JPH0743367B2 - Solvent polarity indicator - Google Patents

Description

TECHNICAL FIELD The present invention relates to a polarity indicator material for a solvent in which a hue is changed by a change in polarity of a pure solvent or a mixed solvent, and the hue difference can be visually judged.

[Conventional technology]

In general, the polarity of a solvent depends on the dipole moment of the solvent molecule and the polarizability of the molecule.
For the sake of convenience, numerical values such as the refractive index have been used. Furthermore, attempts have been made to quantify the polarity of the solvent by measuring the reaction rate of a specific reaction in the solvent [V. Gutmann & R. Sch.
midt; Coord.Chem.Rev. 12 , 263, (1974)]. However, it was difficult to quantify the polarity of the solvent, especially the polarity of the mixed solvent, and it was difficult to handle. Further, there is also a problem that the dipole moment and the dielectric constant do not always accurately represent the polarity when the interaction between the solvent and the solute is strong.

[Problems to be Solved by the Invention]

The present invention has been made to solve the above-mentioned problems, and a solvent that can easily confirm the polarity of the solvent by changing the color tone of the solution caused by the polarity of the solvent when the solute is dissolved in the solvent. It is to provide a polarity indicating material.

[Means for Solving the Problems]

The solvent polarity indicator material of the present invention is characterized by comprising a polymer represented by the following general formula (I).

[In the formula, R ₁ represents an alkyl group having 3 or more carbon atoms or an alkylcarbonyl group in which the alkyl moiety has 3 or more carbon atoms, and R _{2 to} R ₅ are each a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or aryl. Represents a group, and n and m are m / (n + m) = 0 to ₁ (however, when R ₁ is the alkylcarbonyl group, m / (n + m) = 0.1 to 0.8), and n + m = 10 to 400 Is a number that satisfies. The polymer represented by the above general formula (I) used in the present invention is (1) after oxidative polymerization of aniline or an aniline derivative represented by the following general formula (II), or after reducing the obtained aniline polymer. , And the formula: R ₁ X (R ₁ has 3 carbon atoms
The above alkyl group or an alkylcarbonyl group whose alkyl moiety has 3 or more carbon atoms, X represents Cl, Br or I), and (2)
The aniline or aniline derivative represented by the general formula (II) and the N-substituted aniline or aniline derivative represented by the following general formula (III) can be synthesized by oxidative polymerization.

(In the formula, R ₁ ′ represents an alkyl group having 3 or more carbon atoms, and R _2-5
Have the same meanings as described above. ) Examples of the aniline derivative represented by the general formula (II) used for synthesizing the polymer of the present invention include m-anilidine, o-anilidine, m-toluidine, o-toluidine, 2,3-diethoxyaniline, 2, 5-diphenylaniline, 2-phenyl-3-ethylaniline, 2-chloro-3-methylaniline, 2-bromo-3-methylaniline, 2-chloro-3-ethylaniline, 2-bromo-3-ethylaniline, 2-chloro-3-n-propylaniline, 2-chloro-3-n-butylaniline, 2-bromo-3-n-butylaniline, 2-n-propylaniline, 3-n-propylaniline, 2-n -Butylaniline, 3-n-butylaniline, 2-i-propylaniline, 3-i-propylaniline, 2-i-butylaniline, 3-i-butylaniline, 2- -Butylaniline, 3-t-butylaniline, 2-stearylaniline, 3-stearylaniline, 2-docosylaniline, 3-docosylaniline, 2,3,5-triethylaniline, 2,3,5-tri ( n-propyl) aniline, 2,3,5,6-tetramethylaniline,
2,3,5,6-tetraethylaniline and the like can be mentioned.

The N-substituted aniline or aniline derivative represented by the general formula (III) includes Nn-propynylaniline, Nn-butylaniline, Nn-pentylaniline, Nn-octylaniline and N-n-octylaniline. -N-decylaniline, Nn-dodecylaniline, Nn-hexadecylaniline, N-dodecylaniline, N-stearylaniline, Nn-propyl-2-methoxyaniline, N
-N-butyl-m-toluidine, Nn-butyl-o-
Examples include toluidine, N-benzylaniline, diphenylamine and the like.

