Thermostimulated current (T.S.C) study of relaxation modes in native and regenerated cellulose below Tg. Influence of water of sorption

Three modes of relaxations were observed by T.S.C between − 120°C to − 60°C, − 40°C to 20°C, and 40°C to 60°C. The last was unstable, while the first two relaxations were more intense in regenerated cellulose and were strongly influenced by water of sorption in a manner totally different. At low temperature, the motion of methylol group is hindered as the water content increases. At medium temperature, on the contrary, the water is directly involved in the relaxation processes in different forms: First as strongly bonded water, and then as loosely bonded water, the latter acting as plasticizer.