High-Strength GO/PA66 Nanocomposite Fibers via In Situ Precipitation and Polymerization

Abstract

The uniform dispersion of graphene oxide (GO) and strong interfacial bonding are the key factors in achieving the high mechanical strength of GO/polymer composites. It is still challenging to prepare GO/PA66 composites with uniform GO dispersion by the in situ polymerization method. In this paper, we prepare GO/PA66 salt nanocomposite by in situ precipitating PA66 salt with GO in ethanol. The GO/PA66 nanocomposite fibers are then fabricated using the as-prepared GO/PA66 salt by in situ polymerizing and melt spinning. By tuning the GO content, the tensile strength and Young’s modulus of the GO/PA66 fibers are increased from 265 ± 18 to 710 ± 14 MPa (containing 0.3 wt% GO) and from 1.1 ± 0.08 to 3.8 ± 0.19 GPa (containing 0.5 wt% GO), respectively. The remarkable improvements are attributed to the uniform dispersion of GO in the GO/PA66 salt nanocomposite via ionic bonding and hydrogen bonding in the in situ precipitation process, and the covalent interfacial bonding between the GO and PA66 during the in situ polymerization process. This work sheds light on the easy fabrication of high-performance PA66-based nanocomposites.

Application of Solution Blow Spinning for Rapid Fabrication of Gelatin/Nylon 66 Nanofibrous Film

“…For the GA film, the broad stretching band at 3000 to 3750 cm −1 (amide A) was related to N-H stretching vibrations and O-H, and three characteristic peaks of GA were observed at around 1647 cm −1 (amide I) corresponding to C=O and C-N stretching vibrations, 1542 cm −1 (amide II) corresponding to N-H bending and C-H stretching vibration, and 1259 cm −1 (amide III) [9,36]. For PA66 film, the adsorption peak appearing at 3305 cm −1 belonged to the N-H stretching band of amine group and the peaks at 1641 cm −1 and 1540 cm −1 [37]; and the characteristic peak at 2934 cm −1 corresponding to the stretching vibration of C-H also confirmed solid evidence of the existence of PA66 [38]. The absence of peak splitting in all mixed nanofibers indicates that gelatin and PA66 were uniformly dispersed in the fibers.…”

“…Figure 2b shows the XRD results of the GA, PA66 films and GA/PA66 films with various weight ratios. PA66 has two obvious diffraction peaks at around 2θ = 20.1° ascribed to the interchain hydrogen bond plane of the amide group [29] and 2θ = 23.7°, which is similar to the results of Noguchi's study [39]; whereas gelatin had a broad diffraction peak at 2θ = 19.2°, suggesting a low crystallinity of GA. For the GA/PA66 composite films, two diffraction peaks appeared between 20° and 25°, which were corresponding to the two characteristic peaks (α1 and α2) of the α-crystalline form of PA66 [38]. It was noticeable that the intensity of the peaks of the GA/PA66 composite film was enhanced compared to the pure GA film, suggesting that the crystallization of the GA/PA66 composite films was advanced with the addition of PA66.…”

PMMA-Grafted Calcium Sulfate Whiskers for Applications as Fillers in PVC

“…Studies have shown that increasing the alkyl chain length of the surface improves the interactions between the particles and the polymer matrix [ 27 ]. Therefore, several works proposed modifying inorganic filler particles with long-chain polymers [ 28 , 29 , 30 ]. Grafting such polymers on the particle surfaces has several advantages.…”

Aminated Graphene-Graft-Oligo(Glutamic Acid) /Poly(ε-Caprolactone) Composites: Preparation, Characterization and Biological Evaluation

“…Furthermore, GO and rGO can give more stable dispersions in water and polar solvents than graphene. In particular, Gu et al reported the modification of GO with polyamide in ethanol followed by melt spinning [ 35 ]. The developed composites provided excellent mechanical properties.…”