Further, the alkyl group having 3 or more carbon atoms in R ₁ of R ₁ X and the alkyl moiety of the alkylcarbonyl group are n-propyl, n-butyl, i-butyl, seo-butyl, t-butyl, n-pentyl. , N-hexyl, n-butyl, n-octyl, n-nonyl, n-decyl, n-
Dodecyl, n-hexadecyl, docosyl, stearyl and the like can be mentioned.

The oxidative polymerization of aniline or an aniline derivative or the oxidative polymerization of aniline or an N-substituted derivative of aniline with an aniline or an aniline derivative or N-substitution of the aniline derivative or aniline derivative is carried out in the synthetic methods of the above (1) and (2). A method of electrolytically oxidizing the body under constant potential, constant current, or constant voltage conditions in acidic aqueous solution or organic solvent, or persulfate, periodate, dichromate, hydrogen peroxide, iron chloride, etc. Although it can be carried out by a method using an oxidizing agent, the latter oxidative polymerization method is cheaper and easier.

Since the polymer of the present invention obtained as described above contains a considerable amount of a dopant such as an acid present in the reaction system, it has poor solubility in a solvent. Therefore, in order to improve the solubility, it is necessary to dope with a large amount of aqueous ammonia. In the case of the synthesis method of (1), the polymer obtained by oxidative polymerization is reduced with a reducing agent such as hydrazine to obtain the above formula: R ₁ X or R ₁ COX and N-methyl-2-pyrrolidone. The resulting polymer is dedoped and used.

〔Example〕

 The present invention will be described in detail below with reference to examples.

Example 1. 5 g of aniline was dissolved in 100 ml of a 1 mol / sulfuric acid aqueous solution, and 100 ml of a sulfuric acid aqueous solution in which 3 g of ammonium persulfate was dissolved was added at 0 ° C. with stirring. After reacting for 4 hours, the precipitated solid is filtered off, washed thoroughly with water, dispersed in 100 ml of water, and 100 ml of aqueous ammonia is added and stirred for 4 hours. The solid matter was filtered off, washed thoroughly with water, dispersed in 100 ml of water, 25 g of hydrazine was added, and the mixture was stirred for 8 hours. Since the dispersed solid matter became white, this was filtered off in nitrogen and dried to obtain 4 g of a polymer. This polymer under a nitrogen stream,
It was dissolved in 200 ml of N-methyl-2-pyrrolidone, 11 g of lauryl bromide was added dropwise, and stirring was continued for 4 hours. The reaction mixture was poured into 1 of water, the precipitate was filtered off, washed thoroughly with water, then dedoped with aqueous ammonia and dried under reduced pressure to obtain a polymer represented by the general formula (I). . The molecular weight of this polymer was measured by GPC to find that it had a number average molecular weight of 34,000 in terms of polystyrene (using a column for NMP, Shodex K
D-80M, m + n = about 130). Further, it was determined from the elemental analysis value that m / (m + n) = 1.0.

Example 2. 5 g of aniline was dissolved in 100 ml of a 1 mol / sulfuric acid aqueous solution, and 100 ml of a sulfuric acid aqueous solution containing 3 g of ammonium persulfate was dissolved at 0 ° C.
Was added with stirring. After reacting for 4 hours, the precipitated solid matter was separated by filtration, washed thoroughly with water, dispersed in 100 ml of water, 100 ml of ammonia water was added, and the mixture was stirred for 4 hours. The solid was filtered off, washed thoroughly with water, dispersed in 100 ml of water, 25 g of hydrazine was added, and the mixture was stirred for 8 hours.
Since the dispersed solid matter became white, this was filtered off in nitrogen and dried to obtain 4 g of a polymer. This polymer was dissolved in 200 ml of N-methyl-2-pyrrolidone under a nitrogen stream,
Octanoyl chloride (g) was added dropwise, and stirring was continued for 4 hours. The reaction mixture is poured into water 1 and the precipitate is filtered off,
The polymer was thoroughly washed with water, then dedoped with aqueous ammonia, and dried under reduced pressure to obtain a polymer represented by the general formula (I). When the molecular weight of this polymer was measured by GPC,
The number average molecular weight was 15,000 in terms of polystyrene (using a column for NMP, Shodex KD-80M, m + n = about 100). Further, it was determined from the elemental analysis value that m / (m + n) = 0.45.

