Functional properties of nano-SiO2/pinewood-derived cellulose acetate composite film for packaging application

Petroleum-based plastics are widely used because of their practicable properties and low cost. However, people are equally concerned about the environmental damage generated by non-biodegradable petrochemical plastics. In this study, pinewood was employed as the raw material to prepare cellulose acetate and further synthesize the degradable composite films, which showed potential feasibilities to substitute the traditional petroleum-based plastics. In order to improve the barrier performance, hydrophobic performance, and mechanical properties of the film materials, nano-SiO2 was introduced as functional filler for experimental exploration. The tensile strength, light transmittance, water vapor transmittance, microstructure, and crystalline structure of the nano-SiO2/pinewood-derived cellulose acetate composite films were determined by mechanical analysis, optical analysis, SEM, XRD, FT-IR, and barrier characterization methods, respectively. The results exhibited that the prepared films with the inclusion of nano-SiO2 did not conduct reduction in transparency due to its good dispersion in the composite film. The barrier property, hydrophobic performance, and mechanical properties of cellulose acetate composite film were effectively improved due to the interaction between nano-SiO2 and cellulose acetate molecular chains by the hydrogen bonds formed between hydroxyl groups. It was confirmed that the nano-SiO2/pinewood-derived cellulose acetate composite films exhibit great application potential as an environmentally friendly and efficient material for packaging.