Polymer Chemistry

Highly branched structures with a large number of functional groups of poly(amidoamine) (PAMAM) dendrimers and hyperbranched polymers make these materials very useful in many applications including host-guest encapsulation, nanoreactors, and delivery devices. We used both the advantages and limitations of A2 + B4 polycondensation method to make hyperbranched PAMAM hydrogel particles. Aqueous solution of hyperbranched PAMAM precursors was prepared by slow addition of A2 monomer, N,N’-methylenebisacrylamide, to aqueous solution of B4 monomer, ethylenediamine. And then the aqueous solution of hyperbranched PAMAM precursor was dispersed in a hydrophobic liquid and the A2 + B4 polycondensation proceeded until the critical gelation point. This simple method allowed us to make micro-sized hydrogel particles which wholly consisted of hyperbranched poly(amidoamine). The hyperbranched PAMAM hydrogel particles were found to be highly effective for the capturing of heavy metal ions from an aqueous solution and CO2.