Cationic conjugated polymer as well as preparation method and application thereof

Abstract

The invention discloses a cationic conjugated polymer as well as a preparation method and application thereof. The structure of the cationic conjugated polymer is shown as a formula I, wherein Ar1 and D represent an N-containing heteroaryl group, an N-containing cycloalkenyl group or other conjugated groups; ar and Ar2 represent an aryl group, a heteroaryl group or other conjugated group; r6, R7 and R8 are the same or different and are independently selected from hydrogen, halogen, cyano, nitro, alkyl, alkenyl, alkynyl, alkoxy, polyethylene glycol, ether-containing substituent, halogen-substituted alkyl, aryl, heteroaryl, alkyl-substituted aryl or heteroaryl; y-represents an anion; n represents the polymerization degree. The cationic conjugated polymer has high electron migration rate, excellent solubility and film-forming property, can be applied to organic electrochemical transistors and organic thermoelectric devices, and realizes efficient energy conversion, excellent field effect mobility, excellent conductivity, good on / off current ratio and high stability.

Description

Technical Field

[0001] The invention relates to an organic conjugated polymer with a cationic compound as a structural unit and a preparation method thereof, as well as the application of the organic conjugated polymer as an organic semiconductor material in organic thermoelectric and organic electrochemical transistor devices, and belongs to the field of organic polymer functional materials. Background Art

[0002] The successful preparation of conductive polymer polyacetylene in the 1970s has attracted widespread attention from scientific researchers to organic conjugated polymers. In recent years, the research on organic conjugated polymers in the field of optoelectronic materials has made rapid progress, especially in optoelectronic fields such as organic light-emitting diodes, organic field-effect transistors, and organic solar cells, which have shown excellent device performance. Compared with traditional inorganic semiconductor materials, organic conjugated polymer semiconductor materials have incomparable advantages: the raw materials of organic conjugated polymers are cheap and easy to obtain, light in weight, flexible and bendable, and can be processed in solution, and the optical and electrical properties of the materials can be easily regulated by chemical modification (Bubnova, O.; Crispin, X. Energy Environ. Sci. 2012, 5, 9345-9362). These excellent properties have promoted the continuous deepening of the research on organic conjugated polymers, and they have also begun to emerge in important optoelectronic fields such as thermoelectric devices, organic electrochemical cells (OLECs) and organic electrochemical transistors (OECTs).

[0003] As a semiconductor device that can directly realize the mutual conversion of heat energy and electrical energy, thermoelectric devices can convert a large amount of waste heat and solar thermal energy in industrial production into electrical energy, thereby effectively solving the problem of energy shortage. Compared with traditional inorganic thermoelectric materials, organic thermoelectric materials have the advantages of low toxicity, light weight and large-area preparation, which has attracted extensive attention from scientific researchers in recent years and gradually achieved excellent device performance (Zhang, YH; Wang, YS; Gao, C.; Ni, ZJ; Zhang, XT; Hu, WP; Dong, HL Chem. Soc. Rev., 2023, 52, 1331). At present, organic thermoelectric materials generally improve the conductivity of materials by doping (n-doping / p-doping). However, the final state molecules obtained after doping are usually ionic compounds with positive and negative charges, and the stability of the material will be greatly reduced. At present, although the conductivity of organic thermoelectric materials after doping has been significantly improved compared with that before doping, there is still a large gap compared with traditional inorganic thermoelectric materials. Therefore, how to prepare high-conductivity organic conjugated materials with stable final state after doping is a key problem that needs to be solved urgently in the field of organic thermoelectrics.

[0004] Organic electrochemical transistors (OECTs) have become a powerful platform for developing organic bioelectronic applications. They can operate in aqueous solution, have a small operating voltage (usually less than 1V), and have a transconductance (the response sensitivity of source-drain current to gate voltage) that exceeds that of high-mobility materials such as graphene. They have good bio-device interfaces and biocompatibility. Therefore, organic electrochemical transistors have a wide range of applications in biochemical sensors, neural interface devices, and neuromorphic computing, and have attracted increasing attention. The performance of organic electrochemical transistors (OECTs) is usually used to evaluate the mixed ion-electron transport properties of conjugated polymers. In recent years, a variety of p-type polymers have been developed with μC* greater than 200F cm -1 V -1 s -1 (Kukhta, NA; Marks, A.; Luscombe, CK Chem. Rev. 2022, 122, 4325-4355) These polymers have fast response speeds and are suitable for high-speed sensing applications. However, n-type OECT materials lag far behind, with most n-type OECT materials having μC* values ​​less than 10F cm -1 V -1 s -1 , and the response time is slow (Ding, L.; Yu, ZD; Wang, XY; Yao, ZF; Lu, Y.; Yang, CY; Wang, JY; Pei, J. Chem. Rev. 2023, 123, 7421-7497). In addition, the performance and device stability of n-type OECT devices are poor, which greatly limits the application of OECT devices.

[0005] The design of conjugated molecules, especially the electron-donating or electron-accepting fragments, is of great importance in the preparation of high-performance conjugated polymers. Although there are many types of high-performance p-type (electron donor) polymers and bipolar polymers available, stable and processable n-type polymers with high electron affinity (about 4 eV) are not abundant. Therefore, how to design and synthesize efficient organic optoelectronic materials and further prepare high-performance electrochemical transistor devices has important social value and practical application significance.

[0006] Cationic conjugated polymers are a type of polymer that contains positive and negative ions. The final polymer obtained after doping is electrically neutral and has high stability. More importantly, cationic conjugated polymers have strong electron affinity and usually obtain very high conductivity after doping. Cationic conjugated polymers usually have good solubility in highly polar solvents such as water and trifluoroethanol. They are environmentally friendly and green in the processing of organic semiconductor devices. At the same time, they can avoid large steric substituents that hinder charge transfer between polymer chains, making the polymer present a dense stacking pattern in the solid state, significantly reducing the π-π stacking distance within and between chains, and can effectively improve the charge transfer ability between polymer chains.

[0007] US Patent Specification US8318894B2 describes a charged polymer and its application in photovoltaic cells, field effect transistors and light emitting diodes. Referring to their synthesis routes, a series of novel water-soluble and processable n-type conjugated polymers with bipyridine-phenyl conjugated donor-acceptor as structural units are reported (Izuhara, D.; Swager, TMJ Am. Chem. Soc. 2009, 131, 17724-17725. Izuhara, D.; Swager, TMJ Mater. Chem. 2011, 21, 3579-3584.).

[0008]

[0009] Subsequently, the homopolymer was tested in solution-processed organic thermoelectric generators (OTEGs) using it as an n-type semiconductor (Hwang, S.; Jr, PWJ; Yang, YS; Park, I.S.; Matsushima, T.; Adachi, C. Phys. Chem. Chem. Phys. 2016, 18, 29199-29207), showing a high electron mobility (σ = 33.3 S cm) at a doping concentration of 2.5 mM. -1 ) and a higher power factor (0.81μW m -1 K -2 ).

[0010] The present invention has found that although such polymers show good reversible electrochemical activity, electron affinity and conductivity, the synthesis method has certain defects and limitations. Due to the insolubility of the cationic polymer in the ring-closing process, the final ring-closing product is not completely ring-closed, which weakens the ability to transfer charge between polymer chains. In addition, since the ring-closing reaction needs to be carried out under strong acid conditions, the repeating structural units of the copolymer have great limitations and are highly destructive to unstable structural units. That is, the product a in the reaction formula cannot be completely reacted to generate the product a through the reaction conditions of the following formula.

[0011]

[0012] In addition, due to defects and limitations in the synthesis method, there are few types of polymers, and copolymers of this type of cationic conjugated donor-acceptor structural units have not yet been applied to thermoelectric materials and organic electrochemical transistor devices. Therefore, how to design and synthesize efficient cationic conjugated polymers and explore their applications in thermoelectric materials and organic electrochemical transistor devices has great scientific value and significance. Summary of the invention

[0013] In response to a series of prominent problems currently faced by organic thermoelectric and electrochemical transistor devices, such as low conductivity and poor stability, the present invention uses two new synthesis methods to design a series of cationic conjugated polymers with different conjugated structures, and systematically studies their molecular structures and corresponding device performance parameters.

