Polymer production method

Abstract

To provide a production method that can readily produce a polymer with an unsaturated bond in a side chain.SOLUTION: A polymer production method according to one aspect of the present invention includes a transesterification reaction to occur, in the presence of a guanidine organic catalyst, between a copolymer (A) with an acrylate-based unit and an unsaturated bond-containing alcohol (b1), yielding a copolymer (B1) with an unsaturated bond in a side chain. A polymer production method according to another aspect of the present invention includes an amidation reaction to occur, in the presence of a guanidine organic catalyst, between a copolymer (A) with an acrylate-based unit and an unsaturated bond-containing amine (b2), yielding a copolymer (B2) with an unsaturated bond in a side chain.SELECTED DRAWING: None

Description

[Technical Field]

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

[0002] Polymers having unsaturated bonds in their side chains are useful as functional materials. For example, in Patent Document 1, a polymer having carbon-carbon double bonds in its side chains is used as an active energy ray-curable resin. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2005 / 087831 Summary of the Invention [Problem to be solved by the invention]

[0004] To add value to polymers, it is necessary to introduce unsaturated bonds into the side chains of polymers. However, because monomers with unsaturated bonds in the side chains undergo crosslinking and polymerization inhibition reactions, it is difficult to selectively obtain polymers with unsaturated bonds in the side chains by polymerization of monomers. In Patent Document 1, an epoxy group-containing copolymer is obtained, and then the epoxy groups of the copolymer are reacted with a short-chain unsaturated carboxylic acid and a long-chain unsaturated carboxylic acid to introduce unsaturated bonds into the side chains of the polymer, which makes the synthesis process complicated. The present invention provides a method for easily producing a polymer having an unsaturated bond in the side chain. [Means for solving the problem]

[0005] The present invention has the following aspects. [1] A method for producing a polymer, comprising: carrying out a transesterification reaction between a copolymer (A) having acrylate-based units and an unsaturated bond-containing alcohol (b1) in the presence of a guanidine organic catalyst to obtain a copolymer (B1) having an unsaturated bond in its side chain. [2] A method for producing a polymer, comprising: carrying out an amidation reaction between a copolymer (A) having an acrylate-based unit and an amine (b2) containing an unsaturated bond in the presence of a guanidine organic catalyst, to obtain a copolymer (B2) having an unsaturated bond in its side chain. [3] The production method according to [1] or [2], wherein the proportion of the units based on the acrylate is 10 to 80 mass % based on the total structural units of the copolymer (A). [4] The production method according to any one of [1] to [3], wherein the number average molecular weight of the copolymer (A) is 30,000 or more. [5] The production method according to any one of [1] to [4], wherein the glass transition point of the copolymer (A) is 10°C or higher. [6] The method according to any one of [1] to [5], wherein the copolymer (A) is at least one selected from the group consisting of a copolymer having units based on methyl acrylate and units based on methyl methacrylate, a copolymer having units based on n-butyl acrylate and units based on methyl methacrylate, and a copolymer having units based on methyl acrylate and units based on ethylene. [Effects of the Invention]

[0006] According to the present invention, a production method is provided that can easily produce a polymer having an unsaturated bond in the side chain. DETAILED DESCRIPTION OF THE INVENTION

[0007] In this specification, the compound represented by formula (1) will be referred to as compound (1). Compounds represented by other formulas will also be referred to in the same manner. As used herein, the following terms have the following meanings: The number average molecular weight and the glass transition temperature are values ​​determined by the methods described in the examples. The symbol "to" indicating a range of values ​​means that the values ​​before and after it are included as the lower and upper limits.

[0008] <First aspect> In the method for producing a polymer according to the first aspect of the present invention, a copolymer (A) having an acrylate-based unit and an unsaturated bond-containing alcohol (b1) are subjected to a transesterification reaction in the presence of a guanidine organic catalyst to obtain a copolymer (B1) having an unsaturated bond in a side chain.

