Rotaxane compounds

Abstract

To provide polyrotaxane that can be easily chemically modified for application to slide ring materials by making it easier to provide the polyrotaxane by finding a method capable of manufacturing the polyrotaxane by a more simple process compared with a conventional method.SOLUTION: To provide a method for producing polyrotaxane more easily without going through multiple steps as in conventional production methods, by using a pseudorotaxane containing an axial molecule and a cyclodextrin or cyclodextrin derivative having a triazinyl group as a cyclic molecule. According to the method of the present invention, the polyrotaxane can be readily provided by heating the pseudorotaxane or performing one-pot synthesis at room temperature by adding diamine. Furthermore, this polyrotaxane can be easily chemically modified by reacting with a chemical modifier.SELECTED DRAWING: None

Description

Technical Field

[0004] , ,

[0001] The present invention relates to rotaxane compounds. More specifically, the present invention relates to pseudo-rotaxanes and polyrotaxanes containing an axle molecule and a cyclodextrin or cyclodextrin derivative having a triazinyl group as a cyclic molecule, and methods for producing the same.

Background Art

[0002] Polyrotaxane is a supramolecule having a structure in which an axle molecule penetrates through the hollow part of a cyclic molecule such as cyclodextrin, and various research and developments have been carried out. There have also been developed cyclic polymer materials (slide-ring materials) in which this cyclic molecule crosslinks while having freedom and automatically relaxes stress and tension (see, for example, Non-Patent Document 1). A gel having this structure is called a slide-ring gel and exhibits high stretchability and toughness (see, for example, Non-Patent Document 2), and is used as a coating agent for golf balls or a cone for speakers for the purpose of strengthening polymers.

[0003] In addition, functionalized polyrotaxanes that are soluble in general-purpose organic solvents and can be used for forming various materials have been developed by attaching functional groups to the side chains of cyclic molecules. For example, Patent Document 1 discloses a modified polyrotaxane having modifying groups derived from two or more kinds of lactones, and it is described that it is useful for providing a solvent-based paint with improved solubility and suppressed aggregation. Further, Patent Document 2 discloses a sizing agent containing a polyrotaxane containing a cyclodextrin modified with a polymer chain and containing a specific bond or group as a cyclic molecule and a surfactant, and it is described that reinforcing fibers can be provided by applying this.

[0004] Although polyrotaxanes are highly useful in the production of various substances, their manufacture requires multiple steps, making it time-consuming and labor-intensive. Furthermore, the resulting polyrotaxanes are very expensive. Therefore, the inventors attempted to find a method for producing polyrotaxanes using a simpler process compared to conventional methods, thereby facilitating the provision of polyrotaxanes. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2011-178931 [Patent Document 2] Japanese Patent Publication No. 2017-48481 [Non-patent literature]

[0006] [Non-Patent Document 1] Yasushi Okumura and Kohzo Ito, The Polyrotaxane Gel: A Topological Gel by Figure-of-Eight Cross-links. Adv. Mater., 2001, 13:485-487. [Non-Patent Document 2] Kohzo Ito, Slide-ring materials using topological supramolecular architecture. Current Opinion in Solid State and Materials Science, 2010, 14:28-34. [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] The objective is to find a method for producing polyrotaxanes using a simpler process compared to conventional methods, thereby facilitating the provision of polyrotaxanes. Furthermore, another objective is to provide polyrotaxanes that are easily chemically modified for applications such as slide ring materials. [Means for solving the problem]

[0008] As a result of diligent research to solve the above problems, the inventors have developed a pseudorotaxane containing a axial molecule and a cyclodextrin (hereinafter sometimes simply referred to as CD) or a cyclodextrin derivative having a triazinyl group as a cyclic molecule. They have found that by using this pseudorotaxane, polyrotaxanes can be produced more easily without going through multiple steps as in conventional manufacturing methods. In the manufacturing method of the present invention, polyrotaxane-containing compositions such as slide ring materials can be easily produced by, for example, heating the pseudorotaxane or performing one-pot synthesis at room temperature by adding a diamine. Furthermore, by reacting this polyrotaxane with chemical modifiers, etc., polyrotaxanes with added functionality can be easily manufactured.

