Cellulose I-ethylenediamine complex

Some 39 independent reflections are observed in the fiber diagram of ramie cellulose I-ethylenediamine complex, and there are a further 36 that are predicted within the range of these data, but which are too weak to detect. Elemental analysis indicates the presence of one ethylenedlamlne per glucose residue and density considerations require dlsaccharlde units of two chains per unit cell. 

Figure 3. Structure of Ramie cellulose I - ethylenediamine complex (30] (a) 010 projection (b) projection.

The one-chain unit cell prescribes an unstaggered array of parallel chains and thus the rearrangement from the original cellulose I structure that has occurred is very similar to that which occurs on formation of the ethylenediamine complex. A one chain unit cell is also seen for the 1,2-diaminopropane complex, and this structure appears to be similar, except for minor modifications of the a and b dimensions. 

Unit cells of pure cellulose fall into five different classes, I—IV and x. This organization, with recent subclasses, is used here, but Cellulose x is not discussed because there has been no recent work on it. Crystalline complexes with alkaU (50), water (51), or amines (ethylenediamine, diaminopropane, and hydrazine) (52), and crystalline cellulose derivatives also exist. Those stmctures provide models for the interactions of various agents with cellulose, as well as additional information on the cellulose backbone itself. Usually, as shown in Eigure la, there are two residues in the repeated distance. However, in one of the alkah complexes (53), the backbone takes a three-fold hehcal shape. Nitrocellulose [9004-70-0] heUces have 2.5 residues per turn, with the repeat observed after two turns (54). 

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