In Situ Synthesis of Plasticized Bacterial Cellulose Films for Daily Packaging Using Biobased Plasticizers

Bacterial cellulose (BC) naturally decomposes in the environment without releasing toxins or microplastics, making it a promising alternative to conventional plastics. However, its inherent brittleness after drying limits its broader application. This study investigates four biobased plasticizers─epoxy soybean oil, castor oil, tributyl citrate (TBC), and tributyl trans-aconitate (TBA)─to enhance the flexibility of BC through in situ modification. By combining a gel-assisted biosynthesis with an in situ spray plasticization method, biobased plasticizers are uniformly incorporated into the nanofiber network of BC, resulting in films with significantly improved flexibility and transparency. Among the biobased plasticizers, TBC and TBA showed the most effective plasticization, increasing the E% to 9.63 and 11.90%, respectively, corresponding to 6.3-fold and 7.5-fold enhancements compared to the control. This approach not only improves the mechanical properties of BC but also streamlines production by enabling a simplified processing method. The findings underscore the potential of plasticized BC biomaterials in replacing fossil-based plastics and advancing the development of sustainable materials.