KR20180080441A - Non-amphiphilic polymer film and preparing method of the same - Google Patents

Abstract

The present invention relates to a non-amphiphilic polymer film and a preparing method of the same. The preparing method of the non-amphiphilic polymer film comprises the following steps: dropping a non-amphiphilic polymer containing solution onto a subphase liquid surface; and forming the non-amphiphilic polymer film as the non-amphiphilic polymer containing solution evaporates on the interface of the subphase liquid-air interface. The non-amphiphilic polymer film according to an embodiment of the present invention exhibits higher hole mobility and conductivity than conventional spin-cast films and other P3HT nanowire-based films because the polymer film has no insulating blocks.

Description

TECHNICAL FIELD [0001] The present invention relates to a non-ampholytic polymer membrane and a method for producing the same,

The present invention relates to an amorphous polymer film, and a process for producing the amorphous polymer film.

BACKGROUND OF THE INVENTION Conjugated polymers have been extensively studied for their optical and electrical properties and their applications in optoelectronic devices such as field effect transistors (FETs), organic light emitting diodes, and solar cells. An important challenge in fabricating high performance conjugated polymer devices is that the optical and transport properties of conjugated polymers are highly dependent on their packing structure and nanoscale morphology. Conjugated polymer membranes prepared by conventional techniques such as spin-coating generally consist of nanoscale crystalline domains and contain grain boundaries that serve as charge trapping sites. Thus, there have been many studies to improve the thin film morphology of conjugated polymers by adopting processes such as solvent and thermal annealing.

In recent years, researchers have explored a novel approach to controlling polymer morphology based on solution-phase self-assembly. For example, Ito et al. First dissolve poly (3-alkylthiophene, P3AT) in a marginal solvent such as anisole at high temperature and then crystallize the polymer In another group, the conjugated block copolymers were synthesized and assembled into well-aligned nanofibers. The main motivation for this effort was controlled The nanoscale polymeric building blocks can be prepared in a two- or three-dimensional (3D) manner by preparing nanoscale assemblies of conjugated polymers having a packing structure and using them as building blocks for producing well-ordered hierarchical assembly of conjugated polymers. It is a difficult task to form an extended array, and thus the two-step hierarchical self-assembly approach has achieved limited success so far.

Korean Patent Publication No. 2011-0046111 discloses a method for controlling the self-assembled structure of a poly (3-hexylthiophene) based block copolymer.

The present invention provides an amorphous polymer film and a method for producing the amorphous polymer film.

However, the problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

A first aspect of the invention is directed to a process for preparing a polymeric material, comprising: dropping an amorphous polymer-containing solution onto a subphase liquid surface; And forming the non-ampholytic polymer film by evaporating the solvent of the non-ampholytic polymer-containing solution at the sub-phase liquid-air interface.

A second aspect of the present invention provides an amorphous polymeric membrane produced according to the method according to the first aspect of the present application.

According to one embodiment of the present disclosure there is provided a process for the preparation of a single solution comprising a tightly packed nanowire array by slow evaporation of a solvent of poly (3-hexylthiophene), P3HT] at the sub- An amorphous P3HT film which is a polymer can be obtained.

The non-amorphous polymer film according to one embodiment of the present invention exhibits higher hole mobility and conductivity than conventional spin-cast films and other P3HT nanowire-based films due to the absence of an insulating block, Lt; RTI ID = 0.0 > solid substrate. ≪ / RTI >

The non-amorphous polymer membrane according to one embodiment of the present invention has an advantage that it is easier to synthesize and purify than a polymer membrane using a conventional block copolymer.

According to one embodiment of the present application, by utilizing various sub-phase liquids at the sub-phase liquid-air interface, unlike conventional sub-phase liquid-air interface self-assembly confined to ampholytic polymers, P3HT can be used to manufacture a large area self-assembled ultra thin film at the sub-phase liquid-interface.

1 is a synthesis diagram of poly (3-hexylthiophene, P3HT) in one embodiment of the present invention.
Figure 2 is a graph showing a representative ¹ H NMR spectrum of P3HT in one embodiment of the present invention.
Figure 3 is a GPC chromatogram (SPD trace, 450 nm) of P3HT in one embodiment of the invention.
4 is a schematic view of an air-liquid interfacial self-assembly (ALISA) of a P3HT film, in one embodiment of the present invention.
5A-5E illustrate a low magnification TEM image (a) of a P3HT film, a high magnification TEM image (b) representing an aligned nanowire array, an FFT image of FIG. (c), a color-delimited TEM image (d) representing the different domains of the nanowire array constructed by the image J software, and a structural model (e) of the P3HT nanowire.
Figures 6 (a) - (d) are graphs showing TEM images of P3HT membranes self-assembled in varying concentrations of toluene in an embodiment of the present invention at 30 [mu] M (a), 50 [ (c), and 80 [mu] M (d) (200 [mu] L).
7A to 7C are TEM images of a P3HT film prepared using a low molecular weight and high molecular weight P3HT, respectively, in one embodiment of the present invention, each of (a) a short length (Mw = 3.4 kDa) , (b) middle length (Mw = 5.1 kDa), and (c) longest length (Mw = 50 kDa).
Figures 8 (a) - (c) illustrate, in an embodiment of the present invention, a TEM image of a P3HT film made using sub-phase liquids of different polarity, comprising DEG (a), TGEE Shows the assembled P3HT polymer structure in glycerol (c).
9A and 9B are graphs showing the UV-vis spectrum (a) and the calculated extinction coefficient value (b) of pure and oxidized P3HT in one embodiment of the present invention, wherein the extinction coefficient The values were calculated to be 2.51 × 10 ⁵ and 1.81 × 10 ⁵ , respectively, using Beer's law.
Figures 9 (c) and 9 (d) are TEM images of self-assembled ALISA P3HT membranes using freshly prepared P3HT (c) and degraded P3HT polymer (d), in one embodiment of the invention.
10 (a) to 10 (c) are graphs showing FET characteristics of a P3HT film in one embodiment of the present invention, which are schematic views (a) showing a film transistor structure, a nanowire film and a spin- (B) the current density versus source-drain bias voltage (b) with different gate voltage conditions for the device, and the gate effect (c) for the device based on the nanowire film and the spin-cast bulk film.
Figures 11 (a) and 11 (b) show, in an embodiment of the invention, the solvent annealing effect on the ALISA film of P3HT ₃₀ , each of which comprises nanowire (a) assembled without solvent vapor, (B) nanowires assembled with solvent vapor.
11 (c) and 11 (d) show orientation color maps of the above (a) and (b), respectively, in one embodiment of the present invention.
Figs. 11 (e) and 11 (f) show statistical data according to the hues shown in Figs. 11 (c) and 11 (d) in the embodiment of the present application.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. It should be understood, however, that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In the drawings, the same reference numbers are used throughout the specification to refer to the same or like parts.

