KR101692133B1 - Preparation method for polyimide products from polyimide water solution - Google Patents

Abstract

The present invention relates to a process for preparing a polyimide aqueous solution, comprising the steps of: a) preparing a polyimide aqueous solution by mixing polyimide, hydration reagent and water; And b) forming a polyimide molded article by using the polyimide aqueous solution. According to the above method, the economical efficiency is remarkably improved as compared with the conventional method of using an organic solvent in the production of a polyimide molded article It is possible to manufacture a polyimide product in an environmentally friendly manner.

Description

[0001] The present invention relates to a method for forming a polyimide solution using a polyimide aqueous solution,

The present invention relates to a polyimide molding method using a polyimide aqueous solution.

Recently, research and development of various high-tech materials are being carried out due to the growth of high-tech industries. As a result, new materials have been developed to overcome the disadvantages of polymer materials by exploiting existing advantages through research and development.

Especially, polyimide is one of the polymer materials that show superior properties compared to other polymers. It has excellent mechanical properties, high glass transition temperature, high thermal stability, and the like, , Liquid crystal alignment films, automobiles, precision instruments, packaging, medical materials, separators, fuel cells, secondary batteries, and the like.

Conventionally, when forming a polyimide for the production of such a polyimide molded product, the polyimide solution was dissolved in an organic solvent to prepare a polyimide solution, and then the polyimide solution was molded. In this process, an organic solvent was essentially used. Therefore, there is a problem that the organic solvent used must be discarded or recycled.

Korea Patent No. 92-002622

Disclosure of the Invention The present invention has been conceived in order to solve the above-mentioned problems, and it is an object of the present invention to provide a polyimide film, which can solve problems of disposal or recycling of an organic solvent, To provide a polyimide molding method using the aqueous solution.

According to an embodiment of the present invention, there is provided a method of manufacturing a polyimide solution, comprising: a) preparing a polyimide aqueous solution by mixing polyimide, water-baseing reagent, and water; And b) preparing a polyimide molded article from the polyimide aqueous solution.

In another embodiment of the present invention, a polyimide film is provided as a polyimide molded article produced according to the above method.

The polyimide molding method of the present invention can form polyimide without using an organic solvent, so that a polyimide molded article can be produced economically and environmentally friendly.

Brief Description of the Drawings Fig. 1 is a graph showing the effect of the FT (weight average molecular weight) of a polyimide film composed of 4,4'-oxydiphthalic anhydride and 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane according to Example 1 of the present invention -IR spectra.
2 shows the FT-IR spectrum of a polyimide film composed of a pyrotalic dianhydride and 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane according to Example 2 of the present invention.
FIG. 3 is a graph showing the results of a comparison between the cyclobutane-1,2,3,4-tetracarboxylic dianhydride and 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane according to Example 3 of the present invention FT-IR spectrum of the polyimide film.
4 is a graph showing the results of a comparison between the 1,2,4,5-cyclohexanetetracarboxylic dianhydride and 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane according to Example 4 of the present invention FT-IR spectrum of the polyimide film.
FIG. 5 is a graph showing the results of a comparison between the composition of 1,2,4,5-cyclohexanetetracarboxylic dianhydride and 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane according to Example 4 of the present invention The UV / vis spectrum of the polyimide film is shown.

The present invention relates to a process for preparing a polyimide aqueous solution, comprising the steps of: a) preparing a polyimide aqueous solution by mixing polyimide, hydration reagent and water; And b) preparing a polyimide molded article from the polyimide aqueous solution.

According to the above method, a polyimide molded article can be produced in an economical and environmentally friendly manner without using an organic solvent at the time of producing the polyimide molded article.

Hereinafter, the present invention will be described in more detail.

Production of molded polyimide

First, according to the present invention, a polyimide aqueous solution is prepared by mixing polyimide, water-hydrating reagent and water (step a).

The polyimide used is a synthetic polymer having an imide bond, and may be a pre-aliphatic, wholly aromatic or partially aliphatic polyimide, and the form of the polyimide is not particularly limited. In an exemplary embodiment, the polyimide of the present invention may be in powder form.

