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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).

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.

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The principal intention of this work is to fabricate and characterize the polyamide/chitosan nanocomposite by a novel single solvent method through the electrospinning procedure. The thermal properties and morphology of prepared nanocomposite are studied by thermogravimetric analysis (TGA) and eld-emission scanning electron microscopy (FE-SEM). TGA exposed that the primary decomposition temperature is reduced with rising of chitosan content in the nanocomposites and origin disintegration temperature for polyamide/chitosan nanocomposites is perceived to be in the range from 300 to 500°C. Also, FE-SEM images demonstrated that the nano bers of chitosan have good adhesion on the matrix and are well-oriented. Besides, the crystallinity and structural characteristics of the polyamide/chitosan nanocomposites are investigated by using X-ray diffraction (XRD) and Fourier transform-infrared spectroscopy (FT-IR), respectively. The results of XRD proved that the successful blending of chitosan in polyamide is achieved via the electrospinning method. FT-IR results demonstrate that the nano bers are consist of amine groups. Also, the electrical properties of the nanocomposite improved with the increasing content of chitosan and the conductivity of the polyamide/chitosan 5 wt% demonstrates the maximum current of 0.3 nA. Besides, the sheet resistance of the composite reduced 118 to 20 × 10 9 Ω with raising the chitosan volume from 0 to 5 wt%.