Effects of emulsification on properties of quaternary ammonium ion-based polyurethane anionomer

Abstract

Quaternary ammonium ion-based Polyether polyurethane anionomer solution and emulsion are studied. In the un-ionized film, the soft segment crystallites are not present. Ionization creates soft segment crystallites and produces increased phase separation between the soft and hard domains, which leads to an increase in both tensile strength and elongation at break. Emulsification of the PU ionomer solution can lead to slightly increased phase mixing. During the emulsification, conductivity and viscosity variations show that water is first adsorbed on the surface of the hard-segment microionic lattices and then enters successively into the more disordered and less disordered hard domains. The morphology of the unionized film shows that the hard domains are dispersed in the soft domains and that the size of hard domain increases greatly after the ionization. After dispersion, the hard segments originally distributed in the dispersed phase can be inverted to become a hard domain network.