Use of pi-conjugated organoboron polymers in thin-film organic polymer electronic devices

Abstract

Pi-conjugated organoboron polymers for use in thin-film organic polymer electronic devices. The polymers contain aromatic and or unsaturated repeat units and boron atoms. The vacant p-orbital of the boron atoms conjugate with the pi-conjugated orbital system of the aromatic or unsaturated monomer units extending the pi-conjugation length of the polymer across the boron atoms. The pi-conjugated organoboron polymers are electron-deficient and, therefore, exhibit n-type semiconducting properties, photoluminescence, and electroluminescence. The invention provides thin-film organic polymer electronic devices, such as organic photovoltaic cells (OPVs), organic diodes, organic photodiodes, organic thin-film transistors (TFTs), organic field-effect transistors (OFETs), printable or flexible electronics, such as radio-frequency identification (RFID) tags, electronic papers, and printed circuit elements, organic light-emitting diodes (OLEDs), polymer light-emitting diodes (PLEDs), and energy storage devices employing the pi-conjugated organoboron polymers. In OLED and PLED applications these materials are used as the electron transport layer (ETL) to improve device efficiency. The polymers which exhibit photo- and electroluminescence are also useful as light-emitting material in PLEDs.

1 . A thin film, organic polymer electronic device which comprises at least one active layer containing a first thin film of a pi-conjugated organoboron polymer and at least two electrodes in contact with the active layer.  
     
     
         2 . The device of  claim 1  wherein the first thin film of the pi-conjugated organoboron polymer is 100 angstroms to 10000 angstroms in thickness.  
     
     
         3 . The device of  claim 1  wherein the first thin film of the pi-conjugated organoboron polymer is 100 angstroms to 3000 angstroms in thickness.  
     
     
         4 . The device of  claim 3  that exhibits current rectification or diode-like properties.  
     
     
         5 . The device of  claim 4  wherein the first thin film of a pi-conjugated organoboron polymer emits light under a voltage bias.  
     
     
         6 . The device of  claim 4  wherein the active layer of the device contains a second thin film containing a light-emitting polymer that is not a pi-conjugated organoboron polymer.  
     
     
         7 . The device of  claim 4  wherein the device contains a second thin film containing a light-emitting non-polymeric molecule.  
     
     
         8 . The device of  claim 1  wherein the first thin film comprises a pi-conjugated organoboron polymer blended with a light-emitting non-polymeric molecule.  
     
     
         9 . The device of  claim 1  wherein the first thin film comprises a pi-conjugated organoboron polymer blended with an organic or inorganic conducting or semiconducting material.  
     
     
         10 . The device of  claim 1  wherein the first thin film comprises a p-type conducting or semiconducting polymer blended with a pi-conjugated organoboron polymer.  
     
     
         11 . The device of  claim 1  wherein the first thin film comprises a p-type conducting or semiconducting molecule blended with a pi-conjugated organoboron polymer.  
     
     
         12 . The device of  claim 1  wherein the first thin film comprises inorganic p-type semiconducting particles mixed with a pi-conjugated organoboron polymer.  
     
     
         13 . The device of  claim 12  wherein the inorganic p-type semiconducting particles have at least one dimension less than 1000 angstroms.  
     
     
         14 . The device of  claim 1  wherein the active layer comprises a second thin film of a dielectric material wherein the second thin film is in contact with one or more additional electrodes.  
     
     
         15 . The device of  claim 1  wherein the pi-conjugated organoboron polymer has any of the structures:  
       
         
           
           
               
               
           
         
       
       wherein each R, independent of other R's in the repeating unit, and R 1 , independent of any R's, can be hydrogen, deuterium, a halogen atom, or an organic radical, Ar represents a divalent aromatic radical which may optionally carry one or more other organic radical groups, substituent groups, and/or functional groups described herein and “n”, “m” and “p” are integers representing the number of indicated moieties in a repeating unit or the average degree of polymerization of the polymer.  
     