[0009] In other words, the present invention relates to pseudorotaxanes, polyrotaxanes, and methods for producing them as shown in (1) to (12) below. (1) A pseudorotaxane comprising a central molecule and a cyclodextrin or cyclodextrin derivative having a triazinyl group as a cyclic molecule. (2) The pseudorotaxane described in (1) above, wherein the axial molecule contains a polymer. (3) The pseudorotaxane according to (1) or (2) above, comprising a cyclodextrin or cyclodextrin derivative having a chemically modified triazinyl group as a cyclic molecule. (4) A polyrotaxane comprising an axial molecule and a cyclodextrin or cyclodextrin derivative having a triazinyl group as a cyclic molecule. (5) A method for producing a polyrotaxane according to (4) above, comprising the step of mixing a pseudorotaxane according to any of (1) to (3) above with a molecule that seals the axial molecule. (6) A method for producing the polyrotaxane according to (5) above, wherein the molecule that sequesters the axial molecule is 2-chloro-4,6-dimethoxy-1,3,5-triazine. (7) The polyrotaxane according to (4) above, comprising a cyclodextrin or cyclodextrin derivative having a chemically modified triazinyl group as a cyclic molecule. (8) A method for producing a chemically modified polyrotaxane as described in (7), comprising the step of reacting the polyrotaxane described in (4) above with a chemical modifier. (9) A method for producing the chemically modified polyrotaxane according to (8) above, wherein the chemical modifier is one or more diethylamine or 3-aminopropyltriethoxysilane. (10) A polyrotaxane-containing composition comprising one or more of the polyrotaxanes described in (4) or (7) above. (11) A method for producing the polyrotaxane-containing composition according to (10) above, comprising the step of mixing the pseudorotaxane described in any of (1) to (3) above with a diamine. (12) A method for producing the polyrotaxane-containing composition according to (10) above, comprising the step of heating the pseudorotaxane described in any of (1) to (3) above. [Effects of the Invention]

[0010] By using the axial molecule of the present invention and a pseudorotaxane containing a cyclodextrin or cyclodextrin derivative having a triazinyl group as a cyclic molecule, the production of polyrotaxanes and modified polyrotaxanes to which functionality has been imparted becomes easier. Furthermore, by using polyrotaxane-containing compositions that have various physical properties such as water absorption rate, elongation rate, and tensile strength, it becomes easier to manufacture products such as gels, resins, paints, rubbers, heat insulating materials, and shock absorbers that have excellent elasticity and durability. [Brief explanation of the drawing]

[0011] [Figure 1] This figure shows the measurement results of the UV spectra of chemically modified and unmodified polyrotaxanes (Example 3). [Figure 2] It is a figure showing the measurement results of 1H-NMR of APTES-added MCTCD polyrotaxane (Example 4). [Figure 3] A. It is a figure showing a photograph of a polyrotaxane-containing composition (slide ring gel) (Example 5). B. It is a figure schematically showing the network structure of a polyrotaxane-containing composition (slide ring gel) (Example 5). [Figure 4] It is a figure showing the water absorption rate of each polyrotaxane-containing composition (slide ring gel) (Example 5). [Figure 5] It is a figure showing an outline of the expansion and contraction test of each polyrotaxane-containing composition (slide ring gel) (Example 5). [Figure 6] It is a figure showing the elongation rate of each polyrotaxane-containing composition (slide ring gel) (Example 5). [Figure 7] It is a figure showing the elongation rate of each polyrotaxane-containing composition (slide ring gel) (Example 6).

Mode for Carrying Out the Invention

[0012] The "pseudorotaxane" of the present invention refers to a molecule having a rotaxane structure in which both ends of the axle molecule are not blocked, and includes an axle molecule and a cyclodextrin or cyclodextrin derivative having a triazinyl group as a cyclic molecule. This "pseudorotaxane" also includes a pseudorotaxane containing an axle molecule and a cyclodextrin or cyclodextrin derivative having a chemically modified triazinyl group as a cyclic molecule (that is, a chemically modified pseudorotaxane). Further, the "polyrotaxane" of the present invention refers to a molecule having a rotaxane structure in which both ends of the axle molecule are blocked, and includes an axle molecule and a cyclodextrin or cyclodextrin derivative having a triazinyl group as a cyclic molecule. This "polyrotaxane" also includes a polyrotaxane containing an axle molecule and a cyclodextrin or cyclodextrin derivative having a chemically modified triazinyl group as a cyclic molecule (that is, a chemically modified polyrotaxane).

