Method for producing polymer and polymer

Abstract

To provide a polymer production method that is suitable for producing a (meth)acrylamide polymer or a (meth)acrylate polymer possessing stereoregularity.SOLUTION: A production method provided herein includes polymerizing a monomer a of formula (1) to form a polymer A, and converting the polymer A into a polymer B by an alcohol substitution reaction or an amine substitution reaction. R1 is a hydrogen atom or a methyl group, and R2 is an alkyl group that may have a substituent, an aryl group that may have a substituent, or a hydrogen atom.SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present invention relates to a method for producing a polymer and the polymer. [Background technology]

[0002] The stereoregularity (tacticity) of a vinyl polymer is known to affect its physical properties, such as crystallinity and glass transition temperature. For example, polypropylene (PP) is widely used as a crystalline polymer material, but atactic PP, which lacks stereoregularity, does not exhibit crystallinity and cannot be used as a bulk molding material. It has been common knowledge among those skilled in the art that the production of stereoregular polymers requires the selection and design of specific catalysts and additives depending on the type of polymer and polymerization method. For example, Patent Document 1 discloses a method for producing polar vinyl polymers with a heterotactic triad content of less than 35% by proceeding with living radical polymerization in the presence of a copper complex catalyst. Patent Document 2 discloses a method for producing fluorine-containing polymers with an isotacticity of 65% or more by proceeding with anionic polymerization in the presence of an organolithium compound. [Prior art documents] [Non-patent literature]

[0003] [Patent Document 1] Patent Publication No. 2021-46484 [Patent Document 2] Patent No. 6013055 Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention provides a method for producing a polymer that is suitable for producing a stereoregular (meth)acrylamide polymer or a stereoregular (meth)acrylate polymer. [Means for solving the problem]

[0005] [1] A method for producing a polymer according to an embodiment of the present invention includes: polymerizing a monomer a represented by the following formula (1) to form a polymer A; and converting the polymer A into a polymer B that is different from the polymer A by an alcohol substitution reaction or an amine substitution reaction. [ka] R in the formula (1) 1 is a hydrogen atom or a methyl group. 2 represents an alkyl group which may have a substituent, an aryl group which may have a substituent, or a hydrogen atom. [2] In the method for producing a polymer according to the above [1], 2 may be an aliphatic alkyl group having 1 to 6 carbon atoms which may have a substituent, or a phenyl group which may have a substituent. [3] In the method for producing a polymer according to the above [1] or [2], 2 may be a phenyl group which may have a substituent. [4] In the method for producing a polymer according to any one of the above [1] to [3], the polymer A may be formed by radically polymerizing the monomer a. [5] In the method for producing a polymer according to any one of the above [1] to [4], the polymerization of the monomer a may be carried out at 30° C. or lower. [6] In the method for producing a polymer according to any one of the above items [1] to [5], the polymer B may be isotactic. [7] In the method for producing a polymer according to the above item [6], the isotacticity of the polymer B may be 95% or more. [8] In the method for producing a polymer according to any one of the above [1] to [7], the polymer B may be a (meth)acrylate polymer or a (meth)acrylamide polymer. [9] In the method for producing a polymer according to any one of the above items [1] to [8], the polymer B may be composed of a structural unit represented by the following formula (3): [ka] R in the formula (3) 1 is a hydrogen atom or a methyl group. 3 and R 4 are each independently a hydrogen atom, an optionally substituted alkyl group, an optionally substituted alkylamino group, an optionally substituted allyl group, an optionally substituted alkyl ether group, an optionally substituted hydroxyalkyl group, an optionally substituted carboxy group, or an optionally substituted ester group. 3 and R 4 may be connected to each other.

[10] A polymer according to an embodiment of the present invention comprises: It is an isotactic polymer (polymer B) composed of structural units shown in the following formula (3). [ka] R in the formula (3) 1 is a hydrogen atom or a methyl group. 3 and R 4 are each independently a hydrogen atom, an optionally substituted alkyl group, an optionally substituted alkylamino group, an optionally substituted allyl group, an optionally substituted alkyl ether group, an optionally substituted hydroxyalkyl group, an optionally substituted carboxy group, or an optionally substituted ester group. 3 and R 4 may be connected to each other.

[11] In the polymer according to the above

[10] , the isotacticity of the polymer may be 95% or more.

[12] A method for producing a polymer according to another embodiment of the present invention includes the steps of: The method includes polymerizing a monomer a shown in the following formula (1) to form an isotactic polymer A. [ka] R in the formula (1) 1is a hydrogen atom or a methyl group. 2 represents an alkyl group which may have a substituent, an aryl group which may have a substituent, or a hydrogen atom.

[13] In the method for producing a polymer according to the above item

[12] , the polymer A may have an isotacticity of 95% or more.

[14] Another embodiment of the present invention provides a polymer: It is an isotactic polymer (polymer A) composed of structural units shown in the following formula (2). [ka] R in the formula (2) 1 is a hydrogen atom or a methyl group. 2 represents an alkyl group which may have a substituent, an aryl group which may have a substituent, or a hydrogen atom.

[15] In the polymer according to the above

[14] , the isotacticity of the polymer may be 95% or more. [Effects of the Invention]

[0006] According to the present invention, there is provided a method for producing a polymer suitable for producing a stereoregular (meth)acrylamide polymer or a stereoregular (meth)acrylate polymer. [Brief explanation of the drawings]

[0007] [Figure 1] 1 shows the H-NMR spectrum and the C-NMR spectrum of the precursor of Monomer a prepared in Synthesis Example 1. [Figure 2] 1 shows the H-NMR spectrum and the C-NMR spectrum of Monomer a prepared in Synthesis Example 2. [Figure 3] 1H-NMR spectrum of the methyl acrylate polymer (PMA) prepared in Example 4. [Figure 4A] 1 is a 13C-NMR spectrum of PMA prepared in Example 4. [Figure 4B] FIG. 4B is an enlarged view of the dashed line portion of the spectrum in FIG. 4A. [Figure 5] 1 is a 1H-NMR spectrum of n-butyl acrylate (PBA) prepared in Example 5. [Figure 6] 1H-NMR spectrum of the acrylamide polymer prepared in Example 6. [Figure 7] 1H-NMR spectra of the acrylamide polymer produced in Example 6 and an atactic acrylamide polymer prepared separately. [Figure 8] 1H-NMR spectrum of the acrylamide polymer prepared in Example 6. [Figure 9] 1H-NMR spectrum of the acrylamide polymer prepared in Example 7. [Figure 10] 1H-NMR spectra of the acrylamide polymer produced in Example 8 and an atactic acrylamide polymer prepared separately. [Figure 11] 1 shows DSC curves of the acrylamide polymer produced in Example 10 and an atactic acrylamide polymer prepared separately. [Figure 12A] 1 shows DSC curves of the acrylamide polymer produced in Example 10 and an atactic acrylamide polymer prepared separately. [Figure 12B] 1 shows DSC curves of the acrylamide polymer produced in Example 10 and an atactic acrylamide polymer prepared separately. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments.

[0009] In this specification, (meth)acrylic means acrylic or methacrylic, and (meth)acrylate means acrylate or methacrylate.

[0010] <<First embodiment: Method for producing polymer B>> The method for producing a polymer according to the first embodiment of the present invention includes polymerizing a monomer a shown in the following formula (1) to form a polymer A, and converting the polymer A into a polymer B different from the polymer A by an alcohol substitution reaction or an amine substitution reaction. 1 is a hydrogen atom or a methyl group. 2 is an alkyl group which may have a substituent, an aryl group which may have a substituent, or a hydrogen atom. Hereinafter, the reaction of polymerizing monomer a to form polymer A will be referred to as a "polymerization reaction," and the reaction of converting polymer A into polymer B by an alcohol substitution reaction or an amine substitution reaction will be referred to as a "conversion reaction." [ka]

[0011] <Polymerization reaction> In the polymerization of monomer a, addition polymerization of the vinyl group possessed by monomer a usually proceeds. Polymer A formed from monomer a is a vinyl polymer and usually comprises the structural unit shown in the following formula (2). R possessed by the structural unit of formula (2) 1 and R 2 Examples of R that the monomer a in formula (1) may have are: 1 and R 2 The same as the example of R of polymer A. 1 and R 2 are the R of the monomer a used in the polymerization, respectively. 1 and R 2 is the same as [ka]

[0012] Monomer a has a bulky side chain structure with a specific ring structure. It is thought that this bulky side chain structure may contribute to the stereoregularity of polymer A formed by the polymerization of monomer a. The main chain structure may be twisted to avoid the repulsion of this bulky structure, forming a helical structure and isotactically controlled. In addition, the carbonyl bond in the amide bond close to the main chain of polymer A is activated by the electron-withdrawing groups of the carbonyl and sulfonyl groups adjacent to the nitrogen, which is thought to make it easier for substitution reactions with amines (amine substitution reactions) to occur.

[0013] The isotacticity of the polymer A is, for example, 70% or more, and may be 73% or more, 75% or more, 78% or more, 80% or more, 81% or more, 82% or more, 83% or more, 84% or more, 85% or more, 86% or more, 87% or more, 88% or more, 89% or more, 90% or more, 91% or more, 92% or more, 93% or more, 94% or more, 95% or more, 96% or more, 97% or more, 98% or more, or even 99% or more. The upper limit of the isotacticity of the polymer A is 100% or less, and may be 99.5% or less.

[0014] The isotacticity of a polymer can be determined by the ratio of meso-dyads to the total dyads of the polymer. For example, 1 The area of ​​the peak originating from the meso-dyad on the H-nuclear magnetic resonance (NMR) spectrum is S m , the area of ​​the peak originating from the racemo dyad is S r When this is done, the formula is: Isotacticity = S m / (S m +S r ) can be used to identify the peaks derived from meso- and racemo-dyads. The peaks derived from the hydrogen atoms bonded to the β-carbon atom in the -CC- structure formed by the polymerization of vinyl groups can be selected. Note that the peaks derived from meso-dyads are usually observed as sharper peaks with smaller half-widths as the isotacticity of the polymer increases.

[0015] R 2The alkyl group may be linear, branched, or cyclic. The alkyl group may be an aliphatic alkyl group or an aromatic alkyl group. The number of carbon atoms in the alkyl group is, for example, 1 to 20, and may be 1 to 15, 1 to 12, 1 to 10, 1 to 8, 1 to 7, 1 to 6, 1 to 5, 1 to 4, or even 1 to 3. The alkyl group may have a substituent. Examples of the substituent include hydrocarbon groups such as alkyl groups and phenyl groups, carboxy groups, acyl groups, alkoxy groups, hydroxy groups, ester groups, cyano groups, nitro groups, sulfonyl groups, and halogen groups. The substituent may be a long-chain alkyl group having 12 or more carbon atoms, or a long-chain alkoxy group having 12 or more carbon atoms. Note that R 2 The examples of the substituents that each group exemplified in this specification may have are not limited to the substituents that the alkyl group may have, but are the same as the examples above.

[0016] R 2 The alkyl group that can be R may be an alkyl group having 1 to 6 carbon atoms which may have a substituent, a linear or branched aliphatic alkyl group having 1 to 6 carbon atoms, a linear or branched aliphatic alkyl group having 1 to 4 carbon atoms, or a linear or branched aliphatic alkyl group having 1 to 3 carbon atoms. 2 The alkyl group may be a methyl group, an ethyl group, an n-propyl group, an isopropyl group, or an n-butyl group.

