Electrochromic polymers containing pyrrole derivatives and thiophenes

Abstract

A new electrochromic polymer that is yellow or orange or red in the neutral state and a method of forming the new electrochromic polymer are disclosed. The disclosed electrochromic polymer has a low onset oxidation potential and a high optical contrast in the wavelength range of 400 nm to 550 nm.

Description

Technical Field

[0001] This disclosure relates to an electrochromic polymer containing pyrrole derivatives and thiophene, which is yellow, orange, or red in a neutral state, and a method for synthesizing the electrochromic polymer. Background Technology

[0002] Electrochromic polymers in their neutral yellow or red state are crucial for achieving full-color toning because the subtractive primary colors of Cyan-Magenta-Yellow (CMY) and Red-Yellow-Blue (RYB) require both yellow and red. However, most traditional yellow or red electrochromic polymers (ECPs) are electrochemically unstable under repeated color-transmission switching. High-energy-absorbing polymers lack cycle durability due to the high oxidation potential required for their fading process. Therefore, electrochromic polymers in yellow, orange, or red with lower oxidation potentials and higher optical contrast are needed. Summary of the Invention

[0003] This disclosure relates to an electrochromic polymer comprising the following formula:

[0004] [(Tr) a -(Ar1) b -(Ar2) c -(Ar3) d ] n ,

[0005] in,

[0006] Tr is a trimer based on pyrrole or pyrrole derivatives, which has the following formula:

[0007]

[0008] Ar1 is

[0009] Ar2 is

[0010] Ar3 is

[0011] n is a positive integer; a is a positive integer; b, c, and d are positive integers, and the ratio of a to the sum of b, c, and d is between 0.1 and 4 (inclusive); R1-R 13 Each is independently selected from, but not limited to: hydrogen, C1-C 30 Alkyl, C2-C 30 alkenyl, C2-C 30 alkynyl group, C2-C 30 Alkyl carbonyl, C1-C 30 Alkoxy, C3-C30 Alkoxyalkyl, C2-C 30 alkoxycarbonyl, C4-C 30 alkoxycarbonylalkyl, C1-C 30 Alkyl thio, C1-C 30 amino carbonyl, C4-C 30 aminoalkyl, C1-C 30 Alkylamino, C1-C 30 Alkyl sulfonyl, C3-C 30 alkylsulfonylalkyl, C6-C 18 Aryl, C3-C 15 cycloalkyl, C3-C 30 Cycloalkylamino, C5-C 30 Cycloalkylalkylamino, C5-C 30 cycloalkylalkyl, C5-C 30 Cycloalkylalkoxy, C1-C 12 Heterocyclic groups, C1-C 12 Heterocyclic radicals, C3-C 30 Heterocyclic alkoxy, C1-C 30 Heterocyclic alkoxy, C1-C 30 Heterocyclic amino groups, C5-C 30 Heterocyclic alkylamino, C2-C 12 Heterocyclic carbonyl, C3-C 30 Heterocyclic alkyl, C1-C 13 heteroaryl, or C3-C 30 Heteroarylalkyl.

[0012] In some embodiments, the onset oxidation potential of the electrochromic polymer is below 0.6V (using Ag / AgCl as a reference electrode).

[0013] In some implementations, the electrochromic polymer exhibits an optical contrast greater than 50% at its maximum absorption wavelength.

[0014] In some embodiments, the maximum absorption wavelength of the electrochromic polymer is 400 nm to 550 nm (inclusive).

[0015] In some implementations, Tr is selected from one of the following formulas:

[0016]

[0017] Furthermore, Ar1, Ar2, and Ar3 are each independently selected from one of the following formulas:

[0018]

[0019] X is S or O; R 51 -R59 Each is independently selected from, but not limited to: hydrogen, C1-C 30 Alkyl, C2-C 30 alkenyl, C2-C 30 alkynyl group, C2-C 30 Alkyl carbonyl, C1-C 30 Alkoxy, C3-C 30 Alkoxyalkyl, C2-C 30 alkoxycarbonyl, C4-C 30 alkoxycarbonylalkyl, C1-C 30 Alkyl thio, C1-C 30 amino carbonyl, C4-C 30 aminoalkyl, C1-C 30 Alkylamino, C1-C 30 Alkyl sulfonyl, C3-C 30 alkylsulfonylalkyl, C6-C 18 Aryl, C3-C 15 cycloalkyl, C3-C 30 Cycloalkylamino, C5-C 30 Cycloalkylalkylamino, C5-C 30 cycloalkylalkyl, C5-C 30 Cycloalkylalkoxy, C1-C 12 Heterocyclic groups, C1-C 12 Heterocyclic radicals, C3-C 30 Heterocyclic alkoxy, C1-C 30 Heterocyclic alkoxy, C1-C 30 Heterocyclic amino groups, C5-C 30 Heterocyclic alkylamino, C2-C 12 Heterocyclic carbonyl, C3-C 30 Heterocyclic alkyl, C1-C 13 heteroaryl, or C3-C 30 Heteroarylalkyl.

[0020] In some implementations, Tr is selected from one of the following formulas:

[0021]

[0022] Furthermore, Ar1, Ar2, and Ar3 are each independently selected from one of the following formulas:

[0023]

[0024] R 61 -R 69 Each is independently selected from, but not limited to: hydrogen, C1-C 30 Alkyl, C2-C 30 alkenyl, C2-C 30alkynyl group, C2-C 30 Alkyl carbonyl, C1-C 30 Alkoxy, C3-C 30 Alkoxyalkyl, C2-C 30 alkoxycarbonyl, C4-C 30 alkoxycarbonylalkyl, C1-C 30 Alkyl thio, C1-C 30 amino carbonyl, C4-C 30 aminoalkyl, C1-C 30 Alkylamino, C1-C 30 Alkyl sulfonyl, C3-C 30 alkylsulfonylalkyl, C6-C 18 Aryl, C3-C 15 cycloalkyl, C3-C 30 Cycloalkylamino, C5-C 30 Cycloalkylalkylamino, C5-C 30 cycloalkylalkyl, C5-C 30 Cycloalkylalkoxy, C1-C 12 Heterocyclic groups, C1-C 12 Heterocyclic radicals, C3-C 30 Heterocyclic alkoxy, C1-C 30 Heterocyclic alkoxy, C1-C 30 Heterocyclic amino groups, C5-C 30 Heterocyclic alkylamino, C2-C 12 Heterocyclic carbonyl, C3-C 30 Heterocyclic alkyl, C1-C 13 heteroaryl, or C3-C 30 Heteroarylalkyl.

