JPS6410021B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to polyimide compositions, particularly polyimide compositions suitable for film production. More specifically, the present invention relates to improving the solvent resistance of soluble polyimide films. That is, 3,3',4,4'-benzophenonetetracarboxylic dianhydride (hereinafter referred to as
BTDA) and tolylene diisocyanate (2,4-, 2,6-isomers and mixtures thereof)
(hereinafter abbreviated as TDI) to improve the solvent resistance of polyimide films soluble in organic solvents obtained by reaction with TDI. Polyimides are already known to have excellent properties such as high heat resistance and chemical resistance, as well as mechanical and electrical properties, and are particularly useful for films used at high temperatures, wire coatings, Very useful for adhesives, paints, laminates, etc. Aromatic polyimide molded products with good heat resistance are produced by reacting aromatic diamine and aromatic tetracarboxylic dianhydride in an organic polar solvent at a relatively low temperature to produce polyamic acid. After molding, it is common to thermally or chemically imidize to obtain a polyimide molded product. This is due to the infusibility and insolubility of polyimide, and the chemical reaction of imidization of polyamic acid during molding is accompanied by a process of desorption and evaporation of water, making it extremely difficult to set the conditions during molding.
Particularly during film molding, the phenomenon of film breakage is likely to occur due to molding shrinkage, strength of the polyamic acid film, etc. On the other hand, in recent years, several polyimides that are soluble in organic solvents and do not involve chemical reactions during molding have been developed. One of them is a polyimide obtained by reacting BTDA and TDI, which are one of the constituent components of the present invention. Since this polyimide can be molded in its polyimide form, only the solvent is removed during molding, and the moldability is very excellent. However, it has some drawbacks due to its solubility in organic solvents. One of them is solvent resistance. The inventors believe that this BTDA-
As a result of intensive studies aimed at improving the solvent resistance of TDI polyimide, the present invention was achieved. That is, the gist of the present invention is (A) 10 to 90 parts by weight of a polyimide containing BTDA and TDI as main reaction components; (B) an aromatic dianhydride obtained by the reaction of an aromatic diamine and an aromatic tetracarboxylic dianhydride; A polyimide composition comprising 10 to 90 parts by weight of polyamic acid has good moldability and is suitable for producing a polyimide film with improved solvent resistance. The polyimide that is component (A) of the present invention is a polyimide that is soluble in an organic polar solvent, and can be produced by the method described below. That is, approximately equal moles of BTDA and TDI are mixed in an organic polar solvent in a substantially anhydrous state at a temperature between room temperature and 200°C for 1 hour to 100°C.
A soluble polyimide is obtained by reacting for 3 to 50 hours, preferably at room temperature to 160°C. As the organic polar solvent, dimethyl sulfoxide,
N,N-dimethylformamide, N,N-dimethylacetamide, hexamethylphosphoramide,
Specific examples include N-methyl-2-pyrrolidone, tetramethylurea, and tetramethylene sulfone. It is also possible to replace a portion of BTDA with other tetracarboxylic dianhydrides. Examples include aromatic tetracarboxylic dianhydrides exemplified in the explanation of component (B), among which pyromellitic dianhydride is preferred. 50 mol% to maintain solubility
