Blend electrospinning of chitosan/polycaprolactone nanofibres

Most of the effort in electrospinning has been spent on the spinning of various single polymer·solvcnt systems. However, the high demand for materials with specific properties indicates the need to eiectrospin polymer blends. Electrospinning of blends containing a synthetic and a natural polymer enables us to combine the favourable characteristics of both (e.g. biocompatibility and sufficient mechanical strength) into one material, which is often necessary in for example medical applications. A morphological characterization of these blend nanofibres is however crucial because there is a broader range of polymer properties influencing the resulting nanofibres. In this work, chitosanlpolycaprolactone (CS/PCL) solutions were electrospun using an acetic acid/fonnie acid solvent system to create antibacterial biodegradable blend nanofibres. The fibres were characterized and the parameters influencing the stability of the production process were analysed. The fibre characterisation includes techniques such as SEM, thennal analysis (using differential scanning calorimetry and dynamic mechanical analysis) and vibrational spectroscopy (infrared spectroscopy). It was found that by adding CS to a PCL electrospinning solution, the fibre diametcrs and deviat ions can be lowered because of two possible causes. The first is the presence of more charges due to the polycationic nature, possibly reducing thc diameter by more extensive jet splaying. The second effect of CS is a significant increase in viscosity, enabling the production of electrospinnable solutions with a lower total polymer concentration. Also other specific blend fibre properties, identified by a variation of techniques, can be linked to the CS addition. Their analysis illustrates the influence of polymer blends on {he electrospinning process and the nanofibre morphology