[0017] R 2 Examples of the aryl group that can be (a) include a phenyl group, a tolyl group, a xylyl group, a naphthyl group, a cumenyl group, and a mesityl group, and may be a phenyl group. The aryl group may have a substituent, or may be a phenyl group that may have a substituent. The aryl group refers to a functional group derived from an aromatic hydrocarbon.

[0018] R 2 may be an aliphatic alkyl group having 1 to 6 carbon atoms which may have a substituent, or a phenyl group which may have a substituent. 2R may be a phenyl group which may have a substituent, or may be a phenyl group. 2 When R is an optionally substituted phenyl group, particularly a phenyl group, this can contribute to improving the isotacticity of polymer A. 2 is a phenyl group which may have a substituent, particularly a phenyl group, which can contribute to improving the solubility of monomer a in the polymerization system when monomer a is polymerized by solution polymerization. Depending on the degree of improvement in solubility, it may also be possible to consider the formation of polymer A by living polymerization. From the viewpoint of improving solubility, the substituent on the phenyl group is preferably a long-chain alkyl group or a long-chain alkoxy group.

[0019] The polymerization of the monomer a is typically carried out by radical polymerization. In other words, the polymer A may be formed by radical polymerization of the monomer a. The radical polymerization may be living radical polymerization. The polymerization method may be, for example, solution polymerization, emulsion polymerization, or suspension polymerization, and is preferably solution polymerization.

[0020] A solvent capable of dissolving monomer a can be selected for the solution polymerization. Examples of the solvent include aromatic hydrocarbons such as toluene and benzene, aliphatic hydrocarbons such as n-hexane, cyclohexane, methylcyclohexane, and n-heptane, halogen-containing hydrocarbons such as dichloroethane and chlorobenzene, ketones such as methyl ethyl ketone and methyl isobutyl ketone, esters such as ethyl acetate, ethers such as 1,4-dioxane, and nitriles such as acetonitrile. However, the solvent is not limited to the above examples as long as it dissolves monomer a. The solvent may be a mixed solvent of two or more solvents. The solvent is usually a nonaqueous solvent. A dehydrating agent such as molecular sieves may be used to remove as much water as possible from the solvent.

[0021] The polymerization of the monomer a is preferably carried out in an atmosphere of an inert gas such as nitrogen or argon.

[0022] The polymerization system may contain an additive for controlling polymerization. An example of the additive is a polymerization initiator. In addition to the polymerization initiator, a chain transfer agent may also be contained.

[0023] Examples of the polymerization initiator include an azo-based polymerization initiator and a peroxide-based polymerization initiator. An example of the azo-based polymerization initiator is 2,2'-azobisisobutyronitrile (AIBN). An example of the peroxide-based polymerization initiator is benzoyl peroxide (BPO). However, the polymerization initiator is not limited to the above examples. The amount of the polymerization initiator used is, for example, 0.1 to 10 molar equivalents, and may be 0.5 to 5.0 molar equivalents, relative to 100 molar equivalents of the monomer a.

[0024] Examples of the chain transfer agent include sulfur-containing compounds such as thiol and thioester, and halides. However, the chain transfer agent is not limited to the above examples. The amount of the chain transfer agent used is, for example, 1 to 50 molar equivalents relative to the total amount (molar equivalents) of the polymerization initiator. By using the chain transfer agent, for example, the molecular weight of the polymer A can be controlled.

[0025] The polymerization system may be substantially free of additives other than the polymerization initiator. In the method for producing a polymer according to the first embodiment, an isotactic polymer A can be formed even in a polymerization system substantially free of additives other than the polymerization initiator. "Substantially free" means that the content relative to 100 molar equivalents of monomer a is less than 0.1 molar equivalents, preferably 0.05 molar equivalents or less, and more preferably 0.01 molar equivalents or less. Although there have been reports of controlling stereoregularity by selecting a specific polymerization mode and polymerization conditions, catalyst, and additives appropriate for the polymer to be formed, it has been common technical knowledge among those skilled in the art that it is difficult to control stereoregularity in radical polymerization or cationic polymerization. The fact that an isotactic polymer A (and polymer B after conversion) can be formed even in a polymerization system substantially free of additives other than the polymerization initiator is advantageous and useful in that it goes beyond conventional common technical knowledge.

[0026] The polymerization temperature of monomer a is, for example, −60 to 80° C. The upper limit of the polymerization temperature may be 70° C. or lower, 60° C. or lower, 50° C. or lower, 40° C. or lower, 30° C. or lower, 20° C. or lower, 10° C. or lower, 0° C. or lower, −10° C. or lower, −20° C. or lower, or even −30° C. or lower. The lower limit of the polymerization temperature may be −50° C. or higher, −45° C. or higher, or even −40° C. or higher. The polymerization of monomer a may be allowed to proceed at 30° C. or lower, 20° C. or lower, 10° C. or lower, 0° C. or lower, or even −10° C. or lower. According to studies by the present inventors, lowering the polymerization temperature can contribute to increasing the isotacticity of polymer A to be formed and polymer B converted from polymer A.

[0027] The polymerization time of the monomer a is, for example, 1 to 100 hours, and may be 5 to 75 hours, or even 10 to 50 hours. The polymerization of the monomer a may be carried out under normal pressure.

[0028] In the polymerization of the monomer a, the polymerization system may be irradiated with ultraviolet light. The irradiation of ultraviolet light can contribute to the promotion of polymerization, particularly when the polymerization temperature is low, for example, 20°C or lower, 0°C or lower, or even -10°C or lower.

[0029] <Conversion reaction> In the conversion reaction, polymer A formed by polymerization of monomer a is converted to polymer B by an alcohol substitution reaction or an amine substitution reaction. The converted polymer B typically has the same stereoregularity as polymer A. In other words, the converted polymer B may be isotactic. The method for producing a polymer according to the first embodiment is suitable for forming an isotactic polymer B. The isotacticity of polymer B is, for example, 70% or more, and may be 73% or more, 75% or more, 78% or more, 80% or more, 81% or more, 82% or more, 83% or more, 84% or more, 85% or more, 86% or more, 87% or more, 88% or more, 89% or more, 90% or more, 91% or more, 92% or more, 93% or more, 94% or more, 95% or more, 96% or more, 97% or more, 98% or more, or even 99% or more. The upper limit of the isotacticity of polymer B is 100% or less, and may be 99.5% or less.

[0030] The present inventors have found for the first time that the side chain of polymer A has higher activity in alcohol substitution reactions and amine substitution reactions than the side chain of monomer a.

[0031] Polymer A is usually composed of structural units shown in the following formula (2). When polymer A undergoes an alcohol substitution reaction, the chemical structure shown in the following formula (4) is usually eliminated at the wavy line in said formula and substituted with an organic group derived from alcohol, thereby converting polymer A into polymer B, which is a (meth)acrylate polymer. In the above conversion, only a portion of the side chains of the polymer are substituted, and therefore the stereoregularity of polymer A is maintained in polymer B after conversion. [ka] [ka]

[0032] Furthermore, when polymer A is subjected to an amine substitution reaction, the chemical structure shown in formula (4) is usually eliminated from the structural unit of formula (2) and substituted with an amine group, thereby converting polymer A into a (meth)acrylamide polymer, polymer B. As in the alcohol substitution reaction, the stereoregularity of polymer A is maintained in polymer B after conversion.

[0033] The polymer B formed by the method for producing a polymer according to the first embodiment may be a (meth)acrylate polymer or a (meth)acrylamide polymer. These polymers may be isotactic.

[0034] Examples of the polymer B that is a (meth)acrylate polymer include chain alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, and n-butyl (meth)acrylate; and cyclic alkyl (meth)acrylates such as cyclobutyl (meth)acrylate, cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, cyclopentyl (meth)acrylate, and cyclooctyl (meth)acrylate. However, the (meth)acrylate polymer polymer B is not limited to the above examples.

[0035] The polymer B after the conversion, in other words, the polymer B formed by the method for producing a polymer according to the first embodiment, may be a polymer composed of structural units represented by the following formula (3). Such a polymer is included in the category of (meth)acrylamide polymers. [ka] R in Equation (3) 1 is a hydrogen atom or a methyl group. 3 and R 4 are each independently a hydrogen atom, an optionally substituted alkyl group, an optionally substituted alkylamino group, an optionally substituted allyl group, an optionally substituted alkyl ether group, an optionally substituted hydroxyalkyl group, an optionally substituted carboxy group, or an optionally substituted ester group. 3 and R 4 R may be the same or different from each other. 3 and R 4 may be connected to each other. 3 and R 4 At least one selected from the group consisting of may be a hydrogen atom, or only one selected from the above group may be a hydrogen atom.

[0036] R 3 ,R 4The alkyl group may be linear, branched, or cyclic. The alkyl group may be an aliphatic alkyl group or an aromatic alkyl group. The number of carbon atoms in the alkyl group may be, for example, 1 to 20, 1 to 18, 1 to 15, 1 to 13, 1 to 10, 1 to 9, or even 1 to 8. The alkyl group may have a substituent. Examples of the aliphatic alkyl group are a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, and a 2-ethylhexyl group. Examples of the cyclic alkyl group are a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the aromatic alkyl group are a benzyl group, a 1-naphthylmethyl group, and a 4-ethylimidazole group. However, R 3 ,R 4 The alkyl groups that can be are not limited to the above examples.

[0037] Examples of alkylamino groups include groups in which an amino group is bonded to the terminal of the alkyl chain of the above-mentioned aliphatic alkyl group or to a carbon atom constituting the ring, but the alkylamino group is not limited to the above examples.

[0038] Examples of alkyl ether groups include groups in which an ether group is inserted between carbon atoms constituting the alkyl chain or between carbon atoms constituting the ring of the above-mentioned aliphatic alkyl group, but the alkyl ether group is not limited to the above examples.

[0039] Examples of hydroxyalkyl groups include groups in which a hydroxy group is bonded to the terminal of the above-mentioned aliphatic alkyl group or to a carbon atom constituting a ring, but the hydroxyalkyl group is not limited to the above examples.

[0040] R connected to each other 3 ,R 4 is R 3 and R 4 may form a ring structure together with the nitrogen atom to which it is attached. An example of such a ring structure is a morpholine structure.

[0041] Examples of polymer B which is a (meth)acrylamide polymer include N-methyl(meth)acrylamide, N-ethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N-(n-butyl)(meth)acrylamide, N-(n-hexyl)(meth)acrylamide, N-(n-octyl)(meth)acrylamide, N-(2-ethylhexyl)(meth)acrylamide, N-cyclobutyl(meth)acrylamide, N-cyclopentyl(meth)acrylamide, N-cyclohexyl(meth)acrylamide, N-cyclopentyl(meth)acrylamide, N-cyclooct ... The polymer B may be a polymer of each of the (meth)acrylamides, such as N-methyl(meth)acrylamide, N-benzyl(meth)acrylamide, N-naphthylmethyl(meth)acrylamide, N-(N,N-dimethylethyl)(meth)acrylamide, N-allyl(meth)acrylamide, N-(2-hydroxyethyl)(meth)acrylamide, N-[(2-methoxy)ethyl](meth)acrylamide, N-(ethylimidazole)(meth)acrylamide, N,N-diethyl(meth)acrylamide, N,N-di(n-butyl)(meth)acrylamide, and 4-(meth)acryloylmorpholine. The polymer B may also be a polymer of each of the acrylamides. However, the polymer B, which is a (meth)acrylamide polymer, is not limited to the above examples.

