| A series of Poly (ester-amine) dendrimers were synthesized, characterized and functionalized. Properties of dendrimers and functional dendrimers were studied, and some dendrimers were tried for functional materials.SYNTHESIS OF DENDRIMERS:For the first time. Poly (ester-amine) dendrimers with ethylene diamine (EDA) or trimethylolpropane triacrylate (TMPTA) as a core, acrylate or amino as a terminal group were synthesized from TMPTA (three functional groups) and EDA (four functional groups) by Michael addition reaction. The reactions were carried out under mild conditions to give dendrimers in moderate yields. The by-reactions were suppressed by use of excess branching monomers.In the synthesis, only one atomic economical reaction (Michael addition reaction) was employed. Two monomers reacted alternatively without protect-deprotect steps so that each step reaction made the dendrimers grow efficiently. The terminal acrylate group and amino grew rapidly in turn because both of the monomers contained multifunctional groups. For example, there were 48 terminal acrylate groups on the periphery of the second-generation dendrimer with EDA as a core and TMPTA as a branching monomer. Both acrylate and amino could be easily changed into other functional groups. Therefore, dendrimers with peripheral acrylate and amino could be easily further functionalized.SEPARATION OF DENDRIMERS:The dendrimer Gl.O (NH2)3 (with TMPTA core and amino terminal group), Gl.O (acrylate)8 (with EDA core and acrylate terminal-group), and G1.5 (NH2)g (with EDA core and amino terminal group) could be separated and purified by extraction with solvents. This separation method was simple and could get products with high purities.FUNCTIONALIZATION OF DENDRIMERS:HydrOXylation: Gl.O (acrylate)8 was hydroxylated with diethanolamine (DBA) by Michael addition reaction under mild reaction conditions to form hydroxyl terminated dendrimers Gl.O (OH)i6 which could be separated in a quantitative yield and high purity by removal of methanol after the reaction had finished.Sulfonation: Sulfonation of 8 acrylate double bonds on the periphery of Gl.O (acrylate)g with NaHSCb was carried out in organic mixture solvent of diglycol and 2-butanone under normal pressure. The sulfonafe sodium-terminated dendrimer Gl.O (SOaNaJg was successfully isolated easily.CHARACTERIZATION OF DENDRIMERS:The structures of dendrimers and their functional products were characterized by FTIR, 'H NMR, I3C NMR, elemental analysis, HPLC and ESI-MS.PROPERTIES AND APPLICATION OF DENDRIMERS:Performance of water-soluble dendrimers in solution: Water-solubledendrimers Gl.O (NH2)3, G1.5 (NH2)g, Gl.O (OH)i6 and Gl.O (SO3Na)8 acted as surfactants. The surface tension of their water solutions was lower than that of polyethylene glycol (PEG) aqueous with the same concentration. When the concentration of aqueous increased, the surface tension of Gl.O (NHi^, G1.5 (NH2)s and PEG aqueous gradually decreased, while the surface tension of Gl.O (OH)i6 and Gl.O (SO^Na^ aqueous greatly decreased at first, then gradually tended to stable.Gl.O (SO3Na)g dendrimer was a polyelectrolyte with unique properties. Its aqueous appeared as dilatant fluid. The viscosity of 1.0% ?.0% aqueous was almost no change in the range of PH value from 1.5 to 12.0, and electric conductivity of the aqueous changed very little from the PH value 3.0 to 10.0, which indicated that Gl.O (SO3Na)g could be applied in the wide range of pH value.The effect of concentration on the viscosity of Gl.O (SC>3Na)g aqueous was similar to that of NaCl aqueous, while the effect of concentration on electric conductivity of Gl.O(SO3Na)g aqueous was similar to that of Alginate sodium. Gl.O (SO3Na)g could form global aggregates in water.Interaction of water-soluble dendrimers with metal ion: in dilute aqueous,Gl.O (OH),6 and Gl.O (SO3Na)8 dendrimers interacted with Ag+, Cu2+, Fe2+ by intermolecular force or electrostatic attraction, leading to stable dendrimer / metal ions composites which was the basis o...
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