Effect of coated and encapsulated polyacrylate/nano-SiO2 composite emulsions on the finishing performances of leather via miniemulsion polymerization

Abstract

In this study, the polyacrylate/nano-SiO2 (PA/SiO2) composite emulsion with ideal encapsulated and coated morphologies were prepared by miniemulsion polymerization. They, respectively, are encapsulated PA/SiO2-S composite emulsion, coated PA/SiO2-Q and PA/SiO2-W composite emulsion. The morphology of the composite emulsions were characterized by transmission electron microscope, and the results showed that the nano-SiO2 were encapsulated inside or coated around the latex particles. We investigated microstructure and properties of the composite emulsions after film formation which effect by nano-SiO2 existence forms by scanning electron microscope, thermogravimetric analysis, tensile strength, elongation at break and water absorption test. The PA/SiO2-W composite film had the best tensile strength of 6.3 MPa and a maximum thermal decomposition temperature of 415.2 °C. Furthermore, the PA/SiO2 composite emulsions were applied to leather finishing. The results demonstrated that the PA/SiO2-W composite emulsion increased the breathability and water vapor permeability of leather simple to 210.8% and 69.8%, respectively, which shows the emulsion has excellent comprehensive performance and potential application as the leather finishing agent.