Flexible and homogeneous inorganic/organic hybrid sheets were fabricated from silanol-terminated polydimethyldiphenylsiloxane (PDMDPS), phenyltriethoxysilane (PhSi(OEt)₃) and chemically modified zirconium n-butoxide (Zr(OBuⁿ)₄). Fourier transform infrared (FT-IR) spectroscopic, nuclear magnetic resonance (NMR) spectroscopic and differential scanning calorimetric (DSC) studies revealed that species derived from PhSi(OEt)₃ and Zr(OBuⁿ)₄ reacted with the silanol-terminated end groups of PDMDPS chains and connected each PDMDPS chains as a cross-linkage agent. Monophenylsiloxane species derived from PhSi(OEt)₃ were also found to act as an inhibitor of the micro-Brownian of PDMDPS chains and affect the mechanical properties such as the tensile strength and elongation. Thermogravimetric and differential thermal (TG-DTA) analysis revealed that the thermal decomposition occurred above 400°C, which was higher than that of PDMS-based inorganic/organic hybrids. The addition of FeCl₃ was not remarkably effective in thermal stabilization but affected both tensile strength and elongation to fracture.