[0014] The first method of the present invention is optimized based on the method mentioned in patent US8318894B2, that is, the dilute solution of halogenated is under nitrogen protection reflux conditions, and the dilute solution of cyclization reagent is added dropwise to obtain cationic conjugated polymer. The solubility of conjugated polymer is increased by heating and reducing the concentration method, which is conducive to the complete ring closure of polymer. Based on the above research findings, the polymer synthesized by the above method is relatively limited, such as polymers based on DPP (pyrrolopyrrole diketo) and IID (isoindigo) structural units, due to the instability of its structure, the polymer cannot be reacted by the ring closure mode of acid solution (such as thionyl chloride). Therefore, the second method of the present invention is to first close the ring of small molecule compounds by acid solution (such as thionyl chloride), and realize complete ring closure, and then in polar solvents (DMSO, NMP, etc.) with different structural units (such as DPP, IID, etc.) by Stille, Suzuki and other coupling reactions to obtain a series of novel cationic conjugated polymers, and further prepare excellent organic thermoelectric and electrochemical transistor devices.

[0015] In thermoelectric devices, the conductivity of cationic polymers can reach up to 480 S cm -1, the average maximum conductivity is 412S cm -1 After 1 min of doping, the power factor reaches a maximum value of 58 μW m -1 K -2 , which has important practical significance for the research and application of thermoelectric devices. This series of cationic polymers has a high electron mobility. In the field of organic electrochemical transistor devices, the electron mobility of cationic conjugated polymers can reach 0.25cm 2 V -1 s -1 , volume capacitance can reach 485F cm -3 , μC* can reach 120F cm -1 V -1 s -1 , providing a new idea and development direction for the development of new, high-performance, and environmentally friendly electrochemical transistor devices. In addition, by culturing human immortalized epidermal cells in a culture dish modified with a polymer film, the experimental results showed no cell death, proving that the cationic polymer film has good biocompatibility and has achieved the amplification of human eye and human electrocardiogram signals.

[0016] In a first aspect of the present invention, a conjugated polymer of a cationic repeating unit containing a nitrogen heterocycle is provided.

[0017]

[0018] Among them, Ar 1 and D represent a nitrogen-containing heteroaryl, cycloalkenyl or other conjugated group; Ar and Ar 2 represents an aryl group, a heteroaryl group or other conjugated group; R 6 , R 7 and R 8 are the same or different, independently selected from hydrogen, halogen (F, Cl, Br, I), cyano, nitro, alkyl, alkenyl, alkynyl, alkoxy, polyethylene glycol, ether-containing substituents, halogen-substituted alkyl, halogen-substituted alkoxy, aryl, heteroaryl, alkyl-substituted aryl or heteroaryl, and may form a ring by itself, and / or may form a bond with another repeating unit or a terminal group of the polymer; - represents anion; n is an integer representing the degree of polymerization of the polymer.

[0019] The above-mentioned alkyl group is preferably a C1-C46 straight chain or branched chain alkyl group, more preferably a C1-C36 straight chain or branched chain alkyl group, and most preferably a C1-C4 alkyl group.

[0020] The above-mentioned halogen-substituted alkyl group is preferably a C1-C46 straight-chain or branched halogen-substituted alkyl group, more preferably a C1-C36 straight-chain or branched halogen-substituted alkyl group, and most preferably a C1-C4 straight-chain alkyl group substituted with fluorine, chlorine and / or bromine.

[0021] The above-mentioned alkoxy group is preferably a C1-C46 straight-chain or branched alkoxy group, and more preferably a C1-C36 straight-chain or branched alkoxy group.

[0022] The above-mentioned halogen-substituted alkoxy group is preferably a C1-C46 straight-chain or branched halogen-substituted alkoxy group, more preferably a C1-C36 straight-chain or branched halogen-substituted alkoxy group, and most preferably a C1-C4 halogen-substituted alkoxy group.

[0023] The alkyl-substituted aryl group is preferably a phenyl group having one to three C1-C4 alkyl substituents.

[0024] The polyethylene glycol group is preferably a C2-C36 linear or branched polyethylene glycol group, and more preferably a C2-C18 linear or branched polyethylene glycol group.

[0025] The above-mentioned ether-containing substituent is preferably a C1-C3 ether bond-containing group, such as -CH2-O-CH3, -CH2-O-C2H5.

[0026] The above alkenyl group is preferably a C2-C18 alkenyl group, more preferably a C2-C10 alkenyl group, and most preferably a C2-C6 alkenyl group.

[0027] The above-mentioned alkynyl group is preferably a C2-C18 alkynyl group, more preferably a C2-C10 alkynyl group, and most preferably a C2-C6 alkynyl group.

[0028] The above-mentioned aryl group is preferably a C6-C30 aryl group, such as phenyl, biphenyl, naphthyl, anthracenyl and the like.

[0029] The above-mentioned heteroaryl group is preferably a C2-C26 heteroaryl group, such as pyridyl, thienyl, pyrazinyl, piperazinyl and the like.

[0030] The above-mentioned N-containing cycloalkenyl group is exemplified by 1,3-diazacyclopentadiene and 1,2-dihydropyridine.

[0031] Preferably, Ar, Ar 1 and Ar 2 It is a C6-C30 aryl group, a C2-C26 heteroaryl group, or other conjugated groups of C2-C26, such as -C=C-, -C=CC=C-.

[0032] Y -The anion is preferably selected from halides (e.g., chloride, bromide, iodide, fluoride), nitrates, sulfates, phosphates, carboxylates and acetates, i.e., selected from I - , Cl - Br - 、F - 、NO3 - 、SO4 2- PO4 3- 、COO - 、CH3COO - wait.

[0033] Based on the above research, the present invention proposes two new methods for synthesizing the polymer shown in formula I. The first synthesis method is a method for synthesizing the polymer shown in general formula d from a raw material (such as a 2,5-dibromo-p-xylene derivative), and then using a halogenated organic solvent as a cyclization reaction solvent, under nitrogen protection reflux conditions, a dilute solution of a cyclization reagent is added dropwise to a dilute solution of the polymer of formula d to obtain a quaternary nitrogen cationic polymer shown in general formula I.

[0034]

[0035] Among them, its derivative (compound of formula C) is obtained from 2,5-dibromo-p-xylene through free radical reaction (bromination with bromosuccinimide (NBS)), Wittig reaction (benzyl bromide reacts with triphenylphosphine to form ylides, which then react with aldehydes to form styrene derivatives), oxidative addition reaction (olefins are reacted with hydrogen peroxide to obtain phenylethanol derivatives), electrophilic substitution reaction (tert-butyldimethylchlorosilane (TBDMSCl) protects the hydroxyl group) and Suzuki coupling reaction (reaction with bispinacol ester).

[0036] Reaction conditions (1) are: monomers shown in c and aromatic, heteroaromatic or other conjugated monomers R*-Ar 2 (R 8 )-R* polymerizes to form the polymer shown in d, where R 11 represents an alkoxy group or a silyloxy group, and the functional group may be tert-butyldimethylsilyloxy, trimethylsilylalkoxy, dimethylisopropylsilylalkoxy, etc.; R 9 and R* represent the functional groups required for the monomer polymerization reaction. For example, for Suzuki coupling reaction, the functional group can be halogen, boric acid or boron ester. 9 It can be a boronic acid group, a boronic ester or a halogen (note that when R* is a halogen, R 9 is a borate ester or a boronic acid group; when R* is a borate ester or a boronic acid group, R 9for a Stille coupling reaction, the functional group may be a halogen or an alkyltin; for a Sonogashira coupling reaction, the functional group may be a halogen or an ethynyl; for a Heck coupling reaction, the functional group may be a halogen or a vinyl; for a Kumada coupling reaction, the functional group may be a halogen; for a carbon-hydrogen bond activation coupling reaction, the functional group may be a halogen or hydrogen; for a Hiyama coupling reaction, the functional group may be a halogen or a silane. 2 represents an optionally substituted C6-C30 aryl group or a C2-C26 heteroaryl group or other conjugated groups of C2-C26. 2 (R 8 )-R* can be selected from the following compounds represented by formula II-1 to II-20:

[0037]

[0038] R 12 It represents a hydrogen atom, a halogen atom (such as F, Cl, etc.), a nitro group, an amino group, a cyano group, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, a halogen-substituted alkyl group, a halogen-substituted alkoxy group, and the like.

