JP2023043784A - Furan acrylic acid ester polymer, production method therefor, and polymerizable monomer for use in producing said polymer and production method therefor - Google Patents

Abstract

To provide a polymer having transparency and high gas-barrier properties which is able to replace existing acrylic resins obtained from petrochemical-derived starting materials, using a biomass-derived starting material.SOLUTION: A furan-ring-containing acrylic acid ester monomer synthesized from a biomass-derived starting material is polymerized by a group transfer polymerization method.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present invention relates to a furanacrylate ester polymer, a method for producing the same, a polymerizable monomer used for producing the polymer, and a method for producing the same.

In recent years, in order to contribute to the reduction of carbon dioxide emissions, active efforts have been made to manufacture various chemical products from non-petroleum raw materials. One of the efforts to move away from petroleum raw materials is to switch from petrochemical raw materials to biomass raw materials. However, chemicals obtained from biomass feedstocks are significantly different from those obtained from petrochemical feedstocks. Therefore, it is not possible to directly replace various chemical processes from conventional petrochemical-derived raw materials with biomass raw materials. However, it is difficult to replace chemical products derived from petrochemical raw materials.

In 2004, the US DOE classified them into various platforms as key substances of biomass raw material-derived chemicals (Non-Patent Document 1). Among them are furfural with 5 carbon atoms and 5-hydroxymethyl-2-furfural with 6 carbon atoms. Since furfural is easily obtained as a stable liquid, it was used as a solvent and fuel in the past, and is also used for the refining of lubricating oils and bleaching agents. In addition, it is used as a herbicide, insecticide, etc., and is also used as a raw material for plastics after being converted into succinic acid, 1,4-butanediol, and the like. 5-Hydroxymethyl-2-furfural has a hydroxyl group and an aldehyde group, and it is also attracting attention as a polyethylene terephthalate (PET) substitute material as polyethylene furanate (PEF) having a furan ring via furandicarboxylic acid by oxidation. .
PEF is known to have a lower gas permeability than (PET) (Non-Patent Document 2, Non-Patent Document 3, pp. 7-11). Further, it is known that the oxygen permeability is greatly reduced only by blending PEF in order to improve the gas barrier properties (Patent Document 1).

On the other hand, highly transparent acrylic resins, typically polymethyl methacrylate (PMMA) produced by polymerizing methyl methacrylate, are used in materials such as automobile lenses and contact lenses due to their transparency. , tableware, lighting plates, aquarium plates, etc. Methyl methacrylate is obtained, for example, by esterifying methacrylic acid obtained by oxidation of isobutene (oxidation method). Isobutene is commonly obtained during petroleum refining.

On the other hand, as a method for polymerizing unsaturated carboxylic acid esters having a β-substituted group produced from biomass, in recent years, the group transfer polymerization method, in which the carbonyl group is silylated to increase the polymerization reactivity of the unsaturated bond, is used to produce biomass. It has become possible to polymerize the derived crotonic acid ester and cinnamic acid ester (Patent Document 2, Non-Patent Documents 4 to 6).

Japanese Patent Application Publication No. 2015-514151 JP 2021-70787 A

Top Value Added Chemicals from Biomass, DOE NREL, August 2004 Hokkaido University press release "Development of technology for mass synthesis of bioplastic raw materials" 2019/4/11 Chisato Hayashi 2019 Doctoral Thesis "Development of Bio-Based Materials Containing Bifuryl Skeleton"Gunma University Graduate School of Science and Engineering Macromolecules 2019,52,4052-4058 Macromolecules 2020,53,7759-7766 COMMUNICATIONS CHEMISTRY, (2019) 2:109, https://doi.org/10.1038/s42004-019-0215-3

In recent years, transparent acrylic resins such as polymethyl methacrylate (PMMA) have been widely used to prevent the spread of sudden viruses and to isolate people from each other, and the demand has increased rapidly. ing. As described above, PMMA produced from methyl methacrylate is made from isobutane, which is obtained during petroleum refining, as a raw material.
Further, gas barrier properties are required for the purpose of isolation, but PMMA has moderate gas permeability and does not have high gas barrier properties like polyamide.

Therefore, since it is known that a polymer having a furan ring has gas barrier properties (Non-Patent Documents 2 and 3), in order to increase the gas barrier properties of PMMA, another polymer having a furan ring with high gas barrier properties is used in PMMA. It is conceivable to blend the polymers of However, blend polymers impair the transparency of PMMA.

In addition, by synthesizing an acrylic acid ester monomer having a furan ring and polymerizing it, it may be possible to prepare a polymer as a new acrylic resin having transparency and gas barrier properties. Due to the conjugation effect and the high reactivity of the furan ring, it was not possible to prepare a polymer by the reaction only at the acrylate site in the usual radical polymerization.

The present invention has been made in view of such a situation, and has a transparency and a high gas barrier property that can be substituted for existing acrylic resins obtained from petrochemical-derived raw materials. The problem is to provide using

As a result of examining the above problems, the present inventors synthesized a monomer having an acrylic ester structure in which a furan ring is introduced at the β-position from a biomass-derived raw material, and polymerized using this to obtain a petrochemical-derived The present inventors have found that it is possible to provide a transparent polymer having a high gas barrier property that can be substituted for the acrylic resin obtained from the raw material of the above, and have completed the following invention.
[1] A polymer represented by the following general formula (I).