On the other hand, the polyimide used according to the present invention may have the structure of the following formula (1).

≪ Formula 1 >

(R ₁ in the formula 1 is a compound of the following

≪ / RTI >

In the above formula (1), R < _{2 &}

≪ / RTI > X is an integer satisfying 1? X? 50, n is a natural number in the range of 1 to 20, W, X and Y are each an alkyl or aryl group having 1 to 30 carbon atoms, and Z is an ester group , An amide group, an imide group and an ether group.

In the above formula (1), R ₃ is -OH, -COOH or -SO ₃ H.

A or b each represent an integer of 0 to 2, and a + b satisfies 1? A + b? 4.

On the other hand, the hydration reagent is not particularly limited as long as it serves to introduce a hydrophilic functional group into the polyimide so as to dissolve the polyimide in water.

In one embodiment of the present invention, the hydration reagent may be at least one compound selected from the group consisting of an amine compound, a metal hydroxide compound and a metal carbonate compound.

In one embodiment of the invention, the amine compound is trimethyl amine, triethyl amine, methyl-pyrrolidine, N, N - dimethyl-cyclohexyl amine, imidazole, 1,2-dimethyl-imidazole, N - methyl imidazole, N - benzyl-2-methylimidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 5-methyl benzimidazole, N - benzyl-2-methylimidazole , One selected from the group consisting of isoquinoline, 3,5-dimethylpyridine, 3,4-dimethylpyridine, 2,5-dimethylpyridine, 2,4-dimethylpyridine and 4-n- Or two or more amine compounds.

Meanwhile, in one embodiment of the present invention, the metal hydroxide compound may be a compound of the following formula (2).

M _x (OH) _y

(2)

Wherein M is selected from the group consisting of Li, Na, K, Mg and Ca, x is 1, y is 1 or 2,

Meanwhile, in one embodiment of the present invention, the metal carbonate compound may be a compound of the following formula (3).

M _a (CO ₃ ) _b

(3)

(Wherein M is selected from the group consisting of Li, Na, K, Mg and Ca, a is 1 or 2, and b is 1)

On the other hand, the water may be selected from the group consisting of distilled water, deionized water and tap water.

In one embodiment of the present invention, the polyimide included in the polyimide aqueous solution preparation in step a) may be added in an amount of 1 to 30 wt% based on the weight of the aqueous solution excluding the water-based reagent weight in the polyimide aqueous solution.

When the polyimide is added in an amount of less than 1 wt% based on the weight of the aqueous solution excluding the water-based reagent in the polyimide aqueous solution, the amount of the polyimide contained in the aqueous solution may be small and the desired mechanical and thermal characteristics may not be obtained. If it is added in an amount exceeding 30 wt%, there may be a problem that the polyimide added during the preparation of the aqueous solution is not completely dissolved.

Meanwhile, in one embodiment of the present invention, the hydration reagent included in the preparation of the polyimide aqueous solution may be added at a weight of 1 to 20 times the weight of the polyimide.

When the hydration reagent is added in an amount of less than 1 times the weight of the polyimide, there may be a problem that the polyimide is not dissolved well in the preparation of the aqueous solution of the polyimide, and there is a problem that the production cost increases when the amount exceeds 20 times .

According to an embodiment of the present invention, the step a) may be carried out at a temperature ranging from 5 to 40 ° C, more specifically, at a room temperature.

Meanwhile, the step a) may be conducted for 1 to 3 days. If the step progresses to less than one hour, there may be a problem that the polyimide is not completely dissolved. Economies can be a problem if it goes over three days.

Next, a polyimide molded article is obtained from the obtained polyimide aqueous solution to obtain a polyimide molded article (step b).

The molding step may be performed by at least one molding method selected from the group consisting of film forming, compression molding, injection molding, slush molding, blow molding, and extrusion molding. Particularly, As shown in FIG.

