JP2962717B1 - Method for producing N-alkyl chitosan derivative, N-alkyl chitosan derivative, and polymer using the same - Google Patents

Abstract

An ultraviolet-curable N-alkylchitosan derivative is obtained, and the ultraviolet-curable N-alkylchitosan derivative is obtained, thereby obtaining a polymer applicable to a primer for electroless plating. SOLUTION: An N-alkylchitosan derivative obtained by reacting chitosan with a (meth) acrylic acid derivative having an aldehyde group is obtained.
-UV curing of the alkyl chitosan derivative to obtain a polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing an N-alkyl chitosan derivative having an ultraviolet-curable functional group using chitosan, an N-alkyl chitosan derivative having an ultraviolet-curable functional group, and this N-alkyl chitosan. The present invention relates to a polymer using a derivative.

[0002]

2. Description of the Related Art Chitosan is a deacetylated basic polysaccharide of chitin, and is obtained by heating chitin with a concentrated alkali. Chitin is a polysaccharide that constitutes skeletal components such as crustaceans such as shrimp and crabs, exoskeletons of insects, and shells, mollusks, and arthropods. It is one of the unused biological resources. For this reason, chitosan can be obtained in abundance from chitin, which is used as an enzyme-immobilized carrier, sustained-release agricultural and pharmaceutical carrier, a coagulation / collection agent for protein wastewater, a tannin absorber, and a biocompatible material. Absorbable sutures and wound dressings (artificial skin) for surgery have been put to practical use.

[0003] Therefore, if a polymerizable derivative or the like is obtained by using chitosan, its use range is expected to be widened, and it is expected that effective use of resources will be achieved.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a UV-curable functional group-containing N which can be used as a raw material for polymer synthesis.
To provide an N-alkyl chitosan derivative having a method of producing an alkyl chitosan derivative and an ultraviolet curable functional group, and further provide a primer for electroless plating, a contact lens, a dental material, an antibacterial paint, and a biodegradable An object of the present invention is to provide a polymer using an N-alkyl chitosan derivative having an ultraviolet curable functional group, which is expected to be applied to paints and the like.

[0005]

The above object is achieved by the present invention described below. (1) A method for producing an N-alkyl chitosan derivative having a UV-curable functional group by reacting chitosan with a (meth) acrylic acid derivative having an aldehyde group. (2) The (meth) acrylic acid derivative having an aldehyde group is 2-hydroxy-3- (4-formyl-2-methoxy) phenoxypropyl acrylate or 2-hydroxy-3- (4-formyl-2-methoxy) phenoxypropyl The method for producing an N-alkylchitosan derivative having a UV-curable functional group according to the above (1), which is methacrylate. (3) N-alkylchitosan derivatives having an ultraviolet-curable functional group represented by the formula (I).

[0006]

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[In the formula (I), R represents a hydrogen atom or a methyl group. n represents the degree of substitution of the N-alkyl group, and m + n
= 1. (4) N- having the ultraviolet-curable functional group of (3) above
A polymer using an N-alkylchitosan derivative having an ultraviolet-curable functional group, obtained by irradiating an ultraviolet-curable composition containing an alkylchitosan derivative with ultraviolet rays and curing the composition.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.

The N-alkyl chitosan derivative having an ultraviolet (UV) curable functional group according to the present invention is obtained by reacting chitosan with a (meth) acrylic acid derivative having an aldehyde group.

The (meth) acrylic acid derivative having an aldehyde group used in this case is preferably a compound having an aldehyde group capable of reacting with the amino group of chitosan and having a UV-curable acryloyl group or methacryloyl group. There is no limitation, and an aromatic aldehyde having an acryloyl group or a methacryloyl group is preferably used. Specific examples include 2-hydroxy-3- (4-formyl-2-methoxy) phenoxypropyl acrylate and 2-hydroxy-3- (4-formyl-2-methoxy) phenoxypropyl methacrylate. Such an acrylic acid derivative can be prepared by a known method (for example, J. Polym.
S. : Part A: Polym. Chem. , Vo
l. 25, 3063-3077 (1987)) and the methods described in Examples below.

On the other hand, the chitosan mentioned here also includes low molecular weight chitooligosaccharides such as glucosamine which is a constituent amino sugar and oligosaccharides thereof. Commercially available chitosan can be used as it is.

In these reactions, a hydrophilic solvent such as methanol is added to a dilute organic acid solution of chitosan such as formic acid or acetic acid,
Further, the solution proceeds by adding a solution of the above (meth) acrylic acid derivative and stirring for about 6 to 12 hours, and then adding a solution of a reducing agent such as sodium borohydride and stirring for about 6 to 12 hours. The amount ratio of chitosan to the above (meth) acrylic acid derivative is determined by the degree of N-alkylation of chitosan desired (that is, the degree of substitution of the N-alkyl group which is a (meth) acrylic acid-derived group). The reaction temperature may be between 0 ° C. and room temperature. After completion of the reaction, purification is performed to obtain the desired product. Identification of the reaction product
It can be carried out by infrared absorption spectrum (IR spectrum) and proton nuclear magnetic resonance spectra ⁽¹ H-NMR spectrum).

