Synthesis and properties of epoxy-phenolic clay nanocomposites

Abstract

Abstract. An epoxy-phenolic resin suitable for use as a composite matrix was reinforced with modified nanoclay (montmorillonite type). Characterization by x-ray diffraction and transmission electron microscopy (TEM) demonstrated that intercalated nanocomposites were formed with an inter-gallery distance of approximately 10 nm. The influence of nanoparticles on tensile strength and modulus, fracture toughness, and impact toughness was measured and compared with the unreinforced polymer. The results revealed that the maximum enhancement in stiffness and toughness was achieved with 2.5 wt% filler content. The enhancement in toughness behavior was attributed to the activation of multiple energy-dissipating damage mechanisms in the nanocomposites.

Investigation of correlation between dielectric parameters and nanostructures in aqueous solution grown poly(vinyl alcohol)-montmorillonite clay nanocomposites by dielectric relaxation spectroscopy

“…Synthesis and structural characterization of polymer-clay (organic-inorganic) nanocomposites (PCNs) are of technological interest due to significant improvement in the useful properties of composite materials over those of the pure polymer [1][2][3][4][5][6][7][8][9][10][11][12]. For the preparation of poly(vinyl alcohol) (PVA)-layered silicate nanocomposite, montmorillonite (MMT) clay is the most commonly used, which has hydrophilic property, and 2:1 phyllosilicate laminar structure.…”

Low frequency dielectric relaxation processes and ionic conductivity of montmorillonite clay nanoparticles colloidal suspension in poly(vinyl pyrrolidone)−ethylene glycol blends

“…The investigation of broadband dielectric spectroscopy (BDS) of the materials covers nowadays the extraordinary spectral range from 10 -6 to 10 12 Hz [19]. The BDS frequency ranges from 10 -1 to 10 -3 Hz and 10 -4 to 10 -6 Hz are denoted by very low and ultra low (quasi-dc) spectrums respectively, whereas ~10 0 -10 4 Hz, ~10 5 -10 7 Hz and 10 8 -10 12 Hz are known as low frequency, middle frequency and high frequency spectrums, respectively. The BDS characterization of the dielectric materials provide the confirmative information on the intra-and intermolecular dynamics, the degree of intermolecular H-bond interactions, cooperativity between guest and host molecules, and ionic and electrode polarization processes related to the molecular structures [19,20].…”

“…Swelling of the clay is mainly due to solvent intercalation (absorption) in the clay galleries, and also because of the adsorption of solvent molecules on the hydroxylated aluminate clay surfaces through H-bond interactions, which results the clay exfoliation. The intercalated and exfoliated clay sheets in polymeric solvent results the organic-inorganic nanocomposites of highly complicated structures, which is responsible for the improved thermal, mechanical, gas barrier and electrical properties of the polymer-clay nanocomposites (PCNs) [6][7][8][9][10][11][12][13][14][15][16][17][18]. The investigation of broadband dielectric spectroscopy (BDS) of the materials covers nowadays the extraordinary spectral range from 10 -6 to 10 12 Hz [19].…”

“…The intercalated and exfoliated clay sheets in polymeric solvent results the organic-inorganic nanocomposites of highly complicated structures, which is responsible for the improved thermal, mechanical, gas barrier and electrical properties of the polymer-clay nanocomposites (PCNs) [6][7][8][9][10][11][12][13][14][15][16][17][18]. The investigation of broadband dielectric spectroscopy (BDS) of the materials covers nowadays the extraordinary spectral range from 10 -6 to 10 12 Hz [19]. The BDS frequency ranges from 10 -1 to 10 -3 Hz and 10 -4 to 10 -6 Hz are denoted by very low and ultra low (quasi-dc) spectrums respectively, whereas ~10 0 -10 4 Hz, ~10 5 -10 7 Hz and 10 8 -10 12 Hz are known as low frequency, middle frequency and high frequency spectrums, respectively.…”

Effect of nanofillers on the properties of a state of the art epoxy gelcoat

“…While the layered exfoliated structure and the platelet shape of the nanographite is responsible for the enhanced tensile properties [31][32][33][34]. The reinforcing mechanisms of ceramic fillers like the titanium dioxide and the montmorillonite clay that were used in the present study have been attributed to their large surface area and surface reactivity of the inorganic phase, the corresponding restricted mobility of the polymer chains and to the increase in the effective particle volume fraction in the nanocomposite [35][36][37]. The fracture properties of the gelcoats can be seen in Figure 3.…”