Impacts of nanowhisker on formation kinetics and properties of all-cellulose composite gels

Composite gels, with cellulose nanowhiskers as the reinforcing phase and regenerated cellulose as the matrix, were firstly developed by a rapid thermal-induced phase separation followed by a regenerating process. The gelation behavior, regeneration kinetics, morphology and properties of the all-cellulose composite gel system were investigated by advanced rheometer, potentiometric titration, scanning electron microscopy, Fourier-transform infrared spectroscopy, texture analyzer and swelling testing in the presence of different amount of cellulose nanowhiskers. The results revealed that cellulose nanowhiskers could act as the "bridge" to facilitate the crosslinking of cellulose chains during gel formation process. Moreover, they can significantly improve the dimensional stability and mechanical strength of the regenerated gels. In vitro experiment demonstrated that these gels, featuring membrane-matrix hybrid structures, could be used for controlled release of macromolecules in the simulated body fluid. (C) 2010 Elsevier Ltd. All rights reserved.