JP7720581B2 - Dual-end reactive polymers, polyacrylic polymers, crosslinked polyacrylic polymers, cyclic polymers, and cyclic graft polymers - Google Patents

Description

The present invention relates to a novel both-end reactive polymer, a polyacrylic polymer obtained by polymerizing the both-end reactive polymer, a crosslinked polyacrylic polymer obtained by crosslinking the polyacrylic polymer, a cyclic polymer obtained by intramolecularly cyclizing the both-end reactive polymer, and a cyclic graft polymer obtained by polymerizing the cyclic polymer.

Acyl cations prepared from carboxylic acid halides and silver salts of superacids function as cationic polymerization initiators.

For example, Non-Patent Document 1 describes the synthesis of polytetrahydrofuran having methacryloyl groups at its terminals using a cationic polymerization initiator prepared from methacrylic acid chloride and silver hexafluoroantimony.

Allyl cations prepared from allyl halides and silver salts of superacids also function as cationic polymerization initiators.

For example, Non-Patent Document 2 describes the synthesis of polytetrahydrofuran using a cationic polymerization initiator prepared from allyl halide and silver hexafluorophosphate.

However, the cationic polymerization initiators described in Non-Patent Documents 1 and 2 cannot be used to synthesize polymers having reactive functional groups at their ends that are capable of substitution and addition reactions.

These polymers are extremely useful when modifying the polymer chains onto the surfaces of various materials or onto drugs such as proteins, or when linking different or identical polymer chains to synthesize polymers with higher structures such as block copolymers, graft copolymers, and star polymers.

The present inventors have previously provided a cationic polymerization initiator represented by the following general formula (A) for synthesizing a polymer having a reactive functional group capable of undergoing a substitution reaction and an addition reaction at its terminal (terminally reactive polymer) (unpublished at the time of filing this application).
(In the formula, R ¹ , R ² and R ³ each independently represent a hydrogen atom or a non-nucleophilic organic group, X ¹ represents a halogen atom, and Y ⁻ represents a counter anion.)

J. S. Vargas, J. G. Zilliox, P. Rempp, E. Franta, Polymer Bulletin, 1980, 3, 83 F. J. Burgess, A. V. Cunliffe, D. H. Richards, D. Thompson, Polymer, 1978, 19, 334

The present invention aims to provide novel both-end reactive polymers, polyacrylic polymers obtained by polymerizing the both-end reactive polymers, crosslinked polyacrylic polymers obtained by crosslinking the polyacrylic polymers, cyclic polymers obtained by intramolecularly cyclizing the both-end reactive polymers, and cyclic graft polymers obtained by polymerizing the cyclic polymers, all of which are obtained using the cationic polymerization initiator.

That is, the present invention relates to a polymer having reactive ends represented by the following general formula (1):
(In the formula, R ¹ , R ² and R ³ each independently represent a hydrogen atom or a non-nucleophilic organic group, X ¹ represents a halogen atom, R ⁴ represents a polymer segment, and R ⁵ represents an organic group having a functional group bonded to a terminal atom of the polymer segment and an active hydrogen-containing functional group.)

In the above general formula (1), ^R5 is preferably an organic group represented by the following general formula (2).
(In the formula, ^R6 is a single bond, a linear or branched aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a bridged ring hydrocarbon group, a spiro hydrocarbon group, or a functional group in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms.)

The present invention also relates to a polyacrylic polymer having a repeating unit represented by the following general formula (3):
(In the formula, R ¹ , R ² and R ³ each independently represent a hydrogen atom or a non-nucleophilic organic group; R ⁴ represents a polymer segment; R ⁷ represents an organic group having a functional group bonded to a terminal atom of the polymer segment and a functional group obtained by removing one active hydrogen from an active hydrogen-containing functional group; and m represents an integer of 1 or greater.)

In the above general formula (3), ^R7 is preferably an organic group represented by the following general formula (4).
(In the formula, ^R6 is a single bond, a linear or branched aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a bridged ring hydrocarbon group, a spiro hydrocarbon group, or a functional group in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms.)

The present invention also relates to a crosslinked polyacrylic polymer obtained by crosslinking the polyacrylic polymer.

The present invention also relates to a cyclic polymer represented by the following general formula (5):
(In the formula, R ¹ , R ² and R ³ each independently represent a hydrogen atom or a non-nucleophilic organic group, R ⁴ represents a polymer segment, and R ⁷ represents an organic group having a functional group bonded to a terminal atom of the polymer segment and a functional group obtained by removing one active hydrogen from an active hydrogen-containing functional group.)

In the above general formula (5), ^R7 is preferably an organic group represented by the following general formula (4).
(In the formula, ^R6 is a single bond, a linear or branched aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a bridged ring hydrocarbon group, a spiro hydrocarbon group, or a functional group in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms.)

The present invention also relates to a cyclic graft polymer having a repeating unit represented by the following general formula (6):
(In the formula, R ¹ , R ² and R ³ each independently represent a hydrogen atom or a non-nucleophilic organic group; R ⁴ represents a polymer segment; R ⁷ represents an organic group having a functional group bonded to a terminal atom of the polymer segment and a functional group obtained by removing one active hydrogen from an active hydrogen-containing functional group; and n represents an integer of 1 or greater.)

In the above general formula (6), ^R7 is preferably an organic group represented by the following general formula (4).
(In the formula, ^R6 is a single bond, a linear or branched aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a bridged ring hydrocarbon group, a spiro hydrocarbon group, or a functional group in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms.)

