Poly-2,8-indenofluorene

S. Setayesh, D. Marsitzky, and K. Mullen, Bridging the gap between polyfluorene and ladder-poly-p-phenylene synthesis and characterization of poly-2,8-indenofluorene, Macromolecules, 33 2016-2020, 2000. 

D. Marsitzky, J.C. Scott, J.-P. Chen, V.Y. Lee, R.D. Miller, S. Setayesh, and K. Mullen, Poly-2,8-(indenofluorene-co-anthracene) — a colorfast blue-light-emitting random copolymer, Adv. Mater., 13 1096-1099, 2001. 

An intermediate structure between PPP and polyfluorene has been developed, the poly(2,8-indenofluorene). This blue emitting polymer is stable up to 380°C, and shows thermotropic LC behavior at high temperatures (250-300°C) making it a good candidate as the active material in polarized LEDs [278]. 

FIGURE 1.15 Chemical structure of polylfluorene) (PF) and poly(indenofluorene) (PIF). R is either a linear or a branched alkyl chain or bulkier groups such as butoxyphenyl (BP) or triphenylamine (TPA). For PIF, R is either... 

The conclusions drawn on the packing of PF chains can be extended to a parent polymer, poly (indenofluorene) (PIF see Figure 1.15). Indeed, thin deposits of n-octyl-substituted PIF (OPIF) show fibrillar patterns very similar to those observed for the other polymers in the series (Figure 1.23a). This suggests that the packing of the PIF chains is similar to that proposed for the poly(fluorene) chains. 

FIGURE 1.40 Molecular structure of R,o-bis(Ai-(2,6-diisopropylphenyl)-l,6-bis-(4-tert-butylphenoxy)-3,4-dicarbonicacidimide-9-perylene-poly-2,8-(6,6,-12,12-tetraethylhexyl) indenofluorene (PEC-PIFTEH). 

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