Search for: polymer-layered-silicate-nanocomposites--plsns
Fabrication of “Boron-Clay-Polymer" and "Lead-Clay-Polymer" Nanocomposites for Radiation Shielding of Neutron and Gamma Rays
Sharif University of Technology
In this study, epoxy resin has been modified by nano-clay additives using direct mixing method and epoxy-clay nanocomposites were designed and produced with optimized percentage of clay content. By adding the powder of born carbide and lead oxide in nanocomposites new compounds are obtained. The results are used for protection against neutron and gamma rays, respectively. After preparation of epoxy-clay-born carbide and epoxy- clay-lead oxide nanocomposite the effects of irradiation and carbon fiber on mechanical and thermal properties of nanocomposites were examined. The Nanocomposites were exposed to Electron Beam Irradiation (EBI) in 100 and 500 kGy doses to investigate the effect of...
M.Sc. Thesis Sharif University of Technology ; Alemzadeh, Iran ; Vossoughi, Manuchehr
Nanocomposite films based on low density polyethylene (LDPE), containing of 2, 3, and 4 wt% organoclay (OC) and ethylene vinyl acetate (EVA) copolymer as a new compatibilizer were prepared and characterized using X-ray diffraction, tensile tests, and oxygen permeation measurements. There was no exfoliation or intercalation of the clay layers in the absence of EVA, while an obvious increase in d-spacing was observed when the samples were prepared with EVA present. This issue was reflected in the properties of nanocomposites. The oxygen barrier properties of the OC/EVA/LDPE film were significantly better than those of the OC/LDPE film. The average aspect ratio of clay platelets in...
Incorporating multiscale micromechanical approach into PLSNs with different intercalated morphologies, Article Journal of Applied Polymer Science ; Volume 119, Issue 6 , September , 2011 , Pages 3347-3359 ; 00218995 (ISSN) ; Bagheri, R ; Kazeminezhad, M ; Heidarian, D ; Sharif University of Technology
The objective of the present study is to predict Young's modulus of polymer-layered silicate nanocomposites (PLSNs) containing fully intercalated structures. The particular contribution of this article is to consider the changes in structural parameters of different intercalated morphologies in vicinity of each other. These parameters include aspect ratio of intercalated stacks, number of silicate layers per stack, d-spacing between the layers, modulus of the gallery phase, and volume fraction of each intercalated morphology. To do this, the effective particle concept has been employed and combined with the Mori-Tanaka micromechanical model. It has been shown that the simultaneous effects of...
On the sensitivity of the nanostructural parameters on youngg"s modulus of PLSNs in fully intercalated structures, Article Journal of Composite Materials ; Volume 43, Issue 24 , 2009 , Pages 2921-2941 ; 00219983 (ISSN) ; Bagheri, R ; Kazeminezhad, M ; Sharif University of Technology
Polymer-layered silicate nanocomposites have been observed to demonstrate enhanced mechanical properties particularly at low weight fractions of silicate. Experimental and theoretical investigations reveal that numerous structural parameters strongly influence the modulus of such nanocomposites. A multiscale micromechanical model is developed which considers a wide range of different affecting parameters including the particle aspect ratio, the number of silicate layers per stack, the d-spacing ratio between the layers, the penetration of polymer chains along silicate sheets, the intercalation feature, and the particle volume fraction. The developed model illustrates the accuracy and...