[0039] b and b' can be independently selected from the following structures: -S-, -Se-, -O- and -NR 8 —;

[0040] c and c' can be independently selected from the following structures: -N=, =N-, -SiR 8 =, =SiR 8 —, —CR 8 = and = CR 8 —;

[0041] d and d' can be independently selected from the following structures: -N=, =N-, -SiR 8 =, =SiR 8 —, —CR 8 =, =CR 8 —, =CR 8 R 8 —CR 8 R 8 —, —CR 8 —CR 8 =;

[0042] e can be selected from the following structures: -S-, -S(O)-, -S(O)2-, -O-, -SiR 8 R 8 —, —CR 8 R 8 —CR 8 R8 —, —CR 8 =CR 8 —, —C(O)— and —C(C(CN)2)—;

[0043] g, h, g', h' can be independently selected from the following structures: -CR 8 =, =CR 8 —, and —N= and =N—;

[0044] R 14 and R 15 are the same or different and are selected from hydrogen, fluorine, cyano, alkyl, halogen-substituted alkyl, phenyl and alkyl-substituted phenyl;

[0045] The above R 8 Examples of the group include hydrogen, halogen (F, Cl, Br, I), cyano, nitro, alkyl, alkenyl, alkynyl, alkoxy, polyethylene glycol, ether-containing substituents, halogen-substituted alkyl, aryl, heteroaryl, alkyl-substituted aryl or heteroaryl, and the like.

[0046] The above-mentioned alkyl group is preferably a C1-C46 straight chain or branched chain alkyl group, and more preferably a C1-C36 straight chain or branched chain alkyl group.

[0047] The polyethylene glycol group is preferably a C2-C36 linear or branched polyethylene glycol group, and more preferably a C2-C18 linear or branched polyethylene glycol group.

[0048] The above-mentioned halogen-substituted alkyl group is preferably a C1-C46 straight-chain or branched halogen-substituted alkyl group, and more preferably a C1-C36 straight-chain or branched halogen-substituted alkyl group.

[0049] The above-mentioned alkoxy group is preferably a C1-C46 straight-chain or branched alkoxy group, and more preferably a C1-C36 straight-chain or branched alkoxy group.

[0050] The above-mentioned halogen-substituted alkoxy group is preferably a C1-C46 straight-chain or branched halogen-substituted alkoxy group, and more preferably a C1-C36 straight-chain or branched halogen-substituted alkoxy group.

[0051] The above alkenyl group is preferably a C2-C18 alkenyl group, more preferably a C2-C10 alkenyl group, and most preferably a C2-C6 alkenyl group.

[0052] The above-mentioned alkynyl group is preferably a C2-C18 alkynyl group, more preferably a C2-C10 alkynyl group, and most preferably a C2-C6 alkynyl group.

[0053] Wherein, the monomer R*-Ar 2 (R 8 )-R* is more preferably one of the following structures:

[0054]

[0055] Reaction condition (2) is to close the repeating unit containing a nitrogen heterocycle so that R 11 The group leaves to obtain a cationic ring system of quaternary nitrogen to generate a cationic conjugated polymer of formula I, wherein Y - It is a halogen anion. The technical key point of this step is to use a halogenated organic solvent as a cyclization reaction solvent, control the concentration of the reaction substrate (polymer of formula d) in the range of 3 to 5 mM under anhydrous and oxygen-free conditions, and the reaction temperature is 75 to 100°C, preferably 80 to 85°C, and add a cyclization reagent (dissolved in a cyclization reaction solvent) with a concentration of 2 to 2.5 M to the solution of the polymer of formula d. The cyclization reagent is preferably phosphoryl chloride, sulfonyl chloride, phosgene and sulfuryl chloride, and sulfonyl chloride (dimethyl sulfoxide) is most preferred. The cyclization reaction solvent is preferably dichloromethane, chlorobenzene, 1,1,2,2,-tetrachloroethane, chloroform, and more preferably chloroform. The reaction time is preferably 16-36 hours, more preferably 20-24 hours.

[0056] In the first synthesis method, the nitrogen-containing heterocyclic moiety in Formula I It can be one of the following structures:

[0057]

[0058] The following are some typical examples of polymer molecules of formula I that can be prepared by the first synthesis method described above:

[0059]

[0060] The present invention proposes a second new method for synthesizing the polymer shown in formula I. Compared with the first synthesis method, the second method has a wider applicability. For example, the structural units based on DPP (dione pyrrolopyrrole) and IID (isoindigo) that are unstable under acid conditions and cannot be obtained by the first method can be obtained by the second method. In the second synthesis method, the monomer shown in the general formula g and the monomer R*-Ar 2 (R 8 )-R* is polymerized to form a polymer shown in Formula I, and, due to the water solubility of the cationic monomer unit, we use a polar organic solvent (dimethyl sulfoxide, N-methylpyrrolidone, etc.) as the reaction solvent. 9 It represents the functional group required for the polymerization reaction of the polymerizable monomer, such as halogen, boric acid or boron ester, alkyl tin, acetylene, vinyl, hydrogen and silane.

[0061]

[0062] The present invention provides a method for synthesizing a cationic repeating unit shown in general formula G from a raw material (such as a 2,5-dibromo-p-xylene derivative), and then polymerizing the repeating unit shown in general formula G and an aromatic or conjugated structure monomer under the conditions of an anhydrous and oxygen-free polar organic solvent (such as dimethyl sulfoxide, N-methylpyrrolidone) to form a quaternary nitrogen cationic polymer shown in formula I.

[0063]

[0064] Reaction condition (3) is to perform ring closure on the compound of formula c so that R 11 The group leaves to obtain a quaternary nitrogen cationic ring system, generating the compound shown in formula g. 11 Represents an alkoxy group or a silyloxy group, and the functional group may be tert-butyldimethylsilyloxy, trimethylsilylalkoxy, dimethylisopropylsilylalkoxy, etc. The cyclization reagent is phosphorus oxychloride, sulfonyl chloride, phosgene, and sulfuryl chloride, etc., preferably sulfonyl chloride (dimethyl sulfoxide). The reaction temperature is 25 to 150°C, preferably 55 to 100°C, and more preferably 80 to 85°C. The reaction solvent is preferably dichloromethane, tetrahydrofuran, acetonitrile, chlorobenzene, 1,1,2,2,-tetrachloroethane, chloroform, and more preferably chloroform. The reaction time is preferably 12 to 36 hours, and more preferably 18 to 24 hours.

[0065] Reaction conditions (4) are the repeating unit monomer and monomer R*-Ar shown in formula g 2 (R 8 )-R* polymerizes to form the polymer shown in I, wherein R 9 and R* represents the functional group required for the monomer to undergo polymerization reaction, for example, for Suzuki coupling reaction, the functional group may be halogen, boric acid group or boron ester group; for Stille coupling reaction, the functional group may be halogen or alkyltin; for Sonogashira coupling reaction, the functional group may be halogen or ethynyl group; for Heck coupling reaction, the functional group may be halogen or vinyl group; for Kumada coupling reaction, the functional group may be halogen; for carbon-hydrogen bond activation coupling reaction, the functional group may be halogen or hydrogen; for Hiyama coupling reaction, the functional group may be halogen or silane group. The reaction temperature is 25-200°C, preferably 80-150°C, more preferably 110°C. The reaction solvent is preferably o-xylene, o-dichlorobenzene, N,N-dimethylformamide, chlorobenzene, N-methylpyrrolidone, dimethyl sulfoxide, more preferably dimethyl sulfoxide. The reaction time is preferably 12-72 hours, more preferably 36-48 hours. Ar 2 represents an optionally substituted C6-C30 aryl group or a C2-C26 heteroaryl group or other conjugated groups of C2-C26. 2 (R 8)-R* In addition to the compounds shown above, the compounds shown in the following formulas IV-1 to IV-6 can also be selected:

[0066]

[0067] a and a' can be independently selected from the following structures: -S-, -Se-, -O- and -NR 8 —;

[0068] m and m' can be independently selected from the following structures: -S-, -S(O)-, -S(O)2-, -O-, -NR 8 —,—SiR 8 R 8 —, —CR 8 R 8 —CR 8 R 8 —, —CR 8 =CR 8 —, —C(O)— and —C(C(CN)2)—;

[0069] n and n' can be independently selected from the following structures: -N=, =N-, -SiR 8 =, =SiR 8 —,—SiR 8 R 8 —, —CR 8 R 8 —CR 8 R 8 —and—CR 8 =CR 8 —;

[0070] The above R 8 It can be hydrogen, halogen (F, Cl, Br, I), cyano, nitro, alkyl, alkenyl, alkynyl, alkoxy, polyethylene glycol, ether-containing substituents, halogen-substituted alkyl, aryl, heteroaryl, alkyl-substituted aryl or heteroaryl, etc.;

[0071] The above-mentioned alkyl group is preferably a C1-C46 straight chain or branched chain alkyl group, and more preferably a C1-C36 straight chain or branched chain alkyl group.

