Electrospinning of cellulose acetate nanofiber membrane using methyl ethyl ketone and N, N-Dimethylacetamide as solvents

doi:10.1016/j.matchemphys.2019.122147

Materials Chemistry and Physics

Volume 240, 15 January 2020, 122147

https://doi.org/10.1016/j.matchemphys.2019.122147 Get rights and content

Highlights

•
Cellulose acetate nanofibers electrospun using high boiling point solvent mixture of MEK and DMAc.
•
Formation of cylindrical and beaded CA nanofibers mapped vs. solvent ratios and polymer concentration.
•
Sessile drop experiments proved hydrophilic nature & good wettability.
•
Membranes had DI water flux of 10,197.044 Lm⁻²h⁻¹ for initial 50 ml.
•
Membranes could be reused four times without rupture and suitable for water filtration application.

Abstract

Cellulose acetate (CA) nanofiber membrane was prepared by electrospinning method using solvent mixtures of methyl ethyl ketone (MEK) and N, N, - dimethylacetamide (DMAc) in different ratios (2:1, 1:1, 1:2) and also different concentration of CA (7–19%). MEK was selected in place of acetone due to its high boiling point, thereby, minimises the evaporation loss of the solvent enabling the longer duration of electrospinning. The morphology of electrospun nanofibers was observed by Scanning Electron Microscope (SEM). It was observed that cylindrical fibers formed at higher concentration of polymer with increase of DMAc. Fiber diameters were in the range of 40–500 nm with large diameters formed at higher polymer concentration. Contact angle measurement revealed that membranes have good wetting property. The water flux measurements of membranes were carried out under gravity. A water flux of 10,197 Lm⁻²h⁻¹ was measured initially and was reduced subsequently to 365-200 Lm⁻²h⁻¹. The membranes could be reused up to four times without rupture. The above experiments suggest that MEK and DMAc could be an alternate solvent system in addition to other systems.

Graphical abstract

Introduction

Cellulose Acetate (CA) is a cheap, naturally degradable polymer with glass transition temperature of 190 °C, therefore, suitable for membrane applications involving low to medium temperature fluids [[1], [2], [3]]. Due to its good hydrophilic property, non-toxicity, chemical and thermal stability, moderate mechanical properties, low cost etc. [3,4], CA is an excellent material for water filter membranes. As an example, N. Chitpong, & S. M. Husson [5] used electrospun cellulose acetate nanofiber membranes for removal of cadmium. Similarly, inclusion of CA nanofibers in cigarette filter tip increased the efficiency of tar removal from 47.7% to 71.6% [6].

Cellulose acetate has been widely used as membranes for wound dressing [4], reverse osmosis [7], dialysis [8], ultra-filtration [9] etc. Electrospinning is a suitable process to obtain high aspect ratio nanofibers even at industrial scale [10]. Numerous polymeric, as well as ceramic fibers, have been produced by using electrospinning process [[10], [11], [12], [13]]. Generally, the process involves the application of high voltage to a polymer droplet making it to eject a thin jet. A syringe used to carry and push the solution to be electrospun at uniform rate. The syringe needle acts as an electrode and metallic stand warped with aluminium foil that is grounded acts as counter electrode. The jet is emitted when externally applied electrical field crosses a critical value [14] and jet subdivides into micro to nanofibers as it travels towards metallic collector due to forces between similar charges in polymer jet.

Many researchers studied electrospun cellulose acetate nanofibers using different solvent systems [[15], [16], [17], [18], [19]]. The various solvents used for electrospinning were: acetone, DMAc, DMF, TFE, chloroform, methanol, water or their mixtures in various ratios, acetone been the common solvent. Since, the boiling point (56 °C) of acetone is low, it evaporates quickly making difficult in electrospinning for longer duration required large scale production of membranes for various applications. It was felt that an alternate solvent system with a high boiling point solvent in place of acetone is necessary.

Therefore, methyl ethyl ketone having boiling point of 80 °C was considered along with DMAc in this study. The electrospinning was carried out at different MEK: DMAc ratios as well as at different polymer concentration. The morphology of nanofibers (beads and cylindrical) obtained at different conditions was correlated/mapped w.r.t. the solvent ratios and concentration of polymer. In addition, water flux studies under gravity of the membranes and their reusability were also studied.

Section snippets

Materials

Cellulose Acetate (CA) (acetyl group 29–45%) white powder, Methyl Ethyl Ketone (MEK) and N, N-Dimethylacetamide (DMAc) solvents were procured from Loba Chemie, India. The properties of solvents are given in Table 1 [20].

