KR101156630B1 - Alternating copolymers containing dialkoxynaphthalene the electronic devices - Google Patents

Abstract

The present invention includes naphthalene having a dialkoxy substituent which is an organic semiconductor, bithiophene, biselenophene, thienothiophene, selenoselenophene, thiophene vinylenethiophene, selenophene vinyleneselenophene, and thiophene substituted with an alkyl group. Development of unreported alternating copolymers such as thiophene monomers having 1 to 8-mers with or without an alkyl group and vinylene groups substituted or unsubstituted, and the like, are applied to organic electronic devices such as electric field transistors and solar cells. To apply. Alkyl groups are linear and branched alkyl groups of 6 to 24 carbons.

Description

Alternating copolymers containing dialkoxynaphthalene the electronic devices using dialkoxy substituted copolymers having dialkoxy substituents

The present invention includes naphthalene having a dialkoxy substituent which is an organic semiconductor, bithiophene, biselenophene, thienothiophene, selenoselenophene, thiophene vinylenethiophene, selenophene vinyleneselenophene, and thiophene substituted with an alkyl group. The development of unreported alternating copolymers such as thiophene monomers having 1 to 8-mers with or without an alkyl group containing vinylene groups, or unsubstituted thiophenes, and the like, were used in organic electronic devices such as electric field transistors and solar cells. It is applied to an organic semiconductor layer as a channel layer.

The organic thin film transistor is a thin film transistor using an organic semiconductor layer instead of an inorganic (silicon) layer as a channel layer, and the overall structure is not significantly different from a transistor based on silicon. When a voltage is applied to the gate, no current flows due to the insulating film, and an electric field is applied to the semiconductor, thereby acting as a field effect transistor.

The operating principle of the device is that the insulator portion becomes a depletion layer without charge or an accumulation layer with charge, depending on the voltage applied to the gate, thereby controlling the amount of current flowing between the source and the drain. The ratio of this amount of current is called the blink rate and plays an important role in displays such as computer monitors. Organic thin film transistor (OTFT) monitors are bright, bright in color, and fast in response. Plastic can be used as the screen substrate, so the screen can be bent.

However, until now, no alternating copolymers applied to organic electronic devices such as electric field transistors and solar cells have been reported.

It may or may not include naphthalene and bithiophene, biselenophene, thienothiophene, selenoselenophene, thiophene vinylenethiophene, selenophene vinyleneselenophene having an dialkoxy substituent which is an organic semiconductor, or an thiophene substituted with an alkyl group. The present invention intends to develop an alternating copolymer such as thiophene monomers having 1 to 8 monomers which are not substituted or substituted with alkyl groups including vinylene groups.

In addition, this is intended to be applied to organic electronic devices such as electric field transistors, solar cells.

The present invention relates to an alternating copolymer comprising naphthalene having a substituent represented by the following formula (1).

[Formula 1]

