JPH06271516A - Fluorine-containing aromatic diamine and its production - Google Patents

Abstract

PURPOSE:To provide a novel colorless and transparent fluorinecontaining aromatic diamine having a low dielectric constant and useful as a starting raw material for polyimides, polyamides, polyamideimides, bismaleimides and epoxy resins excellent in moldability. CONSTITUTION:A fluorine-containing aromatic diamine of formula I or II. It is obtained by condensing a trifluoromethyl benzene derivative of formula III (X is halogen or nitro substituted at 3,5 or 2,4 positions based on CF3) with 3-amino-5-trifluoromethylphenol of formula IV in an aprotic solvent in the presence of a base. A polyimide containing the diamine of formula I or II as monomer units exhibits various good physical characteristics including high heat resistance, high melt flovability originated from the existence of the amino group at the meta position to the bond group, low dielectric constant and colorless transparency originated from the CF3 group. Since the CF3 group is placed at the meta position to the amino group, the lowering in the polymerization degree is not caused by electronic factors.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an aromatic diamine having a trifluoromethyl group and a method for producing the same.
These compounds can be used as starting materials for polyimides, polyamides, polyamideimides, bismaleimides and epoxy resins.

[0002]

2. Description of the Related Art Polyimide resins belong to the best class among organic polymers in various properties such as heat resistance, mechanical properties and adhesiveness, and by utilizing these properties, various heat resistant mechanical parts and It is well known that it is widely used in adhesives, electronic material parts and the like. On the other hand, however, the polyimide resin has problems that it has a higher coloring and a higher dielectric constant than a low dielectric resin such as Teflon. The resin is colored with high heat resistance and high reliability cables for optical communication,
This is an extremely important issue in the development of optical materials such as filters and liquid crystal display panels. Specifically, when the yellowness index (hereinafter abbreviated as YI), which is an index of yellowness, is used as a parameter, 4,4′-diaminodiphenyl ether and pyromellitic dianhydride polyimide (trade name, Kapton ) Is a polyimide (trade name, Upilex) consisting of 129,4,4′-diaminodiphenyl ether and biphenyltetracarboxylic dianhydride is a polyimide consisting of 125,3,3′-diaminobenzophenone and benzophenonetetracarboxylic dianhydride ( LRAC-TPI) is 50, which is extremely high.

For use in the above-mentioned various optical material applications, YI is 10 or less, preferably YI which is comparable to polycarbonate which is widely used in optical material applications at present.
It is desired to have a polyimide resin of about 4-8. Also,
The permittivity is a very important parameter in the field of electronic materials, and the permittivity of polyimide resins currently commercialized is 3.5 / 1 MHz for Kapton, 3.5 / 1 MHz for Upilex, and 3. for LRAC-TPI. 7/1 MH
z. At present, polyimide resin has already been used as an insulating material for a flexible printed circuit board, but with the recent high integration of electronic circuits, an insulating material having a lower dielectric constant, specifically, a dielectric constant of 2.9. A polyimide resin having a frequency of / 1 MHz or less is desired.

Both of the above two problems are caused by electron transfer in the resin. The permittivity can be improved by restricting the movement of electrons in the polymer main chain, and the coloring can be improved by cutting the co-system in the main chain. As a specific method, it is known that introduction of an electron-withdrawing fluorine atom into a polyimide molecular unit is effective. For example, an aromatic diamine containing a hexafluoroisopropylidene group is disclosed as a polyimide monomer for a low dielectric constant material (Japanese Patent Laid-Open No. 1-19).
0652). However, these aromatic diamines have industrial problems such as a multi-step synthetic method and insufficient heat fluidity when molding and processing a polyimide resin obtained from them. Further, as the diamine having a trifluoromethyl group in the aromatic ring, for example, 4,4′-bis (4-amino-5-trifluoromethylphenyloxy) biphenyl represented by the formula (5) (formula 4) is disclosed. (WO-840412).

