JP2003140209A - Nonlinear optical material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compound which is excellent in properties such as thermal stability and dissolving property and useful when applied for a nonlinear optical material. SOLUTION: The compound is a polymer for a nonlinear optical material containing a monomer unit expressed by formula (1). In the formula, X represents a halogen atom, m' is 1 or 2, R<1> represents a hydrogen atom or an alkyl group which may have a substituent, R<2> represents a phenylazo group having a substituent or a vinyl group having at least one cyano group, n is an integer of 1 to 12 and Ar represents a bivalent organic group.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nonlinear optical material used for an optical delay element, a wavelength conversion element, an optical switch, an optical modulation element, an optical amplifier, an optical memory, a dispersion compensator, a soliton generating element and the like.

[0002]

2. Description of the Related Art In the advanced information-oriented society, which is expected to grow more and more in the future, it is necessary to transmit large-capacity and precise information at high speed, high density and high efficiency.
In order to meet this demand, development of a technique using light, which is excellent in parallel progressability, spatial processing property, mass operability, high density property, etc., is expected. As a material supporting a communication technology using light, a non-linear optical material that enables wavelength control and phase control is drawing attention.

Non-linear optical materials can be roughly classified into inorganic non-linear optical materials utilizing absorption of lattice vibration and organic non-linear optical materials utilizing dipole moment. Organic non-linear optical materials are basically accompanied by lattice vibration. Since it does not exist, there is an advantage that a faster response is possible. As such a nonlinear optical material, for example, JP-A No. 11-80275 discloses a nonlinear optical material made of an acrylamide copolymer.

[0004]

The nonlinear optical material, which has been actively researched and developed in recent years, has the characteristics (thermal stability, solubility, durability, light loss, etc.) of the conventional nonlinear optical material. Was not always satisfactory. In particular, since the glass transition temperature (Tg) of a polymer used as a nonlinear optical material is low, an orientation relaxation phenomenon in which orientation is gradually lost due to thermal motion of molecular chains occurs,
There is a problem that the non-linear optical characteristics deteriorate. For example, regarding a non-linear optical material to which polymethylmethacrylate (PMMA) has been intensively studied as a polymer waveguide material, the glass transition temperature of PMMA is 100 ° C.
It is reported that the non-linearity developed by the poling treatment is rapidly deactivated at room temperature because of its low level. In view of the above matters, it is an object of the present invention to provide an organic non-linear optical material which is excellent in various properties such as thermal stability, solubility, durability and light loss.

[0005]

[Means for Solving the Problems] The inventors of the present invention have conducted extensive studies to solve the above problems, and as a result, copolymerization of a predetermined halogen-containing monomer and a dihydroxy compound gives a polymer having high thermal stability. It was further found that by introducing a cyanovinyl group or a phenylazo group into the side chain of the obtained polymer, it is possible to obtain a polymer for a nonlinear optical material having extremely excellent thermal stability.
The present invention has been completed based on such findings, and specifically has the following configurations.

The present invention has the following formula (1):

[0007]

[Chemical 4]

(In the formula, X is a halogen atom, and m is 2
Is an integer of 4 to 4, R ¹ is a hydrogen atom or an alkyl group which may have a substituent, and n is an integer of 1 to 12) (hereinafter, “halogenated aromatic compound”). Also described as "monomer").

The present invention also provides the following formula (2):

[0010]

[Chemical 5]

(In the formula, X is a halogen atom, m'is an integer of 0 to 2, R ¹ is a hydrogen atom or an alkyl group which may have a substituent, and n is 1 to 12). And Ar is a divalent organic group) is a polymer containing a monomer unit (hereinafter, also referred to as “polymer (II)”).

The present invention also provides the following formula (3):

[0013]

[Chemical 6]

(In the formula, X is a halogen atom, m'is an integer of 0 to 2, R ¹ is a hydrogen atom or an alkyl group which may have a substituent, and R ² is a substituent. Is a vinyl group having at least one cyano group, n is an integer of 1 to 12, Ar
Is a polymer containing a monomer unit represented by a divalent organic group (hereinafter, also referred to as “polymer (III)”).

Furthermore, the present invention is a non-linear optical material using the polymer (III).

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to a novel nonlinear optical material containing a monomer unit represented by the above formula (3). Such a polymer has excellent thermal stability and solubility, and has a high glass transition temperature (Tg) which is an index of thermal stability. Therefore, when applied to a non-linear optical material, the orientation relaxation phenomenon, which has been a problem in the past, can be suppressed, and excellent non-linear optical characteristics can be maintained. Hereinafter, the monomer and the polymer (II) used for the synthesis of the polymer (III) will be described in detail first, and the polymer (III) synthesized from them will be described in the latter stage.