[0025] In some embodiments, the electrochromic polymer has the following formula:

[0026]

[0027]

[0028]

[0029] A method for forming the electrochromic polymer is also provided. The method includes: preparing a thiophene trimer unit based on pyrrole or a pyrrole derivative; and preparing the electrochromic polymer by polymerizing the thiophene trimer unit based on pyrrole or a pyrrole derivative with a thiophene unit.

[0030] A method for forming pyrrole or pyrrole derivatives is also provided. This method involves contacting a diketone with a primary amine in the presence of hexafluoro-2-propanol.

[0031] A method for forming a diketone derivative is also provided. This method includes contacting a lithium-ionized thiophene derivative with N1,N4-dimethoxy-N1,N4-dimethylbutanediamide.

[0032] This disclosure also relates to an apparatus comprising the disclosed electrochromic polymer. Attached Figure Description

[0033] Certain features of the various embodiments of this technology are specifically set forth in the appended claims. The features and advantages of this technology can be better understood by referring to the following detailed description and the accompanying drawings, which illustrate illustrative embodiments utilizing the principles of the invention. For the purpose of illustrating the invention, the accompanying drawings show various aspects of one or more embodiments of the invention. However, it should be understood that the invention is not limited to the precise arrangements and means shown in the drawings.

[0034] Figure 1 CV data for an example electrochromic polymer (ECP) - yellow 1 film according to an example embodiment.

[0035] Figure 2 The absorption spectra of an ECP-Yellow 1 film in its colored and faded states according to an example embodiment are shown.

[0036] Figure 3 The switching dynamics of an ECP-yellow 1 thin film at 455 nm according to an example embodiment.

[0037] Figure 4 CV data for an example ECP-yellow 2 film according to an example implementation.

[0038] Figure 5 The absorption spectra of an ECP-Yellow 2 film in its colored and faded states according to an example embodiment are shown.

[0039] Figure 6 The switching dynamics of an ECP-yellow 2 thin film at 455 nm according to an example embodiment.

[0040] Figure 7 CV data for an example ECP-Red 1 film according to an example implementation.

[0041] Figures 8(A)-(B) are images of the ECP-Red 1 film according to an example embodiment in a colored state (Figure 8(A)) and a faded state (Figure 8(B)).

[0042] Figure 9 The absorption spectra of an ECP-Red 1 film according to an example embodiment are shown in the colored and faded states.

[0043] Figure 10 The switching dynamics of an ECP-Red 1 thin film at 550 nm according to an example embodiment. Detailed Implementation

[0044] In the following description, certain specific details are set forth to provide a thorough understanding of the various embodiments of the invention. However, those skilled in the art will understand that the invention can be practiced without these details. Furthermore, while various embodiments of the invention have been disclosed herein, many adjustments and modifications can be made within the scope of the invention based on common knowledge of those skilled in the art. These modifications include substitutions for known equivalents of any aspect of the invention in order to achieve the same results in substantially the same manner.

[0045] Unless the context otherwise requires, the word “comprising” and its variations, such as “including” and “contains”, shall be understood in this specification and claims to have an open, inclusive meaning, i.e., “including but not limited to”. Throughout the specification, descriptions of numerical ranges are intended as a simplified notation, referring individually to each individual numerical value falling within that range, including the numerical value defining the range, and each individual numerical value is incorporated herein as it is individually enumerated. Furthermore, unless the context explicitly requires otherwise, the singular forms “a,” “an,” and “the” include plural references to objects.

[0046] The reference to "one embodiment" or "an embodiment" in this specification means that a specific feature, structure, or characteristic associated with that embodiment is included in at least one embodiment of the invention. Therefore, the phrases "in one embodiment" or "in an embodiment" appearing in various places throughout the specification do not necessarily refer to the same embodiment, but may in some cases. Furthermore, specific features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0047] Embodiments of this disclosure relate to electrochromic polymers (ECPs). Each ECP has the following formula:

[0048] [(Tr) a -(Ar1) b -(Ar2) c -(Ar3) d ] n ,

[0049] in,

[0050] Tr is a trimer based on pyrrole or pyrrole derivatives, which has the following formula:

[0051]

[0052] Ar1 is

[0053] Ar2 is

[0054] Ar3 is

[0055] R1-R 13 Each is independently selected from, but not limited to: hydrogen, C1-C 30 Alkyl, C2-C 30 alkenyl, C2-C 30 alkynyl group, C2-C 30 Alkyl carbonyl, C1-C 30 Alkoxy, C3-C 30 Alkoxyalkyl, C2-C 30 alkoxycarbonyl, C4-C 30 alkoxycarbonylalkyl, C1-C 30 Alkyl thio, C1-C 30 amino carbonyl, C4-C 30 aminoalkyl, C1-C 30 Alkylamino, C1-C 30 Alkyl sulfonyl, C3-C 30 alkylsulfonylalkyl, C6-C 18 Aryl, C3-C 15 cycloalkyl, C3-C 30 Cycloalkylamino, C5-C 30 Cycloalkylalkylamino, C5-C 30 cycloalkylalkyl, C5-C 30 Cycloalkylalkoxy, C1-C 12 Heterocyclic groups, C1-C 12 Heterocyclic radicals, C3-C 30 Heterocyclic alkoxy, C1-C 30 Heterocyclic alkoxy, C1-C 30 Heterocyclic amino groups, C5-C 30 Heterocyclic alkylamino, C2-C 12 Heterocyclic carbonyl, C3-C 30 Heterocyclic alkyl, C1-C 13 heteroaryl, or C3-C 30 Heteroarylalkyl; n is an integer greater than 0; a is an integer greater than 0; b, c, and d are integers not less than 0, and the ratio of a to the sum of b, c, and d is from 0.1 to 4 (inclusive). In some embodiments, the ratio of a to the sum of b, c, and d is from 0.1 to 2 (inclusive). In some embodiments, the ratio of a to the sum of b, c, and d is from 0.1 to 1 (inclusive).