[0005]

[Chemical 4] However, in this compound, the amino group is present at the para position of the ether bond, so that the conjugated system is extended, which causes an increase in the dielectric constant and a decrease in transparency, and the resulting polyimide has a rigid structure. There was a drawback that processing became difficult.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a fluorine-containing aromatic diamine which is a raw material of polyimide having low dielectric constant, colorless and transparent, and excellent in moldability.

[0007]

[Means for Solving the Problems] The present inventors have completed the present invention as a result of intensive studies for solving the above problems. That is, the present invention provides a fluorine-containing aromatic diamine represented by formula (1) (formula 5) or formula (2) (formula 5) (hereinafter abbreviated as APB-9F), and formula (3).
A trifluoromethylbenzene derivative represented by (Chemical Formula 6) and 3-amino-5-trifluoromethylphenol represented by the formula (4) (Chemical Formula 7) (hereinafter abbreviated as TFMAP)
The present invention relates to a method for producing a fluorine-containing aromatic diamine represented by the formula (1) or the formula (2), which is obtained by condensing a compound in an aprotic solvent in the presence of a base.

[0008]

[Chemical 5]

[0009]

[Chemical 6] (In the formula, X represents a halogen atom or a nitro group, and the substitution position of X is 3,5 or 2,4 position with respect to the trifluoromethyl group)

[0010]

[Chemical 7] The fluorinated aromatic diamine of the present invention is a novel compound.

The polyimide obtained by using the diamine of the present invention as a monomer unit has various physical properties such as high heat resistance and high melt fluidity resulting from the presence of the amino group in the meta position relative to the bonding group. , Shows low dielectric property derived from trifluoromethyl group, colorless transparency and the like. Furthermore, since the trifluoromethyl group, which is an electron-withdrawing group, is located at the meta position of the amino group, the degree of polymerization will not be reduced due to electronic factors.

The method for producing APB-9F of the present invention will be specifically described below. The above compound can be produced in high yield by reacting a trifluoromethylbenzene derivative with TFMAP in the presence of a base in an aprotic polar solvent.

A method for producing a trifluoromethylbenzene derivative, which is one of the raw materials, is known, and, for example, 3,5-dinitrobenzotrifluoride is produced by Journal of
American Chemical Society (J. Am. Ch
em. Soc. ) 74 , 3011-14, it is obtained by reacting a mixed acid with benzotrifluoride. Also, regarding TFMAP, the manufacturing method is the Journal of Chemical Society (J. Chem. So.
c. ) 1949, 3016-20, and is known. In the method of the present invention, TFMAP should be at least twice equivalent to the trifluoromethylbenzene derivative,
Considering the complexity of post-treatment, cost, etc., it is preferable to use 2 to 2.5 times equivalent amount.

The base used in the method of the present invention is an alkali metal carbonate, hydrogencarbonate, hydroxide or alkoxide, which is potassium carbonate, potassium hydrogencarbonate, potassium hydroxide, sodium carbonate or hydroxide. Examples thereof include sodium, sodium hydrogen carbonate, lithium carbonate, lithium hydroxide, sodium methoxide, potassium isopropoxide and the like. The amount of these bases used may be equivalent to or more than the hydroxyl group of phenol as a raw material, and specifically 1 to 2 equivalents. As the aprotic solvent used in the method of the present invention, formamide, N-methylformamide, N, N-dimethylformamide, N, N-diethylformamide, N, N-dimethylacetamide,
Examples include N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, dimethyl sulfoxide, sulfolane and the like. The amount of these solvents to be used is not particularly limited, but usually 1 to 10 times by weight of the raw material is sufficient.

In the method of the present invention, a copper powder and a copper compound or a phase transfer catalyst such as crown ether, polyethylene glycol, quaternary ammonium salt or quaternary phosphonium salt is used as a catalyst for promoting the reaction. But it doesn't matter. The reaction temperature is usually 80 to 25
The temperature is in the range of 0 ° C, preferably 100 to 220 ° C. As a general reaction method of the present invention, a predetermined amount of TFMAP, a base, and an aprotic solvent are charged, and after TFMAP is converted to an alkali metal salt, a trifluoromethylbenzene derivative is added and reacted, or Alternatively, any method may be used in which all the raw materials containing the trifluoromethylbenzene derivative are simultaneously added in advance, and the temperature is raised as it is to react. Moreover, the present invention is not limited to these and can be appropriately implemented by other methods.

