1. Introduction

At present, it is seldom to see a rubber product using the polymer in an unfilled condition. Various materials are added during the rubber manufacture process. Carbon black is widely used as a rubber reinforcing filler from the third century B.C. in China. It is added to help to enhance the physical properties of the given rubber, such as hardness, tensile strength, and tear strength, etc. In 2015, the global production of carbon was about 13.9 million metric tons. It is indicated that by 2022, the production will reach 19.2 million metric tons [1]. There is no doubt that the cost of making carbon black will increase rapidly. As a result, the potential effect of the prediction may lead to an increasing demand of the fossil fuel hydrocarbon feedstock. On the other hand, the manufacture of carbon black is not only energy-intensive but also

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and eproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

unsustainable in the long term as a feedstock due to the finite supply and the contribution to global warming.

between the rubber and the filler surface. It is necessary to note that meso- and macropores seem to play the decisive role on the surface unlike micropores for the application of activated carbon. Since the rubber polymer chains are much larger than the micropores, the polymer

The Potential of Pyrolytic Biomass as a Sustainable Biofiller for Styrene-Butadiene Rubber

http://dx.doi.org/10.5772/intechopen.79994

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The research of the reinforcement mechanism offered by carbon black has been widely undertaken since 1960s [10]. It is widely known that the vulcanization process can only achieve resilient properties with little strength. Then, the strength properties need to be introduced by the addition of "reinforcement" fillers. After carbon blacks are added to the rubber compound, several changes occur: (1) an increase in modulus, or stress at a particular strain, (2) an increase in elongation at break for vulcanizates having a given degree of cross-linking, and (3) consequently, an increase in tensile strength [10, 11]. The improvement of stiffness and the physical properties such as tear resistance, tensile strength, and abrasion resistance are regarded as the crucial contribution of carbon black. The reinforcing ability of a filler can be demonstrated in Figure 1; the only difference between two SBR vulcanizates is the presence or absence of 50phr carbon black N220 in the recipe. With the addition of carbon black N220, the stress-strain curve

Large amount of literatures report about the reinforcement properties of carbon black for decades. So far, there are more than eight postulations have been wieldy applied to explain

Due to the increasing price of natural rubber and other compounding ingredients, there are several concerns about the ongoing use of nonrenewable resources based carbon black feedstock.

Figure 1. Comparison between filled and unfilled rubber matrix [11, 12]. (Rubber: SBR 1502, 100; zinc oxide, 3; stearic acid, 1.5; Santoflex 13, 0.5; Santoflex 77, 0.5; Sundex 8125, 3; DPG, 0.3; Santousure NS, 1.2; Sulfur, 2. Press cure: 40 min at

shows a sharp rise, almost 10-fold compared with the unfilled rubber.

the reinforcement mechanisms, which are given in Table 1.

153C. Same formulation with addition of 50 phr N220 carbon black).

cannot access these pores.

Given the increasing pressure against using nonrenewable resources, it is essential to develop alternative materials to act as novel rubber fillers. Recently, several researches have been conducted focusing "green" fillers, which are based on the waste materials having potential "renewability" [2]. By using bio-based fillers, the dependence on fossil fuel would be improved and a sustainable material basis for rubber filler production could be established. In this chapter, the development of new type of fillers for rubber materials based on char produced during pyrolysis of biomass (coconut shell) is illustrated.
