Abstract:

Using microcrystalline cellulose(MCC) and polyvinyl alcohol(PVA) as raw materials, 1-butyl-3-methylimidazole chloride as solvent system, the regenerated cellulose(RGC)/PVA base film was prepared by dissolving and regenerating MCC and blending with PVA. The antibacterial composite film of RGC/PVA/CS/TiO₂ was prepared by coating chitosan(CS) and titanium dioxide(TiO₂) blend solution. The morphology and structure of the composite film were characterized by fourier transform infrared spectrometer, X-ray diffraction and scanning electron microscope, and the thermology, mechanical, optical, barrier and antibacterial properties were tested and analyzed. The results showed that CS and TiO₂ were successfully compounded on the cellulose based film. The thermal decomposition of RGC/PVA/CS/TiO₂ composite film was mainly composed of the decomposition of CS-TiO₂ coating layer and RGC/PVA base film. Compared with the regenerated cellulose film, when the mass fraction of TiO₂ was 0.2%, the tensile strength of the RGC/PVA/CS/TiO₂ composite film increased by 39.28%, the elongation at break increased by 51.66%, light transmittance remained at 88.72%, oxygen transmittance decreased by 47.77% and had a good inhibitory effect on Escherichia coli, Staphylococcus aureus and Bacillus subtilis.

Key words: cellulose, polyvinyl alcohol, chitosan, TiO₂, mechanical properties, optical properties, barrier properties, bacteriostatic properties