1 research outputs found
Size-Controlled Preparation of Polyethylene Nanoplastic Particles by Nanoprecipitation and Insights into the Underlying Mechanisms
Plastic pollution is ubiquitous in the environment, and
nanoplastics
(<1 μm) are of growing concern as they pose more health risks
than larger particles. However, because of a lack of appropriate model
particles, studies examining the risks of polyolefin nanoplastics
are very limited, despite the prevalence of these plastics in the
environment. Although nanoprecipitation using organic solvents is
a promising method for preparing model nanoplastic particles of polyolefins,
there are currently no methods for controlling the particle size.
Here, we examined how the concentration and volume of the feedstock
polymer solution affect the size of polyethylene particles produced
by nanoprecipitation. The mechanisms underlying the particle formation
were investigated by using a simple population balance model. Increasing
the concentration of the feedstock solution increased the growth rate
and decreased the nucleation rate, and increasing the volume of the
feedstock solution increased the growth rate, resulting in an increase
in the mean particle diameter in both cases. These changes in particle
diameter were linearly correlated with the suspension density of the
dispersion up to a suspension density of 0.4 mg·mL–1. In addition, at these suspension densities, spherical particles
were prepared without generating aggregates. Together, these results
show that the diameter of polyethylene particles prepared by nanoprecipitation
could be controlled according to the suspension density up to a suspension
density of 0.4 mg·mL–1. This study provides
a basis for the development of nanoprecipitation-based techniques
for the precise, scale-independent production of model nanoplastic
particles, which we hope will accelerate the risk assessment of nanoplastics