| Parameter |
Material |
Methods and Preparations |
Results |
Findings |
Citation |
|
Cellulose |
-
●
Dissolving Cellulose (0.628 g) in [C2min] [OAc], IL (5 g).
-
●
Adding different amounts of DMF or DMAc (5, 3.75, 2.5 g) with concentrations of (6.3, 7.2, 8.3%) (w%) Respectively.
-
●
Rotating wired cylinder collector.
-
●
Applied voltage 30 kV.
-
●
TCD 150 mm.
-
●
Immersing the spun fiber in Ethanol at 4 °C, 2 h.
Drying fiber at 50 °C, 1 day. |
-
●
Average fiber diameter for different concentration of the co-solvent is about: (500, 410 and 380 nm) for DMF & (1080, 760 and 620 nm) for DMAc, respectively.
-
●
Degree of crystallinity for different concentration is (0.67, 0.71 and 0.71) for DMF and (0.61, 0.68 and 0.7) for DMAc, respectively.
|
|
[26] |
| Concentration, Viscosity and Type of Solvent |
(E-CE)C |
-
●
(E-CE)C with Mn of 9.7 × 104 g/mol was prepared by a reaction of EC and Acrylonitrile with a DS of 2.1 for Ethyl and 0.37 for Cyanoethyl.
-
●
THF was used as the solvent.
-
●
(E-CE)C/THF solution concentrations of (16, 17, 18 and 19) wt% were applied.
-
●
Applied voltage 30 kV.
-
●
The diameter of orifice was 1.2 mm.
-
●
TCD was 150 mm.
|
-
●
Fiber will be formed only between the concentration of [15–22%], outside this range no formation for the fiber.
-
●
the average fiber diameter was (2200, 2000, 2900 and 3200) nm, with (16, 17, 18 and 19) wt% (E-CE)C/THF solution concentrations respectively.
|
|
[27] |
|
(CMC) & (PEO) |
-
●
(PEO) with a Mw of 400000 g/mol is used in a mixture with (CMC).
-
●
Different types of CMC were used with different MW and DS as follow: CMC Cekol 30 (A), CMC Cekol 700 (B).
-
●
CMC Cekol 2000S (C), CMC Cekol 500T (D) with Mw of 120, 280, 350, 250 (g/mol) and with DS 0.72, 0.77, 1.24, 0.72 respectively
-
●
PEO and CMC are mixed at a ratio of 1:1 then they are dissolved in water.
-
●
TCD was set to 200 mm.
-
●
Constant voltage at 35 kV.
|
-
●
At a concentration of 8% for all CMC derivatives, the fibers are straight with an even diameter, the mean diameter of the individual fibers lies between 200 and 250 nm.
-
●
CMC (D) couldn’t be electro-spun at 8% conc. due to its high viscosity, so a lower conc. than 6% was used.
-
●
CMC (A) & (B) lead to the formation of homogenous fibers.
-
●
CMC (C) required a slightly higher voltage (40 kV) due to its high viscosity.
-
●
Nonwoven sheets and individual nanofibers were formed.
|
|
[28] |
|
Chitosan & PVA |
-
●
Chitosan 10 of Mv = 2.1 × 105; degree of deacetylation, 0.78 and PVA (Degree of polymerization, approximately 2000; Mn = 8.8 × 104) are used.
-
●
The solvent is a mixture of FA and DW.
-
●
A solution of PVA-DW (9 wt %) was mixed with a chitiosan10-FA solution (7 wt%) with volume ratios 90:10, 70:30, 50:50, and 30:70, respectively.
-
●
Experiment was performed at room temperature.
-
●
A 3 mL syringe with a capillary tip having an inner diameter of 0.6 mm.
-
●
Applied voltage was 15 kV.
-
●
TCD was 150 mm.
|
-
●
At a ratio of 100:0 chitosan to PVA, no jet had been obtained.
-
●
At a ratio of 90:10 beads started to appear on the collector.
-
●
At a ratio of 70:30 the size of the beads becomes smaller and thin fibers started to appear among these beads.
-
●
For a ratio of 50:50 homogeneous fibers with 120 nm average diameter started to appear.
-
●
For a ratio of 30:70, the fiber was thicker (with an average diameter of 170 nm).
-
●
At 0:100 chitosan to PVA, Average fiber diameter was 470 nm.
|
|
[29] |
|
Chitosan |
-
●
Chitosan with ≥75% degree of d-acetylation, was used.
-
●
The solvent used was TFA/DCM with different volume ratios.
-
●
The solution was kept under massive and constant magnetic stirring until all the chitosan was dissolved.