As the monomer, a compound having a structure represented by the above formula (1) can be used.

X is a halogen atom. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is preferable in view of solubility and thermal stability. The halogen atom is introduced into the benzonitrile moiety, and the number (m) is an integer of 2-4. To retain many halogen atoms in the synthesized polymer and obtain a large thermal stability effect due to the presence of halogen atoms, m
Is preferably 3 or 4, and more preferably 4. X may be two or more different halogen atoms, and when different halogen atoms are used, m means the total number of halogen atoms.

The benzonitrile having a halogen atom introduced therein is bonded to an aminoalkoxy group [(Phe) (R ¹ ) N (CH ₂ ) _n O-] as shown in the above formula (1).

R ¹ is a hydrogen atom or an alkyl group which may have a substituent, and the alkyl group may be a linear alkyl group, a branched alkyl group or a cyclic alkyl group. The number of carbon atoms contained in the alkyl group constituting R ¹ is not particularly limited, but is preferably 1 to 12 in consideration of production cost and yield,
It is more preferable that the number is 6. The substituent can be appropriately selected depending on the desired characteristics of the target object and is not particularly limited, but a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), a cyano group, a nitro group, Examples thereof include a carboxy ester group. Specific examples of R ¹ include hydrogen atom, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tertiary butyl, pentyl, 2-methylpentyl, cyclopentyl, hexyl, cyclohexyl, heptyl, octyl, nonyl, decyl, undecyl, Dodecyl, 1-fluoroethyl,
1,1-difluoroethyl, 1,1,2,2-tetrafluoroethyl and the like can be mentioned.

In the alkylene group [(CH ₂ ) _n ] existing between the amino group and the oxygen atom, n is an integer of 1-12. Considering the manufacturing cost and yield, n is preferably 1-6.

The binding site of the halogen atom X and the aminoalkoxy group to the benzonitrile site is not particularly limited. The binding site may be appropriately determined in consideration of the types of raw materials used for the preparation of the monomer, the influence on the properties of the polymer (III) which is the final product, the ease of synthesis, and the like. When is used as a raw material of a monomer, it can be determined in consideration of ortho-meta-para orientation due to the induction effect and resonance effect of a halogen atom and a cyano group.

Specific examples of the monomer represented by the above formula (1) include 4- (2- (N-methylanilino) ethoxy) -2,3,5,6-tetrafluorobenzonitrile and 4- (2- (N-ethylanilino) ethoxy)-
2,3,5,6-tetrafluorobenzonitrile, 4-
(2- (N-butylanilino) ethoxy) -2,3
5,6-Tetrafluorobenzonitrile, 4- (2-
(N-isopropylanilino) ethoxy) -2,3
5,6-Tetrafluorobenzonitrile, 4- (2-
(N-hexylanilino) ethoxy) -2,3,5,6
-Tetrafluorobenzonitrile, 4- (2- (N-cyclohexylanilino) ethoxy) -2,3,5,6-
Tetrafluorobenzonitrile, 4-((N-ethylanilino) methoxy) -2,3,5,6-tetrafluorobenzonitrile, 4- (4- (N-ethylanilino) butoxy) -2,3,5,6- Tetrafluorobenzonitrile, 4- (2- (N-ethylanilino) ethoxy)-
2,3,5,6-tetrachlorobenzonitrile, 4-
(2- (N-ethylanilino) ethoxy) -2,3
5,6-Tetrabromobenzonitrile, 4- (2- (N
-Ethylanilino) ethoxy) -2,3,5,6-tetraiodobenzonitrile, 2- (2- (N-ethylanilino) ethoxy) -3,4,5,6-tetrafluorobenzonitrile, 3- (2- (N-Ethylanilino) ethoxy) -2,4,5,6-tetrafluorobenzonitrile, 4- (2- (N-ethylanilino) ethoxy)-
3,5,6-trifluorobenzonitrile, 4- (2-
(N-Ethylanilino) ethoxy) -2,3-dichloro-5,6-difluorobenzonitrile, 4- (2- (N
Examples include, but are not limited to,-(1,1,2,2-tetrafluoroethyl) anilino) ethoxy) -2,3-dichloro-5,6-difluorobenzonitrile.

Next, one embodiment of the method for producing the monomer represented by the above formula (1) will be described with reference to FIG. In the following description, for convenience of explanation, X
Is a fluorine atom, R ¹ is ethyl, m is 4, m ′ is 2, n is 2, and the introduction site of R ² is the 4-position (para-position). However, it goes without saying that the present invention is not meant to be limited to these.

