Nanocomposites rubber matrix

During the past decade, rubber-layered silicate nanocomposites have been extensively studied for a variety of applications and in this review the preparation and characterization of such layered silicate-rubber composites is discussed. However, use of another type of clay, called anionic clay or LDH, in the rubber matrix is rather uncommon. In this section, rubber-LDH nanocomposites are described, including the synthesis and characterization of OLDH, preparation of rubber-LDH nanocomposites, and their special properties [94, 95]. 

Furthermore, another advantage of nanofillers is not only to reinforce the rubber matrix but also to impart a number of other properties such as barrier properties, flammability resistance, electrical/electronic and membrane properties, and polymer blend compatibility. In spite of tremendous research activities in the field of polymer nanocomposites during the last two decades, elastomeric nanocomposites... 

This book focuses on the synthesis and characterization of natural rubber composites and nanocomposites, the interaction between reinforcing agents and the rubber matrix and their effect on different properties. The reinforcing effect of traditional fillers in micro range and the effectiveness of these nanofillers are discussed. This book on natural rubber and nano composites comprises of the most recent research activities that will, unquestionably, be a vital reference book for scientists in both the academic and industrial sectors, as well as for individuals who are interested in natural rubber materials. 

Table 2.1 presents a summary of the information available in the scientific literature for C and OC dispersion in isoprene rubbers. The state of dispersion depends on the clay type, pristine or organically modified, and on the blending technology adopted. Table 2.2 shows that nanocomposites are formed with a pristine clay only through emulsion blending. In fact, the inorganic nature of clay layers hinders their compatibility with the rubber matrix. 

Barrier properties of a rubber matrix are remarkably improved thanks to clay addition. The tortuous path model is proposed to explain this phenomenon. In a NR/Mt nanocomposite prepared from emulsion blending, 1, 2 and 3 phr of clay led to more than 35% and to about 45% and 50% reduction of oxygen permeability, respectively. " 3 phr of OC (Mt/ didodecyl methyl amine) gave a 50% reduction of the oxygen permeability and a 40% reduction of toluene absorption at 20 °C. About 10% and 15% reduction of oxygen permeability were obtained with 5 and 10 phr of OC, respectively, and 30% reduction of toluene absorption was achieved with 15% OC, at 30 °C. ... 

The CNT/NR nanocomposites were fabricated through solvent mixing assisted with a two-roll mill. Compared to the neat NR and traditional CB/NR composite, the over-curing reversion of CNT/NR nanocomposite abated. The dispersion of the treated CNTs in the rubber matrix and interfacial bonding between them were satisfactory. 

The effectiveness of organoclay in NR was observed and reported by Carli et They evaluated the technical feasibility of NR nanocomposites with Cloisite 15A, a commercial organoclay to substitute conventional silica (Si02) filler. TEM analysis indicated that the OMt was homogeneously dispersed in the rubber matrix. A shift of the characteristic peaks to lower angles was observed in XRD, attributed to the intercalation of the OMt by macromolecular rubber chains. Based on the mechanical properties of the compounds they concluded that 50 phr of silica can be replaced by 4 phr of OMt with a reduction in the filler content by 12.5 times, without adversely affecting the tensile properties of the final material even after ageing. 

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