[0013] The "axial molecules" contained in these "pseudorotaxanes" or "polyrotaxanes" can be any molecules capable of forming a structure in which the axial molecule penetrates the hollow part of a cyclic molecule, and can be in any shape, such as linear or branched. Furthermore, they can be commercially available or independently prepared. The "axis molecule" of the present invention preferably contains a polymer, and examples of polymers include polyethylene glycol, polyethylene, polyacetylene, polypropylene glycol, polyurethane, polystyrene, polydiene, polyyne, polysiloxane, polyamide, polyimide, polyetherketone, polycarbonate, and polythiophene. It may also be a copolymer composed of monomers of these polymers, or a copolymer containing these polymers. It may contain one or more of these polymers, or it may contain two or more. The polymers included in the "axis molecule" of the present invention include those having isocyanate groups, isothiocyanate groups, lactones, hydroxyl groups, carboxyl groups, amino groups, quaternary ammonium salts, epoxy groups, thiol groups, aldehyde groups, acryloyl groups, methacrylic groups, alkoxysilyl groups, or vinyl groups at their ends. Polyethylene glycol having amino groups at both ends is particularly preferred. This may be a commercially available product or one prepared in-house.

[0014] Furthermore, a "cyclic molecule" refers to a molecule having a cyclic structure, and any "cyclodextrin or cyclodextrin derivative having a triazinyl group" is acceptable, and this also includes "cyclodextrin or cyclodextrin derivative having a chemically modified triazinyl group." "Cyclodextrin or cyclodextrin derivative having a chemically modified triazinyl group" refers to a molecule in which some or all of the triazinyl group is chemically modified. Of these, "cyclodextrin having a triazinyl group" only needs to have one or more triazinyl groups, and can be of any type: α, β, γ, δ, or ε. Furthermore, "cyclodextrin derivatives having a triazinyl group" include, for example, methyl, ethyl, propyl, butyl, hydroxyethyl, hydroxypropyl, acetyl, benzoyl, sulfonyl, amino, tosyl, azide, glucosyl, maltosyl, t-butyldimethylsilyl, succinyl, carboxymethyl, carboxyethyl, glucuronylglucosyl, chloro, bromo, iodine, sulfopropyl, and other "cyclodextrin derivatives," as well as "cyclodextrin derivatives" that have undergone two or more of these chemical modifications and have one or more triazinyl groups. These cyclic molecules can be used individually or in combination of two or more. In particular, it is preferable to use monochlorotriazinyl-β-cyclodextrin (hereinafter sometimes simply referred to as MCTCD). These may be commercially available or prepared in-house.

[0015] Furthermore, a "molecule that seals the axial molecule" refers to a molecule that seals the axial molecule by binding to both ends of the axial molecule, thereby suppressing the detachment of the cyclic molecule. Any molecule that can produce a polyrotaxane having a structure in which the axial molecule penetrates the hollow part of the cyclic molecule by this "molecule that seals the axial molecule" may be used, and it may be a commercially available molecule or one that has been prepared in-house. Examples of "molecules that sequester the axial molecule" include 2-chloro-4,6-dimethoxy-1,3,5-triazine, adamantanes, cyclodextrins contained in MCTCD, compounds having a dinitrophenyl group, compounds having a trityl group, fluoresceins, pyrenes, steroids, silsesquioxanes, triazines, triazoles, or derivatives thereof. 2-chloro-4,6-dimethoxy-1,3,5-triazine is particularly preferred.

[0016] The present invention's "method for producing polyrotaxane" preferably includes a step of "mixing a pseudorotaxane with a molecule that sequesters the axial molecule." If the "pseudorotaxane" is a pseudorotaxane containing a "cyclodextrin or cyclodextrin derivative having a chemically modified triazinyl group" as a cyclic molecule (i.e., a chemically modified pseudorotaxane), then a "chemically modified polyrotaxane" can be produced by going through this step. Furthermore, in addition to these processes, "chemically modified polyrotaxanes" can also be produced by a manufacturing method that includes "a step of reacting polyrotaxanes with chemical modifiers." These manufacturing methods may further include other steps useful for producing the "polyrotaxane" or "chemically modified polyrotaxane" of the present invention.

[0017] The "chemical modifiers" that can be used in the manufacture of "chemically modified pseudo-rotaxanes" or "chemically modified polyrotaxanes" may be any conventionally known ones, and can be selected according to the purpose of the function to be imparted. Examples of such "chemical modifiers" include diethylamine, 3-aminopropyltriethoxysilane, diamine, isocyanate group, isothiocyanate group, lactone, hydroxyl group, carboxyl group, amino group, epoxy group, thiol group, aldehyde group, acryloyl group, methacrylic group, alkoxysilyl group, or vinyl group. One or more of these "chemical modifiers" may be used, or two or more may be used in combination.

[0018] The "polyrotaxane-containing composition" of the present invention refers to a composition containing one or more of the following: "a polyrotaxane comprising an axis molecule and a cyclodextrin or cyclodextrin derivative having a triazinyl group as a cyclic molecule" or "a polyrotaxane comprising an axis molecule and a chemically modified cyclodextrin or cyclodextrin derivative having a triazinyl group as a cyclic molecule." These compositions may also contain two or more of these polyrotaxanes in combination, and may consist only of polyrotaxanes or further contain other components. Examples of such "polyrotaxane-containing compositions" include compositions in which multiple polyrotaxanes are linked together, and compositions in which polyrotaxanes are linked to other polymers.