First, pentafluorobenzonitrile and 2- (N-ethylanilino) ethanol are prepared as raw materials. As these raw materials, commercially available compounds can be used, and they may be synthesized according to known methods. By reacting these, the monomer represented by the above formula (1) can be obtained. The synthesis is tetrahydrofuran, diethyl ether, diisopropyl ether, dioxane,
It can be carried out in a solvent such as acetonitrile, acetone, N-methyl-2-pyrrolidinone. Further, a bond between a halogen and a hydroxyl group (-C-F + H-O- → -C-O-)
In order to proceed, a compound such as sodium hydride, potassium fluoride, triethylamine, potassium carbonate, sodium carbonate or calcium carbonate is added. The reaction is carried out in an inert atmosphere (nitrogen atmosphere, argon atmosphere, etc.)
And the temperature of the solution is 20 to 400 ° C., preferably 20 to 1
The temperature can be maintained at 00 ° C., followed by stirring to proceed. The reaction time will differ depending on other reaction conditions and the starting materials used, but it is usually 1 to 20 hours, preferably 2 to 10 hours.
It's time. Further, the reaction may be carried out under normal pressure or reduced pressure, but it is desirable to carry out the reaction under normal pressure from the viewpoint of equipment. The product can be isolated and purified using column chromatography. In order to improve the work efficiency of isolation and purification, it is advisable to remove the solvent from the reaction solution to the extent that the product does not precipitate.

The compounding amount of the compound used for producing the monomer is pentafluorobenzonitrile, 2- (N
-Ethylanilino) ethanol and sodium hydride may be mixed so that the mole numbers thereof are equal, and the solvent amount may be selected such that these compounds are completely dissolved.

A polymer (II) containing a monomer unit represented by the above formula (2) by copolymerizing the monomer represented by the above formula (1) and a dihydroxy compound.
Can be synthesized.

M'is an integer of 0-2. In order to allow a halogen atom to be present to enhance thermal stability, m ′ is preferably 1 or 2, and more preferably 2. When X consists of two or more different halogen atoms, m ′ means the total number of halogen atoms. In addition,
Since X, n and R ¹ are the same as in the case of the above formula (1), description thereof will be omitted.

Ar represents a divalent organic group, and examples thereof include groups represented by the following formula.

[0030]

[Chemical 7]

--CH ₂ CH ₂ CH ₂ CH ₂ -,-(CH ₂ C
_{H 2 O) p -CH 2 CH} 2 -, and, - (CH ₂ CH (C
_{H 3) O) p -CH 2} CH (CH 3) - ( Here, p is 0-10, preferably an integer of 0 to 3).

In the above examples, considering solubility and heat resistance,

[0033]

[Chemical 8]

A divalent organic group represented by: is preferred.

The molecular weight of the polymer (II) containing the monomer unit represented by the above formula (2) is not particularly limited, but the number average molecular weight is preferably 3,000 to 500,000, Number average molecular weight 10,000 to 1
More preferably, it is 0,000. This is because if the molecular weight is too low, sufficient thermal stability may not be obtained, and if it is too high, the viscosity of the solution containing the polymer may become too high, which may make work such as film formation difficult. Molecular weight is G
It can be measured using a known means such as a PC.

The polymer (II) of the present invention may have two or more kinds of monomer units represented by the above formula (2), and is a polymer derived from the polymer (II). Other monomer units may be included as long as the characteristic of (III) as a nonlinear optical material is not lost. However, the mass of the monomer unit represented by the formula (2) is 10 to 10 with respect to the total mass of the polymer (II).
It is preferably 0% by mass, more preferably 50 to 100% by mass. This is because if there are too few monomer units, the effect of the present invention may not be sufficiently obtained.
In order to maximize the effects of the present invention and facilitate the control of the manufacturing process, it can be said that 100% by mass is generally preferable. When two or more kinds of monomer units are used, they may be block-shaped or random-shaped.

Next, one embodiment of the method for producing the polymer (II) containing the monomer unit represented by the above formula (2) will be described with reference to FIG.

First, a monomer represented by the above formula (1) and a basic compound are prepared, and these are dissolved in an organic solvent.

The monomer may be either a single compound or a mixture of two or more kinds of compounds, but considering the purification process and the physical properties of the polymer to be synthesized,
Preference is given to using it as a single compound.

The basic compound is used to collect hydrogen fluoride produced during the reaction and accelerate the reaction. Examples of such basic compounds include potassium carbonate, calcium carbonate, potassium hydroxide, calcium hydroxide, potassium fluoride, triethylamine, tributylamine, pyridine and the like. The amount of the basic compound used is 0.1 to 5 with respect to 1 mol of the monomer used.
It is mol, preferably 0.5 to 2 mol.

