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In the current research investigation, polycarbonate/hallyosite nanotubes (PC/HNTs) nanocomposite (NC) films have been successfully fabricated by solution intercalation technique using ultrasound energy in facile way which helps complete exfoliation of the HNTs in the matrix. The effect of Gamma irradiation-induced modifications of PC/HNTs NC have been studied in the dose range 200-500 kGy, irradiated with Co60 source. The NC films have been evaluated by UV-visible spectroscopy, Fourier Transform Infrared spectroscopy, X-ray diffraction and scanning electron microscopic techniques in order to probe the effect of gamma radiation on the structural behaviors. The obtained results have been indicated that as the Gamma irradiation dosage increases from 200 to 500 kGy, phenolic group forms through scissoring of ester link of PC, which may cause PC to degrade and lose their property. At lower dosage (200 kGy), the effect is less and at higher dosage (500 kGy), the effect is significant and at 300 and 400 kGy, the effect is moderate and NC films retained their properties. The irradiation effect is most significant and effective at the higher dosage range. UV-visible spectroscopy shows a noticeable reduction in the energy band gap due to gamma irradiation. [ABSTRACT FROM AUTHOR]

ABSTRACT: A series of polyurethane (PU) green composites were synthesized with varying amounts, viz. 0, 2, 4, 8, and 12 wt% of soya protein isolate (SPI). Formation of the urethane linkage in the prepared green composites is revealed by infrared spectroscopy. The glass transition temperature (Tg) of the fabricated PU/SPI composites has been evaluated by differential scanning calorimeter. Thermal stability and degradation analysis of the PU/SPI composites have been performed using a thermogravimetric analyzer (TGA). TGA thermograms clearly revealed that the fabricated composites were thermally stable upto 181°C and show a three‐step of thermal degradation. The water uptake behaviors of PU/SPI systems have been studied at different chemical environments such as distilled water, salt solution, acidic and alkaline solutions. The microcrystalline parameters such as crystallite size (〈N〉) and surface weighted crystal size (Ds) have been evaluated from wide‐angle X‐ray scattering profiles using two different asymmetric distribution functions. PU/SPI green composites were subjected to biodegradation in the presence of Aspergillus niger. The structure–property response of the PU/SPI green composites has been established on the basis of these parameters. [ABSTRACT FROM AUTHOR]

ABSTRACT To know the possibility of using Indian butter tree seed waste (mahua seed cake [MSC]) as a filler in the production of value-added product such as polyurethane (PU) green composites, a series of PU composites have been fabricated with varying amounts, namely, 0, 2.5, 5.0, 7.5, and 10 wt%, of MSC, and their effects on the physicomechanical properties such as density, surface hardness, tensile strength, tensile modulus, and percentage elongation at break have been studied. It was found that the tensile strength of the green composites increased from 5.61 to 9.5 MPa and tensile modulus increased from 4.75 to 6.07 MPa with an increase in filler content from 2.5 to 7.5 wt%. The fabricated PU/MSC composites were characterized for structural behavior by Fourier transform infrared spectroscopy and for morphological behaviors by scanning electron microscopy. The chemical resistance of the green composites in different chemical environments has been investigated. The thermal stability and thermal degradation behaviors of composites were performed using thermogravimetric analysis. The microcrystalline parameters such as crystallite size (< N>) and lattice strain ( g, %) have been computed using wide-angle X-ray scattering data. Based on these parameters, the structure-property relationship of the PU/MSC green composites has been established. [ABSTRACT FROM AUTHOR]

ABSTRACT A series of polyurethane (PU) green composites have been synthesized with varying amounts, namely 0, 2, 4, 8, and 12 wt% of soya protein isolate (SPI) by two methods. In the first method, castor oil (CO) and toluene-2,4-diisocyanate (TDI) molar ratio is CO/TDI : 1/1 with varying amounts of the SPI content. In the second method, the molar ratio of TDI is calculated by considering the -OH groups of both CO and SPI. We made the assumption that, in the first method, SPI acts as a filler and in the second method SPI is one of the coreactants in PU formation. The mechanical properties of the fabricated PU/SPI green composites are evaluated; and it is found that the tensile strength increases up to 8 wt% of SPI, and a further increase in SPI leads to reduction in the tensile strength. The small angle x-ray scattering profiles have been used to evaluate the arrangement of amorphous (A) and crystalline (C) regions in the PU/SPI green composites in a scale of about 700 Ǻ by considering the variation in scattered intensity with scattering angles ranging from 0.3° to 1.5°. For this purpose, a linear paracrystalline model is used. In this study, the exponential distribution of phase lengths gives a good agreement between the measured and computed data on the basis of a linear paracrystal model. It is observed that there are significant changes in the distribution of phase lengths due to changes in the composition and chemical structure of PU/SPI composites obtained by methods 1 and 2. [ABSTRACT FROM AUTHOR]

ABSTRACT A series of castor oil (CO)-based polyurethanes (PUs) were prepared by reacting CO with toluene diisocyanate (TDI) in the presence of coconut oil (CCO). The effects of CCO content viz., 5, 10, 20, and 30 wt% on the physico-mechanical properties and chemical structure of PUs have been evaluated. The mechanical properties of the PUs indicate that the incorporation of CCO improves the tensile behaviors. The swelling behaviors of the PUs have been studied in organic solvents. The microcrystalline parameters, such as crystal size (< N>) and lattice disorder ( g), of PUs have been estimated using wide-angle X-ray scattering studies. The results of tensile behaviors were corroborated with the microcrystalline parameters of the PUs. For a holistic view of the parameters involved in these systems, we have carried out the multivarient analysis that gives a better perspective of the result. © 2013 Wiley Periodicals, Inc. Adv Polym Technol 2014, 33, 21390; View this article online at . DOI 10.1002/adv.21390 [ABSTRACT FROM AUTHOR]

