JPH11292965A - Polymer-solubilizing agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polymer solubilizing agent excellent in solubilizing ability and having biodegradability and high safety to organisms by including a specific modified polyaspartic acid (salt). SOLUTION: This polymer solubilizing agent comprises as modified polyaspartic acid (salt) having an alkyl group in the molecule, where a >=4C alkyl group is preferable and a >=6C alkyl group is more preferable as the alkyl group. An alkali metal salt is preferable as the salt. The alkyl group content of the modified polyaspartic acid (salt) is preferably 0.1-80 mol.% based on one aspartic acid unit and the weight average molecular weight is preferably 50-500,000. The modified polyaspartic acid (salt) is obtained by a method producing, e.g. polysuccinimide from aspartic acid, an the like, modifying the resultant polysuccinimide with an alkyl group-containing compound having reactivity with an imide ring and hydrolyzing the modified compound, or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a polymer solubilizer. More specifically, the present invention relates to a polymer solubilizer containing a modified polyaspartic acid having an alkyl group in a molecule and / or a salt thereof. The polymer solubilizer of the present invention has excellent solubilizing ability, and also has biodegradability or biosafety, and can be widely used in cosmetics, pharmaceuticals, food, feed, cutting oil, and the like.

[0002]

2. Description of the Related Art As a polymer solubilizing agent, a synthetic water-soluble surfactant such as polyoxyethylene alkyl ether and an alkyl-modified water-soluble polymer have been known. However, conventional solubilizers have little biodegradability or high biosafety, so if they are discarded as they are after use, they remain in the natural environment, imposing a burden on the environment, and being used on the human body. In such a case, there is a problem that biological safety may be impaired. On the other hand, polyamino acids are known as biodegradable functional polymers, and among them, polyaspartic acid and polyglutamic acid have attracted attention. In particular, polyaspartic acid is easily obtained by thermally polymerizing a reaction product of maleic acid and ammonia or aspartic acid and then hydrolyzing it, and thus various uses have been proposed.

[0003]

However, the performance of polyaspartic acid as a solubilizing agent has not been said to be sufficient as compared with those conventionally used. An object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a polymer solubilizer having excellent solubilizing ability and having biodegradability or high biosafety.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in view of such circumstances, and as a result, have found that polyaspartic acid and / or
Alternatively, it has been found that by introducing an alkyl group into the salt thereof, it is possible to greatly improve the solubilizing ability while maintaining high biodegradability, and have completed the present invention. That is, the gist of the present invention resides in a polymer solubilizing agent containing a modified polyaspartic acid having an alkyl group in a molecule and / or a salt thereof. Hereinafter, the present invention will be described in detail.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The polymer solubilizer of the present invention is a modified polyaspartic acid or a salt thereof having an alkyl group in its molecule, that is, an alkyl group bonded to the molecule. In this case, the alkyl group is not particularly limited, but preferably has 4 or more carbon atoms, and more preferably has 6 or more carbon atoms. Also, as the salt,
Usually, an alkali metal salt is used. The method for producing the modified polyaspartic acid and / or its salt is not particularly limited, but preferred examples of the production method include the following methods.

(1) Polysuccinimide is produced from aspartic acid and the like, and the polysuccinimide is hydrolyzed after being modified with an alkyl group-containing compound reactive with an imide ring. (2) An alkyl group-containing polysuccinimide is produced by subjecting aspartic acid or the like to a polycondensation reaction with a mixture of alkyl group-containing compounds, and the modified polysuccinimide is hydrolyzed. (3) After producing polyaspartic acid by a usual method, it is modified with an alkyl group-containing compound having a functional group reactive with a carboxyl group. Among them, (1) and (2) are more preferable.

Synthesis Method (1) (Polysuccinimide) The polysuccinimide is not particularly limited, and ones produced using various known monomers can be used, and copolymers can also be used.
In the case of a copolymer, it is preferable that the polymer contains 50 mol% or more of succinimide units. The molecular weight of the polysuccinimide is preferably equivalent to the molecular weight of the finally obtained alkyl group-containing polyaspartic acid or a salt thereof, and has a weight average molecular weight of 500 to 5,000.
00 is preferred.