[0019] Such "polyrotaxane-containing compositions" include slide ring materials that are highly elastic, tough, and absorbent, as well as gel-like slide ring gels that possess these properties. Here, "stretchability" refers to the property of a polyrotaxane-containing composition that, after being deformed by applied stress, returns to its original shape after the stress is removed. For example, a polyrotaxane-containing composition of a certain length may return to its original length after being stretched by applying stress. This "elasticity" can be evaluated, for example, by calculating the ratio (elongation rate (%)) of the length just before breaking (i.e., the length at its maximum stretch) to the length before stretching a polyrotaxane-containing composition until it breaks. In this case, a higher elongation rate indicates greater elasticity.

[0020] Furthermore, "toughness" refers to a property that combines strength and flexibility. For example, it can be evaluated by examining the time and weight that a polyrotaxane-containing composition of a certain size and length can withstand without breaking when weights of 0.5 kg, 1.0 kg, or 1.5 kg are suspended from it. In this case, the longer the time it can withstand and the heavier the weight, the higher the toughness. Furthermore, "water absorption" refers to the property of a polyrotaxane-containing composition to absorb moisture such as water. For example, this can be evaluated by immersing the polyrotaxane-containing composition in water and stirring / shaking it for a certain period of time, and calculating the ratio of the weight of the polyrotaxane-containing composition after shaking to the weight of the polyrotaxane-containing composition before shaking (water absorption rate (%)). In this case, the higher the water absorption rate, the higher the water absorption.

[0021] The "polyrotaxane-containing composition" of the present invention is preferably manufactured using "a pseudorotaxane comprising an axial molecule and a cyclodextrin or cyclodextrin derivative having a triazinyl group as a cyclic molecule." One example of such a manufacturing method is one that includes a step of "mixing a pseudo-rotaxane with a diamine." The diamine used in this method may be any diamine capable of producing a "polyrotaxane-containing composition," and may be commercially available or independently prepared. Examples include ethylenediamine (hereinafter sometimes simply referred to as EDA), butanediamine (hereinafter sometimes simply referred to as BDA), hexanediamine (hereinafter sometimes simply referred to as HDA), octanediamine (hereinafter sometimes simply referred to as ODA), etc., and one or more of these may be used, or two or more in combination.

[0022] Furthermore, a manufacturing method that includes a step of heating a pseudo-rotaxane is also cited as a method for producing the "polyrotaxane-containing composition" of the present invention. "Heating" refers to applying heat to maintain the pseudo-rotaxane at a constant temperature, and this temperature can be any temperature at which the "polyrotaxane-containing composition" of the present invention can be manufactured. For example, the temperature may be "heated" to a temperature above 50°C, such as 55°C, 60°C, 70°C, 80°C, 90°C, or 100°C. These manufacturing methods may further include other steps useful for producing the "polyrotaxane-containing composition" of the present invention.

[0023] Furthermore, a "pseudorotaxane-containing composition" refers to a composition containing one or more of the following: "a pseudorotaxane containing a axial molecule and a cyclodextrin or cyclodextrin derivative having a triazinyl group as a cyclic molecule" or "a pseudorotaxane containing a axial molecule and a chemically modified cyclodextrin or cyclodextrin derivative having a triazinyl group as a cyclic molecule," and is not encapsulated by a "molecule that encapsulates the axial molecule." These pseudorotaxanes may be combined in combination of two or more types, and the composition may consist only of pseudorotaxanes or further contain other components. Examples of such "pseudorotaxane-containing compositions" include compositions in which multiple pseudorotaxanes are linked together, and compositions in which pseudorotaxanes are linked to other polymers.

[0024] The present invention will be described in detail below with reference to examples, but the present invention is not limited to those shown in the examples. [Examples]

[0025] The samples and test equipment used in the embodiments of the present invention are shown below. Unless otherwise specified, the same sample was used in the embodiments of the present invention. <Sample> 1. Polyethylene glycol (PEG, Ave. MW 20,000, Fujifilm Wako Pure Chemical Corporation) 2. Dry tetrahydrofuran (dry THF) Dry THF was prepared by drying high-performance liquid chromatography THF (Fujifilm Wako Pure Chemical Corporation) overnight in molecular sieves 3 Å (Fujifilm Wako Pure Chemical Corporation). 3.1,1'-Carbonyldiimidazole (CDI, Tokyo Chemical Industry Co., Ltd.) 4. Diamine 1) Ethylenediamine (EDA, Fujifilm Wako Pure Chemical Corporation) 2) Butanediamine (BDA, Tokyo Chemical Industry Co., Ltd.) 3) Hexanediamine (HDA, Fujifilm Wako Pure Chemical Corporation) 4) Octanediamine (ODA, Tokyo Chemical Industry Co., Ltd.)