-
●
The chitosan concentration was 7% (w/v).
-
●
Diameter of the orifice was 0.5 mm.
-
●
Applied voltage was 25 kV.
-
●
TCD was 150 mm.
-
●
feed rate of 2 mL/h.
|
-
●
For 60:40, 70:30, 80:20 vol ratio of TFA:DCM the average fiber diameter was 360, 410, 490 nm.
|
|
[30] |
|
Chitosan & PVA |
-
●
4% (w/v) Chitosan flakes were dissolved in 2% (w/v) acetic acid.
-
●
PVA powder was dissolved in deionized water at 90 °C for 2 h.
-
●
The two solutions were mixed.
-
●
Voltage was 15 kV.
-
●
TCD was 150 mm.
-
●
Feed rate was 0.03 mL/h.
-
●
Temperature was 20 °C
-
●
Humidity was 51%.
|
-
●
For different PVA: Chitosan ratios (100:0, 95:5, 90:10, 80:20, 75:25, 70:30, 50:50) (w:w) the average fiber diameter was 1059, 823.6, 799.4, 637.6, 393.6, 286.2, 119.8 nm.
-
●
When the Chitosan content was more than 50%, the electrospinning process couldn’t occur.
|
-
●
The increase of the chitosan content leads to the increase of the charge density, which hardens the process of fiber formation.
-
●
The smallest fibers can be obtained with the increasing of chitosan content.
|
[31] |
|
Chitosan |
-
●
Three samples of Chitosan were used with the following Mw (30,000, 106,000, 398,000 g/mol) with degree of deacetylation of (56%, 54%, 65%) respectively
-
●
The solution was inserted into a syringe with an orifice diameter of 0.58 mm.
-
●
The flow rate was adjusted to be 1.2 mL/h.
-
●
voltage up to 40 kV.
|
-
●
At acetic acid concentration of 30% (wt%) Average diameter was found to be 40 nm with large beads. But, at concentration of 90% (wt%) the fiber diameter increased to 130 nm without beads.
-
●
As the concentration of acetic acid increased from 10 to 90% (wt%), Surface Tension decreased from 54.6 to 31.5 dyn/cm
|
-
●
The known difficulty in electrospinning of Chitosan can be solved by dissolving Chitosan in concentrate acetic acid in water, resulting in low surface tension.
-
●
Acetic acid concentration was the most important parameter as it decreased surface tension and increased charge density without significant effect on viscosity.
|
[32] |
|
CA |
-
●
Cellulose acetate with 39.8% acetyl content and Mw of 30,000.
-
●
Acetic acid and water were mixed to make the solvent.
-
●
Cellulose Acetate of 17 wt% was dissolved in acetic acid solution of concentration higher than 70 wt%.
-
●
The applied voltage was 25 kV.
-
●
TCD was adjusted to 100 mm.
-
●
The flow rate was set to 3 mL/h.
-
●
The orifice diameter was 0.84 mm.
|
-
●
The viscosity of CA solutions increased by the increase of acetic acid up to 80 wt%, and then it decreased.
-
●
The conductivity decreased by the increase of the water content.
-
●
The average fiber diameter was as follow (200, 250, 300, 500, 1300 nm) for acetic acid concentration of (70, 75, 80, 90, 95 wt %)
|
|
[33] |
|
Cellulose |
-
●
Raw cellulose fiber was used.
-
●
The cellulose fiber was dried at 105 °C for 24 h
-
●
Cellulose was dissolved in IL of BMIMAc ≥95% in concentration, (300 mg of cellulose was added to 29.7 g IL).
-
●
Stirred for 72 h at 90 °C and 250 rpm
-
●
The solution was loaded in 10 mL syringe of 0.337 mm needle inner diameter.
-
●
TCD was adjusted to be 25 mm.
-
●
The applied voltage varied from 6 to 12 kV
-
●
Flow rate was 1.36 and 2.38 mL/h
-
●
Temperature inside the syringe was (110 ± 10)
-
●
The process was done at constant relative humidity (65 ± 3%) and temperature of (21 ± 1 °C).
|
-
●
Stable fiber formed at 2 and 3 wt% concentration
-
●
In case of 1 wt% concentration the Taylor cone was interrupted with the existence of solution droplets.
-
●
In case of 4 wt% concentration the viscosity of the solution was too high which prevent the formation of fibers.
|
|
[34] |
|
CA & CB |
-
●
12% (w/v) Cellulose acetate of 29–46% acetyl content was dissolved in DMAA with ratio of 4:1 (v/v).
