High Performance Amorphous Polymeric Thin-Film Transistors Based on Poly[(1,2-bis-(2′-thienyl)vinyl-5′,5′′-diyl)-alt-(9,9-dioctylfluorene-2,7-diyl] Se

ASAP Chem. Mater., ASAP Article, 10.1021/cm800447k

Synthesis and Characterization of the Electronic and Electrochemical Properties of Thienylenevinylene Oligomers with Multinanometer Dimensions

Soluble thienylenevinylene oligomers based on 3,4-dihexylthiophene with chain length approaching 100 Å (16-mer) have been synthesized. Optical data obtained in solution and on solution-processed thin films show that chain extension produces a narrowing of the HOMO-LUMO gap (E) and band gap (E_g) which reach values significantly smaller than that of the parent polymer. Plots of E and E_g vs the reciprocal number of carbons in the chain (1/Cn) reveal a deviation from linearity beyond the 10-12-mer suggesting a limit of convergence around the 20-22-mer. Cyclic voltammetry shows that chain lengthening induces a negative shift of the first redox potential, an increase of the number of accessible redox states, and a decrease of the Coulombic repulsion in multicationic species. Thus, the 16-mer can be charged up to the hexacationic state within a 0.60-V potential window. A plot of the potential of the various redox steps vs 1/Cn suggests full coalescence into a single-step process for the 20-22-mer. A single process is indeed observed for solution cast films of 16-mer, and the respective contributions of the intra- and intermolecular mechanisms in the recombination process are discussed.

J. Am. Chem. Soc., 120 (32), 8150 -8158, 1998.

Third-Order Nonlinear Optical Properties of Oligomers of Thienyleneethynylenes and Thienylenevinylene

J. Phys. Chem.; 1994; 98(40); 10102-10111.

Mark-Houwink-Sakurada Constants for the Methoxy Precursor of Poly(2,5-thienylenevinylene)

Macromolecules; 1995; 28(14); 5144-5146.

Absorption Properties of Alkoxy-Substituted Thienylene-Vinylene Oligomers as a Function of the Doping Level

In an attempt to improve on the properties of PEDOT (poly(3,4-ethylenedioxythiophene)) as a stable, conducting, and transparent coating we synthesized four different alkoxy-substituted poly(thienylene-vinylene)s, 1-4, using the Stille coupling reaction. The oligomers and polymers obtained were characterized and their NIR-vis absorption spectra were measured as a function of doping, both electrochemically as films and chemically in solution. Similar spectra of PEDOT films were gathered for comparison. In PEDOT a change in doping level does not change the energies of the absorption bands, while for the other polymers the bands shift markedly and the NIR peak at high doping level lies at a higher energy. The polymers 1-4 are much less suited for the intended coatings than PEDOT. Possible reasons for this are discussed.

Chem. Mater., 8 (3), 769 -776, 1996. cm9504551

Syntheses and Characterization of Electroactive and Photoactive 2,7-Carbazolenevinylene-Based Conjugated Oligomers and Polymers

Chem. Mater., 16 (23), 4619 -4626, 2004

Acyclic diene metathesis polymerization of 2,5-dialkyl-1,4-divinylbenzene with molybdenum or ruthenium catalysts: Factors affecting the precise synthe

J. Polym. Sci. A Polym. Chem. Vol.43, 23 Pages: 6166-6177

Poly(fluorenevinylene) derivatives by Heck coupling: Synthesis, photophysics, and electroluminescence

J. Polym. Sci. A Polym. Chem. Vol.44, 15 Pages: 4494-4507

Novel blue-greenish electroluminescent poly(fluorenevinylene-alt-dibenzothiophenevinylene)s and their model compounds

J. Polym. Sci. A Polym. Chem. Vol.44, 23 Pages: 6790-6800

Synthesis, Spectral Stability, and Electroluminescent Properties of Random Poly(2,7-fluorenylenevinylene-co-3,6-carbazolylenevinylene) Obtained by a S

The synthesis of a series of new random poly(9,9-dioctyl-2,7-fluorenylenevinylene-co-N-octyl-3,6-carbazolylenevinylene) copolymers at 20-80% mol/mol of carbazole (P2-P6) was achieved by a versatile Suzuki-Heck reaction cascade between the suitable dibromoaryl derivatives at different monomer ratios and potassium vinyltrifluoroborate. Their properties have been investigated by ¹H NMR, IR, TGA, DSC, cyclic voltammetry, UV-vis, and photoluminescence and compared to those of poly(9,9-dioctyl-2,7-fluorenylenevinylene) (P1) obtained by the same method. The control of the -conjugation extension and the inductive effects, determined by the amount of carbazolyl-3,6-ene moieties, permitted the modulation of the HOMO and LUMO energy levels of these materials without remarkably modifying their emission properties. Furthermore, different from poly(9,9-dioctylfluorene), a good spectral stability in the solid state was proven for P1 after a thermal annealing under air at 130 C. The electroluminescence properties of the materials were tested by constructing OLED devices of ITO/PEDOT-PSS/P1-P6/Ca/Al configuration. The improvement of the device performances for P2-P4 (20-50 mol/mol of carbazole) with respect to P1 was attributed to the better hole transport in the material because of the presence of carbazole units. The better performances of P5 (450 cd/m² at 22 V, 0.0225 cd/A at 22 V) were ascribed to the easier injection of electrons in the device with respect to the other copolymers, as a consequence of its higher electron affinity. These figures of merit could be improved by inserting a suitable electron injecting layer (Alq₃) between the cathode and P5 (890 cd/m² at 18 V, 0.0435 cd/A at 10 V).

Macromolecules, 40 (14), 4865 -4873, 2007.