The membrane emulsification method was adopted to prepare monodisperse polystyrene(PS) microspheres. Stable uniform-sized emulsion droplets were successfully obtained by pressing PS solution through the Shirasu Porous...The membrane emulsification method was adopted to prepare monodisperse polystyrene(PS) microspheres. Stable uniform-sized emulsion droplets were successfully obtained by pressing PS solution through the Shirasu Porous Glass(SPG) membrane into water solution containing emulsifiers at appropriate applied pressures. Monodisperse PS microspheres with size in the range of 2-20 μm were prepared by drying in liquid. The size of PS microspheres was strongly dependent on the pore size of SPG membrane and the concentration of PS solution. The size of the PS microspheres increased with the increase in the pore size of SPG membrane and the concentration of PS.展开更多
Magnetic polymer particles have found applications in diverse areas such as biomedical treatments, diagnosis and separation technology. These applications require the particles to have controlled sizes and narrow size...Magnetic polymer particles have found applications in diverse areas such as biomedical treatments, diagnosis and separation technology. These applications require the particles to have controlled sizes and narrow size distributions to gain better control and reproducibility in use. This paper reviews recent developments in the preparation of magnetic polymer particles at nano- and micro-scales by encapsulating magnetic components with dissolved or in situ formed polymers. Particle manufacture using emulsification and embedment methods produces magnetic polymer particles at micro-scale dimensions. However, the production of particles in this range using conventional emulsification methods affords very limited control over particle sizes and polydispersity. We report on alternative routes using membrane and microfluidics emulsification techniques, which have a capability to produce monodisperse emulsions and polymer microspheres (with coefficients of variation of less than 10%) in the range from submicrometer to a few 100 μm. The performance of these manufacturing methods is assessed with a view to future applications.展开更多
A new reactor with integrated conventional slurry stirred reactor and ceramic external membrane emulsification system, was introduced in this paper. Toluene and toluene containing surfactant was separately used as dis...A new reactor with integrated conventional slurry stirred reactor and ceramic external membrane emulsification system, was introduced in this paper. Toluene and toluene containing surfactant was separately used as dispersed phase for preparation of emulsions. Two kinds of emulsions were prepared and compared. The volume average sizes of prepared emulsions were 3.53μm and 3.6μm respectively. The results showed that the droplet sizes of two kinds of emulsions were similar, but the monodispersed emulsion was only obtained with addition of surfactant into the dispersed phase.展开更多
Much attention has in recent years been paid to fine applications of polymer particles, e.g., carrier for enzyme, separation media for protein, DNA and cell, and carrier for drug in Drug Delivery System (DDS). Control...Much attention has in recent years been paid to fine applications of polymer particles, e.g., carrier for enzyme, separation media for protein, DNA and cell, and carrier for drug in Drug Delivery System (DDS). Control of polymer particle size is especially important in such fine applications. For instance, when the particles are used as a carrier of anti-cancer agents, the locations of particles containing anti-cancer agents also depend on the size of the particles. In this paper, various techniques of controlling polymer particle size are described, with emphasis on Shirasu Porous Glass (SPG) membrane emulsification, as carried out in our research group.展开更多
文摘The membrane emulsification method was adopted to prepare monodisperse polystyrene(PS) microspheres. Stable uniform-sized emulsion droplets were successfully obtained by pressing PS solution through the Shirasu Porous Glass(SPG) membrane into water solution containing emulsifiers at appropriate applied pressures. Monodisperse PS microspheres with size in the range of 2-20 μm were prepared by drying in liquid. The size of PS microspheres was strongly dependent on the pore size of SPG membrane and the concentration of PS solution. The size of the PS microspheres increased with the increase in the pore size of SPG membrane and the concentration of PS.
文摘Magnetic polymer particles have found applications in diverse areas such as biomedical treatments, diagnosis and separation technology. These applications require the particles to have controlled sizes and narrow size distributions to gain better control and reproducibility in use. This paper reviews recent developments in the preparation of magnetic polymer particles at nano- and micro-scales by encapsulating magnetic components with dissolved or in situ formed polymers. Particle manufacture using emulsification and embedment methods produces magnetic polymer particles at micro-scale dimensions. However, the production of particles in this range using conventional emulsification methods affords very limited control over particle sizes and polydispersity. We report on alternative routes using membrane and microfluidics emulsification techniques, which have a capability to produce monodisperse emulsions and polymer microspheres (with coefficients of variation of less than 10%) in the range from submicrometer to a few 100 μm. The performance of these manufacturing methods is assessed with a view to future applications.
基金the National Basic Research Program of China (No. 2003CB615700) the National Natural Science Foundation of China (No. 20125618).
文摘A new reactor with integrated conventional slurry stirred reactor and ceramic external membrane emulsification system, was introduced in this paper. Toluene and toluene containing surfactant was separately used as dispersed phase for preparation of emulsions. Two kinds of emulsions were prepared and compared. The volume average sizes of prepared emulsions were 3.53μm and 3.6μm respectively. The results showed that the droplet sizes of two kinds of emulsions were similar, but the monodispersed emulsion was only obtained with addition of surfactant into the dispersed phase.
文摘Much attention has in recent years been paid to fine applications of polymer particles, e.g., carrier for enzyme, separation media for protein, DNA and cell, and carrier for drug in Drug Delivery System (DDS). Control of polymer particle size is especially important in such fine applications. For instance, when the particles are used as a carrier of anti-cancer agents, the locations of particles containing anti-cancer agents also depend on the size of the particles. In this paper, various techniques of controlling polymer particle size are described, with emphasis on Shirasu Porous Glass (SPG) membrane emulsification, as carried out in our research group.