JPH03124712A - Production of fumaric acid copolymer - Google Patents

Abstract

PURPOSE:To obtain economically a fumaric acid copolymer having a low molecular weight and a narrow molecular weight distribution and being useful as a water treatment or a detergent additive by polymerizing a monomer mixture of fumaric acid with another water-soluble unsaturated monomer in an aqueous medium under specified conditions. CONSTITUTION:A process for polymerizing a monomer component comprising 30-70wt.% fumaric acid and 70-30wt.% another water-soluble unsaturated monomer in an aqueous medium, wherein the following conditions are adopted. 0.5-500ppm, based on the monomer component, of at least one kind of metallic ions selected from among a V-containing ion, an Fe ion and a Cu ion is added, 3-100g (based on 1mol of the monomer component) of hydrogen peroxide is used, and the pH during the polymerization is below 2. The water-soluble unsaturated monomer is not particularly limited. As the aqueous medium, water is particularly desirable.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing fumaric acid copolymers useful as water treatment agents, detergent builders, various chelating agents, and the like.

Specifically, the present invention relates to a method for efficiently producing an acid copolymer of Tsuma 2, which has a narrow molecular weight distribution (also has excellent ability to capture metal ions), in an aqueous medium.

[Prior Art J] Fumaric acid copolymers have been used in the fields of, for example, water treatment agents, detergent additives, and various chelating agents. As a known document regarding a method for producing such a fumaric acid copolymer in an aqueous system, JP-A-62-218407 can be mentioned.

However, in the method described in this document, it is necessary to carry out the reaction in a neutralized state with a pH of 2 or more, but under these conditions the reaction does not proceed sufficiently and there is a problem that a large amount of residual monomer remains. Was. In addition, the obtained fumaric acid copolymer also has a wide molecular weight distribution, and is easily gelled by complexing with cations such as Ca ions in water, making it effective as a water treatment agent and detergent additive. It wasn't enough. Furthermore, JP-A-59-12908 describes a method for producing a copolymer of fumaric acid and allyl alcohol, but this method also has the disadvantage that a large amount of residual fumaric acid remains and the molecular weight distribution is wide. It did not solve the problem.

Furthermore, Japanese Patent Publication No. 56-54005 describes a method for producing a fumaric acid copolymer using a monofumarate salt in an aqueous medium, but it is also possible to obtain a polymer with a narrow molecular weight distribution by this method. I could not do it. Also, JP-A-5
No. 6-99212 describes that a fumaric acid/acrylic acid copolymer can be obtained in high yield in a solvent system.

However, this manufacturing method involves polymerization in organic solvents such as toluene and chlorobenzene, which not only requires a large number of steps, but also cannot be said to be an advantageous method from the standpoint of disaster prevention, cost, and resource conservation. . In addition, toluene,
Solvents such as chlorobene remained, posing a safety problem.

Therefore, in aqueous systems, the molecular weight distribution is narrow, and water treatment agents,
There has been a need for a technology to obtain high yields of fumaric acid copolymers useful as detergent additives.

[Problem to be solved by the invention]

The present invention was made in order to solve the problems of the conventional technology, and it is a fumaric acid copolymer with a particularly low molecular weight (and a narrow molecular weight distribution) that is useful as a water treatment agent and a detergent additive. The purpose of this invention is to provide an economical manufacturing method using simple steps.

[Means for Solving the Problems 1] The present invention comprises 30 to 70% by weight of fumaric acid (a) and 70 to 30% by weight of other water-soluble unsaturated monomers (b) (however, fumaric acid (a) and water-soluble When polymerizing the monomer component consisting of (the total amount of the unsaturated monomer (b) is 100% by weight) in an aqueous medium, a vanadium atom content of 0.5 to 500 ppm based on the monomer is added. In the presence of one or more metal ions selected from the group consisting of iron ions, iron ions, and copper ions, 3 to 100 g of hydrogen peroxide (to 1 monomer component) is added as a polymerization catalyst.
mol), and the pH during polymerization is less than 2.

Examples of the aqueous medium that can be used in the present invention include water and a monohydric alcohol having 1 to 4 carbon atoms, or a monohydric alcohol having 3 to 4 carbon atoms.
4 mixed solvents, etc. can be mentioned.

Examples of the alcohol used include methanol,
Ethanol, n-propertool, inpropertool, n
-butanol, imbutanol, 5ec-butanol,
Examples include ter-butanol. Further, examples of the ketone used include acetone, methyl ethyl ketone, and the like.