As the N-alkyl chitosan derivative obtained according to the above-mentioned production method of the present invention, there is a compound represented by the formula (I).

[0014]

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In the formula (I), R is a hydrogen atom or a methyl group. n represents the degree of substitution of the N-alkyl group which is a (meth) acrylic acid-derived group, and satisfies the relationship of m + n = 1. That is, when R is a hydrogen atom, chitosan and 2-hydroxy-3- (4-formyl-2-methoxy) phenoxypropyl acrylate are reacted, and when R is a methyl group, chitosan and 2-hydroxy- It is obtained by reaction with 3- (4-formyl-2-methoxy) phenoxypropyl methacrylate.

Specific examples of the compound represented by the formula (I) are shown below.

[0017]

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The polymer using the N-alkyl chitosan derivative having an ultraviolet (UV) curable functional group according to the present invention can be used in a UV-curable composition containing an N-alkyl derivative represented by the formula (I). It is obtained by irradiation and curing.
Other UV-curable compounds can be added to the UV-curable composition, and the type, amount, etc. may be selected according to the purpose and use.

The conditions for UV curing can be according to known methods. In this case, the addition of the polymerization initiator is effective,
Known compounds can be used as the polymerization initiator, and examples thereof include benzophenone, benzoin, acetophenone, benzoin methyl ether, benzoin ethyl ether, and methylbenzoyl formate.

The polymer obtained in this manner includes an antibacterial paint, a biodegradable paint, a primer for electroless plating,
It can be expected to be applied to medical materials such as contact lenses and dental materials.

[0021]

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

Example 1 Synthesis of N-alkylated chitosan derivative I-1 (1) Synthesis of 2-hydroxy-3- (4-formyl-2-methoxy) phenoxypropyl methacrylate (VMA) A reaction scheme is shown below.

[0023]

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7.6 g (50 mmol) of vanillin, 8.3 g (60 mmol) of potassium carbonate, a quaternary ammonium salt (eg, tetra-n-butylammonium iodide) (catalytic amount), and 40 ml of epichlorohydrin were added to tetrahydroxide. The suspension was suspended in furan THF (120 ml) and heated at 90 ° C. for 6 hours under reflux. After concentration, the extract was washed with water and purified by silica gel column chromatography. Crystallization from ethanol gave 6.5 g of pale yellow needle crystals (yield 62).
%).

5 g of the obtained crystals of the vanillin derivative (VE) and 2.5 ml of methacrylic acid (29.
5 mmol), 1 ml of triethylamine (7 mmol
l), hydroquinone monomethyl ether 400mg
(3.2 mmol) was dissolved in 100 ml of THF.
The mixture was heated at reflux at 6 ° C. for 6 days. After concentration, the extract was washed with water and purified by silica gel column chromatography. 3. crystallized from ethyl acetate to give pale yellow needles of the desired product (VMA)
6 g was obtained (yield 65.6%). The result of mass spectrometry: 294.11 (molecular weight 294.30,
C ₁₅ H ₁₈ O ₆ ) Elemental analysis: C, 61.22; H, 6.16; O,
32.62 (%)

[0026]

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(2) N-alkylated chitosan derivative I-
Synthesis of 1 Chitosan (Kimitsu Chemical, molecular weight 150,000, DAC100)
1.6 g (10 mmol) of acetate buffer (pH 4.
5) Dissolved in 120 ml and added 80 ml of methanol.
2.35 g of the above VMA dissolved in THF was added to this solution.
(8 mmol) was added. After stirring overnight, an aqueous solution in which 1.05 g of sodium borohydride was dissolved was added. After further stirring at room temperature overnight, washing with centrifugal water and washing with methanol were repeated, and finally, purification was performed by freeze-drying. The product was confirmed by elemental analysis, IR spectrum and ¹ H-NMR.

The degree of substitution of the product was calculated by ¹ H-NMR and elemental analysis, and the degree of substitution was 0.8.

FIGS. 1 and 2 show the IR spectrum and ¹ H-NMR spectrum of chitosan and the N-alkylated chitosan derivative I-1.

Example 2 (1) In the synthesis of 2-hydroxy-3- (4-formyl-2-methoxy) phenoxypropyl methacrylate (VMA) of Example 1, acrylic acid was used in place of methacrylic acid, -Hydroxy-3- (4-formyl-2-methoxy) phenoxypropyl acrylate (VAA) was synthesized in the same manner (yield 28.5%).

[0031] mass spectrometry, elemental analysis, IR ^{spectrum, 1}
It was identified by 1 H-NMR spectrum. The results of mass spectrometry and elemental analysis are shown below.

