Method for producing hydroxyl group-containing vinyl ether polymer

Abstract

A method for producing a hydroxyl group-containing vinyl ether polymer according to the present invention includes: a step of radical polymerizing at least one vinyl ether selected from vinyl ether having a hydroxyl group represented by the following formula (2): ##STR00001## wherein R.sup.7 represents an alkylene group which is straight-chained, branched or comprises an alicyclic structure, and p is 1, 2, or 3, in the presence of water as a polymerization solvent and an azo compound represented by the following formula (1) as a polymerization initiator: ##STR00002## wherein R.sup.1 to R.sup.4 each independently represent a hydrogen atom or an alkyl group and R.sup.5 and R.sup.6 each independently represent an alkoxy group optionally having a substituent group or an alkyl amino group optionally having a substituent group.

Claims

1. A method for producing a hydroxyl group-containing vinyl ether polymer, comprising: a step of radical polymerizing at least one vinyl ether selected from vinyl ether having a hydroxyl group represented by the following formula (2): ##STR00009## wherein R.sup.7 represents an alkylene group which is straight-chained, branched or comprises an alicyclic structure, and p is 1, 2, or 3, in the presence of water as a polymerization solvent and dimethyl 2,2-azobis (2- methylpropionate) as a polymerization initiator, and the amount of said dimethyl 2,2-azobis (2-methylpropionate) added is from 0.01 to 0.5 mol % based on said vinyl ether, wherein the monomer conversion rate is 95% or more in the step of radical polymerization.

2. The method for producing a polymer according to claim 1, wherein the monomer conversion rate is 99% or more in the step of radical polymerization.

3. The method for producing a polymer according to claim 1, wherein the amount of said dimethyl 2,2-azobis(2-methylpropionate) added is from 0.01 to 0.2 mol % based on said vinyl ether and the number average molecular weight Mn of the hydroxyl group-containing vinyl ether polymer is from 10,000 to 600,000.

4. A method for producing an aqueous hydroxyl group-containing vinyl ether polymer solution comprising water and a hydroxyl group-containing vinyl ether polymer, the method comprising: a step of radical polymerizing at least one vinyl ether selected from vinyl ether having a hydroxyl group represented by the following formula (2): ##STR00010## wherein R.sup.7 represents an alkylene group which is straight-chained, branched or comprises an alicyclic structure, and p is 1, 2, or 3, in the presence of water as a polymerization solvent and dimethyl 2,2-azobis(2-methylpropionate) as a polymerization initiator, and the amount of said dimethyl 2 2-azobis (2-methylpropionate) added is from 0.01 to 0.5 mol % based on said vinyl ether, wherein the monomer conversion rate is 95% or more in the step of radical polymerization; and a step of storing the obtained hydroxyl group-containing vinyl ether polymer in an aqueous solution.

5. The method for producing an aqueous polymer solution according to claim 4, wherein the monomer conversion rate is 99% or more in the step of radical polymerization.

6. The method for producing an aqueous polymer solution according to claim 4, wherein the amount of said dimethyl 2,2-azobis(2-methylpropionate) added is from 0.01 to 0.2 mol % based on said vinyl ether and the number average molecular weight Mn of the hydroxyl group-containing vinyl ether polymer is from 10,000 to 600,000.

Description

EXAMPLES

(1) The present invention will be described in more detail below by way of the examples and comparative examples; however the present invention is not interpreted by being limited to the content of the following examples.

(2) Evaluation of the physical property of polymers that were obtained in the Examples was carried out by the following methods.

(3) (1) Calculation of the monomer conversion rate (residual amount) and structure analysis of polymer were carried out using .sup.1H NMR (JNM ECX-500II, manufactured by JEOL Ltd.) (solvent: heavy water or heavy chloroform). The value of the residual amount of the monomers is the value measured before undergoing the step of removing the monomers.

(4) (2) Analysis of weight average molecular weight (Mw) and molecular weight distribution (Mw/Mn) was carried out using gel permeation chromatography (GPC).

(5) Analysis Condition

(6) Column: TSK gel column G-MHHR-M x2 (manufactured by Tosoh Corporation) or Shodex GPC KD804 x3 (manufactured by Showa Denko K. K.)

(7) Solvent: dimethylformamide (containing 10 mmol/L lithium bromide)

(8) Measurement temperature: 40 C.

(9) Flow rate: 1.0 ml/min

(10) Standard curve: standard polystyrene standard

Example 1

Production of poly(2-hydroxyethyl vinyl ether) (1)

(11) To a test tube, a stirring bar, 500 parts by mol of 2-hydroxyethyl vinyl ether (hereinafter, referred to as HEVE) as a monomer, and 1 mol (0.2 mol % based on a monomer) of MAIB (manufactured by Wako Pure Chemical Industries, Ltd., product name V-601) as a radical polymerization initiator were added, and further, water was added as a polymerization solvent so that the HEVE concentration will be 50 mass %, and they were well dissolved. Then, nitrogen was blown through the test tube to deoxidize. After deoxidization, the test tube was sealed and the polymerization reaction was started in an oil bath of 70 C. After 48 hours, the polymerization was terminated by cooling and exposing to air, and .sup.1H NMR analysis and GPC analysis were carried out. As a result, the monomer conversion rate was 99% or more, the number average molecular weight Mn of the obtained polymer was 33900, and the molecular weight distribution Mw/Mn was 2.45 after an elapse of 48 hours.

