AbstractA study of water contained in cellulose samples softwoods dissolving pulp (DP) and hardwoods semichemical pulp (SCP) by a high resolution NMR spectrometer indicated the presence of two regions, one where the width at half value decreased rapidly with increasing water content and the other where the width at half value decreased slowly. As a result of a treatment for increasing the hydrophilicity of cellulose fibers such as beating, swelling by sodium hydroxide, and hydrolysis with hydrochloric acid, the differential energy of water binding increased in the low water content region, whereas it either did not change or decreased in the high water content region in spite of an increase in the amount of water, which is subject to the influence of the cellulosic materials. A comparison of different cellulosic materials showed that the differential energy of water binding of SCP was larger than that of DP. Moreover, an investigation of the relationship between the width at half value and the temperature indicated that different temperature ranges exist regarding binding of water, and such ranges are affected greatly by the degree of beating and the water content of the sample.
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