X-ray diffraction and positron annihilation life-time spectroscopy studies of polymetalloorganosiloxanes

Resumo

X-ray diffractometry and positron annihilation life-time spectroscopy are applied to study the structural features of polymetallophenylsiloxane (PMOS) samples with the Si/M ratio corresponding to the metal valence state, namely, interplanar spacings (d₀₀₁), coherentscattering region (CSR) sizes, cross-section areas of polymer chains (s) calculated by the Miller-Boyer method, and the degree of amorphousness (β). It is demonstrated that the direct proportional dependence between the logarithm of the interplanar spacing d₀₀₁ and the logarithm of the cross-section area s is observed for PMOSs. This is an inverse dependence relative to changes in the crystal chemical ion radius. The extraction of the iron ion from polyferrophenylsiloxane leads to a sharp decrease in the interplanar spacing, which turns out to be less than d₀₀₁ in polyphenylsiloxanes, and also CSR increases due to a decrease in the diameter of the polymer chain. The positron annihilation life-time spectroscopy data show the observed direct dependence of the annihilation intensity (I₃), the annihilation rate (K₃), the degree of amorphousness on the PMOS cross-section area.