JPS5827771A - Water-based thickener - Google Patents

Abstract

PURPOSE:To provide a thickener composed of a copolymer containing polyoxyalkylene glycol mono(meth)acrylate as a constituent unit, usable over a wide pH range, having excellent chemical and physical stability, free from toxicity, and suitable for the appications in various fields. CONSTITUTION:The objective water-based thickener contains a copolymer having a number-average molecular weight of <=100,000 and containing (A) 20-99 (wt)% one or more polyoxyalkylene glycol mono(meth)acrylate of formula (R is H or methyl; m is 2-4; n is 2-20) and (B) 1-80% one or more other ethylenic unsaturated monomers copolymerizable with the compound (A). The component (A) is preferably polyoxyethylene glycol mono(meth)acrylate, etc., and the component (B) is preferably styrene, butadiene, acrylonitrile, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides polyoxyalkylene glycol mono(meth)
This invention relates to an aqueous thickener made of a copolymer containing acrylate as a constituent unit.

Conventional aqueous thickeners include sodium alginate,
Anionic systems such as sodium polyacrylate, maleic acid copolymer salts, polyacrylamide partially hydrolyzed salts, and cationic systems such as water-soluble aniline resin hydrochloride, polyethyleneimine-vinylpyridine copolymer salts, and polythiourea acetate salts. , and nonionic thickeners such as water-soluble urea resins, polyethylene oxide, polyvinyl alcohol, and polyacrylamide are known. However, the stability of the thickened aqueous solutions using these conventional water-based thickeners is poor, and the viscosity changes over time, and changes in the pH range of the solution can result in the formation of water-insoluble substances and precipitates. It has various drawbacks, such as poor solubility in other hydrophilic solvents, which limits its use, and problems with toxicity.

The present invention has been completed as a result of intensive research on an aqueous thickener ζ that does not have the above-mentioned drawbacks, and has a number average molecular weight of 100,000 or less containing polyoxy7alkylene7glycol mono(meth)acrylate as a constituent unit. The object of the present invention is to provide an aqueous thickener that exhibits excellent thickening properties by including all the copolymers as components.

The present invention is an aqueous thickener containing a copolymer containing the following (A) and (B) as structural units and having a number average molecular weight of 100,000 or less.

(A) General formula (where R is a hydrogen atom or a methyl group, m is 2 to 4
n is an integer from 2 to 20. ) 1 of polyoxyalkylene glycol monoacrylate or polyoxyalkylene glycol monomethacrylate represented by
20 to 99% by weight of one species or two or more species.

(B): 1 to 80 of one or two or more other ethylenically unsaturated monomers copolymerizable with the compound of formula C0
Weight% Compounds of formula [1] include polyoxyethylene glycol mono(meth)acrylate, polyoxypropylene glycol mono(meth)acrylate, polyoxytetramethylene glycol mono(meth)acrylate, and polyoxyethyleneoxypropylene glycol mono(meth)acrylate. )
Acrylate, polyoxyethylene oxytetramethylene glycol mono(meth)acrylate, polyoxypropylene oxytetramethylene glycol mono(meth)
Examples include acrylate, polyoxyethylene oxypropylene oxytetramethylene glycol mono(meth)acrylate, and the like.

These compounds (formula 11) are described in Japanese Patent Publication No. 52-304.
According to the production methods described in No. 89 and No. 53-15493, ethylene oxide, propylene oxide, butylene oxide, and tetrahydrofuran are individually or coaddition polymerized to hydroxyalkyl mono(meth)acrylate.

[The number of moles of alkylene oxide added in the compound of formula 13 is selected between 2 and 20 moles. If it is less than 2 moles, the water solubility of the copolymer will be low, and if it exceeds 20 moles, a large amount of unreacted substances will remain during copolymerization.

The reason why the proportion of the metal compound of formula (1) in the copolymer is limited to 20 to 99% by weight is that if it is less than 20% by weight, the copolymer will not become water-soluble.

Other ethylenically unsaturated monomers other than the compound of formula (1) include, for example, styrene, α-methylstyrene, P-methyl-α-methylstyrene, butadiene, acrylonitrile, vinyl acetate, glycidyl (meth)acrylate, Examples include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)meth)acrylate, acrylamide, N-menalol acrylamide, (meth)acrylic acid and its salts.

