WO2018169236A1 - Polydimethylsiloxane polymer using aziridine and preparing method therefor - Google Patents

Abstract

The present invention relates to a polydimethylsiloxane polymer using aziridine and a preparing method therefor.

Description

Polydimethylsiloxane Polymer Using Aziridine and Manufacturing Method Thereof

The present invention relates to a polydimethylsiloxane polymer using aziridine, a three-membered cyclic compound, and a preparation method thereof.

The rapid increase in the complexity of technologies to address health, energy and environmental issues has driven the demand for materials with custom properties at the molecular level. Such materials can be prepared by incorporating clickable moieties (moieties that can be combined with other functional groups) into the substrate in a simple and high yield. Thus, the technology of building custom materials with ring-modified organic cyclic compounds has attracted attention for decades. The organic cyclic compounds on and / or on the surface of the materials allow for further chemical reactions through their ring opening reactions and can induce structural modifications of various types of biological or non-biological substrates for individual applications.

Ternary O-heterocyclic epoxides have received particular attention in developing functional polymeric materials. The delicate ring structure of epoxides can be easily opened in the presence of nucleophiles. These features are actively used in many categories of polymer material development, including adhesives, surface coatings, self-healing materials and matrices for making nanometer-sized materials. However, epoxide has a problem that the ring opening reaction occurs by being promoted by water.

The ring-opening reaction of epoxides usually depends on amine-based nucleophiles. Aziridine is a ternary N-heterocyclic compound that is structurally similar to epoxide, but differs greatly in chemical properties. The chemical and regioselectivity of aziridine for the ring-opening reaction is programmable by regulating the electronic structure and steric hindrance of substituents on the nitrogen of two sp3 carbons and aziridine. In addition, aziridine can be structurally robust designed even at ambient conditions, including harsh conditions such as high temperature and acidic / basic conditions. Despite the long history of using aziridine in organic synthesis, the use of aziridine in materials science has rarely been achieved.

The inventors of the present invention have focused on polydimethylsiloxane as a polymer support. PDMS is widely used in technology requiring organic polymers because it is optically transparent, flexible, inexpensive, commercially available, and non-toxic. This unique feature allows PDMS to be applied to flexible displays and electronics or lab-on-a-chips. As the need to realize complex technologies using PDMS increases, much effort is being made to develop PDMS analogs with fine-tunable chemical properties at the molecular level. The general strategy is for post-modification of PDMS surfaces using oxygen / ultraviolet treatment, chemical click reactions and methods of mixing nanometer-sized particles into PDMS. PDMS analogs formed through this strategy often suffer from the loss of original optical and / or elastomeric properties. Another strategy is to prepare PDMS derivatives with the desired functions based on the synthesis of new siloxane monomers having functional groups and their polymers. This strategy allows the design of PDMS structures at the molecular level and allows for relatively uniform compositions and structures across the sample. Several clickable moieties such as azide and thiols have been incorporated into PDMS by polymerizing siloxane monomers containing these moieties, but it has been difficult to represent a wide range of substrates as well as clickable PDMS based on simple, efficient and direct click reactions.

[Preceding technical literature]

(Patent Document 1) Republic of Korea Patent Publication No. 10-2006-0003749

(Patent Document 2) Republic of Korea Patent No. 10-16314781

The present invention is to provide a polydimethylsiloxane polymer using aziridine, a three-membered cyclic compound, and a preparation method thereof.

The present invention provides a polymer represented by the following [Formula 1] to solve the above problems.

[Formula 1]

In [Formula 1], a is an integer of 1 to 20, b is an integer of 0 to 20, c is an integer of 1 to 20, l is an integer of 1 to 20, m is an integer of 1 to 20. to be.

In addition, the present invention by reacting the compound represented by the following [Formula 2], the compound represented by the following [Formula 3] and the compound represented by the following [Formula 4] under a karstedt 'catalyst It provides a method for producing a polydimethylsiloxane-based polymer having an aziridine group comprising the step of preparing a polymer represented by 1].

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 1]

In [Formula 1] to [Formula 4], a is an integer of 1 to 20, b is an integer of 0 to 20, c is an integer of 1 to 20, l is an integer of 1 to 20, m is It is an integer of 1-20, and a + b + c = n.

The manufacturing method according to the invention can be used for the production of customized PDMS. The method for producing clickable PDMS (aziPDMS) according to the present invention can be prepared using a simple, general PDMS curing process without damaging the ring structure of aziridine. In addition, the orthogonal ring-opening reaction of aziridine according to the present invention is efficient for the post-modification of the polymer support (PDMS) having a wide substrate range. Post-modification of PDMS through the ring opening reaction of aziridine according to the present invention is not limited to the surface, but also possible in internal pores, and may be performed in a region-specific manner. In addition, the programmable reactivity and chemical selectivity of aziridine allow the design of advanced materials that respond to the desired reaction conditions.

