Fecha de publicación: -- Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE Ultralow graphene nanoplatelet contents enhance the mechanical and thermomechanical performance of PA6 nanocomposites, while the precipitation route strongly influences their behavior. Despite containing only 0.011–0.026 wt% GNP, the materials exhibit improved strength, stiffness, crystallization kinetics, and high-temperature strain resistance, highlighting processing strategy as a key factor in nanocomposite performance.

ABSTRACT
In this research, nanocomposites of polyamide 6 (PA6) reinforced with different contents of graphene nanoplatelets (GNP) were developed. Initially, the GNP was dispersed in a PA6 matrix through the solution mixing process, and two distinct precipitation methods were employed during the solvent removal step to subsequently obtain the masterbatches: emulsion precipitation and precipitation. Afterward, the PA6/GNP nanocomposites were prepared by a melt-blending process, where 5% of the masterbatch was diluted in PA6. The produced materials were characterized through mechanical, thermal, rheological, and morphological tests. The results revealed that GNP reinforcement enhanced mechanical properties, particularly tensile strength, flexural strength, and flexural modulus, up to 26.8%, 19%, and 30.3%, respectively. Additionally, dynamic mechanical analysis demonstrated improvements of the nanocomposites in storage modulus at 23°C and 100°C, heat deflection temperatures, and strain resistance at 100°C and 200°C. Therefore, the results highlighted that the addition of graphene nanoplatelets and the precipitation method used are relevant to the nanocomposite properties.