Studies on Bound Water of Cellulose by Differential Scanning Calorimetry

Abstract

The crystallization and melting of adsorbed water on cellulose samples such as cotton, kapok, linen, jute, various rayons, and wood cellulose have been studied using a differential scanning calorimeter (DSC). Two exothermic peaks of crystallization of adsorbed water on the cellulose samples are observed. One is a sharp peak (Peak I) observed at about 255 K in a DSC curve; the other is a broad peak (Peak II) observed at about 230-250 K. Judging from the amounts of water calculated from the results obtained by the DSC study, there seems to be some nonfreezing water which does not crystallize. Therefore, we have categorized water adsorbed on cellulose samples as one of three different kinds: free water (Peak I), freezing bound water (Peak II), and nonfreezing bound water.

The bound water content is dependent on the degree of crystallinity of cellulose samples. The amounts of bound water estimated are from 1.0 to 2.2 moles per one glucose unit of cellulose. However, the amount of water bound to each glucose unit was 3.4 moles, if we took into consideration that water diffuses only into the amorphous region of each cellulose sample.

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References

Andronikashvili, E.L. , Mrevlishvili , G.M. , Japaridze, G. Sh. , Sokhadze, V.M. , and Kvavadze, K.A. , Thermal Properties of Collagen in Helical and Random Coiled State in Temperature Range from 4 to 300 K, Biopolymers 15, 1991 (1976).

Ayer, J.E. , Determination of Primary Adsorbed Water in Cotton Fibers by Drying Techniques , J. Polym. Sci. 21 , 455-462 (1956).

Crank, J. , "The Mathematics of Diffusion," Clarendon Press , Oxford, 1956, p. 254.

Dragomir, C.T. , Ungureanu, D. , Barbier , A. , Stefansen, D.T. , and Perianu, M. , Modifications of Ouabain Inhibition of Xenon Accumulation in Red Blood Cells. Implications Regarding Cell Water Structuring , Physiol. Chem. and Phys. 11, 225(1979).

Eisenberg, D. and Kauzmann, W. , "The Structure and Properties of Water," Oxford University Press, London, 1969, p. 93.

Froix, M.F. and Nelson, R. , The Interaction of Water with Cellulose from Nuclear Magnetic Resonance Relaxation Times, Macromolecules 8, 726 (1975).

Goring, D.A.I. , The Effect of Cellulose on the Structure of Water: View I, Transactions of 6th Symposium of Paper Physics, 4-1 Cambridge ( 1978).

Harris, M. , "Handbook of Textile Fibers," Intersci. Pub. Inc. , New York, 1954, p. 191.

Hatakeyama, H. , Nakamura, K. , and Hatakeyama , T. , Studies on Factors Affecting the Molecular Motion of Lignin and Lignin-Related Polystyrene Derivatives Pulp Paper Mag. Canada 6, TR105 (1980).

10.

Hatakeyama, T. , Nakamura, K. , and Hatakeyama , H. , Determination of Bound Water Contents Adsorbed on Polymers by Differential Scanning Calorimetry , Netsusokutei 6 , 50 (1980).

11.

Hatakeyama, H. and Hatakeyama, T. , Structural Change of Amorphous Cellulose by Water- and Heat-Treatment, Macromol. Chem. , in press.

12.

Hermans, P.H. and Weidinger, A. , X-Ray Studies on the Crystallinity of Cellulose , J. Polym. Sci. 4 , 135-144 (1949).

13.

Hermans, P.H. and Weidinger, A. , Estimation of Crystallinity of Some Polymers from X-Ray Intensity Measurements, ibid 4, 709-723 (1949).

14.

Long, F.A. and Richman, D. , Concentration Gradients for Diffusion of Vapors in Glassy Polymers and Their Relation to Time Dependent Diffusion Phenomena, J. Amer. Chem. Soc. 82, 513 (1960).

15.

Magne, F.C. , Portas, H.J. , and Wakeham, H. , A Calorimetric Investigation of Moisture in Textile Fibers, J. Amer. Chem. Soc. 69, 1896 (1947).

16.

Magne, F.C. and Skau, E.L. , Nonfreezing Water and Nonfreezing Benzene Capacities of Cottons and Modified Cottons, Textile Res. J. 22, 748-756 (1952).

17.

McLaren, A.D. and Rowden, J.W. , Sorption of Water Vapor by Proteins and Polymers: A Review, J. Polym. Sci 7, 289-324 (1951).

18.

Nelson, R.A. , The Determination of Moisture Transitions in Cellulosic Materials Using Differential Scanning Calorimetry, J. Appl. Polym. Sci. 21, 645-654 (1977).

19.

Nomura, S. , Hiltner, A. , Lando, J.B. , and Bear, E. , Interaction of Water with Native Collagen Biopolymers 15, 1991 ( 1976).

20.

Preston, J.M. and Tawde, G.P. , Freezing Point Depression in Assemblages of Moist Fibers J. Textile Inst. 47, T154-T165 (1956).

21.

Stone, J.E. and Scallan, A.M. , A Structural Model of the Cell Wall of Water-Swollen Wood Pulp Fibers Based on Their Accessibility to Macromolecules , Cell. Chem. Technol. 2, 343 ( 1968).