Avaliação de filmes híbridos de quitosana/nanofibrila de celulose e TiO2 para embalagens flexíveis

Abstract

The search for the development of smart sustainable packaging produced using renewable raw materials is constantly increasing not only because of environmental issues, but also because of the growing demand for fresher and minimally processed foods. Therefore, the use of biopolymers such as chitosan (Q) and cellulose nanofibril (NFC) has a high potential in the development of biodegradable films replacing conventional plastics from fossil fuels such as petroleum. Cellulose nanofibril is used as a reinforcing material, increasing the mechanical strength of the films. In addition, other compounds can be added to the base of the films, whether organic or inorganic, in order to improve or even generate other properties such as, for example, antimicrobial and antioxidant action. Thus, TiO2 has been studied as a component that, when incorporated into chitosan/cellulose nanofibril films, promotes bacterial inhibition. In this research, hybrid films of Q/TiO2/NFC were prepared at different concentrations to evaluate their potential for application in food packaging. The characterization of the films was made by thermogravimetric analysis (TAG), Infrared (FTIR), Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD). Physical-chemical properties, moisture, water vapor permeability, optical properties, antioxidant and antibacterial action of the films were also analyzed. The results showed that the incorporation of NFC and TiO2 were efficient to improve the properties of the films as there was a decrease in moisture (control film Q1: 21.34; hybrid Q1T6N5: 14.59) of the water vapor permeability (control film : Q1,5: 3.09 x 10-14 ; hybrid: 2.35 x 10-14 ), making them more resistant. Furthermore, through the characterizations it was possible to observe that there was physical interaction between the constituents in the film samples. The addition of TiO2 showed satisfactory results, as it inhibited the propagation of the two bacteria under study (E. coli and S aureus) in some films. While the Q1 control film did not inhibit S aureus proliferation, the Q1T2N1 hybrid showed a 9.0 mm inhibition halo. Therefore, the hybrid material produced proved to be promising for the development of active sustainable food packaging.