Example 2

Production of poly(2-hydroxyethyl vinyl ether) (2)

(12) Polymerization reaction was carried out with the similar operation as Example 1 except that water was added so that the HEVE concentration will be 20 mass %. As a result, the monomer conversion rate was 99% or more, the number average molecular weight Mn of the obtained polymer was 10700, and the molecular weight distribution Mw/Mn was 1.59 after an elapse of 48 hours.

Example 3

Production of poly(2-hydroxyethyl vinyl ether) (3)

(13) Polymerization reaction was carried out with the similar operation as Example 1 except that 2,2-azobis[2-methyl-N-(2-hydroxylethyl) propionamide (manufactured by Wako Pure Chemical Industries, Ltd., product name V-086) was used as a radical polymerization initiator. As a result, the monomer conversion rate was 99% or more, the number average molecular weight Mn of the obtained polymer was 11400, and the molecular weight distribution Mw/Mn was 1.94 after an elapse of 93 hours.

Example 4

Production of poly(4-hydroxybutyl vinyl ether) (1)

(14) Polymerization reaction was carried out with the similar operation as Example 1 except that 4-hydroxylbutyl vinyl ether was used as a monomer. As a result, the monomer conversion rate was 99% or more, the number average molecular weight Mn was 15500, and the molecular weight distribution Mw/Mn was 2.20 after an elapse of 48 hours.

Example 5

Production of poly(l,4-cyclohexanedimethanol monovinyl ether)

(15) Polymerization reaction was carried out with the similar operation as Example 1 except that 1,4-cyclohexanedimethanol monovinyl ether was used as a monomer. As a result, the monomer conversion rate was 81%, the number average molecular weight Mn of the obtained polymer was 12300, and the molecular weight distribution Mw/Mn was 1.89 after an elapse of 48 hours.

Example 6

Production of poly(diethylene glycol monovinyl ether)

(16) Polymerization reaction was carried out with the similar operation as Example 1 except that diethylene glycol monovinyl ether (hereinafter, referred to as DEGV) was used as a monomer. As a result, the monomer conversion rate was 99% or more, the number average molecular weight Mn of the obtained polymer was 12600, and the molecular weight distribution Mw/Mn was 2.10 after an elapse of 48 hours.

Example 7

Production of poly(2-hydroxylethyl vinyl ether) (4)

(17) Polymerization reaction was carried out with the similar operation as Example 1 except that the amount of MAIB added was 0.1 mol % based on a monomer. As a result, the monomer conversion rate was 60% or more after an elapse of 48 hours, and when the polymerization was further continued, the monomer conversion rate became 99% or more after an elapse of 96 hours. The number average molecular weight Mn of the obtained polymer was 35500, and the molecular weight distribution Mw/Mn was 1.74.

Comparative Example 1

Production of poly(2-hydroxyethyl vinyl ether) (5)

(18) Polymerization reaction was carried out with the similar operation as Example 1 except that toluene was used as a polymerization solvent. As a result, the monomer conversion rate was 49%, the number average molecular weight Mn of the obtained polymer was 18900, and the molecular weight distribution Mw/Mn was 1.68 after an elapse of 24 hours.

Comparative Example 2

Production of poly(2-hydroxyethyl vinyl ether) (6)

(19) Polymerization reaction was carried out with the similar operation as Example 1 except that 2-propanol was used as a polymerization solvent. As a result, the monomer conversion rate was 31%, the number average molecular weight Mn of the obtained polymer was 15800, and the molecular weight distribution Mw/Mn was 1.55 after an elapse of 24 hours.

Comparative Example 3

Production of poly(2-hydroxyethyl vinyl ether) (7)

(20) Polymerization reaction was carried out with the similar operation as Example 1 except that ethylene glycol was used as a polymerization solvent. As a result, the monomer conversion rate after an elapse of 24 hours was 71% but polyacetal was generated in 60%. The number average molecular weight Mn of the obtained polymer was 10100, and the molecular weight distribution Mw/Mn was 1.73.

Comparative Example 4

Production of poly(4-hydroxyethyl vinyl ether) (8)

(21) Polymerization reaction was carried out with the similar operation as Example 1 except that 1,4-butanediol was used as a polymerization solvent. As a result, the monomer conversion rate after an elapse of 24 hours was 69% but polyacetal was generated in 40%. The number average molecular weight Mn of the obtained polymer was 9500, and the molecular weight distribution Mw/Mn was 1.79.

Comparative Example 5

Production of poly(4-hydroxybutyl vinyl ether) (2)

(22) Polymerization reaction was carried out with the similar operation as Example 4 except that 2,2-azobisisobutyronitrile (manufactured by Wako Pure Chemical Industries, Ltd., product name V-60, hereinafter referred to as AIBN) was used as a radical polymerization initiator. As a result, the monomer conversion rate was 37%, the number average molecular weight Mn of the obtained polymer was 29400, and the molecular weight distribution Mw/Mn was 1.73 after an elapse of 48 hours.