[0009] (Copolymer (A)) The copolymer (A) has units based on an acrylate (hereinafter referred to as "acrylate units (a1)"). The copolymer (A) may be a copolymer having two or more types of acrylate units (a1); or may be a copolymer having acrylate units (a1) and units based on a monomer other than an acrylate (hereinafter referred to as "other monomer units (a2)"). One type of copolymer (A) may be used alone, or two or more types may be used in combination.

[0010] The acrylate is an acrylic acid ester that does not contain a hydroxy group, an amino group, or an epoxy group. Examples of the acrylate include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, isoamyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, octyl acrylate, lauryl acrylate, stearyl acrylate, isostearyl acrylate, hexadecyl acrylate, nonyl acrylate, isononyl acrylate, phenyl acrylate, benzyl acrylate, cyclohexyl acrylate, tetrahydrofurfuryl acrylate, isobornyl acrylate, 3,5,5-trimethylcyclohexyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, terpene acrylate and its derivatives, hydrogenated rosin acrylate and its derivatives, docosyl acrylate, phenyl acrylate, and 2-methoxyethyl acrylate. However, the acrylate is not limited to these examples. The acrylate may be used alone or in combination of two or more kinds.

[0011] The other monomer is not particularly limited as long as it is copolymerizable with acrylate. Examples include ethylene, propylene, methacrylate, styrene and its derivatives, and acrylonitrile. However, the other monomer is not limited to these examples. The other monomers may be used alone or in combination of two or more.

[0012] The copolymer (A) is preferably at least one selected from the group consisting of the following copolymers (A1), (A2) and (A3). Copolymer (A1): a copolymer having units based on methyl acrylate and units based on methyl methacrylate; Copolymer (A2): A copolymer having units based on n-butyl acrylate and units based on methyl methacrylate Copolymer (A3): A copolymer having units based on methyl acrylate and units based on ethylene.

[0013] The copolymer (A) may be a copolymer having two or more types of acrylate units (a1). When the copolymer (A) has other monomer units (a2), the proportion of the acrylate units (a1) is preferably 5 to 99 mass% and more preferably 10 to 80 mass% of the total structural units of the copolymer (A). When the proportion of the acrylate units (a1) is equal to or greater than the lower limit of the above-mentioned range, a copolymer having a larger number of unsaturated bonds in its side chains is likely to be obtained. When the proportion of the acrylate units (a1) is equal to or less than the upper limit of the above-mentioned range, the yield of the copolymer having unsaturated bonds in its side chains is likely to be improved.

[0014] When the copolymer (A) contains the other monomer unit (a2), the proportion of the other monomer unit (a2) is preferably 1 to 95 mass% and more preferably 20 to 90 mass% of the total structural units of the copolymer (A). When the proportion of the other monomer unit (a2) is equal to or greater than the lower limit of the above-mentioned range, the yield of the copolymer having an unsaturated bond in the side chain is likely to be improved. When the proportion of the other monomer unit (a2) is equal to or less than the upper limit of the above-mentioned range, the copolymer having a larger number of unsaturated bonds in the side chain is likely to be obtained.

[0015] The number average molecular weight of the copolymer (A) is preferably 30,000 or more, more preferably 30,000 to 500,000, and even more preferably 30,000 to 200,000. When the number average molecular weight of the copolymer (A) is 30,000 or more, the copolymer obtained after the reaction is easily applicable to applications such as molding materials, pressure-sensitive adhesives, etc. When the number average molecular weight of the copolymer (A) is equal to or less than the upper limit of the above numerical range, the copolymer obtained after the reaction is easily applicable to applications such as paints, etc.

