Experimental and numerical investigations on flexural and thermal properties of nanoclay–epoxy nanocomposites

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 527; no. 29; pp. 7920 - 7926
• Main Authors: Zainuddin, S., Hosur, M.V., Zhou, Y., Narteh, Alfred T., Kumar, Ashok, Jeelani, S.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15.11.2010; Elsevier
• Subjects: Applied sciences; Composites; Damage; Dynamical systems; Exact sciences and technology; Forms of application and semi-finished materials; Mathematical models; Mechanical properties; Nanoclay; Nanocomposites; Nanomaterials; Nanostructure; Nonlinear dynamics; Physical properties; Polymer industry, paints, wood; Properties and testing; Stress-strain relationships; Technology of polymers; Thermal properties; Thermo-mechanical properties; Weibull parameters; Weibull parameters; Nanocomposites; Nanoclay; Thermo-mechanical properties; Scanning electron microscopy; Montmorillonite; Stress strain relation; Thermogravimetry; Epoxy resin; Thermomechanical properties; Dispersion reinforced material; X ray diffraction; Dynamic mechanical analysis; Composite material; Transmission electron microscopy; Non linear model; Nanocomposite; Weibull distribution; Fractography; Damaging; Bending test
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2010.08.078

▶ Effects of montmorillonite nanoclay on mechanical and thermal properties were investigated. ▶ A non-linear damage model to describe the stress–strain relationship was developed. ▶ Results showed optimum enhancement in 2 wt.% system in both thermal and mechanical properties. ▶ XRD and TEM results indicated mixed intercalation and exfoliation of nanoclay in 2 wt.% system. ▶ Good correlation was found between experimental and modeling results. The prime aim of this investigation is to study the effect of montmorillonite nanoclay on mechanical and thermal properties and to develop a non-linear damage model to describe the stress–strain relationship of epoxy resin system. Neat and nanocomposites with 1–3 wt.% clay loading were fabricated. Dynamic mechanical analysis (DMA), thermo-gravimetric analysis (TGA) and three-point bend tests were carried out to evaluate thermo-mechanical and mechanical properties. Results demonstrated optimum enhancement in 2 wt.% doped system in both thermal and mechanical properties when compared to the neat system. X-ray diffraction (XRD) and transmission electron microscopy (TEM) results indicated mixed intercalation and exfoliation of clay platelets in 2 wt.% system. Scanning electron micrographs (SEM) of 2 wt.% samples showed rougher fracture surface in comparison to neat epoxy samples. Based on the experimental results, a non-linear damage model using flexural modulus and Weibull parameters was established to describe the stress–strain relationship. These simulated strain–strain relationship coordinated well with the experimental results and show that the Weibull scale parameter, σ 0, increased whereas the Weibull shape parameter, β, remained insensitive with increasing clay content.