Role of calcium stearate as a dispersion promoter for new generation carbon black‐organoclay based rubber nanocomposites for tyre application

Abstract

A novel carbon black (CB) and nanoclay (NC) dual phase‐filled system in SBR matrix has been developed to be employed as a tyre tread compound with optimized performance properties. The nanocomposite has shown improved dynamic properties i.e. rolling resistance (tan δ at 60°C) and wet skid resistance (tan δ at 0°C), for relatively lower loading of NC (3 phr). However, the mechanical properties and wear resistance combined with above mentioned dynamic properties have been further improved by direct substitution of stearic acid with calcium stearate. This has been argued to be due to enhanced filler‐rubber interaction by the strong ionic interactions between the calcium ion (Ca++) and layered silicates (NC) having anionic surface. Transmission electron microscopy and low angle X‐ray diffraction studies have revealed the role of calcium stearate as a dispersion promoter for organoclay. Fourier transform infra‐red spectroscopy study has shown a shift in the SiOSi bond towards lower wave number indicating better polymer‐clay interaction. A detailed investigation on the dynamic rheological behavior of SBR‐CB‐NC nanocomposites has been carried out using rubber process analyzer to invoke an insight into the processing behavior of these composites. POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers

Giving a Second Opportunity to Tire Waste: An Alternative Path for the Development of Sustainable Self-Healing Styrene–Butadiene Rubber Compounds Overcoming the Magic Triangle of Tires

“…As seen in Figure 2, the SBR/10GTR compound has the overall best performance, since the wet grip and rolling resistance are their maximum and minimum, respectively. These results suggest that small amounts of GTR (10 phr) are well dispersed in the SBR matrix enhancing the rubber-filler interactions [34]. Similar results were found by Kim et al [35].…”

“…Hence, the presence of NR (which is a very low hysteresis rubber) in the GTR composition could also be a key factor improving the performance in terms of rolling resistance [36]. Nonetheless, at higher GTR loading (20 and 30 phr), the formation of agglomerated structures seems to dominate versus the increased amount of NR, leading to higher values of tan δ at 60 • C, and hence a higher rolling resistance [34]. Other authors have also found that the filler dispersion is the dominant factor governing the rolling resistance of vulcanizates [37].…”

“…At low temperatures, a higher energy dissipation due to the increased rubber chains slippage and to the disruption of the filler network results in high values of tan δ [37]. While at 60 • C, the loss of conformational entropy with the cyclic deformation, the disentanglement of network chains, and the destruction of the filler network are reflected in a higher value of tan δ [34]. After the healing protocol is applied, tan δ at both temperatures lowers down, achieving an almost complete recovery of the initial value.…”

Steel Cord Skim Compound for Radial Tyre Based on Natural Rubber-Carbon Black-Organoclay Nanocomposites

“…Since some of the polymer molecules remain intercalated within the clay galleries, it may allow the slippage of rubber molecules leading to an increase in the EB (%) values of the nanocomposites compared to control compound A, which is consistent with our earlier published literatures [17][18]. The compounds B & C show an optimum balance between physical properties.…”

Dynamic properties of star‐shaped, solution‐polymerized styrene–butadiene rubber and its cocoagulated rubber‐filled with silica/carbon black

“…Thus, silica has played a more and more important role in preparing green tire tread materials . With excellent reinforcement and abrasion resistance, carbon black (CB) is also one kind of indispensable filler for the preparation of tire tread materials . Furthermore, star‐shaped solution‐polymerized styrene–butadiene rubber (SSBR) with end groups coupled by SnCl 4 has many characteristics, including a low internal friction loss, few free macromolecular terminals, and good wet traction.…”