Assessment of mechanical and healing behaviors of glass fibers-epoxy composite containing the microcapsules with the nanocomposite shell

In the current study, the effect of adding the encapsulated healing agent with neat polymeric and nanocomposite shells on the mechanical-healing features of glass fibers/epoxy composite under various loads was investigated. Therefore, the microcapsules with urea-formaldehyde (UF) nanocomposite shell containing the various weight fraction of silica nanoparticles (0, 1, 2, 3) were synthesized. After that, the flexural, tensile, and interlaminar shear strength (ILSS) samples were destructed by using the quasi-static penetration method with the damaging force of 500, 1050, and 2900 N, respectively. The maximum healing efficiency in the flexural loads belonged to the composite with the 3 wt% nanosilica on the surface of microcapsules, which was 83.9%. Also, it was found the increment in the weight fraction of silica nanoparticles had a negligible effect on the healing ability of composite under tensile loading. Achieving 135.8% healing efficiency in the composite with the 2 wt% nanosilica under the shear loads can be one of the most important findings in this work.     

Synthesis of Clay/Poly (styrene/2-ethylhexyl acrylate) Nanocomposite Latexes via Emulsion Polymerization

Silicon - In this research, nanocomposite latex based on polystyrene-co-2-ethylhexyl acrylate with layered silicate was synthesized by emulsion polymerization procedure. For increasing...     

Study of wear resistance and nanostructure of tertiary Al<Subscript>2</Subscript>O<Subscript>3</Subscript>/Y<Subscript>2</Subscript>O<Subscript>3</Subscript>/CNT pulsed electrodeposited ni-based nanocomposite

We study the electrodeposition of tertiary Alumina/Yitria/carbon nanotube (Al₂O₃/Y2O₃/CNT) nanocomposite by using pulsed currents. The process of coating is performed in a nickel-sulfate bath and the nanostructure of the obtained compound layer is examined with the help of high-precision figure analysis of SEM nanographs. The effects of process variables, i.e., the Y₂O₃ concentration, treatment time, current density, and the temperature of electrolyte are experimentally investigated. Statistical methods are used to achieve the minimum wear rate and average size of nanoparticles. Finally, the percentage contributions of different effective factors are revealed, and the confirmation run showed the validity of the obtained results. It is also revealed that the wear properties of the coatings undergo significant changes if the sizes of nanoparticles change. The atomic-force microscopy (AFM) and transmissionelectron microscopy (TEM) analyses confirm the smooth surfaces and average sizes of nanoparticles in the optimal coating.