-
●
The CA/DMAA solution was mixed with PEG for 1:1 (w/w)
-
●
CB of (0.7, 1.5 and 2.2 wt%) was mixed with the CA solution
-
●
20 mL syringe was used
-
●
The applied voltage was 26 kV and −10 Kv.
-
●
The process was done at 24 °C and relative humidity lower than 20%.
-
●
TCD was 10 cm
-
●
Flow rate was 10 mL/h
-
●
The aluminum collector was on cylindrical shape.
|
-
●
Cylindrical bead free smooth fibers were formed with the following characteristics:
-
-
The average fiber diameter was 495, 628, 727, and 831 nm for 0.7, 1.5 and 2.2 wt% of CB respectively.
-
-
A few CB small particles were adhered to the resulted fibers.
-
-
Pores formed on the surface of the resulted fibers.
|
|
[35] |
|
Chitosan |
-
●
Two solutions were used in the experiment chitosan – TFA and chitosan – TFA/DCM
-
●
The first solution was made by mixing 1.12 g of chitosan with 14.9 g of TFA and the final solution concentration was 7 wt%.
-
●
The second solution was made by mixing 1.09 g of chitosan with 10.43 g of TFA dissolved in 3.99 g of DCM at a ratio of 70:30 (TFA: DCM) (v/v), the final solution concentration was 7 wt%
-
●
The two solutions were prepared at room temperature
-
●
The two solutions were left for a night to make a homogeneous solution
-
●
20 mL syringe was used
-
●
Flow rate was 0.08 mL/h and 0.1 mL/h for the two solutions respectively
-
●
25 kV was applied
-
●
TCD was 12 cm and 14 cm for the two solutions respectively
-
●
Aluminum collector was used
|
-
●
Electrospinning of the first solution yields fiber with an average diameter of 95.58 ± 39.28 nm and beads formation was observed in it.
-
●
Electrospinning of the second solution yields bead-free fiber with an average diameter of 907.94 ± 290.18 nm
|
|
[36] |
|
(PLA/CMC/GO-f-COOH) |
-
●
10 mL of the polymer matrix solution PLA, CMC/GO-COOH, PCGC a syringe with an orifice stainless-steel needle with a diameter of 0.6 mm
-
●
Voltage was 20 kV,
-
●
Flow rate of 0.25 mL/h.
-
●
The distance between the needle and the collector was 20 cm,
|
|
-
●
The increase of thermal treatment result in an increasing in the surface area of the planar surface
-
●
High difference in the morphologies of nanofibrous membranes could clearly be seen,
-
●
The fiber diameters were different for all the nanofibrous materials.
-
●
The nanofibrous membrane had a good distributed pore size, and the PLA sample was densely fibrous more than the other samples.
|
[37] |
|
Chitosan & PEO |
-
●
Chitosan (5% w/v) and PEO (2.5% w/v) solutions in 70% v/v acetic acid were mixed to obtain different Chitosan:PEO respective weight ratios of 9:1, 8:2, 7:3, 6:4, and 5:5.
-
●
A pure Chitosan solution (5% w/v) was tried to obtain electrospinning nanofibers.
-
●
5 mL syringe with a needle (gauge 20).
-
●
The flow rate was 0.3 mL/h
-
●
The distance between the collector and the needle tip was 15 cm.
-
●
Voltage range of 25–28 kV
|
-
●
Nanofibers based on 8:2 Chitosan:PEO exhibited the smallest diameter (119.17 ± 22.05 nm) and the greatest mucoadhesion (22.82 ± 3.21 g/cm2)
-
●
A spinnable solution containing Chitosan and PEO at a respective weight ratio of 9:1 produced nanofibers with an average diameter of 135.54 ± 67.48 nm
|
-
●
The high viscosity of the pure Chitosan solution is owing to the strong hydrogen bonding between its OH and NH2 groups.
-
●
PEO molecules linked to chitosan backbone could disrupt chitosan chain self-association and reduce chitosan solution viscosity
-
●
Small and flexible PEO chains can also lie down along the rigid chitosan macromolecules smoothing their flow.
|
[38] |
|
Chitosan & PEO |
-
●
Low molecular weight chitosan with a viscosity average molecular mass = 540 kDa and a degree of deacetylation DD = 78%
-
●
Chitosan powder was dissolved using a 5% v/v acetic acid water solution to obtain a polymer concentration of 2.5%, 3.0% and 3.5% wt
-
●
PEO powder was added in a Chitosan/PEO mass ratio of 50/50 to obtain a final polymer concentration of 5%, 6% and 7 % wt.
