RU2352595C2 - Method for producing polyamide acid solution based on 4,4'-diaminotriphenylamine - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: there is disclosed method for producing polyamide acid solution by polycondensation of mixed 4,4'-diaminotriphenylamine and aromatic diamines and 3,3',4,4'- benzophenontetracarboxylic acid dianhydride or aromatic tetracarboxylic acid dianhydrides in amide solvent with agitating. One aromatic diamine mixed with 4,4'-diaminotriphenylamine is 5(6)-amino-2-(4-aminophenyl)benzimidazole with polycondensation in total molar ratio of aromatic diamines to aromatic tetracarboxylic acid dianhydrides equal to 1.00: (≤1.00).

EFFECT: prevented polymer gelatination in producing bulk polyamide acid solution, possibility for industrial engineering, possibility for more concentrated polymer solutions available for coatings, films and fibres.

5 cl, 6 ex, 1 tbl

Description

The invention relates to macromolecular compounds, in particular to a method for producing a solution of polyamido acid based on 4,4'-diaminotriphenylamine used to form non-porous coatings on metal and ceramic substrates in the manufacture of circuit boards used in electronic technology, as well as for applying varnish coatings to wires, synthetic fibers and bundles of them, for the formation of films and fibers.

It is known that a polyamido acid solution is obtained by polycondensation of aromatic diamine and tetracarboxylic acid dianhydride in a polar solvent, moreover, dianhydride is taken in equimolar and with an excess of 1-5% molar relative to diamine (Astakhin V.V., Trezvov V.V., Sukhanova I.V. Electrical insulating varnishes, films and fibers. - M.: Chemistry, 1986. - 157 p.).

As a prototype, we consider a method for producing a polyamido acid solution used in the preparation of non-porous coatings by reacting 4,4'-diaminotriphenylamine (I) in an amide solvent or a mixture thereof with at least one diamine of the formula H ₂ NA-NH ₂ ( Ii) where

с диангидридом формулыA = meta-Ph, -Ph-Z-Ph-, where Z = -O-, steam -O-Ph-O-, meta -O-Ph-O-, -O-Ph-SO ₂ -Ph-O -,

with dianhydride of the formula

O = (CO) ₂ = Ph-X-Ph = (CO ₂ ) = O (III), where X = -CO-, para-C (O) -Ph-C (O), meta-C (O) -Ph-C (O) -, -O-Ph-C (O) -Ph-O-, -SO ₂ -, -O-Ph-SO ₂ -Ph-O-, or a mixture thereof with at least one of the dianhydrides of the formula

O = (CO ₂ ) = Ph-Y-Ph = (CO) ₂ = O (IV), where Y = -O-, steam -O-Ph-O-, meta -O-Ph-O-, σ- communication or X with X ≠ Y (RF Patent No.2019548, IPC C08G 73/10; publ. 15.09.94. Bull. No. 17).

The synthesis of polyamic acid is carried out by polycondensation in an amide solvent of 4,4'-diaminotriphenylamine or a mixture thereof with diamines of the indicated structure and 3,3'4,4'-benzophenone tetracarboxylic acid dianhydride or a mixture thereof with dianhydrides of the specified structure, the molar ratio of the sum of diamines and dianhydrides being taken equal to 1: 1.

The process of formation of polyamido acid proceeds according to the scheme:

Polyamide acid obtained using 4,4'-diamino-triphenylamine after heat treatment gives a non-porous polyimide coating, characterized by very high dielectric characteristics, mechanical strength, elasticity and adhesion to the substrate.

The disadvantage of this method is the tendency of a solution of polyamide acid based on 4,4'-diaminotriphenylamine and 3,3'4,4'-benzophenone tetracarboxylic acid dianhydride to gelation during polycondensation with a reaction mass of more than 500 cm ³ , which impedes its practical use.

When reproducing examples of the known method (prototype), when the volume of the reaction mass during the polycondensation was 160 cm ³ and the varnish concentration was about 10 wt.%, Stable fluid polymer solutions were obtained, suitable for applying to the substrate and forming coatings.

However, when trying to produce large amounts of varnish under the conditions of the prototype, about 730 g in a 2 dm ³ reactor with the aim of producing products based on it, jelly formation of polymer solutions unsuitable for the formation of thin-film coatings, films and fibers was observed. A similar phenomenon was observed when trying to produce 7.5 kg of varnish in a reactor with a volume of 10 dm ³ .