[0026] 5. Cyclodextrin 1) Monoclotriazinyl-β-cyclodextrin (MCTCD, DS value 0.6, Cyclochem Bio Co., Ltd.) 2) Dihydroxytriazinyl-β-CD (DHT-CD) MCTCD was prepared by heating it to 80°C.

[0027] 6.2-Chloro-4,6-dimethoxy-1,3,5-triazine (DMT-Cl, Tokyo Chemical Industry Co., Ltd.) 7. Amine (1) Diethylamine (DEA, Fujifilm Wako Pure Chemical Corporation) (2) Triethylamine (TEA, Fujifilm Wako Pure Chemical Corporation) 8,3-aminopropyltriethoxysilane (APTES, Asahi Kasei Wacker Silicone Co., Ltd.) 9. Anhydrous ethanol (Fujifilm Wako Pure Chemical Industries, Ltd.) 10. Trifluoroacetic acid (TFA, Fujifilm Wako Pure Chemical Corporation)

[0028] <Testing equipment> 1. Centrifugal ultrafiltration filter: Amicon® Ultra (MWCO. 10kDa) (Merck KGaA) 2. Dialysis membrane: Spectra / Pore 7 dialysis membrane (MWCO. 1 kDa) (Funakoshi Co., Ltd.) 3. Thermogravimetric analyzer: TGA-1 (Shimadzu Corporation)

[0029] [Example 1] Method for producing pseudo-rotaxanes The pseudo-rotaxane was produced by the following steps 1 and 2. Step 1. -NH2 conversion of polyethylene glycol ends PEG, dried under reduced pressure in a desiccator, was dissolved in dry THF to a concentration of 12.5 mM. 4.4 times the amount of PEG in 1,1'-carbonyldiimidazole was added, and the mixture was stirred at 50°C for two days. Subsequently, 33 times the amount of PEG in ethylenediamine was added, and the mixture was stirred at 50°C for one day. The reaction course was observed by thin-layer chromatography (TLC) (eluent: CHCl3:MeOH=3:1, a few drops of triethylamine). After removing the solvent from the resulting reaction solution, it was dissolved in water and dialyzed for three days using a dialysis membrane (MWCO, 1 kDa). The mixture was freeze-dried to obtain PEG (PEG-BA) with -NH2 at both ends. This process is shown in Chemical Formula 1 below.

[0030] [ka]

[0031] Step 2. Production of pseudo-rotaxane The PEG-BA prepared in step 1 was dissolved in NaOH water to a concentration of 10 mM. Monochlorotriazinyl-β-cyclodextrin (MCTCD) was added in an amount 10, 20, 30, 40, or 50 times the amount of PEG-BA. The mixture was dissolved by sonication at room temperature (25±5℃), and then NaOH water was added again to bring the pH of the aqueous solution to 9 or higher. The solution was then left to stand overnight at 4℃ to prepare a pseudorotaxane aqueous solution. This process is shown in Chemical Formula 2 below.

[0032] [ka]

[0033] [Example 2] Polyrotaxane production Polyrotaxane was produced by the following process. Step 1. Using PEG-BA prepared in the same manner as in Example 1, pseudorotaxanes were prepared by adding 30 or 50 times the amount of MCTCD relative to the PEG-BA. Each of the resulting pseudorotaxane aqueous solutions was diluted with NaOH water to a PEG-BA concentration of 5 mM, and 40 times the amount of 2-chloro-4,6-dimethoxy-1,3,5-triazine (DMT-Cl) powder relative to the PEG-BA was added. The mixture was stirred overnight at room temperature (25±5℃). This process is shown in Chemical Formula 3 below.

[0034] [ka]

[0035] Step 2. Ethyl acetate was added to each reaction solution prepared in Step 1 to remove excess DMT-Cl. The aqueous layer was collected, and a portion of it was applied to Amicon® Ultra (MWCO, 10kDa). The filter was purified by repeated centrifugation (RT, 5,500 rpm) and addition of deionized water until no MCTCD remained in the lower layer of the filter. Subsequently, the aqueous solution in the upper layer of the filter was collected and freeze-dried to produce polyrotaxane.