Throughout this specification, when a part is referred to as being "connected" to another part, it is not limited to a case where it is "directly connected" but also includes the case where it is "electrically connected" do.

Throughout this specification, when a member is " on " another member, it includes not only when the member is in contact with the other member, but also when there is another member between the two members.

Throughout this specification, when an element is referred to as " including " an element, it is understood that the element may include other elements as well, without departing from the other elements unless specifically stated otherwise. The terms " about ", " substantially ", etc. used to the extent that they are used throughout the specification are intended to be taken to mean the approximation of the manufacturing and material tolerances inherent in the stated sense, Accurate or absolute numbers are used to help prevent unauthorized exploitation by unauthorized intruders of the referenced disclosure.

The word " step (or step) " or " step " used to the extent that it is used throughout the specification does not mean " step for.

Throughout this specification, the term " combination (s) thereof " included in the expression of the machine form means a mixture or combination of one or more elements selected from the group consisting of the constituents described in the expression of the form of a marker, Quot; means at least one selected from the group consisting of the above-mentioned elements.

Throughout this specification, the description of "A and / or B" means "A or B, or A and B".

Throughout this specification, the substrate of a "film" may be one comprising a film, a thin film, an ultrathin film, a film, and combinations thereof.

Throughout the present specification, the phrase "subphase" or "subphase" means a liquid used when a membrane or layer is to be formed at the liquid-air interface, A film or a layer is formed at the interface. Formation of a film or a layer is accomplished by adding a sub-phase liquid, spreading a solution containing the substance to be formed on the sub-phase liquid, or by self-assembling as the solvent of the solution evaporates A desired film or layer is formed. The sub-phase liquid may be different in kind depending on the kind, thickness, or area of the film or layer to be formed, and the sub-phase liquid may be mixed with the solution containing the substance to be formed Lt; / RTI >

Hereinafter, embodiments and examples of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to these embodiments and examples and drawings.

A first aspect of the invention is directed to a process for preparing a polymeric material, comprising: dropping an amorphous polymer-containing solution onto a subphase liquid surface; And forming the non-ampholytic polymer film by evaporating the solvent of the non-ampholytic polymer-containing solution at the sub-phase liquid-air interface.

In one embodiment of the present invention, the non-ampholytic polymer film may be formed as the non-ampholytic polymer is self-assembled at the sub-phase liquid-air interface. For example, as the solvent of the non-ampholytic polymer-containing solution slowly evaporates at the sub-phase liquid-air interface, a large-sized non-ampholytic polymer film may be formed on the surface of the sub-phase liquid.

In one embodiment of the present invention, the subphase liquid can be used without limitation as long as it is not mixed with the non-ampholytic polymer-containing solution, and examples thereof include water, diethylene glycol, triethylene monoethyl ether, glycerol, But are not limited to, materials selected from the group consisting of combinations thereof, and combinations thereof.

In one embodiment of the present invention, the solvent of the non-ampholytic polymer-containing solution may be different depending on the type of the non-ampholytic polymer to be used, for example, toluene, chloroform, dichloromethane, But are not limited to, those selected from the group consisting of < RTI ID = 0.0 >

In one embodiment of the present invention, the non-ampholytic polymer membrane may comprise an array of nanowires of the non-ampholytic polymer. For example, as the solvent of the non-ampholytic polymer-containing solution evaporates at the sub-phase liquid-air interface, the non-ampholytic polymer strands are packed with one-dimensional wires and the polymer nanowires Self assembled to form an amorphous polymeric film comprising an array of well-aligned nanowires.

In one embodiment of the present invention, the width of the nanowire of the amorphous polymer film may be about 7 nm to about 16 nm, but may not be limited thereto. For example, the width of the nanowires of the non-ampholytic polymer membrane may be from about 7 nm to about 16 nm, from about 7 nm to about 14 nm, from about 7 nm to about 12 nm, from about 7 nm to about 10 nm, From about 10 nm to about 14 nm, from about 10 nm to about 12 nm, from about 12 nm to about 16 nm, from about 12 nm to about 14 nm, or from about 14 nm to about 16 nm, But may not be limited.

In one embodiment of the present invention, the non-ampholytic polymer may comprise a homopolymer.

In one embodiment of the present invention, the non-amorphous polymer may be a polythiophene series or a poly (p-phenylene vinylene) (PPV) series.

In one embodiment herein, the polythiophene series is a poly (N-9'-heptadecanyl-2,7-carbazole-alt-5,5- (4 ', 7'-di- 2 ', 1', 3'-benzothiadiazole)]}, PCPDTBT {poly [2,6- (4,4-bis- (2-ethylhexyl) -4H-cyclopenta [ (3-alkylthiophene), and combinations thereof, but is not limited thereto. The term " polythiophene " .

