Dielectric investigation of the molecular mobility of silicone ladder polymers

Dielectric spectroscopy has been used to study the molecular mobility in polyphenylsilsesquioxane, polyphenylisobutylsilsesquioxane with a 1:1 ratio of phenyl to isobutyl groups, and poly-m-chlorophenylsilsequioxane on the temperature interval from −196 to 300°C at frequencies from 102 to 106 Hz. The investigation was carried out in air and in a nitrogen atmosphere. The flexibility mechanism of silicone ladder polymers is considered and the development of molecular mobility is shown to be discrete.