Silicone-Polyoxometalate (SiPOM) Hybrid Compounds

Oligomeric and polymeric SiPOM materials have been prepared by reacting trichloro endblocked PDMS [degree of polymerization, ∼ 14 (I) and 60 (II)] with α-K 8 SiW 11 O 39 . NMR and IR spectroscopy show that the POM units are bonded to the siloxane via Si-O-W bonds. The reaction of the short PDMS segment (I) with the POM produces powdery materials, (isolated as tetrabutylammonium salts) while the longer PDMS (II) forms elastomeric materials. For the latter the POM anions act as reinforcing fillers. Other important properties of the hybrid materials are their UV absorbency, their electrochromicity, their electrical properties (volume resistivity, ∼10 11 ohm-cm; low loss tangent, memory capability) and their film formation.