For example, the poly (3-alkylthiophene) may be selected from the group consisting of poly (3-hexylthiophene), poly (3-butylthiophene), poly (3-octylthiophene) And combinations thereof. The polyparaphenylenevinylene series may be selected from the group consisting of poly [2-methoxy-5- (2-ethylhexyloxy) -1,4-phenylenevinylene] }, MDMO-PPV {Poly [2- (2 ', 5' '- bis (2', 3 ', 5'-dimethyloctyloxy) -1,4-phenylenevinylene]}, BEHP- (2-ethylhexyloxy) phenyl) -1,4-phenylene vinylene]}, and combinations thereof.

Conventionally, it is difficult to form a polymer film through self-assembly at a sub-phase liquid-interface with a homopolymer alone. Thus, an interfacial-magnetic assembly is formed using a block copolymer of P3HT and another polymer. According to one embodiment of the present invention, Forming a large-area, non-ampholytic polymeric membrane, including an array of nanowires aligned through self-assembly at the sub-phase liquid-air interface with only the non-ampholytic homopolymer due to the concentration and molecular weight of the polymer, can do.

In one embodiment of the present invention, nanowire array formation of the non-ampholytic polymer film formed may vary depending on the viscosity of the sub-phase liquid, but may not be limited thereto. For example, if the viscosity of the subphase liquid exceeds about 35 mPa.s, the nanowire array may not be formed in the non-ampholytic polymer film, but may not be limited thereto.

In one embodiment, the concentration of the non-ampholytic polymer-containing solution depends on the size of the monolayer to be formed and the thickness of the finally formed film, for example, a diameter of about 5 cm and a diameter of about 20 cm ^But may be, but not limited to, about 10 [mu] M to about 100 [mu] M, based on monolayer formation having a size of ² . For example, if the concentration of the non-ampholytic polymer-containing solution exceeds about 1.5 times the concentration at which a monolayer polymer membrane having a diameter of about 5 cm in diameter and a size of about 20 cm ² is formed, ) -Type polymer membrane may be formed. When the concentration of the non-ampholytic polymer-containing solution is less than the concentration at which a monolayer polymer membrane having a diameter of about 5 cm and a size of about 20 cm ² is formed, , The concentration of the non-ampholytic polymer-containing solution is preferably about 10 μM to about 100 μM when a monolayer is to be formed.

In one embodiment of the invention, the non-amphoteric polymer concentration of the phosphorus-containing solution is if, based on the mono-layer is formed having a diameter and a size of about 20 cm ² of about 5 cm in size, from about 10 μM to about 100 μM About 10 μM to about 80 μM, about 10 μM to about 60 μM, about 10 μM to about 40 μM, about 10 μM to about 20 μM, about 20 μM to about 100 μM, about 20 μM to about 80 μM, about About 40 [mu] M to about 60 [mu] M, about 60 [mu] M to about 100 [mu] M, about 60 [mu] M to about 60 [ To about 80 M, from about 80 M to about 100 M, from about 10 M to about 50 M, or from about 50 M to about 100 M, for example.

In one embodiment of the invention, the molecular weight of the non-ampholytic polymer may be from about 1 kDa to about 10 kDa.

In one embodiment of the present invention, when the molecular weight of the non-ampholytic polymer is more than about 10 kDa, the crystallinity increases and the interactions between each other become strong, and the folding of the chains occurs, The width of the nanowires of the ampholytic polymer membrane may be narrower than the contour length of the non-ampholytic polymer, thereby forming a polymer film of an entangled form. Therefore, a long and dense nanowire packing structure is included The molecular weight of the non-ampholytic polymer for forming the non-ampholytic polymer is preferably from about 1 kDa to about 10 kDa. For example, the molecular weight of the non-ampholytic polymer can range from about 1 kDa to about 10 kDa, from about 1 kDa to about 8 kDa, from about 1 kDa to about 6 kDa, from about 1 kDa to about 4 kDa, from about 2 kDa to about 10 kDa, from about 2 kDa to about 8 kDa, from about 2 kDa to about 6 kDa, from about 2 kDa to about 4 kDa, from about 4 kDa to about 10 kDa, from about 4 kDa to about 8 kDa, But is not limited to, from about 4 kDa to about 6 kDa, from about 6 kDa to about 10 kDa, from about 6 kDa to about 8 kDa, from about 8 kDa to about 10 kDa, or from about 1.5 kDa to about 3.5 kDa .

In one embodiment of the present invention, the degree of formation of the nanowires of the ampholytic polymer membrane may vary depending on oxidation of the non-ampholytic polymer by light or air, but the present invention is not limited thereto. For example, if the non-ampholytic polymer is oxidized by light or air, photooxidation may occur, and a defect formed in the skeleton of the non-ampholytic polymer by the generated photo-oxidation may cause the nanowire of the non- But may not be limited thereto.

A second aspect of the present invention provides an amorphous polymeric membrane produced according to the method according to the first aspect of the present application. The detailed description of the non-ampholytic polymer membrane according to the second aspect of the present application will be omitted from the description of the first aspect of the present application. However, the description of the first aspect of the present application is not intended to limit the scope of the present invention The same can be applied to the two sides.

In one embodiment of the present invention, the non-ampholytic polymer film is formed by dropping an amorphous polymer-containing solution onto a sub-phase liquid surface; And a solvent of the non-ampholytic polymer-containing solution is evaporated as the non-ampholytic polymer is self-assembled at the sub-phase liquid-air interface. For example, as the solvent of the non-ampholytic polymer-containing solution slowly evaporates at the sub-phase liquid-air interface, a large-sized non-ampholytic polymer film may be formed on the surface of the sub-phase liquid.

