A key feature of VPA is excellent metal ion complexation. VPA (co)polymers also exhibit this feature.
The interaction can be controlled by means of pH, but also depends on the charge and ionic strength of the metal ions.
In the case of VPA, the known high affinity of phosphonic acid to Cu, Ag, Co, Ni, Zn, Cd, Ca, Mg, Al and Cr metal ions [1,2] can be combined with polymerizability and therefore considerably expands the range of applications.
As VPA polymers interact superbly with metal ions and polar surfaces, they are eligible for application as dispersing agents or protective colloids, for example for inorganic particles.
[1] Rivas et al., Macromolecular Symposium 193, 237–250 (2003) [2] Ellis et al., Polymer International 24, 221–228 (1991)
