Influence of volatile solvents and mixing ratios of binary solvent systems on morphology and performance of electrospun poly(vinylidene fluoride) nanofibers

Electrospinning process was used to fabricate electrospun poly(vinylidene fluoride) (PVDF) nanofibers using binary solvent systems of N,N-dimethylformamide (DMF) and 10 other volatile solvents, namely acetone, tetrahydrofuran, methyl acetate (MA), ethyl acetate (EA), propyl acetate, butyl acetate, ethanol, methanol, chloroform and hexane. The nanofibrous film was investigated and it was noted that the formation of resultant PVDF nanofibers was improved depending on an increase of the amount of the volatile solvent in the PVDF solution. The average diameters of the fibers in the electrospun films were 174-1150 nm. A large amount of volatile solvent was responsible for low dark spot and bead-free morphological observation. The mechanical properties of the fibers were strongly influenced by the morphology, uniformity and crystalline structure of the PVDF fibers. The alpha phase of the PVDF was eliminated especially when the volatile solvent was in a ratio of 4:6. The surface area and the porosity of the PVDF nanofibers were also improved. Moreover, the penetration was also studied and reported as the relationship between the water contact angle and time. Among the volatile solvents that were studied, DMF with MA and EA at a ratio of 4:6 was the best solvent that provided fine electrospun PVDF nanofibers and the maximum tensile strength of 15.7 +/- 1.3 MPa for EA and elongation of 175.3 +/- 4.4% for MA, high water contact angle, speedy penetration rate and a high fraction of beta crystalline phase. This research presented evidence of interesting binary solvent systems with a variety of volatile solvents. (c) 2021 Society of Industrial Chemistry.

Automated summary

In this study, electrospun PVDF nanofibers were fabricated using binary solvent systems, with DMF, MA and EA at a ratio of 4:6 identified as the best solvent combination. This system produced fine fibers with high tensile strength, elongation, water contact angle, penetration rate, and a high fraction of beta crystalline phase. The research demonstrated the potential of interesting binary solvent systems with a variety of volatile solvents.