[0042] The alcohol substitution reaction may be carried out by, for example, adding an alcohol to a solution in which the polymer A is dissolved. The alcohol used in the alcohol substitution reaction is represented by the formula: R 5 R may be a compound represented by OH. 5 is, for example, a chain alkyl group such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, or an n-butyl group; or a cyclic alkyl group such as a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, or a cyclooctyl group. The alcohol preferably has solubility in a solution in which the polymer A is dissolved. Two or more types of alcohol may be used.

[0043] The amount of alcohol added is, for example, 1 to 20 mol, or may be 1 to 5 mol, per 1 mol of the structural units contained in the polymer A.

[0044] The amine substitution reaction may be carried out by, for example, adding an amine to a solution in which the polymer A is dissolved. The amine used in the amine substitution reaction is an amine represented by the formula: R 3 (R 4 )NH. 3 and R 4 Examples of R in Eq. (3) are 3 and R 4 The same as the example shown in the above. 3 and R 4 However, usually, R in the (meth)acrylamide polymer after conversion 3 and R 4 The amine preferably has solubility in the solution in which the polymer A is dissolved. Two or more types of amines may be used.

[0045] The amount of the amine added is, for example, 1 to 20 mol, or may be 1 to 3 mol, per 1 mol of the structural units that the polymer A has.

[0046] In the polymer production method according to the first embodiment, by changing the amine used in the amine substitution reaction, it is possible to form various (meth)acrylamide polymers from the same polymer A; in other words, it is possible to synthesize a library of (meth)acrylamide polymers. Furthermore, all of the various (meth)acrylamide polymers that can be formed can be isotactic. Conventionally, the formation of isotactic polymers required optimization of the polymerization mode and polymerization conditions for each polymer, and optimization was often difficult. At least in this respect, there were significant limitations on the synthesis of libraries of isotactic polymers. In the polymer production method according to the first embodiment, the polymerization itself involves only the formation of polymer A from monomer a, and therefore optimization of the polymerization mode and polymerization conditions for each (meth)acrylamide polymer is not necessary. In this respect, the production method is advantageous and useful.

[0047] Examples of the solvent contained in the solution in which polymer A is dissolved are the same as the examples of the solvent that can be contained in the polymerization solution from which polymer A is formed. The solvent contained in the solution in which polymer A is dissolved may be the same as the solvent contained in the polymerization solution from which polymer A is formed. The polymerization reaction and the conversion reaction may be carried out without changing the solvent.

[0048] The temperature at which the conversion reaction proceeds is, for example, 0 to 150° C., and may be 20 to 80° C. The time for which the conversion reaction proceeds is, for example, 1 to 72 hours, and may be 1 to 6 hours.

[0049] In the conversion reaction, substances other than those mentioned above can be added to the reaction system as long as the desired reaction proceeds. Examples of substances that can be added include lithium salts such as lithium trifluoromethanesulfonate, lithium chloride, and lithium bromide, and basic compounds such as triethylamine, pyridine, triazabicyclodecene, and diazabicycloundecene.

[0050] The conversion reaction may be carried out separately from the polymerization reaction, for example, successively after the completion of the polymerization reaction, or simultaneously with the polymerization reaction, for example, by starting the conversion reaction when the polymerization reaction has progressed to a certain extent, and allowing both reactions to proceed from that point onward.

[0051] The method for producing a polymer according to the first embodiment may include any step other than those described above, as long as it is possible to form polymer B. An example of such a step is a purification step of purifying polymer B formed by a conversion reaction. Examples of the purification step are purification by reprecipitation using various solvents such as methanol, and purification by dialysis using various solvents. Purification by reprecipitation may be selected when polymer B has low solubility in the solvent used for purification, and purification by dialysis may be selected when polymer B has high solubility. However, the specific methods of the optional step and the purification step are not limited to the above examples.

[0052] In the purification step, a substance containing the chemical structure shown in formula (4) that was eliminated during the alcohol substitution reaction or the amine substitution reaction may be recovered. For example, a solvent having a different solubility between the substance and polymer B may be used for recovery. The recovered substance may be reused for forming monomer a. For example, this can be achieved by bonding a hydrogen atom to the wavy line portion in the chemical structure of formula (4). An acidification reaction may be used to bond the hydrogen atom. For example, a saturated solution of sodium bicarbonate (NaHCO3) may be used for the acidification reaction. The ability to reuse the eliminated chemical structure is extremely advantageous and useful from the industrial and environmental protection perspectives. [ka]

[0053] <<Second embodiment: Polymer B>> The polymer of the second embodiment is an isotactic polymer B composed of structural units shown in the following formula (3). 1 , R 3 and R 4 is as described above. [ka]

[0054] The isotacticity of the polymer B of the second embodiment is, for example, 70% or more, and may be 73% or more, 75% or more, 78% or more, 80% or more, 81% or more, 82% or more, 83% or more, 84% or more, 85% or more, 86% or more, 87% or more, 88% or more, 89% or more, 90% or more, 91% or more, 92% or more, 93% or more, 94% or more, 95% or more, 96% or more, 97% or more, 98% or more, or even 99% or more. The upper limit of the isotacticity is 100% or less, and may be 99.5% or less.

[0055] Examples of the polymer B of the second embodiment include N-methyl(meth)acrylamide, N-ethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N-(n-butyl)(meth)acrylamide, N-(n-hexyl)(meth)acrylamide, N-(n-octyl)(meth)acrylamide, N-(2-ethylhexyl)(meth)acrylamide, N-cyclobutyl(meth)acrylamide, N-cyclopentyl(meth)acrylamide, N-cyclohexyl(meth)acrylamide, N-cyclopentyl(meth)acrylamide, and N-cyclooctyl(meth)acrylamide. Polymer B may be a polymer of each of the (meth)acrylamides, such as N-(2-hydroxyethyl)(meth)acrylamide, N-benzyl(meth)acrylamide, N-naphthylmethyl(meth)acrylamide, N-(N,N-dimethylethyl)(meth)acrylamide, N-allyl(meth)acrylamide, N-(2-hydroxyethyl)(meth)acrylamide, N-[(2-methoxy)ethyl](meth)acrylamide, N-(ethylimidazole)(meth)acrylamide, N,N-diethyl(meth)acrylamide, N,N-di(n-butyl)(meth)acrylamide, and 4-(meth)acryloylmorpholine. Polymer B may also be a polymer of each of the acrylamides. However, polymer B is not limited to the above examples.

[0056] An isotactic polymer B may have different physical properties from a non-isotactic polymer of the same type, such as an atactic polymer of the same type. Examples of different physical properties include increased crystallinity, a decreased glass transition temperature (Tg), and decreased solubility in water. The difference in physical properties is presumably due to the stereoregularity inherent to isotactic polymers, in which side chains are aligned in the same direction relative to the main chain.

[0057] Polymer B may take other forms, including the preferred forms, as described above in the description of the first embodiment.

[0058] <<Third embodiment: Method for producing polymer A>> The method for producing a polymer according to the third embodiment includes polymerizing a monomer a shown in the following formula (1) to form an isotactic polymer A.1 and R 2 is as described above. [ka]

[0059] The method for polymerizing monomer a to form polymer A, including preferred embodiments thereof, is as described above in the description of the first embodiment. The aspects of the formed polymer A, including preferred embodiments thereof, are as described above in the description of the first embodiment. The polymer A formed by the method for producing a polymer according to the third embodiment usually has isotactic stereoregularity.

[0060] The isotacticity of the polymer A formed by the polymer production method according to the third embodiment may be 95% or more, 96% or more, 97% or more, 98% or more, 99% or more, or even 99.5% or more.

[0061] <<Fourth embodiment: Polymer A>> The polymer according to the fourth embodiment is an isotactic polymer A composed of structural units represented by the following formula (2): 1 and R 2 The aspects of polymer A, including preferred aspects, are as described above in the description of the first embodiment. [ka]

[0062] The isotacticity of the polymer A according to the fourth embodiment may be 95% or more, 96% or more, 97% or more, 98% or more, 99% or more, or even 99.5% or more.

[0063] <<Polymer Applications>> Polymer A and polymer B can be used in a variety of applications. Examples of applications include plastic materials, elastomer materials, rubber materials, temperature-responsive materials, adhesives, etc. The applications may utilize the physical properties of polymer A and polymer B resulting from the stereoregularity, such as improved crystallinity, decreased Tg, and decreased solubility in water compared to polymers without stereoregularity.

[0064] <<Derivative manufacturing method>> The method for producing a polymer according to the first embodiment and the method for producing a polymer according to the third embodiment can be applied to a method for producing at least one derivative selected from the group consisting of derivatives of (meth)acrylate polymers and derivatives of (meth)acrylamide polymers. In the method for producing a derivative, a person skilled in the art can arbitrarily select a step for obtaining a derivative from at least one polymer selected from the group consisting of (meth)acrylate polymers and (meth)acrylamide polymers.

[0065] Similarly, the method for producing a polymer according to the third embodiment can be applied to the production of a polymer that is a derivative of polymer A and is other than a (meth)acrylate polymer or a (meth)acrylamide polymer. [Example]

[0066] The present invention will be described in more detail below with reference to examples, but is not limited to the specific embodiments shown below.

[0067] <<Evaluation Method>> <nmr> 1 1H-NMR spectrum and 13 13C-NMR spectrum were evaluated at room temperature using a JEOL JNM-ECA500 with resonance frequencies of 500.16 MHz ( 1 1H) and 125.04 MHz ( 13 13C). CDCl3, DMSO-d6, (CDCl2)2, or CD3OD was used as the deuterated solvent.

[0068] <Mn, Mw and Mw / Mn> The number-average molecular weight (Mn), weight-average molecular weight (Mw), and molecular weight distribution (Mw / Mn) of the polymer were evaluated by gel permeation chromatography (GPC) or size exclusion chromatography (SEC). The evaluation conditions for GPC and SEC are as follows. [GPC] (applied to Example Group 1) · Instrument: Tosoh Corporation, HLC-8320GPC · Measurement temperature: 40 °C · Eluent: Tetrahydrofuran (THF) · Column: Two polystyrene gel columns (Shodex HPLC column LF-404) in series. The columns were calibrated with polymethyl methacrylate (PMMA; Polymer Laboratories, Mp = 625 - 1250000, Mw / Mn = 1.02 - 1.30). [SEC] (applied to Example Group 2) · Measurement temperature: 40 °C · Eluent: THF or dimethylformamide (DMF) containing LiBr at a concentration of 10 mmol / L · When the eluent is THF: Three polystyrene gel columns (Shodex HPLC column LF-404) were connected in series to a Tosoh Corporation, HLC-8320GPC, and the flow rate was set to 0.35 mL / min. When the eluent was DMF, three polystyrene gel columns (Shodex HPLC column KF-805L) were connected in series to a precision pump (JASCO, PU-2080), a refractive index (RI) detector (JASCO, PU-2080), and an ultraviolet-visible spectrophotometer (UV / vis) detector (JASCO, UV-2075). The flow rate was 1.0 mL / min. The column was calibrated with PMMA (Polymer Laboratories, Mn=800-2200000).

