Impact of Water on the Miscibility of DAB-dendr-(NH₂)₆₄ and Benzene

The miscibility of the fifth-generation 1,4-diaminobutane poly(propyleneimine) (DAB-PPI) dendrimer and benzene was investigated. The liquid−liquid phase transitions in mixtures containing from 0.02 to 0.26 weight fraction of the dendrimer were determined. It was shown that the miscibility of the dendrimer and benzene depend to a great extent on the water content in the system. The binary system dry dendrimer + dry benzene does not show a liquid−liquid phase split. The addition of small amounts of water (as small as 0.06 wt %) to the system induces complex phase behavior. The liquid−liquid phase transitions in the ternary systems DAB-PPI dendrimer + benzene + water (0.06 wt %) are accompanied by unusual changes in the properties of the coexisting phases. The influence of water on the ¹H NMR spectra of the fifth-generation DAB-PPI dendrimer dissolved in benzene was also investigated.