In one embodiment of the present invention, the thickness of the non-ampholytic polymer film may be about 1 nm to about 20 nm, but may not be limited thereto. For example, the thickness of the non-ampholytic polymer film may be from about 1 nm to about 20 nm, from about 1 nm to about 16 nm, from about 1 nm to about 12 nm, from about 1 nm to about 8 nm, from about 4 nm to about 20 nm, from about 4 nm to about 20 nm, from about 4 nm to about 16 nm, from about 4 nm to about 12 nm, from about 4 nm to about 8 nm, from about 8 nm to about 20 nm, From about 8 nm to about 12 nm, from about 12 nm to about 20 nm, from about 12 nm to about 16 nm, or from about 16 nm to about 20 nm.

In one embodiment of the present invention, the subphase liquid can be used without limitation as long as it is not mixed with the non-ampholytic polymer-containing solution, and examples thereof include water, diethylene glycol, triethylene monoethyl ether, glycerol, But are not limited to, materials selected from the group consisting of combinations thereof, and combinations thereof.

In one embodiment of the invention, the subphase liquid may be added at different concentrations or volumes depending on the type of the non-ampholytic polymer used, the area or thickness of the polymer membrane to be obtained, or the size of the vessel in which the reaction is conducted .

In one embodiment of the present invention, the solvent of the non-ampholytic polymer-containing solution may be different depending on the type of the non-ampholytic polymer to be used, for example, toluene, chloroform, dichloromethane, But are not limited to, those selected from the group consisting of < RTI ID = 0.0 >

In one embodiment of the present invention, the non-ampholytic polymer membrane may comprise an array of nanowires of the non-ampholytic polymer. For example, as the solvent of the non-ampholytic polymer-containing solution evaporates at the sub-phase liquid-air interface, the non-ampholytic polymer strands are packed with one-dimensional wires and the polymer nanowires Self assembled to form an amorphous polymeric film comprising an array of well-aligned nanowires.

In one embodiment of the present invention, the width of the nanowire of the amorphous polymer film may be about 7 nm to about 16 nm, but may not be limited thereto. For example, the width of the nanowires of the non-ampholytic polymer membrane may be from about 7 nm to about 16 nm, from about 7 nm to about 14 nm, from about 7 nm to about 12 nm, from about 7 nm to about 10 nm, From about 10 nm to about 14 nm, from about 10 nm to about 12 nm, from about 12 nm to about 16 nm, from about 12 nm to about 14 nm, or from about 14 nm to about 16 nm, But may not be limited.

In one embodiment of the present invention, the non-ampholytic polymer may comprise a homopolymer.

In one embodiment of the present invention, the non-amorphous polymer may be a polythiophene series or a poly (p-phenylene vinylene) (PPV) series.

In one embodiment herein, the polythiophene series is a poly (N-9'-heptadecanyl-2,7-carbazole-alt-5,5- (4 ', 7'-di- 2 ', 1', 3'-benzothiadiazole)]}, PCPDTBT {poly [2,6- (4,4-bis- (2-ethylhexyl) -4H-cyclopenta [ (3-alkylthiophene), and combinations thereof, but is not limited thereto. The term " polythiophene " .

For example, the poly (3-alkylthiophene) may be selected from the group consisting of poly (3-hexylthiophene), poly (3-butylthiophene), poly (3-octylthiophene) And combinations thereof. The polyparaphenylenevinylene series may be selected from the group consisting of poly [2-methoxy-5- (2-ethylhexyloxy) -1,4-phenylenevinylene] }, MDMO-PPV {Poly [2- (2 ', 5' '- bis (2', 3 ', 5'-dimethyloctyloxy) -1,4-phenylenevinylene]}, BEHP- (2-ethylhexyloxy) phenyl) -1,4-phenylene vinylene]}, and combinations thereof.

Conventionally, it is difficult to form a polymer film through self-assembly at a sub-phase liquid-interface with a homopolymer alone. Thus, an interfacial-magnetic assembly is formed using a block copolymer of P3HT and another polymer. According to one embodiment of the present invention, Forming a large-area, non-ampholytic polymeric membrane, including an array of nanowires aligned through self-assembly at the sub-phase liquid-air interface with only the non-ampholytic homopolymer due to the concentration and molecular weight of the polymer, can do.

In one embodiment of the present invention, nanowire array formation of the non-ampholytic polymer film formed may vary depending on the viscosity of the sub-phase liquid, but may not be limited thereto. For example, if the viscosity of the subphase liquid exceeds about 35 mPa.s, the nanowire array may not be formed in the non-ampholytic polymer film, but may not be limited thereto.

In one embodiment, the concentration of the non-ampholytic polymer-containing solution depends on the size of the monolayer to be formed and the thickness of the finally formed film, for example, a diameter of about 5 cm and a diameter of about 20 cm ^But may be, but not limited to, about 10 [mu] M to about 100 [mu] M, based on monolayer formation having a size of about 2 [mu] M. For example, if the concentration of the non-ampholytic polymer-containing solution exceeds about 1.5 times the concentration at which the monolayer polymer film is formed, a polymer film of an entangled form may be formed, -Containing solution is less than the concentration at which the monolayer polymer membrane is formed, it is possible to form sparsely aligned short nanowires. Therefore, when the monolayer is formed, the concentration of the non-ampholytic polymer-containing solution Is about 10 [mu] M to about 100 [mu] M.

In one embodiment of the invention, the non-amphoteric polymer concentration of the phosphorus-containing solution is if, based on the mono-layer is formed having a diameter and a size of about 20 cm ² of about 5 cm in size, from about 10 μM to about 100 μM About 10 μM to about 80 μM, about 10 μM to about 60 μM, about 10 μM to about 40 μM, about 10 μM to about 20 μM, about 20 μM to about 100 μM, about 20 μM to about 80 μM, about About 40 [mu] M to about 60 [mu] M, about 60 [mu] M to about 100 [mu] M, about 60 [mu] M to about 60 [ To about 80 M, from about 80 M to about 100 M, from about 10 M to about 50 M, or from about 50 M to about 100 M, for example.

