Computational fluid dynamic study of polycaprolactone nanoparticles precipitation in a co‐flow capillary micro‐tube

Abstract

Polycaprolactone nanoparticles (NPs) were produced in the co‐flow glass capillary device with 250μm tip dimension. NPs size was 990 nm for continuous phase velocity, and uc=0.05m/s and 426 nm for uc=0.2m/s. The droplet formation process in the co‐flow microchannel was also simulated using computational fluid dynamic (CFD). Employing a digital image analysis technique, a cut‐off value of 0.81 for the dispersed phase volume fraction was proposed for the determination of droplet size. A scenario was expressed for NP formation from micro‐droplets. Moreover, after conducting 27 CFD simulations, a dimensionless exponential form correlation was proposed for droplet size estimation. In this generalized map, there were three distinct regions based on the relative capillary numbers of continuous to dispersed phases. It was revealed that at a constant dispersed phase velocity, by increasing the continuous phase velocity, more small NPs are formed. The results show that the ratio of micro‐droplets to NPs size was between 735 and 755.

Effects of the microchannel shape upon droplet formations during synthesis of nanoparticles

“…Setting relative velocity, continuous phase viscosity, surface tension, and type and concentration of surfactants allows for creation of Janus droplets with various morphologies. Saeed et al [23].…”