1 research outputs found
Conjugated Polymer Nanoparticles by Suzuki–Miyaura Cross-Coupling Reactions in an Emulsion at Room Temperature
A range of stable emulsions of spherical
and rod-like conjugated
polymer nanoparticles (CPN) were synthesized via Suzuki−Miyaura
cross-coupling reactions of 9,9-dioctylfluorene-2,7-diboronic acid
bisÂ(1,3-propanediol) ester with a number of different dibromoarene
monomers in xylene, stabilized in water by the nonionic surfactant,
Triton X-102. High molar mass polyÂ(9,9-dioctylfluorene) (PF8), polyÂ(9,9-dioctylfluorene-<i>alt</i>-benzothiadiazole) (PF8BT), polyÂ(9,9-dioctylfluorene-<i>alt</i>-4-<i>sec</i>-butylphenyldiphenylamine) (PF8TAA)
and polyÂ(9,9-dioctylfluorene-<i>alt</i>-bithiophene) (PF8T2)
emulsions were obtained, at high overall conjugated polymer concentrations
(up to 11,000 ppm), in the presence of the palladium complex, (IPr*)ÂPdCl<sub>2</sub>(TEA) and base, tetraethylammonium hydroxide, in nitrogen
atmosphere at 30 °C after 24–48 h. TEM analysis of the
PF8 and PF8T2 emulsions revealed regular rod-like structures, up to
200 nm in length with aspect ratios of 4–5. PF8BT and PF8TAA
formed spherical particles with diameters of between 20–40
nm in TEM analysis. UV–vis absorption spectra of the PF8 emulsions
indicated high levels of ordered β-phase configuration (9–10%)
in their respective nanoparticles. Absolute photoluminescence quantum
yields (Φ) of 21–25% were recorded for these emulsions