However, for the purpose of reducing residual monomers and obtaining a fumaric acid copolymer with a narrow molecular weight distribution, the copolymerization is preferably carried out in a completely aqueous system.

In the present invention, the other water-soluble unsaturated monomer (b) used as a copolymerization component of fumaric acid (a) when producing a fumaric acid copolymer is not particularly limited, but for example, acrylic acid , methacrylic acid, α-hydroxyacrylic acid, crotonic acid, and other unsaturated monocarboxylic acid monomers and their salts; maleic acid, itaconic acid, citraconic acid,
Unsaturated polycarboxylic acid monomers such as aconitic acid and their salts: Vinyl acetate; General formula (1) %Formula %(1) (However, in the formula, R1 and R2 each independently represent hydrogen or a methyl group. and R1 and R2 do not simultaneously become a methyl group, R3 represents -CH, -1lCHa)a- or -C(CH3)2-, and R' The total number of carbon atoms in R2 and R3 is 3, Y represents an alkylene group having 2 to 3 carbon atoms, and n is 0 or an integer of 1 to 100. ), for example, 3-methyl-3-butene-
1-ol (isoprenol) 3-methyl-2-buten-1-ol (prenol), 2-methyl-3-buten-2-ol (isoprene alcohol) and ethylene oxide and/or per mole of these monomers. or an unsaturated hydroxyl group-containing monomer such as a monomer to which 1 to 100 moles of propylene oxide are added; general formula (2) % formula % ) (2) (wherein R1 represents hydrogen or a methyl group, a
, b, , d and f are each independently O or 1 to 100
represents an integer of , and a + b + d + f = O ~ 100, -QC, H4- units to 〇 C, H, - units may be combined in any order, and when d + f is O, Z
represents a hydroxyl group, a sulfonic acid group and a ()phosphorous acid group,
Further, when d+f is a positive integer of 1 to 100, Z represents a hydroxyl group. ), for example, 3-allyloxy-
2-hydroxypropanesulfonic acid and its salts; unsaturated (meth)allyl ethers such as glycerol monoallyl ether and monomers with 1 to 100 moles of ethylene oxide and/or propylene oxide added to 1 mole of these monomers; System monomers: vinylsulfonic acid, allylsulfonic acid, methallylsulfonic acid, styrenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, sulfoethyl (meth)acrylate, sulfopropyl (meth)acrylate, 2-hydroxysulfonate Unsaturated sulfonic acid group-containing monomers such as propyl (meth)acrylate and sulfoethylmaleimide, and their salts: Alcohols obtained by adding 0 to 100 moles of ethylene oxide and/or propylene oxide to an alkyl alcohol having 1 to 20 carbon atoms. Monoesters such as (meth)acrylic acid and crotonic acid, monoesters with maleic acid, fumaric acid, itaconic acid, citraconic acid, aconitic acid, etc., salts thereof, and terminal alkyl group-containing esters such as diesters. Saturated monomer: A monoester monomer obtained by adding 1 to 100 moles of ethylene oxide and/or propylene oxide to an unsaturated carboxylic acid monomer such as (meth)acrylic acid or crotonic acid, or maleic acid. A monoester obtained by adding 1 to 100 moles of ethylene oxide and/or propylene oxide to an unsaturated polycarboxylic acid monomer such as acid, fumaric acid, itaconic acid, citraconic acid, aconitic acid, or a salt or diester thereof. Examples include ester type unsaturated monomers such as ester type monomers, and one or more types selected from these groups can be used.

The usage ratio of fumaric acid (a) and other water-soluble unsaturated monomer (b) is 30 to 70% by weight of the former and 70 to 30% by weight of the latter.
It needs to be within the range of When fumaric acid (a) exceeds 70%, residual monomer increases. Fumaric acid (a) is 3
If it is less than 0%, the molecular weight distribution of the obtained fumaric acid copolymer will be broadened.

Next, examples of metal ions used in the present invention include iron ions, vanadium atom-containing ions, and copper ions, among which Fe'', Fe''Cu'' Cu
"V"V"VO""" ■0° is preferable. Particularly preferred metal ions are Fe"Cu" and VO", and one or more selected from the group of these metal ions can be used. It is necessary to use it in the range of 5 to 500 ppm, preferably 5 to 100 ppm.If the amount of metal ions is less than this range, the copolymerization rate will not improve, and the metal If ions are used in amounts greater than this range, they will not only contaminate the product and cause coloring problems, but will also broaden the molecular weight distribution of the fumaric acid copolymer produced, impairing its performance as a water treatment agent and detergent additive. decreases.

