TWI712619B - Manufacturing method of vinyl ether polymer using onium salt - Google Patents

Abstract

(式中，R ¹表示碳數1~3之烷基，n為1~10之整數) 表示之乙烯基醚單體之至少1種，及/或 下述通式(2)：

(式中，R ²為碳數1~10之脂肪族烴基、脂環式烴基、烯丙基) 表示之乙烯基醚單體之至少1種，使用鎓鹽作為聚合起始劑於無溶劑下聚合之步驟而成。 [Problem] The subject of the present invention is to provide a method for producing a vinyl ether polymer, which is a simple and convenient method for producing a vinyl ether polymer that does not use both metal catalysts and organic solvents and does not require low-temperature reaction . [Solution] A method for producing vinyl ether polymer, which includes the following general formula (1):

(In the formula, R ¹ represents an alkyl group with a carbon number of 1 to 3, and n is an integer of 1 to 10) at least one of the vinyl ether monomers represented, and/or the following general formula (2):

(In the formula, R ² is a C 1-10 aliphatic hydrocarbon group, alicyclic hydrocarbon group, allyl group) represents at least one of the vinyl ether monomers, using onium salt as polymerization initiator in the absence of solvent The steps of polymerization are made.

Description

Manufacturing method of vinyl ether polymer using onium salt

The present invention relates to a method for producing vinyl ether polymers using onium salts.

Vinyl ether polymers are used as blending ingredients for adhesives, coatings, and lubricants. In addition, it has characteristics such as thermal stimulus responsiveness or biocompatibility, and can be used in dispersants, metal recovery resins, anti-thrombotic materials, etc., using its characteristics.

The vinyl ether monomer, which is the raw material of the vinyl ether polymer, is a monomer with cationic polymerizability. Therefore, generally speaking, it is polymerization using Lewis acid.

For example, Patent Document 1 discloses a method for producing a vinyl ether polymer using boron trifluoride diethyl ether complex. In more detail, by using two monomers of n-butyl vinyl ether and tricyclodecane vinyl ether in toluene, using boron trifluoride diethyl ether complex at -30°C Polymerization to synthesize random copolymers.

In addition, Patent Document 2 discloses a method for producing a vinyl ether polymer using aluminum alkyl as Lewis acid. In more detail, by using two monomers of cyclohexyl vinyl ether and methoxyethyl vinyl ether, in toluene, 1,4-dioxane is used as the added base, and Et1.5AlCl1 is used. 5 As Lewis acid, polymerize at 0°C to synthesize block copolymer.

The above-mentioned polymerization is carried out by using a semi-metal catalyst or a metal catalyst in an organic solvent at a low temperature reaction below 0°C. However, when using a semi-metal catalyst or a metal catalyst, the removal step of the catalyst is necessary, so a purification step after polymerization is necessary. In addition, when an organic solvent is used, it is also necessary to distill off the organic solvent in the purification step. Furthermore, low-temperature reactions below 0°C require a large-scale cooling device, so there is a problem that it is difficult to scale up.

As a method for solving the above-mentioned problems, Patent Document 3 discloses a polymerization method using a vinyl ether monomer of heteropoly acid. In more detail, the vinyl ether polymer is synthesized by polymerizing ethyl vinyl ether monomer in cyclohexane in the presence of phosphotungstic acid at room temperature. In the invention described in Patent Document 3, the reaction can be performed at room temperature, but the catalyst used is a metal catalyst and an organic solvent is used, so the three problems have not been solved simultaneously.

On the other hand, a polymerization method that does not use a metal catalyst and can react at a high temperature has been proposed. For example, Non-Patent Document 1 describes a polymerization method using a hydrochloric acid etherate catalyst. In more detail, a vinyl ether polymer is synthesized by polymerizing various vinyl ether monomers in toluene or hexane in the presence of dioxane and hydrochloride etherate catalysts. The invention described in Non-Patent Document 1 does not use a metal catalyst and can react at a high temperature of up to 65°C. However, it is necessary to add dioxane, which is a carcinogenic substance, and an organic solvent is also necessary, so it is also used in this system. Three issues were not solved simultaneously. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] JP 2007-231227 A [Patent Document 2] JP 2016-50266 A [Patent Document 3] JP 2000-143711 A [Non-Patent Literature]

[Non-Patent Document 1] J. Polym. Sci. Part A: Polym. Chem. 46, 1913 (2008)

[The problem to be solved by the invention]

The subject of the present invention is to provide a method for producing vinyl ether polymers, which is a simple and convenient method for producing vinyl ether polymers that does not use both metal catalysts and organic solvents, and does not require low-temperature reactions below 0°C . [Means to solve the problem]

In order to solve the above-mentioned problems, the inventors of the present invention repeated intensive studies and found that by not using a metal catalyst and using a specific polymerization initiator to polymerize vinyl ether monomers without solvent, ethylene can be obtained. Base ether polymer. Furthermore, it was discovered that by adding a cyclic carbonate to the polymerization system, the temperature rise of the polymerization system can be suppressed, and the present invention has been completed.