In one embodiment of the invention, the molecular weight of the non-ampholytic polymer may be from about 1 kDa to about 10 kDa.

In one embodiment of the present invention, when the molecular weight of the non-ampholytic polymer is more than about 10 kDa, the crystallinity increases and the interactions between each other become strong, and the folding of the chains occurs, The width of the nanowires of the ampholytic polymer membrane may be narrower than the contour length of the non-ampholytic polymer, thereby forming a polymer film of an entangled form. Therefore, a long and dense nanowire packing structure is included The molecular weight of the non-ampholytic polymer for forming the non-ampholytic polymer is preferably from about 1 kDa to about 10 kDa. For example, the molecular weight of the non-ampholytic polymer can range from about 1 kDa to about 10 kDa, from about 1 kDa to about 8 kDa, from about 1 kDa to about 6 kDa, from about 1 kDa to about 4 kDa, from about 2 kDa to about 10 kDa, from about 2 kDa to about 8 kDa, from about 2 kDa to about 6 kDa, from about 2 kDa to about 4 kDa, from about 4 kDa to about 10 kDa, from about 4 kDa to about 8 kDa, But is not limited to, from about 4 kDa to about 6 kDa, from about 6 kDa to about 10 kDa, from about 6 kDa to about 8 kDa, from about 8 kDa to about 10 kDa, or from about 1.5 kDa to about 3.5 kDa .

In one embodiment of the present invention, the degree of formation of the nanowires of the ampholytic polymer membrane may vary depending on oxidation of the non-ampholytic polymer by light or air, but the present invention is not limited thereto. For example, if the non-ampholytic polymer is oxidized by light or air, photooxidation may occur, and a defect formed in the skeleton of the non-ampholytic polymer by the generated photo-oxidation may cause the nanowire of the non- But may not be limited thereto.

In one embodiment of the present invention, the non-amorphous polymer film may be applied to, but not limited to, an optoelectronic device such as a field effect transistor (FET), an organic light emitting diode, or a solar cell.

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples are given to aid understanding of the present invention, and the present invention is not limited to the following examples.

[Example]

Materials and methods

All chemicals were purchased from Sigma Aldrich, Daejung and Fisher Scientific and used without further purification. Freshly distilled tetrahydrofuran (THF) was prepared by distilling THF over sodium metal and benzophenone.

NMR ( ¹ H nuclear magnetic resonance) spectrum was measured by a Bruker AVANCE III 3000 FT-NMR 300 MHz spectrometer using tetramethylsilane (TMS) as an internal standard and chloroform (CDCl ₃ ) substituted with deuterium as a solvent ≪ / RTI > Gel-permeation chromatography (GPC) was carried out on a Shimadzu liquid chromatography system using THF as the eluent at a flow rate of 1.0 mL / min. The column temperature was set at 40 占 폚 and polystyrene standards were used for MW analysis. UV-vis absorption spectra were obtained using an Agilent 8453 UV-visible spectrophotometer. TEM data was obtained with an accelerating voltage of 200 kV in JEOL JEM-2100F. Electrical measurements were performed using a semiconductor characterization system (Keithley, 4200-SCS) at ambient temperature in room temperature.

1-1. Synthesis of P3HT

Regioregular poly (3-hexylthiophene), P3HT, was synthesized by GRIM (grignard metathesis) polymerization using the same reaction conditions as previously reported. Fig. 1 is a chemical formula showing the polymerization of P3HT. An oven-dried 250 mL 3-necked round bottom flask was connected to the vacuum with an adapter to remove residues in the flask. The entire system was then purged with nitrogen gas. A solution of 2,5-dibromo-3hexylthiophene [2,5-dibromo-3hexylthiophene, 1.79 g (1 eq, 5.49 mmol)], freshly distilled 10 mL THF, and tetra-butylmagnesium chloride [ 5.49 mL, 1.0 M (1 eq, 5.49 mmol)] was added to the flask and stirred for about 90 minutes to activate the monomers. The color of the solution changed from light yellow to light brown. Add 40 mL of THF and 56 mg in (0.02 eq, 0.111 mmol) dichloro (1,3-bis (diphenylphosphino) propane) nickel (Ni (dppp) Cl ₂₎ in the [dichloro (1,3-bis ( diphenylphosphino) propane) nickel (Ni (dppp) Cl ₂ ) was added to the flask and stirred at room temperature for 20 minutes. To stop the polymerization reaction, 200 mL of methanol was added to the reaction flask, which precipitated the polymer product into a purple color. The product was filtered through a soxhlet thimble and methanol, hexane Soxhlet extraction was performed to remove the oligomer, and then Soxhlet extraction with chloroform was performed to finally obtain the polymer. After the Soxhlet extraction with chloroform, the product was redissolved in each distilled THF and any residual Ni catalyst in the solution was passed through an alumina column. The final product was 0.43 g, which corresponds to a 47% yield.

1-2. Characterization of P3HT

Polymer P3HT synthesized by GRIM polymerization (characterization by the grignard metathesis polymerization method) was characterized by NMR (Fig. 2) and GPC (Fig. 3) and the molecular weight and polydispersity index were determined. Figures 2 and 3 show ¹ H NMR spectra and GPC chromatograms (SPD trace, 450 nm) of P3HT synthesized respectively. Because coil-type polystyrene standards were used for MW analysis, GPC overestimates the molecular weight of P3HT. Thus, the GPC data was calibrated using two calibration factors, which is consistent with the data in the literature. The degree of polymerization of P3HT was independently confirmed by NMR by comparing the signal of the thiophene ring at 6.98 ppm with the 6.80 ppm signal at the polymer end group. The concentrations of the synthesized polymers were estimated from UV-vis absorption spectra using Beer's law.

