Acetone, a Sustainable Solvent for Electrospinning Poly(ε-Caprolactone) Fibres: Effect of Varying Parameters and Solution Concentrations on Fibre Diameter

Abstract

Electrospinning commonly requires a solvent carrier to transform polymer materials from one solid form to another. The types of solvents are often classed as toxic and hazardous and have potential long-term impacts on the environment and the health of the user. Acetone is a sustainable and non-toxic solvent, but has received limited use within the electrospinning sector-particularly for biocompatible polymers, such as poly(e-caprolactone) (PCL). This paper documents the ability to electrospin PCL dissolved in acetone and the effects of spinning parameters on the morphology and diameter of the collected fibres. Depending on the end use of the collected fibres it is important to understand how the parameters interplay and affect fibre morphology and diameter, especially if fibres of a specific form and size are required, for example, to mimic the extracellular matrix of tissues. This paper investigates the effects of flow-rate (0.05 and 0.1 ml/min), voltage (15 and 25 kV), distance (5 and 10 cm) and voltage-distance combined, on different concentrations of poly(e-caprolactone)/acetone solutions (5, 7.5 and 10 %w/v) in terms of fibre morphology and fibre diameter. Overall, solutions of PCL dissolved in acetone could be electrospun and, in general, the trends observed with altering spinning parameters followed those documented for other polymer/ solvent systems. This calls for the increased use of less hazardous and more sustainable solvents, such as acetone, for electrospinning applications.

Travelling along the Clinical Roadmap: Developing Electrospun Scaffolds for Tendon Repair

“…Solvents used for dissolution of the polymers were acetone (PCL) and 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) (PCL, PLGA 85:15 , and PCL: PLGA 85:15 ). All solutions were at a concentration of 10% w/v, which had been previously determined in a separate study [8]. Of the four polymer/solvent combinations trialled (Figure 2), PCL dissolved in HFIP resulted in smooth, bead-free fibres and fine fibre diameter (0.44 m) [9].…”

Characterizing the Reproducibility of the Properties of Electrospun Poly(d,l-Lactide-Co-Glycolide) Scaffolds for Tissue-Engineered Blood Vessel Mimics

“…Higher concentrations create higher viscosities, which stops fiber formation. It has also been shown that increasing the concentration increases the fiber diameter and results in more uniform fibers [60][61][62]66 .…”

“…Additionally, an increase of voltage results in a decrease of fiber diameter with no change in the pore size distribution 64 . It has been postulated that the reduction in fiber diameter can be attributed to an increased acceleration of the polymer jet which caused further charge repulsion and thinning as the jet traveled toward the collector 62,63,66 . Different solutions have been shown to have the opposite effect;…”

“…Several electrospinning parameters can be altered to reduce fiber diameter, including reducing the flow rate 57,62 , increasing the voltage 62,63,66 , decreasing the solution concentration 61,62,66 , and increasing the gap distance 62,63,66 . More experiments can be performed to obtain smaller fibers by testing each of these parameters However, other studies have also used other solvents with PLGA and obtained smaller fibers, including tetrahydrofuran (THF);…”

Printing Accuracy of Large Scale Melt Electrospinning 3D Printer in a Direct-Writing Mode

“…Of ME and SE, SE produces finer fibres with diameters reaching as low as 5nm (Bosworth, & Downes, 2012). To achieve these thin fibres, the process of SE involves a solution being pumped through a very thin nozzle.…”