Low-bandgap polymers
Résumé
A conjugated copolymer absorbing at near IR region and exhibits a very low band gap between HOMO and LUMO comprises at least one repeating unit (I) (R' = C6-36 alkyl, M1 = heterocyclic rest) exhibits a very low band gap between HOMO and LUMO. Thus, a copolymer prepd. by copolymg. 24 h at 130° 0.4 mol dibromo-substituted (3E,7E)-3,7-bis(4-(2-decyltetradecyl)-4H-thieno[3,2-b]pyrrole-5,6dione)benzo[1,2-b:4,5-b']difuran-2,6(3H,7H)-dione and 0.4 mmol 4,4,-bis(2-ethyl-hexyl)-5,5,-bis(trimethyltin)-dithieno[3,2-b:2',3'-d]silol in the presence of tris(dibenzylideneacetone) dipalladium (0) and tri(o-tolyl)phosphine exhibits absorption max. 505 and 1,100 nm, HOMO -5.24 EV, LUMO -4.20 eV and band gap 0.86 eV.