Mass absorption
The dry sample was weighed on a Mettler Toledo XS 104 analytical balance
and then placed in a 50 mL beaker filled with isopropanol. The beaker
with the sample and isopropanol was placed in a desiccator, to which an
oil pump was connected. The sample was degassed for 30 min. After this
time, the sample in the isopropanol beaker was removed from the
desiccator and beaker. Excess i PrOH was removed and weighed on an
analytical balance. Each experiment was performed in 3 replications.
Water absorption was calculated from the formula:
\begin{equation}
A_{m}=\frac{m_{w}-m_{d}}{m_{d}}\times 100\%\nonumber \\
\end{equation}where:
m w - mass of the wet air-weighed sample, g
m d - dry mass of the air weighed sample, g
A m - mass absorption,%