Influence of Silica and its Different Surface Treatments on the Vulcanization Process of Silica Filled SBR

Abstract

The effect of different silica treatments on the vulcanization of silica filled Styrene Butadiene Rubber (SBR) is investigated. The concentration, the length and the functionality (coupling or non coupling) of the silane used for this treatment are the parameters studied. It is shown that the silane grafting, by covering the silica surface, modifies the adsorption and desorption on this surface of the accelerators used in the vulcanization system, which in turn modifies the crosslinking kinetic and therefore should influence the final crosslinking state of the matrix.

Some Remarks on the Effect of Interphases on the Mechanical Response and Stability of Fiber-Reinforced Elastomers

“…When compared with the classical results (55)-(56), it should be apparent from expressions (50) and (51) that the presence of interphases in fiber-reinforced materials can have a drastic effect on the values of the critical loads at which macroscopic instabilities develop, even for very small volume fraction c (3) 0 of interphases. This is more explicitly revealed by the case of rigid fibers, when is easily deduced from relations (54) and (57) that for materials with interphases that are softer than the matrix -in the sense that µ (3) < µ (1) and irrespectively of the compressibility function h(J) -the onset of macroscopic instabilities can occur at much smaller compressive stresses than for the corresponding materials without interphases. The opposite is true for the case when the interphases are stiffer than the matrix (i.e., µ (3) > µ (1) ).…”

“…The critical expressions (50) and (51) apply to general heterogeneity contrast µ (2) /µ (1) between the matrix and the fibers. In practice, however, actual fibers in reinforced elastomers are usually several orders of magnitude stiffer than the matrix phase.…”

“…We note in particular that the dependence on J, which measures the overall compressibility of the fiber-reinforced solid, is highly non-trivial (and not simply additive). The material constants µ (1) , µ (2) and volume fractions c…”

“…In the case when the surfaces of the fillers are suitably treated to form strong bonds with the matrix, such interphases can be up to one order of magnitude stiffer than the matrix material in the small-deformation regime (see, e.g., [1,2] and references therein), and possibly even more at large deformations [3]. On the other hand, for untreated surfaces or surfaces that are treated unfavorably to form bonds with the matrix, the interphases can be significantly softer [4].…”

The Effect of Surface Area of Silicas on Their Reinforcing Performance to Styrene-butadiene Rubber Compounds

“…4,5 Precipitated silica gradually replaces carbon black because the silica reinforcing system accompanied by suitable coupling reagents can achieve significant improvements of both rolling resistance and wet traction. The amount of silica added to the SBR compounds has gradually increased to around 100 phr.…”