Poly-3-octylthiophene films

The evolution of the XPS C(ls), S(2p), and Al(2p) core level lines, upon A1 deposition onto poly(3-octylthiophene) films (P30T), is shown in Figure 5-15 [84. The S(2p) spectrum for the pristine polymer consists of two components, S(2p 1/2) and S(2p.v2), due to spin-orbit coupling. 

ORIENTATION OF STRETCHED POLY(3-OCTYLTHIOPHENE) FILMS VISIBLE AND INFRARED DICHROISM STUDIES... 

Zhokhavets, U., G. Gobsch, H. Hoppe, and N.S. Sariciftci. 2005. A systematic study of the anisotropic optical properties of thin poly(3-octylthiophene)-films in dependence on growth parameters. Thin Solid Films 451 69. 

Kunugi, Y, Y. Elarima, K. Yamashita, N. Ohta, and S. Ito. 2000. Charge transport in a regioregular poly(3-octylthiophene) film. / Mater Chem 10 2673. 

R. Singh, J. Kumar, R. K. Singh, A. Kaur, K. N. Sood and R. C. Rastogi. Effect of thermal annealing on surface morphology and physical properties of poly(3-octylthiophene) films. Polymer 46(21), 9126-9132 (2005). 

Tolstopyatova EG, Sazonova SN, Malev VV (2005) Electrochemical impedance spectroscopy of poly(3-methylthiophene) and poly(3-octylthiophene) film electrodes. Electrochim Acta 50 1565-1571... 

Deen, M. Kazemeini, M. 2005. Photosensitive polymer thin-film FETs based on poly(3-octylthiophene). Proc. IEEE 93 1312-1320. 

FIGURE 5.2.4 Two-dimensional GIXD patterns of drop-cast HT-PAT films with different aUcyl side-chain lengths (a) PHT (b) poly(3-octylthiophene) (POT) (c) poly(3-dodecyl thiophene) (PDDT). (From Yang, H. unpuhhshed data, 2006. With permission.)... 

Thin films of poly(3-hexylthiophene-2,5-diyl) and poly(3-octylthiophene-2,5-diyl) mixed with two electron-accepting polyquinolines [159] show quenching of the steady-state photoluminescence and a shortening of the fluorescence lifetime of the polyquinolines, suggesting photoinduced electron transfer from polythiophene to polyquinoline at the polyquinoline/polythiophene interface. A new, weak and red-shifted emission band centered at 630 nm and reduced lifetimes show the formation of intermolecular exciplexes at the polyquinoline/polythiophene interface. Exciton diffusion lengths in the polyquinolines have been estimated to be 17-22 nm. 

S.H.M. Persson, P. Dyreklev, and O. Inganas, Patterning of poly(3-octylthiophene) conducting polymer films by electron beam exposure, Adv. Mater., 8,405-408 (1996). 

Poly(3-octylthiophene) (P30T) was prepared by the method described elsewhere [10], utilizing FeCl3 as a catalyst. P30T was used in two configurations (a) free- standing film the film thickness after stretching was around 2 [xm (b) film spun on a polyethylene (PE) foil. 

Poly(3-octylthiophene) has been oriented, by stretching a free-standing film and by stretching a sandwich structure, polyethylene/poly(3-octylthiophene). The infrared dichroism studies indicate that P30T is higWy oriented at a rather low draw ratio ... 

In polyaniline-cellulose acetate films, phthalate and phosphate plasticizers were used. The addition of the plasticizer increases film flexibihty and lowers percolation threshold. It can be seen by ophcal microscopy that polyaniline grain sizes are reduced. Similar principle was adopted in polymer blend of thermoplastic polymer and polya-niline. Various plasticizers and their concentrahons were used to partially compatibilize blend in such a maimer that it still has domains of different conductivities but a low percolation threshold. Polyvinylchloride and poly(3-octylthiophene) are iimniscible but there is a low interfacial tension which allows to produce co-conhnuous morphology responsible for increased conductivity of blends along with increase in poly(3-octylthiophene) con-centrahon. Addition of DOP to this blend increases its conduchvity even if the concentration of poly(3-octylthiophene) decreases. 

Erb, T, S. Raleva, U. Zhokhavets, G. Gobsch, B. Stuhn, M. Spode, and O. Ambacher. 2004. Structural and optical properties of both pure poly(3-octylthiophene) (P30T) and P30T/fiillerene films. Thin Solid Films 450 97. 

Poly(67), which is a low-gap material, has been used for the construction of a display in which the polymer acts as both anode and cathode [332]. Electrochromic devices using solid electrolytes have been prepared. One of them consists of poly(3-octylthiophene) or PP films with vanadium oxide as the counterelectrode and poly(ethyleneoxide) as the solid electrolyte [333]. However, the performances of these devices is low, reaching a maximum of 100-cycle operation, due to the instability of the polymers and the high operating temperatures. Much better results have been obtained with poly(EDOT). An electrochromic device based on this material and poly(ethylene oxide)-poly(phosphazene) as the solid electrolyte has been proposed [334] it may operate up to 1000 cycles without losses. 

The same electrochemical ion exchange process makes the polymer change its volume, so that polymer films shrink and swell following oxidation and reduction. This property suggested their use as actuators. In fact if poly(3-octylthiophene) [344] and PP [345] are electrodeposited onto a gold-coated polyethylene strip, redox switching induces bending of the strip. 

Electrochromic devices using solid electrolytes have been produced more recently. A device [425] is based on poly(3-octylthiophene) or polypyrrole films with vanadium oxide as a counter-material and poly(ethylen-oxide) as a solid electrolyte. The poor performances (maximum 100 cycles of operation) of these early devices, due to the instability of the materials and the high operating temperature, have been greatly improved by the use of poly(3,4-ethylenedioxythiophene), provided with a low oxidation potential and optimum contrast, and of a poly(ethylenoxide)-poly(phospha-zene) solid electrolyte of high room temperature conductivity [153]. This device may be operated up to 1000 cycles without losses. 

---