In addition, PDMS comprising aziridine covalently linked (aziPDMS) may be post-modified by orthogonal ring-opening reaction of aziridine with carboxylic acid, alcohol, amine or thiol. This post-modification characterizes the ring-opened aziPDMS by using photoluminescent and fluorinated molecules on the macroscopic and molecular scale, respectively, through ultraviolet irradiation and XPS specificity. The amount inside the PDMS scaffold is directly adjustable. The customized PDMS and its manufacturing method according to the present invention are unprecedentedly attractive and efficient, requiring molecularly controlled functions such as flexible displays, nano ink pens, biomedical sensor chips, optical materials and contact charging surfaces. It can be usefully applied to construct functional materials and devices.

Figure 1a is a structure of a compound used to prepare a polydimethylsiloxane-based polymer comprising aziridine according to the present invention.

Figure 1b is a schematic of the post-modification through the production and ring-opening reaction of the polydimethylsiloxane-based polymer (aziPDMS) containing aziridine.

1C is a static contact angle image (right) of Comparative Example 1 (PDMS) and Example 1.6 (aziPDMS) film photo (left) and water droplets according to the present invention (right).

1D shows the results of irradiation scans of PDMS (gray, control) and aziPDMS (black line) obtained by X-ray photoelectron spectroscopy (XPS).

1E is an XPS depth profile result obtained through in situ etching of aziPDMS.

FIG. 2A shows the Comparative Example 1 (PDMS) and Example 1.6 (aziPDMS) films incubated in 2.5 mM 5 (6) carboxyfluorescein solution, followed by visible light (above) and 254 nm UV light (below). ). aziPDMS emits a significant amount of fluorescence, while PDMS emits little fluorescence.

FIG. 2B is a strength-elongation curve of PDMS and aziPDMS fibers before and after ring opening with a carboxylic acid compound (5 (6) -carboxyfluorescein).

Figure 2c is a result showing the image of the ring-opening aziPDMS fibers of the present invention according to different elongation.

Figure 2d shows the result of post-modification using 5 (5) -carboxyfluorine after preparing the PDMS / aziPDMS laminated structure. Selective post-modification was observed in the aziPDMS region.

3A is an image of aziPDMS containing different amounts of aziridine (base: curing agent: aziridine 1 = 10: 1: x with vinyl at the end, where x is 0 to 0.15).

3B is the UV absorption spectrum of aziPDMS film. As the aziridine content increased, the absorption strength increased.

Figure 3c is a photograph of the aziPDMS film taken after the ring-opening reaction incubated in 2.5 mM 5 (6) -carboxyfluorescein.

3D is the photoluminescence emission spectrum result of the ring-opened aziPDMS film. Figure 3e is a measure of the substrate range of aziPDMS through XPS measurement, a result of incorporating various fluorinated carboxylic acid, alcohol, amine and thiol derivatives into aziPDMS through aziridine ring opening reaction. Inset graph shows high resolution spectral results of the F1s region for PDMS (control) and ring-opened aziPDMS.

4A confirmed the structural specificity (surface vs. internal) of aziPDMS via post-modification by controlling the polarity of the solution for low-wetting PDMS. aziPDMS cubes (1 cm × 1 cm × 1 cm) were prepared separately from 0.25 mM 5 (6) -carboxyfluorescein solution (yellow; CHCl ₃ : MeOH = 1: 5, v / v) and 0.25 mM 7- A sample obtained by continuously incubating and slicing in hydroxycoumarin (blue; HCl ₃ : MeOH = 5: 1, v / v) is an image taken by irradiating visible and ultraviolet rays.

Figure 4b is a result of confirming the post-modified surface depth of aziPDMS according to the polarity of the solution. As the amount of methanol decreased, the surface depth increased after the first modification (yellow region).

4C is a plot of% surface depth as a function of volume ratio of methanol in solution (defined as the ratio of surface depth after first modification to half width of the entire film).

FIG. 5 shows a schematic of the Pt (0) -catalyzed hydrosilylation between aziridine 1 and PDMS prepolymer having a vinyl group at the end.

FIG. 6 shows the results of ¹ H NMR spectroscopy of Pt (0) -catalyzed hydrosilylation and ring-opening reaction of aziridine and benzoic acid between silyl hydride (curing agent B) and aziridine (1) having a vinyl group at the end. . Curing agent B, which is a commercial reagent, may be added with a small amount of an additive, and thus a peak may be detected.

FIG. 7 shows photoluminescence spectra of aziPDMS incubated in 5 (6) -carboxyfluorescein (red) and 2.5 mM 5 (6) -carboxyfluorescein (black) solutions in methanol.

FIG. 8 is a result of applying a thresholding technique for the cut aziPDMS film in FIG. 4B.

The inventors of the present invention have completed the present invention by developing a method of introducing aziridine onto a molecular substrate and using a ring-opening reaction of aziridine in order to devise a customized polymer support at the molecular level. Specifically, the present invention provides a custom-made PDMS (hereinafter referred to as aziPDMS) functionalized by aziridine prepared by curing a conventional PDMS prepolymer (Sylgard 184 Silicone elastomer kit) in the presence of aziridine with vinyl at the end and a method for preparing the same. .