In Chemical Formula 1,

R^One To R⁶Independently of each other, hydrogen, (C1-C40) alkyl group, (C3-C40) cycloalkyl group, (C3-C40) heterocycloalkyl group, (C2-C40) alkenyl group, (C6-C50) aryl group, (C6-C50) ) Ar (C1-C40) alkyl group, (C6-C50) heteroaryl group, (C6-C50) heteroar (C1-C30) alkyl group, (C6-C50) ar (C1-C30) alkoxy group, (C1-C40) ) Carbyl group, (C1-C40) hydrocarbyl group, (C1-C40) alkoxy group, (C6-C40) aryloxy group, (C1-C40) alkylcarbonyl group, (C2-C40) alkoxycarbonyl group, (C6 Aryloxycarbonyl group, cyano group (-CN), carbamoyl group (-C (= O) NH₂), Haloformyl group (-C (= O) -X, where X represents a halogen atom), formyl group (-C (= O) -H), isocyano group, isocyanate group, thio Cyanate group, thio isocyanate group, amino group, hydroxyl group, nitro group, trifluoromethyl group (-CF₃), Halogen or silyl, or R^One To R⁶Are independently of each other crosslinked with adjacent carbons of the naphthalene ring and alkylene or alkenylene to form a saturated or unsaturated ring of (C4 ~ C30), the carbon of the saturated or unsaturated ring formed is an oxygen atom, a sulfur atom or Formula -N (R_a)-(Where R_aIs a hydrogen atom or a (C1-C30) alkyl group), and R^One To R⁶Of alkyl, cycloalkyl, heterocycloalkyl, alkenyl, aryl, aralkyl, aralkoxy, carbyl, hydrocarbyl, alkoxy, aryloxy, alkylcarbonyl, alkoxycarbonyl, aryloxycarbonyl, cyano, carbamoyl, Haloformyl, formyl, isocyano, isocyanate, thiocyanate, thioisocyanate, amino, hydroxy, nitro, fluoromethyl or Halogen is independently from each other a (C1-C40) alkyl group, (C3-C40) cycloalkyl group, (C3-C40) heterocycloalkyl group, (C2-C40) alkenyl group, (C6-C50) aryl group, (C6-C50) Ar (C1-C40) alkyl group, (C6-C50) heteroaryl group, (C6-C50) heteroar (C1-C30) alkyl group, (C6-C50) ar (C1-C30) alkoxy group, (C1-C40) Carbyl group, (C1-C40) hydrocarbyl group, (C1-C40) alkoxy group, (C6-C40) aryloxy, (C1-C40) alkylcarbonyl group, (C2-C40) alkoxycarbonyl group, (C6-C40 ) Aryloxycarbonyl group, cyano group (-CN), carbamoyl group (-C (= O) NH₂), Haloformyl group (-C (= O) -X, where X represents a halogen atom), formyl group (-C (= O) -H), isocyano group, isocyanate group, thio May be further substituted with one or more substituents selected from cyanate groups, thioisocyanate groups, amino groups, hydroxy groups, nitro groups, trifluoromethyl groups, halogen groups, silyl groups and acetyl groups;

Ar may be selected from 1 to 8 monomers selected from a (C3 to C40) cycloalkylene group, a (C3 to C40) cycloheteroalkylene group, a (C6 to C50) arylene group and a (C6 to C50) heteroarylene group, The cycloalkylene, cycloheteroalkylene, arylene or heteroarylene is independently of each other (C1-C40) alkyl group, (C3-C40) cycloalkyl group, (C3-C40) heterocycloalkyl group, (C2-C40) alke Neyl group, (C6-C50) aryl group, (C6-C50) ar (C1-C40) alkyl group, (C6-C50) ar (C2-C40) alkenyl group, (C6-C50) heteroaryl group, (C6-C50) Heteroar (C1-C40) alkyl group, (C6-C50) heteroar (C1-C40) alkenyl group, (C6-C50) ar (C1-C30) alkoxy group, (C1-C40) alkoxy group, (C6-C50) C40) aryloxy, linear or branched (C1-C30) alkyl (C6-C40) aryl group, (C1-C40) alkoxy (C6-C40) aryl group, (C3-C40) cycloalkyl (C2-C40) alke It may be further substituted with one or more substituents selected from a nil group and a (C3-C40) heterocycloalkyl (C2-C40) alkenyl group. ;

n is an integer selected from 30 to 8,000.

In addition, Ar is selected from arylene or heteroarylene having the following structure.

In the above structure, X is CR _b R _c , NR _d , O, S or Se, and R _b , R _c and R _d are each independently a (C 1 -C 40) alkyl group, (C 3 -C 40) cycloalkyl group, (C 3- C40) Heterocycloalkyl group, (C2-C40) Alkenyl group, (C6-C50) Aryl group, (C6-C50) Ar (C1-C40) Alkyl group, (C6-C50) Ar (C2-C40) Alkenyl group, ( C6-C50 Heteroaryl group, (C6-C50) Heteroar (C1-C40) Alkyl group, (C6-C50) Heteroar (C1-C40) Alkenyl group, (C6-C50) Ar (C1-C30) Alkoxy group , (C1-C40) alkoxy group, (C6-C40) aryloxy, (C1-C30) alkyl (C6-C40) aryl group, (C1-C40) alkoxy (C6-C40) aryl group, (C3-C40) It may be further substituted with one or more substituents selected from a cycloalkyl (C2 ~ C40) alkenyl group and (C3 ~ C40) heterocycloalkyl (C2 ~ C40) alkenyl group, wherein the arylene or heteroarylene is substituted by the substituent And may form 1 to 8 monomers which are unsubstituted or substituted.

