Structural temperature transformation of the cellulose-water system using time-resolved SAXS

The main goal of the work was to examine the structural changes induced by water (D2O and H2O) in the dense cellulose him, Tomophan I, using temperatu re time-resolved SAXS and WAX measurements. We found that dry cellulose and water-saturated cellulose contains hydrophobic microregions at room temper ature. At increasing temperature microphase separation was observed, as a f ormation of a broad peak on the SAXS curves, with T-c of about 55 and 60 de grees C, depending on the kind of water. Further heating, up to 85 degrees C, causes an appearance of a set of very small peaks, generated by the cubi c structure, in SAXS. The structural changes of the system are typical for the thermo-associative process, observed in the copolymer-water systems. (C ) 2000 Elsevier Science Ltd. All rights reserved.