JPS61195125A - Aromatic polyimide and production thereof - Google Patents

Abstract

PURPOSE:To obtain an aromatic polyimide containing a specific recurring unit, having excellent solubility in polar organic solvent and heat-resistance, and suitable as electrical insulation material, by polymerizing a specific aromatic tetracarboxylic acid component with a specific aromatic diamine component in a polar organic solvent. CONSTITUTION:An aromatic polyimide containing the recurring unit of formula II or formula III (preferably containing only said recurring unit) is produced by polymerizing (A) an aromatic tetracarboxylic acid component composed mainly of biphenyltetracarboxylic acid compound (e.g. 2,3,3',4'- biphenyltetracarboxylic acid) or benzophenonetetracarboxylic acid compound (e.g. 2,3,3',4'-benzophenonetetracarboxylic acid) and (B) an aromatic diamine component composed mainly of the aromatic diamine of formula I in a polar organic solvent (e.g. N,N'-dimethyl sulfoxide). EFFECT:A coating layer and a film can be produced easily. USE:Suitable as a protective film for electric material such as the insulation film for circuit pattern board.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention provides an electrically conductive material that has excellent mechanical strength, electrical insulation, etc., and particularly excellent solubility in organic polar solvents and heat resistance. The present invention relates to a novel aromatic polyimide that can be suitably used as an insulating material, and a method for producing the same.

[Prior art]

Conventionally, various types of aromatic polyimides have been known; for example, (a) pyromellitic acid dianhydride and aromatic diamine such as 4,4'-diaminodiphenyl ether; Acid-based polyimide, (b) benzophenetetracarboxylic acid-based polyimide obtained from benzophenonetetracarboxylic dianhydride and an aromatic diamine such as 4.4'-diaminodiphenyl ether, (C) biphenyltetracarboxylic dianhydride and 4
．． Biphenyltetracarboxylic acid polyimides obtained from aromatic diamines such as 4'-diaminodiphenyl ether have been known.

However, many of the conventionally known (a) pyromellitic acid-based aromatic polyimides have virtually no solubility in organic polar solvents. Polyimide must be melted and used, and after removing the solvent, it must be imidized to form polyimide, and the storage stability of the precursor solution is not sufficient.
Film forming conditions were also limited, making film forming difficult. In addition, although the known (bl benzophenone tetracarboxylic acid aromatic polyimide) has excellent solubility in organic solvents, it does not have sufficient heat resistance for practical use. Although group polyimides have considerable solubility in organic solvents, they have a second-order transition point around 300° C. and do not have sufficient heat resistance during use.

[Requirements and effects of the present invention]

This invention relates to an aromatic polyimide characterized by mainly having a structural formula or a repeating unit represented by the structural formula, and an aromatic tetracarboxylic acid component whose main component is biphenyltetracarboxylic acids or benzophenonetetracarboxylic acids. and an aromatic diamine component whose main component is 9,10-bis(p-aminophenyl)anthracene (aromatic diamine) represented by the structural formula, in an organic polar solvent. The present invention relates to a method for producing an aromatic polyimide mainly having repeating units represented by structural formula (1) or (II).

The aromatic polyimide of this invention is a novel aromatic polyimide obtained by polymerization of a conventionally unknown tetracarboxylic acid component and an aromatic diamine component.

In the aromatic polyimide of the present invention, its precursor, aromatic polyamine chloride, is soluble in an organic polar solvent, and the aromatic polyimide itself can also be dissolved in an organic polar solvent. It is easy to form a coating film or to produce a polyimide film using a solution of the aromatic polyimide or aromatic polyamic acid of the invention.

Further, the aromatic polyimide of the present invention has a high thermal decomposition initiation temperature of about 460°C or higher, and further,
Substantially no secondary transition temperature is shown by DSC measurement, and as a result, it has excellent practical heat resistance, such as when used to form an insulating film on the surface of a conductive wiring pattern.

[Detailed explanation of each requirement of the present invention]

The aromatic polyimide of this invention has the structural formula (1) or (
If) is preferably an aromatic polyimide having at least 80 mol %, particularly preferably 90 mol % or more of repeating units represented by structural formula (1) or (II).
It is preferable that the aromatic polyimide has substantially only repeating units represented by the following.

