A series of condensation polymers (polyesters and polyamides) of ferrocene and siloxane derivatives have been synthesized and characterized. Thus, 1,1′-di(chlorocarbonyl)ferrocene (CAFc) and four different siloxane derivativess1,3-bis(aminopropyl)tetramethyldisiloxane) (AP 0 ), R,ω-bis(3-aminopropyl)oligodimethylsiloxane (AP), 1,3-bis(hydroxypropyl)tetramethyldisiloxane (HP 0 ), and 1,3-bis(p-hydroxyphenyleneazomethine-3-propyl)tetramethyldisiloxane (HBS 0 )swere used as monomers for this purpose. A model polyamide was prepared by polycondensation of oxalyl chloride with AP 0 . This was analyzed as such or doped with ferrocene in order to appreciate the influence of the ferrocene units by comparison with the corresponding copolymer containing chemically linked ferrocene in the main chain. Thermal, mesomorphic, viscometric, and solubility behaviors of the obtained compounds were studied. Molecular masses were estimated by GPC. The polymers were investigated by cyclic voltammetry and UV-vis absorption spectroscopy in order to evaluate the redox properties and photochemical behavior.

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A high molecular weight dimethylmethylvinylsiloxane copolymer (Mv = 450, 000) has been synthesized, analyzed, and used as matrix to prepare a composite by mixing with a proper amount of silica. A mixture of Fe2O 3/TiO2 was added to obtain a color close to the natural. 2,4-Dichlorobenzoyl peroxide was also incorporated as a crosslinking catalyst. This heat curable silicone-based formulation was used for relining removable dental prosthesis. The optimum conditions to appliance and hardening of the silicone composite on the prosthesis were established. The main surface (morphology, water contact angle, and water vapor sorption capacity) and mechanical characteristics were evaluated for the crosslinked silicone processed as thick film. The prosthesis relined with silicone was tested on a machine simulating mandible biomechanics both from kinematics and dynamic points of view. The results revealed a good behavior of our composite that remained unmodified after 700,000 mastication cycles.

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A series of composites based on polydimethylsiloxane-a,x-diol (PDMS) as polymeric matrix, silica aerogel as reinforcing filler, and the lignin powder-a biomass derivative, as bulking filler, have been prepared. Different weight ratios between components were used. The composites were investigated by scanning electron microscopy, dynamic mechanical analysis, tensile strength tests, X-ray diffraction analysis, thermogravimetric analysis, and differential scanning calorimetry. The results were compared with those obtained on a reference sample prepared by using a classical material-diatomite and a pure crosslinked PDMS.