The formation of non-fluid, non-agitating jellies leads to a sharp increase in agitation resistance, failure of the electric motors of the reactor agitator drives, the need for manual unloading of elastic rubber-like jelly from the reactor and its subsequent disposal or decontamination.

Thus, the known method of obtaining the target product is suitable purely for laboratory use or for producing small batches of product.

The main technological characteristic of a solution of polyamic acid in an amide solvent (polyamic acid varnish) is the specific or logarithmic viscosity of a 0.5% solution of polyamic acid (Sokolov LB Fundamentals of the synthesis of polymers by polycondensation. - M .: Chemistry, 1979. - 236 p .; TU 6-05-1890-85 3.3'4,4'-benzophenone tetracarboxylic acid dianhydride). To ensure the possibility of effective application of varnish, the viscosity of a 0.5% polymer solution at the polycondensation stage should be in the range of 1.3-2.8. With jelly formation at the polycondensation stage, the viscosity of the polymer solution cannot be determined at all.

The aim of the present invention is to improve the technology for producing a concentrated solution of polyamic acid based on 4,4'-diaminotriphenylamine by preventing gelation at the stage of polycondensation.

This goal is achieved in that in the method for producing polyamic acid by polycondensation of a mixture of 4,4'-diaminotriphenyl amine with aromatic diamines and 3,3'4,4'-benzophenone-tetracarboxylic acid dianhydride or its mixture with aromatic tetracarboxylic acid dianhydrides in an amide solvent with stirring, 5 (6) -amino-2- (4-aminophenyl) benzimidazole is used as one of the aromatic diamines and polycondensation is carried out at the ratio of the sum of moles of aromatic diamines to the sum of moles of aromatic tetracarb dianhydrides acid acids equal to 1.00: (≤1.00).

According to the invention, besides 5 (6) -amino-2- (4-aminophenyl) benzimidazole (Ib), 4,4'-diaminodiphenyl oxide (Ic) can be used as an additive to 4,4'-diamino-triphenylamine (Ia) , bis-1,3- (4-amino-phenoxy) benzene (Id), para-phenylenediamine (Ie) or meta-phenylenediamine (If)

As an additive to 3.3'4,4'-benzophenone tetracarboxylic acid dianhydride (IIa), pyromellitic acid dianhydride (IIb), 3.3'4,4'-diphenyltetracarboxylic acid dianhydride (IIc), and 3.3 'dianhydride can be used 4,4'-diphenyl oxide tetracarboxylic acid (IId), 3,3',4,4'-diphenyl sulfonetetracarboxylic acid dianhydride (IIe) or bis (3,4-di-carboxyphenoxy) diphenylpropane-2,2 (IIf) dianhydride.

As the amide solvent, dimethylformamide (DMF), N, N-dimethylacetamide (DMAA), N-methyl-pyrrolidone (NMP) or mixtures thereof can be used.

The concentration of polyamic acid in the solution can vary between 5-18%, depending on the purpose.

A solution of polyamic acid can be used to obtain molded products or form film coatings immediately after polycondensation or after treatment with a mixture of acetic anhydride (UA) and triethylamine (TEA) in a molar ratio of the sum of aromatic amines: UA: TEA equal to 1: (0.4-0 9) :( 0.8-2.2). As a result, partial cyclization of 20 to 45% of the polyamide-acid units of the polymer chain into polyimide occurs. This treatment helps to increase the duration of storage of the solution without gelling and the formation of helics in the temperature range from -10 ÷ 30 ° C.

However, if the varnish is used for molding immediately after synthesis or for up to 1 month of storage at a temperature of 5-15 ° C, treatment with a mixture of UA and TEA may not be performed.

, полученных по предлагаемому способу, изменяются в интервале от 1,2 до 2,8 дл/г в зависимости от структуры реагентов, природы растворителя и концентрации раствора.Values of the logarithmic viscosity of 0.5% solutions of polyamido acids in an appropriate solvent

obtained by the proposed method, vary in the range from 1.2 to 2.8 DL / g depending on the structure of the reagents, the nature of the solvent and the concentration of the solution.