[0056] In some embodiments, the pyrrole-based or pyrrole derivative-based thiophene trimer unit comprises a central pyrrole or pyrrole derivative unit and two thiophene units at either end of the pyrrole or pyrrole derivative unit. The ECP in this disclosure is formed by polymerizing the pyrrole-based or pyrrole derivative-based thiophene trimer unit with thiophene units. Although three types of thiophene units polymerized with the pyrrole or pyrrole derivative-based thiophene trimer unit are listed in the above formula, it is possible and considered in this disclosure for more or fewer than three types of thiophene units polymerized with the pyrrole or pyrrole derivative-based thiophene trimer unit. The polymerization can be random polymerization or alternating polymerization comprising repeating units having a specific sequence. In some embodiments, the repeating unit of the disclosed ECP comprises one pyrrole or pyrrole derivative-based thiophene trimer unit. In some embodiments, the disclosed ECP comprises more than one mutually conjugated pyrrole or pyrrole derivative-based thiophene trimer unit. In some embodiments, the ECP of this disclosure comprises a plurality of pyrrole-based or pyrrole derivative-based thiophene trimer units spaced / separated by at least one thiophene unit.

[0057] The ECP of this disclosure exhibits a yellow, orange, or red color in its active state and is nearly colorless in its oxidized state. Due to the introduction of pyrrole or pyrrole derivative units, the ECP of this disclosure has the advantage of a low onset oxidation potential, which generally leads to excellent cycle durability.

[0058] The electrochromic polymers of this disclosure have an onset oxidation potential of less than 0.6 V (with Ag / AgCl as a reference electrode). In some embodiments, the onset oxidation potential of the electrochromic polymers is less than 0.4 V (relative to Ag / AgCl).

[0059] The electrochromic polymers of this disclosure have a maximum absorption wavelength of 400 nm to 550 nm (inclusive). In some embodiments, the electrochromic polymer is yellow in the neutral state. In some embodiments, the electrochromic polymer is orange in the neutral state. In some embodiments, the electrochromic polymer is red in the neutral state.

[0060] The electrochromic polymer of this disclosure has an optimal optical contrast ratio of over 50% at its maximum absorption wavelength. In some embodiments, the optimal optical contrast ratio of the electrochromic polymer at its maximum absorption wavelength is over 60%. In some embodiments, the optimal optical contrast ratio of the electrochromic polymer at its maximum absorption wavelength may be over 70%, 80%, 90%, 95%, or up to 100%, or between any two of the above figures.

[0061] In some embodiments, the repeating unit of the ECP comprises one pyrrole-based or pyrrole derivative-based thiophene trimer unit and one thiophene unit. In some embodiments, the repeating unit of the ECP comprises one pyrrole-based or pyrrole derivative-based thiophene trimer unit and three thiophene units. In some embodiments, the repeating unit of the ECP comprises one pyrrole-based or pyrrole derivative-based thiophene trimer unit and five thiophene units. In some embodiments, the repeating unit of the ECP comprises one pyrrole-based or pyrrole derivative-based thiophene trimer unit and ten thiophene units. In some embodiments, the repeating unit of the ECP comprises more than one pyrrole-based or pyrrole derivative-based thiophene trimer unit and thiophene units.

[0062] In some implementations, Tr is selected from one of the following formulas:

[0063]

[0064] Furthermore, Ar1, Ar2, and Ar3 are each independently selected from one of the following formulas:

[0065]

[0066] X is S or O; R 51 -R 59 Each is independently selected from, but not limited to: hydrogen, C1-C 30 Alkyl, C2-C 30 alkenyl, C2-C 30 alkynyl group, C2-C 30 Alkyl carbonyl, C1-C 30 Alkoxy, C3-C 30 Alkoxyalkyl, C2-C 30 alkoxycarbonyl, C4-C 30 alkoxycarbonylalkyl, C1-C 30 Alkyl thio, C1-C 30 amino carbonyl, C4-C 30 aminoalkyl, C1-C 30 Alkylamino, C1-C 30 Alkyl sulfonyl, C3-C 30 alkylsulfonylalkyl, C6-C 18 Aryl, C3-C 15 cycloalkyl, C3-C 30 Cycloalkylamino, C5-C 30 Cycloalkylalkylamino, C5-C 30 cycloalkylalkyl, C5-C 30 Cycloalkylalkoxy, C1-C 12 Heterocyclic groups, C1-C 12 Heterocyclic radicals, C3-C 30Heterocyclic alkoxy, C1-C 30 Heterocyclic alkoxy, C1-C 30 Heterocyclic amino groups, C5-C 30 Heterocyclic alkylamino, C2-C 12 Heterocyclic carbonyl, C3-C 30 Heterocyclic alkyl, C1-C 13 heteroaryl, or C3-C 30 Heteroarylalkyl.

