Preparation and properties of styrene–butadiene rubber based nanocomposites: The influence of the structural and processing parameters

Abstract

Rubber-based nanocomposites were prepared with octadecyl amine modified sodium montmorillonite clay and styrene-butadiene rubber with different styrene contents (15, 23, and 40%). The solvent used to prepare the nanocomposites, the cure conditions, and the cure system were also varied to determine their effect on the properties of the nanocomposites. All the composites were characterized with X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and transmission electron microscopy (TEM). The XRD studies revealed exfoliation for the modified clay-rubber composites. The TEM photomicrographs showed a uniform distribution of the modified clay in the rubber matrix. The thickness of the particles in the exfoliated composites was around 10 -15 nm. Although the FTIR study of the unmodified and modified clays showed extra peaks due to the intercalation of the amine chains into the gallery, the spectra for the rubber-clay nanocomposites were almost the same because of the presence of a very small amount of clay in the rubber matrix. All the modified clayrubber nanocomposites displayed improved mechanical strength. The styrene content of the rubber had a pronounced effect on the properties of the nanocomposites. With increasing styrene content, the improvement in the properties was greater. Dicumyl peroxide and sulfur cure systems displayed similar strength, but higher elongation and slightly lower modulus values were obtained with the sulfur cure system. The curing of the samples at four different durations at 160°C showed that the cure time affected the properties.

Evaluating the effect of processing conditions and organoclay content on the properties of styrene-butadiene rubber/organoclay nanocomposites by response surface methodology

“…As discussed later the mechanical properties are affected by these morphologies. Similar XRD patterns have been reported for exfoliated and intercalated SBR/organoclay composites in literatures [20][21][22]. By TEM, one can obtain information on the real state of spatial distribution of the nano particles.…”

Preparation and characterization of elastomer‐based nanocomposite gels using an unique latex blending technique

“…This is believed to be due to wall slippage of polymer chains against the clay and change of steric hindrance of bulky styrene groups. 27,28 The effect of Na þ -MMT on the storage modulus (E 0 ) values of the nanocomposite gels is also compared in Figure 7(a,b) [as insets]. The moduli of the nanocomposite gels are much higher than those of the unfilled control NS and SBS gels, which further reflect the strong confinement of nano-dispersed silicate layers on the rubber chains.…”

“…Sadhu and Bhowmick have reported similar observations from SBR and montmorillonite clay based nanocomposites prepared by solution mixing route. 28 The impressive level of improvement in the Young's moduli and the tensile strength of the nanocomposites can be ascribed to the dispersed structure of clay at the nano level, the high aspect ratio, and the much improved polymer-filler interaction. The exfoliated morphology of the nanocomposite gels as evident from TEM and XRD is primarily responsible for the large enhancement in the mechanical properties.…”

Preparation and characterization of nanocomposites based on thermoplastic elastomers from rubber–plastic blends

“…The polymers that have been extensively studied are nylon, [1][2][3][4][5][6][7][8][9][10][11] polypropylene, [12][13][14][15][16] polyurethane, 17 natural rubber (NR), 18 epoxidized natural rubber (ENR), 18 ethylene-vinyl acetate copolymer (EVA), 19 styrene-butadiene rubber (SBR), 20,21 butadiene rubber (BR), 22 acrylonitrile-butadiene rubber (NBR), 22 etc. Among the thermoplastic elastomers (TPE)/clay nanocomposites (TPN), EVA containing 28% vinyl acetate (EVA-28) 23 and SBS 24 with organomodified montmorillonite have been reported so far.…”