The cationic polymerization initiator used in the present invention, represented by the general formula (A), contains an acyl cation capable of initiating polymerization and an active halogen atom at the allylic position. By polymerizing various monomers using the cationic polymerization initiator and introducing an organic group having one or more active hydrogen-containing functional groups at the terminal of the resulting polymer, a dual-end reactive polymer having an active halogen atom at the allylic position, a carbon-carbon double bond, and an active hydrogen-containing functional group can be efficiently produced with almost no by-products. The dual-end reactive polymer of the present invention is highly useful for modifying the polymer chains on the surfaces of various materials or on drugs such as proteins, or for synthesizing polymers with higher structures such as block copolymers, graft copolymers, star polymers, polyacrylic polymers, cyclic polymers, and cyclic graft polymers by linking different or identical polymer chains together or by polycondensation or intramolecular cyclization.

<Cationic Polymerization Initiator>
The cationic polymerization initiator used in the present invention is represented by the following general formula (A).
(In the formula, R ¹ , R ² and R ³ each independently represent a hydrogen atom or a non-nucleophilic organic group, X ¹ represents a halogen atom, and Y ⁻ represents a counter anion.)

The non-nucleophilic organic group may be any organic group that does not have nucleophilicity, and is not otherwise particularly limited. Examples include linear or branched aliphatic hydrocarbon groups, organic groups in which some of the carbon atoms constituting the aliphatic hydrocarbon group are substituted with heteroatoms, alicyclic hydrocarbon groups, organic groups in which some of the carbon atoms constituting the alicyclic hydrocarbon group are substituted with heteroatoms, aromatic hydrocarbon groups, and organic groups in which some of the carbon atoms constituting the aromatic hydrocarbon group are substituted with heteroatoms. Examples of heteroatoms include oxygen atoms, sulfur atoms, and nitrogen atoms. The hydrocarbon groups may also have various substituents.

X ¹ is a halogen atom, and from the viewpoints of reactivity, ease of production, and cost, is preferably a chlorine atom or a bromine atom, more preferably a chlorine atom.

The aforementioned Y 1 ⁻ is a counter anion, and the type thereof is not particularly limited.

The method for preparing the cationic polymerization initiator is not particularly limited, and it can be prepared, for example, by reacting a compound represented by the following general formula (B) with a metal salt of a super strong acid.
(In the formula, R ¹ , R ² and R ³ each independently represent a hydrogen atom or a non-nucleophilic organic group, and X ¹ and X ² each represent a halogen atom.)

The explanations regarding the non-nucleophilic organic group and ^X1 are the same as above. ^X2 is a halogen atom, and from the viewpoints of reactivity, ease of production, and cost, is preferably a chlorine atom or a bromine atom, more preferably a chlorine atom.

The metal salt of the superacid is not particularly limited, and examples of superacids include tetrafluoroboric acid, hexafluorophosphoric acid, hexafluoroniobic acid, hexafluorotantalic acid, hexafluoroarsenic acid, hexafluoroantimonic acid, trifluoromethanesulfonic acid, fluorosulfonic acid, and chlorosulfonic acid. Examples of metal salts include lithium salts, sodium salts, potassium salts, silver salts, and copper salts.

From the viewpoint of selectively generating acyl cations, the metal salt of a super strong acid is preferably a silver salt of a super strong acid, more preferably at least one selected from the group consisting of _CF3SO3Ag , _FSO3Ag , _ClSO3Ag , _AgPF6 , _AgBF4 , _AgNbF6 , _AgTaF6 , _{AgAsF6 , and AgSbF6} , and even more preferably _CF3SO3Ag .

From the viewpoint of selectively generating acyl cations, the amount of the metal salt of the super strong acid used is preferably 1.1 molar equivalents or more, more preferably 1.2 molar equivalents or more, and preferably 1.5 molar equivalents or less, more preferably 1.3 molar equivalents or less, relative to 1 molar equivalent of the compound represented by general formula (B) above.

<Polymer with reactive ends>
The both-ends reactive polymer of the present invention is represented by the following general formula (1).
(In the formula, R ¹ , R ² and R ³ each independently represent a hydrogen atom or a non-nucleophilic organic group, X ¹ represents a halogen atom, R ⁴ represents a polymer segment, and R ⁵ represents an organic group having a functional group bonded to a terminal atom of the polymer segment and an active hydrogen-containing functional group.)

The non-nucleophilic organic group and ^X1 are the same as those described above. ^R4 is a polymer segment obtained by polymerizing various monomers. ^R5 is an organic group having an active hydrogen-containing functional group that is introduced to the end of the polymer segment.

The monomer is not particularly limited, and examples include monomers having a carbon-carbon double bond such as vinyl sulfide, aromatic vinyl monomers, epoxy group-containing monomers, vinyl ethers, and ketene acetals; and cyclic monomers such as cyclic ethers, cyclic sulfides, cyclic (tertiary) amines, cyclic phosphate esters, cyclic phosphites, cyclic sulfones, cyclic sulfonates, lactones, lactams, thiolactones, thiolactams, and cyclic acetals. These may be used alone or in combination of two or more. Of these, it is preferable to use cyclic monomers.

Examples of the vinyl sulfide include methyl vinyl sulfide, ethyl vinyl sulfide, and phenyl vinyl sulfide.

Examples of the aromatic vinyl monomer include styrene, chlorostyrene, chloromethylstyrene, α-methylstyrene, and other substituted styrenes.

Examples of the epoxy group-containing monomer include glycidyl (meth)acrylate, methyl glycidyl (meth)acrylate, and allyl glycidyl ether.

Examples of the vinyl ether include methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether, and divinyl ether.

Examples of the ketene acetal include ketene dialkyl acetals such as ketene dimethyl acetal.

Examples of the cyclic ether include ethylene oxide, propylene oxide, oxetane, tetrahydrofuran, tetrahydropyran, 1,2-dioxane, and 1,4-dioxane.

Examples of the cyclic sulfides include ethylene sulfide, trimethylene sulfide, tetrahydrothiophene, and tetrahydrothiopyran.

Examples of the cyclic (tertiary) amine include N-methylethyleneimine, N-phenylethyleneimine, N-methylazetidine, N-phenylazetidine, N-methylpyrrolidine, N-phenylpyrrolidine, N-methylpiperidine, and N-phenylpiperidine.