Meanwhile, the polyimide molded product manufactured according to the above-described series of methods may be a polyimide film, a high heat-resistant engineering plastic, an adhesive, a tape, a liquid crystal alignment film, an interlayer insulator, a coating film resin, a printed circuit board and a flexible display substrate.

According to the polyimide forming method described above, unlike the conventional polyimide forming method, since the polyimide is dissolved by using water instead of the organic solvent, the product is produced, which is economical and eco-friendly. The polyimide molded product manufactured according to the above method can be widely used for a next generation liquid crystal alignment film including a polyimide film, an insulating film for an organic thin film transistor, a plastic substrate for display, and a high dielectric material.

Particularly, the polyimide prepared according to the above method is widely used in a wide range of industries including space, aviation, electric / electronic, semiconductor, transparent / flexible display, liquid crystal alignment film, automobile, precision instrument, packaging, medical material, The value is high in the field.

Hereinafter, the present invention will be described in more detail with reference to Examples and Experimental Examples. It should be understood, however, that the following examples and experimental examples are provided to aid understanding of the present invention and are not intended to limit the scope of the present invention thereto.

Example

Example 1: Preparation of aqueous solution of wholly aromatic polyimide

N -methyl-2-pyrrolidone was added to a 100-mL 2-neck round bottom flask substituted with nitrogen gas, and 4,4'-oxydiphthalic anhydride (ODPA) and 2,2-bis -4-hydroxyphenyl) hexafluoropropane (6FAP) was added thereto, and the mixture was reacted at 25 ° C for 24 hours to synthesize a polyamic acid solution.

Next, pyridine and acetic anhydride were added to the polyamic acid solution and reacted at 160 ° C for 8 hours to synthesize polyimide.

Next, water was added to the reaction vessel, and 5 wt% of the wholly aromatic polyimide was added. Imidazole was added to the weight of the polyimide at 1 time, and the mixture was stirred at room temperature to prepare a wholly aromatic polyimide aqueous solution.

Next, the polyimide aqueous solution was spin-coated on the glass plate, and the temperature was gradually raised for 17 hours at the atmospheric pressure using a heater until the final temperature reached 300 占 폚, and maintained for 1 hour to produce a polyimide film (see Fig. 1 ).

Example 2: Preparation of aqueous solution of wholly aromatic polyimide

N -methyl-2-pyrrolidone was added to a 100-mL 2-necked round-bottomed flask substituted with nitrogen gas, and a mixture of pyrometallic dianhydride (PMDA) and 2,2-bis (3-amino- Hexafluoropropane (6FAP) was added thereto and reacted at 25 ° C for 24 hours to synthesize a polyamic acid solution.

Next, the polyamic acid solution was re-precipitated in distilled water, filtered and dried to obtain polyamic acid, which was reacted in an electric furnace at 300 ° C for 24 hours to synthesize polyimide.

Next, water was added to the reaction vessel, and the wholly aromatic polyimide was added in an amount of 10 wt%. Imidazole was added in an amount of 5 times the weight of the polyimide, and the mixture was stirred at room temperature to prepare a wholly aromatic polyimide aqueous solution.

Next, the polyimide aqueous solution was spin-coated on a glass plate, and the temperature was gradually raised for 17 hours at atmospheric pressure by using a heater until the final temperature reached 300 占 폚 and maintained for 1 hour to produce a polyimide film (see Fig. 2 ).

Example 3 Preparation of Aqueous Solution of Partial Aliphatic Polyimide

N -methyl-2-pyrrolidone was added to a 100-mL 2-necked round bottom flask substituted with nitrogen gas, and cyclobutane-1,2,3,4-tetracarboxylic dianhydride (CBDA) and 2,2- Bis (3-amino-4-hydroxyphenyl) hexafluoropropane (6FAP) was added thereto and reacted at 25 ° C for 24 hours to synthesize a polyamic acid solution.

Next, pyridine and acetic anhydride were added to the polyamic acid solution and reacted at 160 ° C for 8 hours to synthesize polyimide.

Next, water was added to the reaction vessel, the partial aliphatic polyimide was added in an amount of 10 wt%, 1,2-dimethylimidazole was added in an amount of 5 times the weight of the polyimide, and the mixture was stirred at room temperature to obtain an aqueous solution of a partially aromatic polyimide .

