WO2023068347A1

WO2023068347A1 - METHOD FOR PRODUCING β-METHYL-δ-VALEROLACTONE POLYMER

Info

Publication number: WO2023068347A1
Application number: PCT/JP2022/039198
Authority: WO
Inventors: 宗紀偉士大; 友紀佐野; 祐作穗坂
Original assignee: 株式会社クラレ
Priority date: 2021-10-22
Filing date: 2022-10-20
Publication date: 2023-04-27
Also published as: TW202328272A; JPWO2023068347A1

Abstract

A method for producing a β-methyl-δ-valerolactone polymer, including a step of: adding an end modifier in a reaction solution in which a β-methyl-δ-valerolactone, an alcohol compound or water, and a base catalyst have been reacted; and carrying out an end modifying reaction.

Description

Method for producing β-methyl-δ-valerolactone polymer

The present invention relates to a method for producing a β-methyl-δ-valerolactone polymer.

From the perspective of global environmental conservation, there is a demand in a wide range of fields to reduce the environmental impact of plastic materials used in products. It is known to use biodegradable aliphatic polyester as a plastic material in order to reduce environmental load. For example, Patent Document 1 discloses a heat-stable liquid alkyl-δ-valerolactone polymer and a method for producing the same. As the above production method, it is described that a hydroxyl group-containing polymer represented by a specific general formula is reacted with a cyclic ether represented by a specific general formula in the presence of an acidic catalyst.

JP-A-3-181516

In Reference Example 1 of Patent Document 1, a polymer (average molecular weight: 1, 700) have been disclosed. However, the above polymer has a problem that depolymerization occurs during terminal modification, resulting in a decrease in molecular weight. Thus, there is room for further investigation on the method for producing a terminal-modified β-methyl-δ-valerolactone-based polymer.

Therefore, the present invention provides a production method capable of producing a terminal-modified β-methyl-δ-valerolactone polymer without causing a decrease in molecular weight.

As a result of intensive studies to solve the above problems, the present inventors have conceived the following invention and found that the problems can be solved.
That is, the present invention is as follows.

[1] β-methyl-δ-valerolactone, an alcohol compound or water, and a base catalyst are reacted with each other, and a terminal modifier is added to the reaction mixture to carry out a terminal modification reaction. A method for producing a δ-valerolactone polymer.
[2] The production method according to [1] above, wherein a terminal modification reaction is performed at a reaction temperature of 20 to 80° C. after adding the terminal modifying agent.
[3] The production method according to [1] or [2] above, wherein 1.0 to 20.0 molar equivalents of a terminal modifier are added to the hydroxyl groups of the alcohol compound.
[4] The production method according to any one of [1] to [3] above, wherein the alcohol compound is at least one selected from the group consisting of monoalcohols and polyhydric alcohols.
[5] The production method according to any one of [1] to [4] above, wherein the terminal modifier is at least one selected from the group consisting of acid anhydrides and acid halides.
[6] The terminal modifier includes a linear or branched alkyl group having 1 to 20 carbon atoms, a linear or branched alkenyl group having 2 to 20 carbon atoms, an aryl group having 6 to 12 carbon atoms, and carbon The production method according to any one of [1] to [5] above, which has at least one selected from the group consisting of 7 to 12 arylalkyl groups.
[7] The production method according to any one of [1] to [6] above, wherein the β-methyl-δ-valerolactone polymer has a number average molecular weight of 1,000 or more and 100,000 or less. .

According to the present invention, it is possible to provide a production method capable of producing a terminal-modified β-methyl-δ-valerolactone-based polymer without causing a decrease in molecular weight.

An example of the embodiment of the present invention will be described below. However, the embodiments shown below are examples for embodying the technical idea of the present invention, and the present invention is not limited to the following description.
Also, preferred forms of embodiments are indicated herein, and combinations of two or more of the individual preferred forms are also preferred forms. When there are several numerical ranges for items indicated by numerical ranges, the lower and upper limits thereof can be selectively combined to form a preferred form.
In this specification, when a numerical range is described as "XX to YY", it means "XX or more and YY or less". References to "molecular weight" mean "number average molecular weight" unless otherwise specified.

<Method for producing β-methyl-δ-valerolactone polymer>
The method for producing the β-methyl-δ-valerolactone-based polymer (hereinafter sometimes simply referred to as “polymer”) of the present embodiment comprises mixing β-methyl-δ-valerolactone with an alcohol compound or water. , a step of adding a terminal modifying agent to the reaction solution reacted with the base catalyst to carry out a terminal modifying reaction (hereinafter also referred to as a “reaction step”).
The above production method is characterized by adding a terminal modifying agent directly to a reaction solution obtained by reacting β-methyl-δ-valerolactone, an alcohol compound or water, and a basic catalyst. That is, after the ring-opening polymerization of β-methyl-δ-valerolactone, a terminal modifier is added to the reactor in which the ring-opening polymerization was performed without removing the ring-opening polymer once, and the terminal of the ring-opening polymer is Denaturation can be performed. In the reaction step, since the ring-opening polymerization reaction and the terminal modification reaction are performed in one pot, the above production method can be said to be a simplified process, and an improvement in productivity can be expected.