[0069] <Thermal properties> [Thermal response characteristics] The thermal response characteristics of the polymer in aqueous solution were evaluated by measuring the transmittance of the aqueous solution while changing the temperature using an ultraviolet-visible-infrared spectrophotometer (JASCO Corporation, V-750) under conditions of an optical path length of 1.0 cm and a wavelength of 670 nm.

[0070] [Glass transition temperature and crystallinity] The glass transition temperature (Tg) of the polymer was evaluated by differential scanning calorimetry (DSC) using a TA Instruments DSC Q200 calorimeter (equipped with an RCS90 electric refrigerator). The evaluation was performed by placing the dried polymer in an aluminum pan (Tzero pan). The sample weight was approximately 2.0–6.0 mg. DSC was performed using the following temperature program. Considering the possibility that sample preparation conditions might affect the measured values, Tg was determined based on the DSC curve obtained from the second heating run, and its validity and reproducibility were confirmed by the value determined from the DSC curve obtained from the third heating run. The same temperature program was also used for DSC to evaluate the crystallinity of the polymer. (Temperature Program) 1. Heat from 40°C to 260°C at a rate of 10°C / min (first heating) 2.Hold at 260℃ for 5 minutes 3. Cool to -10°C at a rate of 10°C / min. 4. Keep at -10℃ for 5 minutes 5. Heat to 260°C at a rate of 10°C / min (second heating) 6. Hold at 260℃ for 5 minutes 7. Cool to -10°C at a rate of 10°C / min. 8. Keep at -10℃ for 5 minutes 9. Heat to 260°C at a rate of 10°C / min (third heating) 10. Hold at 260℃ for 5 minutes

[0071] <<Purification method>> Based on its solubility in methanol, the converted polymer B was purified by one of the following methods: (I) reprecipitation in methanol, (II) recycling preparative GPC (column: KF-5001 manufactured by JASCO Corporation or Wako Gel C200 manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), or (III) methanol dialysis (using a dialysis membrane, Spectrapore VR7 of MECO1000, diameter 29 mm).

[0072] <<Example Group 1>> In Example Group 1, R 1 is a hydrogen atom, R 2 An example using monomer a in which is an isopropyl group will be described. [ka]

[0073] [Synthesis Example 1: Synthesis of Monomer a] I: Synthesis of 4-isopropyl-2H-benzo[e][1,2,4]thiadiazin-3(4H)-one 1,1-dioxide (iPrBTD) First, iPrBTD, a precursor of monomer a, was synthesized according to the following scheme. [ka]

[0074] A solution of chlorosulfonyl isocyanate (33.2 mL, 1.1 equivalents) dissolved in 170 mL of nitromethane was mixed with a solution of N-isopropylaniline (50.0 mL, 1.0 equivalents) dissolved in 160 mL of nitromethane at -40 °C. The mixture was stirred for 15 minutes, and then AlCl3 (46.4 g, 1.0 equivalents) was added. The mixture was heated to 110 °C and stirred for an additional 45 minutes. The stirred solution was then cooled and poured into a large amount of ice water (1.2 L). The resulting filtrate was filtered, and the crude product was washed several times with toluene and hexane. It was then dissolved in hot ethanol and recrystallized by cooling to obtain iPrBTD (29.2 g, 35.0% yield) as a white solid. The obtained iPrBTD 1 H-NMR spectrum and 13 The C-NMR spectrum is shown in Figure 1. The chemical shifts of the peaks in the NMR spectrum were as follows: NMR measurements were carried out in CDCl3 at room temperature (25°C). 1 H-NMR (500MHz, CDCl3): δ(ppm)=7.88(dd,1H),7.65(m,1H),7.39(d,1H),7.32(t,1H),4.53(m,1H),1.65(d,6H) 13 C-NMR(125MHz,CDCl3):δ(ppm)=150.75,138.13,133.84,127.74,123.93,122.67,117.83,52.86,20.26

[0075] II: Synthesis of Monomer a, 2-Acryloyl-4-isopropyl-2H-benzo[e][1,2,4]thiadiazin-3(4H)-one 1,1-dioxide, from iPrBTD Next, monomer a was synthesized from iPrBTD according to the following scheme. [ka]

[0076] iPrBTD (6.0 g, 25.0 mmol) and phenothiazine (60.0 mg, 0.3 mmol) as a radical polymerization inhibitor were placed in a round-bottom flask and dissolved in tetrahydrofuran (THF; 60.0 mL). Next, triethylamine (EtN; 3.8 mL, 27.3 mmol) was added, followed by the slow addition of acryloyl chloride (2.1 mL, 26.0 mmol) at 0 °C. The mixture was stirred for 20 min, and then the solvent was evaporated from the reaction mixture. The residue after evaporation was dissolved in CHCl, and the resulting solution was washed with saturated aqueous NaHCO and brine. The organic layer was then dried over anhydrous NaSO, and the solvent was evaporated. The temperature during evaporation was kept below 30 °C to suppress the polymerization reaction. The solid obtained as described above was washed with diethyl ether and hexane to obtain 2-acryloyl-4-isopropyl-2H-benzo[e][1,2,4]thiadiazin-3(4H)-one 1,1 dioxide, which is monomer a, as a white solid (4.6 g, yield 62.0%). Washing with diethyl ether and hexane was continued until the red color of the solid disappeared in order to remove phenothiazine. 1 H-NMR spectrum and 13 The C-NMR spectrum is shown in Figure 2. The chemical shifts of the peaks in the NMR spectrum were as follows: NMR measurements were carried out in CDCl3 at room temperature. 1 H-NMR (500MHz, CDCl3): δ(ppm)=7.90(dd,1H),7.69(m,1H),7.41(d,1H),7.3 5(t,1H),6.52(dd,1H),6.38(dd,1H),5.91(dd,1H),4.50(m,1H),1.65(d,6H) 13 C-NMR(125MHz,CDCl3):δ(ppm)=163.46,148.76,137.93,134.52,132.40,130.67,128.70,124.62,123.68,118.77,54.40,20.22

[0077] [Example 1: Formation of polymer A and polymer B from monomer a] In Example 1, the monomer a prepared in Synthesis Example 1 was polymerized to form a polymer A, and the formed polymer A was subjected to an alcohol substitution reaction to obtain a polymer B, which was a methyl acrylate polymer (PMA).

[0078] Under dry argon, Monomer a (0.1940 g, 0.66 mmol) prepared in Synthesis Example 1, lithium trifluoromethanesulfonate (LiOTf; 9.9 mg, 63.5 μmol), azobisisobutyronitrile (AIBN; 2.1 mg, 12.8 μmol), 2.4 mL of (CHCl) as a polymerization solvent, and a small amount of tetralin as an internal standard were added to a Schlenk tube in this order at room temperature to obtain a polymerization solution with the following concentration: [Monomer a] / [LiOTf] / [AIBN]=250 / 25 / 5 (mmol / L). Next, the Schlenk tube was immersed in an oil bath at 60°C, and the polymerization reaction was allowed to proceed for 2 hours. Next, a portion of the obtained polymerization solution was withdrawn and diluted with CDCl, and then 1 The monomer conversion rate was evaluated by H-NMR. The monomer conversion rate was 80.1%. The monomer conversion rate was determined by comparing the integral of the olefinic proton peak area relative to the tetralin peak area with that before heating. The method for determining the monomer conversion rate was the same in each of the following examples.

[0079] Next, 2.0 mL of the resulting polymerization solution was diluted with 3.0 mL of anhydrous CHCl, and phenothiazine (polymerization inhibitor, 20.0 mg), anhydrous methanol (0.40 mL, 9.9 mmol), and EtN (0.35 mL, 2.5 mmol) were added to proceed with the alcohol substitution reaction. The resulting mixture was immersed in a 60°C oil bath and stirred for 42 hours. As the alcohol substitution reaction progressed, the solution gradually became homogeneous. The resulting solution was filtered through Celite and washed with (CHCl), and the filtrate was evaporated under reduced pressure. The solid obtained by evaporation was dissolved in CHCl, and the resulting solution was passed through a PTFE filter (pore size 0.45 μm) and injected into a preparative SEC (eluent: CHCl) to remove low molecular weight compounds. The product (42.9 mg) obtained as described above was analyzed. 1 The H-NMR spectrum was similar to that of PMA obtained by radical polymerization of methyl acrylate monomer, confirming that the product was PMA. 1 The stereoregularity of the product was confirmed by H-NMR spectroscopy, and the ratio of m (meso diad) to r (racemo diad) was m:r = 74:26, i.e., the isotacticity of the product was 74%. 1 The isotacticity of the polymer evaluated by H-NMR was almost unchanged, suggesting that the isotacticity of the polymer before the alcohol substitution reaction was similar. The Mn of the product was 16,400, and the Mw / Mn ratio was 1.89.

[0080] Next, the polymerization reaction of monomer a and subsequent conversion reaction were carried out in the same manner as above, except that 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile; also known as V-70) was used instead of AIBN as the polymerization initiator and the polymerization temperature was changed to 30°C. PMA was also obtained. The monomer conversion in the polymerization reaction was 83.1%, and the isotacticity of the resulting PMA was 78%, Mn was 12,400, and Mw / Mn was 2.62.

[0081] Next, the polymerization reaction of monomer a and subsequent conversion reactions were carried out in the same manner as above, except that the concentration of the polymerization solution was changed to [monomer a] / [LiOTf] / [AIBN] = 100 / 10 / 2 mmol / L, V-70 was used instead of AIBN as the polymerization initiator, and the polymerization temperature was changed to 30 °C. PMA was also obtained. The monomer conversion in the polymerization reaction was 68.3%, and the isotacticity of the resulting PMA was 81%, Mn was 11,500, and Mw / Mn was 2.30.

[0082] [Example 2: Formation of polymer A and polymer B from monomer a] In Example 2, the monomer a prepared in Synthesis Example 1 was polymerized to form a polymer A, and the formed polymer A was subjected to an alcohol substitution reaction to form a polymer B, which was PMA.

[0083] Under dry argon, Monomer a (0.2668 g, 0.91 mmol) prepared in Synthesis Example 1, LiOTf (14.0 mg, 89.7 μmol), AIBN (3.0 mg, 18.3 μmol), 8.8 mL of (CHCl) as a polymerization solvent, and a small amount of tetralin as an internal standard were added to a Schlenk tube in this order at room temperature to obtain a polymerization solution with the following concentration: [Monomer a] / [LiOTf] / [AIBN] = 100 / 10 / 2 (mmol / L). Next, the Schlenk tube was immersed in cooled methanol at -20°C and irradiated with UV light from a UV LED lamp (CCS, LDL-71X12UV3-365-N, λ = 365 nm, 7.6 W) positioned approximately 10 cm away from the Schlenk tube. Polymerization was initiated by UV irradiation. The ultraviolet light was continuously irradiated for 24 hours at −20° C. After the irradiation was stopped, a portion of the polymerization solution was taken out and diluted with CDCl 3 , and the monomer conversion rate was evaluated in the same manner as in Example 1, and was found to be 86.4%.