Next, the above polyimide aqueous solution was spin-coated on a glass plate, and the temperature was gradually raised for 17 hours at atmospheric pressure using a heater until the final temperature reached 300 DEG C, and maintained for 1 hour to produce a polyimide film (see FIG. 3 ).

Example 4 Preparation of Aqueous Solution of Partial Aliphatic Polyimide

N -methyl-2-pyrrolidone was added to a 100-mL 2-neck round bottom flask substituted with nitrogen gas, and 1,2,4,5-cyclohexanetetracarboxylic dianhydride (HPMDA) and 2,2- Bis (3-amino-4-hydroxyphenyl) hexafluoropropane (6FAP) was added thereto and reacted at 25 ° C for 24 hours to synthesize a polyamic acid solution.

Next, the polyamic acid solution was re-precipitated in distilled water, filtered and dried to obtain polyamic acid, which was reacted in an electric furnace at 300 ° C for 24 hours to synthesize polyimide.

Next, water was added to the reaction vessel, and 20% by weight of the partially aliphatic polyimide was added. Then, triethylamine was added 10 times to the weight of the polyimide, and the mixture was stirred at room temperature to prepare a partially aromatic polyimide aqueous solution.

Next, the polyimide aqueous solution was spin-coated on a glass plate, and the temperature was gradually raised for 1 hour by using a heater until the final temperature reached 300 캜 at the atmospheric pressure for 17 hours, thereby producing a polyimide film (FIGS. 4 5).

Comparative Example 1: Preparation of aqueous solution of wholly aromatic polyimide

N -methyl-2-pyrrolidone was added to a 100-mL 2-neck round bottom flask substituted with nitrogen gas, and 4,4'-oxydiphthalic anhydride (ODPA) and 4,4'-oxydianiline ODA) was added and reacted at 25 ° C for 24 hours to synthesize a polyamic acid solution.

Next, pyridine and acetic anhydride were added to the polyamic acid solution and reacted at 160 ° C for 8 hours to synthesize polyimide.

Next, water was added to the reaction vessel, and 10 wt% of the wholly aromatic polyimide was added. Imidazole was added 10 times with respect to the weight of the polyimide and stirred at room temperature, but the polyimide was not dissolved in water.

Comparative Example 2: Preparation of aqueous solution of partial aliphatic polyimide

N -methyl-2-pyrrolidone was added to a 100-mL 2-necked round-bottomed flask substituted with nitrogen gas and cyclobutane-1,2,3,4-tetracarboxylic dianhydride (CBDA) and 2,2 ' -Bis (trifluoromethyl) benzidine (TFMB) was added thereto and reacted at 25 ° C for 24 hours to synthesize a polyamic acid solution.

Next, the polyamic acid solution was re-precipitated in distilled water, filtered and dried to obtain polyamic acid, which was reacted in an electric furnace at 300 ° C for 24 hours to synthesize polyimide.

Next, water was added to the reaction vessel, and the partial aliphatic polyimide was added in an amount of 10 wt%. Then, 1,2-dimethylimidazole was added in an amount of 10 times the weight of the polyimide and stirred at room temperature. However, It was not dissolved.

Comparative Example 3: Preparation of aqueous solution of all aliphatic polyimide

N -methyl-2-pyrrolidone was added to a 100-mL 2-neck round bottom flask substituted with nitrogen gas, and 1,2,4,5-cyclohexanetetracarboxylic dianhydride (HPMDA) and 4,4 ' -Methylenebis (cyclohexylamine) (MCA) was added thereto and reacted at 25 ° C for 24 hours to synthesize a polyamic acid solution.

Next, the polyamic acid solution was re-precipitated in distilled water, filtered and dried to obtain polyamic acid, which was reacted in an electric furnace at 300 ° C for 24 hours to synthesize polyimide.

Next, water was added to the reaction vessel, and 10 wt% of the entire aliphatic polyimide was added. Triethylamine was added at 20 times the weight of the polyimide and stirred at room temperature, but the polyimide was not dissolved in water.

