Microwave-enhanced hybridizations of biopolymers with silica: effective method for rapid preparation and homogeneous dispersion

Effective hybridization of biopolymers such as chitosan or lignin was conducted by microwave-assisted sol-gel reaction of several alkoxysilanes such as tetramethoxysilane (TMOS), methyltrimethoxysilane (MeTMOS), and 3-aminopropyltrimethoxysilane (APTMS). The hybridization proceeded rapidly and efficiently via inhibition of aggregates derived from intermolecular hydrogen bonding in the biopolymers as compared with the conventional heating as a traditional method due to activated hydroxyl groups of both the biopolymers and alkoxysilanes by microwave irradiation. The composition and the thermal properties of the polymers hybridized under microwave irradiation were almost identical to those prepared by the conventional method using TGA analysis and FT-IR spectroscopy. However, the homogeneity on the surface of the hybrid obtained under microwave irradiation was better than that under conventional heating by measuring the SEM and nitrogen adsorption porosimetry analysis.