抄録
Intrinsic viscosities of various kinds of cellulose acetate were determined in the mixture of methylene chloride and alcohol.
As a component of these mixtures, ethanol and methanol give almost the same [η] for cellulose acetate of acetyl contents between 52_??_61%. The tendency of the decrease of [η] with the increase of acetyl contents up to about 60% acetic acid contents were also observed in this case. Above this point [η] seemed to increase slightly with the increase of acetyl contents.
The effects of methanol contents in the mixture upon [η] of three samples, having almost the same basic d. p. but differing in their acetyl contents were also determined.
For all samples [η] increases with the addition of small amount of methanol, and reached the maximum values of [η] with the increase of methanol contents and after this maximum point [η] decreases. The higher the acetyl contents, the less amount of methanol is necessary to reach this maximum [η].
For all compositions of the mixture, [η] of samples of lower acetyl contents is higher than that of higher acetyl contents.
Using the ratio of [η] and [η]Cu-Am of the same sample the tentative Km constants for cellulose acetate of various acetyl contents are also estimated.
