| Abstract
| - Pulsed-field gradient NMR spectroscopy was used to study the diffusion of three differentpoly(propyleneimine) dendrimers with hydrophilic triethylenoxy methyl ether terminal groups (generations2, 4, and 5) in poly(vinyl alcohol) aqueous solutions and gels. The effects of the diffusant size, polymerconcentration (from 0 to 0.26 g/mL), and temperature on the self-diffusion coefficients have been studied,and the model of Petit et al. [Macromolecules1996, 29, 6031] was used to fit the experimental data. TheStokes−Einstein hard-sphere radii were also calculated in the zero concentration limit and were comparedwith those of the linear poly(ethylene glycol)s under the same conditions. The proton NMR relaxationtimes (T1 and T2) were measured to study the mobility of the dendrimer core part and terminal group asa function of the dendrimer size.
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