Electroluminescent SCPs

Copolymers 10 derived from 3,6-dibenzosilole and 2,7-fluorene are blue electroluminescent SCPs.27 When the copolymers are used as the emissive layer in EL devices, highly efficient pure blue emissions with CIE coordinates of (x = 0.16, y = 0.07), a 7EL of 3.34%, and a luminance efficiency of 2.02 cd/A at 326 cd/m2 are achieved from the copolymer with 90% fluorene content. The blue color matches the NTSC blue standard (x = 0.14, y = 0.08) quite well. The EL spectral stability of the devices is quite good, even under operation at elevated temperatures. Copolymer 9 derived from 3,6- and 2,7-dibenzosiloles also exhibits high performance with a jyEE of 1.95%, a luminous efficiency of 1.69 cd/A, and a maximal brightness of 6000 cd/m2, with the CIE coordinates of (x = 0.162, y = 0.084).26... 

Copolymers 11 derived from 2,7-fluorene and 2,3,4,5-tetraphenylsilole are green electroluminescent SCPs.28 The EL spectra of the copolymers show exclusive green emissions (AEL 528 nm) from the silole units, which are almost not changed with the copolymer compositions. A maximum 7yEL of 1.51% can be achieved with the copolymers as the emissive layer in EL devices. 

Copolymers 15 derived from 2,7-fluorene and 2,5-dithienylsilole are red electroluminescent SCPs.31 The EL devices with the copolymers as the emissive layer can display red light emissions with AEL up to 638 nm. The maximum //EL of the devices can reach 0.89%. Copolymer 18 derived from 2,7-fluorene and... 

The incorporation of siloles in polymers is of interest and importance in chemistry and functionalities. Some optoelectronic properties, impossible to obtain in silole small molecules, may be realized with silole-containing polymers (SCPs). The first synthesis of SCPs was reported in 1992.21 Since then, different types of SCPs, such as main chain type 7r-conjugated SCPs catenated through the aromatic carbon of a silole, main chain type cr-conjugated SCPs catenated through the silicon atom of a silole, SCPs with silole pendants, and hyperbranched or dendritic SCPs (Fig. 2), have been synthesized.10 In this chapter, the functionalities of SCPs, such as band gap, photoluminescence, electroluminescence, bulk-heterojunction solar cells, field effect transistors, aggregation-induced emission, chemosensors, conductivity, and optical limiting, are summarized. 

FIGURE 8. A SCP showing three-color white electroluminescence and its electroluminescent spectrum. 

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