Thiophene-based copolymers

Aside from investigating lyotropic liquid crystallinity in di-PA, our group also looked into thermotropic chiral liquid crystalline thiophene-based copolymers that exhibit red, green, and blue (RGB) CPL and white CPL [22]. 

Helically n-Stacked Thiophene-based Copolymers that Exhibit RGB and White Circularly Polarized Luminescence... 

K. Watanabe, I. Osaka, S. Yorozuya, K. Akagi, Helically n-stacked thiophene-based copolymers with circularly polarized fluorescence high dissymmetry factors enhanced by self-ordering in chiral nematic liquid crystal phase. Chem. Mater. 24, 1011-1024 (2012)... 

Thiophene-based copolymers incorporating the dioxide unit 29 have lower bandgaps than non-oxidized analogues (due to the increased electron affinity directed by the acceptor unit) and this feature could be... 

LEE 11] Lee S.-M., Lee S.-B., Kim K.-H. et al., Syntheses and photovoltaic properties of polymeric sensitizers using thiophene-based copolymer derivatives for dye-sensitized solar cells . Solar Energy Materials and Solar Cells, vol. 95, no. l,pp. 306-309,2011. 

A very efficient green-emitting fluorene copolymer 304 was synthesized by Shim and coworkers [390] via Suzuki coupling of dibromothieno[3,2-b]thiophene with dialkylfluorene-diboronic acid [390]. The authors compared the EL properties of this copolymer with PFO homopolymer 196 and PFO-bithiophene copolymer 295. Both the absorption and emission spectra of 304 are red-shifted compared with PFO 196 but slightly blue-shifted compared to bithiophene-based copolymer 295. PLEDs fabricated in the configuration ITO/ PEDOT/304/LiF/Al showed a pure green emission (CIE . v 0.29, r 0.63) close to the... 

B. Liu, W.-L. Yu, Y.-H. Lai, and W. Huang, Synthesis, characterization, and structure-property relationship of novel fluorene-thiophene-based conjugated copolymers, Macromolecules, 33 8945-8952, 2000. 

E. Lim, B. Jung, and H. Shim, Synthesis and characterization of a new light-emitting fluorene-thieno[3,2-6]thiophene-based conjugated copolymer, Macromolecules, 36 4288-4293, 2003. 

Random copolymers 596a-d synthesized by Yamamoto coupling of a fluorene and thiophene-base (02MI199 02MM1224). 

All the copolymers showed similar absorptions with Lmax at 470 nm, which was more intense for polymers with higher thiophene content. In contrast, their emission colors were progressively red shifted with increasing thiophene-based comonomer content. Copolymer 596a emitted bright red light (620 nm) with reasonably high photoluminescent quantum yields (34-69%). 

The synthesis, characterization, electrical conductivity, and field effect mobility of a series of novel soluble N-alkyl dithieno[3,2-b 2, 3 -d]pyrrole (DTP) and thiophene (TH)-based copolymers (DTP-co-THs) were reported (06MM1771 08JA13167). The incorporation of DTP units extends n conjugation, and the introduction of thiophene subunits imparts good solubility, high conductivity, and high charge carrier mobility. Therefore, the incorporation of DTP units and various substituted thiophenes into the polymer backbone affords the ability to enhance the solubility, lower the band gap, and achieve the enhanced electronic properties. 

FIGURE 3.1.14 Thiophene copolymers and non-thiophene-based polymers. 

Scheme 3 (a) The DHP-CPD photochemical interconversion (b) a DHP-based three-way switch (c) a thiophene-DHP copolymer capable of attenuating effective conjugation length via the DHP-CPD photochemical interconversion and (d) the two ji-circuits in a b enz annul ate d-DHP blue corresponds to the DHP skeleton, and red corresponds to a benzannulated aromatic. (View this art in color at... 

---