Exploring the mechanical, rheological, and thermal performance of self-reinforced composites based on polyamides and multi-walled carbon nanotubes

Self-reinforced composites (SRCs) based on different blends of PA6, PA12, and multi-walled carbon nanotubes (MWCNTs) as matrices and a PA6.6 plain woven fabric as reinforcement were prepared by the film stacking method. The morphology of the SRCs was analyzed using optical and scanning electron microscopy, both on cryo-fractured and included polished cross-sections samples. Rheological measurements were performed to assess the materials microstructure and thermal stability. In addition, uniaxial tensile tests were carried out to determine mechanical properties such as stiffness, strength, strain at break, and tensile toughness. The assessment of failure mechanisms was performed through acoustic emission in situ during tensile tests. Furthermore, fracture tests were carried out to evaluate the impact of incorporating MWCNTs on SRCs failure and fracture behavior. The obtained results suggest a notable improvement in the mechanical properties of the SRCs compared with the matrices, that is, tensile strength increased by 132% for SRC-0, 83% for SRC-0.5, 54% for SRC-2.5, and only by 13% for SRC-8. This study indicates that these SRCs appear as promising materials for high performance applications, which also require multifunctional characteristics. Researchers have developed self-reinforced composites based on PA6/PA12/MWCNTs blends as matrix and a PA6.6 fabric as reinforcement resulting in improved mechanical properties, such as increased strength and stiffness. The relationship between CNTs content and composite behavior offers opportunities for additional research optimizing CNT loading and processing for optimal performance, leading to customized nanocomposites for high performance applications. image