Elastomers Payne effect

Even dynamic measurements have been made on mixtures of carbon black with decane and liquid paraffin [22], carbon black suspensions in ethylene vinylacetate copolymers [23], or on clay/water systems [24,25]. The corresponding results show that the storage modulus decreases with dynamic amplitude in a manner similar to that of conventional rubber (e.g., NR/carbon blacks). This demonstrates the existence and properties of physical carbon black structures in the absence of rubber. Further, these results indicate that structure effects of the filler determine the Payne-effect primarily. The elastomer seems to act merely as a dispersing medium that influences the magnitude of agglomeration and distribution of filler, but does not have visible influence on the overall characteristics of three-dimensional filler networks or filler clusters, respectively. The elastomer matrix allows the filler structure to reform after breakdown with increasing strain amplitude. 

Non-linear viscoelastic properties were observed for fumed silica-poly(vinyl acetate) (PVAc) composites, with varying PVAc molar mass and including a PVAc copolymer with vinyl alcohol. Dynamic mechanical moduli were measured at low strains and found to decrease with strain depending on surface treatment of the silica. The loss modulus decreased significantly with filler surface treatment and more so with lower molar mass polymer. Copolymers with vinyl alcohol presumably increased interactions with silica and decreased non-linearity. Percolation network formation or agglomeration by silica were less important than silica-polymer interactions. Silica-polymer interactions were proposed to form trapped entanglements. The reinforcement and nonlinear viscoelastic characteristics of PVAc and its vinyl alcohol copolymer were similar to observations of the Payne effect in filled elastomers, characteristic of conformations and constraints of macromolecules. ... 

The modulus at minimum and low strain amplitudes is due to the so-called filler network and it is accepted that the filler surface area, as well as the surface activity, play a major role in establishing a filler network, determining the effective contact area between filler particles and between filler particles and the elastomer matrix. The stress assisted disruption of the filler network causes the reduction of the modulus as the strain amplitude increases, giving rise to the non-linearity of the dynamic-mechanical behaviour of the rubber composite. This phenomenon is known as the Payne effect and it is (to a certain extent) reversible. The disruption and re-formation of the filler network is... 

Wang, J. Hamed, G. R. Umetsu, K. Roland, C. M., The Payne Effect in Double Network Elastomers. Rubber Chem. Technol. 2005, 78, 76-83. 

Merabia S, Sofia P, Long DR (2008) A microscopic model fm the reinforcement and the nonlinear behavim of filled elastomers and thermoplastic elastomers (Payne and Mullins Effects). Macnnnolecules 41 8252-8266... 

Very recently our group has explored the non linear viscoelastic effects in filled elastomers as Ponnamma et al. [10, 11] and Sadasivuni et al. [12] report Payne effect in 2D filler reinforced elastomers. This chapter aims in investigating the effect of layered silicates and graphene nanolayers on various elastomer matrices based on various filler concentrations and filler-matrix interactions. 

The addition of iso-dimensional nanofillers into elastomers causes many changes in mechanical and physical properties, but especially, the effect of nanoparticles on the nonlinear viscoelasticity properties of rubbers has been investigated. In rubber matrices containing nanofillers, exhibition of the Payne effect is strongly connected with the dispersion of the nanofiller and the tendency to create aggregates among the nanoparticles. Filler dispersion plays an important role in determining the nonlinear viscoelastic behavior of these systems— in particular, both the properties of the filler particles and filler-polymer compatibility. 

Wang J, Hamed GR, Umetsu K, Roland CM (2005) The Payne effect in double betwork elastomers. Rubber Chem Technol 78(l) 76-83... 

Apart from the standard phenomenology described in the previous section, carbon black filled elastomers present some effects peculiar of this class of materials. These effects are the Mullins effect, which concerns the quasistatic behavior, and the Payne effect, dealing with the dynamic response. 

Fig. 26 Strain dependence of the storage and loss moduli (Payne effect) at 70 °C and 10 Hz for a rubber compound with different concentration of carbon black filler [7]. The graphs suggest a monotonic dependence of the dynamic moduli on the filler content in the range 4> e [0 70] phr. The Payne effect becomes unnoticeable for low reinforced elastomers e [0 lOjphr)...

Chazeau L, Brown JD, Yanyo LC, Stemstein SS (2000) Modulus recovery kinetics and other insights into the Payne effect for filled elastomers. Polym Compos 21 202-222... 

Drozdov A D and Dorfmann A (2002) The Payne effect for particle-reinforced elastomers, Polym Eng Sci 42 591-604. 

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