Electrospinning of PCL

Electrospinning of PCLAim:

To observe the formation of Poly Caprolactone fibers at different parameters, using electrospinning technique.Apparatus required:

High voltage source, metered syringe pump, metal target, syringe, magnetic stirrer, glass vials, hollow needle etc.

Chemicals required:

Methylene chloride, methanol, poly caprolactone, isopropyl alcohol etc.Procedure: 0.85 gm of poly caprolactone was dissolved in a mixture containing 7 ml of methylene chloride and 3 ml of methanol The solution was stirred for 30 minutes using a magnetic stirrer, in order to dissolve the polymer in the mixture

The solution was loaded into a 3 ml syringe and the tip of the needle was connected to a high voltage source

The electrospinning was performed at different parametersObservation: Electrospinning of Poly Caprolactone using various parameters were observed:

Voltage: 10 KVa, Concentration of PCL: 8.5%

Flow rate: 1 ml/hr, spinning time: 5 mins

Droplet formation was observed at the tip of the needle, while formation of beads was observed in between the fibers in the construct. The viscosity of the PCL solution at 8.5% concentration was very low. At the given voltage (10 KVa), because of the low viscosity droplet formation was observed at the tip of the needle during electrospinning. The droplets clogged at the tip of the needle during the experiment and they interrupted the formation of fibers. When the flow rate was increased to 2 ml/hr, 3 ml/hr, 4 ml/hr, the droplets coming out from the needle escaped the applied voltage. As a result, there was a continuous flow of solution in the form of droplets and no fiber formation was observed. For the given concentration of PCL (8.5%), electrospinning of PCL at 20 KVa and different flow rates (1 4 ml/hr), yielded better fibers than at 10 KVa.

It was observed that the fiber formation was dependent on all the factors. At low concentration (8.5% PCL) and low voltage (10 KVa), bead formation was observed. While at low concentration (8.5% PCL) and at high voltage (20 KVa) better fiber formation was observed. This is because, no clog formation was observed at the tip of the needle. The spinning time has not made a big impact on the formation of fibers at higher flow rates (4 ml/hr). Spluttering of fibers was observed at higher flow rates. Hence, fibers hardly deposit on the construct. At lower flow rates, spinning time made a considerable impact. The density of fibers increased with spinning time.