Preparation of homogeneous viscous CA solution

To study the effect of single solvent, CA solutions in MEK were prepared at 8 and 10% (w/v) and solutions of CA in DMAc were prepared at 10 and 15% (w/v) on a magnetic stirrer (IKA C-MAG HS4) at 500–750 rpm. Also, to study the effect of the mixed solvent system, three different

Single solvent system

Solutions of CA (10 & 20%) in DMAc were clear and viscous enough for electrospinning and produced only particles/beads, but not the fibers. Liu and Heish [15], and Tungaprapa et al. [18] also reported the inability to produce fibers in single solvent of DMAc. Similarly, it was difficult to prepare fibers of cellulose acetate using MEK solvent. In the former case, dielectric constant and surface tensions are too high while in the latter case, they are too low [Table .1]. Therefore, it was felt

Conclusions

In this paper, cellulose acetate nanofibers were obtained by electrospinning CA solutions in MEK and DMAc solvent mixtures. It was found that MEK rich solvent produce cylindrical fibers at low polymer concentration. DSC study revealed glass transition temperature (T_g) and melting temperature (T_m) of the electrospun nanofibers to be around 186 °C and 226 °C respectively. Contact angle measurements proved the membrane is hydrophilic with good wettability. Water flux studies on cellulose acetate

Acknowledgements

The authors gratefully acknowledge Department of Science and Technology (DST), New Delhi for providing financial grants (DST/TM/WTI/2k14/205(G)/2) to carry out the research work. The authors are thankful to Ms Kalavati, Mr.Srinivasa and Mr. Krishna for their help in obtaining SEM images, FTIR and DSC scans respectively. Thanks to Dr Lakshmi R.V, Surface Engineering Division for her help in sissile drop experiments.

References (28)

N. Chitpong et al.
Polyacid functionalized cellulose nanofiber membranes for removal of heavy metals from impaired waters
J. Membr. Sci.
(2017)
A. Idris et al.
The effect of different molecular weight PEG additives on cellulose acetate asymmetric dialysis membrane performance
J. Membr. Sci.
(2006)
Z.M. Huang et al.
A review on polymer nanofibers by electrospinning and their applications in nanocomposites
Compos. Sci. Technol.
(2003)
Z. Ma et al.
Electrospun cellulose nanofiber as affinity membrane
J. Membr. Sci.
(2005)
C. Zhang et al.
Study on morphology of electrospun poly(vinyl alcohol) mats
Eur. Polym. J.
(2005)
H. Fong et al.
Beaded nanofibers formed during electrospinning
Polymer
(1999)
H. Steinmeier
Acetate manufacturing, process and technology
Macromol. Symp.
(2004)
J. Puls et al.
Degradation of cellulose acetate-based materials: a review
J. Polym. Environ.
(2011)
G. Wypych
Handbook of Polymers
(2016)
N. Sultana et al.
Cellulose acetate electrospun nanofibrous membrane: fabrication, characterization, drug loading and antibacterial properties
Bull. Mater. Sci.
(2016)

Y. Molaeipour et al.

Filtration performance of cigarette filter tip containing electrospun nanofibrous filter

J. Ind. Text.

(2015)

J. Kopecek et al.

Structure of porous cellulose acetate membranes and a method for improving their performance in reverse osmosis

J. Appl. Polym. Sci.

(1969)

O. Kutowy et al.

Cellulose acetate ultrafiltration membranes

J. Appl. Polym. Sci.

(1975)

P.K. Panda et al.

Synthesis and applications of electrospun nanofibers- a review

Cited by (29)