Examples of the organic solvent include polar solvents such as N-methyl 2-pyrrolidinone, N, N-dimethylacetamide, acetonitrile, benzonitrile, nitrobenzene, nitromethane and methanol; and those polar solvents and non-polar solvents such as toluene and xylene. Examples thereof include a mixed solvent with a polar solvent. These organic solvents may be used alone or in the form of a mixture of two or more kinds. The concentration of the non-linear optical material monomer in the organic solvent is 1 to 4
It is 0% by mass, preferably 5 to 30% by mass. At this time, when toluene or other similar solvent is used in the initial stage of the reaction, water produced as a by-product during the reaction can be removed as an azeotrope of toluene regardless of the polymerization solvent.

Next, the solution containing the above compound is raised to the reaction temperature. The reaction temperature should be determined according to the compound to be used so that the reaction efficiency is optimum, and cannot be defined uniquely, but usually 20 to 1
It is carried out at a temperature of 80 ° C, preferably 40-160 ° C.

After adjusting the solution temperature to the reaction temperature, HO-
A dihydroxy compound represented by Ar-OH is added to the solution to start the copolymerization reaction. The reaction is usually performed under an inert atmosphere (such as a nitrogen atmosphere or an argon atmosphere) under the condition of 1
~ 48 hours, preferably 2 to 30 hours. Further, the reaction may be carried out under normal pressure or reduced pressure, but it is desirable to carry out the reaction under normal pressure from the viewpoint of equipment.

The dihydroxy compound represented by HO-Ar-OH is selected according to the structure of the target polymer for nonlinear optical material. As a specific example, 2,2-bis (4-vidroxyphenyl) -1,1,1,3,3,3
-Hexafluoropropane (6FBA), 4,4'-dihydroxydiphenyl ether (DPE), hydroquinone (HQ), bisphenol A (BA), 9,9-bis (4-hydroxyphenyl) fluorene (HF), phenolphthalein (PP), 9,9-bis (3-methyl-4-hydroxyphenyl) fluorene (MHF),
1,4-bis (hydroxyphenyl) cyclohexane (CHB), 4,4′-dihydroxybiphenyl (BP) and the like can be mentioned. When introducing two or more monomer units, two or more dihydroxy compounds may be added. The amount of the dihydroxy compound used is 0.1 to 5 mol, preferably 1 to 2 mol, based on 1 mol of the monomer used.

After the completion of the polymerization reaction, the solvent of the reaction solution is removed by distillation or the like, and the distillate is washed if necessary to obtain the desired polymer (II). The polymer (II) may be obtained by adding the reaction solution to a solvent in which the polymer has low solubility to precipitate the polymer as a solid, and separating the precipitate by filtration.

By modifying the aniline site of the monomer unit represented by the above formula (2), the above formula (3)
A polymer (III) containing a monomer unit represented by is obtained. In the above formula (3), X, m ′, R ¹ , n and Ar are as defined in the formula (2), and the explanation thereof is omitted.

R ² is a phenylazo group having a substituent or a vinyl group having at least one cyano group. The polymer (II) having the monomer unit represented by the above formula (2) basically has no optical nonlinear effect, but by introducing such a group into the aniline site, excellent optical nonlinear effect can be obtained. It can be a polymer having. Moreover, it also has extremely excellent thermal stability. The number of the substituents may be one or two or more, and in the case of having two or more substituents, each substituent may be different. The site into which R ² is introduced is not particularly limited. The binding site may be appropriately determined in consideration of the influence on the properties of the target polymer (III).

The substituent which the phenylazo group has is not particularly limited as long as it exhibits an optical nonlinear effect, but an electron-withdrawing substituent is preferable, and examples thereof include a nitro group, a cyano group, a halogen atom, -C = C (CN) ₂
And substituents having these (see the examples below). The phenylazo group may have two or more substituents. Specific examples of the phenylazo group having a substituent include 4-nitrophenylazo, 2-nitrophenylazo, 3-nitrophenylazo, 2-fluorophenylazo, 2,3-difluorophenylazo and 3-fluoro-.
2-nitrophenylazo,

[0049]

[Chemical 9]

And the like. Further, specific examples of the vinyl group having at least one cyano group include 1-cyanovinyl, 2-cyanovinyl, 1,2-dicyanovinyl, 2,2-dicyanovinyl, and tricyanovinyl.

The molecular weight of the polymer for nonlinear optical material represented by the above formula (3) is not particularly limited, but the number average molecular weight is preferably 3,000 to 500,000, and the number average molecular weight is 10,000-100,000
It is more preferably 0. This is because if the molecular weight is too low, sufficient thermal stability may not be obtained, and if it is too high, the viscosity of the solution containing the polymer may become too high, and work such as film formation may become difficult. . Molecular weight is G
It can be measured using a known means such as a PC.

