Coaxial electrospinning process toward optimal nanoparticle dispersion in polymeric matrix

Abstract

Nanoreinforced polymers have gained popularity in the last decades since they exhibit enhanced properties (compared to pristine polymers) that are useful in a wide range of applications. Unfortunately, dispersion of nanoparticles (NPs) into polymeric matrices is a major problem since they tend to form agglomerates, limiting the improvement of properties and further applications. In this work, we propose the use of coaxial electrospinning as one-step method to disperse NPs in a polymeric matrix. Particularly, iron oxide (Fe 3 O 4) NP with a monomodal and bimodal size distributions were dispersed in polyvinylidene fluoride (PVDF), a material that is well known for its improved piezoelectric properties when it is processed via electrospinning. The results indicate that the incorporation of NP modified the polymeric fiber depending on their surface-to-volume ratio (smaller NP promoted smaller fiber size). Moreover, transmission electron microscopy revealed a good NP dispersion in the polymer, especially for the smallest NP size (monomodal). Finally, each NP size distributions were well preserved in the electrospun mats compared to the initial NP solutions, demonstrating the suitability of this technique for the fabrication of nanoreinforced PVDF structures with tailored NP size. Overall, this method could represent a facile and practical alternative to fabricate materials with piezoelectric/super-paramagnetic properties.

Polyurethane-Coated Polyaniline/SiO2 Nanoparticle Electrospun Nanofiber Membranes for Waterproof and Moisture-Permeable Materials

“…However, when the SiO 2 content increased to 80 mg·mL –1 , the fiber diameter began to be uneven and increased significantly (Figure S3a). This was because too much SiO 2 nanoparticles destroyed the continuity of the polymer matrix and hindered the stretching force acting on the polymer ejecting jet during electrospinning …”

“…This was because too much SiO 2 nanoparticles destroyed the continuity of the polymer matrix and hindered the stretching force acting on the polymer ejecting jet during electrospinning. 35 The surface Si element content of the PAN/SiO 2 −PU membranes was characterized by EDS mapping, as shown in Figure 7a−d. It can be seen that the Si element on the fiber surface increased with increasing SiO 2 content in the shell solution.…”

Electrospun Composite Nanofibers for Functional Applications

“…Navarro Oliva and co-workers prepared core-shell-structured NNHs by the coaxial electrostatic spinning technique using an Fe 3 O 4 solution as the core layer and a PVDF polymer solution as the shell layer. As shown in Figure 4B, TEM images showed that the NPs were uniformly dispersed inside the fibers without agglomeration [84]. Combining both electrospinning and electrospraying to prepare NNHs is also a convenient method.…”

Core–Shell Copper Azide-Based Nanofiber Films Prepared by Coaxial Electrospinning for MEMS Microinitiators

“…The CA films with high electrostatic safety suitable for MEMS microinitiators were then obtained via high-temperature carbonization and in situ azide processes. When compared to the traditional electrospinning technology, the coaxial electrospinning process can produce materials that cannot be electrospun individually into new nanofibers, as well as core–shell nanofibers. − This core–shell structure allows a carbon shell to be wrapped around the fibers’ surface, providing double protection for the CA and reducing its electrostatic sensitivity even further. Furthermore, the CA-based film can successfully detonate secondary explosives if the energy and sensitivity requirements are met, effectively alleviating the problem of powder samples being difficult to process and form.…”