SANS investigation of self-assembling dendrimers in organic solvents

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Pappannan Thiyagarajan, Fanwen Zeng, C. Y. Ku and Steven C. Zimmerman


Abstract

The self-assembly behaviour of tetraacids1ac and tetraester 4 in CDCl3 and [2H8 ]tetrahydrofuran {[2H8 ]THF} has been investigated by the small-angle neutron scattering (SANS) technique. The experimental SANS data were compared with simulated scattering data derived from structural models proposed previously for the aggregates. These studies suggest that dendritic monomers 1b,c self-assemble into cyclic hexameric aggregates, whereas 1a forms a large tubular aggregate in CDCl3 . Further study on 1c in CDCl3 as a function of concentration suggests that the cyclic hexameric aggregates strongly interact with each other at higher concentrations. The control compound 4 was shown to be monomeric in both solvents.


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