Incorporation of zwitterionic carbon quantum dots in cellulose acetate tubular membrane for oil/water separation
2024, Separation and Purification Technology
The substantial generation of oily industrial wastewater poses a considerable environmental threat. A promising strategy for addressing this challenge involves employing ultrafiltration membranes integrated with a hydrophilic nanomaterial. This study aims to investigate the properties of zwitterionic carbon quantum dots (ZQDs) and enhance the performance of cellulose acetate (CA) tubular membranes by incorporating ZQDs. The CA tubular membrane was crafted using the dry-wet spinning method. The introduction of ZQDs into the CA casting solution disrupted its thermodynamic stability and expedited the non-solvent inflow rate during membrane formation, thereby augmenting both membrane porosity and pore size. The inclusion of ZQDs heightened the membrane's hydrophilicity owing to the presence of hydrophilic functional groups in the nanomaterial. The modified tubular membrane demonstrated high pure water and diesel oil-water emulsion permeate flux of 581.3 ± 33.9 L m⁻¹ h⁻¹ bar⁻¹ and 350.5 ± 11.2 L m⁻¹ h⁻¹ bar⁻¹, respectively, with an impressive oil rejection rate of 98 %. The flux recovery and reversible fouling ratio increased to 88.42 % and 28.12 %, respectively, while the irreversible fouling ratio decreased to 11.57 %. The modified tubular membrane effectively rejected various oil-water emulsions (diesel oil, dodecane, canola oil, and engine oil) with a separation efficiency ranging from 94 % to 99 %. In conclusion, the zwitterionic-modified tubular membrane proved to be effective in the separation of oil and water.
Electrospun nanofibers for photocatalytic water treatment and hydrogen generation application: A review
2023, International Journal of Hydrogen Energy
Clean and green energy are frontline research areas today worldwide to substitute the fossil based fuel to minimize greenhouse effect. Hydrogen is one of the prominent clean and green energy alternate to fossil fuels. It is a high calorific, carbon free renewable energy. Hydrogen is abundantly available on earth in combined form such as water, hydrocarbons, natural gases etc. Efficient generation of hydrogen from these sources without making pollution is an utmost priority. Photocatalytic hydrogen generation by splitting water using sunlight is one of the recent research areas of interest due to abundant availability of solar energy. Advanced research on photocatalytic materials is needed to accelerate H₂ generation using solar energy. Among various forms of photocatalytic materials, nanofiber based metal/metal oxide semiconducting materials owing to their unique physio-chemical properties show great potential for splitting of water over other nanostructured materials. In this review article, various nanostructure semiconducting materials used for photocatalytic water splitting are presented with a special emphasis on electrospun nanofibers. Various factors affecting the photocatalytic conversion efficiency, modification and performance enhancement strategies of various types of nanofibers (oxides and non-oxides) for generation of hydrogen from water is presented. Comparison of photocatalytic and photo-electrochemical processes for water treatment are also discussed. Novelty of the paper lies on advantages of nanofibrous materials over traditional nano particles for photocatalytic H₂ generation. Also, the challenges and future prospectus of electrospun nanofiber based photocatalytic materials towards hydrogen generation are discussed.
Development and characterization of a polydimethylsiloxane-cellulose acetate hybrid membrane for application in organ-on-a-chip
2023, Materials Science and Engineering: B
Membranes are barriers connecting dissimilar environments, thus, hold an important place in the human body. Therefore, studying the membranes is critical for understanding the body's functions with respect to cell/tissue/organ and its surrounding. In vitro cell cultures (2D and 3D) can utilize the membrane properties like compartmentalization, transport of ions, gases, and signaling molecules. We have developed a strong yet elastic membrane which allows the cell growth over its surface. The membrane, a composite of PDMS (elastomer) and cellulose acetate (biopolymer), is characterized morphologically, physically, chemically, and biologically. A biocompatible, elastic, gas permeable, and liquid impermeable membrane is developed. To conclude, the membrane with one-part PDMS, eight-parts toluene, and two-parts cellulose acetate is ideal for cell growth and would be used in applications such as lung-on-a-chip to mimic the lung-alveolar interface allowing cell growth on either sides of the membrane.
.
The enhanced photocatalytic performance of the amorphous carbon/MgO nanofibers: Insight into the role of the oxygen vacancies and 1D morphology
2023, Applied Surface Science
High performance, recycling easily, green, and cheap are necessary for the practical application of photocatalysts. Here, a novel composite of amorphous carbon and magnesium oxide nanofibers (C/MgO-F-600) is fabricated by an electrospinning method. Instead of organic solvents, H₂O is employed as the electrospinning solvent, which is environmentally friendly. The degradation efficiency of C/MgO-F-600 to methylene blue (MB) is 91.51%, which is about 1.9 times higher than that of MgO-600 nanosheets. The enhanced photocatalytic activity of the C/MgO-F-600 is mainly ascribed to the moderate content of oxygen vacancies and 1D nanofiber structure, resulting in the higher photocurrent density, photocatalytic activity and the lowest bandgap and impedance. This work provides the feasibility for the improvement of wide bandgap photocatalysts (MgO) in practical applications.