Hereinafter, the present invention will be described in more detail.

The present invention provides a polymer represented by the following [Formula 1].

[Formula 1]

In [Formula 1], a is an integer of 1 to 20, b is an integer of 0 to 20, c is an integer of 1 to 20, l is an integer of 1 to 20, m is an integer of 1 to 20. to be.

In the present invention, the polymer of [Formula 1] may be ring-opened by reacting with a compound containing a carboxylic acid, alcohol, amine group or thiol group, the carboxylic acid, alcohol, amine group to the ring-opened aziridine moiety Or a compound containing a thiol group may be attached.

According to the present invention, the polymer of [Formula 1] is characterized by retaining elasticity, it can be easily stretched up to 250%.

According to the present invention, the polymer of [Formula 1] is improved in light weight and mechanical elasticity without loss of optical and mechanical properties compared to the conventional PDMS.

In addition, aziridine-functionalized PDMS according to the present invention (aziPDMS) can be easily synthesized from readily available prepolymers.

The present invention reacts the compound represented by the following [Formula 2], the compound represented by the following [Formula 3] and the compound represented by the following [Formula 4] under a karstedt 'catalyst (Formula 1) It provides a method for producing a polydimethylsiloxane-based polymer having an aziridine group, including the step of preparing a polymer represented by.

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 1]

In [Formula 1] to [Formula 4], a is an integer of 1 to 20, b is an integer of 0 to 20, c is an integer of 1 to 20, l is an integer of 1 to 20, m is It is an integer of 1-20, and a + b + c = n.

According to the present invention, the reaction may be a thermosetting reaction carried out at 50 to 100 ℃ for 0.5 to 3 hours.

According to the present invention, the compound of [Formula 4] may be prepared by reacting (1-benzylaziridin-2-yl) methanol with chlorodimethyl (vinyl) silane at 40 to 80 ° C., preferably a base It may be reacted in the organic solvent in the presence. The base may be triethylamine, but is not limited thereto. The organic solvent may be an organic solvent selected from methylene chloride, tetrahydrofuran, N, N-dimethylformamide, dimethyl sulfoxide, toluene, ethanol, methanol, ethyl acetate and ether, but is not limited thereto. Toluene.

According to the present invention, the (1-benzylaziridin-2-yl) methanol is reacted with ethyl 2,3-dibromopropanoate in the presence of a base such as benzylamine in a nitrogen stream and triethylamine. Preparing benzylaziridine-2-carboxylate; And reacting the ethyl 1-benzylaziridine-2-carboxylate with lithium aluminum hydride.

According to the present invention, with respect to 10 parts by weight of the compound represented by [Formula 2], 0.5 to 2 parts by weight of the compound represented by [Formula 3] and 0.02 to 0.2 parts by weight of the compound represented by [Formula 4] It may be to. When the content of the compound represented by the above [Formula 4] is less than the above range, the clickable portion is too small, so that post-modification is not easy, and it is difficult to exhibit elasticity. On the other hand, if the above range is exceeded, a serious interference phenomenon occurs in the crosslinking between the base and the curing agent, and the transparency is lost, and powder or oily opaque polymer is produced, which is not preferable.

The compound represented by the above [Formula 1] according to the present invention is reacted with a compound containing a carboxylic acid, alcohol, amine group or thiol group to ring-open the aziridine group of [Formula 1]; The compound containing the carboxylic acid, alcohol, amine group or thiol group may be attached to the moiety of the ring-opened aziridine.

The present invention has three features as follows.

(1) The manufacture of clickable PDMS can be prepared simply using a conventional PDMS curing process, without damaging the ring structure of aziridine.

(2) The post-modification of PDMS is not limited to the surface, but also inside the pores through the ring opening reaction of aziridine.

(3) Programmable reactivity, chemical selectivity, and a wide range of substrates of aziridine can be used to design aziridine-based materials that react to the desired reaction conditions.

In the present invention, the molecular substrate may be polydimethylsiloxane (PDMS).

According to the present invention, PDMS containing aziridine can be prepared by thermosetting the prepolymer in the presence of aziridine which is terminally vinyl. As shown in FIG. 1A, the prepolymer may include a base (part A) and a curing agent (part B) in a weight ratio of 8: 1 to 20: 1, and preferably in a 10: 1 weight ratio. Can be.

According to the present invention, the thermosetting may be performed at 80 ° C. for 2 hours, thereby obtaining a composite (aziPDMS) converted to PDMS having a covalently bonded aziridine pendant. The aziPDMS thus obtained may maintain optical transparency and mechanical elasticity of the existing PDMS.

Post-modification of aziPDMS can be achieved through the orthogonal ring-opening reaction of aziridine pendants (FIG. 1B). According to the invention, alcohols, amines, thiols and carboxylic acids can be used for the post-modification of aziPDMS.

The production process and structural modification reactions according to the invention are simple and effective and can be carried out using commercial reagents. Together with these advantages, the various and robust ring opening reactions of aziridine are useful for preparing custom polymeric materials.