One preferred embodiment may be represented by [Formula 2] and [Formula 3], wherein R has a (C6 ~ C20) alkyl group or (C6 ~ C20) alkoxy group, Ar is bithiophene, biselenophene, thienothiophene , Selenoselenophene, thiophene vinylenethiophene, selenophene vinyleneselenophene, (C6-C24) 1 to 8-mer including or without a substituted thiophene, (C6-C24) containing a vinylene group Thiophene 1 to 8-mers with or without alkyl groups substituted are preferred embodiments.

[Formula 2]

(3)

In addition, the molecular weight of the organic semiconductor compound has a number average molecular weight of 5,000 to 1,000,000, characterized in that it is used as an organic semiconductor layer.

The organic semiconductor compound represented by Chemical Formula 1 according to the present invention is implemented as an organic thin film transistor interposed between the first electrode and the second electrode, and in particular, includes a gate electrode, a gate insulating layer, an organic semiconductor layer, and a source / drain electrode. In an organic thin film transistor, the organic active layer is formed of an organic semiconductor compound represented by Chemical Formula 1 according to the present invention. The organic thin film transistor device according to the present invention may form a top contact structure (not shown) in which a substrate / gate electrode / gate insulating layer / organic semiconductor layer / source-drain electrode are formed in sequence, and as shown in FIG. 1. The substrate 11, the gate electrode 16, the gate insulating layer 12, the source-drain electrodes 14 and 15, and the organic semiconductor layer 13 may be formed in a bottom contact structure, which is not limited thereto. .

In addition, the substrate 11 may be made of glass, polyethylenenaphthalate (PEN), polyethyleneterephthalate (PET), polycarbonate (polycarbonete), polyvinylalcohol, polyacrylate, polyimide ( polyimide), polynorbornene, and polyethersulfone (PES), but are not limited thereto.

In addition, a metal or an organic conductor that is commonly used may be used as the gate electrode 16. Specifically, gold (Au), silver (Ag), aluminum (Al), nickel (Ni), chromium (Cr), and indium may be used. Tin oxide (ITO) may be used, but is not limited thereto.

Further, the gate insulating layer constituting the OTFT device 12 can be used as a large dielectric constant insulators conventionally used, specifically _{Ba 0 .33 Sr 0 .66 TiO 3} (BST), Al 2 O 3, Ta _{2 O 5, La 2 O 5} , Y 2 O 3 and a ferroelectric insulator, PdZr _{0 .33} selected from the group consisting of _{TiO 2 Ti 0 .66 O 3 (} PZT), Bi 4 Ti 3 O 12, BaMgF 4, SrBi 2 (TaNb) ₂ O ₉ , Ba (ZrTi) O ₃ (BZT), BaTiO ₃ , SrTiO ₃ , Bi ₄ Ti ₃ O ₁₂ , SiO ₂ , SiN _x and AlON, an inorganic insulator selected from the group consisting of polyimide ), BCB (benzocyclobutene), parylene (parylene), polyacrylate (polyacrylate), polyvinyl alcohol (poluvinylalcohol) and polyvinyl phenol (polyvinylphenol), such as an organic leading body may be used, but is not limited thereto.

In addition, as the source and drain electrodes 14 and 15, a commonly used metal or an organic conductor may be used. Specifically, gold (Au), silver (Ag), aluminum (Al), nickel (Ni), Chromium (Cr) and indium tin oxide (ITO) may be used, but is not limited thereto.

The organic electronic device of the present invention provides an organic semiconductor layer that can be applied as a new organic semiconductor layer having excellent oxidation stability and excellent reproducibility, and thus, more stable electronic devices can be manufactured.