[0084] Next, phenothiazine (polymerization inhibitor, 30.0 mg), anhydrous methanol (0.73 mL, 18.0 mmol), and Et3N (0.63 mL, 4.5 mmol) were added to the resulting polymerization solution to allow the alcohol substitution reaction to proceed. The resulting mixture was immersed in a 60°C oil bath and stirred for 42 hours. As the alcohol substitution reaction proceeded, the solution gradually became homogeneous. The resulting solution was filtered through Celite and washed with (CHCl2), after which the filtrate was evaporated under reduced pressure. The solid obtained by evaporation was dissolved in CHCl3, and the resulting solution was passed through a PTFE filter (pore size 0.45 μm) and injected into a preparative SEC (eluent: CHCl3) to remove low molecular weight compounds. The product (31.5 mg) obtained as described above was 1 The H-NMR spectrum was similar to that of PMA obtained by radical polymerization of methyl acrylate monomer, confirming that the product was PMA. 1 The stereoregularity of the product was confirmed by H-NMR spectroscopy to be m:r = 90:10, i.e., the isotacticity of the product was 90%. The isotacticity of the polymer before the alcohol substitution reaction was also considered to be similar. The Mn of the product was 9,400, and the Mw / Mn ratio was 1.78.

[0085] [Example 3: Formation of polymer A from monomer a] In Example 3, the monomer a prepared in Synthesis Example 1 was polymerized to form a polymer A.

[0086] Under dry argon, Monomer a (1.5 g, 5.1 mmol) prepared in Synthesis Example 1, LiOTf (79.5 mg, 0.51 mmol), AIBN (16.7 mg, 0.10 mmol), 49.5 mL of (CHCl) as a polymerization solvent, and a small amount of tetralin as an internal standard were added to a Schlenk tube in this order at room temperature to obtain a polymerization solution with the following concentration: [Monomer a] / [LiOTf] / [AIBN] = 100 / 10 / 2 (mmol / L). Next, the Schlenk tube was immersed in cooled methanol at -40 °C and irradiated with UV light from a UV LED lamp (CCS, LDL-71X12UV3-365-N, λ = 365 nm, 7.6 W) placed approximately 10 cm away from the Schlenk tube. Polymerization was initiated by UV irradiation. UV irradiation was continued at -40 °C for 24 hours. After the irradiation was stopped, a portion of the polymerization solution was taken out and diluted with CDCl, and the monomer conversion rate was evaluated as in Example 1, which was found to be 80.8%. The obtained polymerization solution was stored at -20°C, and a portion of it was used in the conversion reaction in the examples described later.

[0087] Example 4: Formation of polymer B from polymer A In Example 4, the polymer A prepared in Example 3 was subjected to an alcohol substitution reaction to form polymer B, which was PMA.

[0088] The alcohol substitution reaction was carried out by adding phenothiazine (polymerization inhibitor, 20.0 mg), anhydrous methanol (0.40 mL, 9.9 mmol), and EtN (0.35 mL, 2.5 mmol) to 5.0 mL of the polymerization solution prepared in Example 3. The resulting mixture was immersed in an oil bath at 60°C and stirred for 42 hours. As the alcohol substitution reaction proceeded, the solution gradually became homogeneous. The resulting solution was filtered through Celite and washed with (CHCl), after which the filtrate was evaporated under reduced pressure. The solid obtained by evaporation was dissolved in CHCl, and the resulting solution was passed through a PTFE filter (pore size 0.45 μm) and injected into a preparative SEC (eluent: CHCl) to remove low molecular weight compounds. The product (27.5 mg) obtained as above was 1 The H-NMR spectrum was similar to that of PMA obtained by radical polymerization of methyl acrylate monomer, confirming that the product was PMA. 1 The stereoregularity of the product was confirmed by H-NMR spectrum to be m:r=93:7, that is, the isotacticity of the product was 93%. The Mn of the product was 11,300, and the Mw / Mn was 2.21. 1 H-NMR spectrum and 13 The C-NMR spectra are shown in Figure 3 and Figures 4A and 4B, respectively. Figure 4B is an enlarged view of the dashed line portion in the spectrum of Figure 4A. 1 Peak a observed in the H-NMR spectrum m and a r are the peaks derived from the meso-dyad and the racemo-dyad, respectively. Both peaks were sharp, corresponding to the high isotacticity of the product. Also, as shown in Figure 4B, 13 In the C-NMR profile, a sharp peak due to mesohexadecano (mmmmm) was observed. 1 H-NMR measurements were carried out in CDCl3 at room temperature. 13 C-NMR measurements were carried out in CDCl3 at 55 °C.

[0089] The polymerization conditions for monomer a in Examples 1-4, the monomer conversion rate when polymer A was formed from monomer a, and the physical properties of polymer B finally obtained are summarized in Table 1 below.

[0090] [Table 1]

[0091] As shown in Table 1, it was confirmed that the lower the concentration of monomer a in the polymerization solution used for polymerization and the lower the polymerization temperature, the higher the isotacticity of the finally obtained polymer B. Furthermore, since the isotacticity is considered to be almost maintained in the conversion reaction from polymer A to polymer B, it was considered that the lower the concentration of monomer a in the polymerization solution used for polymerization and the lower the polymerization temperature, the higher the isotacticity of polymer A.

[0092] Example 5: Formation of polymer B from polymer A In Example 5, the polymer A produced in Example 3 was subjected to an alcohol substitution reaction to form a polymer B, which was an n-butyl acrylate polymer (PBA).

[0093] The alcohol substitution reaction was carried out by adding phenothiazine (polymerization inhibitor, 20.0 mg), anhydrous n-butanol (0.92 mL, 10.1 mmol), and Et3N (0.35 mL, 2.5 mmol) to 5.0 mL of the polymerization solution prepared in Example 3. The resulting mixture was immersed in an oil bath at 80°C and stirred for 42 hours. As the alcohol substitution reaction proceeded, the solution gradually became homogeneous. The resulting solution was filtered through Celite and washed with (CHCl2), after which the filtrate was evaporated under reduced pressure. The solution remaining after evaporation was then injected into a preparative SEC (eluent: CHCl3) to remove low molecular weight compounds. The product obtained as described above was 1 The H-NMR spectrum was similar to that of PBA obtained by radical polymerization of n-butyl acrylate monomer, confirming that the product was PBA. 1 The H-NMR profile is shown in Figure 5. 1 Several minor peaks were also observed in the H-NMR profile. The isotacticity of the product was considered to be about 93%, the same as that of the product of Example 4 obtained by subjecting the polymer A prepared in Example 3 to an alcohol substitution reaction. 1 H-NMR measurements were carried out in CDCl3 at room temperature.

[0094] [Reference Example 1: Alcohol substitution reaction of monomer a] In Reference Example 1, an alcohol substitution reaction was attempted on the monomer a prepared in Synthesis Example 1.

[0095] Monomer a (29.4 mg, 0.10 mmol) prepared in Synthesis Example 1 and methanol (20.0 μL, 0.49 mmol) were mixed in CDCl3 (0.95 mL). After 4 hours, the mixture 1 The progress of the alcohol substitution reaction was evaluated based on the integral ratio of the peaks derived from the starting material, monomer a, and PMA, the product of the alcohol substitution reaction. The progress was less than 1%, confirming that the alcohol substitution reaction of monomer a hardly proceeded.

[0096] Example 6: Formation of polymer B from polymer A In Example 6, the polymer A prepared in Example 3 was subjected to an amine substitution reaction to form polymer B, which was an acrylamide polymer.

[0097] Phenothiazine (polymerization inhibitor, 20.0 mg) was added to 5.0 mL of the polymerization solution prepared in Example 3. Next, the resulting mixed solution was evaporated under reduced pressure, and 5.0 mL of anhydrous THF was added. Next, isopropylamine (0.43 mL, 5.0 mmol) was slowly added, and the resulting mixture was immersed in an oil bath at 60°C and stirred for 18 hours. After stirring, the solution was purified by precipitation in methanol, and the precipitate was washed with methanol and dried under vacuum. The product (40.7 mg) obtained as above was 1 The H-NMR spectrum was similar to that of commercially available N-isopropylacrylamide polymer (PNIPAM), confirming that the product was PNIPAM. 1 The stereoregularity of the product was confirmed by H-NMR spectroscopy to be m:r = 95:5, i.e., the isotacticity of the product was 95%. The Mn and Mw / Mn of the product could not be measured due to the low solubility of the product in the eluent. The weight of the obtained product (40.7 mg) was comparable to the ideal value (45.7 mg) for quantitative conversion and lossless purification, confirming the validity of methanol precipitation purification for isotactic PNIPAM.

[0098] Next, the amine substitution reaction of monomer a was carried out in the same manner as above, except that benzylamine, cyclohexylamine, n-butylamine, or N,N-dimethylethyleneamine was used instead of isopropylamine. 1 The H-NMR spectra are shown in Figure 6. It was confirmed that the respective reactions resulted in the formation of polymers of acrylamide, namely, N-benzyl acrylamide, N-cyclohexyl acrylamide, N-(n-butyl) acrylamide, and N-(N,N-dimethylethylene) acrylamide. 1 The stereoregularity of each product was confirmed by H-NMR spectrum, and the isotacticity of N-benzylacrylamide polymer was 95%. The isotacticity of N-cyclohexylacrylamide polymer, N-(n-butyl)acrylamide polymer, and N-(N,N-dimethylethylene)acrylamide polymer was also considered to be at the same level. The N-(n-butyl)acrylamide polymer was purified by precipitation with acetone instead of methanol. The N-(N,N-dimethylethylene)acrylamide polymer was purified by methanol dialysis. 1 H-NMR measurements were carried out in DMSO-d at 150 °C.

[0099] Next, the amine substitution reaction of monomer a was carried out in the same manner as above, except that n-hexylamine or n-octylamine was used instead of isopropylamine. 1 H-NMR spectra of atactic N-(n-octyl)acrylamide polymers prepared separately by radical polymerization 1 The results are shown in Figure 7 together with the H-NMR spectrum. It was confirmed that N-(n-hexyl)acrylamide polymer and N-(n-octyl)acrylamide polymer were formed in each reaction, respectively. The isotacticity of the N-(n-hexyl)acrylamide polymer and N-(n-octyl)acrylamide polymer was considered to be similar to that of the N-benzyl acrylamide polymer formed above. Note that the isotacticity of the atactic N-(n-octyl)acrylamide polymer was 1 Peak a originating from the racemo dyad in the H-NMR spectrum r is the isotactic N-(n-octyl)acrylamide polymer formed by the above reaction. 1 a observed in H-NMR spectrum r was significantly larger than that of each product. 1 H-NMR measurements were carried out in (CDCl2)2 at 130 °C.

