Use of biodegradable biopolymers and nanocellulose for application in programmable fertilizers release

Abstract

Programmable fertilizer has been intensively studied in the last decades to deliver nutrients in a regular and continuous way to plants. Parallel to these efforts, cellulose-based materials have attracted attention. There is a wide number of recent works involving the development of materials containing cellulose nanoparticles (CNs). CNs have hydroxyl groups on its surface with great potential to interact with ionic compounds, such as the nutrient potassium nitrate. As well, CNs/nutrient can act as a reinforcement for polymeric matrix of programmable fertilizer that will be less aggressive to the environment. As result, it should delay the nutrient releasing and improve the biodegradability properties of the material. In this BEPE, CNs will be functionalized via chemical modification in order to increase the nanocellulose charges negatively and/or positively, and improve the cellulose-fertilizer interaction as well the cellulose-thermoplastic matrix interface. We will focus our efforts in the development of chemical modification processes that can be performed in aqueous or other environmentally friendly solvents. Surface functionalization that uses TEMPO-mediated oxidation, quaternary ammonium salts, anionic surfactants and grafting are considered as potential chemical modification routes. Nanocellulose-based materials will be assessed morphologically, structurally, mechanically and thermally before and after chemical functionalization. (AU)