1 is a cross-sectional view showing a structure of a general organic thin film transistor made of a substrate / gate / insulating layer (source, drain) / semiconductor layer
2 is a diagram showing a differential calorimetry curve of an organic semiconductor compound (PTN-10)
3 is a diagram showing a thermogravimetric analysis curve of an organic semiconductor compound (PTN-10)
4 is a diagram showing UV absorption and PL of an organic semiconductor compound (PTN-10).
5 is a diagram illustrating a transfer curve of an organic thin film transistor employing an organic semiconductor compound (PTN-10) as an organic semiconductor layer.
FIG. 6 is a diagram illustrating an output curve of an organic thin film transistor employing an organic semiconductor compound (PTN-10) as an organic semiconductor layer.
7 shows AFM of an organic semiconductor compound (PTN-10)
8 shows GIXD of an organic semiconductor compound (PTN-10)
9 is a diagram showing a transfer curve of an organic thin film transistor using an organic semiconductor compound (PTN-10) as an organic semiconductor layer with time.
10 is a view showing the change of charge mobility with time of an organic thin film transistor employing an organic semiconductor compound (PTN-10) as an organic semiconductor layer.
FIG. 11 is a diagram illustrating a change in off current with time of an organic thin film transistor employing an organic semiconductor compound (PTN-10) as an organic semiconductor layer.
FIG. 12 is a graph illustrating a change in threshold voltage over time of an organic thin film transistor using an organic semiconductor compound (PTN-10) as an organic semiconductor layer.

The present invention can be more clearly understood by the following examples, which are only intended to illustrate the present invention and are not intended to limit the scope of the invention.

Preparation Example 1 Synthesis of 2,6-Dibromo-1,5-Dihydroxynaphthalene (2,6-Dibromo-l, 5-dihydroxynaphthalene)

10 g of 1,5-dihydroxynaphthalene, 350 mL of glacial acetic acid and 0.3 g of iodine were added to a 500 mL three-necked round flask, and 6.5 mL (2 moles) of bromine was diluted slowly with 25 mL of glacial acetic acid at 80 ° C. Drop. After 4 hours, the solution is cooled, filtered and washed several times with petroleum ether. Recrystallization with glacial acetic acid affords 2,6-dibromo-1,5-dihydroxynaphthalene as the target compound. Yield: 14.5 g (76%); mp 300 ° C. ¹ H-NMR (300 MHz, CDCl ₃ ): 7.72 (d, J = 9.0 Hz, 2H), 7.52 (d, J = 9.0 Hz, 2H), 5.98 (s, 2H)

Preparation Example 2 Synthesis of 5,5'-bis (tributylstannyl) -2,2'-bithiophene (5,5'-bis (tributylstannyl) -2,2'-bithiophene)

10.0 g (60.14 mmol) of 2,2'-bithiophene and 250 mL of dry THF were added to a 500 mL 3-necked round flask and stirred. Cool the flask temperature to -78 ° C using liquid nitrogen and slowly inject 53.0 mL (126.30 mmol) of 2.5 M n-BuLi into the syringe. Stir for 1 hour while maintaining the temperature at 0 ° C. Cool the flask temperature below −78 ° C. with liquid nitrogen and slowly drop 36 mL (126.30 mmol) of SnBu ₃ Cl. After reacting at room temperature for 4 hours, the reaction is terminated with water. Extraction with diethyl ether to remove the solvent, column with hexane and recrystallization with diethyl ether to give the target compound 5,5'-bis (tributylstannyl) -2,2'-bithiophene. . Yield: 44.0 g (98%). ¹ H-NMR (300 MHz, CDCl ₃ , δ / ppm): 7.29 (d, 2H), 7.10 (d, 2H), 0.39 (s, 18H, SnMe ₃ )

Example. Synthesis of naphthalene alternating copolymers with dialkoxy substituents

Example  1.Synthesis of polymers ( PTN -10)

2,6- Dibromo -1,5- Vis - Decyloxy Naphthalene (2,6- Dibromo -1,5- bis - decyloxy -naphthalene)

In a 500 mL three-necked round flask, 10.0 g (31.5 mmol) of 2,6-dibromo-1,5-dihydroxynaphthalene and 5.3 g (94.5 mmol) of KOH were added to 200 mL of anhydrous ethanol and degassed with nitrogen. And slowly add 21.1 g (95.2 mmol) of 1-bromodecane and reflux for 12 hours. The cooled reaction mixture was filtered, washed several times with water and then dried in vacuo and separated into columns using hexane to obtain the desired compound 2,6-dibromo-1,5-bis-decyloxy-naphthalene. Yield: 14.5 g (77%) ¹ H-NMR (300 MHz, CDCl ₃ , δ / ppm): 7.76 (d, J = 9.0 Hz, 2H), 7.62 (d, J = 9.0 Hz, 2H), 4.08 ( t, J = 6.6 Hz, 4H), 1.96 (m, 4H), 1.59 (m, 4H), 1.37 (m, 24H), 0.91 (m, 6H).

