3. Process description

Theories on filled elastomer

92 Advanced Surface Engineering Research

Model of weak and strong linkage

Waste newsprint

Marble sludge with carbon black

fibers

Summary References

[12–14]

[15, 16]

[17–19]

[20–23]

[24–26]

[28, 29]

[32]

[34]

[35]

[36]

[4]

[37]

[38]

small particle size. Any finely divided solid material that can be dispersed in the

prevent the molecular rupture. The frictional heat occurring during the relative motion between rubber molecular chains and filler can help release the strain energy so that hysteresis can be seen in the matrix instead of breakup.

variety of inter- and intramolecular interactions. Acid/base reaction and hydrogen bonding are probably the main reactions that may occur between the rubber

The order and disorder of system correlate to the extension of the molecular

rigid fillers lead to local strains, which is greater than globally applied strains.

Strain amplification Modifications to hydrodynamic model at high strains. [19, 27, 28]

The Bueche model The fillers are connected with the molecular network chains within a filled rubber. [30, 31]

Material Short summary References

vulcanization characteristics (higher maximum torque and cure rate index, lower cure time, and scorch time), higher tensile properties, and lower tension set value.

where abrasion resistance is not significantly required. The 300% modulus values

rubber composites. The elasticity of the cofiller network structure is close to that of

in rubber formulations. The physical and mechanical properties of the rubber filled with pyrolytic tire were found to be comparable to rubber containing N772 and with

The sodium silicate and magnesium chloride treated newsprint fiber waste at 40phr can improve the electrical and mechanical properties of the rubber composite.

Marble sludge can be used as a cofiller with carbon black in natural rubber. High tensile strength, modulus, tear strength, and hardness can be achieved.

The filled rubber can be regarded to be made of strong and weak linkages. Different weak linkages can be broken by different stresses contributing to

Small particle size The reinforcement mechanism is attributed to an interfacial effect consequent upon

polymeric matrix will reinforce rubber compounds.

Slippage at interface Stress can be redistributed by the slippage of molecular chains, and then helps

Chemical reaction Functional groups on the surface of carbon black are most likely subjected to a

Stored energy function Use thermodynamic concepts to study the relationship between stress and strain.

Hydrodynamic theory Rigid fillers typically increase the stiffness of the elastomer. The presence of the

Chicken eggshell The eggshell calcium carbonate filled epoxidized natural rubber showed superior

Fly ash Fly ash (up to 60 phr) can be used as a nonreinforcing filler for ESBR compounds,

Soy spent flakes The soy spent flakes can partially replace carbon black as the reinforcement cofiller in

Lignin Reinforcing properties of lignin as filler in nitrile rubber can be improved on suitable

Pyrolytic tire Chars obtained from pyrolytic tire can be successfully reused as semireinforcing fillers

remained unchanged with increasing loading.

chemical treatment for good thermal stability.

matrix and the carbon black.

Table 1. Eight postulations of carbon black reinforcement mechanisms [11].

carbon black-filled composites.

N772 and silica.

Table 2. Novel rubber filler from green feedstock [11].

chains.

softening.

## 3.1. Feedstock and reference material

#### 3.1.1. Feedstock: coconut shell

As a single and simple genus species, coconut is grown around the world sharing similar properties. In order to make the experiments standardized, after being crushed into to small pieces (less than 10 mm) by a laboratory-scale hammer miller (Glen Creston, UK), the small pieces of coconut shell were then dried at 105C to constant weight, to reduce the moisture content (Figure 2).

## 3.1.2. Reference material: carbon black N772

Carbon black N772 belongs to low to semidispersion, middle-active grades of carbon black, which has the largest particle size and lowest structural and surface area among the whole

Figure 2. Dried coconut shell [11].

range of carbon black. N772 provides high elasticity, low heat-up, good aging-resistance, and superior dynamic performance to the technical rubber products or tire frames.

particles in the micron and submicron (or nanometer) particle size. Moreover, it has been found that wet milling can cost-effectively create uniformly fine particles with limited or no contamination [45]. The optimum condition for wet TEMA milling was confirmed as 1:1 liquid and solid ratio, 1.5 min grinding time. After the milling process, the wet samples were

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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Surface area of the samples were characterized by liquid nitrogen (at 77 K) adsorption and desorption method using the OMNISORP 100. The BET surface area can be calculated with the isotherms by using the Brunauer-Emmett-Teller equation [46]. The t-plot method was used to find the micropore volume and the combined macropore and mesopore surface area [47]. The significant surface areas were concluded from the difference between the BET surface area and the macropore and mesopore surface area and used to establish the relationship between pore

Toluene extraction of the char filler was test according to the ASTM D 1618-99 (Standard Test Method for Carbon Black Extractables—Transmittance of Toluene Extract) [48]. This method covers the measurement of the degree of toluene discoloration by carbon black extractables

Test Method A—Boiling Slurry of ASTM D1512-05 Standard Test Method for Carbon Black—pH value [49] was applied to obtain the pH value of the char filler. The pH value is very essential

The oxygen surface groups on char filler were investigated by the Boehm titration [17]. This method is based on the principle that oxygen groups on surfaces have different acidities and can be neutralized by bases of different strengths. Sodium hydroxide (NaOH) is the strongest base generally used, and is assumed to neutralize all Brønsted acids, while sodium carbonate (Na2CO3) neutralizes carboxylic and lactonic groups and sodium bicarbonate (NaHCO3) neutralizes carboxylic acids. The difference between the uptake of the bases can be used to

Styrene-butadiene rubber (SBR) is widely applied in tire treads. When protected by additives, excellent traction properties, good abrasion resistance, and good aging stability can be achieved [51]. It is reported that the most common use of SBR is in pneumatic tires with around 50% of car tires being made from a range of types of SBR. A widely used generic SBR

and is useful in controlling the reaction process for the production of carbon black.

dried at 105C for 24 h until constant weight.

size distribution and rubber uptake capacity of the fillers.

since it can affect the vulcanization of some rubber compounds.

quantify the oxygen surface groups on a char sample [50].

3.4. Char filler characterization

3.4.1. Textural characterization

3.4.2. Toluene extraction

3.4.3. pH value

3.4.4. Boehm titration

3.4.5. In-rubber testing
