ISSN:
0022-3832
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
The molecular weight (determined by light scattering) of the dextran produced during the enzymatic synthesis increases while the intrinsic viscosity decreases throughout the course of the reaction. The size and spherical shape of the dextran molecule does not change significantly throughout the course of the reaction. The “branching ratio” (1,6-links to non-1,6-links) as indicated by periodate titration increases with the degree of conversion. An increase in branching would explain the intrinsic viscosity decrease and the density increase with increasing molecular weight. Fructose, which accumulates as a byproduct in the reaction mixture, is not responsible for these effects. The molecular weight of the dextran resulting from purified enzyme is much greater than that produced from crude enzyme. Because of this it is difficult to make conclusions about the mechanism of synthesis from this kind of data.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1959.1204113840
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