Positive and negative ionochromism and UV sensor properties of oxygen-containing polysilanes

Abstract

Addition of lithium trifluoromethanesulfonate (LiOTf) to poly[(4-ethoxyethoxybutyl)octylsilylene] (PEBOS) prevents the normal thermochromic transition to longer wavelength (negative ionochromism), whereas addition LiOTf to poly[bis(5-ethoxyethoxypentyl)silylene] (PEEPS) induces a thermochromic transition (positive ionochromism); the latter effect is reversed in the presence of water or THF vapour, so that LiOTf-doped PEEPS serves as a UV sensor for H₂O or THF.