Example 3. The same treatment as in Example 1 was carried out except that 5 g of 2-methoxyaniline was used in place of aniline in Example 1.
3.5 g of the polymer represented by the general formula (I) was obtained. When the molecular weight of this polymer was measured by GPC, the number average molecular weight in terms of polystyrene was 15000 (using a column for NMP, Shodex KD-8
0M, m + n = about 50). Also, from the elemental analysis values,
It was determined that m / (m + n) = 1.0.

Example 4. In Example 1, m-toluidine was used instead of aniline.
The same treatment as in Example 1 was carried out except that 5 g was used, and 3.5 g
A polymer represented by the general formula (I) was obtained. When the molecular weight of this polymer was measured by GPC, the number average molecular weight was 14000 in terms of polystyrene (using a column for NMP, Shodex KD-80M,
m + n = about 50). From the elemental analysis value, m /
It was determined to be (m + n) 1.0.

Example 5 The same process as in Example 1 was carried out except that 8 g of lauryl bromide was used in Example 1, to obtain 4 g of the polymer represented by the general formula (I). When the molecular weight of this polymer was measured by GPC, the number average molecular weight in terms of polystyrene was 26,000.
(Using NMP column, Shodex KD-80M, m + n = approx. 150)
Met. Also, from the elemental analysis value, m / (m + n) = 0.5
Was decided.

Example 6. The same treatment as in Example 1 was carried out except that 13 g of hexadecyl bromide was used in place of lauryl bromide in Example 1, to obtain 4 g of the polymer represented by the general formula (I). When the molecular weight of this polymer was measured by GPC,
The number average molecular weight was 34,000 in terms of polystyrene (using a column for NMP, Shodex KD-80M, m + n = about 150). In addition, m / (m + n) = 1.0 was determined from the elemental analysis values.

Example 7 The same treatment as in Example 2 was carried out except that 13 g of hexadecanoyl chloride was used in place of octanoyl chloride in Example 2, to obtain 5 g of the polymer represented by the general formula (I). When the molecular weight of this polymer was measured by GPC, the number average molecular weight in terms of polystyrene was 26,000 (using a column for NMP, Shodex KD-80M, m + n = about 150).
Moreover, m / (m + n) = 0.50 was determined from the elemental analysis value.

Example 8. N-n-butylaniline 0.1 mol /, perchloric acid 0.2 mol /
Using a platinum plate as a working electrode and a counter electrode in an aqueous solution containing the same, electrolytic polymerization was performed for 30 minutes at a constant potential of 0.8 V with respect to a saturated calomel electrode to form a green polymer as a working electrode. The working electrode was dedoped at a reverse potential of -0.3 V for 1 hour and then dried to obtain 0.05 g of the polymer represented by the general formula (I). When the molecular weight of this polymer was measured by GPC, the number average molecular weight was 5900 in terms of polystyrene (using a column for NMP, Shodex KD
-80M, m + n = about 40).

The polymers of the present invention obtained in Examples 1 to 8 have a structure in which R _{1 to} R ₅ in the general formula (I) are as shown in the following table.

When 0.1 mg of the polymer as described above was dissolved in 1 ml of each solvent shown in Table 1, the color tone of the solution was changed depending on the polarity of the solvent, and it was possible to visually judge the hue difference. .

The color tone at this time was deeper blue as the polarity of the solvent was larger, and purple or green as the polarity was smaller.

As described above, it was confirmed that the polymer of the present invention represented by the general formula (I) exhibits the results shown in Table 1 as a solvent polarity indicating material.

[Effect of the invention] The polymer of the present invention, when dissolved in a solvent, has different hues due to a change in polarity of a pure solvent or a mixed solvent,
It is a solvent polarity indicator material whose hue difference can be visually determined, and is useful for use as a simple indicator of a solvent.

Claims (1)

[Claims] 1. A solvent polarity indicator material comprising a polymer represented by the following general formula (I). [In the formula, R ₁ represents an alkyl group having 3 or more carbon atoms or an alkylcarbonyl group in which the alkyl moiety has 3 or more carbon atoms, and R _{2 to} R ₅ are each a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or aryl. And n and m are m / (n + m) = 0 to ₁ (provided that R ₁ is the alkylcarbonyl group, m / (n + m) = 0.1 to 0.8), and n + m = 10 to 400. Is a number that satisfies. ]