Hereinafter, the present invention will be described in more detail with reference to Examples, but embodiments of the present invention disclosed below are exemplified to the last, and the scope of the present invention is not limited to these embodiments. The scope of the invention is indicated in the appended claims, and moreover contains all modifications within the meaning and range equivalent to the claims. In addition, "%" and "part" which show content in a following example and a comparative example are a basis of weight unless there is particular notice.

<Example>

<Reagent>

Unless otherwise specified, all reagents were purchased from commercially available reagents. Organic solvents were purchased from Daejeong (DAEJUNG, KOREA) and water was purified using Aqua MAX-Basic System (deionized water, electrical resistivity of ~ 18.2 MΩ · cm). Dow Corning's Sylgard 184 elastoemr kit was used.

<Device>

¹ H and ¹³ C NMR spectra were determined by Bruker FT-NMR Advance-500 using CDCl ₃ as solvent and residual solvent as internal standard. Chemical shifts are expressed in ppm relative to internal TMS, with a coupling constant (J) of Herz. MS (ESI-QTOF) measurements were measured with Bruker compat Q-TOF MS. All XPS measurements were performed on a Thermo Scientific K-Alpha XPS instrument with a monochromated Al K _α source. UV-vis spectra were measured using Agilent technologies-Agilent 8453 UV-Vis spectrometer. For UV-vis absorbance measurements, an intact PDMS film was used as the blank. The film thickness of the sample was kept constant (˜2 mm). The thickness of the sample inevitably causes errors at the microscopic level, but does not affect the overall tendency of λ _max as a function of the mass ratio of aziridine. Photoluminescence spectra were measured using a Hitachi F-7000 Fluorescence spectrophotometer. Tensile strength of PDMS and aziPDMS was measured using a Universal Testing Machine (UTM; WL 2100).

Synthesis Example  1.1- benzyl -2-((( Dimethyl (vinyl) silyl ) Oxy )- methyl Synthesis of Aziridine (1)

Scheme 1

Synthesis Example  1.1. Ethyl 2,3- Dibromopropanoate

Ethyl acetate (16.3 mL, 150 mmol) was mixed with 75 mL of dichloromethane, and bromine (7.7 mL, 150 mmol) was slowly administered over 20 minutes under an inert atmosphere at 0 ° C. The reaction mixture was reacted at 0 ° C. for 1 hour and then further reacted at room temperature for 3 hours. After completion of the reaction, the reaction mixture was added with a saturated Na ₂ S ₂ O ₃ solution to terminate the reaction, and extracted with dichloromethane and water to obtain the desired compound from the organic layer. The analysis of the obtained compound was consistent with previously known data values. Yield 97% (37.6 g)

Synthesis Example  1.2. Ethyl 1- Benzylaziridine -2- Carboxylate

Benzylamine (3.4 mL, 30.8 mmol) was dissolved in 60 mL of anhydrous ethanol under a nitrogen stream at 0 ° C., and the compound of Synthesis Example 1.1 (8 g, 30.8 mmol) and trimethylamine (8.5 mL, 69.6 mmol) were sequentially added thereto. The reaction mixture was added at 0 ° C. and heated at 60 ° C. for 1 hour. After the reaction was completed, the solvent was removed and extracted with dichloromethane and water. The organic layer was dried with a desiccant (magnesium sulfate) and then distilled under reduced pressure. The concentrated mixture was purified by column chromatography to give the desired compound as a white solid. The analysis of the obtained compound was consistent with previously known data values. Yield 80% (6.2 g)

Synthesis Example  1.3. (One- Benzylaziridine -2-yl) methanol

After dissolving the compound of Synthesis Example 1.2 (6.2 g, 30.2 mmol) in 130 mL of diethyl ether, lithium aluminum hydride (2.29 g, 60.4 mmol) was slowly added, followed by stirring at room temperature for 3 hours. After the reaction was quenched by addition of water (2.3 mL), 15% aqueous NaOH solution (2.3 mL) and water (6.9 mL) were added, and the mixture was filtered. After the reaction mixture was extracted with ethyl acetate, the organic layer was dried with a desiccant and dried under reduced pressure to remove the solvent to obtain the desired compound in the form of a yellow powder. The analysis of the obtained compound was consistent with previously known data values. Yield 87% (4.31 g)

Synthesis Example  1.4. One- benzyl -2-((( Dimethyl (vinyl) silyl ) Oxy ) methyl Aziridine (1)

To 50 mL of toluene distilled at room temperature under a nitrogen stream, the compound of Synthesis Example 1.3 (5.5 g, 33.7 mmol) and triethylamine (5.0 mL, 36.1 mmol) were added, followed by chlorodimethyl (vinyl) silane (5.1 mL, 35.4 mmol). ) Was added slowly. The reaction mixture was heated to 60 ° C., reacted overnight, and then extracted three times with ethyl acetate. After the extracted ethyl acetate was mixed and washed with distilled water, water remaining in ethyl acetate was removed with anhydrous sodium sulfate and distilled under reduced pressure to obtain a yellow oil-like compound. Yield 92% (7.7 g)

