JPH0286603A - Production of water-soluble high-molecular-weight polymer - Google Patents

Abstract

PURPOSE:To prepare a water-sol. high-MW vinyl polymer economically and effectively, by polymerizing a water-sol. vinyl monomer using a specific redox catalyst as a polymerization initiator. CONSTITUTION:A water-sol. vinyl monomer is polymerized using a redox catalyst comprising a difunctional org. peroxide and a reducing agent as a polymerization initiator. At least one of compounds of formula I [wherein R1, R2, R4 and R5 are each independently H, methyl, ethyl or propyl; R3 is a single bond, formula II (n is 1-3) or phenylene] and formula III (wherein R6 and R7 are each independently H, methyl, ethyl or propyl) is used as the difunctional org. peroxide, while the reducing agent may be one usually used in a redox system, and both aqueous solution polymerization and water-in-oil emulsion polymerization can be used.

Description

[Detailed Description of the Invention] [Field of Industrial Application]] The present invention relates to a method for producing a water-soluble polymer used in the fields of polymer flocculants, thickeners, oil recovery agents, papermaking aids, etc. More specifically, the present invention relates to a method for efficiently producing a high molecular weight water-soluble polymer from a water-soluble vinyl monomer using a specific polymerization initiator.

[Prior Art] Among the water-soluble polymers used as polymer flocculants, oil recovery polymers, papermaking aids, etc., those with particularly high molecular weights are preferred because they exhibit excellent effects.

Conventionally, as a method for producing 1 q of high molecular weight polymer from water-soluble vinyl monomer 1, for example, from an acrylic yarn, a method has been adopted in which a method of reducing the amount of catalyst used in an aqueous solution and a method of polymerizing at a low monomer concentration have been adopted. There is.

However, the method of reducing the amount of catalyst has the disadvantage that as the polymerization time becomes longer, an insoluble polymer is produced and the water solubility becomes poor. In addition, in the method of lowering the heptamer concentration, the polymerization time becomes longer, and at the same time, it is necessary to isolate small polymers and remove a large amount of solvent and dry them when producing a granular product. Therefore, the production capacity decreases and the production cost increases due to the drying process.

A method has also been adopted in which a water-soluble polymer is obtained by polymerizing a water-soluble monomer aqueous solution in a water-insoluble solvent containing a surfactant and a catalyst in a water-in-oil emulsion system. A similar problem exists when trying to obtain a polymerization, which has disadvantages in that the polymerization time is long and the product concentration is low at the same time, which is economically disadvantageous.

[Problems to be Solved by the Invention] Therefore, the problem to be solved by the present invention is to obtain a vinyl monomer polymer with high molecular weight and good water solubility. The present invention aims to provide a production method for efficiently producing a high molecular weight water-soluble vinyl polymer by eliminating the drawbacks of the conventional methods of lowering the cos.

[Means for Solving the Problems] In order to solve the above problems, the present inventors have continued to study various methods for producing water-soluble high molecular weight vinyl polymers, and as a result, they have discovered that bifunctional organic peroxides and ) By using a redox catalyst in combination with a bulking agent as a polymerization initiator, we have discovered that it is possible to obtain a polymer with a higher molecular weight and better water solubility in a shorter polymerization time than with conventional methods. Completed the invention.

[Contingency of invention 1 Hereinafter, the configuration of the present invention will be explained in detail.

Water-soluble vinyl monomer The water-soluble vinyl monomer to be subjected to the small polymerization method in the present invention is a vinyl monomer that is itself water-soluble and produces a water-soluble polymer upon polymerization, and has a water-soluble substituent group. This applies to nanatsuma and its salts.

Specific examples include (meth)acrylamide, N.

N-dimethylacrylamide, (meth)acrylic acid, 2
-acrylamido-2-methylpropanesulfonic acid, vinylsulfonic acid, styrenesulfonic acid, itaconic acid, 2
-(meth)acryloyloxydimethyldimethylammonium, 3-(meth)-acryloyloxypropyldimethylammonium, 3-(meth)acryloyloxy-2-hydroxypropyldimethylammonium, 3-(meth)
Acrylamide jlopyldimethylammonium, 2~(
Examples include meth)-acryloylaminoedildimethylammonium, 3-(meth)-acryloylamino-2-j droxypropyldimethylammonium, and dimethyldiallylammonium chloride.

