Effects of thermal and chemical treatments on the structural stability of cellulose acetate nanofibers

Cellulose nanofibrous membranes made by electrospinning are characterized by their high porosity and interconnectivity, and therefore, considered potential candidates for ultrafiltration processes. Due to the difficulty to dissolve cellulose, electrospinning of cellulose derivatives followed by regeneration of cellulose is a more convenient approach. Using a previously optimized set of electrospinning parameters, the effects of thermal and chemical treatment of cellulose acetate (CA) nanofibers on their structural stabilities are thoroughly discussed in the current article. Nanofibrous membranes initially made from solutions containing 10-20 wt% CA were investigated. Structural stability was monitored using infrared spectroscopy (IR), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) techniques. Results showed the possibility of de-acetylation of CA nanofibers during the thermal treatment step, more precisely on the procedure and temperature of treatment. Combining thermal and alkali treatment of CA nanofibers was found crucial to their morphologies. Optimization of these processes is, therefore, attempted. Phase purity of the regenerated cellulose nanofibers was investigated. (C) 2010 Elsevier Ltd. All rights reserved.