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Carbohydrate-modified cyclosiloxanes were synthesized by hydrosilylation reactions of protected allyl-monosaccharides and subsequent deprotection with a gel-type ion exchanger. They were characterized by 1 H and 13 C-NMR, FT-IR, GPC and surface tension measurements. These compounds, as well as other water soluble, carboxylate-based siloxanes were tested as stabilizers in nanoparticle formulations, with polydimethylsiloxane (PDMS), poly(ε-caprolactone) (PCL) and UDEL polysulfone (PSF) as polymer cores. Owing to their low critical micelle concentrations (cmc), small amounts of surfactants were required. The particle size and granulometric distribution were measured by dynamic light scattering (DLS). Electron microscopy confirmed the DLS results and revealed aggregation phenomena in dry state, depending on the polymer core. In the tested conditions, the glass transition temperature of the polymer seems to be the driving force for the stability of dry nanoparticles.

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A polydimethylsiloxane‐α,ω‐diol with molar mass Mn = 43,000 has been synthesized by cationic polymerization of octamethylcyclotetrasiloxane and reinforced with silica. Two pathways were used for incorporation of silica in the polymeric matrix: ex situ by mechanical blending of a pretreated fumed silica and in situ by adding tetraethyl‐orthosilicate (TEOS) as silica precursor in the polymer matrix followed by their hydrolysis and condensation (sol–gel technique). The procedure occurred in the absence of solvent. Composites with different contents of silica were prepared and investigated by dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). The results were compared to those obtained on a model network based on the same polysiloxane without silica. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers