نوع مقاله : مقاله کامل علمی پژوهشی
نویسندگان
1 دانشجوی دکتری صنایع چوب و فرآورده های سلولزی، دانشکده منابع طبیعی، دانشگاه زابل، زابل، ایران
2 دانشیار، گروه صنایع چوب و فرآورده‌های سلولزی ، دانشکده منابع طبیعی، دانشگاه زابل، زابل، ایران.
3 دانشیار، گروه تکنولوژی و مهندسی چوب، دانشکده مهندسی چوب و کاغذ، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران.
4 دانشیار ، گروه صنایع چوب و فرآورده‌های سلولزی، دانشکده منابع طبیعی، دانشگاه زابل، زابل، ایران.
5 استادیار، گروه عمل آوری محصولات شیلاتی، دانشکده شیلات و محیط‌زیست، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران.
6 استاد، گروه شیمی، دانشکده شیمی، دانشگاه کوبه، کوبه ،ژاپن.
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Background and objectives: In recent years, the development of biodegradable and environmentally friendly materials for packaging applications has attracted significant attention due to growing environmental concerns and the different limitations associated with the use of synthetic polymers. Bio-nanocomposites have been introduced as sustainable alternatives for food packaging. Among them, bio-nanocomposites composed of cellulose nanofibers as the reinforcing phase and chitosan as the matrix phase have gained considerable interest owing to their unique characteristics, including renewability, biodegradability, biocompatibility, and antibacterial properties. Cellulose nanofibers, due to their high mechanical strength and ability to form network structures, play a crucial role in enhancing the mechanical and barrier properties of packaging films. On the other hand, the chitosan matrix contributes antimicrobial and antioxidant properties, which are essential for extending the shelf life of food products and reducing spoilage. Therefore, the combination of these two nanomaterials can lead to the fabrication of a bio-nanocomposite with suitable mechanical and physical performance and high potential for food packaging applications. In this study, an innovative method (partial dissolution) was employed to facilitate the fabrication of a cellulose nanofiber–chitosan bio-nanocomposite, followed by the characterization of the resulting specimens in terms of their physical, mechanical, and antibacterial properties.
Materials and methods: In this study, two types of raw materials were used: cellulose nanofiber gel and chitosan nanofiber gel, both supplied by Nanonovin Polymer Company. Prior to the fabrication process of the bio-nanocomposites, the exact concentration of each gel was determined, and based on predefined ratios, the various combinations of the gels were prepared. The gels were mixed with a specific amount of distilled water and homogenized using a magnetic stirrer to obtain a uniform suspension. This homogeneous mixture was then transferred to a vacuum filtration system for nanopaper fabrication. Once the initial nanopaper mat was formed, it was removed from the apparatus and dried completely in a vacuum oven at 70 °C for 24 h. In the subsequent step, these pure and hybrid raw nanopapers were transformed into cellulose nanofiber–chitosan bio-nanocomposites using a dissolution method. For this purpose, the specimens were immersed in a 0.5% acetic acid solution for 4 minutes and then neutralized using a 1% NaOH solution. After stabilizing the physical structure through multiple washing steps with distilled water, the samples were thoroughly dried. Finally, in order to evaluate the properties of the fabricated nanopapers and bio-nanocomposites, several tests were conducted, including X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), fourier transform infrared (FTIR) spectroscopy, static tensile, and antibacterial activity assessment.
Results: The results showed that the integration of cellulose nanofibers and chitosan nanofibers significantly enhanced the structural and functional properties of the fabricated nanopapers and bio-nanocomposites. XRD and FTIR analyses confirmed the successful formation of chemical bonds between the composite components and the development of a crystalline structure suitable for the formation of reinforcing and matrix phases. The FE-SEM micrographs revealed that both cellulose and chitosan nanofibers were within the actual nanoscale range (1-100 nm) and that cellulose nanofibers were uniformly dispersed within the chitosan matrix as the reinforcing phase. So that the nanobiocomposite obtained from the combination of 70% nanofiber cellulose and 30% nanofiber chitosan increased by 25.6 and 94.8% compared to the pure nanopapers obtained from nanofiber cellulose and nanofiber chitosan, respectively. In addition, the results of the antimicrobial test (colony count method) showed that the prepared nanobiocomposites have an effective inhibitory property against pathogenic bacteria, which can increase the shelf life of food.
Conclusion: Overall, the innovative method employed for the fabrication of cellulose–chitosan bio-nanocomposites was successfully implemented, and the resulting materials demonstrated great potential as alternatives to conventional packaging materials.
کلیدواژه‌ها [English]
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