Clay reinforcement recent developments

This is Volume 2 of Natural Rubber Materials and it covers natural rubber-based composites and nanocomposites in 27 chapters. It focuses on the different types of fillers, the filler matrix reinforcement mechanisms, manufacturing techniques, and applications of natural rubber-based composites and nanocomposites. The first 4 chapters deal with the present state of art and manufacturing methods of natural rubber materials. Two of these chapters explain the theory of reinforcement and the various reinforcing nanofillers in natural rubber. Chapters 5 to 19 detail the natural rubber composites and nanocomposites with various fillers sueh as siliea, glass fibre, metal oxides, carbon black, clay, POSS and natural fibres ete. Chapters 20-26 discuss the major characterisation techniques and the final ehapter covers the applications of natural rubber composites and nanoeomposites. By covering recent developments as well as the future uses of rubber, this volume will be a standard reference for scientists and researchers in the field of polymer chemistry for many years to come. 

Polymer matrix nanocomposite is the most important type of nanocomposite in which the performance of a polymer matrix can be enhanced by appropriately adding nanoparticulates to it [12] and good dispersion of the filler can be achieved [ 12]. A imiform dispersion of nanoparticles leads to a very large matrix/filler interfacial area, which changes the molecular mobility, the relaxation behavior and the consequent thermal and mechanical properties of the material. A polymer matrix could be reinforced by much stiffer nanoparticles [13,14] of ceramics, clays, or carbon nanotubes, etc. Recent research on thin films (thickness < 50 micrometer) made of polymer nanocomposites has resulted in a new and scalable synthesis technique increasing the facile incorporation of greater nanomaterial quantities [15]. Such advances will enable the future development of multifunctional small scale devices (i.e., sensors, actuators, medical equipment), which rely on polymer nanocomposites. 

Polymer-based nanocomposites have been widely developed over the last two decades due to their highly specific mechanical properties compared to conventional polymer-based microcomposites [1], The reinforcement mechanism in nanocomposites may be attributed to the strong inter-particle and particle-matrix interactions due to the large specific surface area. Among this recent class of materials, the most intensive researches are focused on polymer-based nanocomposites reinforced with inorganic montmorillonite clay, and especially on their synthesis and characterization. However, their micromechanical modeling has been less investigated so far. 

A micromechanics-based model recently proposed by Anoukou et al. [7,8] was adopted in the present investigation to develop a pertinent model for describing the viscoelastic response of polyamide-6-based nanocomposite systems. Comparisons between the results from the micromechanical model and experimental data were considered for nanocomposites reinforced with modified and unmodified montmorillonite clay. Reasonable agreement between theoretical predictions and experimental data was noticed, the discrepancies being attributed to both uncertainties in the input data and a possible effect of reduced chain segment mobility in the vicinity of clay nanoplatelets. 

Recently, the utility of inorganic nanoparticles as additives to enhance the polymer performance has been established. Various nano reinforcements currently being developed are nano-clay (layered silicates),cellulose nanowhiskers, ultra fine layered titanate, and carbon nanotubes. Carbon nanotubes, however, are the most promising of the new nanomaterials. Carbon nanotube-based polymer composites are poised to exhibit exceptional mechanical, thermal and electrical properties. ... 

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