Here, Reference Example 1 of Patent Document 1 describes that the molecular weight is reduced by terminal modification.
Usually, β-methyl-δ-valerolactone becomes a ring-opening polymer having terminal hydroxyl groups through a ring-opening polymerization reaction. Since the ring-opening polymer has a terminal hydroxyl group in this manner, depolymerization is likely to occur. Since terminal modification of the ring-opened polymer once taken out is carried out at a relatively high temperature (about 100°C), the rate of thermal decomposition tends to increase, and the ring-opened polymer undergoes depolymerization, resulting in a decrease in molecular weight. Conceivable.
On the other hand, according to the production method of the present embodiment, since the molecular weight does not decrease, it is possible to obtain a high-molecular-weight polymer even though the terminal is modified.

<Reaction process>
[Alcohol compound or water]
The alcohol compound that can be used in this embodiment is not particularly limited as long as the effects of the present invention can be obtained. An alcohol compound may be used individually by 1 type, and may use 2 or more types together.
Alcohol compounds include, for example, linear or branched aliphatic hydrocarbon alcohols having 1 to 20 carbon atoms, alcohols of aromatic hydrocarbons having 6 to 12 carbon atoms, and alkyl aromatic hydrocarbons having 7 to 12 carbon atoms. Alcohol etc. are mentioned. These alcohol compounds may have saturated or unsaturated hydrocarbon groups. In the case of the above-mentioned "alcohol of branched aliphatic hydrocarbon", the number of carbon atoms is 3-20.
From the viewpoint of ease of handling, alcohol compounds include alcohols of linear or branched aliphatic hydrocarbons having 1 to 16 carbon atoms, alcohols of aromatic hydrocarbons having 6 to 9 carbon atoms, and alkyl compounds having 7 to 10 carbon atoms. Aromatic hydrocarbon alcohols are preferred, linear or branched aliphatic hydrocarbon alcohols having 1 to 10 carbon atoms are more preferred, and linear or branched aliphatic hydrocarbon alcohols having 1 to 5 carbon atoms are preferred. There may be.
Also, the alcohol compound may be at least one selected from the group consisting of monoalcohols and polyhydric alcohols.

Examples of alcohol compounds include methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-octanol, 1-nonanol, 1-decanol, 1-undecanol, 1-dodecanol, 1 -tridecanol, 1-tetradecanol, 1-heptadecanol, 1-hexadecanol (cetanol), 1-heptadecanol, 1-octadecanol, 1-nonadecanol, 1-icosadecanol;
Ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,2-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octane Diol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,15-hepta decanediol, 1,16-hexadecanediol, 1,17-heptadecanediol, 1,18-octadecanediol, 1,19-nonadecanediol, 1,20-icosadecanediol;
isopropanol, 1-methylpropanol, 2-methylpropanol, t-butanol, 1,1-dimethylpropanol, 2,2-dimethylpropanol, 1,2-dimethylpropanol, 1-ethylpropanol, 2-ethylpropanol, 1,1 -diethylpropanol, 1-methylbutanol, 2-methylbutanol, 3-methylbutanol (isoamyl alcohol), 1,1-dimethylbutanol, 2,2-dimethylbutanol, 3,3-dimethylbutanol, 1,3,3- trimethylbutanol, 1-ethylbutanol, 2-ethylbutanol, 3,3-dimethylbutanol, 1-propylbutanol, 1-methylpentanol, 2-methylpentanol, 3-methylpentanol, 4-methylpentanol, 4 , 4-dimethylpentanol, 1-ethylpentanol, 2-ethylpentanol, 3-ethylpentanol, 4-ethylpentanol, 1-propylpentanol, 2-propylpentanol, 1-butylpentanol, 1 -methylhexanol, 2-methylhexanol, 3-methylhexanol, 4-methylhexanol, 5-methylhexanol, 5,5-dimethylhexanol, 1-ethylhexanol, 2-ethylhexanol, 3-ethylhexanol, 4-ethylhexanol , 1-propylhexanol, 2-propylhexanol, 3-propylhexanol, 1-butylhexanol, 2-butylhexanol, 1-methylhexanol, 2-methylhexanol, 3-methylheptanol, 4-methylheptanol, 5- methylheptanol, 6-methylheptanol, 6,6-dimethylheptanol, 1-ethylheptanol, 2-ethylheptanol, 3-ethylheptanol, 4-ethylheptanol, 5-ethylheptanol, 1- Propylheptanol, 2-propylheptanol, 3-propylheptanol, 1-methyloctinol, 2-methyloctinol, 3-methyloctinol, 4-methyloctinol, 5-methyloctinol, 6-methyloctinol Nol, 7-methyloctinol, 7,7-dimethyloctinol, 1-ethyloctinol, 2-ethyloctinol, 3-ethyloctinol, 4-ethyloctinol, 5-ethyloctinol, 6-ethyloctinol Nol, 1-methylnonanol, 2-methylnonanol, 3-methylnonanol, 4-methylnonanol, 5-methylnonanol, 6-methylnonanol, 7-methylnonanol, 8-methylnonanol, 3,5,5-trimethylhexanol;
propylene glycol, neopentyl glycol, pentaglycerol (trimethylolethane), pentaerythritol; and the like.