[0008] Among the methods for producing polysuccinimide, the most preferred is to use aspartic acid as a monomer,
This is a method of performing polycondensation under heating in the presence of a catalyst. This polysuccinimide is described, for example, in JP-B-48-2063.
8, US Pat. No. 5,057,597, US Pat. No. 5,142,062, US Pat.
219,986, JP-A-6-248075, JP-A-7-126379, JP-A-7-216
No. 084, JP-A-8-176297, and the like. The outline of the monomer and the catalyst is as follows.

Examples of the monomer include a reaction product of maleic acid and ammonia, maleamic acid and / or aspartic acid. Preferred is aspartic acid. Aspartic acid may be in D-form, L-form or a mixture thereof. good. When a solvent is used at the time of the polymerization reaction, one having a relatively high molecular weight can be produced, but polymerization can be carried out without a catalyst. The presence or absence of a catalyst is not particularly limited, but the use of a catalyst is preferable because the polymerization rate and the degree of polymerization are increased.

The catalyst is preferably an acid catalyst. Specific examples thereof include inorganic acids such as sulfuric acid, sulfuric anhydride, phosphoric acid, polyphosphoric acid, metaphosphoric acid, condensed phosphoric acid, phosphoric anhydride, and p-toluenesulfone. Organic acids such as acid, trichloroacetic acid, trifluoroacetic acid, trifluoromethanesulfonic acid and the like can be mentioned. Other examples include phosphoric acid monoester, phosphoric acid diester, phosphoric acid triester, phosphite monoester, phosphite diester, phosphite triester and the like, among which phosphoric acid, polyphosphoric acid, metaphosphoric acid Preferred are condensed phosphoric acid, phosphoric anhydride, phosphoric acid monoester, phosphoric acid diester, phosphoric acid triester, phosphite monoester, phosphite diester, and phosphite triester.

These acid catalysts are used in an amount of usually 0.1 to 30 parts by weight, preferably 0.5 to 25 parts by weight, based on 100 parts by weight of the polymer raw material. When the amount is less than 0.1 part by weight, the effect of improving the speed in the polycondensation reaction is small. On the other hand, if the amount exceeds 30 parts by weight, the reaction product is in a solidified state at the time of polymerization, and a large burden is imposed on the stirring, which is not preferable.

(Alkyl group-containing compound) As the alkyl group-containing compound, any compound having a functional group reactive with an imide ring in polysuccinimide and an alkyl group can be used without particular limitation. As the functional group reactive with the imide ring, for example, a primary or secondary amino group, specific examples of the alkyl group-containing compound include a primary or secondary amino group and other And compounds having one or more alkyl groups.

The alkyl group is not particularly limited, but preferably has 4 or more carbon atoms.
C6 or more is more preferable. Specific examples of such compounds include, for example, butylamine, pentylamine,
Amine compounds in which an alkyl group such as hexylamine, octylamine, decylamine, dodecylamine, tetradecylamine, hexadecylamine, octadecylamine is substituted by one nitrogen atom, dibutylamine, dipentylamine, dihexylamine, dioctylamine, didecylamine, didecylamine Examples include amine compounds in which two alkyl groups such as dodecylamine are substituted with two nitrogen atoms. Of these, dodecylamine and hexadecylamine are preferred.

(Introduction amount of alkyl group) The introduction amount of the alkyl group-containing compound into the polysuccinimide is preferably 0.1 to 80 mol%, more preferably 0.2 to 60 mol%, based on the imide unit. . When the amount of the alkyl group introduced is less than 0.1 mol% or more than 80 mol%, the solubilizing ability is reduced. (Reaction method) The reaction between polysuccinimide and an alkyl group-containing compound is not particularly limited, and can be performed in the presence or absence of a solvent. The reaction temperature is preferably from 0 ° C to less than 350 ° C, more preferably 5 ° C.
It is in the range of not less than 300 ° C. If the temperature is lower than 0 ° C., the reaction does not easily proceed, and if the temperature is 350 ° C. or higher, the performance as a solubilizer is low. The reaction time is preferably 1 second to 30 days, more preferably 10 seconds to 20 days.

