Study of morphological and mechanical performance of amine‐cured glassy epoxy–clay nanocomposites

Abstract

The effect of three different alkylammonium-modified montmorillonite on morphological and mechanical properties of glassy epoxy-amine nanocomposites is reported. Small amounts of clays <10 phr (part per hundred of resin) were used in each system of nanocomposite. The morphology of the prepared nanocomposites was performed by means of X-ray diffraction and transmission electron microscopy. Differential scanning calorimetry (DSC) was used to investigate the glass transition temperatures (T g ). Mechanical properties were based on tensile characteristics (Young's modulus), impact strength, and fracture toughness. The measured moduli were com-pared to theoretical predictions. Scanning electron microscopy was used to study the morphological structure of the fracture surfaces of impacted specimens. It was found that at a low content of 2 phr (1.2 wt %) of nanoclays, the impact strength and the fracture toughness were improved by 77 and 90% respectively, comparatively to the neat epoxy, whereas DSC revealed a reduction of the T g of nanocomposites.

Multifunctional Cu2+‐montmorillonite/epoxy resin nanocomposites with antibacterial activity

“…65,66 TEM analyses showed some exfoliated and intercalated structures in both nanocomposites containing 1% wt and 3% wt of platelets dispersed inside the epoxy matrix in agreement with the X-ray diffraction data. A homogeneous distribution of the clay in the case of epoxy resin nanocomposites with 1% wt and 3% wt of clay content with rare agglomeration of the particles, which were distributed along the brittle fracture surface together with some micrometric clustered structure with agglomerates up to a size of few microns, were also observed.…”

“…[Color figure can be viewed at wileyonlinelibrary.com] ESEM micrographs at 3003 in Dual BSD of the glass fiber reinforced laminates after tensile failure: (A) 1% wt Cu 21 -MMT; (B) 3% wt Cu 21 -MMT.ARTICLEWILEYONLINELIBRARY.COM/APP fracture toughness, elastic modulus and impact strength upon increasing of clay content in epoxy nanocomposites were previously observed66 and were related to the different effect of intercalated and exfoliated platelets on the energy-absorbing behavior of the nanocomposite. [Color figure can be viewed at wileyonlinelibrary.com] Effect of the nanomodification of the epoxy resin on the fracture toughness.…”

A Novel Method for Manufacturing High‐Performance Layered Silicate/Epoxy Nanocomposites Using an Epoxy–Diamine Adduct to Enhance Compatibility and Interfacial Reactivity

“…The T g of T1, which was incorporated with TMA–MMT and displayed the best morphology from §3.2, experienced the most decrease. This phenomenon is consistent with the results reported in literature, highly cross‐linked resin systems with high glass transition temperature led to a steady decrease in T g with the incorporation of organic MMT …”

Analyzing the influence of particle size and stiffness state of the nanofiller on the mechanical properties of epoxy/clay nanocomposites using a novel shear-stiff nano-mica

“…As described by Messersmith and Giannelis [25], the observed changes in the glass transition temperature are related to the molecular mobility of polymer chain segments at the polymer/nanofiller interface. Consequently, the changes are strongly dependent on both the quality of the interfacial interaction and specific surface area [5,26,27]. In the present study, the aliphatic dodecyl tail of the surface modifier is too short to achieve any entanglements, and it is not capable to form covalent cross-links with the thermosetting matrix during curing.…”