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New classes of amphiphilic polyesters were prepared from metallated (Si, Ge) fatty methyl ester (FAME) precursors and poly(tetramethylene oxide) glycol. Hydrosilylation of 10-undecenoic methyl ester by tetramethyldisiloxane occurred at 80 degrees C in the presence of Karstedt's catalyst, and hydrogermylation of the same FAME derivative was obtained at the same temperature under radical AIBN initiation. These diester precursors, obtained in high yields (approximately 90%), reacted with poly(tetramethylene oxide) glycol under free solvent to give silicon polymers or germanium oligomers. These condensed materials display both the characteristic of organic-inorganic hybrid materials and those of amphiphilic polymers. The nature of organometallic fragment (hydrophobicity of tetramethyldisiloxy and sterical hindrance of diphenylgermyl) was shown to influence the chemical reactivity of the polymerizable monomers and the physical properties of the resulting copolymers. The amphiphilicity of these materials provides a driving force for the formation of small objects (approximately 1 nm), making them very attractive as hybrid nanocontainers.

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The miscibility behavior in blends containing poly(4-vinyl pyridine) (P4VPy) and poly(2-vinyl pyridine) (P2VPy) as polymer components and the dihydric phenols 4,4'-thiodiphenol (TDP) and 4,4'-methylendiphenol (MDP) as low molecular weight compounds (LMWC), was studied by Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared Spectrophotometry (FTIR) as main analytical techniques. The glass transition of P4VPy and the melting of TDP and MDP, were found to be significantly affected when the compounds were blended. This result was attributed to the miscibility between them, as a direct consequence of the specific interactions between the blend components. FTIR was used to investigate these interactions. The formation of intermolecular hydrogen bonds between the pyridine nitrogen atoms and the hydroxyl groups of TDP and MDP were discovered. When P2VPy was the macromolecular component, a difference was observed in the DSC behavior, which was attributed to a steric hindrance effect. Thermogravimetric and viscometry analysis were also used as additional techniques to complement the FTIR and DSC measurements performed.