High molecular weight cellulose acetate membrane electrospinning: Parameters experimental optimization

Cellulose acetate (CA) drew great efforts in the membrane fabrication field, as it is a biodegradable polymer. However, electrospinning of CA with high molecular weight, which affects the spinnability, is still challenging. In this study, CA, with a relatively high molecular weight, was electrospuned at differentconditions to produce uniform and bead-free fibers. The target application of the optimized CA membrane is the membrane distillation process, which requires a low fiber diameter and narrow distribution. Results of the preliminary study revealed that the minimum and maximum limits for the investigated factors are CA concentration (13-17 wt%), tip-to-collector distance (TCD) (9-18 cm), applied voltage (14–20 Kv), and flowrate (0.5–2 ml/h). Electrospinning parameters optimization was designed using response surface methodology (RSM) with Box-Behnken Design (BBD) model. The considered parameters were CA concentration, TCD, and applied voltage. The prepared membranes' morphological structure and average fiber diameter were analyzed using SEM analysis and ImageJ software. With p-values less than 0.0001 and an R2 value of 0.9729, the analysis of variance (ANOVA) demonstrated that the suggested quadratic empirical model significantly agreed with the experimental investigation. The optimal parameters were, therefore, a concentration of 13 wt% CA, an applied voltage of 16.47 Kv, and a TCD of 17.99 cm. The verification experiment revealed a relative error value of 7.5%.