[0067] In some embodiments, all X are O, the thiophene unit includes a propylene dioxythiophene (ProDOT) unit or an ethylene dioxythiophene (EDOT) unit, and Tr is selected from one of the following formulas:

[0068]

[0069]

[0070] Furthermore, Ar1, Ar2, and Ar3 are each independently selected from one of the following formulas:

[0071]

[0072] R 61 -R 69 Each is independently selected from, but not limited to: hydrogen, C1-C 30 Alkyl, C2-C 30 alkenyl, C2-C 30 alkynyl group, C2-C 30 Alkyl carbonyl, C1-C 30 Alkoxy, C3-C 30 Alkoxyalkyl, C2-C 30 alkoxycarbonyl, C4-C 30 alkoxycarbonylalkyl, C1-C 30 Alkyl thio, C1-C 30 amino carbonyl, C4-C 30 aminoalkyl, C1-C 30 Alkylamino, C1-C 30 Alkyl sulfonyl, C3-C 30 alkylsulfonylalkyl, C6-C 18 Aryl, C3-C 15 cycloalkyl, C3-C 30 Cycloalkylamino, C5-C 30 Cycloalkylalkylamino, C5-C 30 cycloalkylalkyl, C5-C 30 Cycloalkylalkoxy, C1-C 12 Heterocyclic groups, C1-C 12 Heterocyclic radicals, C3-C 30Heterocyclic alkoxy, C1-C 30 Heterocyclic alkoxy, C1-C 30 Heterocyclic amino groups, C5-C 30 Heterocyclic alkylamino, C2-C 12 Heterocyclic carbonyl, C3-C 30 Heterocyclic alkyl, C1-C 13 heteroaryl, or C3-C 30 Heteroarylalkyl.

[0073] This disclosure also relates to a method for forming the electrochromic polymer of this disclosure. The method includes: preparing a thiophene trimer unit based on pyrrole or a pyrrole derivative, and preparing the ECP by polymerizing the trimer unit with the thiophene unit. The polymerization can be random polymerization or alternating polymerization comprising repeating units having a specific sequence.

[0074] This disclosure also relates to methods for forming diketone derivatives. The method includes contacting a lithium-ionized thiophene derivative with N1,N4-dimethoxy-N1,N4-dimethylbutanediamide. This disclosure also relates to methods for forming pyrrole or pyrrole derivatives. The method includes using hexafluoro-2-propanol as a solvent and a primary amine to circulate the diketone.

[0075] Implementation

[0076] Implementation Method 1 - A yellow electrochromic polymer (ECP-Yellow 1) formed by alternating polymerization.

[0077] In one embodiment, the electrochromic polymer (ECP-Yellow 1) has the following formula:

[0078]

[0079] ECP-Yellow 1 was synthesized by preparing a pyrrole derivative-based thiophene trimer unit and then polymerizing this pyrrole derivative-based thiophene trimer unit with a propylene dioxythiophene (ProDOT) unit. The detailed method includes the following steps:

[0080] Step 1-1: Prepare the diketone derivative product (compound 3) through the following reaction:

[0081]

[0082] In a Schlenk tube, 2.8 g (2.6 eq.) of propylene dioxothiophene (ProDOT) (compound 2) was added. The tube was kept under vacuum for approximately 15 minutes, then purged with N2. This process was repeated three times. Then, 10 mL of anhydrous tetrahydrofuran (THF) was added to the tube using a syringe. The solution was kept at -78°C, and then 2.5 mL of nBuLi solution (2.5 M in hexane) was slowly added to the tube at -78°C over 20–30 minutes. The solution was slowly heated to 0°C and reacted for 30 minutes, then cooled again to -78°C. N1,N4-dimethoxy-N1,N4-dimethylbutanediamide (compound 1) was dissolved in 3 mL of dry THF and then slowly added to the Schlenk tube at -78°C over 30–50 minutes. The solution was reacted at -78°C for 2 hours, then heated to room temperature. The reaction was quenched with acetic acid and water, and the organic product was extracted with EtOAc. The organic product was dried and vacuum-sealed to remove residual solvent. The resulting mixture was purified by silica gel chromatography to give the diketone derivative product (compound 3, yield ~80%).

[0083] Steps 1-2: Preparation of thiophene trimers based on pyrrole derivatives (compound 4)

[0084]

[0085] In a flask, diketone compound 3 (400 mg, 1 eq.), 1-hexylamine (126 mg, 3 eq.), propionic acid (10 mg, 0.3 eq.), and 4 mL of anhydrous toluene were added. The mixture was bubbled with nitrogen for 10 min to remove air. The mixture was then heated to 110 °C under nitrogen and reacted for 12 h. The mixture was cooled to room temperature and washed with water. The organic phase was collected, and the remaining solvent was removed by rotary evaporation. The resulting mixture was purified by silica gel chromatography to give thiophene trimer based on pyrrole derivatives, compound 4 (yield ~80%-90%).

[0086] Steps 1-3: Preparation of ECP-Yellow 1 by alternating polymerization

[0087]

[0088] In a Schlenk tube, propylenedioxothiophene-2Br (ProDOT-2Br, compound 5, 1.0 eq.), compound 4 (1.0 eq.), K₂CO₃ (2.6 eq.), PivOH (0.3 eq.), and Pd(OAc)₂ (0.02 eq.) were added. The tube was kept under vacuum for about 15 minutes, then purged with N₂. This process was repeated three times. Then, dimethylacetamide (DMAc), a solvent degassed by nitrogen, was added to the tube, and the reaction was carried out at 120 °C for 12 hours under nitrogen. The hot reaction mixture was transferred to a 1:1 mixture of CH₃OH and 1M HCl with stirring. The mixture was filtered to give a solid. The solid was dissolved in chloroform and washed with 1M HCl solution. The organic phase was concentrated and precipitated with CH₃OH. The mixture was filtered and dried to give ECP-yellow 1. The yield was about 80%–100%.

