Hydrogen bonding in cellulose

The chains form a layer in the a-c crystallographic plane, where they are held together by hydrogen bonds from 0(3) in one chain to 0(6)H in the other. There are no hydrogen bonds in cellulose I between these layers, only weak van der Waal s forces in the direction of the b-axis. Native cellulose therefore has a chain lattice and a layer lattice at the same time. 

Fig. 11. Schematic representation of intramolecular hydrogen bond in cellulose molecules -+ indicates the direction of movement of electron + NMR peak shifts to lower magnetic field — NMR peak shifts to higher magnetic field...

Fig. 12a and b. Carboxymethylation towards 02—H. .. type intramolecular hydrogen bonds in cellulose I (a) and cellulose II (b)101 Shadowed area denotes crystalline part, hatched area cationized monochloroacetic acid molecule. (For S see text)... 

The comonomer complexes may be anchored on the cellulose, analogous to structures I and II, or through the interaction of zinc chloride and the cellulosic hydroxyl groups aqueous solutions of the metal halide are known to break the hydrogen bonds in cellulose and reduce crystallinity. Although radicals generated on the cellulose as the result of reaction with the catalyst may initiate polymerization of the comonomer... 

The review by Neely tabulated the characteristic frequencies of several common, substituent groups that are of interest in carbohydrate chemistry, and discussed in detail the results of the structural analysis - of pyranose derivatives in the region 730-960 cm.-. In addition, brief outlines were also given of a similar analysis (see Ref. 69) of furanose derivatives (less fruitful than that of pyranose derivatives) and of the investigations of variation in hydrogen bonding in celluloses. 

H and 0(6)H, respectively, data from relative availabilities of 0(3)H and 0(6)H may be converted to percentage of disruption of perfection of hydrogen bonding in cellulose I with the following expressions ... 

ISOGAIET AL. Intra- and Intermolecular Hydrogen Bonds in Cellulose 293... 

ISOGAI ET AL. Infra- and Infermolecular Hydrogen Bonds in Cellulose... 

Figure 3. Possible intermolecular hydrogen bond in cellulose.

Freshly produced viscose cannot be spun under normal conditions. It is therefore subjected to what is known as a postripening (maturation) by storing for about 10-100 h at 15-20 C. Here, carbon disulfide is continuously eliminated from the xanthate, and this carbon disulfide partially reforms xanthates and partially reacts with caustic soda to produce sodium trithiocarbonate and sodium sulfide. The primary OH group at the atom of the glucose residue is normally the most reactive. But because of the hydrogen bonding in cellulose, the OH group of the atoms reacts faster than those of... 

Kondo X, Sawatari C., Manley R.S., Gray D.G., Characterization of hydrogen-bonding in cellulose synthetic polymer blend systems with regioselectively substituted methylcellulose. Macromolecules, 27, 1994, 210-215. 

Forslind, E. Nuclear Magnetic Resonance Wide Line Studies of Water Sorption and Hydrogen Bonding in Cellulose. 4, 145-166 (1971). 

Klemm D, Kramer F, Moritz S, Lindstrom T, Ankerfors M, Gray D, Dorris A (2011) Nanocelluloses a new family of nature-based materials. Angew Chem 50(24) 5438-5466 Kondo T (2005) Hydrogen bonds in cellulose and cellulose derivatives. In Dumitriu S (ed) Polysaccharides structural diversity and functional versatility, 2nd edn. Marcel Dekker, New York, pp 69-98... 

FIGURE 3.8 Structures of cellulose, (a) Representation by Haworth projection formula, (b) Intramolecular and intermolecular hydrogen bonding in cellulose... 

In the 1990s there was much controversy about orientation and position of hydrogen bonds in cellulose II, Finally, it was proved that all hydroxyl group attached to Cg have almost gauche-trans (gt) orientation. Furthermore, it was found that the antiparallel origin and center chains have different conformations and the center chain is shifted in comparison to the cellulose chains at the origin of the unit cell [5]. 

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