[0072] The polyethylene glycol group is preferably a C2-C36 linear or branched polyethylene glycol group, and more preferably a C2-C18 linear or branched polyethylene glycol group.

[0073] The above-mentioned halogen-substituted alkyl group is preferably a C1-C46 straight-chain or branched halogen-substituted alkyl group, and more preferably a C1-C36 straight-chain or branched halogen-substituted alkyl group.

[0074] The above-mentioned alkoxy group is preferably a C1-C46 straight-chain or branched alkoxy group, and more preferably a C1-C36 straight-chain or branched alkoxy group.

[0075] The above-mentioned halogen-substituted alkoxy group is preferably a C1-C46 straight-chain or branched halogen-substituted alkoxy group, and more preferably a C1-C36 straight-chain or branched halogen-substituted alkoxy group.

[0076] The above alkenyl group is preferably a C2-C18 alkenyl group, more preferably a C2-C10 alkenyl group, and most preferably a C2-C6 alkenyl group.

[0077] The above-mentioned alkynyl group is preferably a C2-C18 alkynyl group, more preferably a C2-C10 alkynyl group, and most preferably a C2-C6 alkynyl group.

[0078] Wherein, the aromatic or conjugated structure monomer R*-Ar 2 (R 8 )-R* is more preferably one of the following structures:

[0079]

[0080] The following are some typical examples of polymer molecules of formula I prepared by the second synthesis method described above:

[0081]

[0082] In the second aspect of the present invention, the cationic conjugated polymer shown in the above formula I is used as an organic semiconductor material in an organic thermoelectric device. Thermoelectric conversion technology is a technology that directly converts heat energy and electrical energy using the Seebeck effect and Peltier effect of semiconductor materials. Thermoelectric conversion devices do not require the use of moving parts or toxic working fluids, and play a very important role in solving increasingly severe global energy and environmental problems. They are developed and utilized in the fields of industrial waste heat utilization, solar thermal composite power generation, etc.

[0083] Thermoelectric conversion devices generally consist of three parts: heat source, heat sink and thermopile. Thermoelectric piles are composed of a series of thermoelectric pairs that can convert thermal energy into electrical energy. Thermoelectric pairs are generally composed of different types of N / P type thermoelectric materials. When a temperature gradient appears at its two ends, namely the heat source end and the heat sink end, a potential difference can be generated at its two ends. Using this principle of temperature difference power generation, the thermoelectric power generation device can generate electricity with the help of the temperature difference between human body temperature and external temperature to provide power for wearable devices.

[0084] The manufacturing process of the thermoelectric device containing the polymer of the present invention can refer to the processing techniques in CN108470818A, CN109524535A and CN108305935A.

[0085] The present invention provides a method for synthesizing a polymer of formula I and the use of such polymer in an organic electrochemical transistor device and a thermoelectric material device. The two synthesis methods can obtain water-soluble cationic conjugated polymers that cannot be obtained by existing synthesis methods in high yield. The polymer of the present invention has excellent solubility and excellent film-forming properties in polar solvents. When the polymer according to the present invention is used in an organic electrochemical transistor and an organic thermoelectric device, efficient energy conversion, excellent field effect mobility and / or excellent conductivity, good on / off current ratio and / or excellent stability can be observed.

[0086] In a third aspect of the present invention, the cationic conjugated polymers shown in the above formula I are used as organic semiconductor materials in optoelectronic devices such as organic electrochemical transistors (OECTs). Therefore, the present invention provides OECT devices comprising the polymers of the present invention. For the present invention, organic electrochemical transistor devices utilize electrochemical redox reactions of organic materials. These devices contain electrolytes and conductive polymers that can switch between oxidized and reduced states. One of these oxidation states corresponds to a low conductivity of the material, preferably zero, while the other oxidation state corresponds to a higher conductivity than the first state. The manufacture of the OECT device can refer to CN1494743A.

[0087] The OECT device includes: a source contact; a drain contact; at least one gate; an electrochemically active element arranged between and in direct electrical contact with the source and drain contacts, the electrochemically active element comprising a transistor channel and being composed of a material comprising an organic material, the organic material being capable of electrochemically changing its conductivity by changing its redox state; a solidified electrolyte, the solidified electrolyte being in direct electrical contact with the electrochemically active element and the at least one gate and being placed therebetween in a manner that blocks the flow of electrons between the electrochemically active element and the gate, whereby the flow of electrons between the source contact and the drain contact can be controlled by a voltage applied to the gate.

[0088] The structure of the electrochemical transistor device according to the present invention is beneficial because it enables the realization of a layered transistor device with only a few layers, for example having a patterned layer of material comprising an organic material, the layer comprising source, drain contacts and a gate, and an electrochemically active element. The source and drain contacts are then preferably formed with a continuous sheet of P2 material forming a conductive material to which direct electrical contact is made. The gate may also be formed with another conductive material. In order to provide the necessary electrochemical reaction and thereby change the conductivity of the active element, a solidified electrolyte is arranged so that it is in direct electrical contact with both the active element and the gate.

[0089] The electrochemical transistor device can be prepared by depositing the different components comprising the polymer of the present invention on a support by conventional printing methods such as screen printing, offset printing, inkjet printing and offset printing as described in Modern Coating and Drying Technology (1992), eds ED Cohen and E.B. gutoff, VCH Publisher Inc, New York, NY, USA, or coating methods such as blade coating, cast coating, extrusion coating and flow coating. BRIEF DESCRIPTION OF THE DRAWINGS

[0090] Figure 1 It is the structural formula of the cationic conjugated polymer shown in Formula I of the present invention.

[0091] Figure 2 This is a graph showing the change in conductivity of polymer P2 as active layer material versus doping time.

[0092] Figure 3 This is a graph showing the change of Seebeck coefficient of polymer P2 as active layer material with doping time.

[0093] Figure 4 This is a graph showing the power factor of polymer P2 as the active layer material changing with doping time.

[0094] Figure 5 This is a graph showing the change in conductivity of polymer P4 as an active layer material versus doping time.

[0095] Figure 6 This is a graph showing the change of Seebeck coefficient of polymer P4 as active layer material with doping time.

[0096] Figure 7 This is a graph showing the power factor of polymer P4 as the active layer material changing with doping time.

[0097] Figure 8 The schematic diagram of the device structure of an organic electrochemical transistor made by using the polymer of the present invention as an active layer material.

[0098] Fig. 9 The active material is polymer P2 Figure 2 The transfer characteristic curve of the device shown in the figure (where V DS is the source-drain voltage, I DS is the source-drain current, V GS is the gate voltage).

[0099] Fig.10 The active material is polymer P2 Figure 2 The output characteristic curve of the device shown in the figure (where V DS is the source-drain voltage, I DSis the source-drain current, V GS is the gate voltage).

[0100] Fig.11 The active material is polymer P2 Figure 2 The switching test curve of the device shown in the figure (where V DS is the source-drain voltage, I DS is the source-drain current, V GS is the gate voltage, and τ is the response time).

[0101] Fig.12 The active material is polymer P2 Figure 2 Inverter voltage transfer characteristics and gain curves for the device shown. DETAILED DESCRIPTION

[0102] The present invention will be further described in detail below through embodiments in conjunction with the accompanying drawings, but the scope of the present invention is not limited in any way.

