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The dynamic mechanical properties of cellulose hydrogels under uniaxial compression have been studied over a wide ränge of water Contents (0.14 g/g -5 g/g) at three temperatures (20 °C, 50°C, 80°C) and four frequencies (0.2, l, 3,10 Hz). The dynamic storage modulus E' decreases almost by a factor of 1000, whereas the loss factor tan increases monotonically over the studied water content interval, The dynamic storage modulus decreases with an increase in temperature. Although the cellulose gels are transformed by water from the glassy state to the rubbery state, no maximum in the loss factor was observed. It is suggested that the crystallites and the hydrogen bonds in the gel structure act äs crosslinks, shortening the elastically effective cellulose chains to such an extent that cooperative cellulose chain motion in the transition region is lost. This results in the complete suppression of the transition.

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