(wherein R ₁ is an optionally substituted methyl group, an ethyl group, an optionally branched propyl group, an optionally branched butyl group, an optionally branched pentyl group, a cyclopentyl group, an optionally branched hexyl group, a cyclohexyl group, or a phenyl group, and R ₂ is hydrogen, an optionally substituted methyl group, an ethyl group, or an optionally branched Any of a propyl group, an optionally branched butyl group, an optionally branched pentyl group, an optionally branched hexyl group, an optionally branched hexyl group, and a phenyl group.)
[2] A method for producing the polymer represented by the general formula (I),
A method for producing a polymer by polymerizing a monomer represented by the following general formula (II).

(In the formula, R ₁ and R ₂ represent the same as R ₁ and R ₂ described above.)
[3] The method for producing the polymer of [2] above, wherein the monomer is polymerized by a group transfer polymerization method.
[4] The method for producing a polymer according to [2] or [3], wherein the monomer is synthesized from biomass-derived raw materials.
[5] A monomer for producing the polymer represented by the general formula (I), which is a polymerizable monomer represented by the general formula (II).
[6] A method for producing the polymerizable monomer represented by the general formula (II), which is synthesized from biomass-derived raw materials.
[7] The method for producing a polymerizable monomer according to [6], wherein a compound represented by the following general formula (III) and malonic acid or acetic acid are used as the biomass-derived raw materials.

(In the formula, R ₂ represents the same as R ₂ above.)

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to produce a polymer with high transparency and high gas barrier properties, which can be substituted for existing acrylic resins, using raw materials derived from 100% biomass, and polymerizes the olefin part. Depending on the degree, the possibility of adjusting various physical properties can be expanded.

IR measurement diagram of the monomer according to Comparative Example 1 of the present invention IR measurement diagram of the monomer according to Comparative Example 2 of the present invention IR measurement diagram of the monomer according to Example 1 of the present invention IR measurement diagram of the monomer according to Example 2 of the present invention IR measurement diagram of the monomer according to Example 3 of the present invention IR measurement diagram of the monomer according to Example 4 of the present invention IR measurement diagram of the monomer according to Example 5 of the present invention IR measurement diagram of the monomer according to Example 6 of the present invention IR measurement diagram of the polymer according to Example 7 of the present invention IR measurement diagram of the polymer according to Example 8 of the present invention IR measurement diagram of the polymer according to Example 9 of the present invention IR measurement diagram of the polymer according to Example 10 of the present invention IR measurement diagram of the polymer according to Example 12 of the present invention

EMBODIMENT OF THE INVENTION Hereinafter, the form (henceforth "this embodiment") for implementing this invention is demonstrated in detail.

[Polymerizable Monomer]
As a polymerizable monomer for synthesizing the polymer according to the present embodiment, an acrylic acid ester having a furan ring represented by the following general formula (II) can be used.

(wherein R ₁ is an optionally substituted methyl group, an ethyl group, an optionally branched propyl group, an optionally branched butyl group, an optionally branched pentyl group, a cyclopentyl group, an optionally branched hexyl group, a cyclohexyl group, or a phenyl group, and R ₂ is hydrogen, an optionally substituted methyl group, an ethyl group, or an optionally branched Any of a propyl group, an optionally branched butyl group, an optionally branched pentyl group, an optionally branched hexyl group, an optionally branched hexyl group, and a phenyl group.)

The acrylic acid ester can be synthesized by reacting a compound represented by the following general formula (III) with a carboxylic acid such as malonic acid or acetic acid.

(R ₂ represents the same as in general formula (I).)
Examples of compounds represented by general formula (III) include furfural and 5-hydroxymethyl-2-furfural. These include various biomass raw materials having a skeleton of 6-carbon saccharides such as glucose and fructose, and 5-carbon saccharides such as xylose and arabinose; It is a basic material derived from biomass obtained from sometimes obtained waste sugar solution and sugar solution as a product. In addition, since malonic acid and acetic acid are also obtained from fruits and the like, the acrylic acid ester, which is a monomer for producing the polymer according to the present embodiment, can be synthesized using 100% biomass-derived raw materials. .

[Polymer] When the acrylic acid ester is polymerized by radical polymerization, which is a general polymerization method, in addition to the conjugation of the carboxylic acid and the unsaturated bond, the highly reactive furan ring causes the unsaturated bond to The conjugation of is widened. Therefore, homopolymerization at the C—C double bond site of olefin, which is a characteristic of acrylic resins, has been difficult.
Therefore, in the present embodiment, a group transfer polymerization method (see the above-mentioned Patent Document 2 and Non-Patent Documents 4 to 6) developed as a polymerization method for crotonic acid esters and cinnamic acid esters is adopted, and C- A polymer was prepared that was homopolymerized at the C double bond site.

[Group transfer polymerization method (hereinafter referred to as "GTP")]
GTP is a polymerization method characterized by using an initiator for silylating the carbonyl group of an acrylic acid ester-based monomer and an organic acid catalyst to increase the polymerization reactivity of unsaturated bonds.

In the GTP of the present embodiment, it is preferable to use a polymerization initiator represented by the following general formula (IV) from the viewpoint of reactivity.

