Manufacturing of cellulose-based nano- and submicronparticles via different precipitation methods

Abstract

Nanoprecipitation is one of the most popular methods for producing polymer nanoparticles. However, the reported results show a large variability. In order to provide a first-hand comparative study, we prepared cellulose-based nanoparticles via different nanoprecipitation methods. Here, the influence of the coagulating solvents acetone, N,N-dimethylacetamide and tetrahydrofuran on the size and shape of the particles via precipitation using dialysis was investigated. The influence of temperature and concentration was determined by dropwise addition of the coagulation medium. Then, via rapid solvent shifting, particles were prepared from cellulose acetates with different molecular masses and the cellulose acetate propionate and cellulose acetate butyrate derivatives in the concentration range of 1–20 mg mL^− 1. Thereby, it was possible to prepare spherical particles in the range from 43 to 158 nm. Furthermore, the impact of the molecular weight of these derivatives on the obtained particle size distributions was determined. It is possible to obtain pure regenerated cellulose particles in the nanometer range by a deacetylation of the derivatives. In addition, the findings were used to directly convert cellulose from a DMAc/LiCl solvent system into regenerated cellulose nanoparticles with a size of 10 ± 3 nm.