When a solvent is used, a solvent that dissolves polysuccinimide is preferred. Specifically, N, N-dimethylformamide, dimethylsulfoxide, N, N-
Examples include aprotic polar solvents such as dimethylacetamide, N-methylpyrrolidone, and sulfolane. The amount of the solvent used is preferably based on 100 parts by weight of the polymer.
10 to 10000 parts by weight, more preferably 20 to 500 parts by weight
0 parts by weight.

When no solvent is used, the reaction can be carried out in the presence of an acidic compound such as phosphoric acid, sulfonic acid, or haloacetic acid in the amount of 1 to 2 times the amount of the alkyl group-containing compound in terms of reaction rate and reaction rate. It is preferable from the viewpoint of uniformity. The reaction can be performed in a batch system or a continuous system. The product can be isolated by a conventional method, and examples thereof include a method of distilling off the solvent and a method of crystallizing with a poor solvent for the polymer.

Synthesis method (2) (Polycondensation after mixing an alkyl group-containing compound and aspartic acid) After mixing a monomer such as aspartic acid and an alkyl group-containing compound, polycondensation is carried out, and the polysuccinimide into which the alkyl group is introduced. Can be carried out in the same manner as in the synthesis of polysuccinimide using the above-mentioned raw materials. In this case, the amount of the alkyl group-containing compound used is preferably from 0.001 to aspartic acid.
0.8 mole times, more preferably 0.005 to 0.6 mole times. As the polymerization catalyst, it is particularly preferable to use phosphoric acid, phosphorous acid, or phosphite triester.

(Hydrolysis) The above synthesis method (1) or (2)
Is hydrolyzed to obtain an alkyl group-containing polyaspartic acid, which can be carried out according to a conventional method. As a typical example, J.I. Am. Chem.
Soc. , 80, 3361 (1958); Org.
Chem. , 26, 1084 (1961), U.S. Pat. No. 5,221,733, U.S. Pat.
It may be performed according to the specification of Japanese Patent No. 783, JP-A-60-203636 and the like. In a preferred embodiment, 50 to 1000 parts by weight of water is added to 100 parts by weight of the reaction product, and an alkali metal hydroxide is added in an amount of 1 to 3 moles per mole of the imide ring, The reaction is performed at 0 to 50 ° C for 10 minutes to 8 hours. As a result, most of the imide ring is opened. As the alkali metal hydroxide, sodium hydroxide and potassium hydroxide are usually used.

The hydrolysis product thus obtained is an alkali metal salt of an alkyl group-containing polyaspartic acid, and the alkyl group-containing polyaspartic acid according to the present invention includes the same. When an acid acts on this alkali metal salt type polyaspartic acid, free polyaspartic acid can be obtained. By adjusting the amount of the acid used, the ratio between the free form and the salt form of the carboxylic acid group of polyaspartic acid can be arbitrarily adjusted. The molecular weight of the polyaspartic acid is not particularly limited, but is preferably from 500 to 500,000, more preferably from 1,000 to 200,000 in terms of weight average molecular weight in order to exhibit high solubilizing ability.

(Solubilizer) The amount of the alkyl group-containing modified polyaspartic acid and / or salt thereof to be added to the solubilizer of the present invention is not particularly limited, but is usually 0.1 to 60% by weight.
And preferably 1 to 50% by weight. The solubilizing agent of the present invention functions as an emulsifier when applied to a liquid and a substance having poor solubility in the liquid. Therefore, the solubilizer of the present invention can also be used as an emulsifier. (Biodegradability) The biodegradability of the present invention refers to a value measured by a measuring method based on the biodegradability test method (modified MITI method) of a new chemical substance indicated in the Chemical Substances Control Law. The decomposition rate refers to a value obtained as a percentage based on the measurement of total organic carbon (TOC), and a substance showing a decomposition rate of 40% or more in this evaluation can be regarded as a highly biodegradable substance.