(In formula (IV), R ₃ , R ₄ , R ₅ , R ₆ , R ₇ and R ₈ are the same or different and may contain 1 or 2 hydrogen atoms or oxygen atoms, carbon number represents 1 to 20 aliphatic, alicyclic or aromatic organic groups;

Specific examples of the polymerization initiator represented by the general formula (IV) include 1-methoxy-1-(triethylsiloxy)-1-propene, 1-methoxy-1-(triethylsiloxy)-2
-methyl-1-propene, 1-methoxy-1-(triallylsiloxy)-2-methyl-1-propene, 1-methoxy-1-(tricyclohexylmethylsiloxy)-2-methyl-1-propene, 1-methoxy-1-(triphenylsiloxy)-2-methyl-1-propene, 1-butoxy-1-(tribenzylsiloxy)-2-methyl-1-propene, 1-methoxy-1-(phenyl dimethylsiloxy)-2-methyl-1-propene, 1-methoxy-1-(t-butyldimethylsiloxy)-2-methyl-1-propene, 1-benzyloxy-1-(tributylsiloxy)-2-ethyl- 1-propene, 1-methoxy-1-(triisopropylsiloxy)-2-methyl-1-propene and the like.

The organic acid catalyst used in the GTP of the present embodiment is not particularly limited as long as it is an organic acid catalyst, and examples thereof include Lewis acid catalysts, Bronsted acid catalysts, and organic molecular catalyst acid catalysts. Among them, compounds represented by the following general formula (V) or (VI) are preferable.

(In formula (V), _R9 represents a substituted or unsubstituted aryl group. _Rf1 and _Rf2 represent perfluoroalkyl groups which may be the same or different.)

(In formula (VI), R ₁₀ represents a hydrogen atom, —OR ₉ , a linear or branched alkyl group having 1 to 12 carbon atoms, a cycloalkyl group, or a silyl group. R ₁₀ represents a hydrogen atom, a carbon represents a linear or branched alkyl group or cycloalkyl group of numbers 1 to 12. Rf ₃ and Rf ₄ represent the same or different perfluoroalkyl groups.)

Examples of compounds represented by the general formula (V) include phenylbis(triflyl)methane, 2-naphthylbis(triflyl)methane, 1-naphthylbis(triflyl)methane, 2,4,6-trimethylphenylbis(triflyl)methane, ) methane, 4-(trifluoromethyl)phenylbis(triflyl)methane, 3,5-bis(trifluoromethyl)phenylbis(triflyl)methane, pentafluorophenylbis(triflyl)methane, {4-(pentafluorophenyl )-2,3,5,6-tetrafluorophenyl}bis(triflyl)methane, among others, pentafluorophenylbis(triflyl)methane is preferred from the viewpoint of good raw material availability.

Examples of the compound represented by the general formula (VI) include bis(trifluoromethane)sulfonylimide, trimethylsilylbis(trifluoromethanesulfonyl)imide, triethylsilylbis(trifluoromethanesulfonyl)imide, triisopropylsilylbis(trifluoromethane) sulfonyl)imide, tert-butyldimethylsilylbis(trifluoromethanesulfonyl)imide, phenyldimethylsilylbis(trifluoromethanesulfonyl)imide, N-(trifluoromethanesulfonyl)nonafluorobutanesulfonylimide, N-trimethylsilyl-N-(trifluoro romethanesulfonyl)nonafluorobutanesulfonylimide, trimethylsilylbis(nonafluorobutanesulfonyl)imide and the like.

Moreover, in the above-mentioned group transfer polymerization, it is preferable to have a step of adding water, alcohol, or acid into the reaction system after the polymerization step to terminate the polymerization reaction. In group transfer polymerization, during polymerization, the main chain end of the polymer has a ketene silyl acetal structure or enolate anion structure containing the silyl group of the polymerization initiator, and water, alcohol, or acid is added to the reaction system. As a result, the polymerization reaction can be terminated by converting the ketenesilyl acetal or enolate anion at one end of the polymer to a carboxylic acid or ester.

Examples of the alcohol include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol and the like.
Examples of the acid include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid and phosphoric acid, and organic acids such as acetic acid and benzoic acid.

EXAMPLES The present invention will be specifically described below with reference to Examples, but the present invention is not limited to these.
In the following examples and comparative examples, various physical properties were measured as follows.

<Yield>
The yields of the obtained polymerizable monomer and polymer were calculated using the following formulas.
Yield (%) of polymerizable monomer = [number of moles of obtained compound/number of moles of raw material compound (smaller number in case of multiple)] × 100
Polymer yield (%) = [mass of obtained polymer/mass of starting polymerizable monomer] x 100

<Measurement of ¹ H-NMR, ¹³ C-NMR, and IR>
The resulting polymerizable monomer was identified by ¹ H-NMR, ¹³ C-NMR and IR measurements.
All of the obtained polymers are currently soluble in common solvents such as methanol, ethanol, dichloromethane, chloroform, ethyl acetate, tetrahydrofuran, toluene, dimethyl sulfoxide, dimethylformamide, hexafluoroisopropanol, and methyl isobutyl ketone. Since it was low, no clear spectrum was obtained by ¹ H-NMR measurement and ¹³ C-NMR measurement, so it was identified by IR measurement.

