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Lycopene is bequeathed with multiple bio-protective roles, primarily attributed to its unique molecular structure. The concomitant exploitation of two of the green chemistry tools viz., sonication and biocatalysis is reported here for the laboratory scale extraction of lycopene from tomato peel. The coupled system improved the extraction by 662%, 225% and 150% times over the unaided, only cellulase 'Onozuka R-10' treated and only sonication treated samples respectively. The sonication parameters (duration, cycle and amplitude) during the coupled operation were optimized using response surface methodology (RSM). Derivative UV-visible spectra (i.e., dA/dλ and d(2)A/dλ(2) against λ), FTIR analysis, and DPPH scavenging test suggested that the reported extraction protocol did not affect the molecular structure and bioactivity of the extracted lycopene. The influence of sonication on the probable structural modulation (through UV-visible spectral analysis) and activity of the enzyme were also analyzed. A plausible mechanism is proposed for the enhanced extraction achieved via the coupled system.

Biobased hyperbranched poly(ester amide) (HBPEA)/polyaniline (PAni) nanofiber nanocomposites were prepared by incorporating the as-synthesized PAni nanofiber at varied weight percentages by an ex situ polymerization technique. Fourier transform infrared spectroscopic analyses indicated the interactions of the benzenoid–quinoid moieties of PAni with HBPEA. The transition from liquidlike to solidlike behavior of the nanocomposites with a percolation threshold at 10 wt % nanofiber content was studied using dynamic rheology. The formation of nanofibrous network within the HBPEA matrix as vouched for by TEM study and initial degradation temperature (from 277 to 307 °C) was found to be increased with the increment of nanofiber content. The evaluation of mechanical properties such as tensile strength (7.2–12.25 MPa), elongation at break (88–70%), impact resistance (>100 cm), and scratch hardness (8.5–10 kg) together with the decrease in the sheet resistance (from 107 to 105 Ω/sq) forwarded the epoxy–poly(amido amine) cured nanocomposites as prospective antistatic materials.

A facile method of ultrasound-assisted noncovalent functionalization of multiwalled carbon nanotubes (MWCNT) with fatty amide of castor oil and use of the same as a reactive component in the in situ polymerization of hyperbranched poly(ester amide) (HBPEA) via an A 2 + B 2 + A′A 2 approach is reported. The reaction entails anchoring of the amide groups to MWCNT to maximize the reaction with the diacids, resulting in formation of the nanocomposite. Fourier transform infrared analyses validated the anchorage of esteramide groups to the nanotubes. Intercalation and formation of dense polymer layers on the isotropically dispersed nanotubes (with mean coherency coefficient of 0.229) were evident from transmission electron microscopy. The changes in biophysico attributes were reflected in their selective efficacy against the Gram-positive bacteria with an enhanced cytotoxicity (death rate increase of Staphylococcus aureus by 137.5% and Bacillus subtilis by 107.6%) and significant decrease in the sheet resistance by 3 orders of magnitude (from 10 7 to 10 4 Ω sq −1 ) as compared to the pristine HBPEA at low loading of 1 wt % MWCNT. The multifunctional nanocomposites maintained the acceptable mechanical performance, and kinetics evaluation of activation energy revealed enhanced thermal stability over pristine HBPEA; the nanocomposites can be envisaged for MWCNT-based bionano applications, particularly in the field of advanced textiles.

The changes of structure and properties of nanofibers were studied as a function of solubility parameters of the organic solvents that are used in interfacial polymerization of polyaniline (PAni) nanofibers. The presence of UV-visible absorbance at 340, 440, and 800 nm confirmed the formation of emeraldine salt structure of the prepared PAni nanofibers. Fourier transform infrared spectral results indicate an increasing trend of benzenoid to quinoid ratio with the decrease of interaction of the solvents with aniline. This can be correlated to the increase in the degree of conjugation of the polymer chain. Photoluminescence study revealed an increase in the density of defect state with the decrease of interaction. Single-line approximation technique was used to analyze the broadening of the most intense X-ray reflection peak corresponding to (110) plane of the nanofibers. The greater the solvent-monomer interaction, the lesser was the domain length and p-stacking of the PAni chains. The study of this interaction is instrumental to precisely control the internal conformation of the PAni nanofibers. V C 2012 Wiley Periodicals, Inc. J Appl Polym Sci 126: [830][831][832][833][834][835][836] 2012

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