¹ H NMR (500 MHz, CDCl ₃ ) δ 7.21-7.40 (m, 5H), 6.05-6.16 (m, 1H), 5.97-6.05 (m, 1H), 5.75 (dd, J = 20.1, 4.0 Hz, 1H ), 3.62 (dd, J = 11.1, 5.6 Hz, 1H), 3.53 (dd, J = 11.1, 5.6 Hz, 1H), 3.45 (s, 2H), 1.72-1.82 (m, 1H), 1.69 (s, 1H), 1.45 (d, J = 6.1 Hz, 1H), 0.18 (s, 6H);

¹³ C NMR (126 MHz, CDCl ₃ ) δ 139.1, 137.2, 133.3, 128.3, 129.9, 65.3, 64.3, 40.5, 31.2, -2.2, -2.3;

MS (ESI) m / z : [M + H] ⁺ calcd for C ₁₄ H ₂₂ NOSi: 248.1465; found: 248.1429.

Comparative example  One. PDMS  Produce

Sylgard 184 (Dow Corning) silicone elastomer kit with base and curing agent was used. A conventional synthesis method for preparing PDMS is to add a platinum catalyst to vinyl and Si-H. Specifically, the base and the curing agent are mixed at a weight ratio of 10: 1, and the mixture is left under reduced pressure for 2 hours to form internal bubbles. After the removal, it was prepared by curing at 80 ℃ for 2 hours.

Example  One. Manufacture of aziPDMS

aziPDMS was prepared using a known PDMS manufacturing method. As shown in FIG. 1A, aziPDMS was prepared by mixing the base (A), the curing agent (B), and the aziridine (1) having a vinyl group at the end thereof, and Sylgard 184 was used as a model elastomer. Specifically, 1-benzyl-2-(((dimethyl (vinyl) silyl) oxy) methyl) aziridine is poured into a polytetrafluoroethylene (PTFE) mold to remove the contained bubbles. The degassed was put into a vacuum desiccator for 20 minutes. The mixture was thermoset at 80 ° C. for 2 hours to prepare aziPDMS film.

In this case, base: curing agent: 1-benzyl-2-(((dimethyl (vinyl) silyl) oxy) methyl) aziridine was mixed in a 10: 1: X weight ratio, and X was contained in a range of 0.025 to 0.2 weight ratio. When X is larger than 0.2, crosslinking between the base and the curing agent is severely caused by aziridine having a vinyl group at a large amount of terminal, which is not preferable because a powder or oily opaque PDMS is produced.

Example 1.1 aziPDMS with X 0.025

Example 1.2 aziPDMS with X of 0.05

Example 1.3 aziPDMS with X of 0.1

Example 1.4 aziPDMS with X of 0.125

Example 1.5 aziPDMS with X of 0.15

Example 1.6 aziPDMS with X equal to 0.2

Example  2. Ring opening using carboxylic acid aziPDMS  Produce

AziPDMS films with different amounts of aziridine were placed in 2.5 mM 5 (6) -carboxyfluorescein solution (methanol: CH ₂ Cl ₂ = 1: 1; v / v) at room temperature for 18 hours (or 50 ° C). Incubation for 12 h at slightly higher temperature). Next, the resultant was washed with methanol and CH ₂ Cl ₂ to remove unreacted 5 (6) -carboxyfluorescein, followed by drying under a high temperature oven and vacuum.

Example  3. Fluorinated carboxylic acid, phenol, thiophenol and Amine  Ring opening using derivative aziPDMS  Produce

3,5-bis (trifluoromethyl) benzoic acid as fluorinated carboxylic acid, 2,3,4,5,6-pentafluorophenol as phenol, 2,3,4,5,6 as thiophenol Pentafluorobenzenethiol was used. The aziPDMS film was post-modified using various fluorinated nucleophiles in a manner similar to the method according to Preparation Example 3 using aziPDMS film using 5 (6) -carboxyfluorescein. aziPDMS was incubated in 20 mM THF solution of each fluorinated compound. For the amine derivative (4-trifluoromethylaniline), Lewis acid (10 mM of BF ₃ · OEt ₂ ) was added for post-modification. Post-modification of aziPDMS for amines with Lewis acids is due to the reduced nucleophilicity of the amines by fluorination.

Test Example  1. Silyl using 1H NMR Hydride With polymer (B in FIG. 1A; curing agent)  At the end Vinyl  Determination of reaction of aziridine having and ring opening reaction by benzoic acid

As shown in FIG. 5, the thermal curing process of the PDMS prepolymer is the basis for hydrosilylation crosslinking by Pt (0) catalyst between silylhydride and vinyl derivative.

As depicted in FIG. 1A, the Pt catalyst (Karstedt's catalyst, 1 mg, in a clean environment at room temperature) to confirm that the vinyl group of Compound 1 (aziridine with a vinyl group at the end) binds to silyl hydride in the presence of a Pt catalyst B (600 mg) was added to Compound 1 (120 mg, 0.48 mmol) in the presence of 0.001 mmol, 0.001%) and the reaction was confirmed by measuring the ¹ H NMR spectrum of the mixture which was stirred at 80 ° C. for 1.5 hours.