Comparative Example 4: Preparation of an aqueous solution of an all-poly-polyimide

N -methyl-2-pyrrolidone was added to a 100-mL 2-neck round bottom flask substituted with nitrogen gas, and 4,4'-oxydiphthalic anhydride (ODPA) and 2,2-bis -4-hydroxyphenyl) hexafluoropropane (6FAP) was added thereto, and the mixture was reacted at 25 ° C for 24 hours to synthesize a polyamic acid solution.

Next, the polyamic acid solution was re-precipitated in distilled water, filtered and dried to obtain polyamic acid, which was reacted in an electric furnace at 300 ° C for 24 hours to synthesize polyimide.

Next, water was added to the reaction vessel, and the partial aliphatic polyimide was added in an amount of 10 wt%. Imidazole was added in an amount of 0.1 times with respect to the weight of the polyimide and stirred at room temperature. However, the polyimide did not completely dissolve in water and remained .

As shown in Table 1, polyimide aqueous solution was prepared by adding hydrolysis reagent and water to the polyimide synthesized according to Examples 1 to 4, and then the solution was spin-coated on a glass plate, Lt; RTI ID = 0.0 > C, < / RTI > to obtain a polyimide film. It was confirmed that the polyimide film had similar mechanical properties and thermal properties as compared with a general polyimide film production method.

In particular, referring to FIG. 5, it was confirmed that the optical characteristics of the polyimide film obtained after dissolving the existing polyimide in water using a water-based reagent did not change significantly.

On the other hand, the polyimide synthesized in Comparative Examples 1 to 3 did not dissolve the polyimide even when the water-based reagent and water were added, and thus the polyimide aqueous solution could not be obtained. In Comparative Example 4, the polyimide solution had a structure suitable for the preparation of the polyimide solution. However, it was confirmed that the added polyimide did not completely dissolve and remained in water because the amount of the water-based reagent added was small.

Claims (13)

a) polyimide; A reagent selected from the group consisting of an amine compound, a metal hydroxide compound, and a metal carbonate compound; And water to prepare a polyimide aqueous solution; And
b) preparing a polyimide molded article with the polyimide aqueous solution,
From here,
The polyimide of step a) is a pre-aliphatic, wholly aromatic or partially aliphatic polyimide,
The polyimide of step a) is added in an amount of 1 to 30 wt% based on the weight of the aqueous solution excluding the weight of the reagent in the polyimide aqueous solution,
The reagent of step a) is added at a weight of 1 to 20 times the weight of the polyimide,
Wherein the step a) is carried out within a temperature range of 5 to 40 占 폚. delete delete delete The method according to claim 1,
The amine compound may be selected from the group consisting of trimethylamine, triethylamine, methylpyrrolidine, N, N -dimethylhexylamine, imidazole, 1,2-dimethylimidazole, N -methylimidazole, N- Methylimidazole, N -benzyl-2-methylimidazole, isoquinoline, 3,5-dimethylimidazole, Which is one or more amine compounds selected from the group consisting of dimethyl pyridine, 3,4-dimethylpyridine, 2,5-dimethylpyridine, 2,4-dimethylpyridine and 4-n- Mead molding method. The method according to claim 1,
Wherein the metal hydroxide compound is a compound represented by the following formula (2).
M _x (OH) _y
(2)
Wherein M is selected from the group consisting of Li, Na, K, Mg and Ca, x is 1, y is 1 or 2, The method according to claim 1,
Wherein the metal carbonate compound is a compound represented by the following formula (3).
M _a (CO ₃ ) _b
(3)
(Wherein M is selected from the group consisting of Li, Na, K, Mg and Ca, a is 2 or 1, and b is 1) delete delete delete The method according to claim 1,
Wherein the step a) is performed for 1 to 3 days. The method according to claim 1,
Wherein the step (b) is performed by at least one molding method selected from the group consisting of film forming, compression molding, injection molding, slush molding, blow molding, and extrusion molding. delete

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