Regarding the types of salts of water-soluble vinyl monomers, anionic monomers include gold salts such as sodium and potassium, cod salts, and ammonium salts, and cationic monomers include methyl chloride quaternary salt, dimethyl sulfate quaternary salt, and hensyl chloride quaternary salt. salts, tertiary sulfuric acid salts, tertiary hydrochloric acid salts, and the like.

These seven polymers can be used alone, or two or more types can be used in combination if commercially available since 1q of polymers are water-soluble. For example, a combination of a cationic monomer and an anionic monomer that results in an amphoteric polymer is also possible as long as the solubility of the polymer is not impaired.

Other monomers Furthermore, other monomers that can be copolymerized with the above monomers can also be used in combination. However, the amount of other additives used must be within a range that does not impair the water solubility of the polymer. Examples of such monomers include (meth)acrylonitrile, (meth)acrylic acid ester, and styrene.

Polymerization initiator The polymerization initiator used in the method of the present invention is a redox initiator that is a combination of a difunctional organic peroxide and a reducing agent.

Trifunctional [(■Organic peroxide has the following formula (I>HOO-(
, -R3-C-00H(I)R2R5 [wherein R, R2, R4 and R5 are each independently hydrogen, methyl group, ethyl group or butyl group, R3 is a single bond, -+Cl-12-CH2
-)-, a group (in the group, n is an integer of 1 to 3), or a phenylene group. ] and the following formula (II) [wherein R6 and R7 are mutually independent and -(
, hydrogen, methyl group, 1-pu group or propyl group.

] is selected from one or more of the compounds shown below.

As a specific example, 2.5] - Jimeburu \ Kirin? , 5
-Cybidroba-oxide, diisopropylbenzenedihydroperoxylide, cyclohexanone peroxide, methylcyclohexylone peroxide,
and the like.

These are known compounds and are commercially available or
Alternatively, it can be manufactured by a known method. In the present invention, these compounds can be used not only in a purified state but also in products containing impurities such as hydroxides.

Song M1 is used as a reducing agent in redox systems.
sodium acid, potassium hydrogen sulfate, potassium sulfite,
Piro Kano! Sodium L acid, ferrous m11 acid, 3-treated amine, etc. are used.

The amount of peroxide and reducing agent added is usually about 0.0001 to 0.1% by weight each, preferably 0.
．． 001 to 0.05 Φ early% is desirable.

In the method of this defense, bifunctional 4\i■ peroxide and reducing agent are used to convert 1 to tux-based starting β) 1 to oxidation, which is a conventionally used initiator, to 11, monofunctional organic peroxide. things and/
Alternatively, it may be used in combination with an azo catalyst.

A specific example of an oxidizing agent is perrlI! t M potassium, ammonium persulfate, hydrogen peroxide, tool i-lebutylhyde [1 peroxinite etc., 2.2' azohis-2-amidinopropane hydrochloride as an azo catalyst,
2,2'-Azobis-2-(5-methyl-2-imidacillin-2-yl)propane hydrochloride, 2,2'-Azohisisobutyronitrile, 2゜2'-Azohis-(2,4-
dimethylvaleronitrile), etc.

1 Polymerization method 1 As a method for preparing the above-mentioned seven polymers according to the present invention,
There are aqueous solution polymerization methods and water-in-oil emulsion methods.

Aqueous solution polymerization method After dissolving the above monomer in water and adding additives such as a chain transfer agent and a chelating agent as necessary, the solution is purged with an inert gas such as nitrogen to remove oxygen. The concentration of the above-mentioned monomer depends on the type of monomer, but is 10 to 80 Wτ%, preferably 25 to 70%.

The procedure is to heat the degassed monomer solution to -10 to 20'C.
After cooling, preferably to -5 to 10°C, a reducing agent aqueous solution and an organic peroxide solution are added to and mixed with the monomer aqueous solution to initiate polymerization.

Organic peroxides usually do not dissolve in water, so they are dissolved in a small amount of organic solvent and added. The organic solvent used is selected from methanol, ethanol, isopropanol, etc.

Polymerization typically begins with an induction period of several minutes to an hour, and the temperature increases. Polymerization is carried out under heat insulation or cooling. Usually 1
After about 7 hours, the exotherm ends and the polymerization is completed, yielding the desired high molecular weight water-soluble polymer.

