Influence of process variables on the yield and diameter of zein-poly(N‑isopropylacrylamide) fiber blends obtained by electrospinning

• Published in: Journal of molecular liquids 2019-10, Vol.292, p.109971, Article 109971
• Main Authors: Vicente, Ana Clara B., Medeiros, Gabriela B., do Carmo Vieira, Délia, Garcia, Francielle P., Nakamura, Celso V., Muniz, Edvani C., Corradini, Elisângela
• Format: Article
• Language: English
• Subjects: Electrospinning; Poly(N‑isopropylacrylamide); Process parameters; Zein
• ISSN: 0167-7322; 1873-3166
• DOI: 10.1016/j.molliq.2018.11.061

In this study, zein-poly(N‑isopropylacrylamide) fiber blends (PNIPAAm) were obtained by electrospinning. The effects of solution concentration and process parameters were evaluated by means of factorial design. The concentration proved to have a stronger effect on fiber diameter than the flow rate, although a positive interaction was identified between the factors of concentration and flow rate. Fibers with smaller diameters can be obtained at lower concentration within the electrospinnable window. The simultaneous increase in flow rate and concentration increases the fiber diameter. Concentration and flow rate have similar effects on the yield response. Higher yields can be obtained using higher concentrations and higher flow rate rates. FTIR confirmed the presence of zein and PNIPAAm in the fibers and indicated some interaction between the two polymers. The fibers showed behavior hydrophilic below 33 °C and hydrophobic from 38 °C. The mean diameter of the fibers increased with increasing solution viscosity due to the greater entanglement of the polymer chains. VERO cell viability tests made at 37 °C showed at least >90%, viability which means that the samples did not inhibit cell growth after 72 h of incubation, demonstrating good biocompatibility. •Zein-poly(N‑isopropylacrylamide) fiber blends (PNIPAAm) were obtained by electrospinning.•Factorial design was used for evaluating the solution concentration and process parameters effects.•Concentration of polymer solution has stronger effect on fiber diameter as compared to the flow used for electrospinning.•Lower concentration of polymer solution provides smaller electrospun fiber-diameters.•The fiber diameter was related to the solution viscosity due to the entanglement of the polymer chains.