( ¹ H-NMR measurement conditions)
Device: ECX-400 manufactured by JEOL Ltd.
Measurement solvent: Deuterated chloroform, deuterated dimethylsulfoxide or deuterated tetrahydrofuran

( ¹³ C-NMR measurement conditions)
Device: ECX-400 manufactured by JEOL Ltd.
Measurement solvent: Deuterated chloroform, deuterated dimethylsulfoxide or deuterated tetrahydrofuran

(IR measurement conditions)
Equipment: SPirit manufactured by Shimadzu Corporation

<Number average molecular weight, weight average molecular weight, degree of dispersion>
The number-average molecular weight and weight-average molecular weight of the resulting polymer were determined by GPC (gel permeation chromatography) measurement under the following measurement conditions. The dispersity (Mw/Mn) was obtained by dividing the weight average molecular weight (Mw) by the number average molecular weight (Mn).
(GPC measurement conditions)
Apparatus: Chromatograph system manufactured by JASCO Corporation (DG-2080, PU-2085,
AS-2055 Plus, CO-2065 Plus, RI-2031 Plus)
Elution solvent: Tetrahydrofuran Standard material: Showa Denko standard polystyrene (SM-105)
Separation column: Column TSKgel SuperHZM-M manufactured by Tosoh Corporation

<TG-DTA (simultaneous thermogravimetric and differential thermal measurement)>
The glass transition point, melting point and thermal decomposition temperature of the obtained polymer were measured by TG-DTA (simultaneous thermogravimetry and differential thermal measurement) (device name: DTG-60 manufactured by Shimadzu Corporation).

[Synthesis of Monomer]
(Comparative Example 1) Synthesis of E-3-(2-furanyl)acrylic acid (2-furanacrylic acid)

Furfural (9.0 mL, 109.2 mmol), malonic acid (10.6 g, 102.0 mmol), 2 mL of piperidine, 30 mL of pyridine (Py.), and 20 mL of dimethylformamide (DMF) were added to a 100 mL eggplant flask, and the mixture was stirred at 50°C for 16 minutes. Stirred for hours. After that, the mixture was stirred at 100° C. for another 5 hours. After completion of the reaction time, the temperature was returned to room temperature, the solvent was removed by an evaporator, 20 mL of water and 10 mL of sulfuric acid were added, and the mixture was stirred at 60° C. for 16 hours. After that, the mixture was further stirred at 80° C. for 1 hour. After returning to room temperature, the precipitated solid was collected by Kiriyama filtration and washed with water about three times. The collected light brown powdery solid was dried at 60° C. for 2 hours under reduced pressure to give 2-furanacrylic acid, which is compound 1 according to Comparative Example 1, with a yield of 83% (11.75 g, 85.0 mmol). Obtained.

It should be noted that the fact that this powdery solid is 2-furanacrylic acid represented by the above formula 1 is based on the following ¹ H-NMR measurement results, ¹³ C-NMR measurement results, and IR measurement results shown in FIG. Confirmed by
^1H -NMR measurement results
^1H NMR (400MHz, _CD3OD )
δ 7.61 (d, J = 1.8 Hz, 1H), 7.42 (d, J = 15.6 Hz, 1H), 6.73 (d, J = 3.7 Hz,
1H), 6.53 (q, J = 1.8Hz, 1H), 6.23 (d, J = 15.6Hz, 1H)
^13C -NMR measurement results
^13C NMR
(101MHz, _CD3OD ) δ 170.3, 152.2, 146.4, 132.7, 116.6, 116.2, 113.4

(Comparative Example 2) Synthesis of E-3-(5-methyl-2-furanyl)acrylic acid (5-methyl-2-furanacrylic acid)

5-methyl-2-furfural (11.61 g, 105.4 mmol), malonic acid (9.58 g, 92.0 mmol), piperidine 2 mL, pyridine 20 mL and DMF 20 mL were added to a 50 mL test tube and stirred at 50° C. for 16 hours. . After that, the mixture was stirred at 100° C. for another 5 hours. After completion of the reaction time, the reaction solution was returned to room temperature, transferred to a 200 mL round-bottomed flask, and the solvent was removed with an evaporator. 20 mL of water was added, 10 mL of sulfuric acid was added, and the mixture was stirred at 60° C. for 16 hours. After that, the mixture was further stirred at 80° C. for 1 hour. The reaction solution was returned to room temperature, and the precipitated solid was collected by Kiriyama filtration and washed with water about three times. The collected brown powdery solid was dried at 60° C. for 3 hours under reduced pressure to obtain 5-methyl-2-furanacrylic acid, compound 2 according to Comparative Example 2, with a yield of 94% (13.16 g, 86 .5 mmol).

The fact that this powdery solid is 5-methyl-2-furan acrylic acid represented by formula 2 above is confirmed by the following ¹ H-NMR measurement results, ¹³ C-NMR measurement results, and the IR shown in FIG. This was confirmed by the measurement results.
^1H -NMR measurement results
^1H NMR
(400 MHz, _CD3OD ) δ 7.34 (d, J = 15.6 Hz, 1H), 6.61 (d, J = 3.2 Hz,
1H), 6.15-6.10 (m, 2H), 2.33 (s, 3H)
^13C -NMR measurement results
^13C NMR
(101 MHz, _CD3OD ) δ 170.7, 157.1, 150.8, 132.8, 118.0, 114.7, 109.9,
13.6

(Example 1) Synthesis of methyl-E-3-(2-furanyl)acrylate (methyl 2-furanacrylate)