There are no particular restrictions on the form of supply of metal ions (in short, they can be used as long as they are ionized within the polymerization reaction system. Examples of such metal compounds include vanadium oxytrichloride, vanadium trichloride, Vanadium, vanadyl oxalate, vanadyl sulfate, vanadate anhydride, ammonium metavanadate, ammonium hybovanadas sulfate [(NH4)2SO, ・VSO4-6HIO], ammonium vanadas sulfate [(NH4)V(SO2), ・12
H20], copper acetate (■), copper bromide (■), copper (II)
Acetyl acetate, cupric ammonium chloride, copper carbonate, copper chloride (■), copper citrate (■), copper formate (■), copper hydroxide (■), copper nitrate, copper naphthenate, copper oleate,
Copper maleate, copper phosphate, copper sulfate (■), cuprous chloride,
Copper (I) cyanide, copper iodide, copper (I) oxide, copper thiocyanate, iron acetylacetate, ferrous ammonium citrate, ferric ammonium oxalate, ferrous ammonium sulfate, ferric ammonium sulfate, citric acid. Water-soluble metal salts such as iron acids, iron fumarate, iron maleate, ferrous lactate, ferric nitrate, iron pentacarbonyl, ferric phosphate, and ferric birophosphate; vanadium pentoxide, copper oxide ( (2) Metal oxides such as ferrous oxide and ferric oxide; Metal sulfides such as copper sulfide (2) and iron sulfide; Other examples include net powder and iron powder.

Furthermore, in order to adjust the concentration of metal ions, for example, condensed phosphoric acids such as birophosphoric acid, hexametaphosphoric acid, and tripolyphosphoric acid; aminocarboxylic acids such as ethylenediaminetetraacetic acid, nitrilotriacetic acid, and diethylenetriaminepentaacetic acid; 1-hydroxyethylidene-1; , 1-diphosphonic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, etc. Organic acids such as malic acid, citric acid, itaconic acid, oxalic acid, crotonic acid, etc. Polyacrylic acid such as polyacrylic acid It is also possible to use a complex forming agent such as a carboxylic acid type in combination with the above metal ion.

The polymerization temperature is 50 to 160°C, more preferably 70 to 1
The temperature range is preferably 60°C for the purpose of shortening the polymerization time. More preferably, the temperature is 85 to 150°C. At temperatures below 50°C, the progress of polymerization may be inhibited. On the other hand, 16
If the temperature exceeds 0°C, a thermal decomposition reaction is expected. The solid content concentration during polymerization can be carried out within a wide range;
A range of 0%, more preferably 30 to 60% is preferable since residual fumaric acid can be further reduced.

It is necessary to carry out the polymerization at a pH of less than 2; pH 1,
More preferably 5 or less. If polymerization is carried out at a pH of 2 or higher, the molecular weight distribution will broaden and the performance as a water treatment agent will not be sufficient.

There are no particular restrictions on the neutralizing basic compound used to maintain the pH below 2 during polymerization, but examples include hydroxides and carbonates of alkali metals such as sodium, potassium, and lithium; ammonia; monomethylamine, diethylamine, and trimethylamine. , monoethylamine, dimethylamine,
Alkylamines such as triethylamine; alkanolamines such as monoethanolamine, jetanolamine, triethanolamine isopropanolamine, and secondary butanolamine; and pyridine.

Furthermore, fumaric acid (a) and other water-soluble monomers (b) are
Of course, it is also possible to use these salts.

In the present invention, hydrogen peroxide is used as a polymerization catalyst. The amount of hydrogen peroxide used in the present invention is 1 monomer component.
It is necessary to use 3 to 100 g per mole, a more desirable range is 8 to 80 g, and a most preferred range is 11 to 50 g per mole of monomer component. When hydrogen peroxide is less than 3 g, the amount of residual monomer increases.

On the other hand, if more than 100 g is used, not only will the effect commensurate with the increased amount of hydrogen peroxide not be obtained (it will also cause the problem of hydrogen peroxide remaining in the product).

