Effect of Electrospinning Parameters on AIBA/PEG Fiber Morphology
The objective of this study was to determine the effect electrospinning parameters have on fiber morphology for an 80/20 wt% blend of poly(alloocimene-b-isobutylene-b-alloocimene) (AIBA) and poly(ethylene glycol) dissolved in chloroform.
The viscosity, applied voltage, and spinneret-collector gap distance were chosen as the most practical parameters to manipulate. Other parameters were held constant, while the effect of the spinning environment was accounted for by completing all of the experiments at the same temperature and humidity. The Box-Behnken design with 5 center points was used for the three factor, three level design of experiment, with the measured fiber diameter as the response.
Analysis of variance determined that solution viscosity has a significant effect on the size of the fiber, while the gap distance may only have a minor effect, and the effect of the applied voltage is insignificant. The trend of the viscosity shows an increase in fiber size in relation to an increase in solution viscosity. The same relationship between fiber diameter and viscosity is reported to occur in other polymer solutions, but the relationship between the gap distance and fiber size oppose intuition. The size of the fibers increase as distance increases, but the increase in distance would be thought to allow the fibers more time to undergo bending instabilities. The range of the spinneret-collector gap distance could be widened to allow for a better representation of its effect on the fiber size. Qualitative analysis of the images revealed that the amount of ribbon-shaped fibers increased as the viscosity increased.