[0103] Example 1

[0104]

[0105] Synthesis route of compound 1: 2,5-dibromo-p-xylene (20 g, 76.4 mmol), bromosuccinimide (NBS) (30 g, 168.1 mmol) and azobisisobutyronitrile (AIBN) (2.6 g, 15.3 mmol) were added to a 1000 mL two-necked bottle, the reaction system was treated with anhydrous oxygen, carbon tetrachloride (500 mL) was added under nitrogen protection, and the reaction was refluxed for 36 h. Cool to room temperature, spin dry, remove the solvent in the reaction system, extract with chloroform and water three times, combine the organic phases, dry with anhydrous sodium sulfate, concentrate, and recrystallize with ethanol to obtain pale yellowish white crystals 1, about 26.7 g, with a yield of 83.6%. 1 HNMR (400MHz, Chloroform-d) δ7.66 (s, 1H), 4.51 (s, 2H).

[0106] Example 2

[0107]

[0108] Synthesis route of compound 2: Add compound 1 (2.5 g, 6.0 mmol) and triphenylphosphine (3.9 g, 15.0 mmol) to a 100 mL two-necked bottle, treat the reaction system to be anhydrous and oxygen-free, add N,N-dimethylformamide (DMF) (30 mL) under nitrogen protection, and react under reflux for 24 h. Cool to room temperature, stop the reaction, a large amount of white solid precipitates, filter to obtain a white solid, and dry. Transfer the white solid (4.0 g, 6.0 mmol) to a 100 mL two-necked bottle, add paraformaldehyde (3.6 g, 120.0 mmol), treat the reaction system to be anhydrous and oxygen-free, add THF (30 mL) under nitrogen protection, then slowly add a solution of potassium tert-butoxide (2.0 g, 18.0 mmol) in THF (10 mL), heat to about 65 ° C and react for 12 h. The mixture was cooled to room temperature, extracted with dichloromethane and water for three times, the organic phases were combined, dried over anhydrous sodium sulfate, concentrated, and separated by column chromatography using petroleum ether as eluent to obtain a white solid powder 2, about 1.56 g, with a yield of 92.6%. 1 H NMR (400MHz, Chloroform-d) δ7.72 (s, 1H), 6.95 (dd, J = 17.4, 11.0Hz, 1H), 5.71 (d, J = 17.4Hz, 1H), 5.40 (d, J = 11.1Hz, 1H).

[0109] Example 3

[0110]

[0111] Synthesis route of compound 3: Add compound 2 (2.5 g, 8.7 mmol) to a 250 mL two-necked bottle, treat the system to be anhydrous and oxygen-free, add THF (40 mL) under nitrogen protection, ice-water bath to about 0 ° C, slowly drop 9-BBN (0.5 M in THF, 45 mL, 22.5 mmol) into the reaction system, add dropwise, return to room temperature, and continue to react for 12 h. Ice-water bath the reaction system to about 0 ° C, slowly drop methanol (15 mL) into the reaction system to quench. Subsequently, inject an aqueous solution of sodium hydroxide (2 M, 75 mL) into the reaction system, continue to slowly add hydrogen peroxide (15 mL) to the reaction system in batches, and continue to react for 2 h under ice-water bath conditions. Return to room temperature, extract three times with ether and water, combine the organic phases, dry over anhydrous sodium sulfate, concentrate, and use petroleum ether: ethyl acetate = 15:1 as an eluent for column chromatography separation to obtain a white solid 3, about 2.1 g, with a yield of 74.2%. 1H NMR (400MHz, Dimethyl sulfoxide-d6) δ7.55 (s, 1H), 4.76 (s, 1H), 3.59 (t, J = 6.8 Hz, 2H), 2.80 (t, J = 6.8 Hz, 2H).

[0112] Example 4

[0113]

[0114] Compound 4 Synthesis route: Add compound 3 (2.5 g, 7.8 mmol) and imidazole (2.1 g, 31.1 mmol) to a 100 mL two-necked bottle, treat the system with anhydrous oxygen, add DMF (10 mL) under nitrogen protection, ice-water bath to about 0 ° C, add TBDMSCl (2.8 g, 18.7 mmol) DMF (5 mL) solution to the reaction system, and continue to stir the reaction for 30 min. Then, return to room temperature and continue stirring for 24 h. After the reaction is completed, extract with saturated sodium chloride aqueous solution and ethyl acetate three times, combine the organic phases, dry over anhydrous sodium sulfate, concentrate, and use petroleum ether: ethyl acetate = 20:1 as eluent for column chromatography separation to obtain a white solid 4, about 3.57 g, with a yield of 83.5%. 1 H NMR (400MHz, Chloroform-d) δ7.44 (s, 1H), 3.79 (t, J = 6.7Hz, 2H), 2.90 (t, J = 6.7Hz, 2H), 0.87 (s, 9H), -0.02 (s, 6H).

[0115] Example 5

[0116]

[0117] Synthesis route of compound 5: Compound 4 (0.3 g, 0.5 mmol), Pd(dppf)Cl2 (23.7 mg, 0.03 mmol), bipinacol borate (BPin)2) (0.5 g, 2.0 mmol) and anhydrous potassium acetate (0.4 g, 4.0 mmol) were added to a 50 mL Schlenk tube, 1,4-dioxane (10 mL) was redistilled as a solvent, and the system was subjected to anhydrous and oxygen-free treatment, and the temperature was raised to about 100°C for reaction for 36 h. Cool to room temperature, spin dry the solvent, extract with dichloromethane and water three times, combine the organic phases, dry over anhydrous sodium sulfate, concentrate, and use petroleum ether: ethyl acetate = 15:1 as an eluent for column chromatography separation to obtain a white solid 5, about 0.25 g, with a yield of 72.3%. 1H NMR (400MHz, Chloroform-d) δ7.64 (s, 1H), 3.75 (t, J = 7.4Hz, 2H), 3.09 (t, J = 7.4Hz, 2H), 1.34 (s, 12H), 0.88 (s, 9H), -0.01 (s, 6H).

[0118] Example 6

[0119]

[0120] Compound 6 Synthesis route: Add compound 5 (0.3 g, 0.5 mmol), Pd(PPh3)4 (53.6 mg, 0.05 mmol), 5-bromo-2-iodopyridine (0.6 g, 2.0 mmol) and anhydrous cesium carbonate (1.0 g, 3.0 mmol) into a 50 mL Schlenk tube, ethylene glycol dimethyl ether (DME, 10 mL) and H2O (5 mL) as a mixed solution as solvent, freeze-dry three times, and treat the system with oxygen. Heat to about 100 ° C and react for 48 h. Cool to room temperature, concentrate the reaction solution, extract three times with dichloromethane and water, combine the organic phases, dry over anhydrous sodium sulfate, concentrate, and use petroleum ether: ethyl acetate = 25:1 as an eluent for column chromatography separation to obtain a white solid powder 6, i.e., PyPh2Br, about 0.17 g, with a yield of 51.6%. 1 H NMR (400MHz, Chloroform-d) δ8.75 (d, J=2.2Hz, 1H), 7.88 (dd, J=8.3, 2.4Hz, 1H), 7.37 (d, J=8. 3Hz, 1H), 7.32 (s, 1H), 3.71 (t, J = 7.3Hz, 2H), 2.94 (t, J = 7.3Hz, 2H), 0.80 (s, 9H), -0.08 (s, 6H).

[0121] Example 7

[0122]

[0123] Polymer P1 synthesis route: Add compound 6 (100 mg, 141.5 μmol), trans-1,2-bis(tributyltin)ethylene (85.77 mg, 141.5 μmol), Pd2(dba)3 (5.18 mg, 5.7 μmol) and P(o-tol)3 (6.89 mg, 22.6 μmol) to a 25 mL Schlenk tube, use redistilled toluene (6 mL) as solvent, freeze-dry for three times, and treat the system to be anhydrous and oxygen-free. Heat to about 110 ° C and react for 48 hours. Cool to room temperature, pour the reaction solution into methanol solution (200 mL), let it settle for 10 minutes, filter, and wash the filter cake with methanol several times. The obtained polymer was wrapped with filter paper, put into a Soxhlet extraction apparatus, and extracted with methanol, acetone, n-hexane, dichloromethane and chloroform respectively. The chloroform component was collected to obtain an off-white solid P1, about 29.1 mg, with a yield of 35.8%. 1 H NMR (400MHz, Chloroform-d) δ8.87(s,1H),7.99(s,1H),7.53(s,1H),7.42(s,1H),7.29(s,1H),3.78(s,2H),3.05(s,2H),0.83(s,9H),-0.05(s,6H).