The water that can be used in this embodiment is not particularly limited as long as the effects of the present invention can be obtained. For example, tap water, distilled water, ion-exchanged water, industrial water, deionized water, etc. can be used, and from the viewpoint of reaction efficiency, yield, etc., distilled water and ion-exchanged water are preferred.

[Base catalyst]
Base catalysts that can be used in the present embodiment include metal catalysts such as alkali metals and alkali metal compounds, organic base compounds, and the like. The basic catalyst may be used alone or in combination of two or more.

Among alkali metals, lithium is preferred.
Examples of alkali metal compounds include organic alkali metal compounds, alkali metal hydroxide compounds, alkali metal hydride compounds, and the like.
As the organic alkali metal compound, an organic lithium compound is preferred.
Organic lithium compounds such as methyllithium, ethyllithium, propyllithium, isopropyllithium, n-butyllithium, sec-butyllithium, tert-butyllithium, tert-octyllithium, n-decyllithium, phenyllithium, 2-naphthyl Lithium, 2-butylphenyllithium, 4-phenylbutyllithium, cyclohexyllithium, cyclopentyllithium and the like.

Examples of alkali metal hydroxide compounds include sodium hydroxide, potassium hydroxide, cesium hydroxide, lithium hydroxide and the like.
Examples of alkali metal hydride compounds include sodium borohydride and the like.

Examples of organic base compounds include amine compounds having an amidine skeleton or a guanidine skeleton. Examples of amine compounds include 1,8-diazabicyclo[5.4.0]undecene-7 (DBU), 1,5-diazabicyclo[4.3.0]nonene-5 (DBN), guanidine, 1,1, 3,3-tetramethylguanidine (TMG), 1,5,7-triazabicyclo[4.4.0]decan-5-ene (TBD), 7-methyl-1,5,7-triazabicyclo[ 4.4.0] decan-5-ene (MTBD) and the like.

Metal catalysts such as organomagnesium compounds and organozinc compounds can also be used as basic catalysts.

In the reaction step, when alcohol is used, the base catalyst is preferably 0.005 to 1.5 molar equivalents, more preferably 0.007 to 1.2 molar equivalents, still more preferably 0.007, relative to the hydroxyl group of the alcohol compound. It is preferable to add up to 1.0 molar equivalents, more preferably 0.007 to 0.8 molar equivalents, and even more preferably 0.007 to 0.6 molar equivalents. When water is used, it is preferable to add a basic catalyst in an amount of preferably 0.005 to 3.0 molar equivalents, more preferably 0.1 to 1.5 molar equivalents, relative to water.

[β-methyl-δ-valerolactone]
As β-methyl-δ-valerolactone that can be used in this embodiment, one produced by a known method can be used. For example, it can be produced by a known method using 2-hydroxy-4-methyltetrahydropyran or the like as a raw material (JP-B-6-53691, etc.).
In addition, β-methyl-δ-valerolactone can be used as a commercial product, and can be used regardless of whether it is derived from petrochemicals or bio-derived.
In the reaction step, when alcohol is used, it is preferable to add β-methyl-δ-valerolactone in an amount of preferably 5 to 1,500 molar equivalents, more preferably 5 to 1,000 molar equivalents, relative to the hydroxyl group of the alcohol compound. . When water is used, it is preferable to add β-methyl-δ-valerolactone in an amount of preferably 5 to 1,500 molar equivalents, more preferably 5 to 1,000 molar equivalents, relative to water.

[Terminal modifier]
Terminal modifiers that can be used in this embodiment include acid anhydrides and acid halides (acid halides are also referred to as “halogenated esters”). Acid anhydrides and acid halides are not particularly limited as long as the effects of the present invention can be obtained.
In addition, terminal modifiers include, for example, linear or branched alkyl groups having 1 to 20 carbon atoms, linear or branched alkenyl groups having 2 to 20 carbon atoms, aryl groups having 6 to 12 carbon atoms, and carbon A terminal modifier having at least one group selected from the group consisting of 7 to 12 arylalkyl groups can be used. The terminal modifier contains at least one group selected from the group consisting of linear or branched alkyl groups having 1 to 20 carbon atoms, aryl groups having 6 to 12 carbon atoms, and arylalkyl groups having 7 to 12 carbon atoms. acid anhydrides and acid halides having The "branched alkyl group" has 3 to 20 carbon atoms, and the "branched alkenyl group" has 3 to 20 carbon atoms.
Among them, from the viewpoint of handleability, the terminal modifier is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, a linear or branched alkenyl group having 2 to 10 carbon atoms, or 6 to 9 carbon atoms. and an acid anhydride and acid halide having at least one group selected from the group consisting of an aryl group and an arylalkyl group having 7 to 10 carbon atoms, more preferably a linear or branched alkyl group having 1 to 5 carbon atoms They are acid anhydrides and acid halides having at least one group selected from the group consisting of groups.

