ON THE MANNAN ACETATE. I. A NEW METHOD OF PREPARATION OF MANNAN ACETATE AND SOME OF ITS PROPERTIES

R. Shinoda; C. Ashizawa

doi:10.2115/fiber1925.4.6

R. Shinoda, C. Ashizawa

Author information

JOURNAL FREE ACCESS

1928 Volume 4 Issue 1 Pages 6-13

DOI https://doi.org/10.2115/fiber1925.4.6

Details

Published: 1928 Received: - Available on J-STAGE: November 27, 2008 Accepted: December 13, 1927 Advance online publication: - Revised: -
Correction information
Date of correction: November 27, 2008 Reason for correction: - Correction: DTRECEIVED Details: Wrong : 19271215

Date of correction: November 27, 2008 Reason for correction: - Correction: ABSTRACT Details: Wrong : The authors studied on the preparation of mannan acetate from raw “Japanese konjaku powder” (Amorphophallus Konjac) which is only produced in the oriental countries, especially in Japan, and investigated some properties of the mannan acetate, such as solubility in various solvents, viscosity of the solution in a suitable solvent, stability and the tensile strength of its film, for the purpose of obtaining a substitute of cellulose acetate.
From the results of the experiments, a new method of preparation of mannan acetate was discovered and some useful information in connection with the properties were obtained.
(1) Raw “Japanese konjaku powder” is first treated with aqueous solution of C1027 and the resulted product makes into threads in order to be easily treated afterwards; then it is subjected to coagulation with glacial acetic acid and warmed with hot air. The product thus treated is heated on a boiling water bath for about 20 hrs. with continuous stirring till the reaction is completed. According to this new method, the chemicals used for reaction, such as glacial acetic acid and acetic anhydride, can be saved considerably, and the duration of reaction becomes shorter and no decomposition of konjaku mannan takes place during reaction.
(2) The composition of the mannan acetate obtained is as follws:
From the number of acetyl group it seems that the mannan acetate is triacetate of mannan.
(3) The mannan acetate is very stable and soluble in various organic solvents, among which the mixture, tetrachlorethane 4, methyl acetate 4, and methyl alcohol 2, is the most suitable solvent; 1%, solution in such a solvent has a suitable viscosity, giving a strong film.
(4) Though there are many substances containing mannan, Japanese konjaku powder is most suitable as a raw material of mannan from economical point of view.
(5) The mannan acetate can be refined satisfactorily by washing it with water.

Date of correction: November 27, 2008 Reason for correction: - Correction: AFFILIATION Details: [in Japanese]

Date of correction: November 27, 2008 Reason for correction: - Correction: PDF FILE Details: -

Corresponding author

Correction information

Register with J-STAGE for free!