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Advisor(s)
Abstract(s)
A novel fluorescent (p-phenylene ethynylene)-calix[4]arene-based polymer
(CALIX-PPE) has been successfully synthesized by cross-coupling polymerization of
bis-calix[4]arene 1 with 1,4-diethynylbenzene. The polycondensation was carried out
in toluene/NEt3 at 35 8C for 24 h, using PdCl2(PPh3)2/CuI as the catalytic system,
furnishing CALIX-PPE in excellent isolated yields (higher than 95%, several runs).
The yellow polymer is freely soluble in several nonprotic organic solvents. The GPC
trace of the isolated polymer showed a monomodal distribution and a number-average molecular weight of 23,300 g mol-1 (Mw/Mn¼ 2.05). No evidence was found in
the structural analysis (FTIR and 1H/13C NMR) regarding the formation of alkyne
homocoupled segments along the polymer chain. For comparative purposes, the syn-
thesis of an analogous poly(p-phenylene ethynylene) containing p-t-butyl-phenoxy-
methyl side chains (TBP-PPE) was also undertaken. A great similarity was found
between the photophysical properties of CALIX-PPE and TBP-PPE in solution
(UV–vis and laser induced luminescence), clearly demonstrating their unique de-
pendence on the structure and conformation of the conjugated PPE backbone. The
fluorescence spectra of polymers are of nearly identical shape, displaying their maxi-
mum emission around 420 nm. The calculated solution photoluminescence quantum
yields of CALIX-PPE and TBP-PPE are of similar magnitude (Ø/F(CALIX-PPE) = 0.43; Ø/F(TBP-PPE) = 0.51).
Description
Keywords
Bis-calix[4]arene Calixarene Conjugated polymers Fuorescence FT-IR GPC NMR p-phenylene ethynylene Synthesis
Citation
COSTA, Alexandra I.; FERREIRA, Luís F. V.; PRATA, José V. – Novel fluorescent (p-Phenylene ethynylene)-Calix[4]arene- based polymer: design, synthesis, and properties. Journal of Polimer Science Part A: Polymer Chemistry. ISSN 2642-4169. Vol. 46, N.º 19 (2008), pp. 6477-6488
Publisher
Wiley