The polymer is in the form of a gel, and after being crushed by ordinary physical means, a cutting mill, a meat chopper, or other means, it is dried. After drying to a moisture content of approximately 10%, it is further crushed to obtain a product with a uniform particle size. .

Water-in-oil emulsion polymerization The initiator system according to the invention can also be used in water-in-oil emulsion polymerization.

As a method, first, an aqueous solution of 7-mer is prepared, and a difunctional organic peroxide dissolved in an organic solvent such as alcohol is added thereto. On the other hand, a water-insoluble organic solvent containing a surfactant is separately prepared, the above aqueous solution is dispersed in this, and the emulsification is carried out using a homocyliner or the like to a particle size of about 0.3 to 20 μm in diameter.

This emulsion is purged with an inert gas such as nitrogen to remove oxygen. The same monomers as those used in the aqueous solution polymerization method can be used as the polymerizable polymer.The aperture degree varies depending on the type of monomer, and is preferably 30 to 7 Qwt%.

As water-insoluble organic solvents, aliphatic, alicyclic or aromatic hydrocarbons, chlorinated hydrocarbons and the like commonly used in reverse phase polymerization can be used alone or in combination.

As the emulsifying surfactant, one having an HLB value of 4-6 is used. Examples include sorbitan monostearate, sorbitan monooleate, glyceryl monooleate, and ethoxylated aliphatic alcohols.

The amount of water-in-oil emulsifier used is usually: 0.1-1Qwt% of a small amount of E-summer aqueous solution, and 05-5wt. Wow, I'm so happy.

The weight of the continuous phase for the dispersed aqueous solution is 1-
4) q or usually 2 to 3 is preferred.

The difunctional organic peroxide according to the invention typically contains o, ooi to 0.5 wt%, preferably 0, based on the vinyl monomer.
．． 0.005 to 0.10 wt% is added.

The peroxide is dissolved in an organic solvent such as alcohol and added to the aqueous solution before emulsification or the emulsion after emulsification.

Polymerization is usually initiated by adding an aqueous reducing agent solution. The incompatibility temperature is not particularly limited, but is usually 20 to 70'C, preferably 30 to 60'C. The reaction temperature is usually kept constant by cooling.

The reaction rate of polymerization can be tracked and measured in various ways.

For example, a method of analyzing two-handed bonds during polymerization can be easily used. After the polymerization is completed, add 7 JO of a surfactant to promote water dispersibility, if necessary. The added ham is usually O65-7%, preferably 1-3% by weight, based on the emulsion.

[Effects of the Invention] According to the method for polymerizing water-soluble vinyl monomers of the present invention, a polymer with a higher molecular weight and better water solubility than before can be obtained, which was not possible with conventional techniques, and has an economically unparalleled effect. can get.

[Example 1] The present invention will be further explained with reference to the following examples. However, the present invention is not limited to the following examples.

Example 1 Acrylamide/sodium acrylate (molar ratio 80/20
) was placed in an I Ky insulated glass bottle, purged with nitrogen, and cooled to 0°C. to this,
Dissolve 0.005 g of 2,5-dimethylhexane-2゜5-civitro oxide in 1 mj of metal, and dissolve 0.005 g of sulfite in 1 m of water.
The solution was dissolved in IJ (IJ) and stirred.

Polymerization started immediately and reached the maximum temperature after 65 minutes.

After the polymerization is completed, take out the gel and cut it into 2-3 m with a cutter.
Grind to a particle size of m and dry at 60'C to 100°O. P.I.
Dry with M and crush this to make a powder product. (The water solubility and intrinsic viscosity of the obtained polymer were measured by the following method.

1) Prepare a water-soluble 20.1% distilled aqueous solution, filter it through a wire mesh, and visually judge the evaluation criteria: ○...no insoluble matter △...slightly insoluble matter X...insoluble matter countless numbers 2) [η]: Intrinsic viscosity Table 1 shows the results of measurement using an Ubbelohde viscometer at 30°C in 1N NaNO3 solution.

Example 2 2゜2' - to 1 kg of monomer aqueous solution similar to Example 1
Add 0.3 g of azobis-2-amidinopropane hydrochloride and place it in an insulated glass bottle, purge with nitrogen, and lower the temperature to O'
Cooled to C. To this, diisopropylbenzene dihydroperoxide 0.0017 was added to methanol 1 m (l
A solution of 0.0019 potassium persulfate dissolved in water, and a solution of 5A ferrous acid 010029 dissolved in 1 ml of water were added and stirred. Polymerization starts immediately and 75
The maximum temperature was reached within minutes.

