POSITIVE AND NEGATIVE IONOCHROMISM AND UV SENSOR PROPERTIES OF OXYGEN-CONTAINING POLYSILANES

Addition of lithium trifluoromethanesulfonate (LiOTf) to poly[(4-ethox yethoxybutyl)octylsilylene] (PEBOS) prevents the normal thermochromic transition to longer wavelength (negative ionochromism), whereas addit ion 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-dope d PEEPS serves as a UV sensor for H2O or THF.