The following is used: Furthermore, aromatic polycarboxylic acid can also be used in place of a part of BTDA. As the aromatic polycarboxylic acid, trimellitic anhydride, terephthalic acid, isophthalic acid, etc. can be used. Although these can be used in any proportion, it is not preferable to use a large amount because the proportion of amide bonds increases and heat resistance, particularly heat deterioration resistance, decreases. The amount used should be kept at 50 mol% or less, preferably 30 mol% or less. It is also possible to replace a portion of TDI with other diisocyanate compounds. Such diisocyanate compounds include aromatic diisocyanates such as diphenylmethane diisocyanate, naphthalene diisocyanate, diphenyl sulfone diisocyanate, diphenyl ether diisocyanate, xylylene diisocyanate, o-tolidine diisocyanate, and phenylene diisocyanate, as well as hexamethylene diisocyanate and isophorone diisocyanate. Among them, 4,4'-diphenylmethane diisocyanate is preferred. The amount of these used is preferably 50 mol% or less to maintain the solubility of the polyimide produced. During the reaction, a catalyst can be used to shorten the reaction time. Tertiary amines such as tributylamine and dimethylbenzylamine, alkali metal alcoholates such as sodium methoxide and potassium methoxide, dibutyltin dilaurate,
Organic metal salts such as tin octenoate, etc. can be used. Component (A) in the composition of the present invention can also be produced by using corresponding diamines, tolylene diamines, etc. in place of TDI and other diisocyanates. Diamines that can be used with tolylene diamine include the diamines exemplified in the explanation of component (B), among which 4,4'-diaminodiphenylmethane, 4,
4'-diaminodiphenyl ether is preferred. Polyamic acid can be produced by reacting BTDA and tolylene diamine in the organic polar solvent at low temperatures, and then thermally or chemically imidized to produce the corresponding polyimide. The intrinsic viscosity of component (A) polyimide is N-methyl-
It is preferably in the range of 0.2 dl/g to 2 dl/g, measured at 30° C. in a 0.5 g/dl solution of 2-pyrrolidone. The polyamic acid which is the component (B) of the composition of the present invention is prepared by mixing about equimolar amounts of an aromatic diamine and an aromatic tetracarboxylic dianhydride in a substantially anhydrous state in an organic polar solvent at a relatively low temperature, e.g. It is produced by reacting at 150°C, preferably -20 to 100°C. As the organic polar solvent, the solvent used for producing component (A) is used. Preferably, the same solvent as component (A) is used. Examples of aromatic diamines include diaminodiphenylmethane, diaminodiphenylpropane, diaminodiphenyl ether, diaminodiphenyl sulfide, diaminodiphenyl sulfone, diaminodiphenyl ketone, naphthalene diamine, phenylene diamine, and tolylene diamine. , benzidine, dimethylbenzidine, dimethoxybenzidine, dichlorbenzidine, diaminoanthraquinone, xylylenediamine, etc., and one or more of these may be used. Preferably, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether,
4,4'-diaminodiphenyl sulfide may be used alone or together with para-phenylene diamine, naphthalenediamine, or benzidine derivatives. Further, aliphatic diamines such as hexamethylene diamine, octamethylene diamine, and bis(aminocyclohexyl)methane may be used in place of aromatic diamines. As an example of aromatic tetracarboxylic dianhydride,
Benzophenonetetracarboxylic dianhydride, pyromellitic dianhydride, naphthalenetetracarboxylic dianhydride, diphenyltetracarboxylic dianhydride, bis(dicarboxyphenyl)propane dianhydride, bis(dicarboxyphenyl)propane dianhydride, bis(dicarboxyphenyl)propane dianhydride, enyl) sulfone dianhydride, bis(dicarboxyphenyl) ether dianhydride, perylenetetracarboxylic dianhydride,
Examples include thiophenetetracarboxylic dianhydride, among which 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA) and pyromellitic dianhydride are preferred.
