Synthesis and Thermomechanical Characterization of Nylon 6/Cu Nanocomposites Produced by an Ultrasound‐Assisted Extrusion Method

Abstract

A nylon 6 nanocomposite with copper nanoparticles processed by ultrasound-assisted extrusion was prepared at concentrations between 0.01 and 0.50 wt.%, and its thermal and mechanical properties were determined. The presence of the crystalline phase α (α1 and α2) in the polymer matrix was confirmed by X-ray diffraction, and the presence of the α2 phase showed a greater increase than the α1 phase as a function of the copper nanoparticle concentration. This process was attributed to secondary crystallization. Furthermore, it was determined that the chemical composition of the nanoparticles is a blend of metallic copper and cupric oxide. The formation of copper nanowires was observed by scanning electron microscopy, and the concentration of 0.10% exhibited the best dispersion in comparison with the other concentrations. The melting temperature of the nanocomposites underwent a slight decrease in comparison with the nylon 6, while thermal stability, crystallization temperature, and crystallinity were increased in relation to the pure polymer. This behavior is attributed to an efficient dispersion of the nanoparticles and to their functionality as crystal nucleation sites. For the 0.10% concentration nanocomposite, higher mechanical properties were obtained; tensile strength increased by 8.9%, and the tensile modulus increased by 25.4%; as a consequence, elongation at break was 62% less than that of the polymer matrix.

Melt-Mixed Thermoplastic Nanocomposite Containing Carbon Nanotubes and Titanium Dioxide for Flame Retardancy Applications

“…The coalescence is not exclusive to TiO 2 NPs. The spherical copper nanoparticles (Cu NPs), with an average size of 21 nm when they are processed to obtain Nylon 6/Cu nanocomposites, increased their size and formed aggregates in form of wire [60].…”

Antimicrobial Property of Polypropylene Composites and Functionalized Copper Nanoparticles

“…The aggregation of NPs in a polymeric matrix is associated with its high surface energy. Typically, the formation of large NP aggregates involves a decrease in the mechanical, thermal, and antimicrobial properties of the composite [ 27 ].…”

“…Our research group has reported the obtention of functionalized CuNPs with nitrogenated ligands [ 32 , 33 , 34 ]. These modified CuNPs were employed successfully to prepare polymeric composites with nylon 6, achieving an improvement in the mechanical properties of this polymer with a low concentration of the copper nanoparticles [ 27 ]. It is expected that these composites exhibit good antimicrobial properties due to the combination of the polar nature of the polymeric matrix with the functionalized CuNPs with nitrogenated ligands.…”

Synthesis of Nylon 6/Modified Carbon Black Nanocomposites for Application in Uric Acid Adsorption

“…The dispersion mechanism depends on the conditions of the ultrasonic treatment. Conventional fixed frequency ultrasonic application has been used for more than 20 years [ 19 , 20 , 21 ]. However, due to the high viscosity of molten polymers, this mechanism is not sufficient for improving particle dispersion and deagglomeration.…”

“…The incorporation of NPs into the Nylon 6 matrix affects the physicochemical and mechanical properties of nanocomposites. Nylon 6 nanocomposites with NPs of different natures have been reported [ 21 , 23 , 24 , 25 , 26 , 27 ].…”