Compound 1 (4.14 g, 30 mmol) obtained in Comparative Example 1 and 60 mL of methanol were added to a 200 mL eggplant flask and stirred at 60°C. 0.5 mL of sulfuric acid was added thereto, and the mixture was heated under reflux at 80° C. for 16 hours. The reaction solution was returned to room temperature, methanol was removed by an evaporator, a saturated _NaHCO3 aqueous solution was added, and extraction was performed with chloroform. The organic layer was washed with water and brine (high-concentration sodium chloride aqueous solution), and dehydrated by adding Na ₂ SO ₄ . After removing chloroform with an evaporator, a brown liquid was obtained. After frozen storage at -4°C for 1 hour, methyl 2-furanacrylate, compound 3a of Example 1, was obtained as a brown solid with a yield of 70% (3.19 g, 21 mmol).
It was confirmed by the following ¹ H-NMR measurement results, ¹³ C-NMR measurement results, and IR measurement results shown in FIG.
^1H -NMR measurement results
^1H NMR
(400 MHz, _CDCl3 ) δ 7.46-7.40 (m, 2H), 6.59 (d, J = 3.2 Hz, 1H), 6.45
(q, J = 1.8Hz, 1H), 6.30 (d, J = 16.0Hz, 1H), 3.76 (s, 3H)
^13C -NMR measurement results
^13C NMR
(101 MHz, _CDCl3 ) δ 167.4, 150.8, 144.7, 131.2, 115.4, 114.8, 112.2,
51.6

(Example 2) Synthesis of ethyl-E-3-(2-furanyl)acrylate (ethyl 2-furanacrylate)

Compound 1 (7.50 g, 54 mmol) obtained in Comparative Example 1 and 120 mL of ethanol were added to a 300 mL eggplant flask and stirred at 60°C. 1.0 mL of sulfuric acid was added thereto, and the mixture was heated under reflux at 95° C. for 15 hours. The reaction solution was returned to room temperature, ethanol was removed with an evaporator, saturated NaHCO ₃ aqueous solution was added, and extraction was performed with chloroform. The organic layer was washed with water, brine, added with Na ₂ SO ₄ and dried. After removing chloroform with an evaporator, a brown liquid was obtained. By purifying the product by silica gel column chromatography, ethyl 2-furanacrylate, compound 3b of Example 2, was obtained as a yellow liquid with a yield of 58% (5.17 g, 37.4 mmol).

It was confirmed from the following ¹ H-NMR measurement results, ¹³ C-NMR measurement results, and IR measurement results shown in FIG. 4 that this liquid was the compound represented by Formula 3b above.
^1H -NMR measurement results
^1H NMR
(400MHz, _CDCl3 ) δ 7.48-7.41 (m, 2H), 6.60 (d, J = 3.4 Hz, 1H), 6.46
(q, J = 1.6Hz, 1H), 6.31 (d, J = 15.4Hz, 1H), 4.24 (q, J = 7.2Hz, 2H), 1.32
(t, J = 7.1Hz, 3H)
^13C -NMR measurement results
^13C NMR
(101MHz, _CDCl3 ) δ 167.0, 150.9, 144.6, 130.9, 115.9, 114.6, 112.2,
60.4, 14.3

Example 3 Synthesis of isopropyl-E-3-(2-furanyl)acrylate (isopropyl 2-furanacrylate)

Compound 1 (4.14 g, 30 mmol) obtained in Comparative Example 1 and 60 mL of isopropanol were added to a 200 mL eggplant flask and stirred at 60°C. 0.5 mL of sulfuric acid was added thereto, and the mixture was heated under reflux at 100° C. for 17 hours. The reaction solution was returned to room temperature, isopropanol was removed with an evaporator, saturated NaHCO ₃ aqueous solution was added, and extraction was performed with chloroform. The organic layer was washed with water, brine, added with Na ₂ SO ₄ and dried. When chloroform was removed with an evaporator, isopropyl 2-furanacrylate, compound 3c of Example 3, was obtained as a brown liquid with a yield of 46% (2.50 g, 13.8 mmol).

It was confirmed by the following ¹ H-NMR measurement results, ¹³ C-NMR measurement results, and IR measurement results shown in FIG. 5 that this liquid is the compound represented by Formula 3c above.
^1H -NMR measurement results
^1H NMR
(400 MHz, _CDCl3 ) δ 7.45-7.37 (m, 2H), 6.58 (d, J = 3.2 Hz, 1H), 6.44
(q, J = 1.7Hz, 1H), 6.28 (d, J = 16.0Hz, 1H), 5.10 (t, J = 6.2Hz, 1H), 1.28
(d, J = 6.4Hz, 6H)
^13C -NMR measurement results
^13C NMR
(101 MHz, _CDCl3 ) δ 166.5, 151.0, 144.6, 130.7, 116.5, 114.4, 112.2,
67.7, 21.9

(Example 4) Synthesis of methyl-E-3-(5-methyl-2-furanyl)acrylate (methyl 5-methyl-2-furanacrylate)

Compound 2 (5-methyl-2-furanacrylic acid) (4.56 g, 30 mmol) obtained in Comparative Example 2 and 60 mL of methanol were added to a 200 mL eggplant flask and stirred at 60°C. 0.5 mL of sulfuric acid was added thereto, and the mixture was heated under reflux at 80° C. for 16 hours. The reaction solution was returned to room temperature, methanol was removed by an evaporator, a saturated _NaHCO3 aqueous solution was added, and extraction was performed with chloroform. _The organic layer was washed with water, brine and dried over _Na2SO4 . Removal of chloroform with an evaporator gave an orange liquid crude product. The crude product was purified by silica gel chromatography to give a yellow solid. As a result, methyl 5-methyl-2-furanacrylate, compound 4a of Example 4, was obtained as a yellow powdery solid with a yield of 86% (4.26 g, 25.7 mmol).