As the aromatic polyimide, for example, 2°3.3
', a polymer obtained by polymerization etc. from 4°-biphenyltetracarboxylic acids and aromatic diamine,
An aromatic image polyimide mainly having repeating units represented by the structural formula, or a polymer obtained by polymerization etc. from 3.3'', 4.4'-biphenyltetracarboxylic acids and aromatic diamine, which has the structural formula An aromatic image polyimide mainly having the repeating unit shown, or a polymer obtained by polymerization etc. from 3.3', 4.4'-benzophenone tetracarboxylic acids and aromatic diamine, which has an aromatic image shown by the structural formula Examples include group polyimide.

The aromatic polyimide of this invention has a logarithmic viscosity (measurement temperature:
30℃, concentration: 0.5g/100mj! solvent, solvent;■
-methyl-2-pyrrolidone) is 0.2 to 5. Especially, it is about 0.3 to 3.0.

The aromatic polyimide of the present invention includes, for example, an aromatic tetracarboxylic acid component mainly containing biphenyltetracarboxylic acids or benzophenonetetracarboxylic acids;
The aromatic diamine component mainly containing the aromatic diamine represented by the structural formula (I[) is polymerized in approximately equimolar amounts in an organic polar solvent at a polymerization temperature of about 80° C. or lower to form a polyimide precursor. An aromatic polyamic acid is produced, and then a dried film formed by applying the aromatic polyamic acid or a solution of the aromatic polyamic acid is treated with a chemical imidizing agent (e.g., acetic anhydride, pyridine, etc.). or high temperatures of about 120°C or higher (particularly 140 to 22°C)
It can be produced by imidizing it by heating to a temperature of 0° C.) to produce an aromatic polyimide having a repeating unit represented by the above-mentioned structural formula (f).

Further, the aromatic polyimide of the present invention can be prepared by mixing the aromatic tetracarboxylic acid component and the aromatic diamine in approximately equal moles in an organic polar solvent in the presence of an imidizing agent, or in the presence of an imidizing agent.
An aromatic polyimide having a repeating unit represented by the structural formula (I) or (n) can also be produced by performing polymerization and imidization in one step at a high temperature of 20° C. or higher.

The above biphenyltetracarboxylic acids include 2.3
．． 3', 4'-biphenyltetracarboxylic acid or its acid dianhydride, 3,3°, 4,4''-biphenyltetracarboxylic acid or its acid dianhydride, 2.2', 3.3°
- biphenyltetracarboxylic acid or its acid dianhydride,
Alternatively, it may be an acid derivative such as an esterified product or an acid chloride of these acids, and the above-mentioned benzophenonetetracarboxylic acids include 2,3.3',4°-benzophenonetetracarboxylic acid or its acid dianhydride. , 3.3'
, 4,4'-benzophenonetetracarboxylic acid or its acid dianhydride, or acid derivatives such as esters and acid chlorides of these acids.

As the aromatic tetracarboxylic acid component or aromatic diamine component used in the production of the aromatic polyimide of the present invention, in addition to the above biphenyltetracarboxylic ms, other tetracarboxylic acids or an aromatic compound represented by the structural formula (III) may be used. It may also contain aromatic diamines other than group diamines.

The aromatic diamine represented by the structural formula (III) used in the production of the aromatic polyimide of the present invention can be prepared by a conventionally known method (Bull, soc, chim, Fra
nce 1951, 727-32), i.e., anthraquinone is heated at about 150-220°C in the presence of excess aniline and aniline hydrochloride.
It can be suitably produced by a method of producing by heating reaction for 1 to 20 hours (particularly 2 to 15 hours).

Examples of organic polar solvents used in the polymerization reaction in producing the aromatic polyimide of the present invention include N,N-dimethylsulfoxide, N,N-dimethylformamide, N,
N-diethylformamide, N,N-dimethylacetamide, N,N-diethylacetamide, N-methyl-2
-pyrrolidone, hexamethylene phosphoramide, tocresol, T-butyrolactone, p-chlorophenol and the like.