[0124] Example 8

[0125]

[0126] Synthesis route of polymer P2: Add the polymer P1 (50 mg, 87.0 μmol) obtained by extracting the chloroform component into a 100 mL two-necked bottle, treat the system to be anhydrous and oxygen-free, add chloroform (HPLC, 50 mL) under nitrogen protection, heat to about 80 ° C, react for 10 min, slowly add thionyl chloride (1 mL) chloroform (5 mL) solution to the reaction system, add dropwise, continue to react for 24 h. Cool to room temperature, spin dry the solvent, remove excess thionyl chloride, add chloroform to the reaction system, filter, and wash the filter cake repeatedly with chloroform to obtain a brown solid P2, about 30.83 mg, with a yield of 92.5%. 1 HNMR (400MHz, D2O) δ9.14 (s, 1H), 8.87 (s, 1H), 8.64 (s, 1H), 8.27 (s, 1H), 7.70 (s, 1H), 4.94 (s, 2H), 3.51 (s, 2H), number average molecular weight M n =23.4Kda.

[0127] Example 9

[0128]

[0129] Synthesis route of polymer P3: Add compound 6 (100 mg, 141.5 μmol), (3,4-difluorothiophene-2,5-diyl)bis(trimethyltin) (63.07 mg, 141.5 μmol), Pd2(dba)3 (5.18 mg, 5.7 μmol) and P(o-tol)3 (6.89 mg, 22.6 μmol) to a 25 mL Schlenk tube, use redistilled toluene (6 mL) as solvent, freeze-dry for three times, and treat the system to be anhydrous and oxygen-free. Heat to about 110 ° C and react for 48 hours. Cool to room temperature, pour the reaction solution into methanol solution (200 mL), let it settle for 10 minutes, filter it, and wash the filter cake with methanol several times. The obtained polymer was wrapped with filter paper, put into a Soxhlet extraction apparatus, and extracted with methanol, acetone, n-hexane, dichloromethane and chloroform respectively. The chloroform component was collected to obtain a yellow solid P3, about 42.99 mg, with a yield of 45.6%. 1 H NMR(400MHz,Chloroform-d)δ9.03(s,1H),8.07(d,J=7.4Hz,1H),7.61(d,J=7 .3Hz,1H),7.44(s,1H),3.80(s,2H),3.06(s,2H),0.83(s,9H),-0.04(s,6H).

[0130] Example 10

[0131]

[0132] Synthesis route of polymer P4: Add the polymer P2 (50 mg, 75.0 μmol) obtained by extracting the chloroform component into a 100 mL two-necked bottle, treat the system to be anhydrous and oxygen-free, add chloroform (HPLC, 50 mL) under nitrogen protection, heat to about 80 ° C, react for 10 min, slowly add thionyl chloride (1 mL) chloroform (5 mL) solution to the reaction system, add dropwise, continue to react for 24 h. Cool to room temperature, spin dry the solvent, remove excess thionyl chloride, add chloroform to the reaction system, filter, and wash the filter cake repeatedly with chloroform to obtain a brown-red solid P4, about 32.44 mg, with a yield of 91.2%. 1 HNMR(400MHz,D2O+MeOD)δ9.40(s,1H),8.98(s,1H),8.83(s,1H),8.42(s,1H),5.06(s,2H),3.60(s,2H).

[0133] Embodiment 11

[0134]

[0135] Synthesis route of polymer P5: Add compound 6 (100 mg, 141.5 μmol), 5,5'-bis(trimethyltinyl)-[2,2'-bithiophene]-3,3'-dicarbonitrile (76.68 mg, 141.5 μmol), Pd2(dba)3 (5.18 mg, 5.7 μmol) and P(o-tol)3 (6.89 mg, 22.6 μmol) to a 25 mL Schlenk tube, use redistilled toluene (6 mL) as solvent, freeze-dry three times, and treat the system to be anhydrous and oxygen-free. Heat to about 110 ° C and react for 48 hours. Cool to room temperature, pour the reaction solution into methanol solution (200 mL), let it settle for 10 minutes, filter it, and wash the filter cake with methanol several times. The obtained polymer was wrapped with filter paper, put into a Soxhlet extraction apparatus, and extracted with methanol, acetone, n-hexane, dichloromethane and chloroform respectively. The chloroform component was collected to obtain a yellow solid P5, about 63.21 mg, with a yield of 58.6%. 1 H NMR (400MHz, Chloroform-d) δ9.01(s,1H),8.02(s,1H),8.00(s,1H),7.65(s,2H),7.45(s,1H),3.80(s,2H),3.05(s,2H),0.83(s,9H),-0.04(s,6H).

[0136] Example 12

[0137]

[0138] Synthesis route of polymer P6: Add the polymer P3 (50 mg, 65.6 μmol) obtained by extracting the chloroform component into a 100 mL two-necked bottle, treat the system to be anhydrous and oxygen-free, add chloroform (HPLC, 50 mL) under nitrogen protection, heat to about 80 ° C, react for 10 min, slowly add thionyl chloride (1 mL) chloroform (5 mL) solution to the reaction system, add dropwise, continue to react for 24 h. Cool to room temperature, spin dry the solvent, remove excess thionyl chloride, add chloroform to the reaction system, filter, and wash the filter cake repeatedly with chloroform to obtain a brown-red solid P6, about 33.69 mg, with a yield of 90.1%. 1 HNMR(400MHz,D2O+MeOD)δ9.49(s,1H),8.99(s,1H),8.81(s,1H),8.42(s,1H),8.32(s,1H),5.04(s,2H),3.62(s,2H).

[0139] Example 13

[0140]

[0141] Synthesis route of compound 7: Add compound 6 (300 mg, 424.5 μmol) to a 100 mL Schlenk tube, treat the system to be anhydrous and oxygen-free, add chloroform (HPLC, 50 mL) under nitrogen protection, then slowly drop thionyl chloride (8 mL) in chloroform (10 mL) solution to the reaction system, and continue to react at room temperature for 24 h. Spin dry the solvent, remove excess thionyl chloride, add chloroform to the reaction system, filter, and wash the filter cake repeatedly with chloroform to obtain a light yellow solid 7, about 200.1 mg, with a yield of 91.5%. 1 H NMR (400MHz, D2O) δ9.09 (s, 1H), 8.70 (d, J = 8.6Hz, 1H), 8.41 (d, J = 8.8Hz, 1H), 8.13 (s, 1H), 4.77 (t, J = 6.3Hz, 2H), 3.45-3.28 (m, 2H).

[0142] Embodiment 14

[0143]

[0144] Synthesis route of polymer P2-1: Add compound 7 (30 mg, 58.2 μmol), trans-1,2-bis(tributyltin)ethylene (35.31 mg, 58.2 μmol), Pd2(dba)3 (2.13 mg, 2.3 μmol), P(o-tol)3 (2.84 mg, 9.3 μmol) and CuI (2.22 mg, 11.6 μmol) to a 10 mL Schlenk tube, use dry N-methylpyrrolidone (3 mL) as solvent, freeze-dry for three times, and treat the system to be anhydrous and oxygen-free. Heat to about 110 ° C and react for 48 hours. Cool to room temperature, pour the reaction solution into methanol solution (200 mL), let it settle for 10 minutes, filter, and wash the filter cake with methanol several times. The obtained polymer was wrapped with filter paper and placed in a Soxhlet extraction apparatus. It was extracted with methanol, acetone, n-hexane, dichloromethane, chloroform, chlorobenzene, trifluoroethanol, and hexafluoroisopropanol, respectively. The trifluoroethanol component was collected to obtain a brown-black solid P2-1, about 14.6 mg, with a yield of 65.4% and a number average molecular weight M n =11.2KDa.