The polymer (III) may have two or more kinds of monomer units represented by the above formula (3) as long as the characteristics as a nonlinear optical material are not lost. , And may have other monomer units. However, the mass of the monomer unit represented by the above formula (3) is 10 to 10 with respect to the mass of the entire polymer (III).
It is preferably 0% by mass, more preferably 50 to 100% by mass. This is because if there are too few monomer units, the effect of the present invention may not be sufficiently obtained.
In order to maximize the effects of the present invention and facilitate the control of the manufacturing process, it can be said that 100% by mass is generally preferable. When two or more kinds of monomer units are used, they may be block-shaped or random-shaped.

Next, one embodiment of the method for producing the polymer (III) containing the monomer unit represented by the above formula (3) will be described with reference to FIG.

First, the polymer represented by the above formula (2) (I
The starting compounds of I) and R ² are prepared. The raw material of R ² is
It needs to be selected depending on the type of R ^{2 to be} substituted. R
^{When 2} is a phenylazo group having a substituent,
The appropriately substituted nitroaniline is used. Specifically, 4-nitroaniline, 3-nitroaniline, 2-nitroaniline, 2-fluoroaniline, 3,4-dinitroaniline,

[0055]

[Chemical 10]

And the like can be used. On the other hand, R ²
When is a vinyl group having at least one cyano group, tetracyanoethylene, tricyanoethylene or the like can be used.

When introducing a phenylazo group having a substituent as R ² , known diazotization method and coupling method can be used. The case of introducing a 4-nitrophenylazo group will be described with reference to FIG. First, the amine is dissolved in dilute inorganic acid or suspended in salt form. The amine may be selected according to the intended product. For example, when introducing a 4-nitrophenylazo group,
4-nitroaniline may be used. The inorganic acid is not particularly limited, and hydrochloric acid is generally used. The solvent is not particularly limited as long as it dissolves the components to be mixed and does not generate impurities. It may be appropriately selected from ethanol, propanol, toluene and the like.

The solution is adjusted to the reaction temperature and sodium nitrite is added. The reaction temperature varies depending on the stability of the diazo compound, but is usually 0 to 15 ° C. Sodium nitrite may be added slowly dropwise. After completion of the dropping, the temperature is returned to room temperature, recrystallization is performed using diethyl ether or the like, and the diazotized amine can be collected by filtration.

The amounts of amine and sodium nitrite are generally adjusted so that the number of moles of amine and the number of moles of sodium nitrite are equal. The inorganic acid should theoretically be mixed so that 2.0 mol of protons are generated with respect to 1 mol of amine, but 2.5 to 3.0 mol may be mixed in order to prevent mixing of by-products. preferable.

Subsequently, the obtained diazoamino compound is used for coupling. A diazoamino compound dissolved in a solvent such as pyridine and a polymer (II) dissolved in a solvent such as N, N-dimethylacetamide are prepared. These are mixed under ice cooling and stirred. Then the reaction mixture is stirred at room temperature to terminate the reaction. The stirring time should be determined according to the type and amount of the diazoamino compound used, but is usually about 30 minutes to 2 hours. The produced polymer (III) can be purified by reprecipitation, filtration, washing and vacuum drying.

When introducing the azo compound, it is not necessary to introduce the phenylazo group (R ² ) into all the monomer units represented by the above formula (2), and the phenylazo group is introduced into some of the monomer units. In this case, it is possible to obtain a polymer for a nonlinear optical material having sufficient thermal stability. The azo group introduction rate defined by the percentage of the number of phenylazo group-introduced monomer units with respect to the number of monomer units of the formula (2) contained in the polymer (II) is preferably 10 to 100%, and 30 ~
It is more preferably 100%. The azo group introduction rate can be calculated by elemental analysis, NMR and the like.

[0062] On the other hand, in the case of introducing a vinyl group having at least one cyano group as R ² is, R ² starting compounds and polymer (II), in addition to the solvent, is reacted under an inert atmosphere. As the R ² raw material compound, tetracyanoethylene, tricyanoethylene or the like can be used as described above, and the solvent is not particularly limited as long as it dissolves the components to be blended and does not generate impurities. Dimethylformamide or the like can be used. The reaction conditions may be 30 to 150 ° C. and 1 to 48 hours. After completion of the reaction, the product can be purified by reprecipitation, filtration, washing, and drying under reduced pressure.

When the vinyl group having a cyano group is introduced, it is not necessary to introduce the vinyl group (R ² ) having a cyano group into all the monomer units represented by the above formula (2), and some monomers may be used. If introduced in the unit,
It can be a polymer having sufficient thermal stability. However, considering the non-linear optical properties, polymer (II)
The cyanovinyl group introduction rate defined by the percentage of the number of monomer units having a cyano group-containing vinyl group introduced therein is preferably 10 to 100% with respect to the number of monomer units of the formula (2) contained in
It is more preferably 100%. The cyanovinyl group introduction rate can be calculated by elemental analysis, NMR and the like.

