Water adsorption on and desorption from crystalline copolymers of vinylidene fluoride with trifluoroethylene.

ABSTRACT

Water adsorption and absorption on crystalline polyvinylidene fluoride with 30% trifluoroethylene, P(VDF-TrFE, 7030), was examined by thermal desorption spectroscopy. Two distinctly different water adsorption sites are identified one adsorbed species that resembles ice and another species that interacts more strongly with the polymer thin film. The existence of the latter species is consistent with X-ray diffraction studies of water absorbed into the bulk of copolymers of polyvinylidene fluoride with trifluoroethylene crystalline thin films. There are strong steric effects observed in the angle-resolved thermal desorption that may be a result of the large polymer thin film surface dipoles.