Reinforcement chain slippage mechanism

Figure 10.15. Schematic illustrations of theories of stress softening, (a) Mullins and Tobin (1956) considered the filled rubber as a heterogeneous system comprised of hard and soft phases. Deformation breaks down the hard phase, but the degree of breakdown depends on the maximum extension of the sample, (b) F. Bueche (1965) attributed stress-softening to the breakage of network chains attached to adjacent filler particles (A molecule breaks first), (c) Dannenberg (1966) and Boonstra (1965) suggested that reinforcement can be understood through chain slippage mechanisms. The slippage is shown by the chain marks. (Smith and Rinde, 1969.)...

These reinforcing fillers, with dimensions of the order of 100 to 200 A, form a variety of physical and chemical bonds with the polymer chains. Tensile and tear strength are increased, and the modulus is raised (154-158). The reinforcement can be understood through chain slippage mechanisms (see Figure 9.34) (137). The filler permits local chain segment motion but restricts actual flow. 

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