Syringe pump ne 300

Fibrous materials of different composition were obtained by electrospinning: CA, CA/PEG, and CA/PEG/QUE. Three types of solutions were prepared for electrospinning in acetone/water 80/20 v/v: (i) CA, (ii) CA/PEG (80/20 w/w), and (iii) CA/PEG (80/20 w/w) with QUE (10 wt% in respect to total polymer weight). The total polymer concentration was 10 wt%.
The electrospinning apparatus used for the preparation the fibers consisted of a pump with adjustable speed and 5 mL syringe (12 mm internal diameter) fitted to a metal needle with a tip (size: 20GX1½) connected to the positively charged electrode of a high voltage power supply (up to 30 kV). The spinning solutions were placed in the syringe. The electrospinning was performed at 21 °C, relative humidity −50%, applied voltage of 25 kV and a tip-to-collector distance of 15 cm to the grounded rotating metal cylindrical collector (1000 rpm). The constant delivery rate of the spinning solutions of 3 mL/h was provided by a pump Syringe Pump NE-300 (New Era Pump Systems, Inc., New York, NY, USA).

For electrospinning, we used a point-plate configuration, where the PS/LC blend was loaded into a syringe fitted with a stainless-steel needle (0.508 mm I.D.) and attached to a power supply (Matsusada Precision Inc., model AU-40R0.75 with positive polarity, Kusatsu, Shiga, Japan). A flow rate of 0.5 mL/h (New Era Pump Systems syringe pump NE-300, Farmingdale, NY, USA), collecting distance of 10 cm between the tip of the needle and the ground collector plate covered with foil and applied voltage (positive polarity) of 5–12 kV were used. Blends were prepared and electrospun at temperatures between 19 and 22 °C and relative humidity between 11 and 20%.

PAN and AgNO₃ were dissolved in DMF and stirred homogenously at room temperature to prepare the stock solution for the subsequent electrospinning process. We used a 1 mL syringe (inner diameter, 4.7 mm) to store the stock solution and attached a 20G needle (inner diameter, 0.6 mm; outer diameter, 0.9 mm; length, 25.4 mm) and then placed this apparatus in the injection pump (New Era Pump Systems, Inc., Syringe Pump NE-300, St. Farmingdale, NY, USA). A 10 × 10 cm² iron sheet was utilized as an electrically grounded collector. The positive electrode of the high-voltage power supply was clamped on the needle, and the grounded wire was clamped to the iron sheet collector. The parameters were set as follows: voltage, 17 kV; flow rate, 7 μL/min; working distance, 12 cm to maintain a stable corn-jet mode electrospinning. After all the parameters were precisely set and a high-voltage power supply was applied, an electrical field was established between the capillary tube and collection substrate, and the electrospun PAN nanofibers were deposited on the collector. During the electrospinning process, we controlled the humidity of the working environment at approximately 40–50% for the pure PAN nonwoven mat (dehumidifier, Kolin Inc., Taipei, Taiwan) and approximately 20–30% for the AgPAN nonwoven mat by using a dehumidifier.