In FIG. 6 the black ¹ H NMR spectrum at the bottom is the result of the starting mixture, and the red ¹ H NMR spectrum at the top is the result after 1.5 hours of reaction. As shown in FIG. 6, the hydrosilylation reaction between Compounds 1 and B was confirmed through ¹ H NMR spectra. The chemical shifts of 5.75, 6.01 and 6.10 ppm corresponding to the vinyl protons of Compound 1 disappeared completely within 1.5 hours, confirming that the desired coupling reaction was very efficient. In addition, the aziridine ring structure was maintained after the reaction, and the chemical shifts corresponding to the aziridine residues (1.45, 1.69 and 1.77 ppm) were confirmed by being kept unchanged.

Next, it was confirmed whether the covalently bonded aziridine can perform an effective ring-opening reaction with the carboxylic acid derivative. The experiment was carried out using benzoic acid, which is a structurally simple compound. Benzoic acid (67.0 mg, 0.55 mmol) in dichloromethane (3 mL) was added to the aziridine functionalized prepolymer at room temperature for 13 hours. ¹ H NMR confirmed that the ring-opening reaction of aziridine completely disappeared the chemical shifts at 1.45, 1.69 and 1.77 ppm corresponding to the covalently bound aziridine protons, thus quantitatively completing the desired ring-opening reaction.

Test Example  2. X-ray photoelectron spectroscopy; XPS ) analysis

As shown in FIG. 1C, the apparent optical transparency of the aziPDMS of Example 1 and the PDMS of Comparative Example 1 was not distinguished. The surface wettability of aziPDMS of Example 1 and PDMS of Comparative Example 1 was similar (Δθ = 6 °).

For structural analysis using XPS, aziPDMS was immersed for 6 hours in hexane and dichloromethane without impurities, and then rinsed. As shown in FIG. 1D, a scan of aziPDMS showed Si2p (˜102 eV) and O1s (˜532 eV) signals corresponding to the PDMS backbone, and C1s (˜284 eV) and N1s corresponding to aziridine pendants. (~ 398 eV) signal appeared. As shown in Table 1, the atomic concentration (atomic%) of the calculated value and the experimental value was consistent in both PDMS and aziPDMS.

The depth profile XPD scan was performed by etching the aziPDMS surface (etching rate: ˜5 nm / min). The depth profile of aziPDMS showed the highest atomic percent of Si and O and the lowest atomic percent of c during etching. Interestingly, the atomic% of N1s in aziPDMS was constant during the measurement, which means that aziridine is present at the same surface and interior.

contents		atom%
		Si	C	O	N
PDMS	calcd (b)	25.0	50.0	25.0	0.0
	exptl (c)	29.4	43.9	26.7	0.0
aZiPDMS (a)	calcd (d)	24.6	50.7	24.6	0.1
	exptl (c)	27.3	47.6	24.6	0.5

(a). Base: Hardener: Weight ratio of the aziridine (1) whose end is vinyl 10: 1: 0.2

(b). Atomic% is calculated using (SiOC ₂ ) as a repeating unit

(c). The resulting data is the average of three measurements

(d). Molecular weight (Mw) of siloxane repeating units with or without aziridine pendant is 74

Test Example  3.5 (6)- Carboxyfluorescein  Ring opening aziPDMS Photoluminescence  Red shift of λmax in the spectrum

Surface depth was determined through image analysis using the threshold method. To determine the surface depth of the post-modification, aziPDMS was functionalized using two different photoluminescent ring-opening reagents in polar and nonpolar solutions. Photoluminescent images of the multifunctionalized aziPDMS film were obtained, the images were converted to grayscale images using software (ImageJ), and the grayscale images were analyzed based on single intensity values. The gray level intensity at each pixel was calculated as the average of the color values for the red, green and blue portions of the color image. Maximum entropy thresholds were applied to generate binary (black and white) images from grayscale images. Using this method, all image pixels can be classified as foreground (regions of the aziridine of the present invention ring-opened by 5 (6) -carboxyfluorescein) or background pixels. The percentage of surface depth after the first post-modification was determined by determining the ratio of the width of the white pixels (corresponding to the surface post-modification) to half the width of the film in the line, and estimated by averaging from each of at least 10 samples.

Post-modification of aziPDMS via ring opening of aziridine was first performed with carboxylic acid derivatives. Aziridine having an electron-donating substituent (benzyl N-substituent of the present invention) under a nitrogen atmosphere at a slightly higher temperature, such as 50 ° C., was subjected to ring opening by treatment with carboxylic acid without catalyst and additives.

The acidic protons of the carboxylic acids react with the lone pair of nitrogen atoms of the aziridine. This reaction produces an activated aziridinium structure followed by subsequent addition of carboxylate. The ring opening reaction of aziridine shows good chemical and regioselectivity and high yield (> 90%). In order to visualize the post-modification of aziPDMS, mapping analysis was performed by reacting aziridine in aziPDMS with 5 (6) -carboxyfluorine, a photoluminescent carboxylic acid derivative.

