Swarnalata Sahoo^1,2*, Hemjyoti Kalita¹, Smita Mohanty^1,2, Sanjay Kumar Nayak^1,2

Journal of Renewable Materials, Vol.6, No.1, pp. 117-125, 2018, DOI:10.7569/JRM.2017.634155

Abstract In the current work, we have synthesized vegetable oil-based polyurethane-OMMT clay nanocomposite (PUNC) adhesive with the incorporation of different wt% of organically modified nanoclay (1 to 5 wt%) into the biobased polyurethane (PU) matrix through in-situ polymerization process via ultrasonication method. At the initial stage, PU adhesive was prepared using polyol and partially biobased aliphatic isocyanate, wherein polyol was derived from the transesterified castor oil using ethylene glycol. The formation of PU and PUNC adhesive was confirmed using Fourier transform infrared (FTIR) spectroscopy analysis. The tensile strength of PU with different wt% of nanoclay was determined and the analysis showed… More >

Juan P. Correa^1,2*, Alejandro Bacigalupe^2,3, Jorge Maggi⁴, Patricia Eisenberg^2,3

Journal of Renewable Materials, Vol.4, No.4, pp. 258-265, 2016, DOI:10.7569/JRM.2016.634117

Abstract Poly(lactic acid)/poly(butylene adipate-co-terephthalate) (PLA/PBAT)-based nanocomposites were prepared by melt blending of PLA and PBAT with 5 wt% of unmodified (Cloisite Na) and modified (Cloisite 30B) montmorillonites. X-ray diffraction (XRD) revealed an intercalated structure in both nanocomposites. The extent of the intercalation was higher for nanocomposites based on modified clays (OMMT) with chemical affinity with the polymer matrix. Rheological measurements have shown an increase in viscosity and a better degree of clay dispersion for nanocomposites containing OMMT. Nanocomposites with OMMT showed lower PBAT separated phase particle size and improvements in thermal stability, mechanical properties and water vapor barrier when compared with… More >

Kunigal N.Shivakumar¹, Shivalingappa Lingaiah², Robert Sadler², Matthew Sharpe²

CMC-Computers, Materials & Continua, Vol.1, No.4, pp. 309-318, 2004, DOI:10.3970/cmc.2004.001.309

Abstract The exfoliation and dispersion of nanoclay (2% by weight) and nanovermiculite (2% by weight) particles in a polymer matrix is analyzed using the Scanning Electron Microscope (SEM) after a low temperature air plasma etch. The plasma etch preferentially removes the polymer to expose the nanoparticles. Both Argon and air have been used as the etching media to study the etching process. SEM analysis illustrate the results of the etching in flat and edge surfaces of both nanoclay (MMT) and nanovermiculite (VMT) filled polymer. Both the MMT and VMT were dispersed using a IKA high shear mixer and a Sonicator. More >

D.M. Zhang^1,2, L.X. Ma^1,2, H.W. Huang^1,2, J. Zhang^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.89, No.3, pp. 163-188, 2012, DOI:10.3970/cmes.2012.089.163

Abstract This paper suggests a new set of analytical solutions for predicting leakage-induced seepage field and ground settlement in saturated clay. A unique feature of the solutions presented is considering the effect of the tunnel lining through the relative permeability between the tunnel and the soil. Through the superposition method, the proposed method can be easily extended to twin parallel tunnels. The accuracy of the analytical solutions are verified with numerical simulations. Parametric studies reveal that the decrease of pore pressure and the consequent settlements of ground and tunnel is proportional to the relative permeability. Over 20% of the initial hydrostatic… More >

A.P.S. Selvadurai¹, H. Ghiabi²

CMES-Computer Modeling in Engineering & Sciences, Vol.23, No.1, pp. 53-74, 2008, DOI:10.3970/cmes.2008.023.053

Abstract This paper deals with the problem of the consolidation of a composite consisting of alternate layers of soft clay and a granular material. A series of experiments were conducted on components to develop the constitutive models that can be implemented in a computational approach. The constitutive response of the soft clay is represented by a poro-elasto-plastic Cam clay-based model and the granular medium by an elasto-plastic model with a Drucker-Prager type failure criterion and a non-associated flow rule. The computational poro-elasto-plastic model is used to calibrate the experimental results derived from the one-dimensional tests and to establish the influence of… More >

A. K. Plappally^1,3, I. Yakub^2,3, L. C. Brown^1,2,3, A. B. O. Soboyejo¹

FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.4, pp. 373-398, 2009, DOI:10.3970/fdmp.2009.005.373

Abstract Water flow through point-of-use porous ceramic water treatment filters have been theoretically analyzed in this technical paper. Filters tested were manufactured by combining low cost materials namely, clay and sawdust. Three filters with distinct volume fractions of clay to sawdust (75:25, 65:35 and 50:50) were tested. Sintered clay filters casted in frustum shapes were structurally characterized using mercury intrusion porosimetry. A linear increase in porosity with volume fraction of sawdust was observed. Flow experiments were carried out at constant room temperature and pressure. Potable tap water was used in these studies. Flows through filters occurring with drop in the head… More >

S. Smaoui¹, A. Ben Hamida¹, I. Djeran-Maigre², H. Dumontet¹

CMC-Computers, Materials & Continua, Vol.4, No.3, pp. 153-162, 2006, DOI:10.3970/cmc.2006.004.153

Abstract An iterative homogenization approach is proposed in order to predict the nonlinear hydro-mechanical behaviour of porous media. This process is coupled to classical and modified secant extended methods and linear homogenization predictive schemes. At convergence of the iterative process, same equivalent behaviour is obtained for any secant method, any simplified homogenization used for the linear comparison material and for any initial porosity of the media. An application to the study of the nonlinear behaviour of clayey sediments is presented. The model parameters quantification is based on oedometric experimental results for different clays. More >

R. Lamloumi^1,2, L. Hassini¹, G. L. Lecomte-Nana², M. A. Elcafsi¹, D. Smith²

CMC-Computers, Materials & Continua, Vol.43, No.3, pp. 137-152, 2014, DOI:10.3970/cmc.2014.043.137

Abstract A mathematical model was developed to simulate in 2D the spatiotemporal evolution of the moisture content, the temperature and the mechanical stress within a deformable and saturated product during convective drying. A comprehensive hydro-thermal model had been merged with a Maxwell model with two branches, assuming a viscoelastic material, a plane deformation and an isotropic hydric-shrinkage of the sample. A long sample of clay mixture with a square section was chosen as an application case. The transport and equilibrium properties of the product required for the modeling were determined from previous experiments which were independent of the drying trials. In… More >