Results of mass spectrometry: 280.19 (molecular weight 2
_{80.27, C 14 H 16 O 6} ) Elementary analysis Results: C, 59.99; H, 5.75 ; O,
34.25 (%)

[0033]

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(2) Using this VAA, an N-alkylated chitosan derivative I-2 was synthesized in the same manner as the N-alkylated chitosan derivative I-1. The product was confirmed in the same manner, and the degree of substitution calculated in the same manner was 0.8.

Example 3 In the synthesis of VMA and VAA in Examples 1 and 2, instead of hydroquinone monomethyl ether, hydroquinone was used.
It is also possible to use each compound of phenothiazine and 2,6-di-t-butyl-4-methylphenol.

Example 4 The IR spectrum of N-alkyl chitosan after UV irradiation was measured as follows. (Preparation method of measurement sample) N-alkyl chitosan I-
1: 0.875 mg (0.19 mmol) was dissolved in a mixed solution of 2 ml of a 5% acetic acid aqueous solution and 1.5 ml of N-methyl-2-pyrrolidone (alkyl chitosan concentration: about 2%).
Benzoin ethyl ether 24mg as photopolymerization initiator
(0.1 mmol) was added, and the mixture was stirred and dissolved. Thereafter, UV irradiation was performed under the following conditions.

Lamp used under UV irradiation conditions : metal halide lamp, irradiation distance: 15c
m, output: 1.0 kW, irradiation time: 30 seconds The membrane obtained after UV irradiation was washed with methanol, dialyzed, and purified by freeze-drying. Jasco FT / IR-70
Measured by the KBr disk method according to 00.

The IR spectrum of the polymer thus obtained was measured for chitosan and N-alkylated chitosan derivative I-
1 is shown in FIG.

Example 5 A 1% solution of the above-mentioned N-alkyl chitosan derivative having a UV-curable functional group in Aronix M-5600 (Toa Gosei Chemical Industry) and Unidick V-9005 (Dainippon Ink Chemical Industry) in a ratio of 1: 1. And benzoin ethyl ether was added at a concentration of 5%. This solution was spray applied on an ABS plate. Using a metal halide lamp, output 1.0kW, irradiation distance 15cm, irradiation time 30
When UV irradiation was performed for 2 seconds, a good coating film was obtained.

Next, the ABS resin piece obtained as described above was treated with a palladium chloride solution (PdCl ₂ .2H ₂ O: 0.
(25 g / l, hydrochloric acid 5 ml / l) for 3 minutes, washed with water, plated in an electroless copper plating bath shown in Table 1 for 30 minutes, and then nickel-plated in a bath composition shown in Table 2 for 5 minutes. . As a result, a uniform copper / nickel plating layer having a copper plating thickness of 0.8 to 1.0 μm and a nickel plating thickness of 0.4 to 0.8 μm was obtained.

[0041]

[Table 1]

[0042]

[Table 2]

[0043]

According to the present invention, UV curable N
-An alkyl chitosan derivative is obtained. Therefore, a polymer using the same can be obtained, and can be applied to antibacterial paints, biodegradable paints, primers for electroless plating, contact lenses, dental materials, and the like.

[Brief description of the drawings]

FIG. 1. Chitosan, N-alkyl chitosan derivative I-
1 is a graph showing an IR spectrum of an N-alkylchitosan derivative after UV irradiation.

FIG. 2 Chitosan, N-alkyl chitosan derivative I-1
3 is a graph showing a ¹ H-NMR spectrum of the above.

Continuing from the front page (72) Inventor Masato Azumi 1-10-11 Shiba-Daimon, Minato-ku, Tokyo Shiba-Daimon Center Building Daishin Chemical Co., Ltd. (72) Inventor: Fumiaki Nakatsubo 25-58 Ichizuka Gokasho, Uji City, Kyoto Prefecture ( 58) Field surveyed (Int.Cl. ⁶ , DB name) C08B 37/08

Claims (4)

(57) [Claims] 1. A method for producing an N-alkyl chitosan derivative having a UV-curable functional group by reacting chitosan with a (meth) acrylic acid derivative having an aldehyde group. 2. The method according to claim 1, wherein the (meth) acrylic acid derivative having an aldehyde group is 2-hydroxy-3- (4-formyl-2-).
Methoxy) phenoxypropyl acrylate or 2-
The method for producing an N-alkyl chitosan derivative having a UV-curable functional group according to claim 1, which is hydroxy-3- (4-formyl-2-methoxy) phenoxypropyl methacrylate. 3. An N-alkyl chitosan derivative having a UV-curable functional group represented by the formula (I). Embedded image [In the formula (I), R represents a hydrogen atom or a methyl group. n
Represents the degree of substitution of the N-alkyl group, and satisfies the relationship of m + n = 1. ] 4. An N-alkyl chitosan having an ultraviolet-curable functional group obtained by irradiating an ultraviolet-curable composition containing the N-alkyl chitosan derivative having an ultraviolet-curable functional group according to claim 3 with ultraviolet light and curing the composition. Polymers using derivatives.