The polymer for nonlinear optical material of the present invention can be used for nonlinear optical materials such as optical delay element, wavelength conversion element, optical switch, optical modulation element, optical amplifier, optical memory, dispersion compensator and soliton generating element. . As a method for manufacturing the nonlinear optical material, various known techniques may be applied depending on the intended use. Below, as an example thereof, a case of forming a non-linear optical material on a substrate will be briefly described.

First, a solution containing a polymer for a nonlinear optical material and a low temperature curing accelerator is applied on a desired substrate by a spin coating method or the like, and then dried by a method such as heating if necessary. Then, it is cured by heating in a temperature range of about 60 to 300 ° C. Regarding the heating time, 5 minutes to 3 hours is sufficient, though it depends on the type of solvent and curing accelerator used, heating temperature, film thickness and the like. By this heat treatment, the solvent components remaining in the coating film are volatilized,
The low temperature curing accelerator is volatilized by evaporation, sublimation, decomposition, etc. to form a nonlinear optical material.

[0066]

EXAMPLES Next, the effects of the present invention will be demonstrated by examples. However, it goes without saying that the technical scope of the present invention is not limited to the following examples.

<Example 1> 1. Monomer Synthesis In a three-necked flask (100 ml), pentafluorobenzonitrile (10 g; 0.052 mol), 2- (N-
Ethylanilino) ethanol (8.55 g; 0.052
mol), sodium hydride (1.25 g; 0.052)
mol) and tetrahydrofuran (50 g) were added. This was stirred at room temperature for 5 hours. The solvent, tetrahydrofuran, was concentrated and purified by column chromatography to obtain 8.41 g of 4- (2- (N-ethylanilino) ethoxy) -2,3,5,6-tetrafluorobenzonitrile. The yield was 48%. In addition, FIG. 1 shows the ¹ H-NMR spectrum of 4- (2- (N-ethylanilino) ethoxy) -2,3,5,6-tetrafluorobenzonitrile.

2. Synthesis of Polymer (II) In a three-necked flask (50 ml) equipped with a reflux tube and a Dean Stark trap, 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexa Fluoropropane (1 g; 2.97 mmol), potassium carbonate (0.21 g; 1.49 mmol), N-methyl 2-pyrrolidinone (8 g), and toluene (5 g) were added. This mixed solution was azeotropically dehydrated at 130 ° C. for 2 hours under a nitrogen stream. Then, toluene was distilled off, and when the temperature of the reaction solution reached 95 ° C., 4- (2- (N-ethylanilino) ethoxy) -2,3,5,6-tetrafluoro synthesized by the above-mentioned method. Benzonitrile (1.01 g; 2.97 mmol) was added. This is 9
The reaction was allowed to proceed by stirring at 5 ° C for 25 hours. After the reaction was completed, this solution was poured into a 1% aqueous acetic acid solution. The precipitated polymer (II-1) was filtered off, washed with distilled water and methanol, and then dried under reduced pressure. The concentration of the polymer (II-1) is 2
It was dissolved in N-methyl 2-pyrrolidinone so as to be 0% by mass, and this solution was poured into methanol and purified by a reprecipitation method. The mass of the obtained polymer (II-1) was 1.6.
With 5 g, the yield was 87.6%. Further, the glass transition temperature was measured and found to be 109 ° C.

3. Synthesis of Polymer (III) In a three-necked flask (25 ml), the polymer (II-1) (1.5 g) purified by the above method, tetracyanoethylene (0.33 g; 2.60 mmol), and Dimethylformamide (20 g) was added, and after purging with nitrogen, 70
Stir at 24 ° C. for 24 hours. After cooling, methanol (200
g), and the mixture was filtered and dried under reduced pressure. The yield of the obtained polymer (III-1) (NLO polymer 1) was 1.
It was 61 g. The glass transition temperature was 167 ° C.

Example 2 A polymer (II-2) was prepared in the same manner as in Example 1 except that the reaction temperature for synthesizing the polymer (II-1) was 120 ° C. and the reaction time was 44 hours. ) Was synthesized. The yield of the polymer (II-2) was 1.77 g, and the yield was 93.9%. The glass transition temperature was 127 ° C.

Further, using the polymer (II-2) (1.5 g), the polymer (III-2) was prepared in the same manner as in Example 1.
(NLO polymer 2) was synthesized. The yield of the obtained NLO polymer 2 was 1.63 g. The glass transition temperature was 163 ° C.

