An innovative approach to develop plant‑derived and CO2‑based active biocomposite films towards antioxidant activity

In this study, novel biocomposites composed of CO2-derived poly(propylene) carbonate and plant-based cellulose were developed employing solvent casting technique. An innovative and rapid strategy was employed, whereby pre-dissolving cellulose improves dramatically the compatibility of poly(propylene) carbonate with cellulose whilst pristine cellulose powder displays inhomogeneous distributions of cellulose within the biocomposite. Resulting biocomposites produce fat homogeneous surfaces with low cellulose content, whilst rougher surfaces and thicker cross sections were observed in flms with higher cellulose content. Developed biocomposites outperformed biocomposites produced from pristine cellulose powder in terms of homogeneity, thermal stability, antioxidant activity and biocompatibility. Higher cellulose content samples show the formation of a new hydrogen bonding network between PPC and cellulose polymer chains and this contributes to improved thermal stability. TGA results reveal improved thermal stability for high cellulose content films and show enhanced water vapor permeability. A cell viability study shows that the developed materials are biocompatible. Curcumin, a natural antioxidant, was incorporated into optimized biocomposites to produce active biocomposites with antioxidant features to accelerate wound healing. Curcumin is shown to display a sustained release profile over a time period of 3 days, and this is ideal for would healing. The curcumin-functionalized biocomposites also contributed to enhanced thermal stability and water vapor permeability. Thus, these biocomposite films show promise as active biocomposites which can be used for biomedical applications such as wound healing.