Role of Material Composition in the Construction of Viscoelastic Master Curves: Silica-Filler Network Effects

Abstract

One of the important aspects in the development of new tire compounds is the correlation between the dynamic mechanical properties of the rubber, measured on a laboratory scale, and the actual tire performance. The measuring protocol for dynamic mechanical properties with high precision and good correlation with tire properties is therefore of main concern. To predict wet traction, the viscoelastic behavior of the rubber materials at high frequencies (in the MHz range) need to be known. Viscoelastic master curves derived from time-temperature superposition can be used to describe the properties of the materials over a wide frequency range. The construction of master curves for tread compounds filled with different amounts of silica is discussed. From the vertical shifts as a function of temperature, activation energies are derived that apparently are in the linear response region by fulfilling the Kramers-Kronig relations, and their values correspond to physical phenomena as the underlying principle. Strain sweep viscoelastic measurements, per definition outside the linear region, lead to much higher activation energies. Because the deformation strains employed for these strain sweep measurements are more realistic for wet traction or skidding phenomena, it is concluded that the value of the above measurements in the linear region to predict traction is only limited or a first but still important indication.

Understanding the Influence of Oligomeric Resins on Traction and Rolling Resistance of Silica-Reinforced Tire Treads

“…As reduced filler-filler interaction and increased filler-polymer interaction is the essence of less hysteresis and consequently lower RR of tire treads, these reduced Payne effects suggest improvements in the RR region. 20 To judge the influence of these resins on RR in detail, the results of tan d plotted against temperature are presented in Figure 4 for a RR temperature range of 30 8C to 80 8C. With the exception of sample C-6, which shows erratic behavior, and apart from the scatter in the curves resulting from the rounding of the tan d values to three decimal places, all compounds containing resins B and C clearly show a reduction in tan d relative to the reference, particularly at 60 8C.…”

Highly epoxidized soybean oil in replacement of mineral oil for high performance on silica-filled tread rubber compounds

“…It is widely accepted that better wet grip performance of tires is related to higher tan δ values at 0°C 30 where the energy dissipation is mainly associated with polymer chains movement. 31 Analyzing the data from Table 3, it is observed that the tan δ value at 0°C is increased with the oil content because of the viscous contribution from ESO, promoting the movement of some segments of SBR chains with energy absortion. 9,23…”

“…According with this predictor, the major contribution of the dissipation energy is attributed to the breakdown and reformation of the filler network. 31…”

An ultrasound method for characterization of viscoelastic properties in frequency domain at small deformations

“…where the fitting constant (Table 2) have been identified by means of DMA frequency sweep tests at different temperatures on the same slab compounds. 47 Thus, the temperature shifting from the starting value corresponding to 0.2 MHz to equivalent ones at the frequency of interest is performed. Once shifted the data as displayed in Figure 10(b), the authors have analyzed the viscoelastic loss factor determined by means of ultrasounds measurements together with the reference master curves.…”