[0021]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples. However, the present invention is not limited to these Examples unless it exceeds the gist thereof. The molecular weight of the modified polysuccinimide, the introduction ratio of the alkyl group-containing compound, the test for solubilizing methyl cinnamate, the test method for the biodegradability of the polymer, and the like are as follows. 1) Weight average molecular weight of alkyl group-containing modified polysuccinimide; polystyrene equivalent value obtained by gel permeation chromatography using a differential refractometer Column; PLgel 5 μm MIXE-C columns (manufactured by Polymer Laboratories) Free liquid; Dimethylformamide to which 20 mM lithium bromide has been added 2) Introduction rate of alkyl group-containing compound; alkyl group content in alkyl group-modified polyaspartic acid is ¹ H-N
It was determined from the measurement of MR.

3) Solubilization test of methyl cinnamate 2 g of methyl cinnamate was added to a polymer solution containing 0.02 g of polymer, 0.2 g of ethanol and 19.78 g of ion-exchanged water, stirred for 2 hours, and dissolved. Unfiltered methyl cinnamate was filtered and the absorbance of the filtrate was measured at 276.2 nm to quantify the amount of solubilized methyl cinnamate.
As a blank, a 1% by weight aqueous ethanol solution excluding the polymer was used.

4) Test Method for Biodegradability The biodegradability test was carried out in accordance with the test method for biodegradability of new chemical substances (modified MITI method) specified in the Chemical Substances Control Law. As the microorganism (activated sludge) used in this test, standard sludge purchased from the Chemical Inspection Association was used. The test conditions are specifically activated sludge concentration; 30 mg / l, sample concentration;
1, test solution volume: 300 ml, test temperature: 25 ± 1 ° C., test period: 28 days, standard substance: aniline. The decomposition rate was determined as a percentage based on the measurement of total organic carbon (TOC). Specifically, the total organic carbon content of the organic matter in the sample in the culture solution at the start of the biodegradability test is measured. . The reduced total organic carbon amount was determined by measuring the total organic carbon remaining in the culture solution, the reduced total organic carbon amount was divided by the total organic carbon amount at the start of the test, and the decomposition rate was calculated as a percentage. A closed system oxygen consumption measuring device (Okura Electric's self-recording BOD meter) was used as a biodegradability test device, and a TOC meter (TOC-50 manufactured by Shimadzu Corporation) was used as a total organic carbon measuring device.
00) was used.

Production Example 1 Production of polysuccinimide L-aspartic acid (5.0 kg) under a nitrogen gas atmosphere
And 85% phosphoric acid (500 g) were mixed with a super mixer (manufactured by Kawata Corporation) for 5 minutes to disperse the catalyst. The polycondensation reaction was performed as follows using a KRC kneader (50φ × 661.5 L, L / D 13.2) manufactured by Kurimoto Steel Works, Ltd. The mixture of aspartic acid and phosphoric acid obtained above was supplied at a heating medium of 260 ° C., a screw rotation speed of 30 rpm, and a discharge rate of 1 kg / h (average residence time of 16 minutes), to perform polycondensation. Was performed to obtain a brown powder. The resulting product was washed with water to remove phosphoric acid as a catalyst. The product obtained below is referred to as resin A
And The weight average molecular weight of this polysuccinimide is
17000.

Production 2 Production of polysuccinimide 200 m equipped with a cooler, thermometer, stirrer and water separator
L in a four-necked flask, 25 g of aspartic acid, 85%
2.5 g of phosphoric acid, 56 g of mesitylene and 24 of sulfolane
g. Subsequently, under normal pressure and under reflux of mesitylene (1
(62 ° C.) for 4.5 hours to carry out the polycondensation reaction. The water produced during this time was distilled out of the system together with mesitylene. After completion of the reaction, the reaction mixture was separated by filtration, and the product was washed four times with 100 g of pure water and further washed with 100 g of methanol. The product was dried at 80 ° C. under reduced pressure for 24 hours to give a pale yellow powder 17.9.
g was obtained. Hereinafter, the obtained product is referred to as a resin B. The weight average molecular weight of this polysuccinimide was 69000.