(式中，R ¹表示碳數1~3之烷基，n為1~10之整數) 表示之乙烯基醚單體之至少1種，及/或 下述通式(2)：

(式中，R ²為碳數1~10之脂肪族烴基、脂環式烴基、芳香族烴基) 表示之乙烯基醚單體之至少1種，使用鎓鹽作為聚合起始劑於無溶劑下聚合之步驟而成。 That is, the present invention provides the following <1> to <7>. <1> A method for producing a vinyl ether polymer, which includes the following general formula (1):

(In the formula, R ¹ represents an alkyl group with a carbon number of 1 to 3, and n is an integer of 1 to 10) at least one of the vinyl ether monomers represented, and/or the following general formula (2):

(In the formula, R ² is a C1-C10 aliphatic hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group) represents at least one of the vinyl ether monomers, using onium salt as a polymerization initiator in the absence of solvent The steps of polymerization are made.

<2> The production method according to <1>, wherein the onium salt is at least one selected from the group consisting of iodonium salt, oxonium salt, sulphur salt, and bromium salt.

<3> The manufacturing method of <1> or <2>, wherein the amount of the onium salt is in the range of 0.1-15% by mass relative to the total amount of the vinyl ether monomer.

<4> The production method according to any one of <1> to <3>, wherein in the aforementioned polymerization step, a cyclic carbonate is further used.

<5> The manufacturing method of <4>, wherein the cyclic carbonate is propylene carbonate.

<6> The manufacturing method of any one of <1> to <5>, wherein the polymerization temperature in the aforementioned polymerization step is 20°C or higher.

<7> The manufacturing method of any one of <1> to <6>, wherein the weight average molecular weight of the aforementioned vinyl ether monomer is in the range of 1,000 to 50,000. [Effects of Invention]

According to the manufacturing method of the vinyl ether polymer of the present invention, the vinyl ether polymer can be obtained by polymerizing the vinyl ether monomer without a solvent without using a metal catalyst and using a specific polymerization initiator. According to such a manufacturing method, the polymerization reaction can be carried out under normal temperature to high temperature conditions instead of low temperature conditions below 0°C. Therefore, no cooling device is required, and the industrial advantage is great.

＜Method of manufacturing vinyl ether polymer＞ The method for producing a vinyl ether polymer of the present invention is characterized by including a step of polymerizing a vinyl ether monomer under specific conditions. Hereinafter, the polymerization step will be described in detail.

(式中，R ¹表示碳數1~3之烷基，n為1~10之整數) 表示之單體。 <Monomer component> The vinyl ether monomer used in the polymerization of the present invention may have the following general formula (1):

(In the formula, R ¹ represents an alkyl group with a carbon number of 1 to 3, and n is an integer of 1 to 10) represents the monomer.

In the general formula (1), the carbon number of the alkyl group represented by R ¹ is 1 to 3, preferably 1 or 2. The alkyl group may be linear or branched, and specific examples include methyl, ethyl, n-propyl, and isopropyl. Among these, as the alkyl group, methyl and ethyl are particularly preferred; and methyl is more preferred.

In the general formula (1), n is an integer from 1 to 10, preferably an integer from 1 to 6, more preferably an integer from 1 to 4, and particularly preferably an integer from 1 to 3.

Examples of monomers represented by the general formula (1) include 2-methoxyethyl vinyl ether, 2-ethoxyethyl vinyl ether, 2-(2-methoxyethoxy)ethyl Vinyl ether, 2-(2-ethoxyethoxy) ethyl vinyl ether, 2-(2-(2-methoxyethoxy) ethoxy) ethyl vinyl ether (triethylene two Alcohol monomethyl vinyl ether), 2-(2-(2-ethoxyethoxy)ethoxy)ethyl vinyl ether, 2-(2-(2-(2-methoxyethoxy) Group) ethoxy) ethoxy) ethyl vinyl ether and the like.

