SORPTION E X P E R I M E N T S WITH CELLCLOSE S I T R A T E . 11. Sorption of T'apours by Cellulose Sitrate BY L. R U B E N S T E I S
Introduction
1.
When the work described in Part I was completed it appeared that there was a number of aspects of the subject which required further treatment. The most important of these were (I) the relationship which it was found held in the majority of cases between the sorption of the nitrocotton and its nitrogen content, ( 2 ) the reversibility of sorption values, ( 3 ) the time necessary to obtain equilibrium in sorption experiments and (4) the question of sorption and viscosity. I t was thought important first to try to confirm the values of the sorption obtained by the previous investigators with the series of nitrocottons and further to extend the series and the determination of their sorption. For this purpose nitrocottons of nitrogen content 1 0 . 2 to 1 1 7 and ~ about I Z % ~ , n'ere added to the ones already used, while many samples previously used were restablised. -4complete list of the nitrocottons and particulars regarding them are contained in Table I. TABLE 1 Analytical Data of the Sitrocotton Samples used in the Sorption Experiments
yc S?
Sitrocotton Sample
uncorrected
.4sh free
-4sh
I
10.26
I O .2 3
o 18
yc xp i
Viscosity in 6% concentration in 95%; acetone c.g.s. units
r-
105 1;
0
conc. IOC(
2
10.63
10.64
0
3
10.82
I O .84
0 Ij
10
Heat,Test B. 8: J. Test min. mgm. Nl'grn.
I
