The abundance of biological low value sugar beet lignocellulose (SBL) after sugar extraction makes it a potential raw material for biodegradable flexible packaging films. This study attempts to develop a sustainable film from SBL with potential novel applications in packaging. Firstly, the dissertation investigated the effects of chemical pretreatments on the structure and properties of SBL. The study then is focused on improving SBL properties and demonstrating additional applications by developing flexible films with antimicrobial activity.The first objective involved a two-step pretreatment technology to improve the tensile, barrier, and thermal properties of SBL based films. Chemical analyses were used to identify and characterize sugar beet lignocellulose (SBL). Cellulose content of SBL was increased by sulfuric acid pretreatment and bleaching from 22.2% to 80.4%. This was attributed to removal of some lignin, pectin, and hemicelluloses as evidenced by non-destructive spectroscopic analysis. FT-IR spectroscopic analysis of fibers confirmed that the acid pretreatment led to partial removal of hemicelluloses and lignin from the structure of SBL. XRD results revealed that this acid pretreatment resulted in increased crystallinity of the SBL fibers. The thermal gravimetric analysis (TGA) was used to demonstrate the increased thermal stability after acid pretreatment due to the increased contribution of stable cellulose crystals. TGA curves after sulfuric acid pretreatment demonstrated a two-stage thermal degradation behavior due to the introduction of sulfated groups during the sulfuric acid hydrolysis process. These improvements after pretreatments are promising for the use of acid pretreated SBL as a source of bio-based lignocellulose to reinforce polymer composites and high value products from agricultural residues.In the second objective, composite films of pretreated SBL and polyvinyl alcohol (PVOH) plasticized with sorbitol were successfully developed. Film-forming dispersions of different ratios of SBL to PVOH (100/0, 75/25, 50/50, 25/75) were cast at room temperature. Films were evaluated for physical, tensile, water barrier, and thermal properties. The addition of PVOH gave significantly (P≤0.05) higher elongation at break (12.45%) and lower water vapor permeability (1.55 ×10^(-10) g s-1 m-1 Pa-1) than that of control. The ESEM results showed that the compatibility of SBL 50/PVOH 50 was better than those of other composite films. These results suggest that when taking all the studied variables into account, composite films formulated with 50% PVOH are most suitable for various packaging applications.In the third objective, SBL films were developed with cedarwood oil (CWO) and tung oil to improve the water barrier properties and antimicrobial activity. The microstructure of the composite films was characterized through Fourier transform infrared spectroscopy (FTIR). The results showed that cedar and tung oils can be used to decrease water vapor permeability of SBL films by more than 25%; the contact angle to water of SBL film was increased by 134% when incorporated with 15% w/w of tung oil. These results showed the hydrophobicity of the SBL films was increased by adding oils. Antimicrobial properties of the films were improved by the introduction of 5% CWO in the film. Results from antimicrobial tests revealed that the Inhibition Index of cellulosic films increased to 20% by incorporating 20% w/w of CWO. The introduction of oils showed no obvious change in thermal properties.
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