The aromatic polyimide of the present invention can be used, for example, as a solution dissolved in an organic polar solvent, or as a solution (fest) in which its precursor (aromatic polyamic acid) is dissolved in an organic polar solvent, and the solution is coated on the object to be protected. Rotary coating machine on the surface of
A coating layer is formed by coating with a printing machine, etc., and then, in order to remove the solvent in the coating layer, it is heated to about 50°C or higher and relatively dried in a short period of time (if necessary, during this drying or Immediately after drying, the polymer is heated to 200°C or higher, especially 300°C or higher to imidize the polymer) to form a dry film (protective layer) made of aromatic polyimide, and is used especially for electronic materials. It is used as a protective film for, for example, an insulating film for wiring pattern boards.

In the above-mentioned festival, an adhesion aid may be added as appropriate in order to improve the adhesion to the object to be coated.

In this invention, the aromatic polyimide mainly having repeating units represented by the structural formula (mV) has particularly excellent solubility in organic polar solvents and also has excellent heat resistance. For applications such as, it is possible to easily prepare an aromatic polyimide solution with good coating film formation properties, and the aromatic polyimide formed by coating has sufficient heat resistance, making it extremely practical. suitable for

[Reference Examples, Examples and Comparative Examples]

Synthesis Example 1 9.10-bis(p-aminophenyl)anthracene [
Synthesis of aromatic diamine represented by structural formula (III) 90 ml of aniline and 24 g of aniline hydrochloride were added to 12.49 g of anthraquinone, and the mixture was heated at 185°C for 12 hours.
After heating and reacting, it was cooled, and the resulting precipitate was separated by filtration using a Puchner funnel, further washed with methanol, and dried under reduced pressure to collect 12.4 g of green powder. .

This powder was extracted with 200 mJ of benzene, and the extract was separated and purified by column chromatography (Wako Gel (C-200) manufactured by Wako Pure Chemical Industries, Ltd.) using benzene as a developing solvent. .3g (
A yield of 33.8 mol%) was obtained.

Regarding the separated and purified product, infrared absorption spectrum, H-N
As a result of MR spectra, gravimetric analysis, elemental analysis, etc.
The separated and purified product was confirmed to be 9.10-bis(p-aminophenyl)anthracene.

The results of elemental analysis are shown below.

HN Actual value (%) 86.19 5.71 7.50 Calculated value (%) 86.66 5,56 7.78 Example I N-methyl-2-pyrrolidone (NMP) 12.0 mj!
To, 1.054 g of 2.3.3',4'-biphenyltetracarboxylic dianhydride, 1.291 g of 9.10-bis(p-aminophenyl)anthracene, and 20
The mixture was stirred at ℃ for 5 hours to produce aromatic polyamic acid.

The logarithmic viscosity of this aromatic polyamic acid was 1.45.

Next, to 12.0 g of this aromatic polyamic acid solution,
After diluting by adding 30.3 ml of NMP, 6.
71g, pyridine 2.57g and benzene 6゜1m
1 was added and reacted at 50°C for 2 hours to imidize.
Aromatic polyimide was produced.

Add methanol dropwise to this aromatic polyimide solution,
When added in excess, the aromatic polyimide precipitated and was filtered and separated to recover yellow aromatic polyimide powder.

This aromatic polyimide dissolved in NMP in an amount of 20% by weight or more at 25°C, and the thermal decomposition onset temperature of this aromatic polyimide was 480°C (measured with a DuPont 910 thermal analyzer).

Example 2 3.3', 4.4' as aromatic tetracarboxylic acid component
An aromatic polyamic acid was produced in the same manner as in Example 1, except that -biphenyltetracarboxylic dianhydride was used.

The logarithmic viscosity of this aromatic polyamic acid was 1.64.

5. The aromatic polyamic acid solution, which is the reaction solution, was applied onto a glass plate using a spin coater, dried at 80°C for 10 minutes, and further heated at 300°C for 30 minutes to effect imidization.5. A 2μ thick film made of aromatic polyimide was formed.

