Synthesis, characterization and antibacterial properties of novel cellulose acetate sorbate

[Display omitted] •CASA was synthesized via esterification of CA and SA.•The raw materials were environmental-friendly and low-cost.•All CASA showed excellent antibacterial activity for E. coli and S. aureus.•The antibacterial groups can be linked to CA more firmly by chemical bonds. In this paper, cellulose acetate (CA) with different degree of substitution (DS) of 2.17∼1.75 were obtained through hydrolysis of cellulose diacetate (CDA). Furthermore, novel cellulose acetate sorbate (CASA) were synthesized by esterification of CA and sorbic acid (SA). The DS of sorbyl groups varied within 0.12–1.20 by adjusting composition ratio, reaction time and temperature. Fourier transform infrared spectroscopy (FTIR), Nuclear magnetic resonance spectroscopy (NMR) and elemental analysis were used to determine the chemical structure. Scanning electron microscopy (SEM) indicated CASA showed denser surface morphology than CA. Thermal properties and crystallization of CASA were slightly decrease but did not affect their service performance. Specifically, all CASA showed excellent antibacterial ability, the maximum relative bactericidal rate reached 81.5 % for Escherichia coli (E. coli) and 95.4 % for Staphylococcus aureus (S. aureus), respectively. Moreover, the obtained CASA films using casting technique possessed good mechanical properties. These antibacterial CASA exhibited potential application in healthcare fields.