Polyurea Materials and Their Environmental Applications

With the rapid economy development, environmental pollution becomes an urgent issue. Porous polymer materials have been a main player to this issue because their structures are easy to be designed to address these issues. Here we present different protocols for preparations of a variety of polyureas (PU), all through polymerization of a diisocyanate with a diamine in aqueous phase, added in water or in-situ formed from the reaction of water with the diisocyanate involved. Two PU materials of different types are discussed in this study: (1), PU under form of microspheres was prepared through precipitation polymerization using isophorone diisocyanate as the monomer in a mixed solvent of water-acetonitrile. Aldehyde groups were attached to the surface of the PU microspheres. Immobilized of an enzyme, laccase, was carried out. The immobilized enzyme was used as biocatalyst in the process of degradation of organic dyes, and demonstrated high performance with good reusability. (2), porous PU (PPU) was also prepared through precipitation polymerization of toluene diisocyanate with a diamine or via the reaction of water. PPU was used directly to adsorb organic dyes and metal ions from aqueous systems with high performance and high selectivity. (paper)