Polymer ( PTN Synthesis of -10)

The water inside the 100 mL three-necked round flask was completely removed, followed by 0.33 g (0.54 mmol) of 2,6-dibromo-1,5-bis-decyloxy-naphthalene and 5,5 'in 30 mL of anhydrous toluene. 0.27 g (0.54 mmol) of bis (tributylstannyl) -2,2'-bithiophene was added thereto and dissolved, followed by addition of 0.03 g of Pd (PPh ₃ ) ₄ . After adjusting the temperature to 80 ° C. for 24 hours under a nitrogen stream, 0.05 g of 2-bromonaphthalene was added and reacted for 6 hours. After the reaction has cooled completely, add 250 mL of methanol and filter the solids. Soxhlet was dissolved in toluene, dissolved in chloroform, and then poured into methanol. The solid was filtered and dried to obtain the polymer PTN-10 as a target compound. Yield: 0.3 g (50%), FT-IR (KBr) (cm ^-1 ): 3066 (aromatic CH), 2919-2850 (aliphatic CH), 1346 (aromatic CO), ¹ H-NMR (300 MHz, CDCl) ₃ , δ / ppm): 7.91 (d, 1H), 7.82 (d, 1H), 7.61 (d, 1H), 7.31 (d, 1H), 3.99 (s, 2H), 2.09 (s, 2H), 1.30 (t, 14H), 0.90 (d, 3H).

Example  2. Synthesis of Polymer PTN -12)

Synthesis of 2,6-Dibromo-1,5-bis-dodecyloxy-naphthalene

In a 500 mL three-necked round flask, 10.0 g (31.5 mmol) of 2,6-dibromo-1,5-dihydroxynaphthalene and 5.3 g (94.5 mmol) of KOH were added to 200 mL of anhydrous ethanol and degassed with nitrogen. And slowly adding 23.8 g (95.2 mmol) of 1-bromododecane and refluxing for 12 h. The cooled reaction mixture was filtered, washed several times with water, dried in vacuo and separated into columns using hexane to obtain the desired compound 2,6-dibromo-1,5-bis-dodecyloxy-naphthalene. Yield: 15.2 g (74%) ¹ H-NMR (300 MHz, CDCl ₃ , δ / ppm): 7.76 (d, J = 9.0 Hz, 2H), 7.62 (d, J = 9.0 Hz, 2H), 4.08 ( t, J = 6.6 Hz, 4H), 1.96 (m, 4H), 1.59 (m, 4H), 1.38 (m, 32H), 0.90 (m, 6H).

Synthesis of Polymer (PTN-12)

The water inside the 100 mL three-necked round flask was completely removed and then 0.35 g (0.54 mmol) of 2,6-dibromo-1,5-bis-dodecyloxy-naphthalene and 5,5 'in 30 mL of anhydrous toluene. 0.27 g (0.54 mmol) of bis (tributylstannyl) -2,2'-bithiophene was added thereto and dissolved, followed by addition of 0.03 g of Pd (PPh ₃ ) ₄ . After adjusting the temperature to 80 ° C. for 24 hours under a nitrogen stream, 0.05 g of 2-bromonaphthalene was added and reacted for 6 hours. After the reaction has cooled completely, add 250 mL of methanol and filter the solids. Soxhlet was dissolved in toluene, dissolved in chloroform, and then poured into methanol. The solid was filtered and dried to obtain the polymer PTN-12 as a target compound. Yield: 0.3 g (48%), FT-IR (KBr) (cm ^-1 ): 3050 (aromatic CH), 2910-2850 (aliphatic CH), 1350 (aromatic CO), ¹ H-NMR (300 MHz, CDCl) ₃ , δ / ppm): 7.91 (d, 1H), 7.82 (d, 1H), 7.61 (d, 1H), 7.31 (d, 1H), 3.99 (s, 2H), 2.09 (s, 2H), 1.30 (t, 18 H), 0.90 (d, 3 H).