The invention is illustrated by the following examples.

Example 1. In a cylindrical reactor with a capacity of 2 DM ³ equipped with an effective stirrer, 32.22 g (0.117 g · mol) are introduced

4,4'-diaminotriphenylamine (Ia), 1.615 g (0.0072 gmol) 5 (6) -amino-2- (4-aminophenyl) benzimidazole (Ib), 11.173 g (0.0558 gmol) 4 , 4'-diamino-diphenyl oxide (Ic) and 508.4 cm ^{3 of} N-methylpyrrolidone (NMP). The molar ratio of diamines is Ia: Ib: Ic = 0.65: 0.04: 0.31. The mass is stirred for 30 minutes until the diamines are completely dissolved. Then in portions with effective stirring, while maintaining the temperature in the mass within 19-24 ° C, 57.98 g (0.180 g mol) of 3.3'4,4'-benzophenone tetracarboxylic acid dianhydride (IIa) are introduced over 40 minutes. The molar ratio of the sum of diamines to dianhydride IIa is 1.00: 1.00.

After complete addition IIa, the mass is stirred at 19-24 ° C for 1 hour.

1,83 дл/г.Then, a pre-prepared mixture consisting of 12.77 g (0.125 g mol) of acetic anhydride (UA), 20.96 g (0.21 g) is gradually introduced into the reaction mass at a temperature of 30-40 ° C during 40 minutes. · Mole) of triethylamine (TEA) and 86 cm ^{3 of} N-methylpyrrolidone (NMP). The molar ratio of the sum of diamines: UA: TEA = 1: 0.69: 1.15. At the end of the process, the mass is filtered through a Schott filter No. 160 at room temperature. 731.1 g of a 14.1% polyamic acid solution are obtained. Logarithmic viscosity of a 0.5% solution

1.83 dl / g.

1,35 дл/г.Example 2. In the reactor and under the conditions described in example 1, a polyamic acid solution is prepared using a mixture of three aromatic diamines -4,4'-diaminotriphenylamine (Ia), 5 (6) -amino-2- (4- aminophenyl) benzimidazole (Ib) and 4,4'-diaminodiphenyl oxide (Ic), taken in a molar ratio of Ia: Ib: Ic = 0.65: 0.04: 0.31. The loading of diamines is: Ia - 32.22 g (0.117 g · mol), Ib - 1.615 g (0.0072 g · mol), Ic - 11.173 g (0.0558 g · mol). 3.3'4,4'-benzophenone tetracarboxylic acid dianhydride (IIa) is introduced into the synthesis in an amount of 56.84 g (0.1764 g mol), which corresponds to a molar ratio of the sum of diamines: IIa = 1.00: 0.98. The NMP solvent is taken in an amount of 508.4 cm ³ . A mixture of acetic anhydride and triethylamine was introduced into the synthesis in the same amount as in Example 1. 730 g of a 13.95% polyamic acid solution were obtained. Logarithmic viscosity

1.35 dl / g

1,86 дл/г.Example 3. The synthesis is carried out under the conditions of example 2, but with a molar ratio of diamines Ia: Ib: Ic = 0.65: 0.33: 0.02. The loading of diamines is Ia - 32.22 g (0.117 g · mol), Ib - 0.807 g (0.0036 g · mol), Ic - 11.894 g (0.0594 g · mol). The loading of dianhydride IIa, NMP, acetic anhydride and triethylamine are the same as in Example 2. The molar ratio of the sum of diamines: IIa = 1.00: 0.98. 729.9 g of a 13.94% polyamic acid solution are obtained. Logarithmic viscosity

1.86 dl / g.

Example 4. The synthesis of a solution of polyamic acid is carried out under the conditions of example 2, but without adding a mixture of acetic anhydride and triethylamine. Instead, an equivalent amount of NMP is introduced.

1,92 дл/г.730 g of a 13.95% polyamic acid solution are obtained. Logarithmic viscosity

1.92 dl / g.