Electrospinning of poly(ε-caprolactone) (PCL) and poly ethylene glycol (PEG) composite nanofiber membranes using methyl ethyl ketone (MEK) and N N’-dimethyl acetamide (DMAc) solvent mixture for anti-adhesion applications
2022, Materials Today Communications
Citation Excerpt :
In our laboratory, methyl ethyl ketone (MEK) and N N’-dimethyl acetamide (DMAc) solvent mixture was used for electrospinning cellulose acetate. This solvent mixture could provide nanofibers with smooth morphology and electrospinning continued for longer duration without any interruption which was attributed to reduced rate of solvent evaporation [33]. There is no literature to the best of our knowledge reporting use of MEK and DMAc as a solvent mixture for electrospinning of PCL/PEG and their use as anti-adhesive membranes.
Anti-adhesion membranes are very essential barrier materials to be placed at the injured site for preventing adhesions. Electrospun biocompatible polymer nanofiber membranes are of interest for anti-adhesion applications due to their nano porous structure and high surface area. In this study, PCL-PEG based composite fibre-particle hybrid membranes were fabricated for preventing the proliferation of fibroblasts. PCL/PEG composite nanofibers with varying PEG content (10 – 30 wt%) were prepared by electrospinning technique and evaluated for their thermal and physio-chemical properties. Thermogravimetric Analysis (TGA) revealed PCL / PEG composite membranes thermally stabile up to 300 °C. The improved surface wettability of PCL/PEG (80/20) composite nanofibers allowed ease of functionalization with PEG and chitosan. SEM and FTIR studies showed the existence of chitosan on the surface of nanofibers. In vitro degradation studies confirmed the controlled degradation of all the membranes. Cell culture studies showed that all the nanofiber membranes are biocompatible and functionalized nanofibers reduced the adhesion and proliferation of L929 fibroblasts cells. It was observed that the surface functionalized composite nanofibers could serve as a substitute to the existing anti-adhesion membranes.
Poly(dimethyl siloxane) anti-corrosion coating with wide pH-responsive and self-healing performance based on core−shell nanofiber containers
2022, Journal of Materials Science and Technology
Citation Excerpt :
The peaks at 2943 and 2885 cm−1 are due to the methylene (-CH) bonding in CA, while the symmetric and asymmetric bending peaks of methylene (-CH) can be observed at 1368 and 1431 cm−1, respectively. The absorption vibration peaks at 1223 and 1040 cm−1 are assigned to the ester groups (C-O-C), which are the ligands between the main chains of CA [36]. As Fig. 4(a) shows, the characteristic peaks of OA are detected at 1288, 1705, and 1458 cm−1, which are attributed to COOH, the carbonyl peak of CA, and the asymmetric -CH3 bonding, respectively.
In this research, core−shell electrospun fibers loaded with the shell of cellulose acetate and the core of oleic acid and alkyd varnish resin were synthesized and used within poly(dimethyl siloxane) (PDMS) to prepare self-healing and pH-responsive coatings for a steel substrate. The morphology of the electrospun fibers was characterized by scanning electron microscopy, transmission electron microscopy and confocal fluorescence microscopy. Thermo gravimetric analysis and Fourier transform infrared spectroscopy revealed that the self-healing agents were loaded successfully with a loading rate of 2.9%. The properties of the fiber-PDMS composite coating were characterized by water contact angle measurements, mechanical tests, electrochemical impedance spectroscopy, and scanning Kelvin probe. Results show that the maximum self-healing efficiencies of the fiber-PDMS coating in alkaline and acidic solution are 95.96% and 97.04%, respectively. The composition of the self-healing agents at the damaged part of the coating was verified by an infrared mapping test and using an energy dispersive spectrometer. In addition, the sandpaper abrasion test shows the hydrophobic effect of fiber-PDMS coating remains above 88.2% and decreases slightly through the addition of abrasion cycles. This research can pave the way for the industrial applications of pH-responsive self-healing coatings.

View all citing articles on Scopus

View full text

Electrospinning of cellulose acetate nanofiber membrane using methyl ethyl ketone and N, N-Dimethylacetamide as solvents

Highlights

Abstract

Graphical abstract

Introduction

Section snippets

Materials

Preparation of homogeneous viscous CA solution

Single solvent system

Conclusions

Acknowledgements

J. Membr. Sci.

J. Membr. Sci.

Compos. Sci. Technol.

J. Membr. Sci.

Eur. Polym. J.

Polymer

Acetate manufacturing, process and technology

Macromol. Symp.

Degradation of cellulose acetate-based materials: a review

J. Polym. Environ.

Handbook of Polymers

Cellulose acetate electrospun nanofibrous membrane: fabrication, characterization, drug loading and antibacterial properties

Bull. Mater. Sci.

Filtration performance of cigarette filter tip containing electrospun nanofibrous filter

J. Ind. Text.

Structure of porous cellulose acetate membranes and a method for improving their performance in reverse osmosis

J. Appl. Polym. Sci.

Cellulose acetate ultrafiltration membranes

J. Appl. Polym. Sci.

Synthesis and applications of electrospun nanofibers- a review