Examples of the cyclic phosphate ester include methyl ethylene phosphate and ethyl ethylene phosphate.

Examples of the cyclic phosphite ester include 2-methyl-2-oxo-1,3,2-dioxaphospholane, 2-ethyl-2-oxo-1,3,2-dioxaphospholane, and 2-isopropyl-2-oxo-1,3,2-dioxaphospholane.

Examples of the cyclic sulfone include sulfolane and 1,1-dioxo-tetrahydrothiopyran.

Examples of the cyclic sulfonic acid ester include 1,3-propane sultone and 1,4-butane sultone.

Examples of the lactone include β-propiolactone, γ-butyrolactone, δ-valerolactone, and ε-caprolactone.

Examples of the lactam include β-propiolactam, γ-butyrolactam, δ-valerolactam, and ε-caprolactam.

Examples of the thiolactone include β-propiothiolactone, γ-butyrothiolactone, δ-valerothiolactone, and ε-caprothiolactone.

Examples of the thiolactam include β-propiothiolactam, γ-butyrothiolactam, δ-valerothiolactam, and ε-caprothiolactam.

Examples of the cyclic acetal include 1,3-dioxetane, 1,3-dioxolane, and 1,3-dioxane.

The organic compound used to introduce an organic group having an active hydrogen-containing functional group at the end of the polymer segment is an organic compound having a functional group that reacts with the terminal functional group of the polymer segment and an active hydrogen-containing functional group, but is not otherwise particularly limited. The organic compound may have one active hydrogen-containing functional group, or two or more active hydrogen-containing functional groups.

Examples of the organic compound include organic compounds having a nucleophilic functional group containing active hydrogen or an alkali metal that reacts with the terminal functional group of the polymer segment, and one or more active hydrogen-containing functional groups.

Examples of the nucleophilic functional group include a hydroxyl group, a methylol group, a mercapto group, a carboxyl group, an amino group, a carbamoyl group, and functional groups in which the active hydrogen of these groups has been substituted with an alkali metal.

Examples of the active hydrogen-containing functional group include a hydroxyl group, a methylol group, a mercapto group, an amino group, an ammonium group, a carboxy group, an acyl group, a cyanomethyl group (-CH ₂ -CN), a nitromethyl group (-CH ₂ -NO ₂ ), and a sulfonylmethyl group (-CH ₂ -SO ₂ -).

Examples of the parent organic compound include linear or branched aliphatic hydrocarbon groups, alicyclic hydrocarbon groups, bridged ring hydrocarbon groups, spiro hydrocarbon groups, aromatic hydrocarbon groups, and groups in which some of the carbon atoms constituting the hydrocarbon group have been substituted with heteroatoms (e.g., oxygen atoms, sulfur atoms, nitrogen atoms, etc.). The hydrocarbon group may also have various substituents.

The ^R5 is preferably an organic group represented by the following general formula (2).
(In the formula, ^R6 is a single bond, a linear or branched aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a bridged ring hydrocarbon group, a spiro hydrocarbon group, or a functional group in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms.)

^R6 is a single bond, a linear or branched aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a bridged ring hydrocarbon group, a spiro hydrocarbon group, or a functional group in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms, preferably a linear or branched aliphatic hydrocarbon group, an alicyclic hydrocarbon group, or an aromatic hydrocarbon group, and more preferably an aromatic hydrocarbon group. Examples of the aliphatic hydrocarbon group include linear or branched aliphatic hydrocarbon groups having 1 to 10 carbon atoms. Examples of the alicyclic hydrocarbon group include alicyclic hydrocarbon groups having 3 to 10 carbon atoms. Examples of the aromatic hydrocarbon group include phenyl groups, biphenyl groups, and fused polycyclic aromatic hydrocarbon groups. Examples of the bridged ring hydrocarbon group include bicyclic and tricyclic bridged ring hydrocarbon groups. Examples of the spiro hydrocarbon group include groups having two or more 3- to 8-membered ring hydrocarbon groups. The hydrocarbon groups and the like may also have various substituents.

The method for producing the dual-end reactive polymer is not particularly limited, and examples thereof include: 1) a method of first reacting a compound represented by the above general formula (B) with a metal salt of a super strong acid to prepare a cationic polymerization initiator, then mixing the prepared cationic polymerization initiator with the monomer to carry out a living cationic polymerization reaction, and then reacting the organic compound with the terminal functional groups (cationic species) of the resulting polymer; 2) a method of first mixing a metal salt of a super strong acid with the monomer, then mixing the resulting mixture with the compound represented by the above general formula (B) to generate a cationic polymerization initiator in the reaction system and carry out a living cationic polymerization reaction, and then reacting the organic compound with the terminal functional groups (cationic species) of the resulting polymer; and 3) a method of first mixing the monomer with the compound represented by the above general formula (B), then mixing the resulting mixture with a metal salt of a super strong acid to generate a cationic polymerization initiator in the reaction system and carry out a living cationic polymerization reaction, and then reacting the organic compound with the terminal functional groups (cationic species) of the resulting polymer. The resulting polymer may be a homopolymer, a block copolymer, or a random copolymer. An appropriate organic solvent may be used, if necessary, when carrying out the reaction. Among the above production methods, production method 2) is preferred from the viewpoints of ease of production and production efficiency. Furthermore, from the viewpoint of selectively generating acyl cations, it is preferable to mix the metal salt of a super strong acid with the compound represented by general formula (B) above for a short period of time.

<Polyacrylic polymer>
The polyacrylic polymer of the present invention has a repeating unit represented by the following general formula (3).
(In the formula, R ¹ , R ² and R ³ each independently represent a hydrogen atom or a non-nucleophilic organic group; R ⁴ represents a polymer segment; R ⁷ represents an organic group having a functional group bonded to a terminal atom of the polymer segment and a functional group obtained by removing one active hydrogen from an active hydrogen-containing functional group; and m represents an integer of 1 or greater.)