Example 5. The synthesis of a solution of polyamic acid is carried out under the conditions of example 1 in a reactor with a volume of 10 DM ³ . The reactor charge amounts to: Ia - 322.2 g (1.17 g · mol), Ib - 16.15 g (0.072 g · mol), Ic - 111.73 g (0.558 g · mol), NMP - 5, 1 dm ³ , IIa - 579.8 g (1.80 g · mol). The molar ratio of the sum of diamines: IIa = 1.00: 1.00. At the stage of partial cyclization of the charge: acetic anhydride 127.7 g (1.25 g · mol), triethylamine 209.6 g (2.10 g · mol), NMP - 0.86 dm ³ .

1,44 дл/г.7.3 kg of a 14.1% polyamic acid solution are obtained. Logarithmic viscosity

1.44 dl / g

2,03 дл/г.Example 6. The synthesis of a solution of polyamic acid is carried out under the conditions of example 2 in a reactor with a volume of 25 dm ³ . Obtain 18.2 kg of a 14.1% solution of polyamic acid. Logarithmic viscosity

2.03 dl / g.

Thus, the proposed method allows to stably obtain a solution of polyamido acid based on 4,4'-diaminotriphenylamine in an amide solvent under the conditions of the production process, large-scale transfer of technology, which is very important if it is necessary to increase the output of the polymer solution.

The entire polyamide-acid varnish obtained in Examples 1-6 was used to deposit a dielectric polyimide layer on aluminum metal substrates, which are used in the manufacture of hybrid integrated circuits for various electronic devices.

The resulting polyimide layers had high thermal, dielectric and mechanical characteristics:

- heat resistance - 430 ° C in air and up to 500 ° C in an inert atmosphere;

- volume resistance - 10 ¹⁵ -10 ¹⁶ Ohm · cm;

- dielectric constant 3.2-3.3 (1 kHz);

- dielectric loss tangent (2-4) · 10 ^-3 (1 kHz);

- dielectric strength> 1.6 · 10 ⁶ V / cm;

- the tensile strength of the film in tension 120-140 MPa;

- adhesion to an aluminum substrate> 25 MPa.

Additional examples 7-13 illustrating the proposed method are shown in the table.

The advantages of the proposed method compared to the prototype are the prevention of polymer gelation during the production of large volumes of a polyamic acid solution, which makes it possible to organize industrial production, the possibility of obtaining more concentrated polymer solutions suitable for coating, forming films and fibers.

Claims (5)

1. The method of obtaining a solution of polyamic acid by polycondensation of a mixture of 4,4'-diaminotriphenylamine with aromatic diamines and 3,3'4,4'-benzophenone tetracarboxylic acid dianhydride or its mixture with aromatic tetracarboxylic acid dianhydrides in an amide solvent with stirring, characterized in that as 5 (6) -amino-2- (4-aminophenyl) benzimidazole is used in one of the aromatic diamines in a mixture with 4,4'-diaminotriphenylamine and the polycondensation is carried out at the ratio of the sum of moles of aromatic diamines to the sum of moles of apo dianhydrides aticheskih tetracarboxylic acids equal to 1,00: (≤1,00). 2. The method according to claim 1, characterized in that 4,4'-diaminodiphenyl oxide, bis- is used as aromatic diamines in a mixture of 4,4'-diaminotriphenylamine and 5 (6) amino-2- (4-aminophenyl) benzimidazole 1,3- (4-aminophenoxy) benzene, paraphenylenediamine or metaphenylenediamine. 3. The method according to claim 1, characterized in that as the aromatic dianhydrides of tetracarboxylic acids mixed with 3,3'4,4'-benzophenone tetracarboxylic dianhydride, pyromellitic acid, 3,3'4,4'-diphenyltetracarboxylic acid dianhydrides are used, 3,3'4,4'-diphenyl oxide tetracarboxylic acid, 3,3'4,4'-diphenyl sulfonetetracarboxylic acid or bis (3,4-dicarboxyphenoxy) diphenylpropane-2,2 dianhydride. 4. The method according to claim 1, characterized in that as the amide solvent, N, N-dimethylformamide, N, N-dimethylacetamide N-methylpyrrolidone or mixtures thereof are used. 5. The method according to claim 1, characterized in that the obtained polyamide acid solution is treated with a mixture of acetic anhydride and triethylamine in the form of a solution in an amide solvent with a molar ratio of the sum of aromatic diamines: acetic anhydride: triethylamine equal to 1: (0.4-0.9 ) :( 0.8-2.2).