PREPARATION AND CHARACTERIZATION OF NON-WOVEN NANOFIBROUS MEMBRANES OF CHITOSAN AND POLY(ETHYLENE OXIDE) IN A HIGH ETHANOL CONCENTRATION

Abstract

The potential use of non-woven fibrous membranes of chitosan (CS) and poly(ethylene oxide) (PEO) in the filtering system application has appealed to the worldwide research concern. However, CS and PEO solution blends and the CS nanoparticles (CSNPs)-PEO suspensions using a high concentration of ethanol as the PEO solvent with a low CS/PEO ratio have not been studied. CS in 2% acetic acid solution and PEO in 96% ethanol blends were electrospun to form fibrous membranes. The CS concentration in acetic acid varied by 0, 0.5, 1.0, and 1.5 wt.%, and a CS/PEO ratio was 10/90. The addition of 0.5 and 1.0 wt.% CSNPs to PEO solution was used for comparison. The current research aims to explore the impact of CS concentration on the physical and mechanical properties of the CS/PEO non-woven fibrous membranes. CS solution's effect on the fiber morphology and mechanical property is compared to that of CSNPs. Visual observation demonstrated a wrinkle pattern formed on almost all the nanofibrous membranes due to a high evaporation rate of the used PEO solvent. However, the fiber morphology of the membranes was not significantly affected. Differential scanning calorimetric (DSC) analysis indicates that the degree of crystallinity increases with CS concentration. It corresponds to the improvement of the tensile strength of the CS/PEO membranes, especially by adding 1.5% CS concentration. Nonetheless, CSNPs loading improves tensile strength of CSNPs/PEO higher than that of CS/PEO at the same CS concentration. Introducing CSNPs to the PEO crystal structure can improve the crystallinity higher than by inducing intermolecular hydrogen bonding of CS and PEO chains.