Example 1 Production of an alkyl group-containing polyaspartate A 100 mL eggplant-shaped flask was charged with resin A (10.0 g) and N, N-dimethylformamide (90.0 g), and the resin A was dissolved. Then dodecylamine (1
0.05 g) was added to the reaction solution at room temperature, and the mixture was stirred at room temperature under a nitrogen stream for 48 hours. After completion of the reaction, the reaction mixture was dropped into 500 mL of ion-exchanged water for crystallization. After filtration, the solid was washed with ion-exchanged water (500 mL) and methanol (500 mL).
Drying under reduced pressure for a time gave 17.86 g of a white solid. The weight average molecular weight of this dodecylamine-modified polysuccinimide was 20,000.

Next, for hydrolysis, 97% sodium hydroxide (0.6 g) and ion-exchanged water (37.5 g) were charged into a 50 mL beaker to dissolve sodium hydroxide. After cooling the beaker with ice water, the brown solid (2.5 g) was added little by little, and then added at room temperature for 24 hours.
Stirring was performed for hours. After completion of the reaction, the reaction solution was dropped into methanol (300 mL) to crystallize the polymer. After filtering the mixture, the solid was washed twice with methanol (300 mL) and dried under reduced pressure at 50 ° C. for 24 hours to obtain a white solid 2.38.
g was obtained. Hereinafter, this product is referred to as resin C. The dodecylamine introduction ratio of this resin calculated by proton NMR (deuterated water) was 47.6%. Table 1 shows the results of measuring the solubilizing ability and the biodegradability of this alkyl group-containing polyaspartic acid.

Example 2 Production of an alkyl group-containing polyaspartate A resin B (5.0 g) and N, N-dimethylformamide (45 g) were charged into a 100 mL eggplant-shaped flask, and the resin B was dissolved. Then dodecylamine (1.0 g)
Was added to the reaction solution at room temperature, followed by stirring at room temperature for 24 hours under a nitrogen stream. After completion of the reaction, the reaction solution was deionized water (5
(200 mL) and crystallized by filtration. After filtration, the solid was deionized water (500 mL) and methanol (500 mL).
L), and dried under reduced pressure at 100 ° C for 24 hours to obtain 5.25 g of a white solid. The weight average molecular weight of this dodecylamine-modified polysuccinimide is 70,000
Met.

Next, for hydrolysis, 97% sodium hydroxide (1.0 g) and ion-exchanged water (37.5 g) were charged into a 50 mL beaker to dissolve the sodium hydroxide. After cooling the beaker with ice water, the white solid was added little by little, and then stirred at room temperature for 24 hours. After the completion of the reaction, the reaction solution was methanol (300 mL)
And the polymer was crystallized. After filtration of the mixture, the solid was washed twice with methanol (300 mL) and treated at 50 ° C. for 24 hours.
After drying under reduced pressure for 2 hours, 2.96 g of a white solid was obtained. Hereinafter, this product is referred to as resin D. Proton NMR of this resin
(Deuterated water), the dodecylamine introduction rate is
It was 8.9%. Table 1 shows the results of measuring the solubilizing ability and the biodegradability of this alkyl group-containing polyaspartic acid.

Example 3 In a nitrogen gas atmosphere, L-aspartic acid powder (1.0 k
g), 85% phosphoric acid (100 g) and dodecylamine (138.5 g) were mixed for 5 minutes using a “Supermixer” (manufactured by Kawata Corporation) to obtain a uniform mixture. This mixture is called “KRC Kneader” (manufactured by Kurimoto Iron Works, 50φ).
× 661.5 L) to carry out a polymerization reaction. The operating conditions of the kneader were a heating medium temperature of 260 ° C., a screw rotation speed of 30 rpm, and an average residence time of 20 minutes. The weight average molecular weight of this dodecylamine-modified polysuccinimide was 12,000.