(式中，R ²為碳數1~10之脂肪族烴基、脂環式烴基、芳香族烴基) 表示之單體。 In addition, the vinyl ether monomer used in the polymerization of the present invention may be the following general formula (2):

(In the formula, R ² is a C 1-10 aliphatic hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group) represents a monomer.

In the general formula (2), the carbon number of the aliphatic hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group represented by R ² is 1-10, preferably 1-8. The aliphatic hydrocarbon group may be linear or branched.

Examples of monomers represented by the general formula (2) include methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, sec -Butyl vinyl ether, isobutyl vinyl ether, tert-butyl vinyl ether, n-pentyl vinyl ether, n-hexyl vinyl ether, n-heptyl vinyl ether, n-octyl ethylene Base ether, ethylhexyl vinyl ether, n-nonyl vinyl ether, n-decyl vinyl ether, cyclohexyl vinyl ether, tricyclodecyl vinyl ether, phenyl vinyl ether, etc.

The R ¹ and R ² moieties in the general formulas (1) and (2) may have a substituent, and examples of the substituent include a silyl group, an ester group, and a halogen.

＜Onium salt＞ The onium salt used in the polymerization of the present invention includes, for example, bis(2,4,6-trimethylpyridine)bromonium hexafluorophosphate and the like bromide; (4-methylphenyl)[4-(2 -Methylpropyl) phenyl) iodonium hexafluorophosphate, bis(4-tert-butylphenyl) iodonium hexafluorophosphate, diphenyl iodonium hexafluorophosphate, diphenyl iodonium chloride, diphenyl Iodonium salt, 4-isopropyl-4'-methyldiphenyl iodonium (pentafluorophenyl) borate, (4-nitrophenyl) (phenyl) iodonium trifluoromethanesulfonate, etc. The iodonium salt; 2,6-di-tert-butyl-4-methylpyrylium trifluoromethanesulfonate, 2,4,6-trimethylpyrylium tetrafluoroborate and other oxonium salts ; (2-Bromoethyl) diphenyl sulfonium trifluoromethane sulfonate, (2-carboxyethyl) dimethyl sulfonium chloride, (2-carboxyethyl) dimethyl sulfonium bromide, triphenyl Caenium bromium salt and other sulfonium salts. Among these, from the viewpoint of reactivity, it is particularly selected from (4-methylphenyl)[4-(2-methylpropyl)phenyl]-Igonia hexafluorophosphate, bis(4-tert- Butylphenyl) iodonium hexafluorophosphate, diphenyl iodonium hexafluorophosphate, diphenyl iodonium salt, 4-isopropyl-4'-methyl diphenyl iodonium (pentafluorophenyl) boric acid Salt, 2,6-di-tert-butyl-4-methylpyrylium trifluoromethanesulfonate, (2-bromoethyl)diphenyl sulfonate trifluoromethanesulfonate, bis(2,4 At least one of the group of ,6-trimethylpyridine)-bromonium hexafluorophosphate is preferred.

The amount of onium salt used is preferably 0.1 to 15% by mass, more preferably 0.1 to 10% by mass, and particularly preferably 0.1 to 5% by mass relative to the total amount of monomer components. If the amount of the onium salt used is within the above range, the polymerization reaction can be carried out at an appropriate polymerization rate.

＜Cyclic Carbonate＞ In the polymerization reaction of the present invention, cyclic carbonate may be further used. By using cyclic carbonate, the temperature rise in the polymerization system can be suppressed, and the range of the internal temperature rise in the polymerization system and the polymerization speed can be adjusted. Examples of the cyclic carbonate include ethylene carbonate, propylene carbonate, and butyl carbonate. Among these, from the viewpoint of suppressing temperature rise, propylene carbonate is particularly preferred. The increase in internal temperature in the present invention is a value measured from the increase in internal temperature during one of the polymerizations based on the internal temperature before the start of polymerization using a thermocouple.

The amount of cyclic carbonate used is preferably 0.1 to 20% by mass, more preferably 0.1 to 10% by mass, and particularly preferably 0.1 to 5% by mass relative to the total amount of monomer components.

