Modeling of solvent evaporation from polymer jets in electrospinning

Wu, Xiang‐Fa; Salkovskiy, Yury; Dzenis, Yuris A.

doi:10.1063/1.3585148

Cited by 75 publications

(58 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This would be consistent with the presence of a slowly evaporating solvent component, i.e. with a jet time-of-flight which is comparable with the drying time scale, 35,37 and supported by the joints observed in SEM micrographs of intersecting deposited fibers (e.g., Figure 1b,c).…”

Section: Resultssupporting

confidence: 80%

Conformational Evolution of Elongated Polymer Solutions Tailors the Polarization of Light-Emission from Organic Nanofibers

et al. 2014

View full text Add to dashboard Cite

Polymer fibers are currently exploited in tremendously important technologies. Their innovative properties are mainly determined by the behavior of the polymer macromolecules under the elongation induced by external mechanical or electrostatic forces, characterizing the fiber drawing process. Although enhanced physical properties were observed in polymer fibers produced under strong stretching conditions, studies of the process-induced nanoscale organization of the polymer molecules are not available, and most of fiber properties are still obtained on an empirical basis. Here we reveal the orientational properties of semiflexible polymers in electrospun nanofibers, which allow the polarization properties of active fibers to be finely controlled. Modeling and simulations of the conformational evolution of the polymer chains during electrostatic elongation of semidilute solutions demonstrate that the molecules stretch almost fully within less than 1 mm from jet start, increasing polymer axial orientation at the jet center. The nanoscale mapping of the local dichroism of individual fibers by polarized near-field optical microscopy unveils for the first time the presence of an internal spatial variation of the molecular order, namely the presence of a core with axially aligned molecules and a sheath with almost radially oriented molecules. These results allow important and specific fiber properties to be manipulated and tailored, as here demonstrated for the polarization of emitted light.

show abstract

Section: Resultssupporting

confidence: 80%

Conformational Evolution of Elongated Polymer Solutions Tailors the Polarization of Light-Emission from Organic Nanofibers

et al. 2014

View full text Add to dashboard Cite

show abstract

“…Variability in mechanical properties of fibers within a single synthetic batch may be due to inherent sample heterogeneity introduced by the stochastic electrospinning process (34). Studies have shown that electrospun fibers dry very rapidly as they are drawn through a spatially varying electric field (35), causing them to experience heterogeneous tensile forces and develop highly varying structures (36). The error bar in the Young's modulus also increased with concentration, likely due to nanoparticle aggregates increasing the heterogeneity of the nanocomposite morphology and acting as nucleation sites for defects.…”

mentioning

confidence: 99%

Influence of three-dimensional nanoparticle branching on the Young’s modulus of nanocomposites: Effect of interface orientation

Raja

Olson²,

Limaye³

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

With the availability of nanoparticles with controlled size and shape, there has been renewed interest in the mechanical properties of polymer/nanoparticle blends. Despite the large number of theoretical studies, the effect of branching for nanofillers tens of nanometers in size on the elastic stiffness of these composite materials has received limited attention. Here, we examine the Young's modulus of nanocomposites based on a common block copolymer (BCP) blended with linear nanorods and nanoscale tetrapod Quantum Dots (tQDs), in electrospun fibers and thin films. We use a phenomenological lattice spring model (LSM) as a guide in understanding the changes in the Young's modulus of such composites as a function of filler shape. Reasonable agreement is achieved between the LSM and the experimental results for both nanoparticle shapes-with only a few key physical assumptions in both films and fibers-providing insight into the design of new nanocomposites and assisting in the development of a qualitative mechanistic understanding of their properties. The tQDs impart the greatest improvements, enhancing the Young's modulus by a factor of 2.5 at 20 wt.%. This is 1.5 times higher than identical composites containing nanorods. An unexpected finding from the simulations is that both the orientation of the nanoscale filler and the orientation of X-type covalent bonds at the nanoparticle-ligand interface are important for optimizing the mechanical properties of the nanocomposites. The tQD provides an orientational optimization of the interfacial and filler bonds arising from its three-dimensional branched shape unseen before in nanocomposites with inorganic nanofillers.three-dimensional nanoparticle branching | polymer fibers | nanocomposite films | lattice spring model | tetrapod quantum dot P olymer−nanoparticle composites have become a highly active topic of research with rapidly expanding applications (1), in part because of their high polymer−particle interfacial area and the unique shape-and size-dependent, tunable properties of nanoparticle reinforcements. For example, new polymer nanocomposites have been developed that can optically sense stress concentration (2), are responsive to magnetic, electrical, and thermal actuation (3, 4), and exhibit large changes in elastic modulus and glass transition temperature at low nanoparticle concentrations (5).While theoretical studies show that the Young's modulus of such polymer nanocomposites depends on nanoparticle shape (6), experimental studies are limited. Experimental studies on polymers (7) include the synergistic reinforcement effects of multiple nanocarbons (8) and the shape-dependent reinforcement effects of micrometer-sized tetrapods (9), microscale ceramic needles (10), carbon nanotubes (11), clay-based nanocomposites (12, 13), and others (14). Computational studies include the effects of nanoparticle packing and size on the nanocomposite Young's modulus (15-17). However, the effects of increasing nanoparticle branching on the mechanical behavior of nanocomposite...

show abstract

“…Electrospinning is a promising technique to manufacture superfine fibers and has attracted a great deal of attentions in recent decade. [1][2][3][4][5][6][7][8][9][10][11][12] In this procedure, the polymer solution is pumped through a syringe needle, and subsequently, is ejected to form a thin jet under the action of electrostatic force imposed by a high-voltage electric field, then the stretched polymer fibers dissolved in the spinning solution are deposited on the collector after the solvent evaporates almost completely. Thus, controlling the morphology of fibers in spinning solution and adjusting the evaporation rate are especially important for preparing the high-quality fiber.…”

mentioning

confidence: 99%

Microscopic mechanism for the effect of adding salt on electrospinning by molecular dynamics simulations

Wang

2014

Applied Physics Letters

View full text Add to dashboard Cite

Adding salts into polymer solution has been found to modulate the fiber structure and significantly improve the solution spinnability in electrospinning. However, the mechanisms have not been fully understood. This work adopted molecular dynamics method to investigate the dynamic behavior of poly(ethylene oxide) (PEO)/water droplet with or without dissolved NaCl salt under high-voltage electric field. Our simulation results agreed with the previous experimental reports well. We observed that some daughter droplets detach from the mother droplet due to the ions evaporation and hydration effect, which significantly accelerates the water evaporation and hence improves the solution spinnability. We also observed that some sodium ions are always coordinated with the ether oxygen group in the PEO chain. When these ions are accelerated by the electric field, the PEO chain segments follow the motion of the ions, inevitably stretching the chain and improving the fiber morphology.

show abstract

Modeling of solvent evaporation from polymer jets in electrospinning

Cited by 75 publications

References 30 publications

Conformational Evolution of Elongated Polymer Solutions Tailors the Polarization of Light-Emission from Organic Nanofibers

Conformational Evolution of Elongated Polymer Solutions Tailors the Polarization of Light-Emission from Organic Nanofibers

Influence of three-dimensional nanoparticle branching on the Young’s modulus of nanocomposites: Effect of interface orientation

Microscopic mechanism for the effect of adding salt on electrospinning by molecular dynamics simulations

Contact Info

Product

Resources

About