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Poly(propylene imine) dendrimers having 8, 32, and 64 primary amine end groups form diamino Cu(II), diamino Zn(II), and tetramino Co(III) complexes that are identified spectrophotometrically and titrimetrically. The dendrimer-metal ion complexes catalyze the hydrolysis of p-nitrophenyl diphenyl phosphate in zwitterionic buffer solutions at pH Յ 8.1 with relative activities Cu(II) Ͼ Zn(II) Ͼ Co(III). The rates of hydrolysis are faster with sodium perchlorate than with sodium chloride to control ionic strength. In sodium perchlorate solutions with Cu(II) the rates increase with increasing size of the dendrimer. In sodium chloride solutions with Cu(II) the rates decrease with increasing size of the dendrimer. Rate constants in buffered sodium chloride solutions of dendrimers and 1.0mM Cu(II) are 1.3-6.3 times faster than in the absence of Cu(II). The fastest hydrolyses occurred at a dendrimer primary amine to Cu(II) ratio NH 2 /Cu Յ 2. At NH 2 /Cu ϭ 4 and with the 1,4,7,10-tetraazacyclodecane complex of Cu(II) hydrolysis rates were much slower.

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Radiation crosslinked poly(ethylene oxide)s (PEO) modified with two tetraalkylammonium salts: allyldimethyldodecylammonium bromide and ethylmethacrylate dimethyldodecylammonium bromide were prepared. They have been characterized by elemental analysis, IR, 1H‐NMR spectra, and DSC measurements. Their activity as phase transfer catalysts (PTC) in the model displacement reaction of 1‐bromooctane with aqueous sodium cyanide were studied. The reaction kinetics were followed under pseudo‐first‐order conditions. Small amounts of onium salt inserted into the PEO network gave rise to a five time increase in the rate constant. The recovered catalysts could be re‐used without loss of activity. © 1995 John Wiley & Sons, Inc.