[0100] Next, the amine substitution reaction of the monomer a was carried out in the same manner as above, except that 2-hydroxyethylamine was used instead of isopropylamine. 1 The H-NMR spectrum is shown in Figure 8. It was confirmed that N-(2-hydroxyethyl)acrylamide polymer was formed by the amine substitution reaction. The isotacticity of the N-(2-hydroxyethyl)acrylamide polymer was considered to be similar to that of the N-benzyl acrylamide polymer formed above. However, the formation of the by-product 2-aminoethyl acrylate was confirmed in an amount of 4 mol % or less. The N-(2-hydroxyethyl)acrylamide polymer was purified by methanol dialysis. 1 H-NMR measurements were carried out in DMSO-d at 150 °C.

[0101] [Example 7: Formation of polymer A and polymer B from monomer a] In Example 7, the monomer a prepared in Synthesis Example 1 was polymerized to form a polymer A, and the formed polymer A was subjected to an amine substitution reaction to form an acrylamide polymer, polymer B. Note that LiOTf was not added to the polymerization system of the monomer a.

[0102] Under dry argon, Monomer a (0.20 g, 0.68 mmol) prepared in Synthesis Example 1, AIBN (2.1 mg, 12.8 μmol), 6.6 mL of (CHCl) as a polymerization solvent, and a small amount of tetralin as an internal standard were added to a Schlenk tube in this order at room temperature to obtain a polymerization solution with the following concentration: [Monomer a] / [AIBN] = 100 / 2 (mmol / L). Next, the Schlenk tube was immersed in cooled methanol at -40°C and irradiated with UV light from a UV LED lamp (CCS, LDL-71X12UV3-365-N, λ = 365 nm, 7.6 W) placed approximately 10 cm away from the Schlenk tube. Polymerization was initiated by UV irradiation. UV irradiation was continued at -40°C for 24 hours. After the irradiation was stopped, a portion of the polymerization solution was taken out and diluted with CDCl3, and the monomer conversion rate was evaluated in the same manner as in Example 1, and was found to be 99%.

[0103] Next, the resulting mixture was evaporated under reduced pressure, and then 6.6 mL of anhydrous THF was added. Next, isopropylamine (0.58 mL, 6.7 mmol) was slowly added, and the resulting mixture was immersed in an oil bath at 60°C and stirred for 18 hours. The solution after stirring was purified by precipitation into methanol, and the precipitate was washed with methanol and dried under vacuum. The product (65.4 mg) obtained as above was 1 The H-NMR spectrum (see Figure 9) was similar to that of commercially available PNIPAM, confirming that the product was PNIPAM. 1 The stereoregularity of the product was confirmed by H-NMR spectrum to be m:r=95:5, i.e., the isotacticity of the product was 95%. The Mn and Mw / Mn of the product could not be measured due to the low solubility of the product in the eluent. 1 H-NMR measurements were carried out in DMSO-d at 150 °C.

[0104] [Reference Example 2: Amine substitution reaction of monomer a] In Reference Example 2, an amine substitution reaction was attempted on the monomer a prepared in Synthesis Example 1.

[0105] Monomer a (29.4 mg, 0.10 mmol) prepared in Synthesis Example 1 and isopropylamine (42.8 μL, 0.50 mmol) were mixed in CDCl (0.93 L). After 15 minutes, the mixture 1 We attempted to evaluate the progress of the amine substitution reaction by measuring the H-NMR spectrum based on the integral ratio of the peaks derived from the starting material, monomer a, and PNIPAM, the product of the amine substitution reaction if it had proceeded. However, the appearance of multiple complex peaks that were thought to be due to numerous side reactions made it impossible to assess the progress of the reaction.

[0106] <<Example Group 2>> In Example Group 2, R 1 is a hydrogen atom, R 2 An example using a monomer a in which is a methyl group, an isopropyl group, or a phenyl group will be described. [ka]

[0107] [Synthesis Example 2: Synthesis of Monomer a] I: Synthesis of 4-methyl-2H-benzo[e][1,2,4]thiadiazin-3(4H)-one 1,1-dioxide (Me-CBS) First, Me-CBS, a precursor of monomer a, was synthesized according to the following scheme. [ka]

[0108] A solution of N-methylaniline (34.0 mL, 1.0 equiv., 314 mmol) in 175 mL of nitromethane was added to a solution of chlorosulfonyl isocyanate (30.0 mL, 1.1 equiv., 348 mmol) in 175 mL of nitromethane at -40 °C. The mixture was stirred for 15 min, and then AlCl3 (46.0 g, 1.1 equiv., 345 mmol) was added. The mixture was heated to 110 °C and stirred for an additional 45 min. The cooled solution was poured into a saturated solution of sodium bicarbonate (NaHCO3) (2000 mL, 1:1 volume ratio, water / methanol mixture). The resulting mixture was treated with charcoal and centrifuged to obtain the supernatant. The resulting homogeneous solution was acidified with hydrochloric acid to pH = 1, and the precipitate was suction filtered to obtain Me-CBS (21.2 g, 31.9% yield) as a white solid. The obtained Me-CBS 1 H-NMR spectrum and 13 The chemical shifts of the peaks in the C-NMR spectrum were as follows: NMR measurements were carried out in acetone-d6 at room temperature. 1 H-NMR (500MHz, CDCl3): δ(ppm)=10.81(brs,1H),7.86(dd,1H),7.78(m,1H),7.53(d,1H),7.40(m,1H),3.51(s,1H) 13 C-NMR(125MHz,CDCl3):δ(ppm)=150.04,137.69,134.31,126.33,123.45,129,96,116.83,31.32

[0109] II: Synthesis of 2-acryloyl-4-methyl-2H-benzo[e][1,2,4]thiadiazin-3(4H)-one 1,1-dioxide (monomer a; Me-CBSAm) from Me-CBS Next, the synthesis of monomer a (Me-CBSAm) from Me-CBS was carried out according to the following scheme. [ka]

[0110] Me-CBS (3.00 g, 14.1 mmol) and phenothiazine (30.0 mg, 0.150 mmol) as a radical polymerization inhibitor were placed in a round-bottom flask and dissolved in THF (30.0 mL). Next, EtN (2.2 mL, 1.1 equiv., 15.8 mmol) was added, followed by the slow addition of acryloyl chloride (1.2 mL, 1.05 equiv., 14.9 mmol) at 0 °C. The mixture was stirred for 1 h, and then the solvent was evaporated from the reaction mixture. The residue after evaporation was dissolved in CHCl, and the resulting solution was washed with saturated aqueous NaHCO and brine. The organic layer was then dried over anhydrous NaSO, and the solvent was evaporated. The temperature during evaporation was kept below 30 °C to suppress polymerization. The solid obtained as above was washed with diethyl ether and hexane and recrystallized from 1,2-dichloroethane at -40°C to obtain 2-acryloyl-4-methyl-2H-benzo[e][1,2,4]thiadiazin-3(4H)-one 1,1-dioxide as monomer a as a light gray solid (1.7 g, yield 45.2%). 1 H-NMR spectrum and 13 The chemical shifts of the peaks in the C-NMR spectrum were as follows: NMR measurements were carried out in CDCl3 at room temperature. 1 H-NMR (500MHz, CDCl3): δ(ppm)=7.94(dd,1H),7.74(m,1H),7.37(m,1H),7.33(d,1H),6.54(dd,1H),6.39(dd,1H),5.93(dd,1H),3.57(s,3H) 13 C-NMR(125MHz,CDCl3):δ(ppm)=163.44,149.49,137.07,134.95,132.95,130.60,127.12,124.50,123.71,117.05,33.31

[0111] [Synthesis Example 3: Synthesis of Monomer a] I: Synthesis of 4-phenyl-2H-benzo[e][1,2,4]thiadiazin-3(4H)-one 1,1-dioxide (Ph-CBS) First, Ph-CBS, a precursor of monomer a, was synthesized according to the following scheme. [ka]

[0112] A solution of chlorosulfonyl isocyanate (14.0 mL, 1.1 equivalents, 162.2 mmol) in 80 mL of nitromethane was mixed with a solution of diphenylaniline (147.7 mmol) in 80 mL of nitromethane at -40 °C. The mixture was stirred for 15 minutes, and then AlCl3 (19.7 g, 1.1 equivalents, 147.8 mmol) was added. The mixture was heated to 110 °C and stirred for an additional 45 minutes. The stirred solution was then cooled and poured into a large amount of ice water (1.2 L). The resulting filtrate was filtered, and the crude product was washed several times with toluene and hexane. It was then dissolved in hot ethanol, cooled, and recrystallized to obtain Ph-CBS (25.3 g, 62.4% yield) as a white solid. The resulting Ph-CSB was purified by filtration. 1 H-NMR spectrum and 13 The chemical shifts of the peaks in the C-NMR spectrum were as follows: NMR measurements were carried out in CDCl3 at room temperature. 1 H-NMR (500MHz, CDCl3): δ(ppm)=7.92(dd,1H),7.55(m,3H),7.45(m,1H),7.37(m,2H),7.30(m,1H),6.63(d,1H) 13 C-NMR (125MHz, CDCl3): δ(ppm)=149.75,137.97,136.19,133.99,130.40,129.68,129.28,125.62,124.10,122.54,118.69

[0113] II: Synthesis of 2-acryloyl-4-phenyl-2H-benzo[e][1,2,4]thiadiazin-3(4H)-one 1,1-dioxide (monomer a; Ph-CBSAm) from Ph-CBS Next, the synthesis of monomer a (Ph-CBSAm) from Ph-CBS was carried out according to the following scheme. [ka]

[0114] Ph-CBS (10.0 g, 36.5 mmol) and phenothiazine (100.0 mg, 0.5 mmol) as a radical polymerization inhibitor were placed in a round-bottom flask and dissolved in THF (100.0 mL) and acetone (200 mL). Next, triethylamine (5.6 mL, 40.2 mmol) was added, followed by the slow addition of acryloyl chloride (3.1 mL, 38.4 mmol) at 0 °C. The mixture was stirred for 30 minutes, and then the solvent was evaporated from the reaction solution. The residue after evaporation was dissolved in CHCl, and the resulting solution was washed with water and brine. The organic layer was then dried over anhydrous NaSO, and the solvent was evaporated. The solid obtained as above was washed with diethyl ether and hexane and recrystallized from 1,2-dichloroethane at -40°C to obtain 2-acryloyl-4-phenyl-2H-benzo[e][1,2,4]thiadiazin-3(4H)-one 1,1-dioxide as monomer a as a white solid (8.6 g, yield 71.8%). 1 H-NMR spectrum and 13 The chemical shifts of the peaks in the C-NMR spectrum were as follows: NMR measurements were carried out in CDCl3 at room temperature. 1 H-NMR (500MHz, CDCl3): δ(ppm)=7.97(dd,1H),7.54(m,5H),7.39(m,2H),7.34(m,1H),6.72(d,1H),6.58(dd,1H),6.48(dd,1H),5.96(dd,1H) 13 C-NMR (125MHz, CDCl3): δ(ppm)=163.45,148.87,137.64,136.40,134.48,133.02,130.59,130.39,129.79,129.07,126.98,124.63,123.44,119.46

[0115] [Example 8: Formation of polymer A and polymer B from monomer a] In Example 8, the monomers a prepared in Synthesis Examples 1 and 3 were polymerized to form polymer A, and the formed polymer A was subjected to an amine substitution reaction to form polymer B, which was an N-isopropylacrylamide polymer (PNIPAM).