＜Vinyl ether polymer＞ In the present invention, the weight average molecular weight (Mw) of the vinyl ether polymer can be appropriately set according to its use and is not particularly limited. For example, from the viewpoint of exhibiting high molecular weight, the weight average molecular weight (Mw) is preferably in the range of 1,000 to 50,000, more preferably in the range of 1,000 to 30,000. In addition, from the viewpoint of homogenizing the properties of the polymer, the molecular weight distribution (Mw/Mn) is preferably 1.2 to 4.0, more preferably 1.3 to 3.9, and particularly preferably 1.5 to 2.0.

<polymerization step> The polymerization temperature in the polymerization reaction of the present invention varies depending on the type of onium salt used, the monomer components, the presence of organic solvents, and the presence of cyclic carbonates, but it can be from room temperature to high temperature instead of below 0°C The low temperature is generally above 20°C, preferably above 30°C; preferably below 100°C, more preferably below 90°C, still more preferably below 80°C, particularly preferably below 70°C.

Although the polymerization time in the polymerization reaction of the present invention varies depending on the system, it is usually 1 hour to 36 hours, preferably 1 hour to 24 hours, and more preferably 1 hour to 18 hours.

The internal temperature rise in the polymerization system of the present invention is usually adjusted to 0.1°C to 120°C, preferably 0.1°C to 100°C, more preferably 0.1°C to 80°C, particularly preferably 0.5°C to 80°C .

The polymerization reaction of the present invention can also be performed by shielding light. By shielding light to carry out the polymerization reaction, the runaway reaction of the vinyl ether monomer caused by the photocracking of the onium salt can be suppressed.

The polymerization reaction of the present invention can be suitably carried out by any method of batch type or continuous type. After the polymerization reaction, if necessary, in order to remove unreacted monomers, purification treatment may be performed by a known method. [Example]

The following examples are used to illustrate the present invention in more detail, but the present invention is not limited in any way by these examples. Furthermore, in the examples, the number average molecular weight (Mn), weight average molecular weight (Mw) and molecular weight distribution (Mw/Mn) of the polymer are obtained from the molecular weight analysis results of gel permeation chromatography (GPC) (polystyrene Ethylene conversion). The analysis equipment and measurement conditions are as follows. ＜Device/Conditions＞ ･Device: "HLC-8320GPC" manufactured by Tosoh Corporation ･Detector: RI detector ･Mobile phase: Tetrahydrofuran ･Flow rate: 1mL/min ･Pipe column: "Shodex LF-804" manufactured by Showa Denko Co., Ltd. x 3 ･Column temperature: 40℃

[Example 1] 30 g of 2-methoxyethyl vinyl ether (hereinafter, MOVE) and 0.45 g of bis(4-tert-butylphenyl) hexafluorophosphate were put into a 300 mL flask. The inside of the reaction vessel was shielded from light by covering the flask with aluminum foil. Next, the inside of the reaction system was heated to 50°C. Next, stirring was performed, and the polymerization reaction was performed for 15 hours while adjusting the polymerization temperature to maintain the polymerization temperature. After the completion of the polymerization reaction, as a result of analyzing the properties of the polymer, the Mw of the polymer produced was 16126 and the Mw/Mn was 2.64.

[Example 2] Put 30 g of MOVE and 0.45 g of diphenyl hexafluorophosphate into a 300 mL flask. The inside of the reaction vessel was shielded from light by covering the flask with aluminum foil. Next, the inside of the reaction system was heated to 50°C. Next, stirring was performed, while adjusting the polymerization temperature so as to maintain the polymerization temperature, the polymerization reaction was performed for 7 hours. After the completion of the polymerization reaction, the result of analyzing the properties of the polymer showed that the Mw of the polymer produced was 25928 and the Mw/Mn was 1.97.

[Example 3] Put 30 g of MOVE and 0.45 g of diphenyl iodonium salt into a 300 mL flask. The inside of the reaction vessel was shielded from light by covering the flask with aluminum foil. Next, the inside of the reaction system was heated to 70°C. Next, stirring was performed, and the polymerization reaction was performed for 16.5 hours while adjusting the polymerization temperature to maintain the polymerization temperature. After the completion of the polymerization reaction, the result of analyzing the properties of the polymer showed that the Mw of the polymer produced was 1259 and the Mw/Mn was 1.30.

[Example 4] Put 30 g of MOVE, and 0.45 g of 4-isopropyl-4'-methyldiphenyl bis (pentafluorophenyl) borate into a 300 mL flask. The inside of the reaction vessel was shielded from light by covering the flask with aluminum foil. Next, the inside of the reaction system was heated to 70°C. Next, stirring was performed, and the polymerization reaction was performed for 1 hour while adjusting the polymerization temperature to maintain the polymerization temperature. After the polymerization reaction was completed, the properties of the polymer were analyzed, and the Mw of the polymer produced was 7721 and Mw/Mn was 2.48.