After the polymerization was completed, the powdered polymer was prepared in the same manner as in Example 1, and its physical properties were measured.

The results are shown in Table 1.

Comparative Example 1 In the same manner as in Example 2, 0.002 g of potassium persulfate was dissolved in 1 d of water and 0.002 g of 5A ferrous acid instead of adding a methanol solution of Ninomiya oxide. g dissolved in 1 ml of water was added and stirred.

Polymerization started immediately and reached maximum temperature after 140 minutes. In the same manner as in Example 2, one sample of powdered polymer was measured at (q).

The results are shown in Table 1.

Example 3 Acrylamide 75.6'J, Acrylic 1118.9
9 was placed in a parallel flask with an internal volume of 500 mβ, and dissolved in 118 g of ion-exchanged water. While stirring to keep the internal temperature below 40'C, granular NaOH 10,59 was added for neutralization.

To this was added a solution of 0.029 ml of 2,5-dimethylhexane-2,5-sivitro-oxynite dissolved in 0.1 ml of metal chloride.

On the other hand, an oil phase was prepared by dissolving Span 80 (sorbitan monooleate) 8.97 in linear aliphatic hydrocarbon 569, and the above aqueous solution-E-Zumer phase was emulsified into this, followed by nitrogen aeration for 1 hour. After removing dissolved oxygen, the internal temperature was maintained at 40'C, and 0.0% was added as a reaction initiator.
Polymerization was carried out while adding a 5% aqueous sodium sulfite solution. The reaction rate of polymerization was tracked by analyzing double bonds, and the reaction was terminated when a reaction rate of 99.5% or higher was confirmed. The polymerization time was 1 hour and 40 minutes. After the polymerization was completed, 5 q of nonylphenol ethylene oxide adduct was added to improve water dispersibility.

emulsion polymer (polymer content 34.
3wt%) was dissolved to form a distilled water aqueous solution having a polymer content of 0.1%, and the water solubility and intrinsic viscosity were measured in the same manner as in Example 1.

The results are shown in Table 2.1゜Example 4 Using the same method as in Example 3, 0.015 g of cyclohexF nanoperoxinite was added as Ninomiya functional peroxide.
17! The solution dissolved in acetone was added to the aqueous phase, and Φ combination was carried out in the same manner as in Example 3. (0.5% Φ!TnIiJ!SiM potassium was used as a reducing agent. The polymerization time was 2 hours. Same as Example 3), and the physical properties were measured in a hill.

The results are shown in Table 2.

Comparative Example 2 In the same manner as in Example 3, tert-butyl hydroperoxide 0.02
A solution of 9 in 0.1M aretone was added to the aqueous phase, and polymerization was carried out in the same manner as in Example 3.

Polymerization time is 2,5)1. 'It was for one hour. Example 3
Similarly, 3 measurements were taken of '1'.

The results are shown in Table 2.

Claims (1)

[Claims] 1) A method for producing a water-soluble high molecular weight polymer, which comprises polymerizing a water-soluble vinyl monomer using a redox catalyst in which a difunctional organic peroxide and a reducing agent are combined as a polymerization initiator. . 2) The difunctional organic peroxide has the following formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) [In the formula, R_1, R_2, R_4 and R_5 are independent of each other, and hydrogen , a methyl group, an ethyl group, or a propyl group, and R_3 is a single bond, a ▲ mathematical formula, chemical formula, table, etc. ▼ group (in the group, n is an integer of 1 to 3), or a phenylene group. ] and the following formula (II) ▲ Numerical formulas, chemical formulas, tables, etc. ▼ (II) [In the formula, R_6 and R_7 are independent of each other and are hydrogen, a methyl group, an ethyl group, or a propyl group. The manufacturing method according to claim 1, wherein the manufacturing method is selected from one or more compounds represented by the following. 3) The method according to claim 1 or 2, wherein the water-soluble vinyl monomer is polymerized in an aqueous solution. 4) The method according to claim 1 or 2, wherein the water-soluble vinyl monomer aqueous solution is suspended or emulsified in a water-insoluble organic solvent and then polymerized.