Payne effect of silica-filled styrene-butadiene rubber

Publication date: 5 May 2017
Source:Polymer, Volume 116
Author(s): Ruiquan Yang, Yihu Song, Qiang Zheng
Filling significantly reinforces rubbers and introduces rheological nonlinearity, which is usually ascribed to filler networking and destructuring effects while conceptual conflicts still exist. Herein nonlinear rheology of compounds of fumed silica filled emulsion-polymerized styrene butadiene rubber is investigated with respect to silica type (hydrophilic and hydrophobic) and loading. The results revealed that, at low silica loadings, the reinforcement is involved in strain amplification effect and the rheological nonlinearity is initiated by a critical microscopic strain of bulk rubber matrix or a critical stress of the compounds. At high silica loadings when silica tends to develop an agglomerated structure, the reinforcement efficiency and the critical stress for onset of nonlinearity are reduced notably. Instead, an overshoot of loss modulus occurs accompanying with onset of nonlinearity involved in additional dissipation of mechanical energy possibly arising from friction among silica particles in their agglomerates.

Graphical abstract

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