Specific acid anhydrides include acetic anhydride, oxalic anhydride, propionic anhydride, succinic anhydride, maleic anhydride, benzoic anhydride, phthalic anhydride, glutaric anhydride, methacrylic anhydride, butyric anhydride, and isobutyric anhydride. , 1,8-naphthalic anhydride, trifluoroacetic anhydride, cyclohexanecarboxylic anhydride and the like.
Specific examples of acid halides include acetyl chloride, propionyl chloride, butyroyl chloride, trifluoroacetyl chloride, benzoyl chloride, 2-furoyl chloride, hexanoyl chloride, phenylacetyl chloride, acetyl bromide, propionyl bromide, and bromide. benzoyl and the like.
In the reaction step, when alcohol is used, a terminal modifier is preferably added in an amount of 1.0 to 20.0 molar equivalents, more preferably 1.0 to 10.0 molar equivalents, still more preferably 1 to the hydroxyl group of the alcohol compound. It is preferable to add 0.0 to 8.0 molar equivalents. When water is used, it is preferable to add a terminal modifier in an amount of preferably 1.0 to 20.0 molar equivalents, more preferably 1.0 to 10.0 molar equivalents, relative to water.

[Promoter]
A co-catalyst may be added in the reaction step, if necessary.
Examples of cocatalysts that can be used include amine compounds such as triethylamine, tributylamine, trioctylamine, imidazole, pyridine, aminopyridine and 4-dimethylaminopyridine.
When alcohol is used in the reaction step, a co-catalyst can be added in an amount of 0.001 to 10 molar equivalents relative to the hydroxyl group of the alcohol compound. Also, when water is used, the co-catalyst can be added in an amount of 0.001 to 10 molar equivalents relative to water.

[solvent]
The reaction step can be performed in the presence of a solvent inert to the ring-opening polymerization reaction. Examples of solvents include aliphatic hydrocarbons such as cyclohexane, methylcyclohexane, n-hexane and n-pentane; aromatic hydrocarbons such as benzene, toluene and xylene.

[Reaction conditions]
In the reaction step, the reaction temperature during the ring-opening polymerization reaction in which β-methyl-δ-valerolactone, an alcohol compound or water, and a basic catalyst are reacted is usually 20 to 100°C, preferably 20°C. ~80°C, more preferably 30-80°C. The reaction time is usually 1 minute to 24 hours.
In the reaction step, after adding the terminal modifying agent to the reaction solution, the reaction temperature at which the terminal modification reaction is carried out is usually 20 to 80°C, preferably 30 to 80°C, more preferably 50 to 80°C. is. The terminal modification reaction can proceed under relatively mild temperature conditions. The reaction time is usually 1 minute to 24 hours.

<Post-treatment process>
The polymer of this embodiment can be produced through the reaction steps described above. If desired, a post-treatment step may be performed to isolate the polymer produced.
As the post-treatment step, a suitable method can be adopted from known methods. For example, the reaction mixture after the reaction step can be washed with a reaction solvent or water, concentrated, and purified by separation and purification.
As the separation and purification, for example, methods used for separation and purification of ordinary organic compounds, such as distillation, thin film evaporation, degassing under reduced pressure, and reprecipitation, can be employed. The solvent used for the reprecipitation is not particularly limited as long as it is a solvent in which the polymer is insoluble. For example, organic solvents, water, and mixed solvents thereof can be used. Examples of organic solvents include aliphatic hydrocarbons such as pentane, hexane, heptane, and octane, and alcohols such as methanol, ethanol, and propanol. Among them, hexane and methanol are preferred, and hexane is preferred when partial dissolution of a low-molecular-weight polymer is suppressed.

<β-methyl-δ-valerolactone polymer>
The β-methyl-δ-valerolactone-based polymer produced by the production method of the present embodiment described above can be represented by the following general formula (I) as one of preferred embodiments.