^{1 H NMR (300 MHz, CDCl} 3): δ H 0.91 (t, 3H), 1.37-1.42 (m, 6H), 1.59-1.71 (m, 2H), 2.80 (t, 2H), 6.98 (s, 1H ).

2-1. Preparation of non-amorphous polymer membrane: Self-assembly of P3HT at the liquid-air interface

Generally, P3HT was dissolved in toluene at a concentration of 50 [mu] M, and 100 [mu] L of the orange polymer solution thus obtained was gradually dropped from the glass Petri dish to the water surface. The Petri dish was closed with the lid and left overnight to allow the solvent to evaporate slowly (Figure 4). After overnight incubation, a pale pink thin film was formed on the surface of the water.

The polymer membrane was transferred onto a TEM grid for structural analyzes. As shown in Fig. 5 (a), the P3HT ultra thin film was macroscopically uniform. High magnification images indicate that the thin film is formed of well-aligned nanowire arrays (FIG. 5 (b)). The nanowire width was measured from image J fast Fourier transform (FFT) images (FIG. 5C) to 8.0 +/- 0.9 nm (FIG. 5D) And the contour length of the P3HT (7.7 nm). The thickness of the film was measured to be 4.0 +/- 0.3 nm by ellipsometry, which corresponds to about two to three layers of P3HT. These values are consistent with those reported in the literature for self-assembled P3HT nanowires in solution, which generally range from 12 nm to 17 nm and do not vary significantly with (width) molecular weight. Based on this data, the present inventors present a structural model in which an interfacial self-assembly process leads to packing P3HT strands into one-dimensional wires, which, as shown in FIG. 5 (e) Dimensional nanowires form aligned nanowire arrays. 5 (d), the sorted domain size is a micrometer scale, the vertically aligned domains are red, the horizontally aligned domains are blue, and the middle aligned intermediate alignment) is displayed as a color sequence of red to blue.

It is difficult to produce molecularly thin and uniform films using conventional techniques such as conventional spin-coating, and thus, the present invention provides a thin film manufacturing method that enables nanowire assembly at the same time as polymer packing.

Interfacial self-assembly was used to fabricate conductive polymeric membranes with controlled morphology. For example, Kim et al. Can use a Langmuir-Blodgett (LB) technique to obtain a thin film having a controlled packing structure and orientation at the water surface by self-assembly of an amphoteric conductive copolymer Respectively. In these studies, the amphiphilic nature of the polymer appeared to be critical for controlled self-assembly. This technique has been successfully applied to polythiophenes having either hydrophilic side chains or exceptionally hydrophobic fluoroalkyl side chains. However, it is easy to produce highly ordered assemblies by the LB technique, except that the non-amphoteric P3AT species are mixed with a surfactant such as stearic acid, dodecanol or polar liquid crystals to form a stable monolayer I do not. The results presented here demonstrate that it is, in fact, possible to form polymer thin films aligned at the air-liquid interface only from the non-amphoteric P3HT homopolymer.

2-2. Factors affecting the self-assembly of P3HT at the liquid-air interface

Self-assembly of non-ampholytic polymers with concentration of polymer-containing solution

Self-assembly of the P3HT was sensitive to the concentration of the polymer solution (FIG. 6). When the polymer concentration was too low, sparsely aligned short nanowires were found in the TEM image (Fig. 6 (a)). When the polymer concentration is too high, entangled polymer membranes are formed, as shown in Figures 6 (c) and 6 (d). Well-aligned densely packed nanowire arrays formed at the optimal intermediate concentration are shown in Figure 6 (b) for comparison.

Self-assembly of non-ampholytic polymers according to molecular weight of polymer

Molecular weight-dependent self-assembly was also performed to identify optimal conditions for dense nanowire packing. To confirm the effect of molecular weight, interfacial self-assembly was carried out using high molecular weight P3HT ₃₀₀ (Mn ~ 50 kDa). The polymer membrane was formed at a higher rate than short P3HT. As shown in Fig. 7 (b), partially disordered nanowire films were formed, and compared to the self-assembled films of low molecular weight P3HT, a cluster structure was frequently found (Fig. 7 (a)). In addition, the width of the high molecular weight nanowires (~16.4 ± 1.4 nm) was much narrower than the outer length (~ 116 nm) of P3HT ₃₀₀ . This is consistent with the typical chain folding of high molecular weight P3HT. When the molecular weight of the P3HT was increased beyond the critical point (~ 10 kDa), the self-assembled P3HT nanowires exhibited a constant wire width of about 16 nm. Taking into consideration the uniformity of the thin film in the wide area and dense nanowire packing, using a relatively short P3HT chain was advantageous for the production of ALISA thin films of P3HT homopolymer.

Self-assembly of non-ampholytic polymers according to the type of subphase

In addition, in order to test how the characteristics of the subphase affect self-assembly, as a comparative example, in addition to water, several different subphases (diethylene glycol, DEG, triethyleneglycol monoethyl ether ether, TGEE), and glycerol] have been employed for interfacial self-assembly. The different subphases were used instead of water. The DEG and TGEE have often been used as subphases for interfacial self-assembly of hydrophobic nanoparticles using their low vapor pressure. However, as shown in Figs. 8 (a) and 8 (b), the polymer films formed in DEG or TGEE mostly consist of nanowires that are agglomerated. The subphase-dependence of the present application was considered to be a result of their viscosity. The viscosities of DEG (38 mPa s, 20 캜) and TGEE (44.9 mPa s, 25 캜) are much higher than water viscosity (1.00 mPa s, 20 캜). Thus, the ordered formation of structures in these subphases is not as efficient as water. To further test the hypothesis that sub-phase mobility plays an important role, polymer self-assembly was performed at glycerol (942 mPa s, 25 캜), a high viscosity liquid. Interestingly, TEM images indicate that the membranes formed in glycerol are composed of small particles of P3HT and that the secondary structure of the nanowire is not observed on glycerol as a subphase (Fig. 8 (c)). These results support our hypothesis that the fluid properties of the water surface are important for the formation of well-aligned nanowire arrays of P3HT.