Example 3 A polymer (II-3) was prepared in the same manner as in Example 1 except that the reaction temperature for synthesizing the polymer (II-1) was 120 ° C. and the reaction time was 46 hours. ) Was synthesized. The yield of the polymer (II-3) was 1.81 g, and the yield was 96.0%. The glass transition temperature was 135 ° C.

4-Nitroaniline (0.33 g; 2.36 mmol) and ethanol (2 g) were mixed in a three-necked flask (25 ml), and ethanol (0.1 g) saturated with hydrogen chloride was added. While stirring this mixed solution under ice cooling, sodium nitrite (0.16 g; 2.3
6 mol) was slowly added dropwise while keeping the solution temperature at 0 to 5 ° C. After the dropping is completed, the solution temperature is returned to room temperature and 10
Let stand for a minute. Then, diethyl ether was added to precipitate crystals, which were collected by filtration.

The precipitated crystals and pyridine (2 g) were mixed with 3
A one-necked flask (25 ml) was placed and mixed. While stirring this mixture under ice cooling, the polymer (II-3) (1.5
A solution of g) in N, N-dimethylacetamide was added, and the mixture was further stirred under ice cooling for 1 hour. The reaction mixture was then stirred at room temperature for 1 hour. Hydrochloric acid (5 g) and ice (1
The reaction solution was added to the place where 00g) was stirred. The precipitated solid was filtered, washed twice with water (25 g), and dried under reduced pressure. The yield of the obtained polymer (III-3) (NLO polymer 3) was 1.55 g. The introduction rate of the azo group-introduced portion was 47%. The glass transition temperature is 177.
It was ℃.

Example 4 In a three-necked flask (50 ml) equipped with a reflux tube and a Dean Stark trap,
2,2-bis (4-hydroxyphenyl) propane (1
g; 4.38 mmol), potassium carbonate (0.30 g;
2.19 mmol), N-methyl 2-pyrrolidinone (1
0 g) and toluene (5 g) were added. This mixed solution was azeotropically dehydrated at 130 ° C. for 2 hours under a nitrogen stream. Then, toluene is distilled off, and the temperature of the reaction solution is 120
Upon reaching ° C, 4- (2- (N-ethylanilino) ethoxy) -2, synthesized by the method of Example 1,
3,5,6-Tetrafluorobenzonitrile (1.48
g; 4.38 mmol) was added, and the mixture was stirred at 120 ° C. for 48 hours to allow the reaction to proceed. After the reaction is complete, add 1% of this solution
Poured into aqueous acetic acid. The precipitated polymer (II-4) was filtered off, washed with distilled water and methanol, and dried under reduced pressure. The polymer (II-4) was dissolved in N-methyl-2-pyrrolidinone so that the concentration thereof was 20% by mass, and this solution was poured into methanol and purified by a reprecipitation method. The mass of the obtained polymer (II-4) was 2.05 g, and the yield was 8
It was 8.9%. The glass transition temperature was measured and found to be 91 ° C.

Further, using the polymer (II-4) (1.24 g), the polymer (III-
4) (NLO polymer 4) was synthesized. The obtained NLO
The yield of polymer 4 was 1.27 g. The introduction rate of the tricyanovinyl group was 89%. The glass transition temperature was 135 ° C.

Example 5 In a three-necked flask (50 ml) equipped with a reflux tube and a Dean Stark trap,
9,9-bis (4-hydroxyphenyl) fluorene (1 g; 2.85 mmol), potassium carbonate (0.20
g; 1.43 mmol), N-methyl 2-pyrrolidinone (8 g), and toluene (5 g) were added. This mixed solution was azeotropically dehydrated at 130 ° C. for 2 hours under a nitrogen stream. Then, toluene was distilled off, and the temperature of the reaction solution was 95
Upon reaching ° C, 4- (2- (N-ethylanilino) ethoxy) -2, synthesized by the method of Example 1,
3,5,6-Tetrafluorobenzonitrile (0.97
g; 2.85 mmol) was added, and the mixture was stirred at 95 ° C. for 22 hours to allow the reaction to proceed. After the reaction was completed, this solution was poured into a 1% aqueous acetic acid solution. The precipitated polymer (II-5) was filtered off, washed with distilled water and methanol, and then dried under reduced pressure. The polymer (II-5) was dissolved in N-methyl-2-pyrrolidinone so that the concentration thereof was 20% by mass, and this solution was poured into methanol and purified by a reprecipitation method. The mass of the obtained polymer (II-5) was 1.59 g, and the yield was 86.
It was 0%. The glass transition temperature was measured and found to be 148 ° C.

