Porous electrospun polycaprolactone fibres: Effect of process parameters

The effect of electrospinning process parameters (solution flow rate, applied voltage, spinning distance) on the size and surface morphology of porous electrospun poly(ε-caprolactone) was investigated in this study. Response surface methodology was implemented for the design and conduction of electrospinning experiments. The feed solution was a 12.5% w/v poly(ε-caprolactone) (PCL) solution in a binary solvent mixture of 90%v/v chloroform/ dimethyl sulfoxide. Spinning distance of 10-25 cm, applied voltage of 10-25 kV and feed flow rate of 0.5-5 ml/h were the range of limiting values of the independent variables used for the development of a central composite design. Second order polynomial equations, correlating electrospinning process parameters to relative pore coverage and fibre average diameter were developed and validated. An increase in any of the electrospinning process parameters favoured pore formation and fibre diameter increase. Under the experimental conditions investigated, the relative pore surface coverage was 15.8-31.9% and the average fibre diameter was in the range of 1.6-3.3 μm. Applied voltage was proven to be the parameter with the strongest impact on both, fibre diameter and surface morphology.