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Study of polydispersity of cotton cellulose according to molecular weight

✍ Scribed by Usmanov, Kh. U. ;Sushkevitch, T. I.


Publisher
John Wiley and Sons
Year
1962
Weight
334 KB
Volume
58
Category
Article
ISSN
0022-3832

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✦ Synopsis


Abstract

A study has been made of the molecular heterogeneity of cotton fiber cellulose from fibers of different age. Analysis was carried out by the precipitation fractionation (10 to 12 fractions) and turbidity titration methods. The molecular weight distribution curves show that the cotton fiber in its early development period (grown 5 days) contains mainly low molecular weight cellulose and a small quantity of high molecular weight cellulose. Therefore, the sample is to some extent polydisperse. With continued fiber development (grown 10 to 20 days), the quantity of high molecular weight cellulose increases and the polydispersity increases also. Finally, in the late development period, the polydispersity of the sample decreases, and the fibers grown 50 days and more contain mainly homogeneous cellulose of high molecular weight. The distribution curve of the youngest fiber has only one maximum. As the fiber development proceeds, the number of maxima increases to three and reduces to one maximum again as growth is carried to maturity.


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