The copolymerization reaction for obtaining the copolymer of the present invention is carried out using a polymerization initiator in an organic solvent at a reaction temperature of 4° to 18°C (7°C).
"C preferably 6o to 10 CJ 'C range 0
．． It is carried out for 5 to 30 hours, preferably 1 to 20 hours. In this case, it is also possible to use a small amount of a chain transfer agent if necessary.

Examples of the organic solvent include methanol, ethanol, n
-furopanol, isopronominol, n-butanol, 5ec-butanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether,
Examples include ethylene glycol monobutyl ether, dimethylformamide, dimethyl sulfoxide, acetonitrile, acetone, and methyl ethyl ketone. These organic solvents are based on 100 parts by weight of ethylenically unsaturated monomer,
10 to 2000 parts by weight, preferably 50 to 10
00 parts by weight are used.

Polymerization initiators include benzoyl peroxide, methyl ethyl ketone peroxide, cumene hydroperoxide,
Examples include di-tert-butyl peroxide, iso-bunaroyl peroxide, tert-butyl peroxyoctanoate, dicumyl peroxide, and azobinisobutyronitrile. These are ethylenically unsaturated monomers 1
It is used in an amount of 001 to 10 parts by weight, preferably 005 to 5 parts by weight per 00 parts by weight.

In addition, mercaptans that can be used as chain transfer agents include dodecyl mercaptan and octyl mercaptan, and disulfides include bis-(hydroxyethyl) disulfide, diphenyldinulfide,
Examples include bis-(2-ethylhexyl) disulfide. The amount of these chain transfer agents used is 0.5 to 50 parts by weight per 100 parts by weight of the ethylenically unsaturated monomer.

The copolymer of the present invention has a number average molecular weight of 100,000 or less, preferably 5.0 or less, as measured by gel permeation chromatography. If the number average molecular weight exceeds 100,000, the solubility in water becomes poor.

The copolymer of the present invention includes water, alcohols, glycols,
Very soluble in other organic solvents.

Even if it is difficult to dissolve in water, it can be made into an aqueous solution using a water-compatible solvent such as alcohols or glycols.

Examples of the alcohols, glycols, and other organic solvents mentioned above include lower alcohols such as methanol, ethanol, and propatool, glycols such as ethylene glycol, propylene glycol, diethylene glycol, and dipropylene glycol, ethylene glycol monomethyl ether, and ethylene glycol. Glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene gelicol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, dipropylene glycol monomethyl Ether, glycol ethers such as diethylene glycol monobutyl ether and dipropylene glycol monobutyl ether, polyoxyalkylene glycol derivatives such as polyoxyethylene glycol, polyoxypropylene glycol, and holoxyethylene oxypropylene glycol, dimethylformamide, dimethyl sulfoxide, acetonitrile, Organic solvents include acetone, methyl ethyl ketone, and tetrahydrofuran.

The copolymer of the present invention is used as an aqueous thickener by adding it directly or by dissolving it in the above-mentioned solvent to a desired aqueous system. Targeted aqueous systems include not only water alone, but also all systems in which other substances are dissolved, suspended, or emulsified in water. The field of application of the water-based thickener of the present invention is not limited, and examples include water-based lubricating oils, hydraulic oils, quenching oils, metal working oils, cosmetics,
It can be used as a thickener for latex, water-based paints, paper processing agents, adhesives, binders, antifog agents, and dispersants.

The aqueous thickener of the present invention exhibits excellent solubility and thickening properties in water over a wide range of pH from 2 to 12, and is chemically and physically stable in an aqueous solution.
There is no change in viscosity or formation of precipitates over time, and there is no toxicity.

The water-based thickener of the present invention maintains fluidity at room temperature, is stable against mechanical shear stress, and has excellent lubricating performance, so it is used as a thickener for water-based lubricating oils, and also as a water-glycol thickener. It exhibits excellent effects as a base (thickener) for flame-retardant hydraulic oils, water-soluble quenching oils, and water-soluble metalworking oils.

Further, the water-based thickener of the present invention dissolves quickly in water to alcohol-based solvents and does not change in quality due to temperature or the po value of the solution, so it is highly effective as a cosmetic. For example, when applied to the skin, it has a unique light feel, so it can be used as a base for lotions, and it can also be used as a base for hair cosmetics, as it has moderate moisturizing properties and viscosity, and has good strength on the hair. The effect is excellent.

Furthermore, the water-based thickener of the present invention is non-thixotropic and has the performance as a protective colloid, so it exhibits excellent viscosity retention and chemical mechanical stability as a thickener for latex and water-based paints. .

