Hyperbranched polyethyleneimine architecture onto poly(allylamine) by simple synthetic approach and the chelating characters

In resemblance to the ethoxylation of alkylamine or polymeric amines to introduce the nonionic hydrophiles by incorporation of ethylene oxide groups to make surfactants, ethyleneimine (EI) groups were introduced into poly(allylamine) by a simple in situ reaction of this polymer with 2-chloroethylamine hydrochloride. The resultant polymers were allylic and chain-pendant with hyperbranched polyethyleneimine. The EI number (n) of the polymers was determined by ¹H NMR. The percentages of primary, secondary, and tertiary amine present were estimated by potentiometric titration. The chelating abilities of the polymers that were applied growth conditions once (G₁, n ≈ 2) and twice (G₂, n ≈ 6) were also examined by potentiometric titration and ultraviolet-visible spectroscopy in the presence of metal ions (Cu⁺²). Continuous-variation analysis revealed that each repeat unit of G₁ and G₂ behaves as a multident chelate and forms a stable complex with Cu⁺² ions utilizing an average of three EI dents per ion.