Using the polymer (II-5) (1.53 g), the polymer (III-
5) (NLO polymer 5) was synthesized. The obtained NLO
The yield of polymer 5 was 1.55 g. The glass transition temperature was 194 ° C.

Example 6 A polymer (II-6) was prepared in the same manner as in Example 5 except that the reaction temperature for synthesizing the polymer (II-5) was 120 ° C. and the reaction time was 45 hours. ) Was synthesized. The yield of the polymer (II-6) was 1.71 g, and the yield was 92.5%. The glass transition temperature was 176 ° C.

Further, using the polymer (II-6), a polymer (III-6) (NLO polymer 6) was synthesized in the same manner as in Example 1. The yield of the obtained NLO polymer 6 was 1.65 g. The introduction rate of the tricyanovinyl group was 92%. The glass transition temperature was 209 ° C.

Example 7 A polymer (II-7) was prepared in the same manner as in Example 5 except that the reaction temperature for synthesizing the polymer (II-5) was 120 ° C. and the reaction time was 46 hours. ) Was synthesized. The yield of the polymer (II-7) was 1.68 g, and the yield was 90.9%. The glass transition temperature was 165 ° C.

A polymer (III-7) (NLO polymer 7) was synthesized using the polymer (II-7) in the same manner as in Example 3. The yield of the obtained NLO polymer 7 was 1.57 g. The introduction rate of the azo group introduction part is 40
%Met. The glass transition temperature was 204 ° C.

The results of Examples 1 to 7 are shown in Table 1 below.
Show as.

[0084]

[Table 1]

<Example 8> The NLO polymer obtained in Example 2 was dissolved in toluene and spin-coated with ITO.
A film was formed on a slide coated with. The obtained film was heated to a temperature higher by 2 to 3 ° C. than the glass transition temperature, and 6.5 kV was applied by the corona charging method. The film thickness of the obtained film was measured using a surface roughness meter. Further, the intensity of the second harmonic (χ ⁽²⁾ ₃₃ ) was measured from the intensity of the second harmonic generated by the maker fringe method using a laser beam having a wavelength of 1.3 μm as a light source. At that time, an α-quartz crystal plate was used as a reference sample. The results are shown in Table 2.

<Examples 9 to 13> The NLO polymers obtained in Examples 3, 4, 6 and 7 were also formed into a film by the same method as in Example 8, and the film thickness and the intensity of the second harmonic wave were measured. It was measured. The NLO polymer obtained in Example 7 was also measured when the film thickness was changed. The results are shown in Table 2.

[0087]

[Table 2]

[0088]

The polymer for nonlinear optical material of the present invention is
Glass transition temperature (Tg) because halogen is introduced
And has excellent thermal stability. Therefore, the nonlinear optical material formed by using the polymer for nonlinear optical material of the present invention is less likely to cause the reduction in orientation relaxation due to the thermal motion of the molecular chain, and can maintain excellent nonlinear optical characteristics. It can be said that this characteristic of the present invention broadens the range of application of the nonlinear optical material, and has great significance for generalization of the nonlinear optical material.

[Brief description of drawings]

FIG. 1 is a synthetic scheme of a polymer for a nonlinear optical material of the present invention.

FIG. 2 is a ¹ H-NMR spectrum of 4- (2- (N-ethylanilinoethoxy) -2,3,5,6-tetrafluorobenzonitrile of Example 1.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Goshin Ushiwata             5-27-17 Mine, Yamato-cho, Wakabayashi-ku, Sendai City, Miyagi Prefecture             Nanso 3 (72) Inventor Kyotsugu Komatsu             3-14-13-702 Hachiman, Aoba-ku, Sendai City, Miyagi Prefecture F-term (reference) 2K002 CA06 HA20                 4H006 AA01 AA03 AB46 AB76                 4J005 AA21 BA00 BD05

Claims (4)

[Claims] 1. The following formula (1): (In the formula, X is a halogen atom, m is an integer of 2 to 4, R ¹ is a hydrogen atom or an alkyl group which may have a substituent, and n is an integer of 1 to 12. ) A halogen-containing aromatic compound represented by: 2. The following formula (2): (In the formula, X is a halogen atom, m ′ is an integer of 0 to 2, R ¹ is a hydrogen atom or an alkyl group which may have a substituent, and n is an integer of 1 to 12. Yes, Ar
Is a divalent organic group). 3. The following formula (3): (In the formula, X is a halogen atom, m ′ is an integer of 0 to 2, R ¹ is a hydrogen atom or an alkyl group which may have a substituent, and R ² is a phenylazo group having a substituent. Group or a vinyl group having at least one cyano group, n is an integer of 1 to 12, and Ar is a divalent organic group). 4. A non-linear optical material using the polymer according to claim 3.