The copolymer used in the present invention → ← + Life ← Existing natural polymer compounds for brooms such as gum tragacanth, zukuchi, sodium alginate, methyl cellulose, carboxymethyl cellulose, and starch, as well as synthetic polymers such as polyacrylamide and polyacrylic. Excellent as a thickener, binder, layer agent, antifog agent, dispersant, water reducer, etc. in fields such as paper and pulp processing woodworking, ceramics, cement, and refractories where acid soda, polyvinyl alcohol, etc. are used. Shows a mental effect.

Next, examples of the present invention will be shown.

Example-1 In a 2-volume glass reaction vessel equipped with a stirrer, a reflux tube, and a thermometer, 800 f of isopronominol and 160 g of polyoxyethylene glycol monomethacrylate with a number average molecular weight of 425 were placed. , 40 parts of butyl acrylate, and 2 parts of azobisisobunalonitrile (AIBN) were charged, and after purging the space with nitrogen gas, the temperature was raised to 80°C with stirring, and a copolymerization reaction was carried out at this temperature for 6 hours. . After that, ArBH2F dissolved in methyl ethyl ketone 501 was added, and the mixture was further aged for 6 hours at the same temperature.

After the obtained polymer was cooled to room temperature, it was added to 10,000 g of ethyl ether, mixed and stirred, and the precipitate at the bottom was separated. This precipitate was heated at 40° C. for 2 hours under a reduced pressure of 30 mmHg to remove remaining ethyl ether to obtain purified copolymer-A178.27'.

Example 2 Ethylenically unsaturated monomer was converted into polyoxyethylene oxypropylene monomethacrylate (E
Copolymer-B166, O
I got J'.

Example-3 N-butanol 750F was placed in the same reaction vessel as in Example-1.
, polyoxyethylene glycol monoacrylate 100J' with a number average molecular weight of 350, polyoxypropylene glycol monomethacrylate 50 with a number average molecular weight of 250
1. α-Methylnuthylene 50P, lauryl meccrylate 50J”;, benzoyl peroxide (BPO
) 5F was charged, and after replacing the space with nitrogen gas, the temperature was raised to 80° C. with stirring, and the copolymerization reaction was carried out at this temperature for 8 hours. Thereafter, BP05F dissolved in methyl ethyl ketone 50F was added and aged at the same temperature for 8 hours.

The obtained copolymer was purified in the same manner as in Example 1 to obtain copolymer-CI6B, 5J'.

Example-4 Isopropanol 800 was placed in the same reaction vessel as Example-1.
! , polyoxyethylene oxytetramethylene glycol monomethacrylate (BO:
THF=70:3D weight%) 100! , butyl acrylate 50J', acrylonitrile 50! , dodecyl mercaptan 6p, and BPO5J' were charged, and after replacing the space with nitrogen gas, the temperature was raised to 80° C. with stirring, and a copolymerization reaction was carried out at this temperature for 15 hours.

The obtained copolymer was purified in the same manner as in Example-1 to obtain copolymer-D152.7p.

Test Example 1 Solubility, thickening property, and stability of aqueous solutions were measured for copolymers A to D obtained in Examples 1 to 4, and sodium polyacrylate and polyvinyl alcohol as comparative products. The results are shown in Table 1. In Table 1, the sodium polyacrylate used was obtained by saponifying polymethyl acrylate with a degree of polymerization of 340 with sodium hydroxide, and the polyvinyl alcohol used had a degree of polymerization of 750 and a saponification degree of 99%.

The thickening property indicates the thickening property when dissolved in water, but since copolymer B is insoluble in water, it was measured by dissolving it in 50% ethanol water. The viscosity change due to temperature value is 5% aqueous solution (30℃)
The viscosity at pH 7 was set to 100, and the viscosity when adjusted to pH 3 or 11 by adding hydrochloric acid or sodium hydroxide was shown as an index.

In addition, the oral change in viscosity was determined by setting the viscosity immediately after dissolution of a 5% aqueous solution (30° C.) as 100, and the viscosity after each oral administration was expressed as an index.

As is clear from the results in Table 1, the aqueous 7 thickener of the present invention has excellent solubility, thickening ability, and aqueous solution stability.

Test Example-2 Example-1 as base (thickener) for water-based lubricating oil composition
A lubrication performance test was conducted using the copolymers A to D obtained in Examples 1 to 4 and an existing polyoxyalkylene glycol compound as a comparative example.

The composition other than the base is as follows.