[0145] Embodiment 15

[0146]

[0147] Synthesis route of polymer P7: Compound 7 (20 mg, 38.8 μmol), 2,5-bis(2-(2-methoxyethoxy)ethyl)-3,6-bis(5-(tributyltinyl)thiophene-2-yl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione (62.13 mg, 38.8 μmol), Pd(PPh3)4 (1.80 mg, 1.6 μmol) and CuI (0.59 mg, 3.1 μmol) were added to a 10 mL Schlenk tube, and dried N-methylpyrrolidone (4 mL) was used as solvent. Freeze-extraction was performed three times to treat the system with anhydrous and oxygen-free conditions. The temperature was raised to about 135°C and the reaction was carried out for 48 hours. After cooling to room temperature, the reaction solution was poured into a methanol solution (200 mL), and the mixture was allowed to settle for 10 minutes. The mixture was filtered and the filter cake was washed with methanol several times. The obtained polymer was wrapped with filter paper, put into a Soxhlet extraction apparatus, and extracted with methanol, acetone, n-hexane, dichloromethane, chloroform, chlorobenzene, trifluoroethanol, and hexafluoroisopropanol respectively. The trifluoroethanol component was collected to obtain a dark brown solid P7, about 38.58 mg, with a yield of 76.4%.

[0148] Example 16

[0149] The thermoelectric performance of a material is usually described by the thermoelectric figure of merit (ZT), which is described by the following formula:

[0150]

[0151] Where S represents the Seebeck coefficient, σ represents electrical conductivity, κ represents thermal conductivity, and T represents the temperature at which the device is operating. For organic materials, their thermal conductivity is much lower than that of inorganic materials, so the power factor (PF) is often used to describe the thermoelectric properties of organic materials. Taking polymer P2 as an example, we test its electrical conductivity and Seebeck coefficient under doping conditions to characterize its thermoelectric properties. Glass is used as a substrate, and a gold electrode is obtained by photolithography as a test electrode. The substrate is cleaned with acetone, detergent, water, and isopropanol in turn, and then blown dry with nitrogen. Then a 3 mg / mL polymer P2 solution (the solvent is trifluoroethanol and water, and the volume ratio of the two is 1:1) is spin-coated onto the substrate in air. In a glove box (nitrogen atmosphere), the polymer film was sequentially doped with 1-butyl-3-methylimidazolium dicyanamide ([BMIm][N(CN)2]) ionic liquid containing TDAE (the volume ratio of TDAE:[BMIm][N(CN)2] was 1:3000), and then the ionic liquid remaining on the surface was washed off with a mixed solvent of acetonitrile / n-butyl acetate (volume ratio of 1:4). The doping level of the polymer can be controlled by controlling the residence time of the dopant / ionic liquid solution on the film surface. The two ends of the device were placed in a temperature gradient field, and the corresponding thermoelectric potential was tested by the change in the temperature difference between the two ends of the device, and then the Seebeck coefficient was measured, and the conductivity was measured by the four-probe method. The test results are as follows Figure 2-Figure 4 As shown in the figure, with the increase of doping time, the conductivity first increases and then decreases, while the Seebeck coefficient first decreases and then remains almost unchanged. After 5 minutes of doping, the conductivity can reach a maximum of 480S / cm, and the average maximum conductivity is 412S / cm. When doping for 1 minute, the power factor reaches a maximum of 58μW m -1 K -2 The conductivity of the polymer is about 4 times higher than that of the previous polymer. The conductivity and Seebeck coefficient of the polymer were measured on a Lakeshore 1500 semiconductor tester.

[0152] Glass was used as the substrate, and a gold electrode was obtained by photolithography as the test electrode. The substrate was cleaned with acetone, detergent, water and isopropanol in turn, and then dried with nitrogen. Then a 3 mg / mL polymer P4 solution (solvent: trifluoroethanol) was spin-coated onto the substrate in air. In a glove box (nitrogen atmosphere), TDAE was used to vapor-dope the polymer film. The test results are shown in Figure 2. Figure 5-Figure 7 As shown in the figure, with the increase of doping time, the conductivity first increases and then decreases. At about 30 minutes, the conductivity reaches a maximum value of 20.0S / cm. The Seebeck coefficient of the polymer is negative and decreases with the increase of doping degree, achieving 17.2μW m -1 K -2The conductivity and Seebeck coefficient of the polymer were measured on a Lakeshore 1500 semiconductor tester.

[0153] Glass was used as a substrate, and a gold electrode was obtained by photolithography as a test electrode. The substrate was cleaned with acetone, detergent, water, and isopropanol in turn, and then dried with nitrogen. Then a 3 mg / mL polymer P6 solution (solvent: trifluoroethanol) was spin-coated onto the substrate in air. The undoped polymer P6 film had no measured conductivity and was intrinsically non-conductive. In a glove box (nitrogen atmosphere), TDAE was used to vapor-dope the polymer film. After TDAE was used to dope the polymer P6 for 0.5 minutes, the polymer film could obtain 2.81×10 -2 The conductivity of the polymer was 0.51 S / cm. The doping time was further increased. The conductivity reached 0.51 S / cm in about 15 minutes. The conductivity decreased slightly when the doping time was further increased. The conductivity and Seebeck coefficient of the polymer were measured on a Lakeshore 1500 semiconductor tester.

[0154] Embodiment 17

[0155] Organic electrochemical transistor (OECT) devices ( Figure 8 ) and related performance parameters, including transconductance, electron mobility, and volume capacitance, are as follows: using silicon dioxide or glass as a substrate, using photolithography to obtain gold electrodes as source and drain electrodes; the substrate is cleaned with acetone, detergent, water, and isopropanol in turn, and blown dry with nitrogen; the channel is patterned by depositing and etching two layers of polyparaxylene, and then the aqueous solution of the polymer (or small molecule) is spin-coated on the substrate and annealed at different temperatures; then, the sacrificial layer of polyparaxylene is torn off, and the polymer film in the channel is retained. The transfer curve, output curve, and response time of the polymer are tested on a Keithley 4200 semiconductor tester, and the volume capacitance is tested on a BioLogic Science Instruments SP-300 electrochemical workstation, from which the mobility of the material is inferred.

[0156] The following table shows the parameters of organic electrochemical transistor devices made of polymer P2. The performance parameters of devices processed with water / P2 are shown in the attached figure of the specification.

[0157] Table 1

[0158]

[0159] From the transfer curve and output curve of the corresponding polymer P2 Fig. 9 and Fig.10It can be seen that the organic electrochemical transistor device of the water-processed polymer P2 exhibits ideal current amplification characteristics and electron ion transport performance. In addition, Fig.11 The pulse switching test shows that the device has good switching performance and the response speed is faster than that of n-type materials. Fig.12 The transfer and output of the inverter prepared for this material and another p-type material.

[0160] As can be seen from the table, the devices processed by polymer P2 polymerization using water as solvent all show excellent performance, and the performance is currently at the highest value in the field of n-type organic electrochemical transistor materials. We believe that there are two reasons. On the one hand, the final polymer obtained after doping is electrically neutral, and the polymer has high stability in the charged state. More importantly, cationic conjugated polymers have strong electron affinity and usually obtain very high conductivity after doping. On the other hand, cationic conjugated polymers usually have good solubility in highly polar solvents such as water and methanol, which are environmentally friendly and green in the processing of organic semiconductor devices. At the same time, they can avoid large steric hindrances. Substituents hinder the charge transfer between polymer chains, so that the polymer presents a tight stacking mode in the solid state, so that the π-π stacking distance within and between chains is significantly reduced, which can effectively improve the charge transfer capacity between polymer chains. Therefore, the synthesis method and application of cationic conjugated polymers proposed in the present invention have significant effects and important significance in the field of organic semiconductors.

Claims

1. A cationic conjugated polymer, the structure of which is shown in the following formula I: in, Ar 1 and D represent a N-containing heteroaryl group, a N-containing cycloalkenyl group or other conjugated group; Ar and Ar 2 represents an aryl group, a heteroaryl group or other conjugated group; R 6 , R 7 and R 8 The same or different, independently selected from hydrogen, halogen, cyano, nitro, alkyl, alkenyl, alkynyl, alkoxy, polyethylene glycol, ether-containing substituents, halogen-substituted alkyl, aryl, heteroaryl, alkyl-substituted aryl or heteroaryl, can form a ring alone, and / or form a bond with another repeating unit or the terminal group of the polymer; Y - represents anion; n is an integer representing the degree of polymerization of the polymer.

2. The cationic conjugated polymer according to claim 1, characterized in that The alkyl group is a C1-C46 alkyl group; the alkenyl group is a C2-C18 alkenyl group; the alkynyl group is a C2-C18 alkynyl group; the alkoxy group is a C1-C46 alkoxy group; the polyethylene glycol group is a C2-C36 polyethylene glycol group; the ether-containing substituent group is a C1-C3 ether-bonded group; the aryl group is a C6-C30 aryl group; the heteroaryl group is a C2-C26 heteroaryl group; and the N-containing cycloalkenyl group is 1,3-diazacyclopentadiene or 1,2-dihydropyridine.

