抄録
Viscosities of dilute solutions of various cellulose acetate butyrate samples differing in acetyl and butyryl contents were determined using various solvents.
By plotting ηsp/c against C after Huggins′ equation, the linear relations were obtained and from these curves, [η], k′, initial slope k′[η]2 were calculated for each solution. Using water and n-hexane as the diluent, dilution ratio (DR) was also determined.
For all samples tested [η] are highest in acetic acid and lowest in the mixture of methylene chloride and ethanol, while methyl acetate and acetone give the intermediate values.
The relations between [η], k′, initial slope and DR are rather complicated.
In methyl acetate and acetone the values of k′ and initial slope are higher than those in acetic acid and the mixture of methylene chloride and ethanol.
DR with water showed the parallel tendency to the variation of [η]., but DR with n-hexane showed more complicated behavior.
The effects of the butyryl contents of the samples on these relations are qualititavely discussed.
Using the Staudinger's equation and the measured [η] in cuoxam the tentative Km constants for each samples differing in the acyl compositions in these solvents, were also determined.
These Km constants differ slightly with solvents and butyryl contents of the samples and lay between 5_??_7×10-4, taking Km for cellulose in cuoxam as 5×10-4.
