Fourier-Transform Rheology of Unvulcanized, Carbon Black Filled Styrene Butadiene Rubber

Abstract

Rubber materials filled with reinforcing fillers display nonlinear rheological behavior at small strain amplitudes below γ0 < 0.1. Nevertheless, rheological data are analyzed mostly in terms of linear parameters, such as shear moduli (G′, G″), which loose their physical meaning in the nonlinear regime. In this work styrene butadiene rubber filled with carbon black (CB) under large amplitude oscillatory shear (LAOS) is analyzed in terms of the nonlinear parameter I3/1. Three different CB grades are used and the filler load is varied between 0 and 70 phr. It is found that I3/1(φ) is most sensitive to changes of the total accessible filler surface area at low strain amplitudes (γ0 = 0.32). The addition of up to 70 phr CB leads to an increase of I3/1(φ) by a factor of more than ten. The influence of the measurement temperature on I3/1 is pronounced for CB levels above the percolation threshold.

Aging of natural rubber studied via Fourier-transform rheology and double quantum NMR to correlate local chain dynamics with macroscopic mechanical response

“…In the I 3/1 (γ 0 ) of NRCB1, there is a peak around γ 0 = 0.1%. Similar peaks are also observed from polymer melts [18] and unvulcanized rubbers [21]. However, the origin is still not clear.…”

“…At small strain amplitudes, I 3/1 (γ 0 ) of both NR1 and NRCB1 was dominated by noise with a slope of −1 in the double logarithmic scale as indicated in Fig. 2 (the lower graph), a typical phenomenon observed in FT-Rheology [16][17][18][19][20][21]. In this region, the small torque response from the measurement is beyond the resolution of the torque transducer.…”

“…Parameters such as the relative intensity of the 3rd harmonic, I 3/1 (γ 0 ), can be used as the simplest way to measure rheological nonlinearity at specified oscillatory deformation frequency and strain amplitude. Thereafter, FT-Rheology has been applied to study rheological nonlinearity of various soft materials, including polymer melts [18], polymer blends [19] and rubber compounds in unvulcanised state [20,21], but not yet crosslinked rubber and its aged products.…”

Nonlinear “oddities” at the percolation of 3D hierarchical graphene polymer nanocomposites

“…The literature survey is limited to thermoplastic nanocomposites tested in standard rotational rheometry. However, it should be noted that FT-Rheology has been applied to polymer composites and rubber-based composites and nanocomposites, e.g., see Leblanc (2006a, b) and Schwab et al (2016). The range of polymernanofiller combinations cited in Table 1 reflects systems that generally provide good dispersion properties.…”

Rheological behavior of fumed silica filled polyethylene oxide

“…The nonlinearity of nanocomposites appears to involve the superposition of two responses arising from the matrix and the "filler." 73 Although the filler may enhance the nonlinear response of the matrix, 74 this additional nonlinearity is not clearly related to FS content and type. Nevertheless, the results in Figures 10 and 11 show that Lissajous plots are centrally symmetric and in the most cases the portion of firstorder harmonic amplitude to the stress is higher than 60% at γ = 80%, indicating that the measured G' and G" allow discussing the Payne effect rather reasonably.…”