Optimal fabrication of nanofiber membranes from ionized-bicomponent cellulose/polyethyleneoxide solutions

The effect of cellulose acetate (CA)/polyethyleneoxide (PEO) ratio (0.5–1.5 wt%) and lithium chloride (LiCl) content (0.25–0.75%, w/v) on the viscosity, surface tension and electrical conductivity (EC) of the solutions and diameter of the fabricated nanofiber membranes (NFMs) were optimized using response surface methodology-central composite rotatable design (RSM-CCRD). The NFMs were composed of non-woven fibers with maximum diameter of 121.70 ± 33.40. Second-order polynomial models with high R2 values (0.977–0.998) were developed using multiple linear regression analysis. Results showed that the NFMs diameter and morphology were significantly affected by CA and LiCl contents (p < 0.0001). The overall optimum region was found to be at the combined level of CA to PEO ratio of 1.5 wt% and LiCl content of 0.5% (w/v). At the optimum point, the viscosity, surface tension, EC and diameter were 0.425 ± 0.036 Pa s, 36.21 ± 1.25 mN/m, 0.383 ± 0.014 ms/cm, and 82.19 ± 3.01 nm, respectively. The most uniform and bead-free NFMs were fabricated from the solution formulated with 1 wt% CA/PEO and 0.85% (w/v) of LiCl content.