JPS6313932B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a novel method that can be used as a catalyst for various chemical reactions, immobilized artificial oxygen, microcapsules for chemicals, especially agricultural chemicals, insecticides, herbicides, etc., and fillers for gel chromatography. This invention relates to a crystalline composite of montmorillonite and cyclodextrin compounds and a method for producing the same.

Conventionally, cyclodextrin-based compounds have been used as microencapsulating agents to stabilize chemically unstable substances, especially pharmaceuticals, pesticides, herbicides, etc., by utilizing their molecular inclusion ability and catalytic ability. It is used as a solubilizer for poorly soluble substances and as a packing material for column chromatography. It has also attracted attention as an enzyme model, and attempts are being made to improve its functionality by introducing special functional groups and use it as an artificial enzyme.

In order to improve the functionality of cyclodextrin, conventional methods have been to introduce functional groups into cyclodextrin or to make it into a polymer.

An object of the present invention is to provide a complex in which cyclodextrin is complexed with an inorganic substance to have improved functionality, and a method for producing the same.

As a result of intensive research to achieve the above object, the inventors of the present invention found that by creating a composite by interposing montmorillonite, which is an inorganic material with a layered structure, and a cyclodextrin compound between the layers, the synergistic effect of the two creates a complex that cannot be obtained alone. The present invention was completed based on this knowledge.

The gist of the present invention is the general formula (X, Y) _2~3 Z ₄ O ₁₀ (OH) ₂・mH ₂ O(W) _n (where X is A, Fe(), Mn() and
Trivalent metal selected from Cr (), Y is Mg, Fe
(), Mn () and divalent metal selected from Ni,
Z is Si or A, W is Cu (), K, Na and Ca
montmorillonite, which has a layered structure represented by a metal selected from (m represents the number of water molecules);
It is a crystalline complex consisting of a cyclodextrin compound between its layers.

The cyclodextrin compound and montmorillonite used in the present invention are both compounds having molecular inclusion ability. Molecular inclusion ability means that there is a cavity of an appropriate size inside a three-dimensional or two-dimensional structure formed by bonding atoms or molecules, and other molecules can be incorporated into the cavity to form a specific crystal structure. It has the ability to

For example, cyclodextrin, which is a cyclic polymer of D-glucose, has a cylindrical cavity in the center with a diameter of 5 to 8 Å and a depth of 8 Å, and has a catalytically active alcohol group in the side chain, and has inclusion ability and catalytic activity. He has the ability.

Moreover, the montmorillonite represented by the above general formula has a layered structure and has inclusion ability. By introducing a cyclodextrin-based compound between the layers of this montmorillonite to form a complex, it becomes a complex with two clathrate lattices, one layered and one cylindrical. It has improved properties as a material, and has also been made useful as a microencapsulating agent for chemicals, especially pesticides, insecticides, and herbicides, as a filler for gel chromatography, and as an enzyme model. .

In the present invention, the cyclodextrin compounds to be combined with montmorillonite include α, β, γ,
Examples include δ-cyclodextrin alone, and derivatives thereof into which polar groups or cations such as alcohol groups, amino groups, and tetraalkylammonium groups are introduced.

The composite of the present invention can be produced by mixing an aqueous solution of a cyclodextrin compound with montmorillonite powder and holding the mixture for a certain period of time.
For example, 0.1 to 1 g of montmorillonite powder
An aqueous solution containing 2 mmol of a cyclodextrin compound is mixed and maintained at 20 to 60°C for 2 hours or more. In this case, the concentration of the cyclodextrin compound in the aqueous solution is not particularly limited, but within the range of solubility, it is preferably about 1 to 20 mM. Furthermore, when using a cyclodextrin derivative that is poorly soluble in water, an organic solvent is used alone or in combination. If the temperature is lower than 20°C, it will take a long time to form the complex, and if it exceeds 60°C, there is a risk of decomposition of the cyclodextrin compound, so a range of 20 to 60°C is appropriate.

The resulting composite was separated from the liquid and washed with water for 30 to 40 minutes.
Drying at ℃ for 12 to 24 hours yields a crystalline composite of montmorillonite-cyclodextrin compounds.