The explanations for R ¹ to R ⁴ are the same as those described above. R ⁷ is an organic group having a functional group bonded to a terminal atom of the polymer segment and a functional group obtained by removing one active hydrogen from the active hydrogen-containing functional group, and the functional group obtained by removing one active hydrogen from the active hydrogen-containing functional group is bonded to a carbon atom at the allylic position.

The organic compound for introducing ^R7 is an organic compound having a functional group reactive with the terminal functional group of the polymer segment and an active hydrogen-containing functional group, and is not otherwise particularly limited. The organic compound may have one active hydrogen-containing functional group or two or more active hydrogen-containing functional groups.

Examples of the organic compound include organic compounds having a nucleophilic functional group containing active hydrogen or an alkali metal that reacts with the terminal functional group of the polymer segment, and one or more active hydrogen-containing functional groups. The description of the organic compound is the same as above.

In the above general formula (3), ^R7 is preferably an organic group represented by the following general formula (4).
(In the formula, ^R6 is a single bond, a linear or branched aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a bridged ring hydrocarbon group, a spiro hydrocarbon group, or a functional group in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms.)

The explanation regarding ^R6 is the same as above.

The method for producing the polyacrylic polymer is not particularly limited, and examples include a method in which the polymer with reactive ends is dissolved in an organic solvent and polymerized in the presence of a base such as a tertiary amine, a tertiary phosphine, or an alkali metal alkoxide salt, or an appropriate catalyst.

The organic solvent is not particularly limited as long as it allows the reaction to proceed, and examples include halogenated solvents such as dichloromethane, 1,2-dichloroethane, chloroform, and carbon tetrachloride; aromatic hydrocarbon solvents such as benzene, toluene, and xylene; aliphatic hydrocarbon solvents such as pentane, hexane, heptane, and octane; tetrahydrofuran, acetonitrile, N,N-dimethylformamide, and mixed solvents thereof. While the amount of organic solvent used is not particularly limited, an amount that results in a concentration of the dual-end reactive polymer of 0.01 mol/L to 10 mol/L is preferred, and an amount that results in a concentration of the dual-end reactive polymer of 0.1 mol/L to 5 mol/L is particularly preferred.

The polyacrylic polymer may be a homopolymer, a block copolymer, or a random copolymer. The polyacrylic polymer may also have repeating units other than the repeating unit represented by general formula (3) above.

<Crosslinked polyacrylic polymer>
The crosslinked polyacrylic polymer of the present invention is obtained by directly crosslinking the polyacrylic polymers with each other, or by crosslinking the polyacrylic polymers via a crosslinking agent. The crosslinking agent is not particularly limited, and examples thereof include crosslinking agents having unsaturated double bonds, specifically (meth)acrylate crosslinking agents and vinyl crosslinking agents. The crosslinking reaction can be carried out using a general thermal polymerization initiator or photopolymerization initiator, if necessary.

<Cyclic polymer>
The cyclic polymer of the present invention is represented by the following general formula (5).
(In the formula, R ¹ , R ² and R ³ each independently represent a hydrogen atom or a non-nucleophilic organic group, R ⁴ represents a polymer segment, and R ⁷ represents an organic group having a functional group bonded to a terminal atom of the polymer segment and a functional group obtained by removing one active hydrogen from an active hydrogen-containing functional group.)

The explanations for R ¹ to R ⁴ and R ⁷ are the same as those given above.

In the above general formula (5), ^R7 is preferably an organic group represented by the following general formula (4).
(In the formula, ^R6 is a single bond, a linear or branched aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a bridged ring hydrocarbon group, a spiro hydrocarbon group, or a functional group in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms.)

The explanation regarding ^R6 is the same as above.

The method for producing the cyclic polymer is not particularly limited, and examples include a method in which the polymer with reactive ends is dissolved in an organic solvent and subjected to intramolecular cyclization in the presence of a base such as a tertiary amine, a tertiary phosphine, or an alkali metal alkoxide salt, or an appropriate catalyst.

The organic solvent is not particularly limited as long as the reaction proceeds, and examples thereof include halogenated solvents such as dichloromethane, 1,2-dichloroethane, chloroform, and carbon tetrachloride; aromatic hydrocarbon solvents such as benzene, toluene, and xylene; aliphatic hydrocarbon solvents such as pentane, hexane, heptane, and octane; tetrahydrofuran, acetonitrile, N,N-dimethylformamide, and mixed solvents thereof. The amount of the organic solvent used is not particularly limited, but an amount such that the concentration of the dual-end reactive polymer is 10 ^-6 mol/L to 10 ^-3 mol/L is preferred, and an amount such that the concentration of the dual-end reactive polymer is 10 ^-5 mol/L to 10 ^-4 mol/L is particularly preferred.

The cyclic polymer can also be produced under pseudo-dilution conditions in which the concentration of the both-end reactive polymer exceeds ¹⁰ mol. In this case, intramolecular cyclization proceeds at a high rate due to an irreversible reaction, making it easier to increase the concentration of the cyclic polymer product compared to the above-mentioned case. This allows subsequent purification, isolation, and other processes to be carried out efficiently, resulting in efficient production of the cyclic polymer. A specific example of a production method under pseudo-dilution conditions is a method in which an organic solution in which the both-end reactive polymer is dissolved is gradually added dropwise to a large amount of organic solution containing the base or a suitable catalyst. More specifically, a method in which an organic solution in which the both-end reactive polymer is dissolved (dropping solution) at a concentration of more than ¹⁰ mol is added dropwise to an organic solution in which the base or a suitable catalyst is dissolved (mother liquor) at an addition rate of 1 to 5 mL per hour is exemplified. Thus, under pseudo-dilution conditions, the concentration of the both-end reactive polymer in the dropping solution is high, but the dropping rate per unit time is slow, and the concentration of the raw material polymer in the mother liquor immediately after the dropping solution is added is low, resulting in rapid reaction. On the other hand, since the amount of the mother liquor itself can be reduced, the concentration of the cyclic polymer produced in the mother liquor can be increased.