[0089] The obtained ECP-Yellow 1 was dissolved in chloroform at a concentration of 22 mg / ml. The chloroform solution of ECP-Yellow 1 was spin-coated onto an ITO-coated glass substrate. The properties of the resulting ECP-Yellow 1 film were tested in a three-electrode system using Ag / AgCl as the reference electrode, 1M LiPF6 / PC as the electrolyte, and a Pt wire as the counter electrode. Figure 1 As shown, the ECP-Yellow 1 film has a low initial oxidation potential of 0.52V (relative to Ag / AgCl). Furthermore, this electrochromic polymer exhibits a yellow color in its colored state with maximum absorbance at 455nm, and in its faded state, it shows low absorbance in the visible light range (350nm-800nm) (e.g., ...). Figure 2 As shown). The optimal optical contrast at 455nm is as high as 66% (e.g., Figure 3 (As shown).

[0090] Implementation Method 2 - Yellow electrochromic polymer (ECP-Yellow 2) formed by alternating polymerization

[0091] In one embodiment, the electrochromic polymer (ECP-Yellow 2) has the following formula:

[0092]

[0093] ECP-Yellow 2 is synthesized by preparing pyrrole derivative-based thiophene trimer units, followed by polymerization of these units with ethylene dioxythiophene (EDOT) units. The detailed method includes the following steps:

[0094] Step 2-1: Preparation of the diketone derivative product (compound 3)

[0095] Same as step 1-1.

[0096] Step 2-2: Preparation of thiophene trimer based on pyrrole derivative (compound 4)

[0097] Same as steps 1-2.

[0098] Steps 2-3: Preparation of ECP-Yellow 2 by alternating polymerization

[0099]

[0100] The reaction was the same as in steps 1-3, except that 3,4-ethylenedioxythiophene-2Br (EDOT-2Br) compound 6 (1.0 eq.), pyrrole derivative-based thiophene trimer compound 4 (1.0 eq.), K2CO3 (2.6 eq.), PivOH (0.3 eq.) and Pd(OAc)2 (0.02 eq.) were added to the Schlenk tube to carry out the reaction.

[0101] The obtained ECP-Yellow 2 was dissolved in chloroform at a concentration of 30 mg / ml. The ECP-Yellow 2 chloroform solution was spin-coated onto an ITO-coated glass substrate. The properties of the obtained ECP-Yellow 2 film were tested in a three-electrode system using Ag / AgCl as the reference electrode, 1M LiPF6 / PC as the electrolyte, and a Pt wire as the counter electrode. Figure 4 As shown, the exemplary electrochromic polymer has a very low onset oxidation potential of 0.38V (relative to Ag / AgCl). Furthermore, this electrochromic polymer exhibits a yellow color in its colored state with maximum absorbance at 455 nm, and low absorbance in the bleached state within the visible light range (350 nm–800 nm). Figure 5 As shown). The optimal optical contrast at 455nm is as high as 66% (e.g., Figure 6 (As shown).

[0102] Implementation Method 3 - Yellow electrochromic polymer (ECP-Yellow 3) formed by random polymerization

[0103] In one embodiment, the electrochromic polymer (ECP-Yellow 3) has the following formula:

[0104]

[0105] ECP-Yellow 3 was synthesized by preparing a pyrrole derivative-based trimer unit, followed by polymerization of the pyrrole derivative-based trimer unit with ProDOT and EDOT units. The detailed method includes the following steps:

[0106] Step 3-1: Preparation of the diketone derivative product (compound 3)

[0107] Same as step 1-1.

[0108] Step 3-2: Preparation of pyrrole derivative-based trimers (compound 4)

[0109] Same as steps 1-2.

[0110] Step 3-3: Preparation of ECP-Yellow 3

[0111]

[0112] The reaction was the same as in steps 1-3, except that propylene dioxothiophene-2Br (ProDOT-2Br) compound 5 (1.0 eq.), 3,4-ethylene dioxothiophene (EDOT) compound 7 (0.33 eq.), pyrrole derivative-based thiophene trimer compound 4 (0.67 eq.), K2CO3 (2.6 eq.), PivOH (0.3 eq.) and Pd(OAc)2 (0.02 eq.) were added to the Schlenk tube to carry out the reaction.

[0113] Implementation Method 4 - Yellow electrochromic polymer (ECP-Yellow 4) formed by alternating polymerization

[0114] In one embodiment, the electrochromic polymer (ECP-Yellow 4) has the following formula:

[0115]

[0116] ECP-Yellow 4 was synthesized by preparing a pyrrole derivative-based trimer unit, followed by polymerization of the pyrrole derivative-based trimer unit with a ProDOT unit. The detailed method includes the following steps:

[0117] Step 4-1: Preparation of the diketone derivative (compound 9). Compound 9 can be prepared via two different routes.

[0118] Route 4-1A: Compound 9 is prepared by reacting ProDOT with compound 8.

[0119]

[0120] In a Schlenk tube, compound 2 (3.0 g, 3 eq.) of propylene dioxothiophene (ProDOT) was added. The tube was kept under vacuum for about 15 minutes, then purged with N2. This process was repeated three times. Then, 15 mL of anhydrous tetrahydrofuran (THF) was added to the tube using a syringe. The solution was kept at -78°C, and then 2.7 mL of nBuLi solution (2.5 M in hexane) was added. The solution was further heated to room temperature, and then 3,4-dibutoxycyclobut-3-ene-1,2-dione (compound 8, 1 eq.) was added. After reacting for one hour, the reaction was quenched with NH4Cl solution. The resulting solution was extracted with EtOAc to obtain the organic phase. The organic phase was dried, and the solvent was removed under vacuum. The crude product was purified by silica gel chromatography to give the diketone derivative product (compound 9) (yield ~60%-95%).

[0121] Route 4-1B: Preparation of diketone derivative (compound 9) via a 3-step reaction.