This composite has a microcomposite structure in which a cyclodextrin compound layer is incorporated between the silicate layers of montmorillonite, and the interlayer distance is 12 to
It increases from 15 Å (varies depending on the type of substituted ion and degree of dehydration) to the thickness of one molecular layer (thickness of 7 Å or more) or two molecular layers (thickness of 14 Å or more) of the cyclodextrin compound. In this case, whether one molecular layer or two molecular layers are included depends on the mixing ratio of both substances, but the maximum composite amount per gram of montmorillonite is 0.68 mmol for α-cyclodextrin-based compounds and 0.68 mmol for β-cyclodextrin. The amount is 0.60 mmol for γ-cyclodextrin type compounds, and 0.46 mmol for γ-cyclodextrin type compounds.

In the crystalline composite of the present invention, a cyclodextrin compound having a cylindrical wrapping lattice is present between layers of a layered structure of montmorillonite, thereby forming a crystalline composite.

Therefore, (1) the cyclodextrin-based compound alone is soluble, so it is difficult to separate the product, but the complex of the present invention is crystalline and the catalyst part is fixed and insolubilized, so the product can be separated. It is easy to carry out continuous reactions, and because it is combined with a layered lattice, it has high selectivity for reactions, making it excellent as a catalyst or artificial enzyme. (2) is a cyclodextrin compound alone,
Although the elution of the drug is relatively fast and the durability of the drug effect is poor, in the composite of the present invention, the drug is fixed in the synchrodextrin compound part between the montmorillonite layers, so the drug does not come into direct contact with, for example, moist areas in the soil. As a result, its elution is suppressed.
The medicinal efficacy is sustained over a long period of time, making it an excellent microcapsule. (3) Since the composite of the present invention has the separation effect of the montmorillonite layer, its separation ability is improved and it becomes an excellent chromatography filler. It can achieve excellent effects such as:

Example Cu () substituted product of montmorillonite Cu _0.26 (A _1.48 Fe _0.14 Mg _0.40 ) (Si _3.99 A _0.01 )
O ₁₀ (OH) ₂ ·mH ₂ O, 0.04 g and β-cyclodextrin derivative (mono(t-β-aminoethylamino-6-dioxy)-β-cyclodextrin) (hereinafter abbreviated as CDen) The mixture was mixed with 4 ml of a 12.7 mM aqueous solution of and shaken at 25°C for 10 days. After centrifuging the solid phase, it was washed with water and dried at 40°C.
A light purple powdery complex was obtained.

The contents of CDen, Cu() and water in this powder crystal are 0.58 mmo/g of each inorganic phase, respectively.
At 0.55 mmo and 6.7 mmo, the molar ratio of CDen to Cu was 1.0. According to X-ray diffraction, the interlayer distance of this composite was 33.4 Å. Furthermore, ESR measurement,
As a result of model calculations of the structure of the organic layer, it was found that in this complex, a dimer (complex) consisting of two CDen molecules and two copper () atoms forms a two-dimensional hexagonal close-packed structure between the silicate layers. Presumed. The X-ray diffraction pattern of this composite was as shown in FIG. A
indicates Cu()-montmorillonite, B and C indicate the composite in a wet state and a dry state, respectively.

[Brief explanation of the drawing]

An X-ray diffraction pattern of the composite obtained in Example 1,
A is Cu()-montmorillonite, B and C are the diffraction patterns of the composite in a wet state and a dry state, respectively.

Claims (1)

[Claims] 1 General formula (X, Y) _2~3 Z ₄ O ₁₀ (OH) ₂ ·mH ₂ O(W) _n (where X is A, Fe(), Mn() and
Trivalent metal selected from Cr (), Y is Mg, Fe
(), Mn () and divalent metal selected from Ni,
Z is Si or A, W is Cu(), K, Na and
Metal selected from Ca, m represents the number of water molecules)
A crystalline composite of a montmorillonite-cyclodextrin compound, which is made of montmorillonite having a layered structure shown in the following, and a cyclodextrin compound present between the layers. 2 General formula (X, Y) _2~3 Z ₄ O ₁₀ (OH) ₂・mH ₂ O(W) _n (However, X is A, Fe (), Mn () and
Trivalent metal selected from Cr (), Y is Mg, Fe
(), Mn () and divalent metal selected from Ni,
Z is Si or A, W is Cu(), K, Na and
Metal selected from Ca, m represents the number of water molecules)
1. A method for producing a crystalline composite of a montmorillonite-cyclodextrin compound, which comprises moistening a montmorillonite powder having a layered structure shown in the following formula with an aqueous solution of a cyclodextrin compound.