Comparative Example 6

Production of poly(4-hydroxybutyl vinyl ether) (3)

(23) To a glass vessel with a three-way cock, 68.25 g (587.6 mmol) of HBVE and 17.82 g of methanol was added and heated, and a solution in which 1.3393 g (5.82 mmol, 1 mol % based on a monomer) of MAIB was dissolved in 11.91 g of methanol was added drop wise over 1 hour after the internal temperature reached to 70 C. Then, stirring was carried out for 8 hours at 70 C. 70.58 g of methanol was added and the content was cooled down to room temperature, and extraction was carried out three times with 168.8 g of hexane to remove the residual monomers and the polymerization initiator residues. Then, the solvent was removed under reduced pressure to obtain poly(4-hydroxybutyl vinyl ether). As a result, the monomer conversion rate was 56.7%, the number average molecular weight Mn of the obtained polymer was 32000, and the molecular weight distribution Mw/Mn was 1.35.

Comparative Example 7

Production of poly(4-hydroxybutyl vinyl ether) (4)

(24) Polymerization reaction was carried out with the similar operation as Comparative Example 6 except that the amount of MAIB used was changed to 5 mol % based on a monomer. As a result, the monomer conversion rate was 91.67%, the number average molecular weight Mn of the obtained polymer was 34000, and the molecular weight distribution Mw/Mn was 1.24.

Example 8

Production of poly(4-hydroxybutyl vinyl ether) (5)

(25) To a glass vessel with a three-way cock, 90 g of water, 90 g (774 mmol) of HBVE, 29.7 g (129 mmol, 16.7 mol % based on the total amount of monomers) of MAIB were introduced and heated at 70 C., then the polymerization was carried out for 10 hours under stirring. After cooling down to room temperature, water and light components were removed by evaporation to obtain poly(4-hydroxybutyl vinyl ether) of interest. The HBVE conversion rate was 99% or more, the number average molecular weight Mn of the obtained polymer was 3090, and the molecular weight distribution Mw/Mn was 2.40.

Example 9

Production of poly(4-hydroxybutyl vinyl ether) (6)

(26) Polymerization reaction was carried out with the similar operation as Example 8 except that the amount of MAIB added was 3 mol % based on a monomer. As a result, the HBVE conversion rate was 89%, the number average molecular weight Mn of the obtained polymer was 5910, and the molecular weight distribution Mw/Mn was 1.78.

Example 10

Production of 4-hydroxylbutyl vinyl ether/diethylene glycol monovinyl ether copolymer (1)

(27) To a glass vessel with a three-way cock, 90 g of water, 71.9 g (619 mmol) of HBVE, 20.6 g (156 mmol) of DEGV, 29.7 g (129 mmol, 16.6 mol % based on the total amount of monomers) of MAIB were introduced and heated at 70 C., then the polymerization was carried out for 10 hours under stirring. After cooling down to room temperature, water and light components were removed by evaporation to obtain a HBVE/DEGV copolymer of interest. The HBVE C was 99.6%, the DEGV conversion rate was 94.2%, the number average molecular weight Mn of the obtained polymer was 3160, and the molecular weight distribution Mw/Mn was 2.13.

(28) TABLE-US-00001 TABLE 1 Polymerization Initiator Monomer Polymer Added Residual Number average molecular weight Polymerization Amount Amount molecular weight distribution Solvent Type (mol %) Type (mol %) Mn Mw/Mn Example 1 water MAIB 0.2 HEVE Less than 1 33900 2.45 Example 2 water MAIB 0.2 HEVE Less than 1 10700 1.59 Example 3 water V-086 0.2 HEVE Less than 1 11400 1.94 Example 4 water MAIB 0.2 HBVE Less than 1 15500 2.20 Example 5 water MAIB 0.2 CHDMVE 19 12300 1.89 Example 6 water MAIB 0.2 DEGVE Less than 1 12600 2.10 Example 7 water MAIB 0.1 HEVE Less than 1 35500 1.74 Comparative toluene MAIB 0.2 HEVE 51 18900 1.68 Example 1 Comparative 2-propanol MAIB 0.2 HEVE 69 15800 1.55 Example 2 Comparative Ethylene MAIB 0.2 HEVE 29 10100 1.73 Example 3 glycol Comparative 1,4-butanediol MAIB 0.2 HEVE 31 9500 1.79 Example 4 Comparative water AIBN 0.2 HBVE 63 29400 1.73 Example 5 Comparative methanol MAIB 1 HBVE 43.3 32000 1.35 Example 6 Comparative methanol MAIB 5 HBVE 8.33 34000 1.24 Example 7 Example 8 water MAIB 16.7 HBVE Less than 1 3090 2.40 Example 9 water MAIB 3 HBVE 11 5910 1.78 Example 10 water MAIB 16.6 HBVE/DEGVE 0.4/5.8 3160 2.13