In general formula (I), R ¹ is preferably a hydrogen atom, a linear or branched alkyl group having 1 to 20 carbon atoms, a linear or branched alkenyl group having 2 to 20 carbon atoms, or It represents an aryl group of 6 to 12 or an arylalkyl group of 7 to 12 carbon atoms. The "branched alkyl group" has 3 to 20 carbon atoms, and the "branched alkenyl group" has 3 to 20 carbon atoms.
The linear or branched alkyl group having 1 to 20 carbon atoms is preferably a linear or branched alkyl group having 1 to 16 carbon atoms, more preferably 1 to 10 carbon atoms, from the viewpoint of handleability. It is a linear or branched alkyl group, more preferably a linear or branched alkyl group having 1 to 5 carbon atoms. Specifically, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, 1-methylbutyl group, 3-methylbutyl group, n-pentyl group and 2,2-dimethylpropyl group are preferred.

The linear or branched alkenyl group having 2 to 20 carbon atoms is preferably a linear or branched alkenyl group having 2 to 15 carbon atoms, more preferably a linear or branched alkenyl group having 3 to 10 carbon atoms, from the viewpoint of handleability. It is a linear or branched alkenyl group, more preferably a linear or branched alkenyl group having 3 to 6 carbon atoms.

The aryl group having 6 to 12 carbon atoms includes a phenyl group, 2-methylphenyl group, 4-methylphenyl group, 2,4-dimethylphenyl group, 2-naphthyl group and the like. A phenyl group is preferred.
Examples of arylalkyl groups having 7 to 12 carbon atoms include phenylmethyl, phenylethyl, phenylpropyl, phenylbutyl, phenylpentyl, phenylhexyl, naphthylmethyl and naphthylethyl groups. A phenylmethyl group is preferred.

In addition to the above substituents, R ¹ is, as a preferred embodiment, a linear alkyl group having 1 to 20 carbon atoms in which one hydrogen atom bonded to the terminal carbon atom is represented by the following formula (X). One hydrogen atom bonded to at least one terminal carbon atom of a substituted oxygen atom-containing hydrocarbon group or a branched alkyl group having 3 to 20 carbon atoms is substituted with a group represented by the following formula (X) represents an oxygen atom-containing hydrocarbon group. In formula (X), the bond indicated by * bonds to a straight-chain alkyl group having 1 to 20 carbon atoms or a branched alkyl group having 3 to 20 carbon atoms.

R ² in the above formula (X) has the same meaning as R ² described later.
The linear alkyl group having 1 to 20 carbon atoms that bonds to the above formula (X) is preferably a linear alkyl group having 1 to 15 carbon atoms, more preferably a linear alkyl group having 1 to 10 carbon atoms. group, more preferably a straight-chain alkyl group having 2 to 10 carbon atoms, and even more preferably a straight-chain alkyl group having 2 to 5 carbon atoms.
The branched alkyl group having 3 to 20 carbon atoms that bonds to the above formula (X) is preferably a branched alkyl group having 3 to 15 carbon atoms, more preferably a branched alkyl group having 3 to 10 carbon atoms. , more preferably a branched alkyl group having 3 to 6 carbon atoms, and may be a branched alkyl group having 3 to 5 carbon atoms.
Further, one hydrogen atom bonded to all terminal carbon atoms of the branched alkyl group having 3 to 20 carbon atoms is an oxygen atom-containing hydrocarbon group substituted with the group represented by the above formula (X). may

m represents the average repeating number, preferably an integer of 8 to 1,000, more preferably 8 to 800, still more preferably 10 to 500, still more preferably 10 to 300. When m is an integer of 8 or more, the polymer can have a relatively high molecular weight, and the effects of the present invention can be favorably exhibited. Moreover, when m is an integer of 1,000 or less, the polymer is excellent in handleability and productivity.
In R ¹ , when there are a plurality of groups represented by the above formula (X), these may be the same or different.
In formula (I) above, a plurality of R ² and m may be present. When two or more R ² are present, they may be the same or different from each other. Moreover, when there are a plurality of m, these may be the same or different from each other.

R ¹ represents an oxygen atom-containing hydrocarbon group in which one hydrogen atom bonded to a terminal carbon atom in a linear alkyl group having 1 to 20 carbon atoms is substituted with a group represented by the above formula (X); In this case, the following structures can be specifically exemplified as the general formula (I).
<Example 1>
When R ¹ represents an oxygen atom-containing hydrocarbon group in which one hydrogen atom bonded to a terminal carbon atom in a linear alkyl group having Q carbon atoms is replaced with a group represented by the above formula (X), The above general formula (I) is represented by the following general formula (Ia). However, Q is an integer of 1-20.

<Example 2>
When R ¹ represents an oxygen atom-containing hydrocarbon group in which one hydrogen atom bonded to the terminal carbon atom in the ethyl group is replaced with a group represented by the above formula (X), the above general formula (I) is It is represented by the following general formula (Ib).