Self-assembly of non-ampholytic polymers by oxidation

The photo-oxidation of P3HT also plays an important role in the ordered assembly structure. When the polymer solution was exposed to air and light, pure P3HT was decomposed. Under these conditions, the photooxidation of P3HT forms a defect in the polymer backbone, and the formed defect hinders the packing of the polymer nanowire. The decomposition of the polymer was confirmed by a decrease in the absorption coefficient and a slight blue shift of the absorption peak (Fig. 9 (a) and Fig. 9 (b)). Compared to TEM images of membranes using freshly prepared P3HT polymers (Figure 9 (c)), TEM images of thin films prepared from degraded polymers exhibit a disordered morphology with partial coverage of nanowires d)]. Obviously, defects in the conjugated polymer backbone interfere with the alignment of the polymeric packings and the polymeric nanowires. Therefore, in order to pack the non-ampholytic polymer and facilitate the formation of nanowires, it is suitable to minimize the exposure of the non-ampholytic polymer solution to light or air.

3-1. Measurement of electrical migration of non-ampholytic polymer membrane

Electrical measurements were performed on self-assembled P3HT thin films prepared at the air-water interface. 10 (a) shows a schematic view showing a structure of a FET using a P3HT ALISA film as an electrical channel. Here, drain and source electrodes (10 nm thick Ti phase 30 nm thick Au) with Ti / Au were first fabricated on a Si / SiO ₂ substrate (3000 A, Silicon Materials Inc.). That is, the metal electrode was patterned by photolithography, thermal deposition and lift-off processes. The patterned device was cleaned by chloroform and acetone for 10 minutes and maintained in a UV-ozone cleaner for 20 minutes. The device was then immediately transferred to a vacuum desiccator and held for 2 minutes in an autoclave (100 mmTorr) with 3 mL of hexamethyldisilazane (HMDS, Aldrich, > 99% Respectively. After HMDS treatment, the device was washed with chloroform and acetone, and the surface was blown dry with a weak N ₂ flow. The P3HT nanowire film was prepared by the above-mentioned method, and the ALISA film was transferred to the device floating on the water through the horizontal immersion of the device and transferred to the device.

The thickness of the film was calculated by the ellipsometry measurement (Alpha-SE, JA Woollam). The transfer characteristics were measured by a semiconductor characterization system (4200-SCS, Keithley) at ambient conditions. The field effect mobility can be calculated from the equation: = (d I _DS / d V _G ) [L / (W C _OX V _DS )] where L is the channel length (2 μm) (40 μm), and C _OX = 1.476 × 10 ^-8 F / cm ² is the gate capacitance. The thickness of the SiO ₂ layer is 300 nm. The transconductance, d I _DS / d V _G , was determined by extrapolating the I _DS -V _G curve at V _DS = 20 V from the maximum slope point.

10 (b) shows the current density (J _DS ) vs. drain-source voltage (V _DS ) characteristics of the ALISA film and the FET with the spin-cast film channel. The current was measured at different gate biases (V _G ) from -100 V to 0 V. Both films exhibited p-type semiconductor behavior and exhibited higher currents at higher gate biases. The FET with the ALISA film (top curve) exhibited a higher current density than the current density of the spin-cast film (bottom curve). The analysis shows that the ALISA film has a conductivity 10 times higher (~ 5.1 × 10 ^-3 S / cm) than the spin-cast film (~ 4.7 × 10 ^-4 S / cm). This conductivity value of the ALISA membrane was much higher than the conductivity values of other nanowire-based P3HT membranes reported in prior studies [Xu, G .; Bao, Z .; Groves, JT, Langmuir-Blodgett films of regioregular poly (3-hexylthiophene) as field-effect transistors. Langmuir 2000, 16 (4), 1834-1841], [Nagano, S .; Kodama, S .; Seki, T., Ideal spread monolayer and multilayer formation of fully hydrophobic polythiophenes via liquid crystal hybridization on water. Langmuir 2008, 24 (18), 10498-10504]. Presumably, the high quality-crystalline structure in the nanowire structure reduces possible defects of the ALISA film of the present invention, leading to improved conductivity.

10 (c) shows the gating characteristics (J _DS -V _G ) of the ALISA film and the spin-cast film channel. The gate bias was swept from -100 V to 100 V. In other words, both of the films exhibited p-type behavior, and the gate bias (V _G ) showed an increasing current density toward a higher negative voltage. However, the change in J _DS was greater (~ 10 ² times) in the nanowire film, which meant higher hole mobility than the hole mobility of the spin-cast bulk film. In the measurement of the present invention, the mobility values of the ALISA film and the spin-cast film were calculated to be 3.5 × 10 ^-2 and 1.5 × 10 ^-3 cm ² / V · s, respectively. This indicated that the nanowire structure actually enhanced the mobility of the hole carriers in the film. The mobility values of the ALISA membranes were 10-fold or 100-fold higher than the mobility values of other membranes based on P3HT polymers having similar molecular weights [Han, Y.; Guo, Y .; Chang, Y .; Geng, Y .; Water, Z., Chain Folding in Poly (3-hexylthiophene) Crystals. Macromolecules 2014, 47 (11), 3708-3712.], [Dong, A .; Chen, J .; Vora, PM; Kikkawa, JM; Murray, CB, Binary nanocrystal superlattice membranes self-assembled at the liquid-air interface. Nature 2010, 466 (7305), 474-477]. In addition, the mobility values of the ALISA membranes herein are ~6 times higher than the mobility values of the nanowire membranes consisting of the previously reported conductive and insulating nanowires (Cativo, MHM; Kim, DK; Riggleman, RA; Yager, KG; Nonnenmann, SS; Chao, H .; Bonnell, DA; Black, CT; Kagan, CR; Park, S.-J., Air.Liquid Interfacial Self-Assembly of Conjugated Block Copolymers into Ordered Nanowire Arrays. ACS nano 2014, 8 (12), 12755-12762]. This result shows that the absence of an insulating block in the ALISA film of the present invention, which is important for versatile applications such as FETs and sensors, actually improved mobility.

