The conformational energy of amylose molecule was computed a~ a function of rotations + and $ about interunit glycosidic bonds. The characteristic ratio (9 )&\ of &he mean-square end-to-end distance of the unperturbed chain to the product of n, the number of glucose residues in the chain and the squ
Configurational statistics of polysaccharide chains. Part II. Cellulose
โ Scribed by N. Yathindra; V. S. R. Rao
- Publisher
- Wiley (John Wiley & Sons)
- Year
- 1970
- Tongue
- English
- Weight
- 408 KB
- Volume
- 9
- Category
- Article
- ISSN
- 0006-3525
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โฆ Synopsis
Abstract
The characteristic ratio of unperturbed cellulose chain was computed as a function of the angle ฯ at, the bridge oxygen atom and the degree of polymerization. Very high values of the order of 40 or more, depending on the angle at the bridge oxygen atom, have been obtained for this ratio, indicating that cellulose chains are highly extended. The average dimensions of cellulose chains are found to be sensitive even for small changes in the angle at the bridge oxygen, and these chains attain the character of a random coil in very high molecular weight range (degree of polymerization greater than 2000). The large differences in the unperturbed dimensions of cellulosic chains observed in different solvents have been attributed to the possible small changes in the angle ฯ caused by specific solvent, interactions.
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