Influence of Physical Aging on the State of Water Strongly Bound by the Polyvinylpyrrolidone-Poly(ethylene glycol) Complex by Broad-Line ~1H NMR Data

摘要

The mobility of the components of a mixture of high-molecular-weight polyvinylpyrrolidone and poly(ethylene glycol) containing 36 vol % of PEG with a molecular mass of 400 and about 1 wt % of water was studied by the broad-line ~1H NMR technique at mixture storage times of 4, 8, and 12 months. It was shown that, during the mixture storage, the relaxation times of water decrease to the values indicating the loss of translational mobility, which is associated with the rearrangement of polymer network and an increase in the strength of hydrogen bonds in water. The molecular mobility of polymer network is exhibited at room temperature and disappears at 80 K. The water strongly bound by the system is incorporated into the forming crosslinked structure.