A 50 cc beaker equipped with a stirrer was charged with ion-exchanged water (8.0 g) and 93% sodium hydroxide (0.92 g). Under ice-cooling, 2.0 g of the light brown product obtained above was added little by little to the mixture, and the mixture was hydrolyzed by stirring at room temperature for 1 hour. Methanol 1
The above-mentioned hydrolysis solution was dropped into 00 ml, and 2.5 g of a yellowish white amine-modified sodium polyaspartate precipitated was added.
I got Hereinafter, this product is referred to as a resin E. The dodecylamine introduction ratio of this resin calculated by proton NMR (deuterated water) was 7.7%. Table 1 shows the results of measuring the solubilizing ability and the biodegradability of this alkyl group-containing polyaspartic acid.

Example 4 L-aspartic acid powder (40.0 g), 85% phosphoric acid (4.0 g) and hexadecylamine (7.27 g) were charged into a mixer (Oster blender), and mixed at room temperature for 15 minutes.
Mix for a minute to obtain a homogeneous mixture. The mixture obtained above was charged into Labo Plastmill (manufactured by Toyo Seiki Seisaku-sho, Ltd.), and the mixture was stirred at a set temperature of 230 ° C. for 30 minutes to obtain a light brown powder. The weight average molecular weight of this hexadecylamine-modified polysuccinimide was 12,000.

In a 50 cc beaker equipped with a stirrer, 9
7% sodium hydroxide (19.1 g) and ion-exchanged water (149.6 g) were charged. The product obtained above (45.0 g) was added thereto little by little under ice-cooling, followed by hydrolysis at room temperature for 1 hour with stirring. The hydrolyzed solution was dropped into 100 ml of methanol, and the precipitated alkyl group-containing sodium polyaspartate 51.9 was precipitated.
g was obtained. Hereinafter, this product is referred to as a resin F. The dodecylamine introduction rate of this resin calculated by proton NMR (deuterated water) was 8.9%. Table 1 shows the results of measuring the solubilizing ability and the biodegradability of this alkyl group-containing polyaspartic acid.

Comparative Example 1 In a 50 cc beaker equipped with a stirrer, 10 g of water and 97 g of water were added.
% Sodium hydroxide (1.4 g) was charged to dissolve the sodium hydroxide. After cooling the beaker with ice water, the resin A (3.0 g) obtained above was added little by little, and then stirred at room temperature for 1 hour to hydrolyze. The above hydrolyzed liquid was dropped into 100 ml of methanol, and 2.6 g of precipitated yellow-white sodium polyaspartate was precipitated.
I got After the reaction, the reaction solution was crystallized by pouring into 100 ml of methanol to obtain 2.6 g of yellow-white sodium polyaspartate. Hereinafter, this polyaspartate is referred to as resin G. Table 1 shows the results of measuring the solubilizing ability and the biodegradability of the resin G. Comparative Example 2 PEMUL commercially available from BFGoodrich
The solubilizing ability and biodegradation rate were measured using EN TR-2. Table 1 shows the results.

[0035]

According to the present invention, a polymer solubilizer having excellent solubilizing ability and biodegradability or having high biosafety can be obtained.

[0036]

[Table 1]

Claims (5)

[Claims] 1. A polymer solubilizer comprising a modified polyaspartic acid having an alkyl group in a molecule and / or a salt thereof. 2. A modified polyaspartic acid having an alkyl group in a molecule and / or a salt thereof obtained by hydrolyzing a modified polysuccinimide having an alkyl group in a molecule. 2. The polymer solubilizing agent according to 1. 3. The polymer solubilizer according to claim 1, wherein the alkyl group has 4 or more carbon atoms. 4. The modified polyaspartic acid having an alkyl group in the molecule and / or a salt thereof having an alkyl group content of 0.1 to 80 mol% based on one unit of aspartic acid. 4. The polymer solubilizing agent according to any one of items 1 to 3. 5. A modified polyaspartic acid having an alkyl group in the molecule and / or a salt thereof having a weight average molecular weight of 50.
The polymer solubilizer according to any one of claims 1 to 4, wherein the amount is from 0 to 500,000.