Low bandgap polymers from fused dithiophene diester

Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Polymers from only ethylenic monomers or processes of...

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

528377, C08G 7500

Patent

active

055104380

DESCRIPTION:

BRIEF SUMMARY
BACKGROUND OF THE INVENTION

Since the discovery of high electrical conductivity in "doped" polyacetylene films in the mid-1970's, the field of electroactive polymers has undergone explosive growth. The great interest in these materials stems from their potential use in electronic and optical applications. Electrical conductivity is typically achieved via oxidative (or, more rarely, reductive) doping of the neutral polymers, a practice which is often accompanied by reduced processibility and environmental stability. Hence a major goal in this field is the design and synthesis of processible polymers with low or zero bandgaps.
The potential benefits from such low gap polymers are well recognized and recent theoretical approaches have focused on bond length alternation (Bredas, et al., 1986; Toussaint, et al., 1989-2; Toussaint, et al., 1989-1; Bredas, J. L., 1985; Bakhashi, et al., 1987; Bredas, J. L., 1987; Kertesz, et al., 1987; Hanack, et al., 1991) and variations in occupancy of frontier orbitals (Tanaka, et al., 1985; Tanaka, et al., 1987; Tanaka, et al., 1989; Tanaka, et al., 1988) to identify likely low E.sub.gap systems. Polyisothianaphthene (PITN) (Wudl et al., 1984), I, and its derivatives (Ikenone et al., 1984), with E.sub.gap .apprxeq.1.1 eV represent some of the more successful experimental realizations of these theoretical predictions (Colaneri, et al., 1986; Kobayashi, et al., 1985). These polymers have E.sub.gap 's 1 eV lower than their corresponding parent, polythiophene, (PT) (Bredas, J. L., 1985). This reduction in E.sub.gap is ascribed (Bredas et al., 1986) to an increased contribution of the quinoid structure, brought about by the 3,4-fused benzene ring. Thus, a considerable amount of the effort to date on narrow band gap polymers has concentrated on increasing their quinoid character. (See FIG. 1).
The energy difference between the aromatic and quinoid structure varies depending on the neutral material's degree of aromaticity. For polymers like polyphenylene, polythiophene, and polypyrrole, it can be substantial so that very little of the quinoid resonance form contributes to the neutral polymer's overall structure. Quinoid segments can be generated in these polymers by the doping process (Bredas, et al., 1984; Bredas, et al., 1982), however, and their growth followed by optical spectroscopy (Chung, et al., 1984). The energy dissimilarity is reduced in PITN since the creation of the quinoid structure in the thiophene moiety is partially compensated by return of aromaticity to the fused six membered ring. This observation has led to several other approaches for generating stable quinoid character. One (Toussaint, et al., 1989) is exemplified by structures like poly(2,7-pyrenylene vinylene), as shown in FIG. 2, structure IIa, to achieve the quinoid resonance form since in doing it exchanges one formally aromatic structure for another (bold outline).
Hence polymer IIa is predicted to have a significantly lower bandgap than the corresponding 1,6 isomer, IIb, (see FIG. 2) which does not have this option (Toussaint, et al., 1989). A second approach does not rely on resonance stabilization to incorporate quinoid character but builds it directly into the monomer and polymer (Toussaint, et al., 1989; Bredas, J. L., 1987; Kertesz, et al., 1987; Hanack, et al., 1991; Jenekhe, S. A., 1986, Wudl, et al., 1988; Zimmer, et al., 1984; Yamamoto, et al., 1981; Miyaura, et al., 1981; Kobmehl, G., 1983). These materials are based on polyarene-methylidenes, III. Neutral films of III (X, Y=S, m=2, n=1) shown in FIG. 3 display absorption maxima around 900 nm (Hanack, et al., 1991), reminiscent of other lowered E.sub.gap polymers like PITN.
Yet another approach to lowered E.sub.gap materials exploits the band crossings between highest occupied (HO) and next highest occupied (NHO) orbitals or lowest unoccupied (LU) and next lowest unoccupied (NLU) orbitals. (Tanaka, et al., 1987; Tanaka, et al., 1988) that occur in certain polymers like polyphenylene and polyperylene.
Theoretically, derivatives with lowered E.

