Filler reinforcement in natural rubber

Theory and Mechanisms of Filler Reinforcement in Natural Rubber... 

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. 

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. 

The extent of reinforcement produced by the carbon black is affected by factors such as (i) particle size, (ii) structure, (iii) physical nature of the surface and (iv) degree of filler dispersion in the rubber matrix. 

Non- or semi-reinforcing fillers These are usually added to reduce cost. In natural rubber or polychloroprene, they may be used alone, but with non-crystallizing polymers such as butadiene - acrylonitrile or styrene - butadiene copolymers, they can only be used in conjunction with a reinforcing filler. Their effect is to reduce tensile strength and elongation, tear resistance and resistance to set. The effect on modulus varies according to choice of filler, but it is always much weaker than that of a reinforcing filler. 

A common practice to enhance the properties of rubber products is by loading large amounts of fillers that are either reinforcing or non-reinforcing. Traditionally carbon black, precipitated silica and calcium carbonate are used to reinforce the natural rubber matrix in bulk amounts, up to 80 phr in some cases. Addition of large quantities of fillers reduces the elasticity and processability and increases the weight of the natural rubber composites. 

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