There are no particular restrictions on the method of supplying hydrogen peroxide into the polymerization system, and for example, hydrogen peroxide may be initially charged into the reaction system, or it may be continuously introduced during the reaction. Depending on the case, it may be possible to divide it and add it. However, in order to make the polymerization reaction proceed more smoothly, continuous addition is preferable.

In the present invention, polymerization catalysts other than hydrogen peroxide, such as persulfates such as ammonium persulfate, sodium persulfate, and potassium persulfate: 2,2'-azobis(2-amidinopropane) hydrochloride, 4,4°-azobis-4 -cyanovaleric acid, azobisisobutyronitrile, 2.2°-azobis(
Azo compounds such as 4-methoxy-2,4-dimethylvaleronitrile, benzoyl peroxide, lauroyl peroxide, peracetic acid, persuccinic acid, di-tert-butyl peroxide, tert-butyl hydroperoxide, cumene hydroperoxide, etc. Organic peroxides can be used together with hydrogen peroxide within a range that does not impair the effects of the present invention.

〔Effect of the invention〕

The fumaric acid copolymer obtained by the method of the present invention configured as described above has a number average molecular weight of 3°O to 5000,
It is preferably 400 to 4000, and the D value (MW/M N') representing molecular weight distribution [MW is weight average molecular weight, MN is number average molecular weight] is 2.5 or less, preferably 2.0 or less It has the following characteristics.

The method of the present invention provides a method for economically producing a fumaric acid copolymer having the above-mentioned characteristics at a high yield in an aqueous medium, and includes the above-mentioned water treatment agent, detergent additive, and Refining aid for cellulose fiber, bleaching aid for cellulose fiber, dyeing aid for cellulose fiber, bulb bleach pre-treatment agent, bentonite slurry conditioner, deodorization in combination with polyvalent metals such as iron, copper, manganese, zinc, etc. It can be very suitably used in a wide range of applications such as inorganic pigment dispersants, deinking aids for waste paper recycling, and chelating agents.

〔Example〕

EXAMPLES Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to these Examples. Note that % and parts in the examples indicate weight % and parts by weight, respectively.

Example 1 1160 parts of fumaric acid and 1000 parts of ion-exchanged water were placed in a 5Q four-bottle flask equipped with a thermometer, stirrer, and reflux condenser.
part, iron(II) sulfate ammonium hexahydrate 0.163
(10 ppm as "Fe"; based on the total weight of monomer components charged), the temperature of the dispersion was raised to boiling temperature under normal pressure while stirring. Next, 80% acrylic acid was added to the dispersion while stirring. 1,450 parts of the aqueous solution and 867 parts (20 g; per mole of monomer component charged) of the aqueous solution and 60% hydrogen peroxide solution were continuously added dropwise over a period of 3 hours from separate dropping nozzles to effect copolymerization. After the dropwise addition was completed, stirring was continued for 1 hour at the boiling temperature of the system to complete the copolymerization reaction and obtain a homogeneous fumaric acid copolymer (1) with a solid content of 51.8%. (measured at 80'C) was O~0.5.

The molecular weight and molecular weight distribution of the obtained fumaric acid copolymer (1) were measured using gel permeation chromatography. The results were as shown in Table 1.

The column is Tosoh G-3000PW (XL)+
G-2500PW (XL) was used, and a phosphate buffer (pH 7) was used as the eluent. Polyethylene glycol (manufactured by General Sciences) was used as a molecular weight standard sample.

Examples 2 to 8 The types and amounts of metal ions used in Example 1, the amounts of hydrogen peroxide used, and the amounts of the 80% acrylic acid aqueous solution to be dropped were as shown in Table 1. Fumaric acid copolymers (2) to (8) were obtained in the same manner as in Example 1. The obtained fumaric acid copolymers (2) to (8) were
The results are shown in Table 1.

Example 9 A fumaric acid copolymer (9) was obtained in exactly the same manner as in Example 1, except that 100 parts of a 48% aqueous sodium hydroxide solution was added during the preparation.

The obtained fumaric acid copolymer (9) was analyzed in the same manner as in Example 1, and the results are shown in Table 1.

Examples '10 to 16 Same as Example 1 except that the type of water-soluble unsaturated monomer (b) used and the type and amount of metal ion species used were as shown in Table 1. Fumaric acid copolymers (1O) to (16) were obtained in exactly the same manner.

The obtained fumaric acid copolymers (IO) to (16) were analyzed in the same manner as in Example 1, and the results are shown in Table 1.

