Polythiophene聚噻吩.docxVIP

Regioregular and Nonregioregular PolythiophenesContents1 Introduction2 Limitation and solutions3 Synthetic methods of poly (3-substituted thiophenes)3.1 Electrochemical polymerization3.2 Polycondensation 3.3 Oxidative coupling4 Regioregular polythiophene4.1 Stereoregularity4.2 Regioregularity5 Synthetic methods for regioregular polythiophene5.1 Polymerization of symmetrically disubstituted bithiophenes5.2 Transition metal catalyzed coupling polymerization6 Comparison of regioregular and nonregioregular polythiophenes6.1 NMR Spectroscopy6.1.1 1H-NMR6.1.2 13C-NMR6.2 Infrared spectroscopy6.3 UV-Vis-Near-IR-Spectroscopy6.4 X-ray Diffraction and Polarized Microscopy7 Applications8 References1. IntroductionSince the discovery of polyacetylene [1], which showed the ability of combining the properties of organic polymers and semiconductors, the era of conjugated polymers began.Polythiophene belongs to the poly(heterocycles) family , of which the structure is analogous to that of cis(CH)x is stabilized by the heteroatom[2]. Besides the common character of possessing conjugated pi system extending over a large number of recurrent monomer units, polythiophene is highly environmental stable in both its doped and undoped state and its structural versatility allows multiple modifications compared to polyacetylene ,thus it is of considerable interest from both theoretically and practically point of view. The structure of cis(CH)x, poly(heterocycles) and polythiophene is shown is figure 1.1: (a) (b) (c) (d)Figure 1.1: (a) cis(CH)x;(b)poly(heterocycles);(c)polythiophene;(d) more common representation of polythiophene.2. Limitations and solutionsFor some times ,the application of polythiophene has been limited due to its insolubility and infusibility, which can be attributed to its delocalized structure yielding stiff chain with strong inter-chain interactions and this is common for conjugated poly