Alternatively, by replacing aliphatic tetracarboxylic dianhydride such as 1,2,3,4-butanetetracarboxylic dianhydride and cyclopentane tetracarboxylic dianhydride with a part of aromatic tetracarboxylic dianhydride, It can be used. The reaction is carried out at a relatively low temperature, but the reaction can also be carried out at a high temperature if precipitation of polyimide produced by the imidization reaction at high temperatures does not occur. The temperature is usually 150°C or lower, preferably 100°C or lower. The intrinsic viscosity of the aromatic polyamic acid (B) component is N
-Methyl-2-pyrrolidone in 0.5g/dl solution at 30℃
It is preferably within the range of 0.5 to 5 dl/g. The organic polar solvent used to prepare the composition of the present invention is a solvent that dissolves the polyimide and polyamic acid, which are the components (A) and (B) of the composition. Specifically, solvents that can be used in producing component (A) polyimide, such as dimethyl sulfoxide, N,N-
Mention may be made of dimethylformamide, N,N-dimethylacetamide, hexamethylphosphoramide, N-methyl-2-pyrrolidone, tetramethylurea, and tetramethylene sulfone. The composition of the present invention is prepared by mixing 10 to 90 parts by weight of the organic solvent-soluble polyimide as the component (A) and 10 to 90 parts by weight of the aromatic polyamic acid as the component (B) in the state of an organic polar solvent solution. can be easily obtained by Although various additives, diluents, etc. can be added to this composition, an auxiliary agent for imidization of polyamic acid is usually added. One is an acid anhydride such as acetic anhydride as a dehydrating agent, and the other is a tertiary amine such as tributylamine, pyridine, isoquinoline, etc. as an imidization catalyst. When the polyamic acid component (B) is produced at a low temperature, the composition of the present invention is non-uniform and some of the polymer is precipitated. However, by stirring at room temperature or raising the temperature after adding the imidization aid, a homogeneous and transparent solution can be obtained. If the temperature is raised too much, the viscosity will rise rapidly, so a temperature of 100°C or lower is usually preferred. The composition of the present invention can be used for moldings, coatings, adhesives, paints, as well as polyimide solutions and polyamic acid solutions.
Although it can be used for laminated products, it is a composition particularly suitable for producing polyimide films. By using this composition, there is no breakage of the film due to shrinkage during molding, and the resulting film has very good solvent resistance. The present invention will be explained in detail below with reference to Examples, but the present invention is not limited to the following Examples unless the gist of the invention is exceeded. The physical properties of the film were evaluated as follows. Tensile test: Measured at 20°C according to the test method of ASTMD638. Tear test: Measured at 20°C using a light load tear tester manufactured by Toyo Seiki Co., Ltd. Formability: Evaluated by the presence or absence of breakage during film production. 〇 indicates no breakage, and × indicates breakage. Solvent resistance: The film was bent to a radius of 0.7 mm and evaluated by the presence or absence of cracks when immersed in methyl ethyl ketone. 〇 means no crack occurs, ×
Yes, there is. Production example 1 Production of soluble polyimide (1) Into a four-necked flask (1) equipped with a thermometer, dropping funnel, and stirrer, add 3,3',4,4'-benzophenonetetracarboxylic dianhydride (hereinafter referred to as ,BTDA
(abbreviated as )) was accurately weighed and heated at 150° C. for 1 hour under vacuum. After cooling to room temperature, 259 ml of N-methyl-2-pyrrolidone was added and dissolved. The partially insoluble slurry was heated to 100℃ and tolylene diisocyanate (2,4-isomer 80%, 2,6-isomer 20%
%, hereinafter abbreviated as 80-TDI), 28.3g was added, and 100
The reaction was carried out at ℃ for 24 hours to obtain a 20% by weight homogeneous solution of polyimide. A portion of this polyimide solution was poured into water to precipitate a polymer, which was then vacuum dried at 100°C. The intrinsic viscosity of a 0.5 g/dl solution of this polymer in N-methyl-2-pyrrolidone was 0.44 dl/g. Production example 2 Production of soluble polyimide (2) Instead of 28.3g of 80-TDI, 22.7g of 80-TDI,
Same as Production Example 1 except that 8.2 g of 4,4'-diphenylmethane diisocyanate (hereinafter abbreviated as MDI) was used, and 80-TDI was added and reacted for 10 hours, and then MDI was added and reacted for 14 hours. A 20% by weight homogeneous transparent polyimide solution was obtained by this operation. The partially precipitated and dried polymer had an intrinsic viscosity of 0.48 dl/g. Production Example 3 Production of polyamic acid (1) In a 500ml four-necked flask equipped with a thermometer and a stirring device, add 4,4'-diaminodiphenyl ether (hereinafter referred to as
Weigh out 8.0g (abbreviated as ODA) accurately and add N-methyl-2-
84 ml of pyrrolidone was added and dissolved. This solution was cooled on ice, and 12.9 g of BTDA was added at once with vigorous stirring. Immediately after the addition, the temperature rose to 15°C. Stirring was continued for 2 hours while cooling with ice, and then stirring was continued for 2 hours at room temperature to carry out the reaction.
