Poly(p-xylene tetrahydrothiophenium chloride) doped photoluminescent sol-gel composite

Abstract

Poly(p-xylene tetrahydrothiophenium chloride), a polyphenylene vinylene (PPV) precursor in water and sol-gel solution has been used to prepare photoluminescent glass and coatings. Lactic acid-tetramethoxysilane and lactic acid-aminopropyltriethoxysilane sol solutions were doped with 0.02–0.47 wt% PPV precursor solution (2.5 g/dm³). The visible light emission from vacuum dried doped sol coating, at 365 nm excitation is about four times brighter than pure uncured PPV precursor film. A 23 mg of lactic acid-aminopropyltriethoxysilane sol containing 31 μ g PPV precursor, coated on glass slide gave an emission of 286 Cd/m². The brightness increases with dopant concentration and is stable on heating to 130^∘C. The brightness decreases to 27 Cd/m² at 190^∘C due to coversion of poly(p-xylene tetrahydrothiophenium chloride) to PPV. The bright emission from doped composite is due to wave guiding of sol, transparency of the polymer in the matrix, and the morphology of the composite. The nonlinear optical properties of this material may be useful in display technology and optoelectronics and when coated on glass convert UV radiation to visible light.