Different types of water in the film formation process of latex dispersions as detected by solid-state nuclear magnetic resonance spectroscopy

The properties of polymer films prepared from latex dispersions are influen ced by the drying or film formation process. In order to investigate this p rocess, various systems of aqueous latex dispersions were dried until a spe cific solid content was reached. The samples investigated were based on vin yl acetate, vinyl acetate/ethylene and pure acrylics employing different su rfactants and polyelectrolytes as stabilisers of the dispersions. The role of water in these partially dried films was investigated using H-1 and H-2 solid-state NMR spectroscopy. Different types of water could be distinguish ed in the spectra. The drying latex films were found to contain interfacial external water, water at ionic and nonionic groups at surfactants in the p olymer/water inter-face and also water inside the swollen polymer. These di fferent types of water were examined separately using Various NMR technique s.