Validation of rheological responses for morphological evaluation of incompatible polyamide 12/thermoplastic elastomer blends filled with nanoclay

The interrelationship between viscoelastic responses and multiphasic morphology in compatibilized PA 12/nanoclay/SBS nanocomposites has been investigated. Different effects of material parameters including nanoclay, SBS rubber and compatibilizer contents on the rheology and morphology correlations have been evaluated. The findings showed that the solid like and shear thinning behavior along with relaxation time and Casson yield stress intensify at higher contents of nanoclay and SBS rubber. By increasing the SBS level, smaller rubber particles with narrower size distribution were obtained that was in agreement with the rheological properties. Nonetheless, the incorporation of more nanoclay effectively resulted in finer matrix/dispersed morphology just in the presence of larger compatibilizer contents. Although m-SEBS influenced the biphasic morphology similar to common compatibilizers, the non-terminal behavior of the nanocomposites weakened at higher m-SEBS levels due to the stronger compatibilizer effect on the chain confinement in nanoclay galleries than the one on the PA12/SBS rubber interfacial adhesion.