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The current study deals with the preparation and characterization of polysaccharide‐based biocomposite films acquired by the incorporation of cellulose nanofiber within glycerol plasticized matrix formed by starch. The application of starch‐based films is restricted owing to highly hydrophilic nature and poor mechanical properties. These problems are solved by forming a nanocomposite of thermoplastic starch (TPS) as matrix and cellulose nanofiber (CNF) as reinforcement. CNF is successfully synthesized from short pure cellulose fibers by a chemo‐mechanical process. TPS/CNF composite films are prepared by the polymer solution casting method, and their characterizations are obtained by water vapor transmission rate, differential scanning calorimetry (DSC), atomic force microscopy (AFM), oxygen transmission rate, X‐ray diffraction (XRD), light transmittance, and tensile test. Even at the low concentration of CNF filled TPS, the composite film shows improvement in properties. The 0.4 wt% CNF loaded TPS films show approximately the maximum improvement in tensile strength. Above 0.5 wt% CNF, tensile strength starts to deteriorate. Water vapor transmission rate (WVTR) and oxygen transmission rate (OTR) results show improvement in water vapor barrier properties of TPS matrix. The DSC thermograms of TPS and composite films do not show any significant effect on the melting point of the composite film compared with the base polymer TPS. The AFM analysis shows the topography of the surface of the nanocomposite. The morphology of nanofibers is studied by using the scanning electron microscopy (SEM) and the transmission electron microscopy (TEM).

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Starch nanoparticles (SNPs) are synthesized by different precipitation techniques using corn starch, and SNP films are prepared by the evaporation casting method. The morphological study is investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The distribution and sizes of precipitated SNPs after synthesizing are discovered by these methods as well. The crystallinity of the SNPs is studied by the X-ray diffractometry (XRD) method that demonstrates reduction compared to neat starch granules, and it is changed from A-style to V H -style after precipitation. The chemical bonding of different SNPs after the nanoprecipitation is analyzed by Fourier transform infrared spectroscopy (FT-IR). Thermogravimetric analysis (TGA) demonstrates the decomposition of starch nanoparticles and the starch matrix that is related to the depolymerization of carbon chains in the range of 260 to 350 °C. The mechanical properties of the SNP films versus the temperature changing are discovered by dynamic mechanical analysis (DMA). The water contact angles of SNP films are measured using a goniometer, and the results showed the hydrophobic surfaces of the prepared films. Our study indicates that SNPs have a promising impact on the properties of corn starch films, which would be useful in biodegradable packaging material.

The cellulose nanofibers (CNF) are novelly extracted via air plasma treatment combined with the ultrasonication procedure. This study prepares and characterizes the starch‐based biocomposites reinforced by CNF within the glycerol plasticized matrix. The application of starch‐based polymers is improved with fabricating a biocomposite of thermoplastic starch (TPS) as matrix and the CNF as reinforcement. After modifying the surface of the cellulose fibers (CF) by air plasma treatment, CNFs are extracted by using an ultrasonic bath. The CNF are studied using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy. The TPS/CNF composites are prepared using the high‐friction and hot‐compression procedure. Tensile test results and SEM images of the fracture surfaces show significant improvement of adhesion between CNF and TPS matrix compared to composites reinforced by neat CF. The thermogravimetric analysis shows a considerable decompositionat approximately 270–340°C.

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