Investigation of High Penetration and Dispersion of Functional Nanoparticles in Leather

The use of nanoparticle-based functional leather products has stimulated sustainable growth of the conventional leather industry. However, functional nanoparticles (FNPs) face challenges to be well penetrated and dispersed in leather because of their aggregation and mismatch charges with leather. In this study, the acrylic resin (AR) retanning agent, which was originally utilized in leather processing, was applied for the modification of FNPs. It has been demonstrated that AR can improve the electrostatic and steric repulsion among nanoparticles, inhibiting their aggregation and ensuring their penetration and dispersion in leather. Because of the limitation of leather porosity, the maximum loading amount for FNPs was about 40wt% (based on leather weight). The leather got higher results in fullness, thickening ratio, and tensile strength when the loading amount of FNPs was 11.25%. Moreover, the proposed approach in this study can be used well for other types of FNPs loaded in leather, suggesting its broad applicability.