R ¹ is an oxygen atom-containing hydrocarbon group in which one hydrogen atom bonded to at least one terminal carbon atom of a branched alkyl group having 3 to 20 carbon atoms is substituted with a group represented by the above formula (X). When showing, the following structures can be specifically exemplified as the general formula (I).
<Example 3>
R ¹ is an oxygen atom-containing hydrocarbon group in which one hydrogen atom bonded to the above carbon atoms at all terminal carbon atoms of the 2-methylpropyl group is replaced with a group represented by the above formula (X); When shown, the above general formula (I) is represented by the following general formula (Ic).

<Example 4>
R ¹ is an oxygen atom-containing hydrocarbon in which one hydrogen atom bonded to the above carbon atoms at two terminal carbon atoms of a 2,2-dimethylpropyl group is substituted with a group represented by the above formula (X) When representing a group, the above general formula (I) is represented by the following general formula (Id).

<Example 5>
R ¹ is an oxygen atom-containing hydrocarbon in which one hydrogen atom bonded to the carbon atoms at the two terminal carbon atoms of the 2,2-dimethylbutyl group is replaced with a group represented by the above formula (X). When representing a group, the above general formula (I) is represented by the following general formula (Ie).

<Example 6>
R ¹ is an oxygen atom-containing hydrocarbon in which one hydrogen atom bonded to the above carbon atoms at all terminal carbon atoms of a 2,2-dimethylpropyl group is substituted with a group represented by the above formula (X) When representing a group, the above general formula (I) is represented by the following general formula (If).

R ¹ is, from the viewpoint of reaction efficiency, a linear or branched alkyl group having 1 to 20 carbon atoms, a linear alkenyl group having 2 to 20 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aryl group having 6 to 12 carbon atoms. 12 arylalkyl groups, oxygen atom-containing hydrocarbon groups in which one hydrogen atom bonded to a terminal carbon atom in a straight-chain alkyl group having 1 to 20 carbon atoms is substituted with a group represented by the above formula (X) , or an oxygen atom-containing hydrocarbon group in which one hydrogen atom bonded to at least one terminal carbon atom of a branched alkyl group having 3 to 20 carbon atoms is substituted with a group represented by the above formula (X) Preferably.

In general formula (I), R ² is a linear or branched alkyl group having 1 to 20 carbon atoms, a linear or branched alkenyl group having 2 to 20 carbon atoms, an aryl group having 6 to 12 carbon atoms, Alternatively, it represents an arylalkyl group having 7 to 12 carbon atoms. The "branched alkyl group" has 3 to 20 carbon atoms, and the "branched alkenyl group" has 3 to 20 carbon atoms.
The linear or branched alkyl group having 1 to 20 carbon atoms represented by R ² is preferably a linear or branched alkyl group having 1 to 15 carbon atoms, more preferably carbon A linear or branched alkyl group having 1 to 10 carbon atoms, more preferably a linear or branched alkyl group having 1 to 5 carbon atoms. Specifically, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, 1-methylbutyl group, n-pentyl group and 2,2-dimethylpropyl group are preferred.
The linear or branched alkenyl group having 2 to 20 carbon atoms represented by R ² is preferably a linear or branched alkenyl group having 2 to 15 carbon atoms, more preferably 3, from the viewpoint of handleability. It is a linear or branched alkenyl group having up to 10 carbon atoms, more preferably a linear or branched alkenyl group having 3 to 6 carbon atoms.
The aryl group having 6 to 12 carbon atoms represented by R ² is preferably a phenyl group.
The arylalkyl group having 7 to 12 carbon atoms represented by R ² is preferably a phenylmethyl group.

n represents the average repetition number, preferably an integer of 8 to 1,000, more preferably 8 to 800, still more preferably 10 to 500, still more preferably 10 to 300. When n is an integer of 8 or more, the polymer can have a relatively high molecular weight, and the effects of the present invention can be favorably exhibited. Moreover, when n is an integer of 1,000 or less, the polymer is excellent in handleability and productivity.

(Number average molecular weight)
The number average molecular weight of the polymer is not particularly limited as long as it does not impair the effects of the present invention. The number average molecular weight of the polymer can be, for example, 1,000 or more and 100,000 or less. On the other hand, the number average molecular weight of the polymer is preferably 2,000 or more, preferably 2,500 or more, from the viewpoint that the polymer can have a relatively high molecular weight and can suitably exhibit the effects of the present invention. It may be 3,000 or more. Moreover, from the viewpoint of productivity, the number average molecular weight of the polymer is preferably 80,000 or less, more preferably 50,000 or less. That is, the number average molecular weight of the polymer is preferably 2,000 or more and 80,000 or less.
All "number average molecular weights" described herein are standard polystyrene-equivalent number average molecular weights determined by gel permeation chromatography (GPC) measurement. A detailed measurement method can follow the method described in Examples.

The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited to these.

<Measurement and evaluation method>
Various physical properties were measured or evaluated by the following methods.

