| Abstract
| - A new family of polysilsesquioxanes colloids was synthesized by hydrolytic condensation of a functionalizedprecursor N-(6-aminohexyl)aminopropyltrimethoxysilane (AHAPS), H2N(CH2)6NHCH2CH2CH2Si(OCH3)3,and studied using small-angle X-ray scattering, transmission electron microscopy, liquid and solid stateNMR, elemental analysis, and other methods. The PAHAPS (polymerized AHAPS) structure is highlyfunctionalized and its functionality can be varied by protonation of the amino groups. This allows varyingthe local ordering in the PAHAPS colloids, including formation of highly ordered lamellar structures whenthe AHAPS precursor is hydrolyzed in pure water. By varying the type of solvent (water or THF), one canvary the macrostructure and properties (for example, to impart colloidal solubility) of PAHAPS. Thesefeatures make PAHAPS a robust polymer material synthesized in a one-pot reaction procedure. As aminogroups (protonated or not) easily interact with the majority of transition-metal compounds, PAHAPScolloids can template a variety of particles of interest: magnetic, semiconductor, metal, or metal oxideswith a small variation in the synthetic procedure. Here, formation of narrowly distributed discrete Ptnanoparticles packed within PAHAPS colloids (Pt content reaching 36 wt % without particle agglomeration)is described. The dependence of Pt nanoparticle and PAHAPS colloid sizes on metal compound and reducingagent types is demonstrated.
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