| abstract |
Energy efficient optoelectronic devices include an electroluminescent layer containing a polymer made up of structural units of formula I and II: wherein R1 and R2 are independently C22-44 hydrocarbyl, C22-44 hydrocarbyl containing one or more S, N, O, P, or Si atoms, oxaalkylaryl, or a combination thereof; R3 and R4 are independently H, C1-44 hydrocarbyl or C1-44 hydrocarbyl containing one or more S, N, O, P, or Si atoms, or R3 and R4, taken together, form a C2-10 monocyclic or bicyclic ring containing up to three S, N, O, P, or Si heteroatoms; and X is S, Se, or a combination thereof. |