[Number average molecular weight]
The ring-opening polymer before terminal modification reaction (before blocking) and the polymer after terminal modification reaction (after blocking) obtained in Examples and Comparative Examples were used as samples, respectively, and were analyzed by gel permeation chromatography (GPC). A number average molecular weight (Mn) was obtained as a standard polystyrene equivalent molecular weight. A specific measuring method is as follows.

<When Mn is less than 15,000>
Samples with Mn less than 15,000 were measured according to the following.
A tetrahydrofuran (THF) solution was used as the eluent. 10 mg of the sample was weighed in terms of resin and dissolved in 1 mL of the above eluent. The solution was passed through a 0.2 μm membrane filter to prepare a measurement sample. The measurement conditions were as follows.
(Measurement condition)
Apparatus: HLC-EcoSEC8320GPC (manufactured by Tosoh Corporation)
Column: KF-803 KF-802.5 Three KF-802 (manufactured by Showa Denko KK) were connected in series.
Eluent: Tetrahydrofuran Flow rate: 0.9 mL/min Sample injection volume: 30 μL
Column temperature: 40°C
Standard polystyrene: PSt Oligomer Kit manufactured by Tosoh Corporation (molecular weight 589-98,900) was used and approximated by a cubic equation.
Detector: RI detector

<When Mn is 15,000 or more>
Samples with Mn greater than 15,000 were measured according to the following.
A tetrahydrofuran (THF) solution was used as the eluent. 1.0 mg of the sample in terms of resin was weighed and dissolved in 1 mL of the above eluent. The solution was passed through a 0.2 μm membrane filter to prepare a measurement sample. The measurement conditions were as follows.
(Measurement condition)
Apparatus: HLC-8220GPC (manufactured by Tosoh Corporation)
Column: Two TSK-gel Super Multipore HZ-M (manufactured by Tosoh Corporation) were connected in series.
Eluent: Tetrahydrofuran Flow rate: 0.35 mL/min Sample injection volume: 10 μL
Column temperature: 40°C
Standard polystyrene: Polystyrene molecular weight standards (molecular weight 580 to 1,214,000) manufactured by GL Sciences Co., Ltd. were used and approximated by a cubic equation.
Detector: RI detector

[Conversion rate of terminal hydroxyl group]
The hydroxyl group conversion rate of poly β-methyl-δ-valerolactone before and after the terminal modification reaction is the same as the ring-opened polymer (before hydroxyl group capping) described in Examples and Comparative Examples and the polymer after the terminal modification reaction (hydroxyl group capping). After) were used as samples, respectively, and determined by ¹ H-NMR. A specific measuring method is as follows.
Device: ECX-400 (manufactured by JEOL Ltd.)
Solvent: deuterated chloroform Calculation method: Adjacent to the terminal hydroxyl group of poly β-methyl-δ-valerolactone relative to the main chain chain [-CH ₂ -O(C=O)] strength of poly β-methyl-δ-valerolactone A methylene peak ( _--CH.sub.2 --OH) intensity ratio was calculated, and a conversion rate was calculated from the intensity ratio before and after the reaction.

[Example 1]
(1) Reaction step A glass four-necked flask with an internal volume of 500 mL was purged with nitrogen, and 7.9 g (90 mmol) of isoamyl alcohol and 231 g (2,025 mmol) of β-methyl-δ-valerolactone were added to obtain 60 °C. 0.84 mL of n-butyllithium (1.6 M hexane solution) was added thereto, and the mixture was stirred at 60° C. for 60 minutes.
Then, 11.0 g (108 mmol) of acetic anhydride and 0.55 g (4.5 mmol) of 4-dimethylaminopyridine dissolved in 5.5 g of β-methyl-δ-valerolactone were placed in the above glass four-necked flask. and stirred at 60° C. for 60 minutes to obtain a reaction solution containing a polymer.
(2) Post-treatment step The obtained reaction solution containing the polymer is extracted with toluene and water, and purified by a thin film evaporator (device name: molecular distillation apparatus MS-300, manufactured by Shibata Scientific Co., Ltd.), 155 g (0.04 mmol) of polymer were obtained.
Table 1 shows the reaction conditions of the above reaction steps, the hydroxyl group conversion rate of poly-β-methyl-δ-valerolactone, and the number average molecular weight.
Further, the obtained polymer is represented by the general formula (I) described above, and R ¹ , R ² and n are as shown in Table 2.

[Examples 2 to 12]
A polymer was obtained in the same manner as in Example 1, except that the conditions were changed to those shown in Table 1.

[Examples 13 to 16]
In Example 1, the procedure was the same as in Example 1, except that the conditions were changed to those shown in Table 1, and the post-treatment steps were extraction with toluene and water, reprecipitation in a large amount of hexane, and purification under reduced pressure at 80°C under vacuum. to obtain a polymer.

[Examples 17-18]
A polymer was obtained in the same manner as in Example 1, except that the conditions were changed to those shown in Table 1.

