BIODEGRADABLE PLA COATINGS WITH IMPROVED PROPERTIES USING SCALABLE TiO2/SiO2 CORE-SHELL PIGMENTS FOR SUGARCANE BAGASSE PACKAGING PAPER

This study focuses on the development of coating films composed of biodegradable polylactic acid combined with the new TiO2/SiO2 core-shell pigment for enhancing the properties of paper sheets used in packaging, besides overcoming the limitations of its individual components. The study proceeded through investigating the impact of the different pigment concentrations on the structural, mechanical and barrier properties of the coated paper. Coated papers with biodegradable materials are essential for improving their different properties, such as density, surface gloss, smoothness, and moisture resistance. The core-shell pigment that was prepared in this study using a very simple chemical technique based on the co-precipitation of the TiO2/SiO2 components at specific temperature and pH can offer advanced properties by overcoming the deficiencies of both titanium and silicon dioxides individually through their combination in a new compound with improved properties, which can provide advanced packaging papers of low cost. Different concentrations (0.25%, 0.5%, 1%, and 2%) of core-shell TiO₂/SiO₂ were mixed with PLA, and the resulting formulations were used to coat the paper sheets. The corresponding physical and chemical properties were assessed using FTIR, TGA, TEM, SEM, and EDX. Furthermore, the mechanical strength and water vapor characteristics of the paper sheets treated with PLA-TiO2/SiO2 were assessed. The findings were satisfying, which can contribute to the progress of sustainable and functional packaging materials, as well as emphasizing the importance of core-shell pigments in improving the performance of such materials.