Example 17 A fumaric acid copolymer (17) was obtained in exactly the same manner as in Example 1, except that 200 parts of a 48% aqueous sodium hydroxide solution was added at the time of preparation.

The obtained fumaric acid copolymer (17) was analyzed in the same manner as in Example 1, and the results are shown in Table 1.

Example 18 A fumaric acid copolymer (18) was obtained in exactly the same manner as in Example 1, except that 50 parts of isopropanol was added during the preparation. The obtained fumaric acid copolymer (1
8) was analyzed in the same manner as in Example 1, and the results are shown in Table 1.

Comparative Example 1 A comparative fumaric acid copolymer (1) was obtained in exactly the same manner as in Example 1, except that iron (n) ammonium sulfate hexahydrate was not used at all. The comparative fumaric acid copolymer (1) obtained was analyzed in the same manner as in Example 1, and the results are shown in Table 2.

Comparative Examples 2 to 4 The type and amount of metal ions used in Example 1 were
Comparative fumaric acid copolymers (2) to (4) were obtained in exactly the same manner as in Example 1 except as shown in the table. The comparative fumaric acid copolymers (2) to (4) obtained were analyzed in the same manner as in Example 1, and the results are shown in Table 2.

Comparative Example 5.6 In Example 1, 1214 parts of a 48% sodium hydroxide aqueous solution was added at the time of preparation, and the type and amount of metal ions were changed as follows.
Comparative fumaric acid copolymer (5) was prepared in the same manner as in Example 1 except as shown in the table.

(6) was obtained. The obtained comparison fumaric acid copolymer (5).

(6) was analyzed in the same manner as in Example 1, and the results are shown in Table 2.

Comparative Example 7.8 Comparative fumaric acid copolymers (7) and (8) were prepared in the same manner as in Example 1, except that the amount of acrylic acid used in Example 1 was as shown in Table 2. The comparative fumaric acid copolymers (7) and (8) obtained were analyzed in the same manner as in Example 1, and the results are shown in Table 2.

Examples 19 to 36 Fumaric acid copolymers (1) to (1) obtained in Examples 1 to 18
The following tests were conducted to evaluate the performance of No. 18) as a scale inhibitor. Pour 170 g of water into a glass bottle with a capacity of 225 ml, and add 1.56% calcium chloride dihydrate aqueous solution Log and fumaric acid copolymers (1) to (18).
3 g of a 0.02% aqueous solution (3 ppm based on the obtained supersaturated aqueous solution) was mixed, and a 3% aqueous sodium bicarbonate solution Log and 7 g of water were added to bring the total amount to 200 g. The obtained supersaturated aqueous solution containing 530 ppm of calcium carbonate was tightly stoppered and heat-treated at 70° C. for 3 hours. After cooling, the precipitate was then filtered through a 0.1μ membrane filter, and the filtrate was analyzed according to JIS KOIOI.

Calcium carbonate scale suppression rate (%) was determined by the following formula. The results obtained are shown in Table 3.

-B Scale inhibition rate (%) = A: Concentration of calcium dissolved in the liquid before the test B Concentration of calicilam in the filtrate without the addition of a scale inhibitor C Concentration of calcium in the filtrate after the test Comparative Examples 9 to 16 Implementation The comparative fumaric acid copolymers (1) to (8) obtained in Comparative Examples 1 to 8 were evaluated for their performance as scale inhibitors in exactly the same manner as Examples 18 to 34. The obtained results are shown in the fourth
Shown in the table.

-B No. 3 table No. table

Claims (1)

[Claims] 1. 30 to 70% by weight of fumaric acid (a) and 70 to 30% by weight of other water-soluble unsaturated monomers (b) (however, fumaric acid (a)
) and the water-soluble unsaturated monomer (b) are 100% by weight. ) When polymerizing the monomer component consisting of , a fumaric acid copolymer characterized in that in the presence of two or more metal ions, 3 to 100 g of hydrogen peroxide (to 1 mole of monomer component) is used as a polymerization catalyst, and the pH during polymerization is less than 2. Method of manufacturing coalescence. 2. The method for producing a fumaric acid copolymer according to claim 1, wherein the water-soluble unsaturated monomer (b) is (meth)acrylic acid (salt). 3. The method for producing a fumaric acid copolymer according to any one of claims 1 and 2, wherein the pH during polymerization is 1.5 or less. 4. The method for producing a fumaric acid copolymer according to any one of claims 1 to 3, wherein the aqueous medium is water.