This polyimide film was measured by infrared absorption spectrum and DSC, and the results are shown in FIGS. 1 and 4.

According to the measurement by DSC, no significant heat absorption or heat generation was observed in the polyimide film up to 450°C, and the thermal decomposition onset temperature was 470°C using a DuPont 910 thermal analyzer.
It was ℃.

This polyimide film is about 5M in m-cresol.
It was dissolved at a rate of % or more.

Example 3 3.3' and 4.4' as aromatic tetracarboxylic acid components
-benzophenone tetracarboxylic dianhydride 1.107
An aromatic polyamic acid was produced in the same manner as in Example 1, except that 1.238 g of 9.10-bis(p-aminophenyl)anthracene was used as the aromatic diamine.

The logarithmic viscosity of this aromatic polyamic acid was 1.24.

A 2 μm thick film made of aromatic polyimide was formed in the same manner as in Example 2, except that this polyamic acid solution was used.

This polyimide film was measured by infrared absorption spectrum and DSC, and the results are summarized in the second section.
The polyimide film shown in FIG.
According to the measurement by SC, no significant endotherm or exotherm was observed up to 450°C, and the temperature at which thermal decomposition started using a DuPont 910 thermal analyzer was 465°C.

This polyimide film was added to m-cresol with approximately 5i
It was dissolved at a ratio of i amount % or more.

Example 4 67.7 ml of m-cresol, 2.3.3', 4
'-Biphenyltetracarboxylic dianhydride 6.908
g and 8.463 g of 9.10-bis(p-aminophenyl)anthracene were added and heated at 180°C in a nitrogen atmosphere.
The mixture was stirred for 7 hours while heating to remove water, thereby producing an aromatic polyimide.

This aromatic polyimide reaction solution was a viscous yellow-brown solution with a rotational viscosity of about 100 pores or more at 25°C.

Furthermore, when 70 g of m-cresol was further added to this aromatic polyimide solution to dilute the polymer concentration to approximately 10% by weight, the rotational viscosity of the diluted solution at 25°C was 11
There was 0 voice.

This diluted solution was applied onto a glass plate using a rotary coating machine, and the coating film was heated to 200°C and held at that temperature for about 30 minutes to remove the solvent, resulting in an aromatic polyimide film with a thickness of about 2μ. A film was formed.

This polyimide film was measured by infrared absorption spectrum and DSC, and the results were reported in the third section.
As shown in the figure.

According to the measurement by DSC, no remarkable heat absorption or heat generation was observed in the polyimide film up to 450°C, and the thermal decomposition onset temperature was 490°C using a DuPont 910 thermal analyzer.
℃, and the results are shown in FIG.

The tensile test results of this aromatic polyimide showed that the tensile strength was 12.2 kg/w', the elongation was 8.5%, and the initial elastic modulus was 300 kg/w2.

Comparative Example 1 0.88 g of pyromellitic dianhydride was used as the aromatic tetracarboxylic acid component, and 9.0 g was used as the aromatic diamine component.
10-bis(p-aminophenyl)anthracene 1.4
The polymerization reaction was carried out at different intervals in Example 1, except that 61 g of the polymer was used, but the reaction solution remained suspended due to gelation and did not become transparent, and the production of high molecular weight aromatic polyamic acid was difficult. It was practically not recognized.

[Brief explanation of drawings]

1 and 4 relate to an aromatic polyimide having a repeating unit represented by the structural formula (IV), and a second
The figure and FIG. 5 relate to an aromatic polyimide having a repeating unit represented by structural formula (V), and a third
The figure and FIG. 6 relate to an aromatic polyimide having a repeating unit represented by the structural formula (■).

Claims (2)

[Claims] (1) An aromatic polyimide characterized by having a repeating unit represented by the structural formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (I) or the structural formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (II). (2) An aromatic tetracarboxylic acid component whose main component is biphenyltetracarboxylic acids or benzophenonetetracarboxylic acids, and an aromatic diamine represented by the structural formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (III) as the main component. A method for producing an aromatic polyimide, which comprises polymerizing an aromatic diamine component in an organic polar solvent.