[0036] Step 3. The polyrotaxane produced in Step 2 was subjected to a thermogravimetric analyzer, and the decrease in PEG chains and MCTCD in the polyrotaxane was calculated from the TG curve, and the amount of MCTCD inclusion per PEG chain molecule was determined. As a result, when 30 times the amount of MCTCD as PEG-BA was added, 3.5 times the amount of MCTCD was encapsulated per PEG chain molecule, and when 50 times the amount of MCTCD as PEG-BA was added, 10.6 times the amount of MCTCD was encapsulated per PEG chain molecule. Based on these results, the aqueous solution in the lower layer of the filter was also collected and weighed to estimate the total amount of MCTCD inclusions. The results showed that when a pseudo-rotaxane prepared by adding 30 times the amount of MCTCD to PEG-BA was used, 1.6 times the amount of MCTCD was inclusions per PEG chain molecule, and when a pseudo-rotaxane prepared by adding 50 times the amount of MCTCD was used, 11.4 times the amount of MCTCD was inclusions.

[0037] [Example 3] Production of chemically modified polyrotaxanes (1) Polyrotaxane and chemically modified polyrotaxane were produced by the following process. Step 1. Using PEG-BA prepared in the same manner as in Example 1, a pseudo-rotaxane was prepared by adding 50 times the amount of MCTCD relative to the PEG-BA. The resulting pseudo-rotaxane aqueous solution was diluted with NaOH water to a PEG-BA concentration of 5 mM, 40 times the amount of DMT-Cl powder relative to the PEG-BA was added, and the mixture was stirred overnight at room temperature (25±5℃).

[0038] Step 2. 20 mL of the polyrotaxane reaction solution obtained in Step 1 was diluted with 100 mL of deionized water, then 63 mL of diethylamine (DEA) was added, and the mixture was stirred at room temperature (25±5°C) for 3 days. This step is shown in Chemical Formula 4 below. The reaction course was confirmed by UV spectroscopy.

[0039] [ka]

[0040] Step 3. Ethyl acetate was added to the reaction solution obtained in Step 2 to remove excess DMT-Cl. The aqueous layer was recovered, and a portion of it was applied to Amicon® Ultra (MWCO, 10kDa). The filter was purified by repeated centrifugation (RT, 5,500 rpm) and addition of deionized water until no MCTCD-DEA or DEA remained in the lower layer. Subsequently, the aqueous solution in the upper layer of the filter was recovered and freeze-dried to produce a chemically modified polyrotaxane.

[0041] Step 4. The chemically modified polyrotaxane produced in Step 3 was subjected to TGA, and the inclusion amount of MCTCD per PEG chain molecule was determined using the same method as in Example 2, and the result was 5.3 times. Furthermore, after going through step 1, we also produced unmodified polyrotaxane by proceeding directly to step 3 without going through step 2.

[0042] The UV spectra of chemically modified polyrotaxanes and unmodified polyrotaxanes were measured, along with their combined CD concentrations. As a result, as shown in Figure 1, the unfunctionalized polyrotaxane (Figure 1, polyrotaxane) had a spectrum almost identical to that of dihydroxytriazinyl-β-CD (DHT-CD). On the other hand, the DEA-functionalized polyrotaxane (Figure 1, polyrotaxane + DEA) had a spectrum similar to that of the modification reaction (Figure 1, polyrotaxane + DEA reaction) after 3 days of stirring in step 2 (before purification). Furthermore, 1H-NMR measurements showed a peak derived from DEA at 1.1-1.2 ppm in the polyrotaxane chemically modified with DEA. Therefore, it was suggested that DEA modified the MCTCD encapsulating the PEG chain. Furthermore, it was confirmed that unmodified polyrotaxanes did not dissolve in heavy DMSO, while polyrotaxanes chemically modified with DEA ​​did dissolve in heavy DMSO. These results confirm that polyrotaxanes that can be easily chemically modified can be produced by using MCTCD as a cyclic molecule, and that polyrotaxanes with various physical properties can be produced.

[0043] [Example 4] Production of chemically modified polyrotaxanes (2) Polyrotaxane and chemically modified polyrotaxane were produced by the following process. Step 1. The polyrotaxane reaction solution prepared in Step 1 of Example 3 was washed with ethyl acetate to remove excess DMT-Cl. After confirming the presence of polyrotaxane and MCTCD not incorporated into the polyrotaxane in the aqueous layer by TLC (eluent: CHCl3:MeOH = 1:1), the aqueous layer was freeze-dried. The obtained powder was repeatedly suspended and filtered in MeOH:EtOH = 20:80 to extract only the polyrotaxane. 1.295 g of the obtained polyrotaxane powder was suspended in 60 mL of anhydrous ethanol, and 0.325 mL of 3-aminopropyltriethoxysilane and 0.195 mL of triethylamine were added. The mixture was stirred overnight at room temperature (25 ± 5 °C). This process is shown in Chemical Formula 5 below. The reaction course was confirmed by TLC (eluent: CHCl3:MeOH = 1:1) and UV spectroscopy.