[0122] Approach 4-1B - Step 1: Preparation of Compound 12

[0123]

[0124] Dimethyl tartrate (compound 11, 1.0 eq.) was added to a DMF solution. Sodium hydride (2.2 eq.) was then slowly added to the solution. 1-Bromobutane was then added to the solution to initiate the reaction. The organic phase was extracted with DCM and water. The organic phase was collected, and the solvent was removed. The crude product was purified by silica gel chromatography (yield ~50%–85%).

[0125] Pathway 4-1B - Step 2: Preparation of Compound 13

[0126]

[0127] 4.5 eq. of trimethylaluminum chloride (4.6 eq.) was slowly added to a DCM solution of N,O-dimethylhydroxylamine chloride (0 °C). Then, compound 12 (1.0 eq.) was slowly added at 0 °C. The solution was reacted at 0 °C for 1 h, then heated to room temperature and held for 1 h. The reaction was quenched with 1 N HCl solution. The organic phase was extracted from the solution with DCM. The organic phase was collected and the solvent was removed. The crude product was purified by silica gel chromatography (yield ~60%–95%).

[0128] Route 4-1B - Step 3: Preparation of diketone derivative (compound 9)

[0129]

[0130] Compound 2 (2.6 eq.) of propylene dioxothiophene (ProDOT) was added to a Schlenk tube. The tube was kept under vacuum for about 15 minutes, then purged with N2. This process was repeated three times. Then, 15 mL of anhydrous tetrahydrofuran (THF) was added to the tube using a syringe. The solution was kept at -78°C, and then 2.5 mL of nBuLi solution (2.5 M in hexane) was added. Compound 13 was dissolved in 3 mL of dry THF and then added to the Schlenk tube at -78°C. The mixture was heated to room temperature. The reaction was quenched with water, and the organic phase was extracted from the solution with EtOAc. The organic phase was dried, and the solvent was removed under vacuum. The crude product was purified by silica gel chromatography to give the diketone product compound 9 (yield ~60%-90%).

[0131] Step 4-2: Preparation of pyrrole derivative-based trimers (compound 10)

[0132]

[0133] Add diketone compound 9 (500 mg, 1 eq.), 1-hexylamine (137 mg, 3 eq.), propionic acid (10 mg, 0.3 eq.), and 4 mL of anhydrous toluene to a flask. Then heat the mixture to 110 °C under nitrogen and react for 12 hours. Cool the mixture to room temperature and wash with water. Collect the organic phase and remove the solvent using a rotary evaporator. Purify the organic phase by silica gel chromatography to give a pyrrole derivative-based trimer (compound 10) (yield ~60%–90%).

[0134] Step 4-3: Preparation of ECP-Yellow 4

[0135]

[0136] The reaction was the same as in steps 1-3, except that propylene dioxothiophene-2Br (ProDOT-2Br) compound 5 (1.0 eq.), pyrrole derivative-based trimer compound 10 (1.0 eq.), K2CO3 (2.6 eq.), PivOH (0.3 eq.) and Pd(OAc)2 (0.02 eq.) were added to the Schlenk tube to carry out the reaction.

[0137] Implementation Method 5 - Yellow electrochromic polymer (ECP-Yellow 5) formed by alternating polymerization

[0138] In one embodiment, the electrochromic polymer (ECP-Yellow 5) has the following formula:

[0139]

[0140] ECP-Yellow 5 was synthesized by preparing a pyrrole derivative-based trimer unit, followed by polymerization of the pyrrole derivative-based trimer unit with a ProDOT unit. The detailed method includes the following steps:

[0141] Step 5-1: Preparation of the diketone derivative product (compound 14).

[0142]

[0143] Same as step 1-1, except that compound 2 was replaced with 3,4-ethylenedioxythiophene (EDOT) (1.81 g, 2.6 eq.) and added to the Schlenk tube.

[0144] Step 5-2: Preparation of a pyrrole derivative-based trimer (compound 15)

[0145]

[0146] Add diketone compound 14 (1.0 g, 1 eq.), 2-ethylhexylamine (529 mg, 3 eq.), and 4 mL of hexafluoro-2-propanol to a flask. Heat the mixture to 70 °C under nitrogen and react for 12 hours. Cool the mixture to room temperature and add 20 mL of LDM, then wash with water. Collect the organic phase and remove the solvent using a rotary evaporator. Purify the crude product by silica gel chromatography to give a pyrrole derivative-based trimer (compound 15) (yield ~60%–90%).

[0147] Step 5-3: Prepare ECP-yellow 5.

[0148]

[0149] The reaction was carried out in the same manner as steps 1-3, except that propylene dioxothiophene-2Br (ProDOT-2Br) (compound 16, 1.0 eq.), a pyrrole derivative-based trimer (compound 15, 1.0 eq.), K2CO3 (2.6 eq.), PivOH (0.3 eq.) and Pd(OAc)2 (0.02 eq.) were added to the Schlenk tube to carry out the reaction.

[0150] Implementation Method 6 - Yellow electrochromic polymer (ECP-Yellow 6) formed by alternating polymerization

[0151] In one embodiment, the electrochromic polymer (ECP-Yellow 6) has the following formula:

[0152]

[0153] ECP-Yellow 6 was synthesized by preparing a pyrrole derivative-based trimer unit, followed by polymerization of the pyrrole derivative-based trimer unit with a ProDOT unit. The detailed method includes the following steps:

[0154] Step 6-1: Preparation of diketone derivative (compound 18)

[0155]

[0156] Same as step 1-1, except that compound 17 (AcDOT) (2.91 g, 2.6 eq.) replaces compound 2 and is added to a Schlenk tube for the reaction.