3. The cationic conjugated polymer according to claim 1, characterized in that The cationic conjugated polymer is selected from one of the following polymers:

4. A method for preparing the cationic conjugated polymer according to claim 1, wherein the reaction formula is as follows: Step 1.1, the monomer represented by formula c and the monomer R*-Ar 2 (R 8 )-R* is polymerized to form a polymer shown in formula d, wherein, R 11 represents an alkoxy group or a silyloxy group, R 9 and R* represent the functional groups required for the monomer to undergo polymerization; Step 1.2, under anhydrous and oxygen-free conditions, using a halogenated organic solvent as a cyclization reaction solvent, controlling the reaction substrate concentration to 3-5 mM, and the reaction temperature to 75-100° C., the repeating unit of the polymer represented by formula d containing a nitrogen heterocyclic ring is subjected to ring closure, so that R 11 The group leaves to obtain a cationic ring system of quaternary nitrogen, generating a cationic conjugated polymer shown in formula I; Among them, R 6 , R 7 , R 8 ,Ar,Ar 1 ,Ar 2 and D as defined in claim 1, Y - It is a halogen anion.

5. The preparation method according to claim 4, characterized in that: The monomer R*-Ar 2 (R 8 )-R* is selected from one of the compounds represented by the following formulas II-1 to II-20: Among them, R 12 represents a hydrogen atom, a halogen atom, a nitro group, an amino group, a cyano group, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, a halogen-substituted alkyl group or a halogen-substituted alkoxy group; R 14 and R 15 are the same or different and are selected from hydrogen, fluorine, cyano, alkyl, halogen-substituted alkyl, phenyl and alkyl-substituted phenyl; b and b' are independently selected from: -S-, -Se-, -O- and -NR 8 —; c and c' are independently selected from: -N=, =N-, -SiR 8 =, =SiR 8 —, —CR 8 = and = CR 8 —; d and d' are independently selected from: -N=, =N-, -SiR 8 =, =SiR 8 —, —CR 8 =, =CR 8 —, =CR 8 R 8 —CR 8 R 8 —, —CR 8 —CR 8 =; e is selected from: —S—, —S(O)—, —S(O)2—, —O—, —SiR 8 R 8 —, —CR 8 R 8 —CR 8 R 8 —, —CR 8 =CR 8 —, —C(O)— and —C(C(CN)2)—; g, h, g', h' are independently selected from: -CR 8 =, =CR 8 —, and —N= and =N—; Among them, R 8 It is hydrogen, halogen, cyano, nitro, alkyl, alkenyl, alkynyl, alkoxy, polyethylene glycol, ether-containing substituents, halogen-substituted alkyl, aryl, heteroaryl, alkyl-substituted aryl or heteroaryl.

6. The preparation method according to claim 5, characterized in that: The monomer R*-Ar 2 (R 8 )-R* is selected from one of the compounds shown in the following structures: Among them, R 12 represents a hydrogen atom, a halogen atom, a nitro group, an amino group, a cyano group, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, a halogen-substituted alkyl group or a halogen-substituted alkoxy group; R 8 It is hydrogen, halogen, cyano, nitro, alkyl, alkenyl, alkynyl, alkoxy, polyethylene glycol, ether-containing substituents, halogen-substituted alkyl, aryl, heteroaryl, alkyl-substituted aryl or heteroaryl.

7. The preparation method according to claim 4, characterized in that: Step 1.1 adopts Suzuki coupling reaction, Stille coupling reaction, Sonogashira coupling reaction, Heck coupling reaction, Kumada coupling reaction, carbon-hydrogen bond activation coupling reaction or Hiyama coupling reaction; Step 1.2 The ring-closing reaction adopts a cyclization reagent of phosphorus oxychloride, sulfonyl chloride, phosgene or sulfuryl chloride, the reaction solvent is selected from one or more of dichloromethane, chlorobenzene, 1,1,2,2,-tetrachloroethane and chloroform, and the reaction time is 12-36 hours.

8. A method for preparing the cationic conjugated polymer according to claim 1, wherein the reaction formula is as follows: Step 2.1, the compound of formula c is subjected to ring closure so that R 11 The group leaves to obtain a quaternary nitrogen cationic ring system, generating a compound shown in formula g; Step 2.2, the monomer represented by formula g and the monomer R*-Ar 2 (R 8 )-R* is polymerized in a polar organic solvent to form a cationic conjugated polymer shown in formula I; in, R 11 represents an alkoxy group or a silyloxy group, R 9 and R* represent the functional groups required for the polymerization reaction of the monomer; R 6 , R 7 , R 8 ,Ar,Ar 1 ,Ar 2 , D and Y - As defined in claim 1.

9. The preparation method according to claim 8, characterized in that: The cyclization reagent used in the ring-closing reaction in step 2.1 is phosphorus oxychloride, sulfonyl chloride, phosgene or sulfuryl chloride, the reaction temperature is 25-150° C., the reaction solvent is selected from one or more of dichloromethane, tetrahydrofuran, acetonitrile, chlorobenzene, 1,1,2,2-tetrachloroethane and chloroform, and the reaction time is 12-36 hours; Step 2.2 adopts Suzuki coupling reaction, Stille coupling reaction, Sonogashira coupling reaction, Heck coupling reaction, Kumada coupling reaction, carbon-hydrogen bond activation coupling reaction or Hiyama coupling reaction, and the reaction solvent is selected from one or more of o-xylene, o-dichlorobenzene, N,N-dimethylformamide, chlorobenzene, N-methylpyrrolidone and dimethyl sulfoxide.

10. The preparation method according to claim 8, characterized in that: The monomer R*-Ar 2 (R 8 )-R* is selected from one of the compounds shown in the following structures: Among them, R 12 represents a hydrogen atom, a halogen atom, a nitro group, an amino group, a cyano group, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, a halogen-substituted alkyl group or a halogen-substituted alkoxy group; R 14 and R 15 are the same or different and are selected from hydrogen, fluorine, cyano, alkyl, halogen-substituted alkyl, phenyl and alkyl-substituted phenyl; b and b' are independently selected from: -S-, -Se-, -O- and -NR 8 —; c and c' are independently selected from: -N=, =N-, -SiR 8 =, =SiR 8 —, —CR 8 = and = CR 8 —; d and d' are independently selected from: -N=, =N-, -SiR 8 =, =SiR 8 —, —CR 8 =, =CR 8 —, =CR 8 R 8 —CR 8 R 8 —, —CR 8 —CR 8 =; e is selected from: —S—, —S(O)—, —S(O)2—, —O—, —SiR 8 R 8 —, —CR 8 R 8 —CR 8 R 8 —, —CR 8 =CR 8 —, —C(O)— and —C(C(CN)2)—; g, h, g', h' are independently selected from: -CR 8 =, =CR 8 —, and —N= and =N—; a and a' are independently selected from: -S-, -Se-, -O- and -NR 8 —; m and m' are independently selected from: -S-, -S(O)-, -S(O)2-, -O-, -NR 8 —,—SiR 8 R 8 —, —CR 8 R 8 —CR 8 R 8 —, —CR 8 =CR 8 —, —C(O)— and —C(C(CN)2)—; n and n' are independently selected from: -N=, =N-, -SiR 8 =, =SiR 8 —,—SiR 8 R 8 —, —CR 8 R 8 —CR 8 R 8 —and—CR 8 =CR 8 —; Among them, R 8 It is hydrogen, halogen, cyano, nitro, alkyl, alkenyl, alkynyl, alkoxy, polyethylene glycol, ether-containing substituents, halogen-substituted alkyl, aryl, heteroaryl, alkyl-substituted aryl or heteroaryl.

11. The preparation method according to claim 10, characterized in that: The monomer R*-Ar 2 (R 8 )-R* is selected from one of the compounds shown in the following structures:

12. Use of the cationic polymer according to any one of claims 1 to 3 as an organic semiconductor material in a photoelectric device or an organic thermoelectric device.

13. The use according to claim 12, characterized in that The optoelectronic device is an organic electrochemical transistor.

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