[Example 5] Put 30 g of MOVE, and 0.45 g of 2,6-di-tert-butyl-4-methylpyrylium trifluoromethanesulfonate into a 300 mL flask. The inside of the reaction vessel was shielded from light by covering the flask with aluminum foil. Next, the inside of the reaction system was heated to 30°C. Next, stirring was performed, and the polymerization reaction was performed for 1 hour while adjusting the polymerization temperature to maintain the polymerization temperature. After the polymerization reaction was completed, as a result of analyzing the properties of the polymer, the Mw of the polymer produced was 8203 and the Mw/Mn was 3.89.

[Example 6] Put 30 g of MOVE and 0.45 g of (2-bromoethyl) diphenyl sulfonate trifluoromethanesulfonate into a 300 mL flask. The inside of the reaction vessel was shielded from light by covering the flask with aluminum foil. Next, the inside of the reaction system was heated to 50°C. Next, stirring was performed, and the polymerization reaction was performed for 1 hour while adjusting the polymerization temperature to maintain the polymerization temperature. After the completion of the polymerization reaction, the properties of the polymer were analyzed, and the resultant polymer had Mw of 27714 and Mw/Mn of 2.78.

[Example 7] Put 30 g of MOVE and 0.45 g of bis(2,4,6-trimethylpyridine)-bromonium hexafluorophosphate into a 300 mL flask. The inside of the reaction vessel was shielded from light by covering the flask with aluminum foil. Next, the inside of the reaction system was heated to 70°C. Next, stirring was performed, and the polymerization reaction was performed for 9 hours while adjusting the polymerization temperature to maintain the polymerization temperature. After the polymerization reaction was completed, the properties of the polymer were analyzed, and the resultant polymer had Mw of 1734 and Mw/Mn of 1.52.

[Comparative Example 1] The polymerization was carried out in the same manner as in Example 1 except that the onium salt was not added. As a result, no polymer was produced.

The results of Examples 1 to 7 and Comparative Example 1 are shown in Table 1.

From the results of Examples 1 to 7, by polymerizing vinyl ether monomers under high temperature conditions in the presence of onium salts, various vinyl ether polymers were obtained. Various onium salts were used in the polymerization system this time, and it was confirmed that the polymerization proceeded to produce a polymer under all conditions. On the other hand, from the results of Comparative Example 1, it was confirmed that in the system without addition of onium salt, polymerization did not proceed and no polymer was formed.

[Example 8] Except for further adding 0.4 g of propylene carbonate, polymerization was carried out in the same manner as in Example 1. After the polymerization reaction was completed, the properties of the polymer were analyzed, and the resultant polymer had Mw of 13033 and Mw/Mn of 1.97. In addition, the internal temperature rise in the polymerization system was 3°C.

[Example 9] Except that 1.2 g of propylene carbonate was further added, polymerization was carried out in the same manner as in Example 1. After the polymerization reaction was completed, the properties of the polymer were analyzed, and the resultant polymer had an Mw of 11178 and a Mw/Mn of 1.80. In addition, the internal temperature rise in the polymerization system was 0.5°C.

The results of Examples 1, 8 and 9 are shown in Table 2.

From the results of Examples 8 and 9, it was confirmed that the temperature increase can be controlled by adding propylene carbonate. In addition, it was confirmed that by adjusting the amount of propylene carbonate, the increase in internal temperature and the polymerization rate in the polymerization system can be adjusted.

[Example 10] Except that the onium salt is changed to (4-methylphenyl)[4-(2-methylpropyl)phenyl]-iphonium hexafluorophosphate, and the onium salt and propylene carbonate are in a mass ratio of 3:1 Except for mixing, polymerization was carried out in the same manner as in Example 1. After the completion of the polymerization reaction, the properties of the polymer were analyzed. The Mn of the polymer produced was 9499, Mw was 18544, and Mw/Mn was 1.95.

[Example 11] The polymerization was carried out in the same manner as in Example 10 except that the monomer component was ethylhexyl vinyl ether (EHVE). After the completion of the polymerization reaction, the properties of the polymer were analyzed, and the resultant polymer had an Mn of 2200, Mw of 3447, and Mw/Mn of 1.55.

