeter. The particles below 70 nm in diameter were formed at a high surfactant concentration. The size of the nanoparticles was not significantly affected by the initiator content. With increasing the core/shell ratio and polar comonomer content, the particle size and its distribution were increased.

• Polymer(Korea)
• /
• v.28 no.1
• /
• pp.10-17
• /
• 2004

Poly(vinyl acetate) (PVAc) nanoparticles were synthesized in oil/water miniemulsion polymerization in the presence of low amount of hexadecane as a cosurfactant. The nanoparticles were tested to apply as a drug carrier. The shape of nanoparticles was observed by scanning electron microscopy, and the average particle size and size distribution were examined by particle size analyzer. Inclusion of antibiotic drugs into the nanoparticles was confirmed by CHO, C=O, and OH peak of FT-IR. Size of the nanoparticles were adjusted between 80∼300 nm by changing the homogenization rate and amount of cosurfactant and surfactant. The monomer droplets prepared by miniemulsion method using a cosurfactant were homogeneous and stable compared with those prepared by conventional emulsion polymerization. This might be occurred due to the prevention of Ostwald ripening and coalescence between droplets by using hexadecane as a cosurfactant.

• Journal of Pharmaceutical Investigation
• /
• v.40 no.2
• /
• pp.73-78
• /
• 2010

Hydrogels are thought to be a promising delivery carrier for protein drugs because of their favorable aqueous environment compared with nano/micro-particles of hydrophobic polymer such as PLGA. In this study, nano-sized hydrogels (nanogels) were fabricated using inverse-miniemulsion polymerization method. The mean size of nanogels in range of 90-160nm and affected by the preparation parameters such as sonication time and concentration of monomer. While longer sonication time and lower concentration of acrylamide monomer showed a tendency to produce smaller nanogels and to have lower lysozyme activity, variation of bis-methylene acrylamide concentration made no difference. Although both longer soncaton time and lower acrylamide concentration increased in vitro release rate, acrylamide concentration was more effectively affected to the control of protein release rate, which indicated that the release rate of protein from nanogels affected by not only their size but also internal structure. In conclusion, nanogels prepared by inverse-miniemulsion can be a useful carrier for application of protein drug, because of simple process, minimum contact of organic solvent and high protein activity.

• Rubber Technology
• /
• v.6 no.1
• /
• pp.10-25
• /
• 2005

• Proceedings of the Polymer Society of Korea Conference
• /
• 2006.10a
• /
• pp.330-330
• /
• 2006

The elaboration of fluorescent submicronic polymer particles exhibiting narrow particle size distribution as well as good photostability is of particular interest in various biomedical applications. In the frame of this work, labeled polystyrene latexes have been synthesized by miniemulsion polymerization using luminescent semiconductor nanoparticles (quantum dots, QD). The influence of incorporation of QDs on the polymerization kinetics as well as on the optical properties of the obtained latexes will be discussed.

• Textile Coloration and Finishing
• /
• v.32 no.4
• /
• pp.226-231
• /
• 2020

This study investigated effect of particle sizes of polymer binders for digital textile printing(DTP) pigment inks on touch of fabrics. The polymer binders were synthesized via miniemulsion polymerization of methyl methacrylate(MMA), butyl acrylate(BA), N-ethylolacrylamide(NEA) and methacrylic acid(MAA). The prepared binders were applied to black pigment inks and those black pigment inks were used to dye cotton fabrics. Then, color strength, rubbing fastness, stiffness, surface and bending properties of the dyed fabrics were investigated. Depending on the particle size of the polymer binder used, color strength, friction fastness, stiffness, surface and bending properties change. Generally, the larger the particle size of the polymer binder, the softer properties.

• Macromolecular Research
• /
• v.17 no.11
• /
• pp.931-933
• /
• 2009

• Korean Chemical Engineering Research
• /
• v.46 no.4
• /
• pp.669-675
• /
• 2008

Carbon black has been widely used in composites, tonor resin, and ink materials. Since carbon black readily agglomerates, it is important to disperse carbon black in real applications. Aiming to improve dispersion stability, carbon black was chemically oxidized to possess hydroxyl groups using a phase transfer catalyst at room temperature. The modified carbon black (CB-OH) was grafted by a silane coupling agent, p-methylacryloxypropyltrimethoxysilane, to carry teminal vinyl groups. The modified carbon black was subsequently used in miniemulsion polymerization to achieve encapsulted core-shell structure. Finally, well-encapsulated carbon black by polymer was obtained in the size range of 100-500 nm. Throughout the polymerization, the effects of surface modification, types of monomers, initiators, and emulsifiers were investigated.

• Elastomers and Composites
• /
• v.44 no.1
• /
• pp.34-40
• /
• 2009

New coupling agent or surface modified agent (9-decenoic acid) was used to enhance the compatibility between silica and polystyrene in silica/polystyrene hybrid nanocomposite, synthesized by in situ miniemulsion polymerization. Composites contain well dispersed nanosize silica particles. Related tests and analyses confirmed the success of synthesis. Functionalization of silica by 9-decenoic acid and silica on the polystyrene was confirmed by FTIR. TGA showed presence and amount of silica in final latex. The glass transition temperature of the hybrid nanocomposite was increased with the silica amount. SEM and TEM analysis showed the spherical morphology of PS and composite with an average diameter of 55 nm. The presence of silica within composite was confirmed by EDS attached to the existing TEM.

• Polymer(Korea)
• /
• v.29 no.1
• /
• pp.8-13
• /
• 2005

Polystyrene (PS) particles containing the phase change material (PCM) were synthesized by miniemulsion polymerization. The polymer particles prepared with different parameters were investigated in terms of average particle size, particle distribution, and latent heat storage of encapsulated paraffin wax (PW) as PCM. The morphology and particle features of PS particles were analyzed by scanning electron microscope and particle size analyzer, respectively. As a result, the diameters of PS particles were adjusted with manufacturing conditions. The stable and spherical PS particles of nanosize were obtained by miniemulsion polymerization, which could be attributed to the prevention of Ostwald ripening by cosurfactant. Thermal properties of PS particle containing PCM were studied by differential scanning calorimetry. From DSC freeze-thaw cycle, PCM coated with PS exhibited the thermal energy storage and release behaviors, and the latent heat was found to be a maximum 145 J/g. It was noted that PS particles containing PCM showed a good potential as a thermal energy storage medium.