Analysis of Distribution of Polyvinyl Alcohol Hydrogel Nanocrystalline by using SAXS Synchrotron

Polyvinyl alcohol (PVA) hydrogel has been successfully synthesized through
freezing-thawing (F-T) process by using time-variation. This work is aimed to investigate the
distribution of nanocrystalline from the hydrogel. Fourier Transform Infrared (FTIR)
Spectroscopy, Differential Thermal Analysis/Thermogravimetric (DTA/TG), and Synchrotron
Small-Angle X-ray Scattering (SAXS) were used as the instruments in characterizing the PVA
hydrogel, respectively to observe the frequency of absorption, thermal degradation, and
structural dimensions. The functional groups which represent the PVA polymer chains were
verified on the wavenumber of 1450-1480 cm-1 and 850-870 cm-1 which is in accordance with
the stretching of –CH2 vibration mode. The absorption band of PVA polymer chains was also
found on the wavenumber of 1090-1150 cm-1 which is in accordance with the stretching of
carboxyl vibration mode (CO), and this wavenumber gave a contribution towards the
crystallinity of PVA polymer. Furthermore, the PVA polymer only interacted with the distilled
water in the sample of PVA hydrogel without experiencing any chemical interactions between
the PVA polymer and other substances. Meanwhile, the graphic of PVA hydrogel thermal
degradation shows three thermal decompositions which are indicated by three areas in which
there was sample weight loss. The second decomposition with sample weight loss was
equivalent to 61.62%-73.04% occurred at the temperature of 282-376 o
C which became the
highest sample weight loss due to polymer chain degradation. Teubner-Strey and Beaucage
models were used to analyze the characterization of structural dimension and distribution of
PVA Hydrogel nanocrystalline with SAXS Synchrotron. With a high compatibility between
the model data and the experiment, the average structural dimension of PVA hydrogel