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Controllable porous polymer particles generated by electrospraying

“…Particles with isolated pores were obtained from the chloroform/water-PCL system while the cup-shaped and the golf ball shaped particles were obtained from chloroform and PCL system, which was due to a change in phase separation during the evaporation of solvent. It is speculated that the interaction between PCL and chloroform decreases because of the non-solvent water, and thus facilitates the phase separation of the polymer matrix and solvent [24,26]. When the concentration of PCL and chloroform was increased to 4 w/v% during the electrospraying process, the pores became smaller and more circular but distributed homogeneously in the particles, as shown in Fig.…”

“…It was attributed to the rapid chloroform evaporation at the early state of the ejecting passage from the nozzle to the collector due to the less interaction between the PCL and chloroform. The chloroform molecules were expulsed fast from the electrosprayed droplets, thus PCL polymer chains precipitated and linked in the final stage of the process which resulted in golf ball shaped particles with closed pores on the surface [18,24]. Fig.…”

Preparation of quantum dots encoded microspheres by electrospray for the detection of biomolecules

“…The morphology of electrospray product has shown a great dependence on the concentration of solution and the strength of electric field [50,51]. In this experiment, it is obvious that the jet of polymer solutions from the tip of a capillary begins to break up into droplets at concentration below 13 wt.%.…”

Novel Preparation and Properties of Microspheres involving a Hydrocarbon‐Perfluorocarbon Solvent Extraction Process

“…Particles with a hollow core are formed if the solidification process is too fast, Fig. 1, i.e., the mass transfer of solvent from the droplet into the continuous phase is faster than the diffusion of solvent inside the droplet [12,13].…”

“…The formation of a crust decreases the solvent mass transfer rate. If the solvent diffusion from the droplet through the crust into the continuous phase is not too fast compared to the diffusion of solvent inside the droplet, dense particles are formed [12,13]. Fast diffusion of the solvent from the dispersed phase into the continuous phase creates a high supersaturation of the matrix material at the surface of the solidifying droplets.…”