     
         16 . The device of  claim 1  wherein the pi-conjugated organoboron polymer has the structure:  
       
         
           
           
               
               
           
         
         where:  
         Ar is a divalent radical resulting from the removal of two hydrogen atoms from benzene, naphthalene, diphenyl, pyridine, pyrimidine, triazine, pyrrole, N-alkylpyrroles, N-substituted pyrroles, 3-substituted pyrroles, furan, tetrazole, indole, purine, oxadiazole, quinoxaline, phenazine, N,N′-dialkylphenazines, phenothiazine, N-alkylphenothiazines, carbazole, N-alkylcarbazoles, thiophene, 3-alkylthiophenes, 3-substituted thiophenes, 3,4-disubstituted thiophenes, thienothiophene, substituted thienothiophenes, bithiophene, terthiophene, quaterthiophene, dialkyloxybenzenes, oxadiazole, fluorene, 9,9-dialkylfluorenes and their substituted derivatives;  
         R 1  is any aliphatic or aromatic radical; and  
         n is an integer.  
       
     
     
         17 . The device of  claim 1  wherein the pi-conjugated organoboron polymer has the structure:  
       
         
           
           
               
               
           
         
         where each R, independent of other R's in the repeating unit, and R 1 , independent of any R's, can be hydrogen, deuterium, a halogen atom, or an organic radical, and n, m and p are integer numbers indicating the average degree of polymerization of the polymer or the number of repeat units.  
       
     
     
         18 . An organoboron polymer having the structure:  
       
         
           
           
               
               
           
         
         where Ar is a divalent radical resulting from the removal of two hydrogen atoms from, pyridine, pyrimidine, triazine, pyrrole, N-alkylpyrroles, N-substituted pyrroles, 3-substituted pyrroles, furan, tetrazole, indole, purine, oxadiazole, 1,5-diphenyl-oxadiazole, quinoxaline, phenazine, N,N′-dialkylphenazines, phenothiazine, N-alkylphenothiazines, carbazole, N-alkylcarbazoles, 3,4-disubstituted thiophenes, thienothiophene, substituted thienothiophenes, oxazole, fluorene, 9,9-dialkylfluorenes and their substituted derivatives; R 1 , independent of other R 1  in the repeating unit are hydrogens, deuterium atoms, halogen atoms, linear or branched alkyl radicals which can be optionally substituted with one or more non-hydrogen substituents or functional groups; and n is an integer representing the average degree of polymerization of the polymer.  
       
     
     
         19 . The polymer of  claim 18  wherein Ar is selected from the group consisting of fluorenes, substituted fluorenes and 9,9, dialkylfluorenes.  
     
     
         20 . The polymer of  claim 18  wherein Ar is selected from the group consisting of  
       
         
           
           
               
               
           
         
         wherein R 2  and R 3 , independently of each other, are hydrogens, deuterium atoms, halogen atoms, or linear or branched alkyl radicals, which can be optionally substituted with one or more non-hydrogen substituents or functional groups or R 2  represents an organic group that links two ring positions wherein R 2  can represent multiple independent substituents or functional groups on the rings and m is an integer ranging from 1 to 6.  
       
     
     
         21 . The polymer of claims  20  wherein m is an integer from 1 to 3.  
     
     
         22 . The polymer of claims  20  wherein Ar is  
       
         
           
           
               
               
           
         
       
     
     
         23 . The polymer of  claim 20  wherein R 2  and R 3  are hydrogens, deuteriums or alkyl groups.  
     
     
         24 . An organoboron polymer having structure:  
       
         
           
           
               
               
           
         
         where each R, R 1 , R 2  independent of each other is a hydrogen, deuterium, a halogen atom, or an organic radical, and n, m and p are integer numbers indicating the average degree of polymerization of the polymer or the number of repeat units.  
       
     
     
         25 . An organoboron polymer having the structure:  
       
         
           
           
               
               
           
         
         where R 4  is an optionally substituted saturated or unsaturated organic radical or an aromatic radical;  
         R, independent of other R's in the repeating unit, is hydrogen, deuterium, a halogen atom, a silyl radical, or an organic radical and n is an integer representing the average degree of polymerization of the polymer.  
       
     
     
         26 . The polymer of  claim 22  wherein each R is hydrogen or deuterium.