Synthesis of cellulose graft cyclic anhydride and epoxide alternating copolyesters in a DBU/ DMSO/CO2 solvent system

Abstract

A series of cellulose grafted alternating cyclic anhydride (CA) and epoxide (EPO) copolyesters (cell-g-P(CA-alt-EPO)) have been prepared in the novel DBU/DMSO/CO2 cellulose solvent system. The DBU acted both as a reagent for cellulose dissolution and as a catalyst for ring-opening copolymerization (ROCOP) of cellulose with EPO and CA. The structural features and thermal performances of cell-g-P(CA-alt-EPO) were characterized via MALDI-TOF, FT-IR NMR, TGA, DSC and XPS. Perfectly alternating sequence distributions and controlled molecular weights of a series of cell-g-P(CA-alt-EPO) were easily achieved by a variation of the CA or EPO. The cell-g-P(CA-alt-EPO) also had satisfactory UV-absorbing properties and cellulose grafted phthalic anhydride and glycidyltrimethylammonium chloride exhibited outstanding antibacterial behavior. Antibacterial activity against Escherichia coli and Staphylococcus aureus were 96.7% and 99.4% respectively. Thus, cell-g-P(CA-alt-EPO) with good solubility, melt processability, UV absorption and antibacterial properties have potential applications in UV-shielding and antibacterial agent fields.