%0 Journal Article
%T Size and Weight Fraction of Solvent Crystals in Poly (Vinyl Alcohol) Gel Prepared from Dimethylsulfoxide/Water Solution
%A Takahiko Nakaoki
%A Hiroyuki Yamashita
%J Open Journal of Organic Polymer Materials
%P 86-97
%@ 2164-5752
%D 2016
%I Scientific Research Publishing
%R 10.4236/ojopm.2016.62009
%X The size and weight fraction of crystals of pure ice or dimethylsulfoxide
(DMSO) in poly(vinyl alcohol) (PVA) gel prepared from a mixed solvent of DMSO/water
were determined from melting peaks observed by differential scanning
calorimetry (DSC). The depression of the melting point with respect to the equilibrium
melting point and the melting enthalpy gave the crystal size and weight
fraction, respectively. The sizes were in the range of a few nm to tens of nm,
depending on the composition ratio of the mixed solvent (DMSO/water) and the
polymer concentration. Based on the weight fraction, the critical condition at
which the whole solvent became non-freezable was estimated, and it was found to
depend on both the PVA concentration and the DMSO/water ratio. When the solvent
was pure water, the critical PVA concentration was as high as 86.4 wt%, while
for pure DMSO solvent it was 50.1 wt%.
%K Poly (Vinyl Alcohol)
%K Gel
%K Size of Solvent Crystals
%K Non-Freezable Solvent
%K DMSO
%K DSC
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=65760