[0016] The glass transition point of the copolymer (A) is preferably 10°C or higher, more preferably 10 to 150°C, and even more preferably 10 to 120°C. When there are multiple glass transition points, the highest glass transition point is taken as the glass transition point of the copolymer (A). When the glass transition point of the copolymer (A) is 10°C or higher, the copolymer obtained after the reaction is easily applicable to applications such as molding materials. When the glass transition point of the copolymer (A) is equal to or lower than the upper limit of the above numerical range, the copolymer obtained after the reaction is easily applicable to applications such as paints, pressure-sensitive adhesives, etc.

[0017] (Unsaturated bond-containing alcohol (b1)) The unsaturated bond-containing alcohol (b1) is an alcohol having a monovalent hydrocarbon group with an unsaturated bond. The number of unsaturated bonds is not particularly limited, and may be one or more. Examples of the unsaturated bond-containing alcohol (b1) include allyl alcohol, 3-buten-1-ol, 4-penten-1-ol, 1,3-butadien-1-ol, furfuryl alcohol, geraniol, linalool, nerol, and citronellol, although the unsaturated bond-containing alcohol (b1) is not limited to these examples. The unsaturated bond-containing alcohol (b1) may be used alone or in combination of two or more kinds.

[0018] (Guanidine Organocatalyst) The guanidine organic catalyst functions as a catalyst in the transesterification reaction between the copolymer (A) and the unsaturated bond-containing alcohol (b1). In the present invention, the use of the guanidine organic catalyst improves the conversion rate of the transesterification reaction.

[0019] Examples of the guanidine organic catalyst include the following compounds (1), (2), (3), and (4).

[0020] [ka]

[0021] Among them, the compound (1), ie, 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), is preferred as the guanidine organic catalyst.

[0022] (Transesterification reaction) In the first embodiment, a transesterification reaction occurs between the acrylate unit (a1) and the unsaturated bond-containing alcohol (b1). The acrylate unit (a1) is converted to -(CHCH(C(=O)OR a1 ))-, and the unsaturated bond-containing alcohol (b1) is represented by R b1 When expressed as -OH, R a1 and R b1 A transesterification reaction occurs between (R b1is a monovalent organic group having an unsaturated bond. As a result, at least some of the R a1 R b1 As a result, a copolymer (B1) is obtained in which the unsaturated bond-containing group is bonded to the side chain via an ester bond. The copolymer (B1) may be obtained by transesterifying all of the acrylate units (a1) of the copolymer (A1), or by transesterifying only a portion of the acrylate units (a1).

[0023] The reaction temperature of the transesterification reaction is not particularly limited, but is preferably, for example, 70 to 200°C. When the reaction temperature of the transesterification reaction is equal to or higher than the lower limit of the above-mentioned range, the conversion rate of the transesterification reaction is likely to be improved. When the reaction temperature of the transesterification reaction is equal to or lower than the upper limit of the above-mentioned range, decomposition of the catalyst is suppressed.

[0024] The reaction time of the transesterification reaction is not particularly limited, but is preferably, for example, 0.5 to 24 hours. When the reaction time of the transesterification reaction is equal to or greater than the lower limit of the above-mentioned range, the conversion rate of the transesterification reaction is likely to be improved. When the reaction time of the transesterification reaction is equal to or less than the upper limit of the above-mentioned range, productivity is likely to be improved.

[0025] The transesterification reaction may be carried out in a solvent or without a solvent. The solvent is not particularly limited as long as it is a compound inert to the transesterification reaction. Alternatively, the unsaturated bond-containing alcohol (b1) may be used as the solvent. Examples of the solvent include aromatic hydrocarbons such as toluene and xylene, and polar solvents such as N,N-dimethylformamide, dimethyl sulfoxide, and acetonitrile. One type of solvent may be used alone, or two or more types may be used in combination.

[0026] When carrying out the transesterification reaction, a molecular sieve may be added to remove alcohols produced by the reaction. The amount of molecular sieve used is preferably 5 to 50 mass % and more preferably 10 to 30 mass % relative to the copolymer (A1). When the amount of molecular sieve used is equal to or greater than the lower limit of the above-mentioned range, the conversion rate of the transesterification reaction is likely to be improved. When the amount of molecular sieve used is equal to or less than the upper limit of the above-mentioned range, the reaction solution is easily stirred.