REFERENCES:
patent: 3987060 (1976-10-01), Hashimoto
PCT/US/92/07604 Mar. 17, 1993 PCT Search Report.
Amer. et al., (1989), "Studies of Some Hindered 2,2'-Bithienyls and 3,3'-Bridged 2,2'-Bithienyls with Special Reference to Their UV Spectra and Oxidation Potentials," Phosphorus, Sulfur, and Silicon, 42:63-71, published in Europe.
Bakhshi et al., (1988), "On the Electronic Structure of Polythieno 3,4-C!Thiophene: A Polymer with Very Small Band Gap," Solid State Comm., 65:1203-1206.
Bolognesi et al., (1988), "Poly(dithieno 3,4-b:e',r'-d!thiophene): A New Transparent Conducting Polymer," J.C.S. Chem. Comm., 246-247.
Bredas, J. L., (1985), "Relationship between band gap and bond length alternation in organic conjugated polymers," J. Chem. Phys., 82:3808-3811.
Bredas, J. L., (1987), "Theoretical Design of Polymeric Conductors," Synthetic Metals, 17:115-121.
Bredas, et al., (1986), "Towards organic polymers with very small intrinsic band gaps. I. Electronic structure of polyisothianaphthene and derivatives," J. Chem. Phys., 85:4673-4678.
Bredas, et al., (1982), "Comparative theoretical study of the doping of conjugated polymers: Polarons in polyacetylene and polyparaphenylene," Phys. Rev., B26:5843-5854.
Bredas, et al., (1984), "The Role of Mobile Organic Radicals and Ions (Solution, Polarons and Bipolarons) in the Transport Properties of Doped Conjugated Polymers," Synthetic Metals,9:265-275.
Charles, G., (1963), "L'alcoylidenation par les imines des groupes methylenes actives. III. L'alcoylidenation du cyanacetamine et des nitroalcanes," Bull. Soc. Chim. Fr., 1573-1576.
Chung et al., (1984), "Charge storage in doped poly(thiophene): Optical and electrochemical studies," Phys. Rev. B, 30(2):702-710.
Colaneri et al., (1986), "Electrochemical and Opto-Electrochemical Properties of Poly(isothianaphthane)," Synthetic Metals, 14:45-52.
Ferraris et al., (1990), "Poly(N-isopropyl-2,5 di-(2-thienyl) pyrrole): a sterically hindered pyrrole-thiophene copolymer," New Polym. Mater., 2:41-65.
Ferraris et al., (1989), "Steric Effects on the Optical and Electrochemical Properties of N-Substituted Pyrrole-Thiophene Monomers and Polymers," J.C.S. Chem. Comm., 1318-1320.
Ferraris et al., (1991), "Approaches to narrow Bandgap Polymers," Polym. Mater Sci. Engn., 64:332-333.
Charles, G., (1960), "Sur la preparation de la fluorenone-imine," Bull. Soc. Chim. Fr., 421.
Grant et al., (1979), "Band Structure of Polyacetylene, (CH).sub.x," Solid State Commun., 29(3):225-229.
Hanack et al., (1991), "A new Class of Low Gap Polymers: Polyarenemethylidenes," Polym. Mater. Sci. Engn., 64-330-331.
Havinga, et al., (1989), "Water-Soluble Self-Doped 3-Substituted Polypyrroles," Chem. Mater., 1:650-659.
Ikenoue et al., (1991), "A novel substituted poly(isothianaphthene)," Synthetic Metals, 40:1-12.
Ikenoue, Y., (1990), "Synthesis and Characteristic Properties of Poly(Naphtho 2,3-c!thiophene) As A Series of Fused-Ring Conducting Polymers Analogous to Poly(isothisnaphthene)," Synthetic Metals, 35:263-270.
Jenekhe, S. A., (1986), "A class of narrow-band-gap semiconducting polymers," Nature, 322:345-347.
Jones et al., (1990), "Determination of the Electronic Structure of Thiophene Oligomers and Extrapolation to Polythiophene," J. Phys. Chem., 94:5761-5766.
Jordens et al., (1970), "Synthesis of Cyclopentadithiophenones," J. Chem., Soc., (C):273-277.
Jow et al., (1986), "Electrochemical Studies of Fused-Thiophene Systems," Synthetic Metals, 14:53-60.
Kaufman et al., (1983), "Charge Transport at Mid-Gap in Trans-(CH).sub.x : An Electrochemical Study," Solid State Comm., 47(8):585-589.
Kertesz et al., (1989), "Electronic Structure of Small Gap Polymers," Synthetic Metals, 28:C545-552.
Kertesz, et al., (1987), "Energy Gap and Bond Length Alternation in Heterosubstituted Narrow Gap Semiconducting Polymers," J. Chem. Phys., 91:2690-2692.
Kobayashi et al., (1985), "The electronic and electrochemical properties of poly(isothianaphthene)," J. Chem. Phys., 82(12):5717-5723.
Kossmehl, Gerhard, (1979), "Semicondu

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Low bandgap polymers from fused dithiophene diester does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Low bandgap polymers from fused dithiophene diester, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Low bandgap polymers from fused dithiophene diester will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2309168

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.