[0116] Under dry argon, Monomer a (Ph-CBSAm; 0.18 g, 0.55 mmol) prepared in Synthesis Example 3, AIBN (1.8 mg, 11.0 μmol), 5.3 mL of (CHCl) as a polymerization solvent, and a small amount of tetralin as an internal standard were added to a Schlenk flask in this order at room temperature to obtain a polymerization solution with the following concentration: [Monomer a] / [AIBN]=100 / 2 (mmol / L). The Schlenk flask was then immersed in an oil bath at 60°C, and the polymerization reaction was allowed to proceed for 4 hours. A portion of the resulting polymerization solution was then withdrawn and diluted with CDCl. The monomer conversion was evaluated in the same manner as in Example 1, and was found to be 79.0%.

[0117] Next, 5.0 mL of the resulting polymerization solution was transferred to a new glass tube containing phenothiazine (polymerization inhibitor, 20.0 mg). The resulting mixture was evaporated under reduced pressure, followed by the addition of 5.0 mL of anhydrous THF. Isopropylamine (0.43 mL, 5.0 mmol) was then added, and the resulting mixture was immersed in an oil bath at 60 °C and stirred for 24 hours. The stirred solution was purified by precipitation into 10 volumes of methanol. The precipitate was centrifuged and decanted, washed with methanol, and dried under vacuum. As a result, 25.7 mg of PNIPAM was obtained as the product. 1 The stereoregularity of the product was confirmed by H-NMR spectrum, and it was m:r=94:6, that is, the isotacticity of the product was 94%. 1 Since the isotacticity of the polymer evaluated by H-NMR did not change, it was estimated that the isotacticity of the polymer before the amine substitution reaction was also at the same level. On the other hand, the tacticity of atactic PNIPAM was 48:52. The Mn and Mw / Mn of the product could not be measured due to the low solubility of the product in the eluent. 1 H-NMR measurements were carried out in DMSO-d at 150 °C.

[0118] The polymerization of Ph-CBSAm and subsequent conversion reactions were carried out in the same manner as above, except that V-70 was used instead of AIBN as the polymerization initiator and the polymerization temperature was changed to 30°C. PNIPAM was also obtained. The isotacticity of the resulting PNIPAM was 95%.

[0119] The polymerization reaction of monomer a and subsequent conversion reactions were carried out in the same manner as above, except that instead of Ph-CBSAm, Me-CBSAm or 2-acryloyl-4-isopropyl-2H-benzo[e][1,2,4]thiadiazin-3(4H)-one 1,1 dioxide (referred to as "iPr-CBSAm" in Example Group 2) was used as monomer a, and the polymerization reaction temperature was changed to 60°C or 30°C. PNIPAM was also obtained. V-70 was used as the polymerization initiator in the 30°C polymerization. The isotacticity of the PNIPAM obtained in each case is shown in Table 2 below.

[0120] [Table 2]

[0121] R in monomer a as shown in Table 2 2 The isotacticity of the resulting PNIPAM increased in the order of methyl, isopropyl, and phenyl groups. Furthermore, when the monomer a was the same, the lower the polymerization temperature, the higher the isotacticity of the resulting PNIPAM.

[0122] [Example 9: Formation of polymer A and polymer B from monomer a] In Example 9, the monomer a prepared in Synthesis Examples 1 and 3 was polymerized to form polymer A, and the formed polymer A was subjected to an amine substitution reaction to form polymer B, which was PNIPAM. The polymerization temperature for monomer a was set to 0°C or -40°C.

[0123] Under dry argon, Monomer a (Ph-CBSAm; 0.18 g, 0.55 mmol) prepared in Synthesis Example 3, AIBN (1.8 mg, 11.0 μmol), 5.3 mL of (CHCl) as a polymerization solvent, and a small amount of tetralin as an internal standard were added to a Schlenk tube in this order at room temperature to obtain a polymerization solution with the following concentration: [Monomer a] / [AIBN] = 100 / 2 (mmol / L). Next, the Schlenk tube was immersed in cooled methanol at 0°C and irradiated with UV light from a UV LED lamp (CCS, LDL-71X12UV3-365-N, λ = 365 nm, 7.6 W) placed approximately 10 cm away from the Schlenk tube. Polymerization was initiated by UV irradiation. UV irradiation was continued at 0°C for 24 hours. After the irradiation was stopped, a portion of the polymerization solution was taken out and diluted with CDCl3, and the monomer conversion rate was evaluated in the same manner as in Example 1, and was found to be over 99%.

[0124] Next, 5.0 mL of the resulting polymerization solution was transferred to a new glass tube containing phenothiazine (polymerization inhibitor, 20.0 mg). The resulting mixture was evaporated under reduced pressure, followed by the addition of 5.0 mL of anhydrous THF. Isopropylamine (0.43 mL, 5.0 mmol) was then slowly added, and the resulting mixture was immersed in an oil bath at 60 °C and stirred for 24 hours. The stirred solution was purified by precipitation into 10 volumes of methanol. The precipitate was centrifuged and decanted, washed with methanol, and dried under vacuum. As a result, 36.7 mg of PNIPAM was obtained as the product. 1 The stereoregularity of the product was confirmed by H-NMR spectrum to be m:r=97.3, i.e., the isotacticity of the product was 97%. 1 Since the isotacticity of the polymer evaluated by H-NMR did not change, it was estimated that the isotacticity of the polymer before the amine substitution reaction was also at the same level. The Mn and Mw / Mn of the product could not be measured due to the low solubility of the product in the eluent. 1 H-NMR measurements were carried out in DMSO-d at 150 °C.

[0125] Furthermore, during the above process, we successfully recovered the chemical structure that had been eliminated from the side chain of polymer A by the amine substitution reaction. Taking advantage of the difference in solubility in methanol between this chemical structure and PNIPAM, this chemical structure could be recovered in a purification process by precipitation into methanol. PNIPAM was obtained from the insoluble fraction, and a substance with the above chemical structure was obtained from the soluble fraction. The recovered substance was then dissolved in a saturated NaHCO3 solution in a mixed solvent of water and methanol (volume ratio 1:1) for acidification, resulting in the recovery of Ph-CBS in a 79% yield.

[0126] The polymerization reaction of monomer a and the subsequent conversion reaction were carried out in the same manner as above, except that Me-CBSAm or iPr-CBSAm prepared in Synthesis Example 1 was used instead of Ph-CBSAm as monomer a, and the polymerization reaction temperature was set to 0°C or -40°C. PNIPAM was also obtained. For polymerization at -40°C, cooled methanol was used. The isotacticity of the PNIPAM obtained in each case is shown in Table 3 below. Furthermore, for the example in which monomer a was Ph-CBSAm and the polymerization temperature was -40°C, the isotacticity of the product was 1 The H-NMR spectrum of atactic PNIPAM obtained by radical polymerization of N-isopropylacrylamide monomer was 1 The H-NMR spectrum is shown in Figure 10.

[0127] [Table 3]

[0128] R in monomer a as shown in Table 3 2 The isotacticity of the resulting PNIPAM increased in the order of methyl, isopropyl, and phenyl groups. Furthermore, for the same monomer a, the lower the polymerization temperature, the higher the isotacticity of the resulting PNIPAM. The combination of Ph-CBSAm and a polymerization temperature of -40°C achieved an isotacticity of 99%.

[0129] [Example 10: Library synthesis of isotactic acrylamide polymers from monomer a] In Example 10, Ph-CBSAm prepared in Synthesis Example 3 was polymerized to form polymer A, and the formed polymer A was subjected to an amine substitution reaction with various amines to form polymer B, an acrylamide polymer. However, the polymerization temperature for monomer a was set to −40° C.

[0130] Under dry argon, Ph-CBSAm (3.28 g, 10.0 mmol) prepared in Synthesis Example 3, AIBN (32.8 mg, 0.2 mmol), 97.0 mL of (CHCl) as a polymerization solvent, and a small amount of tetralin as an internal standard were added to a Schlenk tube in this order at room temperature to obtain a polymerization solution with the following concentration: [Ph-CBSAm] / [AIBN] = 100 / 2 (mmol / L). Next, the Schlenk tube was immersed in cooled methanol at -40 °C and irradiated with UV light from a UV LED lamp (CCS, LDL-71X12UV3-365-N, λ = 365 nm, 7.6 W) placed approximately 10 cm away from the Schlenk tube. Polymerization was initiated by UV irradiation. UV irradiation was continued at -40 °C for 24 hours. After the irradiation was stopped, the polymerized solution was stored at -20°C, and a portion of it was subjected to the amine substitution reaction shown below. Judging from the type of monomer a and the polymerization conditions, the isotacticity of polymer A formed by the above polymerization was considered to be 99% (see Table 3).

[0131] (Amine substitution reaction) The procedure for the amine substitution reaction was varied depending on the nucleophilicity and type of amine, as this would affect the solubility of the final polymer.

[0132] I: Method A Method A was used to form the acrylamide polymers shown below. From the left in the first row, N-isopropylacrylamide polymer (PNIPAM), N-(n-hexyl)acrylamide polymer, N-(n-octyl)acrylamide polymer, and N-(2-ethylhexyl)acrylamide polymer are listed. From the left in the second row, N-cyclobutylacrylamide polymer, N-cyclopentylacrylamide polymer, N-cyclohexylacrylamide polymer, N-cycloheptylacrylamide polymer, and N-(cyclooctyl)acrylamide polymer are listed. From the left in the third row, N-benzylacrylamide polymer and N-naphthylmethylacrylamide polymer are listed. [ka]

[0133] In Method A, 5.0 mL of the polymerization solution prepared above was transferred to a new glass tube. The resulting mixture was then evaporated under reduced pressure, followed by the addition of 5.0 mL of anhydrous THF. Next, various amines (5.0 mmol) were slowly added, and the resulting mixture was immersed in an oil bath at 60°C and stirred for 24 hours. The stirred solution was purified by precipitation into methanol, further washed with methanol, and dried under vacuum. As described above, the acrylamide polymer corresponding to the added amine was obtained as the product.

[0134] II: Method B Method B was used to form the acrylamide polymers shown below. From the left in the first row, there are N-ethylacrylamide polymer, N-(n-propyl)acrylamide polymer, N-(n-butyl)acrylamide polymer, and N-allylacrylamide polymer. From the left in the second row, there are N-(N,N-dimethylethyl)acrylamide polymer, N-[(2-methoxy)ethyl]acrylamide polymer, and N-(ethylimidazole)acrylamide polymer. [ka]

[0135] Method B was carried out in the same manner as Method A, except that purification by methanol dialysis was carried out instead of precipitation into methanol. During the methanol dialysis, the mixture was stirred for 4 hours or more and the solvent was replaced three times.