[Examples 19 to 30]
A polymer was obtained in the same manner as in Example 1, except that the conditions were changed to those shown in Table 1.

[Comparative Example 1]
A four-necked glass flask with an internal volume of 500 mL was purged with nitrogen, 5.6 g (90 mmol) of ethylene glycol and 231 g (2025 mmol) of β-methyl-δ-valerolactone were added, and the temperature was raised to 60°C. 0.78 mL of n-butyllithium (1.6 M hexane solution) was added thereto, and the mixture was stirred at 60° C. for 60 minutes to carry out ring-opening polymerization reaction.
The resulting reaction solution containing the ring-opened polymer was purified by extraction with toluene and water, reprecipitation in a large amount of hexane, and drying under reduced pressure at 80°C.
The above purified ring-opening polymer was placed in a glass four-necked flask having an internal volume of 500 mL, 22.1 g (216 mmol) of acetic anhydride was added, and the mixture was stirred at 100°C for 6 hours to obtain a reaction solution containing the polymer. .
The resulting reaction solution containing the polymer was purified by extraction with toluene and water and distillation to obtain 114 g (0.06 mmol) of the polymer.

[Comparative Example 2]
A polymer was obtained in the same manner as in Comparative Example 1, except that the conditions in Comparative Example 1 were changed to those shown in Table 1.

[Comparative Example 3]
A four-necked glass flask with an internal volume of 500 mL was purged with nitrogen, 5.6 g (90 mmol) of ethylene glycol and 231 g (2,025 mmol) of β-methyl-δ-valerolactone were charged, and the temperature was raised to 60°C. . 0.84 mL of n-butyl lithium (1.6 M hexane solution) was added thereto, and the mixture was stirred at 60° C. for 60 minutes to carry out ring-opening polymerization reaction.
The resulting reaction solution containing the polymer was extracted with toluene and water and purified by a thin film evaporator to obtain 135 g (0.04 mmol) of the polymer.
The obtained polymer is represented by the following structural formula (II), where n and m are as shown in Table 2.

[Comparative Examples 4 to 6]
A polymer was obtained in the same manner as in Comparative Example 1, except that the conditions in Comparative Example 1 were changed to those shown in Table 1.

The polymers obtained in Examples 1 to 18, 24, 29 and 30 and Comparative Examples 4 and 5 are represented by the above general formula (I), and R ¹ , R ² and n are as shown in Table 2. be.
The polymers obtained in Examples 19 to 21, 25, 26 and Comparative Examples 1 and 2 are represented by the above general formula (Ib), and R ¹ , R ² , n and m are shown in Table 2. That's right.
The polymers obtained in Examples 22 and 23 are represented by the above general formula (Ia), and R ¹ , R ² , n and m are as shown in Table 2.
The polymers obtained in Examples 27 and 28 and Comparative Example 6 are represented by the above general formula (Ie), and R ¹ , R ² , n and m are as shown in Table 2.

The notations in Table 2 are as follows.
- In the column of R ¹ , "X" represents the above formula (X).
・In the column of R ² , “n-Pr” indicates an n-propyl group.
- In the ^R2 column, "Ph" indicates a phenyl group.

In the examples, it was possible to produce a terminal-modified β-methyl-δ-valerolactone polymer with a relatively high molecular weight without causing a decrease in molecular weight. In addition, it was easy to carry out the production in one pot, and the reaction was able to proceed under relatively mild temperature conditions.

The production method of this embodiment is particularly suitable for producing a terminal-modified β-methyl-δ-valerolactone polymer with a relatively high molecular weight.

Claims

β-methyl-δ-valero, comprising a step of adding a terminal modifier to a reaction solution obtained by reacting β-methyl-δ-valerolactone, an alcohol compound or water, and a basic catalyst to carry out a terminal modification reaction. A method for producing a lactone polymer.
The production method according to claim 1, wherein after adding the terminal modifier, a terminal modification reaction is performed at a reaction temperature of 20 to 80°C.
The production method according to claim 1 or 2, wherein 1.0 to 20.0 molar equivalents of a terminal modifier are added to the hydroxyl groups of the alcohol compound.
The production method according to any one of claims 1 to 3, wherein the alcohol compound is at least one selected from the group consisting of monoalcohols and polyhydric alcohols.
The production method according to any one of claims 1 to 4, wherein the terminal modifier is at least one selected from the group consisting of acid anhydrides and acid halides.
The terminal modifying agent includes a linear or branched alkyl group having 1 to 20 carbon atoms, a linear or branched alkenyl group having 2 to 20 carbon atoms, an aryl group having 6 to 12 carbon atoms, and 7 to 7 carbon atoms. The production method according to any one of claims 1 to 5, having at least one selected from the group consisting of 12 arylalkyl groups.
The production method according to any one of claims 1 to 6, wherein the β-methyl-δ-valerolactone polymer has a number average molecular weight of 1,000 or more and 100,000 or less.