[0027] (Mechanism of action of the first aspect) In the embodiment described above using one example, a transesterification reaction is carried out between the copolymer (A) and the unsaturated bond-containing alcohol (b1) in the presence of a guanidine organic catalyst, thereby enabling the selective and easy production of a copolymer (B1) having an unsaturated bond in its side chain. Furthermore, the production method according to this embodiment does not require the complex synthesis steps described in Patent Document 1. Since the molecular weight of the copolymer (B1) can be controlled by controlling the molecular weight of the unsaturated bond-containing alcohol (b1), the molecular weight after the introduction of the unsaturated bond can be increased or decreased, making it easier to control the length of the side chain, compared to Patent Document 1. Furthermore, since OH groups are less likely to remain after the introduction of the unsaturated bond, surface free energy can be easily controlled. Furthermore, the wide variety of unsaturated bond-containing alcohols (b1) available allows for the introduction of a variety of unsaturated bonds, providing the advantage of a high degree of freedom in polymer structure.

[0028] <Second aspect> In the method for producing a polymer according to the second aspect of the present invention, an amidation reaction is carried out between a copolymer (A) having an acrylate unit (a1) and an unsaturated bond-containing amine (b2) in the presence of a guanidine organic catalyst to obtain a copolymer (B2) having an unsaturated bond in its side chain. The details and preferred embodiments of the copolymer (A) are the same as those explained in the first embodiment.

[0029] (Unsaturated bond-containing amine (b2)) The unsaturated bond-containing amine (b2) is an amine having a monovalent hydrocarbon group having an unsaturated bond. The number of unsaturated bonds is not particularly limited, and may be one or more. Examples of the unsaturated bond-containing amine (b2) include allylamine, 3-butene-1-amine, 4-pentene-1-amine, and 1,3-butadiene-1-amine, although the unsaturated bond-containing amine (b2) is not limited to these examples. The unsaturated bond-containing amine (b2) may be used alone or in combination of two or more kinds.

[0030] (Guanidine Organocatalyst) In a second embodiment, the guanidine organic catalyst functions as a catalyst in the amidation reaction between the copolymer (A) and the unsaturated bond-containing amine (b2). The details and preferred embodiments of the guanidine organic catalyst are the same as those described in the first embodiment. In the second embodiment, the use of 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) increases the yield of the amidation reaction.

[0031] (Amidation reaction) In the second embodiment, an amidation reaction occurs between the acrylate unit (a1) and the unsaturated bond-containing amine (b2). The acrylate unit (a1) is converted to -(CHCH(C(=O)OR a1 ))-, and the unsaturated bond-containing amine (b2) is represented by N(R b2 )(R b3 )H, R a1 and R b2 , R b3 An amidation reaction occurs between (R b2 , R b3 are each independently a monovalent organic group having an unsaturated bond or a hydrogen atom, and are not simultaneously hydrogen atoms. As a result, at least some of the R a1 R b2 or R b3 As a result, a copolymer (B2) is obtained in which the unsaturated bond-containing group is bonded to the side chain via an amide bond. The copolymer (B2) may be a copolymer (A1) in which all of the acrylate units (a1) have been amidated, or a copolymer (A1) in which only a portion of the acrylate units (a1) have been amidated.

[0032] The reaction temperature of the amidation reaction is not particularly limited, but is preferably, for example, 70 to 200°C. When the reaction temperature of the amidation reaction is equal to or higher than the lower limit of the above-mentioned range, the yield of the amidation reaction is likely to be improved. When the reaction temperature of the amidation reaction is equal to or lower than the upper limit of the above-mentioned range, decomposition of the catalyst is likely to be suppressed.