Ion exchange water 4 filters 68 parts by weight Solvent (ethylene glycol) 46. i Additive Oleic acid 6.9 Morpholine
1.2 Potassium hydroxide 1,7 Penzotriazole 0.24 Silicon
006 Thickening effect and lubricity using a four-ball tester and a Chimken oil tester when the composition other than the base is constant (100 parts by weight) and the base is blended as shown in Table 2. was measured. The results are shown in Table 2. In Table 2, polyoxyethylene oxypropylene glycol has an oxyethylene:oxypropylene (weight ratio) of 75:25. The average molecular weight is 11,000, and polyoxyethylene glycol has an average molecular weight of 20,000.

From the results in Table 2, the product of the present invention is superior to existing polyoxyalkylene glycol compounds, which are comparative products, in terms of thickening properties and viscosity properties, and also has excellent lubricity due to its low-temperature fluidity. It can be seen that the oil can be used as a base or additive for water- to glycol-based flame-retardant hydraulic oils, metal plastic working oils, cutting or grinding oils, and water-based quenching oils.

Test Example 3 The product of the present invention was tested as a base (thickener) for cosmetics. An example of a formulation as a transparent liquid hair styling agent is shown below. Note that the number in parentheses appended to polyoxyalkylene indicates the number of moles added.

a) Copolymer-8 6.0 parts by weight b) Copolymer-06,OC C) Polyoxypropylene (!10) 2.0 Oxyethylene (25) Stearyl Ether d) Polyoxypropylene (!10) 0 .5
Oxyethylene (4) Nutearyl ether e) Ion exchange water 65.5f) Ethanol 20.0g) Fragrance, coloring agent, preservative
Appropriate amounts of ingredients a s b % Cs d and e were uniformly dissolved at 30 to 50° C., and then pre-mixed f and g were added and stirred until the solution became uniform and transparent. The resulting hair styling agent was a transparent liquid that provided adequate moisturizing properties to the hair and had strong hair styling ability.

Test Example 4 The product of the present invention was tested as a thickener for acrylic latex paint. The formulation and results are shown in Table 3.

Ta. In Table 3, the polymeric dispersant used was isobutylene and hydroxylated maleic anhydride copolymer (IJum salt), the viscosity Ku was the value measured using a Nutomer viscometer (25°C), and the adhesion was 1. The results of a peeling test using cellophane tape at intervals are shown; the denominator indicates the number of stripes, and the numerator indicates the number of stripes that did not peel off.

From the results shown in Table 3, it can be seen that the product of the present invention is superior to the comparative sodium polyacrylate-based thickener in terms of changes in viscosity over time and physical properties of the coating film.

Agent: Patent attorney Sei Yanagi Hara

Claims (1)

[Claims] (1) Contains the following (A) and (B) as structural units,
and a water-based thickener containing a copolymer with a number average molecular weight of 100,000 or less (where R is a hydrogen atom or a methyl group, m is 2 to 4
n is an integer from 2 to 20. ) in an amount of 20 to 99% by weight of one or more polyoxyalkylene glycol monoacrylates or polyoxyalkylene glycol monomethacrylates. (B): (1 to 80% of one or more other ethylenically unsaturated monomers copolymerizable with the compound of formula D)
weight%. (2) The compound of formula (1) is polyoxyethylene glycol mono(meth)acrylate, polyoxypropylene glycol mono(meth)acrylate, polyoxytetramethylene glycol mono(meth)acrylate, polyoxyethyleneoxypropylene glycol mono(meth)acrylate, ) acrylate, polyoxyethylene oxytetramethylene glycol mono(meth)acrylate, polyoxypropylene oxytetramethylene glycol mono(meth)acrylate and polyoxyethylene oxyfuran
The aqueous thickener (3) according to claim 1, which is a compound selected from v.pyreneoxytetramethylene glycol mono(meth)acrylate. -Methyl-α-methylstyrene, butadiene, acrylonitrile, vinyl acetate, glycidyl (meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (
meth)acrylate, lauryl(meth)acrylate,
2-Hydroxy gamma meth)acryle 4 sol, 2-hydroquine (meth)acrylate 1/-, cyclohexyl (meth)acrylate, acrylamide, N-
The aqueous thickener (4) according to claim 1 or 2, which is a compound selected from methylol acrylamide, (meth)acrylic acid, and salts thereof. Oils, metal processing oils, cosmetics, latex, water-based paints, paper processing agents,
The aqueous thickener according to any one of claims 1 to 3, which is a thickener for adhesives, binders, antifogging agents, or dispersants.