Analysis of Electrospinning Nanofibers: Diameter Distribution, Process Dynamics, and Control

Author(s):  
Xuri Yan ◽  
Michael Gevelber

Electrospinning is a method of producing nanometer scale fibers by accelerating a jet of charged polymer solution in an electric field. In many emerging, high value electrospinning applications, such as the biomedical area, the diameter distribution of electrospun polymeric nanofibers has important implications for the product’s performance and process economics (in terms of yield and production rate). However, the current state-of-the-art electrospinning process results in unpredictable and time varying diameter distributions, both during a run and run-to-run. Thus, this work is focused on developing an appropriate control system to achieve consistent and controllable fiber diameters. Another goal of this work is to develop a better understanding of the relation between process physics and the resulting fiber diameter characteristics. To address these problems, a well instrumented and computer based actuator control system has been developed. The effects of process parameters on fiber diameter are investigated for achieving consistent and repeatable process capability. The fundamental process dynamics are identified and the relation between measurable variables and the resulting fiber diameter distribution is analyzed. This relation provides the basis of developing appropriate control strategies in order to reduce both the process variations from run-to-run and during a run.

Author(s):  
Xuri Yan ◽  
Michael Gevelber

In many emerging, high value electrospinning applications, the diameter distribution of electrospun fibers has important implications for the product’s performance and process reproducibility. However, the current state-of-the-art electrospinning process results in diameter distribution variations, both during a run and run-to-run. To address these problems, a vision-based, open loop system has been developed to better understand the process dynamics. The effects of process parameters on fiber diameter distributions are investigated, process dynamics are identified, and the relation between measurable variables and the resulting fiber diameter distribution is analyzed.


2006 ◽  
Vol 948 ◽  
Author(s):  
Xuri Yan ◽  
Michael Gevelber ◽  
Jian Yu ◽  
Gregory Rutledge

ABSTRACTAn integrated data acquisition/actuator control system is developed to conduct experiments investigating the fundamental dynamics for different operating conditions in an electrospinning system. The relation between measured variables (fiber current, whipping angle, jet length, and expulsion cone volume) to the resulting fiber diameter distribution is analyzed.


Nanomaterials ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 1526 ◽  
Author(s):  
Ronaldo P. Parreño ◽  
Ying-Ling Liu ◽  
Arnel B. Beltran

This study demonstrated the processability of sulfur copolymers (SDIB) into polymer blend with polybenzoxazines (PBz) and their compatibility with the electrospinning process. Synthesis of SDIB was conducted via inverse vulcanization using elemental sulfur (S8). Polymer blends produced by simply mixing with varying concentration of SDIB (5 and 10 wt%) and fixed concentration of PBz (10 wt%) exhibited homogeneity and a single-phase structure capable of forming nanofibers. Nanofiber mats were characterized to determine the blending effect on the microstructure and final properties. Fiber diameter increased and exhibited non-uniform, broader fiber diameter distribution with increased SDIB. Microstructures of mats based on SEM images showed the occurrence of partial aggregation and conglutination with each fiber. Incorporation of SDIB were confirmed from EDX which was in agreement with the amount of SDIB relative to the sulfur peak in the spectra. Spectroscopy further confirmed that SDIB did not affect the chemistry of PBz but the presence of special interaction benefited miscibility. Two distinct glass transition temperatures of 97 °C and 280 °C indicated that new material was produced from the blend while the water contact angle of the fibers was reduced from 130° to 82° which became quite hydrophilic. Blending of SDIB with component polymer proved that its processability can be further explored for optimal spinnability of nanofibers for desired applications.


Author(s):  
Yunshen Cai ◽  
Michael Gevelber

Electrospinning produces submicron fibers for a variety of applications using a wide range of polymers. Achieving the desired fiber diameter, maximizing productivity, and minimizing variation are important production objectives. This paper addresses several important areas needed to develop a general electrospinning control approach including: developing a correlation between measurements, process conditions, and the resulting fiber diameter, developing a method to determine an operating regime that meets manufacturing objectives, and identifying process dynamics for controller design.


NANO ◽  
2019 ◽  
Vol 14 (11) ◽  
pp. 1950139
Author(s):  
Saleh S. Abdelhady ◽  
Said H. Zoalfakar ◽  
M. A. Agwa ◽  
Ashraf A. Ali

This study is an attempt to optimize the electrospinning process to produce minimum Nylon 6,6 nanofibers by using Taguchi statistical technique. Nylon 6,6 solutions were prepared in a mixture of formic acid (FA) and Dichloromethane (DCM). Design of experiment by using Taguchi statistical technique was applied to determine the most important processing parameters influence on average fiber diameter of Nylon 6,6 nanofiber produced by electrospinning process. The effects of solvent/nylon and FA/DCM ratio on average fiber diameter were investigated. Optimal electrospinning conditions were determined by using the signal-to-noise (S/N) ratio that was calculated from the electrospun Nylon 6,6 nanofibers diameters according to “the-smaller-the-better” approach. The optimum Nylon 6,6 concentration (NY%) and FA/DCM ratio were determined. The morphology of electrospun nanofibers is significantly altered by FA/DCM solvent ratio as well as Nylon 6,6 concentration. The smallest diameter and the narrowest diameter distribution of Nylon 6,6 nanofibers ([Formula: see text][Formula: see text]nm) were obtained for 10 wt% Nylon 6,6 solution in 80 wt% FA and 20 wt% DCM. An increase of 118%, 280% and 26% in tensile strength, modulus of elasticity and elongation at break over as-cast was obtained, respectively. Glass transition temperature of Nylon 6,6 nanofibers were determined by using differential scanning calorimeter (DSC). Analysis of variance ANOVA shows that NY% is the most influential parameter.


2021 ◽  
pp. 004051752110666
Author(s):  
Peng Chen ◽  
Qihong Zhou ◽  
Jun Wang ◽  
Ge Chen

Electrospinning is an efficient and straightforward method for producing thin fibers from various materials. Although such thin fibers have diverse potential applications, the remaining problems with electrospinning are the whipping instability (also known as bending instability) of electrically charged liquid jets of polymer nanofibers and uneven fiber diameter distribution. In this study, we report a novel magnetic lens electrospinning system and discuss the principle of reducing the fiber diameter and width of the whipping circle in this electrospinning process. The effects of three types of electrospinning devices, needle-to-plate, needle-exciting coil-to-plate, and needle-magnetic lens-to-plate types, were studied through numerical simulation to analyze the electrospinning fiber collection state. For the 12 wt% polyacrylonitrile solution, when the applied voltage was 14–20 kV, the feed rate was 0.4–0.7 ml/h, and the current applied to the excitation coil or magnetic lens was 1 A, the experimental results demonstrated that, compared with needle-to-plate-type and needle-exciting coil-to-plate-type electrospinning, needle-magnetic lens-to-plate-type electrospinning produced smaller whipping circles with thinner and more uniform fibers.


Sign in / Sign up

Export Citation Format

Share Document