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Polyurethane nanocomposites with varying concentration of different fillers are produced through hot melt extrusion by using nanotalc and Cloisite 30B as fillers. The TEM images show good dispersion of 30B while moderate agglomeration in nanotalc composite. The result is supported by the respective nanostructures (exfoliated in 30B vs. intercalated in nanotalc composites). A slight decrease in degradation temperature is observed but the nanocomposites are thermally stable upto 300°C. Permeability significantly decreases for nanocomposites. Young's modulus increases with increasing filler concentration while the toughness improvement exhibits a maximum at 4 and 6 wt% of 30B and nanotalc, respectively. Halpin–Tsai model is employed to predict the mechanical properties of the composites. The mechanical, thermal and gas barrier properties are better in 30B as compared to nanotalc nanocomposites, due to greater interaction in 30B nanocomposites evident from the large shift of peak position in UV–vis and FTIR measurements along with its good dispersion. [ABSTRACT FROM AUTHOR]

Amorphous poly(ethylene terephthalate) (PET)/nanotalc nanohybrids have been prepared through solution casting route. The fine dispersion of nanotalc clay in the polymer matrix has been examined through transmission electron microscopy (TEM). The intercalation and interaction of nanoclay have further been confirmed using X‐ray diffraction, ultraviolet, and Fourier transform infrared techniques. The thermal stability has been tested via thermogravimetric analysis and nanohybrids have been found thermally stable. The glass‐transition temperature has been further confirmed through DTA and differential scanning calorimetry analysis which has been increased in the presence of nanotalc arising from greater interaction. The nanohybrids have been tested for their mechanical performances and have been found to have improved mechanical responses for nanotalc‐filled nanohybrids. The modulus has been increased whereas toughness has been compromised meagerly. The modulus values have been theoretically predicted using various micromechanical models. The microhardness of the nanohybrids has been examined through Vicker hardness test. The theoretical prediction of the hardness values has been done using different micromechanical models. The structural development upon uniaxial stretching of the samples has been studied using small‐angle X‐ray scattering and wide‐angle ray diffraction. The stretched samples have found to have short‐range ordering as well as increased blob size and better coherency in the presence of nanotalc. The aspect ratio has been increased upon stretching. The inclusion of nanotalc has induced high barrier for gas permeation as compared to pure PET. The oxygen transmission rate has been found to decrease up to 64% for 8 wt % of filler concentration. The prediction of the permeability data has been done using different models considering different aspect ratios. The permeability values have been predicted very closely and nanohybrids have been found suitable for practical applications such as packaging. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 137, 48607. [ABSTRACT FROM AUTHOR]

Active packaging is one of the interesting concepts in food industry which extend the shelf-life of the food products. The purpose of this work was to develop nontoxic antimicrobial nanocomposite films. Benzyltrimethylammonium chloride modified montmorillonite (BMMT) were used as nano-filler and the prepared BMMT was characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermogravimetric analysis. Polyethylene glycol (PEG) plasticized cellulose acetate butyrate (CAB) films with different ratios of PEG and CAB was prepared and it was found that the 20 wt% PEG in CAB matrix (CBP 20 ) gave optimal results in terms of mechanical properties. BMMT was mixed with CBP 20 in different proportions to prepare nanocomposites. 3 wt% BMMT loaded nanocomposite gave best in terms of the barrier and mechanical properties. The storage modulus, thermal stability, glass transition, and melting temperature of the nanocomposites increased with the loading of 1, 3, and 5 wt% of BMMT. Furthermore, these nanocomposites showed nontoxic and antimicrobial behavior. [ABSTRACT FROM AUTHOR]

Films based on methylcellulose (MC) and pectin (PEC) of different ratios were prepared. MC/PEC (90:10) (MP 10 ) gave the best results in terms of mechanical properties. Sodium montmorillonite (MMT) (1, 3 and 5 wt%) was incorporated in the MP 10 matrix. The resulting films were characterized by X-ray diffraction and transmission electron microscopy, and it was found that nanocomposites were intercalated in nature. Mechanical studies established that addition of 3 wt% MMT gave best results in terms of mechanical properties. However, thermo-gravimetric and dynamic mechanical analysis proved that decomposition and glass transition temperature increased with increasing MMT concentration from 1 to 5 wt%. It was also observed that moisture absorption and water vapor permeability studies gave best result in the case of 3 wt% MMT. Optical clarity of the nanocomposite films was not much affected with loading of MMT. In vitro drug release studies showed that MC/PEC/MMT based films can be used for controlled transdermal drug delivery applications. [ABSTRACT FROM AUTHOR]

Highlights: [•] Formation of GO is confirmed by XRD, FTIR and Raman spectral analysis. [•] HPMC/GO nanocomposites are developed. [•] XRD and SEM establish the formation of exfoliated HPMC/GO nanocomposites. [•] Enhancements in mechanical and thermal properties of nanocomposites are observed. [•] Moisture absorption and WVTR of HPMC film are declined with GO loading. [ABSTRACT FROM AUTHOR]

Highlights: [•] Mucilage was extracted successfully from Colocasia esculenta (Taro) corms. [•] Drug loaded mucilage/HPMC based transdermal patch were prepared and characterized. [•] Presence of mucilage in transdermal patches increased in vitro release time. [•] Skin irritation test showed patches were free of potentially skin irritation. [ABSTRACT FROM AUTHOR]

Abstract: Nanocomposites of poly(vinyl alcohol) (PVA), poly(vinyl pyrrolidone) (PVP) and sodium montmorillonite (Na+MMT) were prepared by solution mixing and then cast into films. X-ray diffraction analysis and images of transmission electron microscopy establish the formation of PVA/Na+MMT intercalated nanocomposite. Exfoliated and highly intercalated PVA/PVP/Na+MMT nanocomposite formed in the presence of PVP. Inclusion of PVP in PVA/Na+MMT matrix enhances the hydrogen bonding interactions between PVA and Na+MMT and thus increases the mechanical properties and thermal stability of PVA/PVP/Na+MMT nanocomposites compared to PVA/Na+MMT nanocomposite. The interactions between PVA, PVP and Na+MMT were established by the Fourier transform infrared spectroscopy. The moisture absorption tendency of both the PVA and PVA/PVP films reduced after the incorporation of Na+MMT at 75% constant relative humidity. Differential scanning calorimetry studies show that the presence of PVP and Na+MMT both are responsible for reducing the heat of fusion, and crystallinity of PVA. The flow behavior of the PVA, PVA/PVP and its nanocomposite solutions has been also studied. Water vapor permeability of PVA/PVP/Na+MMT composite films decreased in the presence of nanoclay due to increasing tortuous paths for diffusion. [Copyright &y& Elsevier]

Highlights: [•] HPMC/MMT nanocomposites are developed. [•] XRD and TEM establish partly exfoliated and intercalated HPMC/MMT nanocomposites. [•] Mechanical and thermal properties of nanocomposites are improved. [•] Moisture absorption and WVTR of HPMC film is reduced with loading of MMT. [•] Optical clarity of HPMC film is almost unaffected in presence of MMT. [ABSTRACT FROM AUTHOR]