[0033] The reaction time of the amidation reaction is not particularly limited, but is preferably, for example, 0.5 to 24 hours. When the reaction time of the amidation reaction is equal to or greater than the lower limit of the above-mentioned range, the conversion rate of the amidation reaction is likely to be improved. When the reaction time of the amidation reaction is equal to or less than the upper limit of the above-mentioned range, productivity is likely to be improved.

[0034] In the second embodiment, the amidation reaction may be carried out in a solvent or without a solvent. The solvent is not particularly limited as long as it is a compound inert to the amidation reaction. Examples of the solvent include the same compounds as those exemplified in the first embodiment.

[0035] (Mechanism of action of the second aspect) In one embodiment described above using one example, an amidation reaction is carried out between the copolymer (A) and the unsaturated bond-containing amine (b2) in the presence of a guanidine organic catalyst, thereby enabling the selective and easy production of a copolymer (B2) having an unsaturated bond in its side chain. Furthermore, the production method according to this embodiment does not require the complex synthesis steps described in Patent Document 1. The molecular weight of the copolymer (B2) can be controlled by controlling the molecular weight of the unsaturated bond-containing amine (b2). Therefore, compared to Patent Document 1, the molecular weight after the introduction of the unsaturated bond can be increased or decreased, and the length of the side chain can be easily controlled. Furthermore, since there are a wide variety of unsaturated bond-containing amines (b2), there is the advantage that various unsaturated bonds can be introduced, resulting in a high degree of freedom in the polymer structure.

[0036] Although one embodiment has been described above by showing one example embodiment, the present invention is not limited to the example embodiment disclosed in this specification and can be appropriately modified and implemented without departing from the spirit of the invention. The embodiment disclosed in this specification can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. [Example]

[0037] The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following description.

[0038] <Abbreviation> The abbreviations used in the examples are as follows.

[0039] (acrylate) MA: Methyl acrylate BA: Butyl acrylate

[0040] (methacrylate) MMA: Methyl methacrylate

[0041] (Other monomers) Et: Ethylene

[0042] (catalyst) TBD: 1,5,7-triazabicyclo[4.4.0]dec-5-ene TEA: Triethylamine

[0043] <Measurement method> (Mn, Mw) The number average molecular weight (Mn) and the mass average molecular weight (Mw) were calculated from a calibration curve of polymethyl methacrylate (PMMA) using gel permeation chromatography (GPC). Specifically, 5 mg of the polymer to be measured was dissolved in 5 ml of tetrahydrofuran, and the solution was filtered through a 0.45 μm filter to prepare a sample for GPC measurement. A high molecular weight measurement guard column (manufactured by Tosoh Corporation, product name "TSK-guardcolumn SUPER H-H 4.6mmφ×35mm") and two high molecular weight measurement columns (manufactured by Tosoh Corporation, product name "TSK-GEL SUPER HM-H 6.0mmφ×150mm") were connected in series and used with a gel permeation chromatography measuring device (manufactured by Tosoh Corporation, product name "HLC-8420GPC"). A differential refractometer (RI) was used as the detector. Measurements were carried out under the conditions of a separation column temperature of 40 °C, a mobile phase of tetrahydrofuran, a flow rate of the mobile phase of 0.6 mL / min, and a sample injection volume of 10 μL. Calibration curves were created using several types of polymethyl methacrylate with known molecular weights (products of Mitsubishi Chemical Corporation) as standard polymers, and Mn and Mw were determined.

[0044] (Glass transition temperature (°C)) The glass transition temperature (°C) was measured using a differential scanning calorimeter (X-DSC7000, manufactured by Hitachi High-Tech Sciences Corporation). The temperature was raised from -30 to 150 °C at a rate of 10 °C / min, and then the temperature was lowered from 150 to -30 °C at a rate of 10 °C / min. This cycle was repeated twice, and the glass transition temperature (°C) was measured from the second heating process.