<Cyclic graft polymer>
The cyclic graft polymer of the present invention is represented by the following general formula (6).
(In the formula, R ¹ , R ² and R ³ each independently represent a hydrogen atom or a non-nucleophilic organic group; R ⁴ represents a polymer segment; R ⁷ represents an organic group having a functional group bonded to a terminal atom of the polymer segment and a functional group obtained by removing one active hydrogen from an active hydrogen-containing functional group; and n represents an integer of 1 or greater.)

The explanations for R ¹ to R ⁴ and R ⁷ are the same as those given above.

In the above general formula (6), ^R7 is preferably an organic group represented by the following general formula (4).
(In the formula, ^R6 is a single bond, a linear or branched aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a bridged ring hydrocarbon group, a spiro hydrocarbon group, or a functional group in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms.)

The explanation regarding ^R6 is the same as above.

The method for producing the cyclic graft polymer is not particularly limited, and examples include a method in which the cyclic polymer is dissolved in an organic solvent and polymerized, if necessary, using a thermal polymerization initiator or a photopolymerization initiator.

The organic solvent is not particularly limited as long as it allows the reaction to proceed, and examples include halogenated solvents such as dichloromethane, 1,2-dichloroethane, chloroform, and carbon tetrachloride; aromatic hydrocarbon solvents such as benzene, toluene, and xylene; aliphatic hydrocarbon solvents such as pentane, hexane, heptane, and octane; tetrahydrofuran, acetonitrile, N,N-dimethylformamide, and mixed solvents thereof.

The cyclic graft polymer may be a homopolymer, a block copolymer, or a random copolymer. Furthermore, the cyclic graft polymer may have a repeating unit other than the repeating unit represented by general formula (6) above.

The present invention will be explained below using examples, but the present invention is not limited to these examples in any way.

[Evaluation method]
(IR spectrum)
Measurement was carried out by a single reflection total reflection measurement method using an infrared spectrophotometer ("Cary 630 FTIR Spectrophotometer" manufactured by Agilent Technologies, Inc.).

(NMR spectrum)
Measurement was carried out at 25° C. using a nuclear magnetic resonance (NMR) apparatus ("AVANCE NEO" manufactured by Bruker Corporation). Deuterated chloroform was used as the measurement solvent, and chemical shift values were calibrated with the signals of tetramethylsilane and the solvent.

(molecular weight)
The molecular weight (number average molecular weight Mn) and molecular weight dispersity D (Mw/Mn) of the polymer were measured by loading two size exclusion columns, "GPC HK-404L" (Showa Denko K.K.) heated to 40°C in series into an EXTREMA chromatograph (JASCO). Tetrahydrofuran (for high performance liquid chromatography, stabilizer-free, JASCO) was used as the eluent and flowed at 0.8 mL/min. The chromatogram was detected with an ultraviolet absorption spectrometer, "UV-4070" (detected at 254 nm, JASCO) and a differential refractometer (RI-4035, JASCO). The chromatogram was analyzed by using standard polystyrene (TSK Gel Oligomer Kit, JASCO, Mn: 1.03 × 10 ⁶ , 3.89 × 10 ⁵ , 1.82 × 10 ⁵ , 3.68 × 10 ⁴ , 1.63 × 10 ^{4 ).} , 5.32×10 ³ , 3.03×10 ³ , 8.73×10 ² ).

[Nitrogen gas]
A glass tube was filled with molecular sieves 4A (1/16, manufactured by Wako Pure Chemical Industries, Ltd.) and cooled to −78° C. in a dry ice/methanol bath. Nitrogen gas was flowed into the glass tube to remove moisture.

[Monomer/polymerization solvent]
Under a nitrogen stream, 5 g of benzophenone was dissolved in 500 mL of tetrahydrofuran (ultra-dehydrated, manufactured by Kanto Chemical Co., Ltd.) in a large test tube, and sodium (manufactured by Wako Pure Chemical Industries, Ltd.) cut into 1 mm cubes was added until the solution turned deep blue. After stirring overnight, the large test tube was attached to a vacuum manifold.
Immediately before polymerization, a small test tube was attached to the vacuum manifold. The vacuum manifold and small test tube were evacuated to 1 mmHg and dried by heating with a gas burner. After cooling, the small test tube was cooled to -78°C in a dry ice/methanol bath. In this state, the cock connecting the large test tube to the vacuum manifold was opened, and the previously dried tetrahydrofuran was boiled and condensed into the small test tube. When a predetermined amount of tetrahydrofuran required for polymerization had condensed, dry nitrogen gas was introduced. The small test tube was removed from the vacuum manifold and a three-way cock through which nitrogen was flowed was attached. The tetrahydrofuran used for polymerization was measured from the small test tube using a syringe.