A weight percent solution was obtained. A part of this solution was diluted with N-methyl-2-pyrrolidone to prepare a 0.5 g/dl solution, and the intrinsic viscosity was measured and found to be 0.98 dl/g. Production Example 4 Production of polyamic acid (2) Polyamic acid was produced in the same manner as in Production Example 3, except that 4.0 g of ODA and 2.2 g of paraphenylenediamine (hereinafter abbreviated as PPD) were used instead of 8.0 g of ODA. A 20% by weight solution was obtained. The intrinsic viscosity of this polymer was 1.25 dl/g. Production Example 5 Production of polyamic acid (3) Polyamic acid was produced in the same manner as in Production Example 4, except that 4.0 g of 4,4'-diaminodiphenylmethane (hereinafter abbreviated as MDA) was used instead of 4.0 g of ODA.
A 20% by weight solution was obtained. The intrinsic viscosity of this polymer is
It was 1.03 dl/g. Example 1 50 g of the polyimide solution from Production Example 1, 21 g of the polyamic acid solution from Production Example 3, and 5 ml of acetic anhydride and 0.05 ml of pyridine were mixed. The mixture was heterogeneous, but became homogeneous and transparent after stirring for 3 hours at room temperature. A thin film of this uniform transparent solution was formed on a glass plate using a Gardner doctor knife, and heated at 120℃ for 10 minutes.
It was dried in a hot air drying oven for 1 minute. Next, this semi-dry film was fixed on a metal frame and further heated at 200℃ for 10 minutes.
Heating was performed at 350°C for 4 minutes to obtain a polyimide film with a thickness of 30 μm. Table 1 shows the physical properties of this film. Example 2 A polyimide film was obtained in exactly the same manner as in Example 1 using 50 g of the polyimide solution of Production Example 1 and 50 g of a polyamic acid solution having the same composition as Production Example 3 and an intrinsic viscosity of 1.02 dl/g. Table 1 shows the physical properties of this film. Examples 3, 4, 5 50 g of the polyimide solution of Production Example 2 and the polyamic acid solution of Production Example 3 (intrinsic viscosity 1.05 dl/
g) A polyimide film was obtained in the same manner as in Example 1 using 50 g (Example 3), 50 g of the polyamic acid solution of Production Example 4 (Example 4), and 50 g of the polyamic acid solution of Production Example 5 (Example 5). Ta. Table 1 shows the physical properties of this film. Reference Examples 1 and 2 Example 1 using the polyimide solutions of Production Examples 1 and 2
A polyimide film was obtained in the same manner as above. Table 1 shows the physical properties of this film. Reference Examples 3, 4, and 5 Same composition as Production Examples 3, 4, and 5, and respective intrinsic viscosities of 1.04 dl/g (Reference Example 3), 1.30 dl/g (Reference Example 4), and 1.06 dl/g (Reference Example) A polyimide film was obtained in the same manner as in Example 1 using the polyamic acid solution of 5). At this time, when drying at 200°C for 10 minutes, it was observed that about 2 out of 3 sheets were broken and detached from the metal frame, or the entire surface was torn. 【table】

Claims (1)

[Scope of Claims] 1 (A) 10 to 90 parts by weight of polyimide containing 3,3',4,4'-benzophenonetetracarboxylic dianhydride and tolylene diisocyanate as main reaction components (B) Aromatic 1. A polyimide composition comprising 10 to 90 parts by weight of an aromatic polyamic acid obtained by a reaction between a diamine and an aromatic tetracarboxylic dianhydride.