Example 3 Organic Semiconductor Devices of Naphthalene Alternating Copolymers Having a dialkoxy Substituent

The OTFT device was fabricated in a top-contact manner, using 300 nm n-doped silicon as a gate and SiO ₂ as an insulator. Surface treatment was performed using a piranha cleaning solution (H ₂ SO ₄ : 2H ₂ O ₂ ) and then the surface was treated using Adrich's OTS (octadecyltrichlorosilane) and SAM (Self Assemble Monolayer). The organic semiconductor layer was coated with 0.7 wt% chloroform solution using a spin-coater for 1 minute at 2000 rpm. The thickness of the organic semiconductor layer was 45 nm using a surface profiler (Alpha Step 500, Tencor). Gold used as the source and drain was deposited to a thickness of 50 nm at 1 A / s. The channel is 1000 μm long and 2000 μm wide. The measurement of OTFT characteristics was done using Keithley 2400 and 236 source / measure units.

The charge mobility was obtained from (S _SD ) ^1/2 and V _G as variables from the saturation region current equation and obtained from the slope.

Where I _SD is the source-drain current, μ or μ _FET is the charge transfer, C ₀ is the oxide capacitance, W is the channel width, L is the channel length, V _G is the gate voltage, and V is _T is the threshold voltage.

In addition, the cutoff leakage current I _off is a current flowing in the off state, and is determined as the minimum current in the off state in the current ratio.

1 is a cross-sectional view showing a structure of a general organic thin film transistor made of a substrate / gate / insulating layer (source, drain) / semiconductor layer, and FIG. 2 is a thermal characteristic of an organic semiconductor compound (PTN-10) according to Example 1 The organic semiconductor material synthesized by the curve showing the characteristics showing the high crystallinity, Figure 3 is an organic semiconductor synthesized in a curve showing the thermal properties of the organic semiconductor compound (PTN-10) according to Example 1 Is a diagram showing that no decomposition is observed even at 350 ° C or higher. In addition, Figure 4 is a view showing the characteristic that the organic semiconductor compound (PTN-10) according to Example 1 increases the intermolecular pi bond by moving to a long wavelength region in the solution state and the film, Figure 5 is according to Example 1 In the device fabricated in Example 3 using the organic semiconductor compound (PTN-10), a transfer curver showing semiconductor characteristics shows a charge mobility of 0.02 cm ² / Vs and a flashing ratio of about 10 ⁵ . A diagram showing an output curve showing semiconductor characteristics in the device fabricated in Example 3 using the organic semiconductor compound (PTN-10) according to Example 1. 7 is a view showing that the organic semiconductor material synthesized by Example 1 by the surface AFM image in the device of Example 3 using the organic semiconductor compound (PTN-10) according to Example 1 is a material having excellent crystallinity. 8 is a view showing that the organic semiconductor material synthesized in Example 1 by the GIXD image of the device of Example 3 using the organic semiconductor compound (PTN-10) according to Example 1 is a material having excellent crystallinity. 9 is a view showing a material having excellent reproducibility due to no change in the transfer curve after a lapse of time in the device of Example 3 using the organic semiconductor compound (PTN-10) according to Example 1. FIG. In addition, FIG. 10 is a view showing that there is no change in charge mobility even after elapse of time in the device of Example 3 using the organic semiconductor compound (PTN-10) according to Example 1, and FIG. 11 according to Example 1 Using the organic semiconductor compound (PTN-10) is a diagram showing that there is no change in the off current even after the time in the Example 3 device, Figure 12 using the organic semiconductor compound (PTN-10) according to Example 1 Example 3 This diagram shows that there is no change in the threshold sum even after elapse of time in the device. As shown in FIGS. 9, 10, 11, and 12, the synthesized organic semiconductor material proves that the material has excellent oxidation stability and excellent reproducibility.

<Explanation of symbols for the main parts of the drawings>
11 substrate 12 insulator
13: organic semiconductor layer (channel material) 14: source
15: drain 16: gate

Claims (6)

delete delete An alternating copolymer represented by the following formula (2).
(2)

[In Formula 2, R is a (C10 ~ C20) alkoxy group, Ar is a bithiophene, biselenophene, thienothiophene, selenoselenophene, thiophenevinylenethiophene, selenophenevinyleneselenophene, (C6 Or a (C6-C24) alkyl group comprising a vinylene group or a substituted or unsubstituted thiophene 1 to 8-mer.
An organic semiconductor layer made of the alternating polymer of claim 3.
An organic electronic device comprising the organic semiconductor layer of claim 4.
6. The method of claim 5,
The electronic device is any one selected from an electric field transistor or a solar cell.

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