11 (a) to 11 (f) show the solvent annealing effect of P3HT _{30 on} the ALISA film, in which nanowires (a) assembled without solvent vapor and nanowires assembled with solvent vapor saturated in the chamber, (b). 11 (c) and 11 (d) show orientation color maps of the above (a) and (b), respectively, and the red, orange, yellow, green, blue, indigo, and purple The statistical data calculated from the image according to each color are shown in Figs. 11 (e) and 11 (f). As shown in FIG. 11, it can be seen that the alignment of the P3HT polymer nanowire arrays produced through solvent annealing is improved.

Preparation of multilayer non-ampholytic polymer membranes

First, a monolayer type non-amorphous polymer membrane was prepared using the same method as described in the above example. Next, a solid substrate is prepared, and then a monolayer non-ampholytic polymer film formed on the substrate and the sub-phase liquid surface is stacked in parallel to transfer the polymer film onto the substrate to coat the solid substrate. Alternatively, The dope is vertically dipped in the phase liquid and then vertically pulled up to transfer the non-ampholytic polymer film formed on the surface of the substrate to the surface of the substrate to coat the polymer film of the monolayer type , And vacuum was used to remove the remaining sub-phase liquid on the substrate. Thereafter, a polymer film in the form of a mono-layer is additionally transferred and coated on the substrate having the polymer film stacked one upon the other, and then laminated, and then the remaining sub-phase liquid is removed using vacuum to thereby achieve the thickness of the final target polymer film The polymer monolayer was laminated by one or more layers to prepare a multilayered non-ampholytic polymer membrane.

In the present application, we have applied the ALISA approach to non-amphoteric P3HT nanowires and demonstrated that interfacial assembly enables simultaneous packing and alignment of P3HT, leading to ultra thin films of aligned conductive nanowires with improved electrical properties . The assembly of the P3HT homopolymer has advantages over the assembly of the block copolymer due to their simple synthesis and purification. Also, the removal of the insulating block can lead to better performance when implemented in an electrical device.

The present application also shows that subphase liquid-air interface self-assembly of an amorphous P3HT can lead to a polymeric ultra-thin film formed of a well-aligned P3HT nanowire array. Since the non-amphoteric conjugated polymer is easier to synthesize than the amphiphilic block copolymer, it is easy to obtain, and as a result, it is proved that the interfacial assembly can be applied not only to the amphiphilic block copolymer but also to the general non-ampholytic polymer These results are important because they can. In the present application, the selection of the sub-phase liquid and purity of the polymer sample is an important factor affecting the self-assembly. The fluidity of the liquid surface allows for reconstitution and removal of the thermally trapped defects in the polymer membrane, which leads to a uniform aligned membrane on the micrometer scale. The P3HT film formed on the water surface exhibited higher mobility than the spin-cast films and other P3HT nanowire-based films reported in previous studies. These results extend the usability and applicability of interfacial self-assembly.

It will be understood by those of ordinary skill in the art that the foregoing description of the embodiments is for illustrative purposes and that those skilled in the art can easily modify the invention without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be interpreted as being included in the scope of the present invention.

Claims (12)

Dropping the non-ampholytic polymer-containing solution onto the subphase liquid surface; And
The non-ampholytic polymer film is formed as the solvent of the non-ampholytic polymer-containing solution evaporates at the sub-phase liquid-air interface
Wherein the non-ampholytic polymeric membrane is a polymeric membrane.
The method according to claim 1,
And the non-ampholytic polymer film is formed as the non-ampholytic polymer is self-assembled at the sub-phase liquid-air interface.
The method according to claim 1,
Wherein the non-ampholytic polymer film comprises an array of nanowires of the non-ampholytic polymer.
The method according to claim 1,
Wherein the non-ampholytic polymer is a homopolymer.
The method according to claim 1,
Wherein the non-ampholytic polymer comprises a polymer selected from the group consisting of polythiophene series, polyparaphenylene vinylene series, and combinations thereof.
The method according to claim 1,
Wherein the subphase liquid comprises a material selected from the group consisting of water, diethylene glycol, triethylene glycol monoethyl ether, glycerol, and combinations thereof.
The method according to claim 1,
Wherein the concentration of the non-ampholytic polymer-containing solution is 10 [mu] M to 100 [mu] M when forming a monolayer.
The method according to claim 1,
Wherein the non-ampholytic polymer has a molecular weight of 1 kDa to 10 kDa.
9. An amorphous polymer membrane produced according to the method of any one of claims 1 to 8.
10. The method of claim 9,
Wherein the non-ampholytic polymer film has a thickness of 1 nm to 20 nm.
10. The method of claim 9,
Wherein the non-ampholytic polymeric membrane comprises an array of nanowires of the non-ampholytic polymer.
10. The method of claim 9,
Wherein the non-ampholytic polymer comprises a polymer selected from the group consisting of polythiophene series, polyparaphenylene vinylene series, and combinations thereof.

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