Navegando por Autor "Lomonaco, Diego"

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Cashew tree wood flour activated with cashew nut shell liquid for the production of functionalized composites
(Taylor and Francis Group, 2017-06-13) Ito, Edson Noriyuki; Mattos, Adriano Lincoln Albuquerque; Lomonaco, Diego; Rosa, Morsyleide de Freitas; Souza Filho, Men de Sá Moreira de
This work is aimed at the one-step chemical modification of the surface of cashew wood flour particles using the technical grade cashew nut shell liquid (CNSL). The goal is to develop an alternative way to introduce chemically active sites on the surface of the particles, which allows the addition of new functionalities to such particles. The influence of time and temperature and catalyst on the substitution of lignocellulosic hydroxyls with cardanol/cardol urethane derivatives was evaluated by thermogravimetric analysis, scanning electron microscopy, Fourier-transform infrared spectroscopy (FTIR), and contact angle measurements. The mechanical behavior of the modified particles in polypropylene composites was also evaluated by mechanical testing and dynamic mechanical thermal analysis. The FTIR, thermogravimetry, and contact angle results indicated changes on the particle surface, and the mechanical and thermomechanical behavior of the mercerized and modified particles in the composites was found to be similar. These results point that the CNSL approach is a viable way to chemically modify cashew wood flour particle surfaces, while maintaining their properties
A self-assembly of graphene oxide@Fe3O4/metallo-phthalocyanine nanohybrid materials: synthesis, characterization, dielectric and thermal properties
(Springer, 2017-05-01) Costa Júnior, Antonio Eufrazio da; Mota, João Paulo Ferreira; Pontes, Sheyliane Maria Adriano; Maia, Francisco Jonas Nogueira; Clemente, Claudenilson da Silva; Fechine, Pierre Basílio Almeida; Bohn, Felipe; Sales, Antonio Jefferson Mangueira; Sombra, Antônio Sérgio Bezerra; Carbone, Luigi; Mele, Giuseppe; Lomonaco, Diego; Mazzetto, Selma Elaine
In this work, we report the synthesis of novel inorganic–organic hybrid nanomaterials (GO@Fe3O4 /CuPc) and GO@Fe3O4 /ZnPc) consisting of sheets of graphene oxide (GO) decorated by iron oxide nanoparticles (Fe3O4), the whole heterostructure functionalized with metallo-phthalocyanines (MPc, M≡Cu or Zn). First the synthesis of nanomaterial (GO@Fe3O4) was prepared by hydrothermal self-assembly process through the mixture of graphene oxide and Fe+2/Fe+3 salt solution. The metallo-phthalocyanines anchorage on the surface of nanosystem was lately performed by facile and effective ultrasonication method. The structure, composition and morphology of nanohybrids and intermediates were investigated by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, UV–visible spectroscopy, scanning and transmission electron microscopy and impedance spectroscopy. All the results suggested that iron-based nanoparticles were successfully deposited onto graphene oxide sheet networks in the form of Fe3O4, forming nanospheres, decreasing in lattice defects of the GO sheets and dramatically increasing the dielectric properties of nanosystems. Nanomaterials presented saturation magnetization in the 52–58 emu/g and superparamagnetic behavior. It was observed that the values of dielectric constant decreased as a function of the amount of phthalocyanines in the nanomaterials. Therefore, because of their versatile magnetic and dielectric performances, the novel superparamagnetic hybrid nanomaterials, herein described, can be considered as potential for microwave devices

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Navegando por Autor "Lomonaco, Diego"