Recyclable ethyl cellulose film modified by rosin based quaternary ammonium salt for antimicrobial packaging

Antibacterial food packaging can effectively extend the shelf life of food . The bactericidal activity of rosin quaternary ammonium salt has been demonstrated in highly efficient. In this study, a new type of rosin quaternary ammonium salt antibacterial agent was grafted onto ethyl cellulose (EC-B), and the EC/EC-B recyclable composite films (0.5/1/3 wt% EC-B) for packaging material were then prepared by solution casting. These films have high transparency (> 93 % of 400 nm ultraviolet transmittance) and decent tensile strength (∼25 MPa). Because of the grafting of rosin based quaternary ammonium salt, the 1 wt% EC-B/EC film has a satisfactory bactericidal rate (> 97 %) toward both gram-positive and negative bacteria, suggesting its potential broad-spectrum antibacterial effect. In the experiment of food preservation, the apple slices packed with the film doped with 1 wt% EC-B maintained high freshness after three days storage. After two recycling loops, the tensile strength and the bactericidal rate for S. aureus and E. coli of the film were retained at 80 %, 93 %, and 80 % of the initial, respectively. This work explored the feasibility of using recyclable antibacterial cellulose composite in food packaging applications.