It was confirmed by the following ¹ H-NMR measurement results, ¹³ C-NMR measurement results, and IR measurement results shown in FIG. 6 that this solid was the compound represented by formula 4a above.
^1H -NMR measurement results
^1H NMR
(400 MHz, CDCl ₃ ) δ 7.26 (d, J = 15.6 Hz, 1H), 6.40 (d, J = 3.2 Hz,
1H), 6.12 (d, J = 15.6 Hz, 1H), 5.97-5.96 (m, 1H), 3.67 (s, 3H), 2.24 (s, 3H)
^13C -NMR measurement results
^13C NMR
(101 MHz, _CDCl3 ) δ 167.8, 155.5, 149.4, 131.3, 116.5, 113.5, 108.8,
51.5, 13.8

(Example 5) Synthesis of ethyl-E-3-(5-methyl-2-furanyl)acrylate (ethyl 5-methyl-2-furanacrylate)

5-Methyl-2-furanacrylic acid (4.57 g, 30 mmol), which is Compound 2 obtained in Comparative Example 2, and 60 mL of ethanol were added to a 200 mL eggplant flask and stirred at 60°C. 0.5 mL of sulfuric acid was added thereto, and the mixture was heated under reflux at 95° C. for 15 hours. The reaction solution was returned to room temperature, ethanol was removed with an evaporator, saturated NaHCO ₃ aqueous solution was added, and extraction was performed with chloroform. _The organic layer was washed with water, brine and dried over _Na2SO4 . Removal of chloroform with an evaporator gave an orange liquid crude product. The crude product was purified by silica gel chromatography to give the product as a yellow liquid. It became solid when stored in a freezer (-4°C), and then returned to liquid after being left at room temperature for a while. As a result, ethyl 5-methyl-2-furanacrylate, compound 4b of Example 5, was obtained as a yellow liquid with a yield of 74% (4.00 g, 22.2 mmol).

It was confirmed by the following ¹ H-NMR measurement results, ¹³ C-NMR measurement results, and IR measurement results shown in FIG. 7 that this liquid is the compound represented by the above formula 4b.
^1H -NMR measurement results
^1H NMR
(400 MHz, CDCl ₃ ) δ 7.35 (d, J = 15.6 Hz, 1H), 6.50 (d, J = 3.2 Hz,
1H), 6.23 (d, J = 15.6Hz, 1H), 6.07-6.06 (m, 1H), 4.23 (q, J = 7.0Hz, 2H),
2.34 (s, 3H), 1.31 (t, J = 7.1Hz, 3H)
^13C -NMR measurement results
^13C NMR
(101 MHz, _CDCl3 ) δ 167.3, 155.3, 149.5, 131.0, 116.3, 114.0, 108.7,
60.2, 14.3, 13.8

Example 6 Synthesis of isopropyl-E-3-(5-methyl-2-furanyl)acrylate (isopropyl 5-methyl-2-furanacrylate)

5-Methyl-2-furanacrylic acid (4.56 g, 30 mmol), which is Compound 2 obtained in Comparative Example 2, and 60 mL of isopropanol were added to a 200 mL eggplant flask and stirred at 60°C. 0.5 mL of sulfuric acid was added thereto, and the mixture was heated under reflux at 100° C. for 16 hours. The reaction solution was returned to room temperature, isopropanol was removed with an evaporator, saturated NaHCO ₃ aqueous solution was added, and extraction was performed with chloroform. _The organic layer was washed with water, brine and dried over _Na2SO4 . Removal of chloroform with an evaporator gave an orange liquid crude product. The crude product was purified by silica gel chromatography to give the product as a yellow liquid. It did not become solid even when stored in a freezer (-4°C). As a result, isopropyl 5-methyl-2-furanacrylate, compound 4c of Example 6, was obtained as a yellow liquid with a yield of 64% (3.70 g, 19.1 mmol).

It was confirmed from the following ¹ H-NMR measurement results, ¹³ C-NMR measurement results, and IR measurement results shown in FIG. 8 that this liquid was the compound represented by formula 4c above.
^1H -NMR measurement results
1H-NMR (400 MHz, _CDCl3 ) δ 7.26
(d, J = 15.6Hz, 1H), 6.41 (d, J = 3.2Hz, 1H), 6.14 (d, J = 15.6Hz, 1H), 5.99
(q, J = 1.4 Hz, 1H), 5.03 (h, J = 6.2 Hz, 1H), 2.26 (s, 3H), 1.21 (d, J = 6.4
Hz, 6H)
^13C -NMR measurement results
^13C NMR
(101 MHz, _CDCl3 ) δ 166.8, 155.2, 149.6, 130.8, 116.1, 114.6, 108.7,
67.4, 21.9, 13.8

[Synthesis of polymer]
(Comparative Example 3) GTP of 2-furanacrylic acid (group transfer polymerization)

2-furanacrylic acid (0.25 g, 1.81 mmol), which is compound 1 obtained in Comparative Example 1, and dimethylketenemethyltrimethylsilyl acetal (MTS) as an initiator (5. 2 mg, 0.03 mmol) and 5.5 mL of dichloromethane were added. A solution prepared by dissolving N-(trimethylsilyl)bis(trifluoromethanesulfonyl)imide (Tf2NTMS) (10.6 mg, 0.03 mmol) in 0.5 mL of dichloromethane as an organic acid catalyst was added thereto, and the mixture was kept at −35° C. for 6 days. After stirring, 10 mL of methanol was added. Removal of the solvent by evaporator gave a yellow liquid, starting material 1 was recovered. Therefore, the polymerization reaction for forming polymer 4 described above did not proceed.

