Mullins Effect

The Mullins effect is a phenomenon observed in rubber materials where the equilibrium stress-strain response softens with strain history (visco-elastic softening effect).
In contrast to the Payne effect, the Mullins effect can occur in filled and unfilled rubber materials.

When does the Mullins effect occur?

The Mullins effect is a particular aspect of the mechanical response in filled rubbers, in which the stress-strain depends on the maximum load previously encountered. It is an instantaneous softening process, which is irreversible.

The Mullins effect occurs whenever the load increases beyond its prior all-time maximum value.
The Mullins effect can be measured with the NETZSCH DMA GABO EPLEXOR®.

The figure below depicts rubbers with fillers. The Mullins effect causes the macromolecular chains to deteriorate and the filler particles to separate from each other destroying the elastomer.


Related Methods

DMA