Herein we have synthesised Gadolinium oxide doped Zinc oxide (Gd2O3@ZnO) by solution combustion method and incorporated it as a nano-filler into Polyvinyl alcohol (PVA) polymer matrix using solution intercalation technique to get PVA/Gd2O3@ZnO nanocomposite film. The X-ray diffraction (XRD), Scanning electron microscopy, Differential scanning calorimetry (DSC) and UV–Vis spectroscopy were used to investigate the structural, morphological, glass transition temperature and optical properties of synthesized nanocomposites respectively. The optical properties of PVA/Gd2O3@ZnO film shows the interaction of –OH groups in PVA and dopant. From DSC, it is clear that Tg of prepared nano-composites increases with increasing in dopant concentration. XRD analysis showed that the crystalline characteristics of the nanocomposites increases with increase in dopant concentration. The UV–Visible spectra reveals that there is decrease in indirect band gap of PVA from 4.94 to 3.12 eV and direct band gap from 4.90 to 3.03 eV compared to pristine PVA Gd2O3@ZnO doped nanocomposite films showed multi-fold enhancement in optical characteristics such as refractive index of PVA doped nanocomposites compared pristine PVA, optical conductivity, finess coefficient, extinction coefficient on increasing in dopant concentration (0%, 2%, 4%, 6% and 8 wt%).The optical characteristics of PVA/Gd2O3@ZnO nanocomposite films show excellent UV-blocking behaviour suggesting that, they are promising materials for optical devices. [ABSTRACT FROM AUTHOR]

Calcium ferrite compounds with two different kinds of structures have been produced by two synthesis approaches. The structural analysis is established by Rietveld refinement of X-ray diffraction patterns for Spinel CaFe2O4 and Brownmillerite Ca2Fe2O5. Scanning Electron Microscopy studies ascertain the morphological properties. Fourier Transform Infrared Spectroscopy deduces band stretching of tetrahedral and octahedral sites for ferrite specimens. The bandgap energies are estimated for prepared samples using Tauc relation from ultraviolet visible diffusion reflectance spectroscopy. The methylene blue dye degradation has been studied using prepared ferrite photocatalysts. Brownmillerite with high surface area is offered more sites for the adsorption process, and hence degradation rate is faster than that of Spinel. [ABSTRACT FROM AUTHOR]

Polyurethane (PU) is one of the important industrial polymers. PU and its composites can be used in different applications. This paper examines the potential of PU/copper sulphide (CuS) nanocomposites (NCs) for application as green mulching films in agriculture. Castor oil-based PU NCs were fabricated by varying the CuS concentration viz., 0.0%, 1.0%, 2.0%, 4.0% and 8.0%. The NCs were characterised for microcrystalline nature by X-ray diffraction, Fourier transform infrared spectroscopy used for examining spectral characteristics, morphological assessment by scanning electron microscopy and elemental analysis by energy-dispersive x-ray Spectroscopy. The NCs were characterised for tensile properties, which revealed that a 4% PU/CuS nanocomposite (NC) exhibited high elongation at break of 399.72 MPa, suitable for mulching applications. Thermogravimetric analysis was used to examine the thermal stability and degradation. The chemical resistance and water absorption were evaluated in various atmosphere. The biodegradability was investigated through the soil and cow dung burial test. The pot study experiment is conducted to investigate the effect of NC on growth rate of the plants, which showed that beans treated with PU/CuS NC showed a 43% increase in height within 7 days and a 32% increase within 35 days, with an increase of about 62.5% in leaf width within 7 days and continues to increase until the 35th day and shows considerably more branches and stem diameter than the control. This work concludes that PU/CuS NCs have high potential as green mulching films for application in agriculture.Graphical abstract: Polyurethane (PU) is one of the important industrial polymers. PU and its composites can be used in different applications. This paper examines the potential of PU/copper sulphide (CuS) nanocomposites (NCs) for application as green mulching films in agriculture. Castor oil-based PU NCs were fabricated by varying the CuS concentration viz., 0.0%, 1.0%, 2.0%, 4.0% and 8.0%. The NCs were characterised for microcrystalline nature by X-ray diffraction, Fourier transform infrared spectroscopy used for examining spectral characteristics, morphological assessment by scanning electron microscopy and elemental analysis by energy-dispersive x-ray Spectroscopy. The NCs were characterised for tensile properties, which revealed that a 4% PU/CuS nanocomposite (NC) exhibited high elongation at break of 399.72 MPa, suitable for mulching applications. Thermogravimetric analysis was used to examine the thermal stability and degradation. The chemical resistance and water absorption were evaluated in various atmosphere. The biodegradability was investigated through the soil and cow dung burial test. The pot study experiment is conducted to investigate the effect of NC on growth rate of the plants, which showed that beans treated with PU/CuS NC showed a 43% increase in height within 7 days and a 32% increase within 35 days, with an increase of about 62.5% in leaf width within 7 days and continues to increase until the 35th day and shows considerably more branches and stem diameter than the control. This work concludes that PU/CuS NCs have high potential as green mulching films for application in agriculture. [ABSTRACT FROM AUTHOR]