[0157] Step 6-2: Preparation of a pyrrole derivative-based trimer (compound 19)

[0158]

[0159] To a flask, add diketone compound 18 (1.0 g, 1 eq.), 1-hexylamine (563 mg, 3 eq.), propionic acid (41 mg, 0.3 eq.), and 4 mL of anhydrous toluene. The mixture is then heated to 110 °C under nitrogen and reacted for 12 hours. The mixture is cooled to room temperature, then 20 mL of DCM is added and the mixture is washed with water. The organic phase is collected and the solvent is removed using a rotary evaporator. The organic phase is purified by silica gel chromatography to give pyrrole derivative-based trimer compound 19 (yield ~60%–90%).

[0160] Step 6-3: Prepare ECP-Yellow 6.

[0161]

[0162] The reaction was the same as in steps 1-3, except that propylene dioxothiophene-2Br (ProDOT-2Br) compound 5 (1.0 eq.), pyrrole derivative-based trimer compound 19 (1.0 eq.), K2CO3 (2.6 eq.), PivOH (0.3 eq.) and Pd(OAc)2 (0.02 eq.) were added to the Schlenk tube to carry out the reaction.

[0163] Implementation Method 7 - Yellow electrochromic polymer (ECP-Yellow 7) formed by random polymerization

[0164] In one embodiment, the electrochromic polymer (ECP-Yellow 7) has the following formula:

[0165]

[0166] ECP-Yellow 7 was synthesized by preparing a pyrrole derivative-based trimer unit, followed by polymerization of the pyrrole derivative-based trimer unit with a ProDOT unit. The detailed method includes the following steps:

[0167] Step 7-1: Preparation of diketone derivative (compound 3)

[0168] Same as step 1-1.

[0169] Step 7-2: Preparation of pyrrole derivative-based trimers (compound 4)

[0170] Same as steps 1-2.

[0171] Step 7-3: Preparation of ECP-Yellow 7 via two different routes

[0172] Pathway 7-3A: Preparation of ECP-Yellow 7

[0173]

[0174] A pyrrole derivative-based trimer compound 4 (1 g, 1.0 eq.) and a propylene dioxothiophene (ProDOT) monomer compound 2 (0.428 g, 1.0 eq.) were dissolved in 20 mL of chloroform at 0 °C. 1.58 g of FeCl3 (10 eq.) was dissolved in 8 mL of nitromethane and then added dropwise to the chloroform solution with stirring. After reacting at room temperature for 15 hours, the mixture was added dropwise to 100 mL of methanol to precipitate the resulting polymer. The solid was filtered and washed with 1 N HCl and methanol. The solid was then placed in 40 mL of chloroform and reduced with hydrazine. After washing the chloroform solution three times with water, the organic solution was transferred to methanol to precipitate the polymer product. The product was filtered and dried to give ECP-Yellow 7.

[0175] Route 7-3B: Preparation of ECP-Yellow 7

[0176]

[0177] Add pyrrole monomer compound 4 (1 g, 1.0 eq.), propylene dioxothiophene (ProDOT) compound 2 (1.0 eq.), K₂CO₃ (3.0 eq.), PivOH (1.0 eq.), Pd(OAc)₂ (0.05 eq.), and Ag₂CO₃ (3.0 eq.) to a Schlenk tube. Add 10 mL of dimethylacetamide (DMAc) to the tube and heat the mixture at 120 °C for 12 hours. Transfer the heated reaction mixture to a 1:1 mixture of CH₃OH and 1M HCl with stirring. Filter the mixture to obtain a solid. Dissolve the solid in chloroform to form a solution, then filter the solution and wash with 1M HCl. Concentrate the organic phase and precipitate with CH₃OH. Filter and dry the organic phase to give yellow polymer 7. Yield: approximately 80%–100%.

[0178] Implementation Method 8 - Red electrochromic polymer (ECP-Red 1) formed by random polymerization

[0179] In one embodiment, the electrochromic polymer (ECP-Red 1) has the following formula:

[0180]

[0181] ECP-Red 1 was synthesized by preparing a pyrrole derivative-based trimer unit, followed by polymerization of the pyrrole derivative-based trimer unit with EDOT and ProDOT units. The detailed method includes the following steps:

[0182] Step 8-1: Preparation of diketone derivative (compound 3)

[0183] Same as step 1-1.

[0184] Step 8-2: Preparation of pyrrole derivative-based trimers (compound 4)

[0185] Same as steps 1-2.

[0186] Step 8-3: Preparation of ECP-Red 1

[0187]

[0188] Similar to steps 1-3, except that pyrrole-based trimer compound 4 (0.35 eq.), ethylenedioxythiophene (EDOT) compound 7 (0.65 eq.), propylenedioxythiophene (ProDOT) monomer compound 20 (1 eq.), K2CO3 (2.6 eq.), PivOH (0.3 eq.) and Pd(OAc)2 (0.02 eq.) were added to the Schulenke test tube to carry out the reaction.

[0189] The obtained ECP-Red 1 was dissolved in chloroform at a concentration of 20 mg / ml. The ECP-Red 1 chloroform solution was spin-coated onto an ITO-coated glass substrate. The performance of the obtained ECP-Red 1 film was tested in a three-electrode system using Ag / AgCl as the reference electrode, 0.2 M LiPTFSi / PC as the electrolyte, and a Pt wire as the counter electrode. Figure 7 As shown, the exemplary electrochromic polymer has a very low onset oxidation potential of approximately 0.3 V (relative to Ag / AgCl). Furthermore, the electrochromic polymer exhibits a red color in its colored state with maximum absorbance at 524 nm, and low absorbance in the bleached state within the visible light range (400 nm–800 nm). Figure 9 As shown). The corresponding images of the ECP-Red 1 film in the colored and faded states are shown in Figure 8(A) and Figure 8(B). The optimal optical contrast at 550 nm is as high as 61% (e.g., ...). Figure 10 (As shown).