[0136] III: Method C Method C was used to form the N-(2-hydroxyethyl)acrylamide polymer shown below. Method C was identical to Method A, except that the amine substitution reaction was carried out in DMSO at 60°C and purification by methanol dialysis was performed. [ka]

[0137] IV: Method D Method D was used to form the N,N-diethylacrylamide polymer shown below. Method D was identical to Method A, except that the reaction time for the amine substitution reaction was 42 hours and purification by methanol dialysis was performed. [ka]

[0138] V: Method E Method E was used to form the N,N-di(n-butyl)acrylamide polymer shown below. Method E was performed identically to Method A, except the amine displacement reaction was carried out in 1,2-dimethoxyethane at 80° C. for 42 hours. [ka]

[0139] VI: Method F Method F was used to form the 4-acryloylmorpholine polymer shown below. Method F was performed identically to Method A, except the amine displacement reaction was carried out in 1,2-dimethoxyethane at 80° C. for 72 hours. [ka]

[0140] 1 The isotacticity of each product based on the H-NMR profile is shown in Table 4 below for those for which the value could be evaluated. Note that depending on the substituents that the acrylamide polymer product has on its side chain, the area of ​​the peak derived from the mesodiad may not be easily calculated due to overlap with the peak derived from the substituent. In other words, the isotacticity value may not be easily calculated. However, even for acrylamide polymers for which the isotacticity could not be calculated, the isotacticity value was compared with the corresponding atactic acrylamide polymer separately prepared by radical polymerization of acrylamide monomer. 1 The peaks in the H-NMR spectrum were sharp, which confirmed that the polymers had high stereoregularity. Furthermore, even those for which calculation was not possible were considered to have isotacticity comparable to that of polymer A and the acrylamide polymers for which calculation was possible.

[0141] Product 1 H-NMR measurements were carried out in DMSO-d6 at 150°C for polymers of each acrylamide, namely N-ethylacrylamide, N-(n-propyl)acrylamide, N-isopropylacrylamide, N-benzylacrylamide, N-naphthylmethylacrylamide, N-(N,N-dimethylethyl)acrylamide, N-allylamide, N-(2-hydroxyethyl)acrylamide, N-[(2-methoxy)ethyl]acrylamide, and N-(ethylimidazole)acrylamide. Polymerization of acrylamides such as N-(n-butyl)acrylamide, N-(N-hexylacrylamide), N-(n-octyl)acrylamide, N-(2-ethylhexylacrylamide), N-cyclobutylacrylamide, N-cyclopentylacrylamide, N-cyclohexylacrylamide, N-cycloheptylacrylamide, N-cyclooctylacrylamide, N,N-di(n-butyl)acrylamide, and 4-acryloylmorpholine was carried out in (CDCl) at 130 °C. Polymerization of N,N-diethylacrylamide was carried out in CDOD at room temperature. Polymerization of other acrylamides was carried out in CDCl at room temperature.

[0142] [Table 4]

[0143] As shown in Table 4, the isotacticity of polymer A used for amine substitution was largely maintained, confirming that it is possible to synthesize a library of acrylamide polymers exhibiting an isotacticity of 98% or more.

[0144] [Physical property evaluation] The physical properties of each acrylamide polymer synthesized in the library in Example 10 were evaluated, including crystallinity, glass transition temperature (Tg), and solubility in water.

[0145] (crystalline) The effect of the carbon number of the linear alkyl group on the crystallinity of isotactic acrylamide polymers into which linear alkyl groups had been introduced via the above-mentioned amine substitution was evaluated. The evaluation was carried out by differential scanning calorimetry (DSC) of the polymers. When an endothermic peak due to crystallization was observed on the DSC curve, the polymer was judged to be crystalline; when not, the polymer was judged to be non-crystalline. The crystallinity of the corresponding atactic acrylamide polymer was also evaluated for comparison.

[0146] It was confirmed that acrylamide polymers with an isotacticity of 98% or higher exhibit crystallinity different from that of atactic acrylamide. DSC confirmed that crystallinity was observed when the linear alkyl group had three or more carbon atoms. On the other hand, atactic acrylamide polymers did not exhibit crystallinity regardless of the carbon number (see Figure 11). Furthermore, it was confirmed that an acrylamide polymer (considered to have an isotacticity of approximately 95%) obtained by similar amine substitution on polymer A with an isotacticity of 95% prepared in Example 9 exhibited crystallinity when the linear alkyl group had eight or more carbon atoms. The above evaluation revealed that as the isotacticity increased, crystallinity tended to develop even when the linear alkyl group had a small carbon number. The improved crystallinity may be due to the increased likelihood of alkyl chain stacking between side chains in acrylamide polymers with high isotacticity.

[0147] (Tg) The Tg of the isotactic acrylamide polymer prepared by the above amine substitution was evaluated by DSC. The Tg was determined by the temperature shift of the baseline observed on the DSC curve. The Tg of the corresponding atactic acrylamide polymer was also evaluated for comparison.

[0148] For N-isopropylacrylamide polymer (PNIPAM), the Tg of a 99% isotactic polymer was 123.2°C, while the Tg of an atactic polymer was 130.1°C. It was confirmed that the isotactic polymer exhibited a lower Tg. In other words, the introduction of isotacticity decreased the Tg. The molecular weight of isotactic PNIPAM could not be measured due to its low solubility in DMF and THF. However, the molecular weight of isotactic N-benzyl acrylamide polymer, which was soluble in THF, was the same before and after amine substitution, suggesting that the decrease in Tg was not due to a decrease in molecular weight of PNIPAM. The decrease in Tg may be due to weakening of intermolecular interactions caused by the formation of a helical structure in the isotactic acrylamide polymer. The formation of a helical structure may also contribute to the increased likelihood of alkyl chain stacking. The decrease in Tg due to the formation of a helical structure is well known for isotactic methyl methacrylate polymers.

[0149] Furthermore, we compared the Tg of several acrylamide polymers other than PNIPAM between those with 99% isotacticity and those with atacticity. The DSC curves and Tg of each acrylamide polymer are shown in Figures 12A and 12B. As shown in Figures 12A and 12B, a decrease in Tg due to the introduction of isotacticity was confirmed for polymers of PNIPAM, N-(2-ethylhexyl)acrylamide, N-cyclopentylacrylamide, N-cyclohexylacrylamide, N-benzylacrylamide, N-cycloheptylacrylamide, and N-cyclooctylacrylamide. In particular, the Tg of N-benzylacrylamide polymer decreased by as much as 21°C. On the other hand, the decrease in Tg of N-naphthylmethylacrylamide polymer was small. This small decrease may be due to the inhibition of helical structure formation by bulky side chains or π-π stacking interactions in the naphthalene structure. Furthermore, it was confirmed that the number of carbon atoms in the cyclic alkyl group affects the amount of decrease in Tg due to the introduction of isotacticity in acrylamide polymers. Furthermore, in N-(2-ethylhexyl)acrylamide polymers with an isotacticity of 99%, a decrease in Tg of nearly 32°C was confirmed compared to atactic polymers, and an endothermic peak due to crystallization, which is not observed in atactic polymers, was observed in the DSC curve.

[0150] (Solubility in water) The water solubility of several isotactic acrylamide polymers prepared by the above amine substitutions and the corresponding atactic polymers was evaluated.

[0151] It has been known that atactic N-ethylacrylamide polymers and PNIPAM polymers formed by conventional radical polymerization are water-soluble. However, PNIPAM polymers with an isotacticity of 95% and 99% were insoluble in water. Furthermore, N-ethylacrylamide polymers, N-[(2-methoxy)ethyl]acrylamide polymers, and 4-acryloylmorpholine polymers, which are water-soluble when atactic, were confirmed to be insoluble in water when the isotacticity was 99%. Furthermore, N-(N,N-dimethylethyl)acrylamide polymers and N-(2-hydroxyethyl)acrylamide polymers were confirmed to be water-soluble even at an isotacticity of 99%, but their 0.25 wt% aqueous solutions showed no temperature response (dissolving to give a clear solution at low temperatures but flocculating and becoming cloudy at high temperatures). Furthermore, it was confirmed that N,N-diethylacrylamide polymers exhibit water solubility and temperature responsiveness when the isotacticity is 99%, as well as a higher cloud point than when they are atactic, and a large hysteresis (the difference in cloud point between the heating and cooling processes becomes larger).

[0152] The above evaluation confirmed that the introduction of isotacticity can change the physical properties of polymers. [Industrial Applicability]

[0153] The polymer obtained by the production method of the present invention can be considered to be applicable to various uses by utilizing the physical properties based on its stereoregularity, such as improved crystallinity and lowered Tg compared to polymers without stereoregularity.< / nmr>

Claims

1. polymerizing a monomer a represented by the following formula (1) to form a polymer A; converting the polymer A into a polymer B different from the polymer A by an alcohol substitution reaction or an amine substitution reaction; A method for producing a polymer. 【Chemistry 1】 R in the formula (1) 1 is a hydrogen atom or a methyl group. 2 represents an alkyl group which may have a substituent, an aryl group which may have a substituent, or a hydrogen atom.

2. The R 2 The method for producing a polymer according to claim 1, wherein is an aliphatic alkyl group having 1 to 6 carbon atoms which may have a substituent, or a phenyl group which may have a substituent.

3. The R 2 The method for producing a polymer according to claim 1 , wherein is a phenyl group which may have a substituent.

4. The method for producing a polymer according to claim 1 , wherein the polymer A is formed by radically polymerizing the monomer a.

5. The method for producing a polymer according to claim 1 , wherein the polymerization of the monomer a is carried out at 30° C. or lower.

6. The method for producing a polymer according to claim 1 , wherein the polymer B is isotactic.

7. The method for producing a polymer according to claim 6, wherein the isotacticity of the polymer B is 95% or more.

8. The method for producing a polymer according to claim 1 , wherein the polymer B is a (meth)acrylate polymer or a (meth)acrylamide polymer.

9. The method for producing a polymer according to claim 1 , wherein the polymer B is composed of a structural unit represented by the following formula (3): 【Chemistry 2】 R in the formula (3) 1 is a hydrogen atom or a methyl group. 3 and R 4 are each independently a hydrogen atom, an optionally substituted alkyl group, an optionally substituted alkylamino group, an optionally substituted allyl group, an optionally substituted alkyl ether group, an optionally substituted hydroxyalkyl group, an optionally substituted carboxy group, or an optionally substituted ester group. 3 and R 4 may be connected to each other.

10. An isotactic polymer composed of structural units shown in the following formula (3). 【Transformation 3】 R in the formula (3) 1 is a hydrogen atom or a methyl group. 3 and R 4 are each independently a hydrogen atom, an optionally substituted alkyl group, an optionally substituted alkylamino group, an optionally substituted allyl group, an optionally substituted alkyl ether group, an optionally substituted hydroxyalkyl group, an optionally substituted carboxy group, or an optionally substituted ester group. 3 and R 4 may be connected to each other.

11. 11. The polymer of claim 10, wherein the isotacticity of the polymer is 95% or greater.

12. A method for producing a polymer, comprising polymerizing a monomer a shown in formula (1) below to form an isotactic polymer A. 【Chemistry 4】 R in the formula (1) 1 is a hydrogen atom or a methyl group. 2 represents an alkyl group which may have a substituent, an aryl group which may have a substituent, or a hydrogen atom.

13. The method for producing a polymer according to claim 12, wherein the isotacticity of the polymer A is 95% or more.

14. An isotactic polymer composed of structural units shown in the following formula (2). 【Transformation 5】 R in the formula (2) 1 is a hydrogen atom or a methyl group. 2 represents an alkyl group which may have a substituent, an aryl group which may have a substituent, or a hydrogen atom.

15. 15. The polymer of claim 14, wherein the isotacticity of the polymer is 95% or greater.

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