As a method for removing water in the reaction system, nitrogen gas or the like is aerated to remove water during the reaction.
There is a method of exhausting the gas to the outside of the system, but generally, a method of using a small amount of benzene, toluene, xylene, chlorobenzene, etc. to remove it outside the system by azeotropic distillation is used.
The end point of the reaction can be determined by thin layer chromatography, high performance liquid chromatography or the like while observing the decrease of the raw materials. After completion of the reaction, after concentration, or as it is, the product is discharged into water or the like to obtain the target diamine.
This product can be purified by recrystallization with a solvent, sludging, or purification by column chromatography.

[0017]

EXAMPLES The method of the present invention will now be described in more detail by way of examples, which should not be construed as limiting the invention thereto. Example 1 A four-necked flask equipped with a thermometer, a reflux condenser, and a stirrer was charged with N, N-dimethylformamide (DMF) 290.
g, 3,5-dinitrobenzotrifluoride 36.9
g (0.156 mol), TFMAP 60 g (0.32
9 mol), potassium carbonate 33.1 g (0.239 mo)
1) was charged into each, and the temperature was raised to 145 ° C. with stirring, and then the reaction was performed at 145 ° C. for 14 hours. The purity of the target product at the end of the reaction was 63% by HPLC. After the reaction,
After cooling and removing inorganic salts by filtration, water 400
g was added and the organic layer was separated. Toluene 400 for the organic layer
g was added, and the mixture was washed with water and a 2% NaOH aqueous solution, and then toluene was distilled off. The obtained residue was purified by column chromatography to obtain 3,5-bis (3
-Amino-5-trifluoromethylphenoxy) trifluoromethylbenzene was obtained as a pale yellow solid. Yield 32 g, yield 41.3%, melting point 82-84 ° C ¹ H-NMR δ (CDCl ₃ , ppm): 3.93 ((1), 4H, s) 6.42-6.47 ((2)) 2H, t) 6.62 to 6.68 ((3), 4H, m) 6.77 to 7.82 ((4), 2H, t) 6.99 to 7.01 ((5), 2H , D) The numerical value in the parentheses represents the position of the following formula (Formula 8).

[0018]

[Chemical 8]

Example of use The diamine obtained in Example 1 and 2,2-bis (3,4)
-Dicarboxyphenyl) -1,1,1,3,3,3-
Hexafluoropropane dianhydride (6F-BA),
It was condensed to obtain a polyimide. The physical properties of the obtained film were as follows. -Glass transition temperature Tg: 190 ° C-Melting point Tm: None-Viscosity η: 0.54 dl / g (35 ° C) (polyimide 0.5g / 100 cc (N, N-dimethylacetamide))-Dielectric constant: 2.83 / 60Hz 2.81 / 3kHz 2.79 / 1MHZ.YI: 7

[0020]

According to the present invention, a low dielectric constant, colorless and transparent,
And, as a raw material for polyimide having excellent moldability,
It has become possible to provide a very useful fluorine-containing aromatic diamine.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akihiro Yamaguchi 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui Toatsu Chemical Co., Ltd.

Claims (2)

[Claims] 1. A fluorine-containing aromatic diamine represented by formula (1) (formula 1) or formula (2) (formula 1). [Chemical 1] 2. A trifluoromethylbenzene derivative represented by formula (3) (formula 2), and (In the formula, X represents a halogen atom or a nitro group, and the substitution position of X is 3,5 or 2,4 position with respect to the trifluoromethyl group) Formula (4) (Chemical Formula 3) The method for producing a fluorinated aromatic diamine according to claim 1, which is obtained by condensing 3-amino-5-trifluoromethylphenol represented by the formula (3) in the presence of a base in an aprotic solvent.