-
●
A solution flow rate of 0.15 mL/h
-
●
A voltage of 17.5 kV
-
●
A needle-flat collector distance of 20 cm.
|
-
●
The sample obtained by Chitosan:PEO of 50:50, 5 % wt solution with a diameter ranging from 500 nm up to 2 μm and connecting the nanofibers, by an average dimension of 150 ± 30 nm.
-
●
The other two samples are both characterized by a similar structure with homogenous and smooth nanofibers of around 300 ± 30 nm
-
●
However, the mat obtained by Chitosan:PEO of 50:50 6 % wt formulation presents a high number of defects (e.g. beads, collapsed structures, low fibre density regions), whereas the one obtained by Chitosan:PEO of 50:50, 7 % wt. formulation shows the best structure in terms of fiber homogeneity.
|
-
●
The spinnability increased with solution viscosity, as well as the improvement of homogeneity and overall morphology of nanofibers.
-
●
Decrease of the viscosity as the shear rate increases due to the progressive orientation and disentangle of the chains
-
●
The increase of viscosity of the spinning solution often leads to the increase of polymer concentration, so that the fiber diameter increases and the bead like structure disappear.
|
[39] |
| Surface Tension |
(E-CE)C |
-
●
(E-CE)C with Mn weight of 9.7 × 104 g/mol, was prepared by a reaction of EC and Acrylonitrile with a DS of 2.1 for Ethyl and 0.37 for Cyanoethyl.
-
●
THF was used as the solvent.
-
●
The applied voltage is 30 kV.
-
●
The diameter of orifice was 1.2 mm.
-
●
TCD was adjusted to be 150 mm.
|
-
●
When the concentration of the (E-CE)C/THF solutions was lower than 15 wt%, the fibers could not be formed by electrospinning because of the low surface tension and viscosity.
-
●
At solution concentrations greater than 22 wt%, the solution jet could not erupt because of the high surface tension and viscosity.
|
-
●
Surface tension is observed to be increased by increasing the respective concentration.
-
●
By increasing surface tension, average diameter of the fibers increases and the diameter distribution becomes wider with increasing the concentration.
|
[27] |
|
H-Chitosan |
-
●
H-chitosan was prepared by a heterogeneous acylation reaction between Chitosan and hexanoyl Chloride.
-
●
H-chitosan in chloroform to produce a solution of concentration between (4–14%) (w/v)
-
●
Voltage ranged from 12 kV.
-
●
Needle was tilted at 45°.
-
●
TCD was 120 mm.
|
-
●
When the conc. of H-chitosan was 4% (w/v), the conductivity was 0.25 mS/cm only beads formed at this concentration.
-
●
At 6% conc. The conductivity was 0.27 mS/cm, and the average fiber diameter was 640 ± 360 nm.
-
●
At 8%, the conductivity was 0.28 mS/cm, and the average fiber diameter was 1230 ± 670 nm.
-
●
At 10%, conductivity was 0.35 mS/cm, and the average fiber dimeter was 1490 ± 690 nm.
-
●
At 14%, the conductivity was 0.4 mS/cm, and the average fiber diameter was 3930 ± 1820 nm.
|
-
●
Conductivity of the solution increases with the increase of the H-chitosan concentration, which happens as a reason of increasing the hydroxyl group in the solution.
-
●
The average diameter increased with the increasing of the conductivity of the solution
|
[40] |
|
Conductivity
Chitosan & PEO
|
-
●
Chitosan and PEO solutions with 2–8% concentration was dissolved in acetic acid aqueous of 2 wt%.
-
●
Mass ratios of Chitosan:PEO were 1:1, 2:1 and 5:1.
-
●
Chitosan solutions with concentrations 1 wt% to 6 wt% and PEO solutions with 1 wt% to 3 wt% in aqueous 2 wt% acetic acid
-
●
stirred overnight at room temperature.
-
●
a 50 mL syringe with a metal capillary.
-
●
The applied voltage was set to be 15 kV.
-
●
The flowrate was adjusted to 0.1 mL/h.
-
●
TCD was adjusted to be 200 mm.
|
-
●
Conductivity of Chitosan was found to be 2.6–9.6 mS/cm, and conductivity of PEO was found to be 0.85–1.22 S/cm.
-
●
● With the increase of Chitosan concentration, Conductivity of Chitosan solutions significantly increased. The viscosity also increased at concentrations of 1–6 wt%.
-
●
With the increase of PEO concentration, the conductivity of Chitosan/PEO solutions decreased.
-
●
With the increase of PEO concentrations, Surface Tension of PEO solutions reduced. Fibers were produced with an average diameter of 124 nm at 6 wt% solutions (1:1) (w/w).
|
|
[41] |
