| Abstract | The scaffold is an extracellular matrix as well as a media used in tissue engineering for growing or regenerating cells, organs etc. Although there are many conventional and rapid prototyping techniques have been applied for scaffold manufacturing but making the third dimension with the controllable pattern is still a challenge. Recently, an in house developed technique known as Electrospinning based Rapid Prototyping (ESRP) with near field theory has been applied to fabricate scaffold with controllable pattern.
Although recent studies improved the process condition but still fiber diameter was large which was not suitable for the applications. In order to increase the evaporation rate in this study, the effect of boiling temperature of the solvents were studied. Five solvents, known as DCM, Acetone, Chloroform, Toluene and DMF, with different boiling temperature were selected for making 50% and 70% weight ratio of PCL, a well-known bio degradable polymer, in those solvents. In addition, three different needle size 22g, 24g and 26g; and three different SOD 3mm, 5mm and 10mm were also investigated. The results showed that fiber diameter became smaller with decreasing the boiling temperature of the solvent, increasing the needle gauge and SOD. Furthermore, at 10mm SOD the fibers were random because more charge was accumulated in the jet and at 3mm SOD there was no whipping effect and produced straight fiber. The least straight fiber diameter was obtained by DCM 70% weight ratio concentration, 3mm SOD and 26g needle with 49.16µm. In order to obtain controllable pattern at lengthened SOD the influence of mixed solvent was also investigated. As DMF and DCM have a much different boiling temperature, five composition of DMF/DCM: 0/100, 25/75, 50/50, 75/25, 100/0 with three different needle size at 11mm were studied. Results showed that DMF/DCM (50/50) had provided the smallest straight fiber with the 29.84µm diameter as the DCM evaporate very quickly and made a change in the concentration of the solution. In conclusion, the mixed solvent has been recommended instead of pure solvents. |