Example 1
(Synthesis of Dual-End Reactive Polymer)
0.514 g (2.00 mmol) of silver trifluoromethanesulfonate was dissolved in 20 mL of previously vacuum-distilled tetrahydrofuran and cooled to 0°C to obtain a tetrahydrofuran solution. Then, 0.306 mL (2.20 mmol) of α-(chloromethyl)acrylic acid chloride was added all at once to the tetrahydrofuran solution, and the mixture was stirred for 15 minutes to carry out a polymerization reaction. The reaction was then terminated by adding a tetrahydrofuran (40 mL) solution containing 0.449 g (2.20 mmol) of potassium hydrogen phthalate and 0.793 g (3.00 mmol) of 18-crown-6-ether, and the resulting silver chloride was removed by filtration. The filtrate was concentrated, diluted with 10 mL of chloroform, and washed with 10 mL of water. The organic layer was dried over magnesium sulfate and then concentrated under vacuum to obtain 1.83 g of a polymer with reactive ends. The molecular weight of the obtained polymer was evaluated by size exclusion chromatography, and the number average molecular weight (Mn) was 1,670 and the molecular weight dispersity (D) was 1.50. The degree of polymerization (n) calculated from the integrated intensity ratio of the terminal vinylidene group signal to the tetramethylene glycol unit signal in ^{the 1} H NMR spectrum was 13, and the absolute number average molecular weight (Mn) was 1,206.
¹ H-NMR (400 MHz, 25°C, CDCl ₃ ) δ7.81-7.79 (m, 1H, aromatic ring), 7.1-7.68 (m, 1H, aromatic ring), 7.58-7.51 (m, 2H, aromatic ring), 6.38 (s, 1H, C H H = ), 5.97 (s, 1H, CH H =), 4.35 (t, J = 6.3Hz, 2H, CH ₂ OCO), 4.29 (s, 2H, allyl), 4.23 (t, J = 6.6Hz, 2H, COCH ₂ ), 3.49-3.40 (m, 52H, OCH ₂ ), 1.63-1.58 (m, 52H, CH ₂ ) ppm.

Example 2
The same method as in Example 1 was used to obtain 1.27 g of a polymer with reactive ends at both ends. The molecular weight of the obtained polymer was evaluated by size exclusion chromatography, and the number average molecular weight (Mn) was 5,250 and the molecular weight dispersity (D) was 1.28. The degree of polymerization (n) calculated from the integrated intensity ratio of the terminal vinylidene group signal and the tetramethylene glycol unit signal in the ¹ H NMR spectrum was 44, and the absolute number average molecular weight (Mn) was 3,441.
¹ H-NMR (400 MHz, 25°C, CDCl ₃ ) δ7.81-7.79 (m, 1H, aromatic ring), 7.1-7.68 (m, 1H, aromatic ring), 7.58-7.51 (m, 2H, aromatic ring), 6.38 (s, 1H, C H H =), 5.97 (s, 1H, CH H =), 4.35 (t, J = 6.3 Hz, 2H, CH ₂ OCO), 4.29 (s, 2H, allyl), 4.23 (t, J = 6.6 Hz, 2H, COCH ₂ ), 3.49-3.40 (m, 176H, OCH ₂ ), 1.63-1.58 (m, 176H, CH ₂ ) ppm.

Example 3
2.05 g of a polymer with reactive ends was obtained in the same manner as in Example 1, except that the polymerization reaction time was changed to 60 minutes. The molecular weight of the obtained polymer was evaluated by size exclusion chromatography, and the number average molecular weight (Mn) was 7,180 and the molecular weight dispersity (D) was 1.24. The degree of polymerization n calculated from the integrated intensity ratio of the signal of the terminal vinylidene group to the signal of the tetramethylene glycol unit in ^{the 1} H NMR spectrum was 60, and the absolute number average molecular weight (Mn) was 4,595.
¹ H-NMR (400 MHz, 25°C, CDCl ₃ ) δ7.81-7.79 (m, 1H, aromatic ring), 7.1-7.68 (m, 1H, aromatic ring), 7.58-7.51 (m, 2H, aromatic ring), 6.38 (s, 1H, C H H =), 5.97 (s, 1H, CH H =), 4.35 (t, J = 6.3 Hz, 2H, CH ₂ OCO), 4.29 (s, 2H, allyl), 4.23 (t, J = 6.6 Hz, 2H, COCH ₂ ), 3.49-3.40 (m, 240H, OCH ₂ ), 1.63-1.58 (m, 240H, CH ₂ ) ppm.

Example 4
(Synthesis of Polyacrylic Polymer)
200 mg (0.166 mmol) of the dual-end reactive polymer obtained in Example 1 was dissolved in 1 mL of tetrahydrofuran, and 27.6 μL (0.199 mmol) of triethylamine was added. The mixture was stirred under reflux for 18 hours. The reaction solution was concentrated, diluted with 10 mL of tetrahydrofuran, and washed with 10 mL of saturated saline. The aqueous layer was extracted twice with 5 mL of tetrahydrofuran. The organic layers were combined and concentrated under vacuum to obtain 0.143 g of a polyhydric acrylic polymer. The molecular weight of the obtained polymer was evaluated by size exclusion chromatography, and the number average molecular weight (Mn) was 4480 and the molecular weight dispersity (D) was 1.53.
¹ H-NMR (400 MHz, 25°C, CDCl ₃ ) δ7.82-7.68 (m, 2H, aromatic ring), 7.56-7.52 (m, 2H, aromatic ring), 6.40 (s, 1H, C H H=), 5.93 (s, 1H, CH H =), 4.30 (t, J = 6.3Hz, 2H, CH ₂ OCO), 4.21 (s, 2H, allyl), 4.23 (t, J = 6.6Hz, 2H, COCH ₂ ), 3.49-3.40 (m, 176H, OCH ₂ ), 1.63-1.58 (m, 176H, CH ₂ ) ppm.

Example 5
0.119 g of a polyhydric acrylic polymer was obtained in the same manner as in Example 4, except that the both-end-reactive polymer obtained in Example 2 was used and the reaction temperature was 25° C. The molecular weight of the obtained polymer was evaluated by size exclusion chromatography, and it was found that the number average molecular weight (Mn) was 16,880 and the molecular weight dispersity (D) was 1.78.
¹ H-NMR (400 MHz, 25°C, CDCl ₃ ) δ7.82-7.68 (m, 2H, aromatic ring), 7.56-7.52 (m, 2H, aromatic ring), 6.40 (s, 1H, C H H=), 5.93 (s, 1H, CH H =), 4.30 (t, J = 6.3 Hz, 2H, CH ₂ OCO), 4.21 (s, 2H, allyl), 4.23 (t, J = 6.6 Hz, 2H, COCH ₂ ), 3.49-3.40 (m, 52H, OCH ₂ ), 1.63-1.58 (m, 52H, CH ₂ ) ppm.

