New silica-based hybrid materials (Nouveaux matériaux hybrides à base de silicium)

GRAPHICAL ABSTRACT

ABSTRACT

New hybrid organic-inorganic materials have been obtained by reactions at room temperature of polymethylhydrosiloxane (PMHS) with different organic bi-functional molecules, in tetrahydrofuran (THF) using hexachloroplatinic acid (H₂PtCl₆.6H₂O) as a catalyst. These reactions have led to the formation of monolithic colored and transparent polymeric gels. The characterization of xerogels has been carried by infrared, ²⁹Si and ¹³C CP MAS NMR and thermal analysis DTA-TGA. Xerogels morphology and texture were studied by scanning electron microscopy (SEM) and Brunauer–Emmet–Teller method (BET). The obtained results show that organic molecules react with PMHS leading to gels in which Si–N and Si–O covalent bridges are formed. The optic and magnetic properties of hybrid gels are studied respectively by UV-Vis spectroscopy and RPE. The obtained results show that materials are paramagnetic semiconductors.

KEYWORDS:

• Hybrid materials
• ²⁹Si and ¹³C CP MAS-NMR
• SEM, UV-vis and RPE