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Electrospinning is a well-established technique for creating submicron polymer fibers to create distinctive functional nanostructures. Electrospinning parameters including solution concentration, tip-to-collector distance and applied voltage are adjusted to produce nonwovens with variable fiber diameter distributions. This research on the response surface methodology (RSM) is being used to model the diameter of a polyamide-6,6 (PA-6,6) nanofiber mat. The experiments were designed using central composite design (CCD) and RSM, which evaluated the interactions between the operating variables (polymer concentration, applied positive voltage, needle tip to collector distance and spinning angle) on the diameter of the PA-6,6 nanofiber. The average nanofiber diameter increased as the concentration of the PA-6,6 polymer solution increased. The model's strong regression coefficient ( R 2 = 0. 9 8) reveals that it did a desirable of predicting the diameter of PA-6,6 fibers. The experimental findings and predicted fiber diameters were in good agreement. The results demonstrate that the optimization of electrospinning process to produce the smallest nanofibers and narrowest diameter distribution (1 8 3 ± nm) combined effects of 10% polymer concentration, 21 kV applied positive voltage, 18 cm needle tip to collector distance and 60 ∘ spinning angle are substantial interacting effects that have an impact on the surface response nanofibers. The results of the research and several mathematical models will offer useful guidelines for choosing parameter settings for electrospinning PA-6,6 to achieve the required fiber diameter. By saving time, effort and money more effectively, this research will expand the field of investigation for the quality of electrospun nanofibers. Electrospinning is an established technique for creating submicron polymer fibers to create distinctive functional nanostructures. For the manufacture of nonwovens with variable fiber diameter distributions, electrospinning variables such as solution concentration, tip-to-collector distance, and the applied voltage were modified. [ABSTRACT FROM AUTHOR]

The present study is an attempt to fabricate composite nanofiber mats from polystyrene (PS) loaded with exfoliated graphite nanosheets (EGNS) by using electrospinning technique. EGNS with different weight ratios of 3, 6, and 9 wt.% were added to PS (20 wt.%). The fiber diameter and morphology of the composite nanofiber mats were investigated by scanning electron microscopy (SEM). Results revealed that as EGNS concentration was increased, the average diameter of EGNS/PS electrospun nanofibers decreased. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to investigate the thermal properties. The tensile strengths and Young's modulus of the composites improve with the increasing EGNS concentrations compared to PS nanofiber, which indicates 84% and 88% augmentation, respectively at 6 wt.% of EGNS. Also, the addition of EGNS increased thermal stability of composite nanofiber mats. [ABSTRACT FROM AUTHOR]

Basalt fiber was first treated in a mixture of formic acid (FA) and dichloromethane (DCM) to reduce its diameter down to one micrometer. Electrospinning process was utilized to produce treated basalt fiber (TBF)-reinforced nylon 6,6/epoxy (NY/EP) hybrid nanofibril composites. NY/EP polymers have been dissolved in 80:20 mixture of FA/DCM solvent to form a homogenous solution. TBFs with different weight ratios of 5, 10, 15, 20, and 25 wt% were added to NY/EP (ratio of 5:1). The morphology of the hybrid nanocomposites was investigated by scanning electron microscopy and their compositions were analyzed using energy-dispersive X-ray spectroscopy. The thermal properties were studied by differential scanning calorimetry and thermogravimetric analysis. The mechanical properties of the hybrid nanocomposites, including tensile strength and modulus, are improved with respect to NY/EP hybrid nanofibers. An increase of 76% and 87% in tensile strength and Young's modulus was acquired, respectively, at 15 wt% of TBF. Also, the addition of TBF increased the thermal stability of nanofibril composites. [ABSTRACT FROM AUTHOR]

In this work, electrospinning technique has been used to produce a new ultra-fine hybrid fiber from a solution consists of polystyrene (PS) and epoxy polymers in dimethylformamide (DMF) solvent. Five ratios of different weight percentages of epoxy in PS/DMF solutions of 4 different concentrations; 15, 20, 25 and 30 wt.% were made to obtain the minimum diameter of the produced hybrid fiber. The minimum obtained hybrid fiber diameter was found to be 897 ± 239 nm at a PS/epoxy ratio of 5:1 and 13.33 Berry's number. Adding epoxy to PS has reduced the electrospun fiber diameter from 2.64 ± 0.49 μm for PS only to 1.52 ± 0.72 μm for PS/epoxy hybrid ultra-fine fibers because of the reduction in Berry's number from 12.4 to 11.53, which gives an indication for the effect of adding epoxy on the PS molecular chain entanglement in DMF. Nuclear magnetic resonance spectroscopy results unambiguously reveal the coexistence of both epoxy and PS polymers in the hybrid fiber. We hypothesize that a hydrophopic (π-π) interaction between the benzene rings of PS and epoxy polymers could contribute to the stability of the resulting hybrid fiber under electrospinning conditions. The fact that the lack of functional groups on both of PS and epoxy polymers that can results in covalent bonding or crosslinking between the 2 polymers supports the hypothesis of hydrophopic (π-π) interaction in the stability of the hybrid fiber. Such (π-π) interaction is well known to contribute to DNA single strand helical structure via intrastrand staking of the consecutive purine and pyrimidine nucleobases. [ABSTRACT FROM AUTHOR]

Electrospinning process was optimized by using response surface methodology (RSM) to fabricate MWCNTs/PAN nanofibril composite non-woven fabrics of 180 nm average fiber diameter. The as-electrospun fabrics were hot-pressed to produce strong and flexible carbon nanofibril composite papers of 130 nm average fibril composite diameter. Dielectric constant of 300 and conductivity of 310 S/m were measured for these papers by using H10K13532-50LCR meter at 25,000 Hz. Analytical approach was introduced based on Lichtenecker modification formula to evaluate the electrical properties of the embedded MWCNTs, single nanofibers and single nanofibril composites as function in fabrics measured properties. 4156 S/m for MWCNTs, 360 S/m for carbonized electrospun PAN single nanofibers and 517 S/m for carbonized electrospun 5 wt% MWCNTs/PAN single nanofibril composites were reported. The ability to control the electrical properties of these papers over a wide range should position them as a versatile advanced material for numerous electronic, sensors and inter-connect applications. [ABSTRACT FROM AUTHOR]