Papers by Author: Wei Min Kang

Abstract: PU/CS nanofiber membrane was prepared by means of electrostatic spinning. The morphology of nanofiber membrane was examined by a scanning electron microscope (SEM), and the mechanical property, water absorption, moisture permeability and antibacterial performance were also investigated. The results show that the diameter and mechanical property of PU/CS nanofiber decreased with the increase of the content of CS. However, the water absorption, moisture permeability and antibacterial performance were improved significantly with the addition of CS.

Abstract: A kind of pullulan biopolymer nanofibers with diameter of 100～700nm were obtained using redistilled water as solvent through electrospinning technology in this paper. The effects of the spinning solution concentration, applied voltage, flow rate and capillary–screen distance on morphology and diameter distribution of pullulan nanofiber were studied by SEM. The results show that, different parameters had great influence on nanofibers’ morphology and diameter. The optimal parameters of pullulan nanofibers electrospinning were: 22wt.% spinning solution concentration, 31 kV voltage, 20 cm capillary–screen distance and 0.5ml/h flow rate.

Abstract: Polyurethane-poly (vinyl alcohol)/chitosan (PU-PVA/CS) blend nanofiber nonwovens were successfully prepared by coelectrospinning in this paper. The morphology, diameter and structure of the electrospun nanomaterials were examined by SEM and FITR, and their mechanical properties were tested. The diameter distribution of the nanofibers was measured by Image-Pro Plus. The results show that the ideal nanofibers with the diameter in 50-350 nm can be obtained with the proper technical parameters of PU and PVA/CS nanofibers as follows: the spinning voltage at 30 kV and 40 kV, the extruding speed at 6 mL/h and 0.5 ml/h, the collecting distance at 150 mm and 200 mm, respectively.

Abstract: Alumina fiber, a kind of inorganic fiber, was widely used in many fields owing to its excellent performance. CeCl₃/AlCl₃/PVP was used as spinning solution for producing organic-inorganic hybrid fiber by electrospinning, then, alumina fiber doped cerium can be successfully obtained after high temperature calcination. In the paper, the influence of CeCl₃ to the crystallization and thermal stability was discussed. The results show that alumina nanofiber with average diameters of 200nm-800nm are obtained by calcination of the as-prepared fibers .The addition of CeCl₃ significantly delay the crystallization transformation process of alumina fiber, while the formation of CeO₂ reduce diffusion rate of Al3+, eventually, imped the phase transformation of Al₂O₃ and improve its thermal stability.

Abstract: In this paper, using the wasted beverage cans, the alumina nanofibre was fabricated via electrospinning method. The effects of various processing variables on the morphology of electrospun nanofibres were discussed, such as solution concentration, spinning voltage strength and deposition distance. The results showed that the proper solution could be obtained after the surface of the beverage cans were treated. When the PVP concentration was 6%, spinning voltage was 30kv and the deposition distance was 13cm, the alumina nanofibre with uniform diameter, excellent structure and good morphological feature could be obtained.

Abstract: In this paper polyurethane (PU) / polyaniline (PANI) nanofibers were successfully prepared via electrospinning with N, N-dimethylformamide (DMF) and tetrahydrofuran (THF) mixture (1:2 mass ratio). The morphology, diameter and structure of the electrospun nanofibers were examined by scanning electron microscopy (SEM) and the diameter distribution of nanofibers was measured by Image-Pro Plus. Results indicate that the morphology, diameter and uniformity of the fibers were influenced by solution concentration, applied voltage, capillary–screen distance and flow rate greatly, and the finer and uniform nanofibers were electrospun from total solid content of the spinning solutions at 8 wt. %, PU and PANI with ratio of 10/1 (w/w), the spinning voltage at 35 kV, the collecting distance at 15 cm and the extruding speed at 6 ml/h.

Abstract: A new kind of polypropylene spun-bonded nonwovens (PSN) with excellent hydrophilic property was developed after finished with S 6237 hydrophilic agent. The infiltration time (IT) and the runoff (RO) were tested to evaluate the hydrophilicity of the finished PSN. The impacts of different agent concentrations, drying temperatures and drying time on hydrophilicity were investigated and PSN before and after finished were compared concerning softness, air penetrability, moisture regain and stretch performance. The results show that the optimum technological condition for the hydrophilicity is agent concentration: 4 %, drying time: 30s and drying temperatures: 120 °C, and the IT and the RO for the first time are 1.82s and 1.8% respectively. Softness and air penetrability of the finished PSN were improved significantly but mechanical performance was merely decrease a little.

Abstract: . In this paper, thin palladium (Pd) membranes, which are supported on alumina nanofiber nonwoven produced by electrospinning method, were prepared by electroless plating method. The influence of different pretreatment methods (iron wire activation) and reducing agent (sodium hypophosphite and hydrazine hydrate) on the structure of Pd membrane were studied. The morphology, surface element and crystal structure of the Pd membrane were investigated by SEM, EDS and XRD. The results showed that the compact Pd membrane was formed on the alumina nanofiber nonwoven when the pretreatment method of iron wire activation was adopted and the reducing agent of sodium hypophosphite was used, which will be applied widely in hydrogen separation area.

Abstract: In this paper polylactide (PLA) nanofibers were successfully prepared via electrospinning using low toxic 1,4-dioxane and acetone as co-solvents. The morphology of nanofibers was studied by scanning electron microscopy (SEM) at the different weight ratios of co-solvent, concentrations of spinning solution, electrostatic voltages and collecting distance. Results indicate that the finer and uniform nanofibers were electrospun from the concentration of the spinning solutions at 8 wt.%, 1,4-dioxane and acetone with ratio of 40/60 (w/w), the spinning voltage at 20kV, the collecting distance at 180 mm and the extruding speed at 5 mL/h.

Abstract: Electret filter composed of permanently charged electret fibers is a good material for environmental protection. A novel kind of electret melt-blown nonwovens (EMNs) doped with nano-tourmaline was developed by corona charging in this paper. The structure of web, mechanical properties, surface charge density and filtration efficiency of samples were discussed. The results showed that the structure of EMNs became loose and the initial surface charge density was increased markedly. Furthermore, the EMNs exhibited higher filtration efficiency and lower pressure drop, especially the content of nano-tourmaline was about 6 wt. %.