INVESTIGATING THE EFFECT OF MICROWAVE IRRADIATION TIME, POLYETHYLENE GLYCOL CONCENTRATION AND pH ON THE PROPERTIES OF Mg-BASED BACTERIAL CELLULOSE NANOBIOCOMPOSITE

Abstract

Mg-based bacterial cellulose nanobiocomposites (Mg-BCN) were produced assisted by microwave irradiation. In this study, the effects of the concentration of starter molecules, solution pH, and microwave irradiation time (MIT) on the properties of Mg-BCN were investigated. Tensile strength, structural properties, morphology and thermal stability of the nanocomposites were evaluated. According to the obtained results, an increase in the concentration ratio of starter molecules, pH, and MIT increased the formation of MgO, in comparison with Mg(OH)2. The nanocomposites synthesized with the 1:2 and 2:1 concentration ratio of magnesium acetate to polyethylene glycol, at pH 11 and with 3 minutes of MIT, had the largest tensile strength and crystallinity. Meanwhile, the opposite results were obtained with 1:1 and 1:0 ratios, at the mentioned pH and time. According to FESEM analysis, at pH = 9, the nucleation rate decreased and smaller particles were formed. Moreover, the results showed decreased possibility of agglomeration in the presence of polyethylene glycol (PEG). TGA results indicated that the thermal stability of all Mg-based nanocomposites is higher than that of pure cellulose. In addition, the maximum weight loss temperature in all treatments involving PEG was higher than in the case of the samples treated without PEG.