Modification of microcrystalline cellulose filler with succinic anhydride - effect of microwave and conventional heating
Ewa Szefer, Agnieszka Leszczyńska, Krzysztof Pielichowski
Quarterly No. 1, 2018 pages 25-31
DOI:
keywords: microcrystalline cellulose, surface modification, esterification, microwave, succinic anhydride, natural filler, biocomposites
abstract In this work the microcrystalline cellulose (MCC) filler was chemically modified by esterification with succinic anhydride (SA) in order to improve the compatibility of MCC with the hydrophobic polymer matrix. The effect of the microwave irradiation and conventional heating on the chemical structure, particle morphology and thermal stability of the cellulosic filler was evaluated by FTIR/ATR, TGA and light microscopy. The extent of surface modification of microcrystalline cellulose gradually increased with an increasing reaction time up to 90 min, and the effect was significantly pronounced under microwave irradiation as compared to conventional heating. A decreasing decomposition temperature was observed for the samples modified with SA as compared to the reference sample as a result of introducing functional side groups into the cellulose backbone and developing the surface of the MCC powder. A decrease in MCC particle sizes was observed as a result of chemical modification, especially under microwave irradiation, indicating partial hydrolysis of the amorphous regions of cellulose in an acidic environment. Smaller particles can be more equally dispersed in a polymer matrix. Applying microwave irradiation enhanced the efficiency of surface modification and produced MCC with a wider range of surface properties. Microcrystalline cellulose with adjusted surface properties can be applied as a reinforcing filler for fully biodegradable ‘green’ composites.