Structure-property relations between silicon-containing polyimides and their carbon-containing counterparts

Abstract

The present paper examines silicon (Si)-containing polyimides and their structural carbon (C)-containing counterparts regarding the relation between their oxygen permeability on the one hand and their microscopic structure on the other hand. There are significant differences in the fractional free volume and the mean squared displacement of Si-containing polyimides and their carbon counterparts. Compared to the C-polyimides the Si-ones have a greater free volume and show more mobility in the side-groups while the C-ones have a higher mobility in the backbone. These differences are typically connected with higher oxygen permeabilities in the respective Si-containing polymers.