Charge-transporting polymers structural derivation

Secondly, we describe the site-selective introduction of a functional molecule, tetrakis-5,10,15,20-(4-carboxyphenyl)porphyrin (TCPP), into the microphase separation structure of a diblock copolymer film of PS-fo-P4VP. Since porphyrin derivatives show various functionalities such as sensitization, redox activity, and nonlinear optical effect, a polymer nanodot array containing a porphyrin at a high concentration would be applicable to a light-harvesing and charge transporting nanochannel. 

The polymers used in this chapter are all polyfluorene derivatives. They are ABAB copolymers with A being the fluorene group shown in Fig. 2.4(a). Due to their high chemical stability, flexible chemistry and good charge transport and luminescence properties, polyfluorenes are very common materials for polymer optoelectronics and have been used to make highly efficient LEDs [26, 13] as well as good photovoltaic diodes [27, 28] and transistors [29]. Table 2.1 lists the abbreviated and full names of all the polymers that appear in this chapter. The chemical structures of each of the polymers are displayed in Fig. 2.4. 

After fundamental stupes on soluble RO-PPV derivatives(9), we have focused on the synthesis of highly luminous polymers and fabrication of highly efficient devices to commercialize P-LED. Taking exciton confinement and charge transporting into account, we have copolymerized various kinds of arylene vinylene units to introduce structural and energetic irregularity into poly(arylene vinylene). 

The highest mobilities achieved in solution-deposited polymer transistor devices have been exhibited by thiophene-containing polymers. Thiophene is an electron-rich, planar aromatic heterocycle, which can form a range of conjugated polymers when coupled appropriately [23, 24], The crystalline nature of many thiophene derivatives plays a role in their excellent charge transport properties. In this chapter, we will focus on copolymers of thiophene with the fused unit, thienothiophene, and their structural analogues. 

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