SYNTHESIS AND CHARACTERIZATION OF (THIO)CARBAMATES BASED ON CELLULOSE AND CELLULOSE ACETATE: BIODEGRADATION AND SOLUBILITY STUDIES

In this work, a facile method was developed to modify cellulose and cellulose acetate fibers by an approach that consists in converting the hydroxyl groups existing on their surfaces to carbamate, using 1,6-hexamethylene diisocyanate (HDI) as a connecting agent. Firstly, a precursor with a free isocyanate end group was prepared and thereafter it was used for a homogeneous one-pot modification of these raw materials, avoiding toxic solvents and expensive reagents. The obtained derivatives were characterized using FTIR, NMR, TGA/DTG and XRD techniques. The study of their solubility allowed determining the values of the solubility parameters (i), the values of the solventpolymer interaction parameters ( s-p ); therefore, their solvent systems. The biodegradability of cellulose and its derivatives was investigated under aerobic conditions in solid conditions and liquid medium. The results indicated that these raw materials are biodegradable and can substitute currently used industrial non-biodegradable products. They can have some applications in different industrial fields, such as adsorbents, food packaging and antibacterial materials, respecting the protection of the environment. A sustainable development and an increased use of green chemistry principles are among the essential objectives of this work.