Gas-phase pyrolysis of biscyclopentadienyl zirconium dichloride

Volatility and thermal stability of biscyclopentadienyl zirconium dichloride Cp2ZrCl2 in gas phase have been studied. The vapour-condensed phase equilibrium in the processes of sublimation and evaporation is considered. Temperature dependence of Cp2ZrCl2 saturated vapour pressure above solid phase and melt has been defined. Kinetic and activation parameters of Cp2ZrCl2 pyrolysis are determined. Analysis of volatile products of pyrolysis at different degree of reagent transformation is carried out. It is shown that Cp2ZrCl2 decomposition occurs via break of zirconium-cyclopentadienyl bond and partial splitting of the bond inside five-member ring. 5 refs., 2 tabs