(Example 7) GTP of methyl 2-furanacrylate)

Methyl 2-furanacrylate (0.99 g, 6.5 mmol), which is compound 3a obtained in Example 1, MTS (22.7 mg, 0.13 mmol), and 3 mL of dichloromethane are placed in a 30 mL Schlenk tube in a glove box. was added. A solution of Tf ₂ NTMS (46.0 mg, 0.13 mmol) dissolved in 1 mL of dichloromethane was added thereto. The reaction solution was stirred at −40° C. for 7 days and 5 mL of methanol was added to quench the reaction. A brown liquid crude product was obtained by removing the solvent with an evaporator. When dissolved in CH ₂ Cl ₂ , it became cloudy, and when methanol was added, a white to pale brown solid precipitated out, which was collected by Kiriyama filtration. The collected solid was dried to recover 73.9 mg of a pale brown powdery solid.

From the IR measurement results shown in FIG. 9, it was confirmed that the obtained powdery solid was the compound represented by the above formula 5a.

In addition, as a result of TG-DTA, a clear melting point derived from a monomer was not observed, and it was found to be a polymer containing no monomer. It turned out to be
(Example 8) GTP of ethyl 2-furanacrylate

Ethyl 2-furanacrylate (1.08 g, 6.5 mmol), which is compound 3b obtained in Example 2, MTS (22.7 mg, 0.13 mmol), and 3 mL of dichloromethane are placed in a 30 mL Schlenk tube in a glove box. was added. A solution of Tf ₂ NTMS (46.0 mg, 0.13 mmol) dissolved in 1 mL of dichloromethane was added thereto. The reaction solution was stirred at −40° C. for 7 days, and methanol was added to quench the reaction. The precipitated powdery solid was collected by Kiriyama filtration and washed several times with methanol. Then, it was thoroughly dried to obtain the desired polymer 5b with a yield of 34% (0.37 g).

Since no clear spectrum was obtained from the ¹ H-NMR measurement and ¹³ C-NMR measurement results, the polymer was identified by IR measurement, and from the IR measurement results shown in FIG. It was confirmed that the compound was

In addition, samples were taken at 1 day, 5 days, and 6 days after the reaction, and the number average molecular weight (Mn), weight average molecular weight (Mw), and dispersity (Mw/Mn) were measured by GPC. Table 1 shows the respective results obtained. As a result, it was found that the molecular weight distribution of the polymer of this example was slightly improved, although a dramatic increase in molecular weight was not observed after the reaction time of 5 days.

Furthermore, as a result of TG-DTA, no particular melting point derived from a clear monomer was observed, and it was confirmed that the polymer did not contain a monomer. was observed.

(Example 9) GTP of isopropyl 2-furanacrylate

In a glove box, a 30 mL Schlenk tube was charged with isopropyl 2-furanacrylate (1.10 g, 6.1 mmol), which is compound 3c obtained in Example 3, MTS (20.9 mg, 0.12 mmol), and 3 mL of dichloromethane. was added. A solution prepared by dissolving Tf ₂ NTMS (42.4 mg, 0.12 mmol) in 1 mL of dichloromethane was added thereto. The reaction solution was stirred at −40° C. for 7 days, and methanol was added to quench the reaction. The solvent was removed by an evaporator to obtain a sticky white liquid crude product. The solution was dissolved in as little CH ₂ Cl ₂ as possible, and methanol was gradually added to precipitate a white powdery fine solid, which was collected by Kiriyama filtration. After that, it was thoroughly dried to obtain the target polymer 5c with a yield of 9% (0.10 g).

Although ^{the 1} H-NMR measurement result did not give a sharp spectrum, it showed the spectrum of a polymer containing no monomer. Accordingly, the polymer was identified by IR measurement, and from the IR measurement results shown in FIG. 11, it was confirmed to be the compound represented by the above formula 5c.

As a result of TG-DTA, a clear glass transition point and melting point were not observed, and a thermal decomposition temperature was observed at 341°C.
From the above results, it is presumed that the polymerization progressed and the target polymer was obtained.

(Example 10) GTP of methyl 5-methyl-2-furanacrylate

Methyl 5-methyl-2-furanacrylate (1.0802 g, 6.5 mmol), which is compound 4a obtained in Example 4, and MTS (22.7 mg, 0.13 mmol) were added to a 30 mL Schlenk tube in a glove box. , and 3 mL of dichloromethane were added. A solution of Tf ₂ NTMS (46.0 mg, 0.13 mmol) dissolved in 1 mL of dichloromethane was added thereto. The reaction solution was stirred at −40° C. for 7 days, and methanol was added to quench the reaction. Removal of the solvent by evaporator gave the crude product as a yellow-brown crispy solid. It was dissolved in a small amount of dichloromethane, and a mixture of methanol and water was added to precipitate a brown sticky liquid. The supernatant was removed and only the precipitate was recovered. The collected precipitate was dried to give 0.79 g (72% yield) of the desired polymer 6a as a brown crisp solid.

