Synthesis of new star-shaped polymers with styrene-fluorene conjugated moieties and their multicolor luminescent ordered microporous films
Journal
Macromolecules
Journal Volume
43
Journal Issue
17
Pages
7151-7158
Date Issued
2010
Author(s)
Abstract
We report the synthesis, photophysical properties, and morphology of new star-shaped polymers with styrene−fluorene (St-Fl) conjugated moieties. Three polymers with different number of arms (P(St-Fl)n, n = 3, 4, and 8) were obtained by living anionic polymerization, and they exhibited a narrow molecular weight distribution (Mn/Mw <1.06). The effects of arm numbers, humidity, and solution concentration on the formation of the microporous structures were studied. It was found that the high molecular weight P(St-Fl)8 could form a highly ordered microporous film via drop-casting, but not on the polymers with the other two arm numbers. In addition, the pore diameter was reduced while enhancing solution concentration or decreasing humidity. Relatively uniform blue-emitting characteristics were obtained on the P(St-Fl)8 microporous films. Such highly ordered structure led to a red shift in photophysical properties, such as absorption and photoluminescence. Furthermore, green- and red-emission microporous films were obtained via blending a relatively small amount (∼1%) of poly((9,9-dioctylfluorenyl-2,7-diyl)-co-(1,4-benzo-(2,1′,3)-thiadiazole) or bis(1-phenylisoquinoline)(acetylacetonate)irdium(III) (Ir(piq)2(acac)) through efficient energy transfer. The experimental results suggested a new approach to synthesis of star-branched polymers with pendant conjugated moieties and the formation of the multicolor ordered microporous films.
SDGs
Type
journal article