AziPDMS of Example 1.6 and PDMS of Comparative Example 1 were incubated in a 2.5 mM 5 (6) -carboxyfluorescein methanol: CH ₂ Cl ₂ = 1: 1 (volume ratio) solution for 18 hours at room temperature, followed by methanol and CH Unreacted 5 (6) -carboxyfluorine was removed by washing with ₂ Cl ₂ .

As shown in FIG. 2A, upon irradiation with ultraviolet (254 nm of mercury UV lamp; 24 W), aziPDMS of Example 1.6 emits photoluminescence easily observed with the naked eye, while PDMS of Comparative Example 1 emits photoluminescence. Did not release. The above results mean that the ring-opening reaction of aziridine and carboxylic acid is efficient and orthogonal.

As shown in FIG. 7, the photoluminescence spectrum of aziPDMS showed λ _max at ˜531 nm. The emission band shifted slightly red (Δλ _max = ˜10) compared to free 5 (6) -carboxyfluorescein in solution (λ _max = ˜521 nm in methanold). The red shift of λ _max is an indicator that identifies 5 (6) -carboxyfluorescein covalently bound to the backbone of aziPDMS, and the interaction between 5 (6) -carboxyfluorescein molecules linked to PDMS is λ _max . Because it induces a change.

Test Example  4. Elongation Evaluation

The elastic modulus of aziPDMS of Example 1.6 was measured before and after the ring-opening reaction of aziridine and 5 (6) -carboxyfluorescein to determine whether the elastic properties of aziPDMS of Example 1.6 changed during post-modification. FIG. 2B is a strength-elongation curve of PDMS and aziPDMS fibers before and after ring opening with a carboxylic acid compound (5 (6) -carboxyfluorescein). Tensile strength for untreated and ring-opened aziPDMS showed no significant change (˜ × 1.3) of 0.66 MPa and 0.51 MPa, respectively.

On the other hand, Figure 2c shows the image of the ring-opening aziPDMS fiber of the present invention according to different elongation, it was confirmed that it is sufficiently extended to 200%.

Test Example  5. Compatibility Study

In order to confirm whether the aziPDMS and the conventional PDMS according to the present invention are compatible, the PDMS and the aziPDMS were repeatedly thermally cured as shown in FIG. 2D to prepare a laminated structure. The laminated films prepared in order to perform mapping analysis on the entire structure were incubated in 5 (5) -carboxyfluorescein solution. As shown in FIG. 2D, photoluminescence was selectively observed in the aziPDMS region rather than the PDMS region, and it was confirmed that the aziPDMS region was selectively modified. Through the above results, it was confirmed that the ring opening reaction of aziridine in aziPDMS is efficient for the post-modification of the PDMS support.

Test Example  6. According to the aziridine content aziPDMS  Property evaluation

While maintaining the weight ratio of the base and the curing agent in the same manner as in Example 1, by adjusting the weight ratio x of the aziridine terminal is vinyl to prepare aziPDMS film having a different aziridine content inside aziPDMS, the characteristics according to the aziridine content Was evaluated.

Figure 3a is aziPDMS film according to Examples 1.1 to 1.5 showed a slight change in the optical transparency apparent. In addition, referring to the UV-vis absorption spectrum shown in Figure 3b, the intensity of the absorption band at 259 nm increased linearly with the amount of aziridine.

In order to confirm the ring-opening reaction according to the aziridine content gradient, the aziPDMS film according to Examples 1.1 to 1.5 was incubated in a 2.5 mM 5 (6) -carboxyfluorescein solution for 18 hours at room temperature, and then washed with chloroform and methanol. And dried under hot oven and vacuum. 3C is an image of the films taken under visible and UV irradiation. The photoluminescence intensity of ring-opened aziPDMS increased with increasing content of aziridine, which is vinyl at the end. As shown in Figure 3d through the above results, it was confirmed that the photoluminescence emission characteristic has a linear correlation with the content of aziridine.

Test Example  7. Substrate Range Assessment

As the substrate of the aziPDMS ring opening, compounds having various functional groups such as carboxylic acids, thiols, alcohols and amine derivatives can be used. In particular, since the fluorine atom gives a strong signal in the XPS measurement, it is easy to confirm whether or not the ring opening reaction of aziPDMS is by XPS. In the present invention, the fluorine-containing compound was used for the experiment.

AziPDMS of Examples 1.1 to 1.5 and PDMS of Comparative Example 1 were treated with THF solution of 0.25 mM fluorine-containing compound at room temperature for 3 or 6 hours, then washed with pure THF, CH ₂ Cl ₂ and methanol, Dry in oven and in vacuo. As shown in FIG. 3E, the F1s peak appeared in the XPS spectrum of the ring-opening aziPDMS, but was not detected in the PDMS. These results indicate a broad substrate range of ring opening reaction of aziridine after modification.

