Clay reinforcement natural rubber

In some polymer nanocomposites the initial thermal decomposition will be accelerated due to the presence of alkyl ammonium surfactant on the surface of the clay. For instance in PVC the quaternary ammonium salts may accelerate the degradation of PVC.However, this problem does not exist in clay reinforced natural rubber nanocomposites. 

Rubber nanocomposites can be based on many rubber matrices, for example (clay reinforcement) natural rubber [41] or synthetic mbber materials such as styrene-butadiene rubber [42], nitrile-rubber [43], EPDM [44] or polyurethane [45, 46],... 

It is a pity that because whiting, clay and other such fillers are known not to reinforce natural rubber, they have not been studied in the same way and to the same depth as carbon black. Nevertheless, it is within the experience of most rubber compounders that as the reinforcing effect increases (it may be better said that as... 

The effect of polymer-filler interaction on solvent swelling and dynamic mechanical properties of the sol-gel-derived acrylic rubber (ACM)/silica, epoxi-dized natural rubber (ENR)/silica, and polyvinyl alcohol (PVA)/silica hybrid nanocomposites was described by Bandyopadhyay et al. [27]. Theoretical delineation of the reinforcing mechanism of polymer-layered silicate nanocomposites has been attempted by some authors while studying the micromechanics of the intercalated or exfoliated PNCs [28-31]. Wu et al. [32] verified the modulus reinforcement of rubber/clay nanocomposites using composite theories based on Guth, Halpin-Tsai, and the modified Halpin-Tsai equations. On introduction of a modulus reduction factor (MRF) for the platelet-like fillers, the predicted moduli were found to be closer to the experimental measurements. 

The proven compounding practice for the natural rubber layer is to load it with 30 phr of graphite, 30 phr of semi-reinforcing carbon black filler and 50 phr of inert filler, china clay. A low sulfur curing system is adopted for heat resistance with a suitable antioxidant to prevent flex-cracking. A typical chlorine resistant soft natural rubber compound formula is given in Table 3.2. 

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. 

Elastomers such as natural rubber (NR) are of great importance in manufacturing industries. However, they possess properties which are less than that required for practical applications. This has led to the use of fillers for reinforcement of their properties. For practical applications, the physical and mechanical properties of elastomers are reinforced with mineral fillers such as silica, CB, clay fibre, short fibre and layered silicate. ... 

Clay Reinforcement in Natural Rubber on Micro and Nano Length Scales... 

Volume 1 of this book is comprised of 25 chapters, and discusses the different types of natural rubber based blends and IPNs. The first seven chapters discuss the general aspects of natural rubber blends like their miscibility, manufacturing methods, production and morphology development. The next ten chapters describe exclusively the properties of natural rubber blends with different polymers like thermoplastic, acrylic plastic, block or graft copolymers, etc. Chapter 18 deals entirely with clay reinforcement in natural rubber blends. Chapters 19 to 23 explain the major techniques used for characterizing various natural rubber based blends. The final two chapters give a brief explanation of life cycle analysis and the application of natural rubber based blends and IPNs. 

Clay reinforcement has already been used in various polymer systems including polyamide, polypropylene, polystyrene and polycarbonate. However, the major challenges in using clay reinforcement in natural rubber are its nonpolar nature, the conventional processing methods used, such as a two-roll mill, and the high molecular weight of natural rubber polymeric chains. 

An alternative method of producing natural rubber based clay reinforced nanocomposites with outstanding properties is by using a spray drying technique. In this technique the siUcate layers of clay will be well dispersed in an irradiated polymer latex and this mixture will be sprayed through hot air to produce micrometre-sized liquid droplets. When the solvent is fully evaporated, micrometre-sized polymer spheres with delaminated clay silicate layers on their surface are produced. These spheres can later be melt blended with natural rubber to produce ternary nanocomposites. It is noteworthy that exfoliation of nanofillers can still be achieved without modification of the nanofiller surface, thus the expensive modification process can be eliminated. 

Clay Reinforcement in Natural Rubber Based Blends EVA Natural lubbeirOisaiiochy... 

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