[0044] [ka]

[0045] Step 2. The reaction solution from Step 1 was concentrated and then washed with anhydrous ethanol. The resulting precipitate was dried to obtain a white solid. 82 mg of this solid was dissolved in 2 mL of deuterated DMSO, and 50 μL of trifluoroacetic acid was added to prepare a sample for NMR. When this sample was subjected to 1H-NMR spectroscopy, peaks for the methylene group of the aminopropyl group (C: 0.85 ppm, D: 1.6 ppm (m)), and the methyl group (A: 1.0 ppm (t)) and methyl group (B: 3.4 ppm (q)) of the ethoxy group were observed, as shown in Figure 2. Therefore, these results confirm that APTES-added MCTCD polyrotaxane was successfully synthesized.

[0046] While silane coupling agents have conventionally been used in various fields such as adhesives, paints, and heat insulating materials, as well as in coating compositions applied to automotive paint surfaces and silica aerogels, they have suffered from brittleness due to the siloxane bond. On the other hand, the cyclic molecule of the present invention to which a silane coupling agent is bonded, and the chemically modified polyrotaxane (APTES-added MCTCD polyrotaxane), exhibits high durability and can be used to provide more useful organic-inorganic hybrid materials.

[0047] [Example 5] Production of polyrotaxane-containing compositions (1) A polyrotaxane-containing composition was produced by the following process. Step 1. Using PEG-BA prepared in the same manner as in Example 1, the PEG-BA was dissolved in NaOH water to a concentration of 10 mM, 30 or 50 times the amount of MCTCD as PEG-BA was added, and the mixture was dissolved by ultrasonic irradiation with RT. The mixture was then allowed to stand overnight at 4°C to produce a pseudo-rotaxane. Step 2. Dilute the pseudo-rotaxane prepared in Step 1 with NaOH water so that the PEG-BA concentration is 5 mM or 7 mM. Take 4 mL of each into a measuring cup, add four types of diamine in the proportions shown in Table 1, and pour into a container made by securing both ends of a straw (6 mm in diameter, approximately 15 cm in length) with vinyl tape and a rubber band. Allow to stand at room temperature (25 ± 5 °C) for 3 days to prepare a polyrotaxane-containing composition.

[0048] As a result, as shown in Figure 3A, gelation occurred in all formulations, confirming that polyrotaxane-containing compositions (slide ring gels) can be produced in water at room temperature (25±5℃) by one-pot synthesis. Furthermore, gelation did not occur when diamine was added to the mixture of PEG-BA and MCTCD, i.e., before the pseudo-rotaxane was formed. Similarly, gelation did not occur when using PEG or PEG-COOH with unmodified ends. Therefore, these results suggest that the addition of diamine shortens the distance between pseudorotaxanes, and the -NH2 at the PEG terminus reacts with the MTC group of MCTCD that penetrates the PEG chain, capping both ends of the pseudorotaxane and forming a network structure as shown in Figure 3B.

[0049] [Material property evaluation] The physical properties (water absorption rate, elongation rate, and tensile strength) of the polyrotaxane-containing composition (slide ring gel) produced as described above were evaluated. 1. Water absorption test After measuring the weight of each polyrotaxane-containing composition removed from its container, the composition was immersed in 15 mL of water and stirred and shaken at 55 rpm for 3 days at 25°C. The weight of each polyrotaxane-containing composition was then measured. The water absorption rate was calculated using the following formula, and the results are shown in Figure 4.

[0050]

number

[0051] 2. Stretch Test Each polyrotaxane-containing composition was removed from its container, its length was standardized to 5 cm, and it was stretched to the point where it would not break, after which it was confirmed to return to its original length. Subsequently, as shown in Figure 5, each polyrotaxane-containing composition was stretched until it broke. The growth rate was calculated using the following formula, and the results are shown in Figure 6.

[0052]

number

[0053] 3. Tensile Test Each polyrotaxane-containing composition was standardized to a diameter of 6 mm and a length of 3.8 cm. One to three PET bottles filled with water (adjusted to 500 g) were hung from the compositions to verify the time they could withstand the load (0.5 kg, 1.0 kg, or 1.5 kg). Table 1 shows the weight and duration of each polyrotaxane composition as its tensile strength.

