Influence of Multiwall Carbon Nanotubes Trapped at the Interface of an Immiscible Polymer Blend on Interfacial Tension

The influence on interfacial energy of multiwall unfunctionalized carbon nanotubes (CNTs) trapped at the interface of an immiscible blend of polyamide 12 (PA12) and acrylate-ethylene (EA) copolymer is investigated with the help of the Palierne model combined with transmission electron microscopy (TEM) observations. It is found that the interfacial energy is unaffected by the interfacially trapped CNTs. The reduced droplet size observed in the presence of CNTs can neither be ascribed to a classical compatibilizer effect due to lower interfacial energy leading to enhanced breakup during processing, nor to the minute changes of the continuous phase viscosity induced by the CNTs. Another explanation based on steric hindrance is proposed. A network CNT layer that acts as a rigid shell is formed, which prevents coalescence of colliding droplets.