Test Example  8. Evaluation using surface wettability

As shown in FIG. 1C, conventional PDMS generally exhibits low wettability (static contact angle θ = ˜113 ° of water droplets). High dielectric constant liquids such as water and methanol show very low wettability, while low dielectric constant liquids such as n-hexane and chloroform diffuse into the majority of the area on the surface and expand PDMS. The surface wettability of these PDMS was used to further demonstrate the site specificity (surface to volume) post-modification of aziPDMS.

As shown in FIG. 4, after preparing aziPDMS into a cube (1 cm × 1 cm × 1 cm), a polar solution containing a photoluminescent compound (0.25 mM 5 (6) -carboxyfluorescein) at 50 ° C. for 12 hours ( Incubated in CHCl ₃ : MeOH = 1: 5 volume ratio), washed with pure CHCl ₃ and MeOH, and dried in a hot oven and in vacuo. The dried cubes were sequentially taken up in a lower polar solution (CHCl ₃ : MeOH = 5: 1 volume ratio) containing other photoluminescent compounds (0.25 mM 7-hydroxycoumarin which emits blue photoluminescence under 254 nm UV irradiation). Incubated. The cubes were washed with pure CHCl ₃ and MeOH, dried under hot oven and vacuum and shaved.

During ultraviolet irradiation, the cube showed yellow and blue photoluminescence on the surface and inside, respectively (FIG. 4A). This site-specific post-modification of aziPDMS was also confirmed in photoluminescent images of fragmented films. The surface depth of the post-modification can be controlled by forming a gradient in the polarity of the solution. 5 (6) -carboxyfluorescein, a photoluminescent compound, was dissolved in various volume ratios of CHCl ₃ : MeOH cosolvents (0: 100 to 60:40), and then cultured and washed with aziPDMS cubes, respectively. Was incubated in a nonpolar solution (CHCl ₃ : MeOH = 9: 1 volume ratio) to post-modify. Surface depth was estimated using the above image analysis method. As the volume of methanol in the solution decreased after surface modification, the modified surface depth increased, as shown in FIG. 4B. This trend can be confirmed by correlating the volume ratio of methanol (which is directly related to the polarity of the solvent) with the% surface depth defined as the ratio of the surface depth after the first modification to half the width of the entire surface (FIG. 4C). The% surface depth began to change at the point where the methanol ratio was 70%.

The customized PDMS and its manufacturing method according to the present invention are unprecedentedly attractive and efficient, requiring molecularly controlled functions such as flexible displays, nano ink pens, biomedical sensor chips, optical materials and contact charging surfaces. It can be usefully applied to construct functional materials and devices.

Claims (9)

1. A polymer represented by the following [Formula 1]:

   [Formula 1]

   

   In [Formula 1], a is an integer of 1 to 20, b is an integer of 0 to 20, c is an integer of 1 to 20, l is an integer of 1 to 20, m is an integer of 1 to 20. to be.
2. The method of claim 1,

   Reacting with a compound containing a carboxylic acid, an alcohol, an amine group or a thiol group, the aziridine group is ring-opened, wherein the compound is attached to the ring-opened aziridine moiety.
3. The method of claim 1,

   A polymer characterized by showing elasticity.
4. A compound represented by the following [Formula 2], a compound represented by the following [Formula 3] and a compound represented by the following [Formula 4] are reacted under a karstedt 'catalyst and represented by the following [Formula 1] A method for preparing a polydimethylsiloxane-based polymer having an aziridine group, including: preparing a polymer:

   [Formula 2]

   

   [Formula 3]

   

   [Formula 4]

   

   [Formula 1]

   

   In [Formula 1] to [Formula 4], a is an integer of 1 to 20, b is an integer of 0 to 20, c is an integer of 1 to 20, l is an integer of 1 to 20, m is It is an integer of 1-20, and a + b + c = n.
5. The method of claim 4, wherein

   The reaction is carried out at 50 to 100 ° C for 0.5 to 3 hours.
6. The method of claim 4, wherein

   The compound of [Formula 4] is prepared by reacting (1-benzylaziridin-2-yl) methanol and chlorodimethyl (vinyl) silane at 40 to 80 ℃.
7. The method of claim 6,

   The (1-benzylaziridin-2-yl) methanol,

   Reacting ethyl 2,3-dibromopropanoate with benzylamine in the presence of a base such as nitrogen stream and triethylamine to produce ethyl 1-benzylaziridine-2-carboxylate; And

   And reacting the ethyl 1-benzylaziridine-2-carboxylate with lithium aluminum hydride.
8. The method of claim 4, wherein

   To 10 parts by weight of the compound represented by [Formula 2], 0.5 to 2 parts by weight of the compound represented by the above [Chemical Formula 3] and 0.02 to 0.2 parts by weight of the compound represented by the [Formula 4] characterized in that the reaction Manufacturing method.
9. The method of claim 4, wherein

   Reacting the compound represented by [Formula 1] with a compound containing a carboxylic acid, an alcohol, an amine group or a thiol group to ring-open the aziridine group of [Formula 1].

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