Claims

1. An electrochromic polymer, characterized in that, Includes the following formula ， in, Tr is a trimer based on pyrrole or pyrrole derivatives, which has the following formula: ， Ar1 is , Ar2 is , Ar3 is , n is an integer greater than 0; a is an integer greater than 0; b, c, and d are integers not less than 0, and the ratio of a to the sum of b, c, and d is between 0.1 and 4; Among them, R3-R5 and R8-R 13 Each is independently selected from: hydrogen, C1-C 30 Alkyl, C2-C 30 alkenyl, C2-C 30 alkynyl group, C2-C 30 Alkyl carbonyl, C1-C 30 Alkoxy, C3-C 30 Alkoxyalkyl, C2-C 30 alkoxycarbonyl, C4-C 30 alkoxycarbonylalkyl, C1-C 30 Alkyl thio, C1-C 30 amino carbonyl, C4-C 30 aminoalkyl, C1-C 30 Alkylamino, C1-C 30 Alkyl sulfonyl, C3-C 30 alkylsulfonylalkyl, C6-C 18 Aryl, C3-C 15 cycloalkyl, C3-C 30 Cycloalkylamino, C5-C 30 Cycloalkylalkylamino, C5-C 30 cycloalkylalkyl, C5-C 30 Cycloalkylalkoxy, C1-C 12 Heterocyclic groups, C1-C 12 Heterocyclic radicals, C3-C 30 Heterocyclic alkoxy, C1-C 30 Heterocyclic alkoxy, C1-C 30 Heterocyclic amino groups, C5-C 30 Heterocyclic alkylamino, C2-C 12 Heterocyclic carbonyl, C3-C 30 Heterocyclic alkyl, C1-C 13 heteroaryl and C3-C 30 Heteroarylalkyl; and R1, R2, R6, and R7 are each independently selected from: C1-C 30 Alkyl, C2-C 30 alkenyl, C2-C 30 alkynyl group, C2-C 30 Alkyl carbonyl, C1-C 30 Alkoxy, C3-C 30 Alkoxyalkyl, C2-C 30 alkoxycarbonyl, C4-C 30 alkoxycarbonylalkyl, C1-C 30 Alkyl thio, C1-C 30 amino carbonyl, C4-C 30 aminoalkyl, C1-C 30 Alkylamino, C1-C 30 Alkyl sulfonyl, C3-C 30 alkylsulfonylalkyl, C6-C 18 Aryl, C3-C 15 cycloalkyl, C3-C 30 Cycloalkylamino, C5-C 30 Cycloalkylalkylamino, C5-C 30 cycloalkylalkyl, C5-C 30 Cycloalkylalkoxy, C1-C 12 Heterocyclic groups, C1-C 12 Heterocyclic radicals, C3-C 30 Heterocyclic alkoxy, C1-C 30 Heterocyclic alkoxy, C1-C 30 Heterocyclic amino groups, C5-C 30 Heterocyclic alkylamino, C2-C 12 Heterocyclic carbonyl, C3-C 30 Heterocyclic alkyl, C1-C 13 heteroaryl and C3-C 30 Heteroarylalkyl.

2. The electrochromic polymer according to claim 1, characterized in that, The electrochromic polymer has an initial oxidation potential of less than 0.6 V with Ag / AgCl as the reference electrode.

3. The electrochromic polymer of claim 1, wherein, The electrochromic polymer has an optical contrast of over 50% at its maximum absorption wavelength.

4. The electrochromic polymer of claim 1, wherein, The maximum absorption wavelength of the electrochromic polymer is 400 nm to 550 nm.

5. The electrochromic polymer of claim 1, wherein, Tr is selected from one of the following formulas: , or , or ; Ar1, Ar2, and Ar3 are each independently selected from one of the following formulas: , or , or ; X is S or O; R 51 -R 59 Each is independently selected from: hydrogen, C1-C 30 Alkyl, C2-C 30 alkenyl, C2-C 30 alkynyl group, C2-C 30 Alkyl carbonyl, C1-C 30 Alkoxy, C3-C 30 Alkoxyalkyl, C2-C 30 alkoxycarbonyl, C4-C 30 alkoxycarbonylalkyl, C1-C 30 Alkyl thio, C1-C 30 amino carbonyl, C4-C 30 aminoalkyl, C1-C 30 Alkylamino, C1-C 30 Alkyl sulfonyl, C3-C 30 alkylsulfonylalkyl, C6-C 18 Aryl, C3-C 15 cycloalkyl, C3-C 30 Cycloalkylamino, C5-C 30 Cycloalkylalkylamino, C5-C 30 cycloalkylalkyl, C5-C 30 Cycloalkylalkoxy, C1-C 12 Heterocyclic groups, C1-C 12 Heterocyclic radicals, C3-C 30 Heterocyclic alkoxy, C1-C 30 Heterocyclic alkoxy, C1-C 30 Heterocyclic amino groups, C5-C 30 Heterocyclic alkylamino, C2-C 12 Heterocyclic carbonyl, C3-C 30 Heterocyclic alkyl, C1-C 13 heteroaryl and C3-C 30 Heteroarylalkyl.

6. The electrochromic polymer according to claim 5, characterized in that, X is O.

7. The electrochromic polymer of claim 1, wherein, The electrochromic polymer has the following formula: 、 or , or , or , or , or , or , or .

8. A method for forming the electrochromic polymer of claim 1, characterized in that, The method includes: preparing a thiophene trimer unit based on pyrrole or a pyrrole derivative; and preparing the electrochromic polymer by polymerizing the thiophene trimer unit based on pyrrole or a pyrrole derivative with a thiophene unit.

9. The method of claim 8, wherein, The method further includes contacting the diketone derivative with a primary amine in the presence of hexafluoro-2-propanol to form the pyrrole or pyrrole derivative.

10. The method of claim 9, wherein, The method further includes contacting a lithium-ionized thiophene derivative with N1,N4-dimethoxy-N1,N4-dimethylbutanediamide to form the diketone derivative.

11. An apparatus comprising the electrochromic polymer according to any one of claims 1-7.

Images