[Example 12] The polymerization was carried out in the same manner as in Example 10 except that the monomer component was cyclohexyl vinyl ether (CHVE). After the polymerization reaction was completed, the properties of the polymer were analyzed, and the resultant polymer had Mn of 1119, Mw of 1673, and Mw/Mn of 1.50.

[Example 13] The polymerization was carried out in the same manner as in Example 10 except that the monomer component was 2-(2-ethoxyethoxy)ethyl vinyl ether (EOEOVE). After the polymerization reaction was completed, as a result of analyzing the properties of the polymer, the Mn of the polymer produced was 3690, Mw was 7365, and Mw/Mn was 1.99.

[Example 14] The polymerization was carried out in the same manner as in Example 10 except that the monomer component was 2-ethoxyethyl vinyl ether (EOVE). After the polymerization reaction was completed, the properties of the polymer were analyzed, and the resultant polymer had Mn of 1107, Mw of 1913, and Mw/Mn of 1.73.

[Example 15] The polymerization was carried out in the same manner as in Example 10 except that the monomer component was triethylene glycol monomethyl vinyl ether (TEGVE). After the completion of the polymerization reaction, the properties of the polymer were analyzed. The Mn of the polymer produced was 3667, Mw was 5769, and Mw/Mn was 1.57.

The results of Examples 10-15 are shown in Table 3.

From the results of Examples 10-15, it was confirmed that the polymerization system this time can be applied to various vinyl ether monomers with different side chain structures.

Claims (10)

A method for producing vinyl ether polymers, which includes only the following general formula (1):

(In the formula, R ¹ represents an alkyl group with a carbon number of 1 to 3, and n is an integer of 1 to 10) as a monomer, and an onium salt is used as a polymerization initiator. It is made by polymerization step without solvent. The production method according to claim 1, wherein the onium salt is at least one selected from the group consisting of iodonium salt, oxonium salt, sulphur salt, and bromium salt. The manufacturing method of claim 1 or 2, wherein the amount of the onium salt is in the range of 0.1 to 15% by mass relative to the total amount of the vinyl ether monomer. The manufacturing method of claim 1 or 2, wherein in the aforementioned polymerization step, a cyclic carbonate is further used. The manufacturing method of claim 4, wherein the aforementioned cyclic carbonate is propylene carbonate. The manufacturing method of claim 1 or 2, wherein the polymerization temperature in the aforementioned polymerization step is 20°C or higher. According to the manufacturing method of claim 1 or 2, wherein the weight average molecular weight of the aforementioned vinyl ether polymer is in the range of 1,000 to 50,000. A method for manufacturing a vinyl ether polymer, which includes using only methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl Ether, sec-butyl vinyl ether, isobutyl vinyl ether, tert-butyl vinyl ether, n-pentyl vinyl ether, n-hexyl vinyl ether, n-heptyl vinyl ether, n- Octyl vinyl ether, ethylhexyl vinyl ether, n-nonyl vinyl ether, n-decyl vinyl ether, cyclohexyl vinyl ether, tricyclodecyl vinyl ether and phenyl vinyl ether At least one of the group of vinyl ether monomers is used as a monomer, and an onium salt is used as a polymerization initiator, and one selected from the group consisting of ethylene carbonate, propylene carbonate, and butyl carbonate At least one kind of cyclic carbonate is formed by polymerization step without solvent. A method for producing vinyl ether polymer, which includes the following general formula (1):

(In the formula, R ¹ represents an alkyl group with 1 to 3 carbons, and n is an integer of 1 to 10) at least one of the vinyl ether monomers, using onium salt as a polymerization initiator, in the absence of solvent, It is formed by the step of light-shielding polymerization. A method for producing a vinyl ether polymer, which contains a compound selected from methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether , Sec-butyl vinyl ether, isobutyl vinyl ether, tert-butyl vinyl ether, n-pentyl vinyl ether, n-hexyl vinyl ether, n-heptyl vinyl ether, n-octyl Vinyl ether, ethylhexyl vinyl ether, n-nonyl vinyl ether, n-decyl vinyl ether, cyclohexyl vinyl ether, tricyclodecyl vinyl ether and phenyl vinyl ether At least one of the group of vinyl ether monomers, using an onium salt as a polymerization initiator, and at least a cyclic carbonate selected from the group consisting of ethylene carbonate, propylene carbonate, and butyl carbonate One type, made by the step of polymerization under light-shielding without solvent.