Browsing by Author "Varela Caselis, Jenaro Leocadio"

Now showing 1 - 3 of 3
  • Artículo
    Effect of addition of non-functionalized graphene oxide in a commercial epoxy resin used as coating
    (2022-02-28) Varela Caselis, Jenaro Leocadio; Santamaría Juárez, Juana Deisy; Galicia Aguilar, José Alberto; Domínguez Alcalá, María Fernanda; Rubio Rosas, Efraín; Mendoza Hernández, José Carlos; Sánchez Cantú, Manuel; Varela Caselis, Jenaro Leocadio; 0000-0001-5029-7701; Santamaría Juárez, Juana Deisy; 0000-0003-0935-5468; Galicia Aguilar, José Alberto; 0000-0001-7079-5134; Rubio Rosas, Efraín; 0000-0002-2300-8529; Mendoza Hernández, José Carlos; 0000-0003-2539-8177; Sánchez Cantú, Manuel; 0000-0003-2044-893X
    "The paper studies the effect of incorporating graphene oxide (GO) without surface functionalization on a commercial epoxy resin. GO was dispersed in a commercial epoxy resin at concentrations of 0 wt.%, 0.1 wt.%, 0.5 wt.%, 1 wt.%, and 3 wt.%. The resultant materials were deposited on carbon steel substrates, followed by the use of a 5 wt.% aqueous NaCl electrolyte, to evaluate the effectiveness of their anticorrosive coating function. Scanning electron microscopy (SEM) analysis showed that the GO was homogenously dispersed in the polymer matrix, resulting in flat a nd s mooth s urfaces. T he X -ray diffraction (XRD) results showed that although GO was highly dispersed in the polymer matrix, multilayer graphene was also obtained after curing. The anticorrosive properties were evaluated by electrochemical impedance spectroscopy (EIS) at various exposure periods. Analysis of the prepared samples indicated that the best anticorrosion performance among them was available with the 0.5 wt.% GO coating. The obtained results indicate that GO–polymer matrix composites provide improved corrosion protection properties even after 500 h exposure to the NaCl solution".
  • Artículo
    Phenolic resin-commercial graphite disk preparation: Effect of the resin amount and the thermal treatment on the structural, morphological and mechanical properties
    (2019-09) Santamaría Juárez, Juana Deisy; Galicia Aguilar, José Alberto; Vargas Galarza, Zully; Varela Caselis, Jenaro Leocadio; Sánchez Cantú, Manuel; Santamaría Juárez, Juana Deisy; 0000-0003-0935-5468; Galicia Aguilar, José Alberto; 0000-0001-7079-5134; Vargas Galarza, Zully; 0000-0002-5429-0897; Varela Caselis, Jenaro Leocadio; 0000-0001-5029-7701; Sánchez Cantú, Manuel; 0000-0003-2044-893X
    "In this work, macroporous discs were prepared using synthesized phenolic resin (PR) and commercial graphite mixtures (15–40 weight percent). The structure of the PR resin was confirmed by Proton Nuclear Magnetic Resonance and Gas Chromatography Coupled to Mass Spectrometry while the curing temperature was determined by Fourier Transform Infrared Spectroscopy. Also, the surface homogeneity and the structural analysis of the prepared disks were examined by means of scanning electron microscopy and X-ray powder diffraction analysis, respectively. According to the micrographs it was observed that as the PR amount increased disks’ porosity decreased giving rise to homogeneous and smooth surfaces which was explained in terms of the X-ray diffraction analysis that proved that graphite average crystal size (ACS) values decreased progressively with PR amount. Furthermore, it was demonstrated that the mechanical resistance could be tuned with the PR amount and the thermal treatment since as both increased the disks’ hardness augmented".
  • Artículo
    Synthesis and characterization of AN/EGDMA-based adsorbents for phenol adsorption
    (2017-08) Galicia Aguilar, José Alberto; Santamaría Juárez, Juana Deisy; López Badillo, Maribel; Sánchez Cantú, Manuel; Varela Caselis, Jenaro Leocadio; Galicia Aguilar, José Alberto; 0000-0001-7079-5134; Santamaría Juárez, Juana Deisy; 0000-0003-0935-5468; Sánchez Cantú, Manuel; 0000-0003-2044-893X; Varela Caselis, Jenaro Leocadio; 0000-0001-5029-7701
    "In this work, acrylonitrile (AN)/ethylene glycol dimethacrylate (EGDMA) cross-linked polymeric adsorbents were synthesized by the suspension polymerization method. The adsorbents were prepared varying the EGDMA cross-linker ratio from 100 to 60%. It was found that the swelling factor and the specific surface area changed inversely with the crosslinking degree. In addition, the thermal characterization indicated that polymers stability increased as the crosslinking degree decreased. The polymers were tested as phenol adsorbents and it was found that the higher uptake level was reached when the acrylonitrile concentration increased in the polymer. Adsorption isotherm was determined fitting the Langmuir model, indicating a homogeneous surface of the adsorbents. Moreover, the kinetic studies indicated that the rate controlling step corresponded to the intraparticle diffusion since adsorption is promoted when the adsorbent is swollen".