[0054] [Table 1]

[0055] As shown in Table 1, it was confirmed that polyrotaxane-containing compositions (slide ring gels) with various properties can be produced by changing the PEG-BA concentration, the amount of MCTCD added, and the carbon chain length and concentration of the diamine used as a crosslinking agent when producing pseudorotaxanes. Furthermore, it was confirmed that by adjusting the PEG-BA concentration and the amount of MCTCD added, a tough slide ring gel that can withstand a 1.0 kg weight for more than 60 seconds without breaking can be produced regardless of the diamine used. Furthermore, even when using polyrotaxane-containing compositions of different lengths than those used in the above tests, the tolerable time and weight remained almost the same, suggesting that the durability of the polyrotaxane-containing composition does not depend on the length of the gel.

[0056] [Example 6] Production of polyrotaxane-containing compositions (2) A polyrotaxane-containing composition was produced by the following process. Step 1. Using PEG-BA prepared in the same manner as in Example 1, the PEG-BA was dissolved in NaOH water to a concentration of 10 mM, 50 molar equivalents of MCTCD were added to the PEG-BA, dissolved by ultrasonic irradiation with RT, and allowed to stand overnight at 4°C to produce a pseudo-rotaxane. Step 2. The pseudo-rotaxane prepared in Step 1 was heated for approximately 6 hours, then left to stand at room temperature for 18 hours to produce a slide ring gel as a polyrotaxane-containing composition.

[0057] When heated at 60°C, an extremely viscous slide ring gel was obtained. Furthermore, when heated at 70°C, a slide ring gel with lower viscosity and superior toughness compared to the gel produced at 60°C was obtained. Furthermore, it was confirmed that a slide ring gel could also be obtained by adding 40 molar equivalents of MCTCD to PEG-BA in the same process as described above, heating the resulting pseudo-rotaxane at 60°C for approximately 6 hours, and then allowing it to stand at room temperature for 64 hours. The elongation of each slide ring gel was investigated using the same method as in the stretch test of Example 5, and the results are shown in Figure 7. As a result, it was confirmed that slide ring gels exhibiting various physical properties as polyrotaxane-containing compounds can be obtained by adjusting the heating temperature, standing time at room temperature, etc. [Industrial applicability]

[0058] By using the axial molecule of the present invention and a pseudorotaxane containing a cyclodextrin or cyclodextrin derivative having a triazinyl group as a cyclic molecule, the production of polyrotaxanes and modified polyrotaxanes to which functionality has been imparted becomes easier. Furthermore, by using polyrotaxane-containing compositions that have various physical properties such as water absorption rate, elongation rate, and tensile strength, it becomes easier to manufacture products such as gels, paints, resins, rubbers, heat insulating materials, and shock absorbers that have excellent elasticity and durability.

Claims

1. A pseudorotaxane comprising a central molecule and a cyclodextrin or cyclodextrin derivative having a monochlorotriazinyl group as a cyclic molecule.

2. The pseudorotaxane according to claim 1, wherein the axial molecule contains a polymer.

3. The pseudorotaxane according to claim 1, comprising a cyclodextrin or cyclodextrin derivative having a chemically modified triazinyl group as a cyclic molecule.

4. A polyrotaxane comprising an axial molecule and a cyclodextrin or cyclodextrin derivative having a monochlorotriazinyl group as a cyclic molecule.

5. A method for producing a polyrotaxane according to claim 4, comprising the step of mixing a pseudorotaxane according to any one of claims 1 to 3 with a molecule that seals the axial molecule.

6. A method for producing a polyrotaxane according to claim 5, wherein the molecule that sequesters the axial molecule is 2-chloro-4,6-dimethoxy-1,3,5-triazine.

7. The polyrotaxane according to claim 4, comprising a cyclodextrin or cyclodextrin derivative having a chemically modified monochlorotriazinyl group as a cyclic molecule.

8. A method for producing a chemically modified polyrotaxane according to claim 7, comprising the step of reacting the polyrotaxane according to claim 4 with a chemical modifier.

9. A method for producing a chemically modified polyrotaxane according to claim 8, wherein the chemical modifier is one or more diethylamine or 3-aminopropyltriethoxysilane.

10. A polyrotaxane-containing composition comprising one or more polyrotaxanes as described in claim 4 or 7.

11. A method for producing a polyrotaxane-containing composition according to claim 10, comprising the step of mixing a pseudorotaxane and a diamine according to any one of claims 1 to 3.

12. A method for producing a polyrotaxane-containing composition according to claim 10, comprising the step of heating a pseudorotaxane according to any one of claims 1 to 3.

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