[0045] (Conversion rate (%)) The conversion rate (%) was calculated from the following formula. Conversion rate (%) = (n1 / n0) × 100 In the formula, n1 is the number of moles (mol) of acrylate units derived from alcohol in the polymer after the transesterification reaction, and n0 is the number of moles (mol) of acrylate units in the polymer before the transesterification reaction. n0 and n1 were determined by analysis using 1 HNMR.

[0046] (Synthesis of MMA-MA copolymer) 90 parts by mass of MMA and 10 parts by mass of MA were added to 100 parts by mass of toluene, and 0.5 parts by mass of azobisisobutyronitrile was added as an initiator. The mixture was stirred at 70°C for 5 hours. The reaction solution was then reprecipitated in hexane to obtain an MMA-MA copolymer. The reading on the thermometer in the heat medium was taken as the reaction temperature. The reaction time was measured from the time the reaction solution was immersed in the heat medium to the time it was removed from the heat medium.

[0047] Example 1 Copolymer (A), toluene as a solvent, unsaturated bond-containing alcohol (b1), and TBD catalyst were added to a reactor to obtain the composition shown in Table 1, and molecular sieves were then added. The mixture was heated to 120°C and stirred for 6 hours. After the reaction was completed, the reaction solution was added dropwise to a reprecipitation solvent (hexane) and stirred to obtain copolymer (B1). The value measured by the thermometer in the heat medium was taken as the reaction temperature, and the reaction time was taken as the time from when the reaction solution was immersed in the heat medium to when it was removed from the heat medium.

[0048] <Examples 2 to 6, Comparative Examples 1 to 3> The experiment was carried out in the same manner as in Example 1, except that the composition of the copolymer (A), the unsaturated bond-containing alcohol (b1), the amount of catalyst used, and the reaction temperature were changed as shown in Table 1.

[0049] The copolymer (A) used in each example is as follows: Examples 1 and 4, Comparative Example 1: MMA-MA copolymer Examples 2 and 5, Comparative Example 2: Kuraray's product "Kurarity" Examples 3 and 6, Comparative Example 3: Mitsubishi Chemical Corporation product "REXPEARL"

[0050] [Table 1]

[0051] In Examples 1 to 6, in which TBD was used as a catalyst, the transesterification reaction proceeded, a high conversion rate was achieved, and a copolymer having unsaturated double bonds was obtained. In contrast, in Comparative Examples 1 to 3, in which TEA was used as a catalyst, the transesterification reaction did not proceed. [Industrial Applicability]

[0052] According to the present invention, a production method is provided that can easily produce a polymer having an unsaturated bond in the side chain.

Claims

1. A method for producing a polymer, comprising: carrying out a transesterification reaction between a copolymer (A) having an acrylate-based unit and an unsaturated bond-containing alcohol (b1) in the presence of a guanidine organic catalyst to obtain a copolymer (B1) having an unsaturated bond in a side chain.

2. A method for producing a polymer, comprising: carrying out an amidation reaction between a copolymer (A) having an acrylate-based unit and an unsaturated bond-containing amine (b2) in the presence of a guanidine organic catalyst to obtain a copolymer (B2) having an unsaturated bond in a side chain.

3. 3. The production method according to claim 1, wherein the proportion of the acrylate-based units is 10 to 80% by mass based on all structural units of the copolymer (A).

4. 3. The method according to claim 1, wherein the number average molecular weight of the copolymer (A) is 30,000 or more.

5. 3. The method according to claim 1, wherein the glass transition temperature of the copolymer (A) is 10°C or higher.

6. 3. The production method according to claim 1 or 2, wherein the copolymer (A) is at least one selected from the group consisting of a copolymer having units based on methyl acrylate and units based on methyl methacrylate, a copolymer having units based on n-butyl acrylate and units based on methyl methacrylate, and a copolymer having units based on methyl acrylate and units based on ethylene.

Images