In ¹ H-NMR measurement and ¹³ C-NMR measurement, it was not possible to obtain a clear signal due to the low solubility in the solvent, so identification of the polymer was performed by IR measurement, and the IR measurement results shown in FIG. From the results, it was confirmed that the compound was represented by 6a in the above formula.

In addition, samples were taken at the end of the reaction time of 4 days, 5 days, 6 days, and 7 days, and the number average molecular weight (Mn), weight average molecular weight (Mw), and dispersity (Mw/Mn) were measured by GPC. . Table 2 shows the respective results obtained. From this, it was found that the molecular weight gradually increased according to the number of days.

In addition, as a result of TG-DTA, no signal corresponding to the melting point of the monomer was found, so it was found to be a polymer containing no monomer. A decomposition temperature was observed.

(Example 11) GTP of ethyl 5-methyl-2-furanacrylate

Ethyl 5-methyl-2-furanacrylate (1.17 g, 6.5 mmol), which is compound 4b obtained in Example 5, and MTS (22.7 mg, 0.13 mmol) were placed in a 30 mL Schlenk tube in a glove box. , and 3 mL of dichloromethane were added. A solution of Tf ₂ NTMS (46.0 mg, 0.13 mmol) dissolved in 1 mL of dichloromethane was added thereto. The reaction solution was stirred at −40° C. for 7 days, and methanol was added to quench the reaction. Removal of the solvent with an evaporator gave a brown-orange sticky solid (crude product: 1.12 g).

¹ H-NMR measurement of the crude product purified from CH ₂ Cl ₂ and water/methanol mixed solution and washed with MeOH did not give a clear peak, but a mixture of monomer and polymer was identified. The spectrum shown was obtained.

In addition, samples were taken at the end of the reaction time of 4 days, 5 days, 6 days, and 7 days, and the number average molecular weight (Mn), weight average molecular weight (Mw), and dispersity (Mw/Mn) were measured by GPC. . Table 3 shows the respective results obtained. From this, it was found that the molecular weight increases by nearly 10,000 by extending the reaction days.

Example 12 GTP of Isopropyl 5-methyl-2-furanacrylate

5-Methyl-2-furanacrylate isopropyl (1.26 g, 6.5 mmol), which is compound 4c obtained in Example 6, and MTS (22.7 mg, 0.13 mmol) were placed in a 30 mL Schlenk tube in a glove box. , and 3 mL of dichloromethane were added. A solution of Tf ₂ NTMS (46.0 mg, 0.13 mmol) dissolved in 1 mL of dichloromethane was added thereto. The reaction solution was stirred at −40° C. for 7 days, and methanol was added to quench the reaction. A pale yellow powdery solid precipitated along with cloudiness, so the solid was collected by Kiriyama filtration. After that, the solid was thoroughly dried to obtain the target polymer 6c with a yield of 48% (0.61 g).

Since no clear peak was observed in ¹ H-NMR measurement and ¹³ C-NMR measurement, the polymer was identified by IR measurement, and the spectrum of the polymer was confirmed. , was confirmed to be the compound represented by 6c in the above formula.

Also, samples were taken at the end of the reaction time of 3 days, 4 days, and 7 days, and the number average molecular weight (Mn), weight average molecular weight (Mw), and dispersity (Mw/Mn) were measured by GPC. The obtained results are shown in Table 4 and FIG. It was expected that the molecular weight would increase by extending the reaction days, but the average molecular weight decreased instead.

Furthermore, as a result of TG-DTA, a clear melting point derived from a monomer was not observed, and it was found to be a polymer containing no monomer. It turned out to be

According to the present invention, it is possible to provide a novel resin with high transparency and high gas barrier properties that can be substituted for existing acrylic resins.
In addition, since the novel resin can be produced using raw materials derived from 100% biomass, carbon dioxide emissions can be reduced.
Furthermore, by applying GTP to a difficult-to-polymerize monomer having a furan ring, it is possible to expand the possibility of adjusting new physical properties.

Claims (7)

A polymer represented by the following general formula (I).

(wherein R ₁ is an optionally substituted methyl group, an ethyl group, an optionally branched propyl group, an optionally branched butyl group, an optionally branched pentyl group, a cyclopentyl group, an optionally branched hexyl group, a cyclohexyl group, or a phenyl group, and R ₂ is hydrogen, an optionally substituted methyl group, an ethyl group, or an optionally branched Any of a propyl group, an optionally branched butyl group, an optionally branched pentyl group, an optionally branched hexyl group, an optionally branched hexyl group, and a phenyl group.) A method for producing the polymer represented by the general formula (I),
A method for producing a polymer by polymerizing a monomer represented by the following general formula (II).

(In the formula, R ₁ and R ₂ represent the same as R ₁ and R ₂ described above.) 3. The method for producing a polymer according to claim 2, wherein the monomer is polymerized by a group transfer polymerization method. 4. The method for producing a polymer according to claim 2, wherein the monomer is synthesized from biomass-derived raw materials. A polymerizable monomer represented by the general formula (II), which is a monomer for producing the polymer represented by the general formula (I). A method for producing the polymerizable monomer represented by the general formula (II), which is synthesized from biomass-derived raw materials. 7. The method for producing a polymerizable monomer according to claim 6, wherein a compound represented by the following general formula (III) and malonic acid or acetic acid are used as the biomass-derived raw materials.

(In the formula, R ₂ represents the same as R ₂ above.)

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