Rheology of ethylene-vinyl acetate composites tuned by crosslinked rubber particles and carbon nanotubes

Rheology of polymer composites is crucial for production efficiency and performance of final products. Investigated here is influence of crosslinked rubber particles (CRPs) and carbon nanotubes (CNTs) on rheology of ethylene-vinyl acetate (EVA) composites. Transmission electron microscopy shows that CNTs are enriched in the EVA phase and do not penetrate into the CRPs. The reinforcement profiles of CRPs and CNTs are analyzed with the aid of time-concentration superposition principle, indicating that the reinforcement effects of these fillers are additive. While CNTs intensify and accelerate strain softening, CRPs are able to delay and weaken this effect. The synchronous evaluation of electrical resistance and rheology reveals that the conductive and rheological percolation networks are not entirely equivalent. The addition of CRPs improves elasticity and rheological and electrical recoveries of CNTs-based composites. The findings suggest that the combination of the two fillers synergistically improves composite properties, offering a foundation for optimizing advanced processing and application requirements.