Example 6
0.129 g of a polyhydric acrylic polymer was obtained in the same manner as in Example 4, except that the both-end-reactive polymer obtained in Example 3 was used and the reaction temperature was 25° C. The molecular weight of the obtained polymer was evaluated by size exclusion chromatography, and it was found that the number average molecular weight (Mn) was 33,520 and the molecular weight dispersity (D) was 1.95.
¹ H-NMR (400 MHz, 25°C, CDCl ₃ ) δ7.82-7.68 (m, 2H, aromatic ring), 7.56-7.52 (m, 2H, aromatic ring), 6.40 (s, 1H, C H H=), 5.93 (s, 1H, CH H =), 4.30 (t, J = 6.3Hz, 2H, CH ₂ OCO), 4.21 (s, 2H, allyl), 4.23 (t, J = 6.6Hz, 2H, COCH ₂ ), 3.49-3.40 (m, 176H, OCH ₂ ), 1.63-1.58 (m, 176H, CH ₂ ) ppm.

Example 7
(Photocuring reaction of polyacrylic polymer)
34.2 mg of the polyhydric acrylic polymer obtained in Example 5, 466 mg (3.64 mmol) of n-butyl acrylate, and 0.0107 g of 2,2-dimethoxy-2-phenylacetophenone were mixed to prepare a homogeneous solution, which was then applied to a Teflon (registered trademark) petri dish and weighted down with a glass petri dish. The solution was then irradiated with ultraviolet light at a wavelength of 300 nm for 5 minutes to obtain a crosslinked polyhydric acrylic polymer film.

Example 8
(Synthesis of Cyclic Polymer 1)
49.4 mg (41.2 μmol) of the dual-end reactive polymer obtained in Example 1 was dissolved in 5 mL of acetonitrile. Using a syringe pump, this solution was added dropwise at a flow rate of 50 μL/min to 500 mL of acetonitrile containing 2.20 μL of triethylamine (total amount of solvent used in the reaction: 505 mL). The reaction was allowed to proceed at room temperature for 20 hours, and the solution was concentrated, diluted with 10 mL of tetrahydrofuran, and washed with 10 mL of saturated saline. 10 mL of tetrahydrofuran was added to the aqueous layer for further extraction, and the combined organic layer was washed with 10 mL of saturated saline. The organic layer was dried over magnesium sulfate, concentrated, and vacuum-dried to obtain 36.9 mg of a cyclic polymer.
¹ H-NMR (400 MHz, 25°C, CDCl ₃ ) δ7.82-7.68 (m, 2H, aromatic ring), 7.56-7.52 (m, 2H, aromatic ring), 6.40 (s, 1H, C H H=), 5.93 (s, 1H, CH H =), 4.30 (t, J = 6.3 Hz, 2H, CH ₂ OCO), 4.21 (s, 2H, allyl), 4.23 (t, J = 6.6 Hz, 2H, COCH ₂ ), 3.49-3.40 (m, 52H, OCH ₂ ), 1.63-1.58 (m, 52H, CH ₂ ) ppm.

Example 9
(Synthesis of Cyclic Polymer 2 (Pseudo-Dilution Conditions))
100 mg (29.0 μmol) of the dual-end reactive polymer obtained in Example 2 was dissolved in 13 mL of acetonitrile. Using a syringe pump, this solution was added dropwise at a flow rate of 2 mL/h to 107 mL of acetonitrile containing 4.40 μL of triethylamine (total amount of solvent used in the reaction: 120 mL). The reaction was allowed to proceed at room temperature for 14 hours, and the solution was concentrated, diluted with 10 mL of chloroform, and washed with 10 mL of distilled water. The organic layer was washed with 10 mL of distilled water. The organic layer was dried over magnesium sulfate, concentrated, and vacuum-dried to obtain 29.4 mg of a crude product containing a cyclic polymer.
¹ H-NMR (400 MHz, 25°C, CDCl ₃ ) δ7.82-7.68 (m, 2H, aromatic ring), 7.56-7.52 (m, 2H, aromatic ring), 6.40 (s, 1H, C H H=), 5.93 (s, 1H, CH H =), 4.30 (t, J = 6.3Hz, 2H, CH ₂ OCO), 4.21 (s, 2H, allyl), 4.23 (t, J = 6.6Hz, 2H, COCH ₂ ), 3.49-3.40 (m, 176H, OCH ₂ ), 1.63-1.58 (m, 176H, CH ₂ ) ppm.

Example 10
(Synthesis of Cyclic Graft Polymer)
14 mg of the cyclic polymer obtained in Example 8, 109 mg of styrene, and 11 mg of 2,2'-azobis(isobutyronitrile) (AIBN) were added to 0.64 mL of toluene, and the mixture was subjected to freeze-degassing three times, followed by a radical copolymerization reaction at 65°C for 24 hours. After the reaction, the reaction solution was concentrated, and the resulting concentrate was reprecipitated in methanol (30 mL) and centrifuged (300 rpm, 3 minutes) to recover the precipitate. The resulting precipitate was dried in vacuo to obtain 90.9 mg of a cyclic graft polymer. The molecular weight of the resulting cyclic graft polymer was evaluated by size exclusion chromatography, revealing a number average molecular weight (Mn) of 5,800 and a molecular weight dispersity (D) of 1.54.
¹ H-NMR (400 MHz, 25°C, CDCl ₃ ) δ7.23-6.20 (m, 268H, Ar), 4.28-3.86 (br, 4H, COOCH ₂ ), 3.34 (t, 72H), 2.65-0.50 (m, CH ₂ /CH/OCH ₂ , 237H) ppm.

