Electrospun Thermosetting Carbon Nanotube–Epoxy Nanofibers

Abstract

This paper represents the process of fabrication and characterization of submicron carbon nanotube (CNT)–epoxy nanocomposite filaments through an electrospinning process. Electrospinning is one of the most versatile, inexpensive, and environmentally well-known techniques for producing continuous fibers from submicron diameter all the way to tens of nanometer diameter. Here, electrospinning of submicron epoxy filaments was made possible by partial curing of the epoxy by mixing the hardener and through a thermal treatment process without the need for adding any plasticizers or thermoplastic binders. This semicuring approach makes the epoxy solution viscous enough for the electrospinning process, that is, without any solidification or nonuniformity caused by the presence of the hardener inside the mixture. The filaments were spun using a CNT/epoxy solution with a viscosity of 65 p using 16 kV and a collector distance of 10 cm. The diameter of these filaments can be tuned as low as 100 nm with adjustment of electrospinning parameters. By incorporating a low amount of CNT into epoxy, better structural, electrical, and thermal stabilities were achieved. The CNT fibers have been aligned inside the epoxy filaments because of the presence of the electrostatic field during the electrospinning process. The modulus of the epoxy and CNT/epoxy filaments were found to be 3.24 and 4.84 GPa, respectively. The presence of the CNT can lead up to 49% improvement on modulus. Accordingly, using a commercially available epoxy suitable for industrial composite productions makes the developed filament suitable for many applications.

Higher strength carbon fiber lithium‐ion polymer battery embedded multifunctional composites for structural applications

“…DMF and Triton‐X used in the experiments have been provided by Sigma‐Aldrich, unless it is noted. CNT (4W) with epoxy (w/w) was optimized in our previous studies 49,50 . To acquire a uniform and well‐dispersed CNT polymer solution, high power probe sonication was used in continuous time periods (40 s on, 30 s off for 2 h).…”

“…CNT (4W) with epoxy (w/w) was optimized in our previous studies. 49,50 To acquire a uniform and well-dispersed CNT polymer solution, high power probe sonication was used in continuous time periods (40 s on, 30 s off for 2 h). Next, a curing agent was added to the mixture (20:1 w/w) with a resting time of 20 h to make a semicured solution with the viscosity 65p necessary for the electrospinning method.…”

“…The electrospun CFRP sample showed the farthest flexural strength and modulus compared to the control CFRP samples, as shown in Figure 7. The CNT/Epoxy electrospun-enhanced CFRP specimen was considered due to prior research experiments conducted by our group, 49,50 demonstrating that incorporating of nanofiber reinforcement mats increases flexural properties. The Li-Po battery packaging in electrospun CFRP and control CFRP-based MESC showed flexural strength of 10 and 80 MPa, respectively, which is more than 33% increment.…”

Stimuli‐Responsive Electrospun Fluorescent Fibers Augmented with Aggregation‐Induced Emission (AIE) for Smart Applications

“…[ 201 , 202 , 203 ] However, the electrospun fibers of thermosetting polymers are difficult to fabricate due to the crosslinked nature of the polymeric chains. [ 204 , 205 ] When thermosetting polymer is combined with a curing agent, it starts to crosslink kinetically and with time and temperature, the viscosity of the resin increases. Due to the increase of viscosity with the extent of crosslinking, it is difficult to form a Taylor cone when exposed to an electric field in the electrospinning setup (Figure 3a inset), making electrospinning difficult to accomplish.…”

Epoxide Cross-Linked and Lysine-Blocked Zein Ultrafine Fibrous Scaffolds with Prominent Wet Stability and Cytocompatibility

“…Epoxides, with special epoxy groups, have been widely exploited as the matrix of composites, coating agents, and adhesives. − Benefiting from the strained bond angles and the polarization of the C–C and C–O bonds, the epoxy groups display extremely high reactivities with a wide variety of substrates under diverse conditions. Epoxy reactions are usually based on the nucleophilic mechanism .…”