Example 11
(Synthesis of polyacrylic polymers and photocuring reaction)
An experiment was conducted in the same manner as in Example 1, yielding 0.674 g of a dual-end reactive polymer with a number average molecular weight (Mn) of 1,135. 0.137 g of the resulting dual-end reactive polymer was dissolved in 1 mL of tetrahydrofuran, and 20.1 μL of triethylamine was added and reacted for 17 hours. The resulting reaction solution was concentrated and vacuum dried for 6 hours to obtain a polyacrylic polymer with a yield of 0.137 g and a number average molecular weight (Mn) of 9,800. 0.553 g of lauryl acrylate and 16.5 mg of 2,2-dimethoxy-2-phenylacetophenone were added to 0.137 g of the resulting polyacrylic polymer, and the mixture was irradiated with 365 nm UV for 1 hour. The resulting cured product was immersed in chloroform, and the swelling ratio was measured as the weight gain after 4 days, which was 588%. The swelling degree of the cured product when immersed in methanol was 71%, and the swelling degree of the cured product when immersed in N,N-dimethylformamide was 31%.

Example 12
(Synthesis of polyacrylic polymers and photocuring reaction)
An experiment was conducted in the same manner as in Example 1, except that the reaction time was changed to 25 minutes. A yield of 1.44 g of a dual-end reactive polymer with a number average molecular weight (Mn) of 2,288 was obtained. 0.648 g of the resulting dual-end reactive polymer was dissolved in 4 mL of tetrahydrofuran, and 47.1 μL of triethylamine was added and the reaction was carried out for 17 hours. The resulting reaction solution was concentrated and vacuum dried for 6 hours to obtain a polyacrylic polymer with a yield of 0.663 g and a number average molecular weight (Mn) of 42,500. 0.410 g of lauryl acrylate and 14.1 mg of 2,2-dimethoxy-2-phenylacetophenone were added to 0.206 g of the resulting polyacrylic polymer, and the mixture was irradiated with 365 nm UV for 1 hour. The resulting cured product was immersed in chloroform, and the swelling ratio was measured as the weight gain after 4 days, which was 676%. The swelling degree of the cured product when immersed in methanol was 99%, and the swelling degree of the cured product when immersed in N,N-dimethylformamide was 53%.

Example 13
(Synthesis of polyacrylic polymers and photocuring reaction)
An experiment was conducted in the same manner as in Example 1, except that the reaction time was changed to 60 minutes. A yield of 1.38 g of a dual-end reactive polymer with a number average molecular weight (Mn) of 4,956 was obtained. 0.300 g of the resulting dual-end reactive polymer was dissolved in 1 mL of tetrahydrofuran, and 10.2 μL of triethylamine was added and the reaction was carried out for 23 hours. The resulting reaction solution was concentrated and vacuum dried for 2 hours to obtain a polyacrylic polymer with a yield of 0.299 g and a number average molecular weight (Mn) of 142,100. 0.185 g of lauryl acrylate and 12.0 mg of 2,2-dimethoxy-2-phenylacetophenone were added to 0.200 g of the resulting polyacrylic polymer, and the mixture was irradiated with 365 nm UV for 1 hour. The resulting cured product was immersed in chloroform, and the swelling ratio was measured as the weight gain after 4 days, which was 746%. The swelling degree of the cured product when immersed in methanol was 116%, and the swelling degree of the cured product when immersed in N,N-dimethylformamide was 266%.

The dual-end reactive polymer of the present invention is extremely useful when modifying the polymer chains on the surfaces of various materials or on drugs such as proteins, or when synthesizing polymers with higher structures such as block copolymers, graft copolymers, star polymers, polyacrylic polymers, cyclic polymers, or cyclic graft polymers by linking different or identical polymer chains together or by polycondensation or intramolecular cyclization. Furthermore, the polyacrylic polymers, crosslinked polyacrylic polymers, cyclic polymers, and cyclic graft polymers of the present invention are useful as raw materials for adhesives, pressure-sensitive adhesives, elastomers, and resist materials.

Claims (5)

A polymer having reactive ends represented by the following general formula (1):
(In the formula, ^R1 , ^R2 , and ^R3 each independently represent a hydrogen atom or a non-nucleophilic organic group, ^X1 represents a halogen atom, ^R4 represents a polymer segment, and ^R5 represents an organic group represented by the following general formula (2).)
(In the formula, ^R6 is a single bond, a linear or branched aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a bridged ring hydrocarbon group, a spiro hydrocarbon group, or a functional group in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms.) A polyacrylic polymer having a repeating unit represented by the following general formula (3):
(In the formula, ^R1 , ^R2 , and ^R3 each independently represent a hydrogen atom or a non-nucleophilic organic group, ^R4 represents a polymer segment, ^R7 represents an organic group represented by the following general formula (4), and m represents an integer of 1 or greater.)
(In the formula, ^R6 is a single bond, a linear or branched aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a bridged ring hydrocarbon group, a spiro hydrocarbon group, or a functional group in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms.) A crosslinked polyacrylic polymer obtained by crosslinking the polyacrylic polymer described in claim 2. A cyclic polymer represented by the following general formula (5):
(In the formula, R ¹ , R ² and R ³ each independently represent a hydrogen atom or a non-nucleophilic organic group, R ⁴ represents a polymer segment, and R ⁷ represents an organic group represented by the following general formula (4) .)
(In the formula, R6 ^is a single bond, a linear or branched aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a bridged ring hydrocarbon group, a spiro hydrocarbon group, or a functional group in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms.) A cyclic graft polymer having a repeating unit represented by the following general formula (6):
(In the formula, ^R1 , ^R2 , and ^R3 each independently represent a hydrogen atom or a non-nucleophilic organic group, ^R4 represents a polymer segment, ^R7 represents an organic group represented by the following general formula (4) , and n represents an integer of 1 or greater.)
(In the formula, R6 ^is a single bond, a linear or branched aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a bridged ring hydrocarbon group, a spiro hydrocarbon group, or a functional group in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms.)