JPH07119280B2 - New method for producing polyamide-imide - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a method for producing a novel polyamideimide excellent in solubility and moldability.

[Conventional technology]

Although the heat resistance of the polyimide resin is excellent, many of them are insoluble and infusible, so that the moldability is poor. for that reason,
For forming into a film or the like, a varnish dissolved in an organic solvent in the state of polyamic acid as a precursor was used. However, since the molecular weight of polyamic acid varnish is likely to decrease due to hydrolysis, it had to be stored at low temperature.
In addition, it is unavoidable to use a solvent that easily absorbs moisture,
Therefore, there is a problem that the resin is deposited from the varnish due to moisture absorption. Further, there is a problem that voids remain in the molded product because condensed water is generated during imidization after molding into a film or the like.

In addition, there is a problem in that it cannot be used for a heat-sensitive substrate because it is necessary to raise the temperature to 300 ° C. or higher when imidizing.

In order to solve this problem, a polyimide having a softening point and capable of being molded has been developed.

For example, JP-A-62-10051 discloses that a compound represented by the general formula (A) Although a polyimide composed of a diamine represented by the formula (wherein X is CO or SO ₂ ) and pyromellitic acid is disclosed, this polyimide has a softening point and can be molded.

Further, in order to solve the above-mentioned problems, a polyamideimide soluble in an organic solvent has been developed. For example, Japanese Patent Publication Sho 44
No. -19274 discloses a polyamideimide obtained from tribasic acid anhydride and diisocyanate, which is soluble in aprotic polar solvents such as dimethylacetamide (DMAc) and dimethylformamide (RMF).

[Problems to be Solved by the Invention]

The polyimide disclosed in JP-A-62-10051 has a softening point and can be molded, but the softening point is too high,
Must be molded at temperatures above 300 ° C. Also,
Since the polyimide is poorly soluble in an organic solvent, it must be formed into a film using a varnish prepared by dissolving a polyamic acid which is a precursor thereof in an organic solvent in order to form a film, and the film must be heated to a high temperature to be imidized. However, there are problems as described above.

The polyamide-imide disclosed in JP-B-44-19274 has a too high softening point, so that it needs to be molded at a temperature of more than 300 ° C. Further, although they are soluble in DMAc, DMF and the like, these solvents have high boiling points and it is difficult to remove the solvents. Therefore, development of a polyamide-imide which is soluble in a solvent having a lower boiling point is desired.

[Means for Solving the Problems]

The present invention relates to trimellitic acid or its derivative and the general formula (I) (In the formula, X represents C═O or SO ₂ , and Y represents —NH ₂ or —NCO). The present invention relates to a method for producing a polyamide-imide.

Examples of the trimellitic acid derivative include trimellitic anhydride, trimellitic anhydride monochloride, trimellitic anhydride monohalide such as trimellitic anhydride fluoride, 4-methoxycarbonylphthalic anhydride, trimellitic anhydride such as 4-ethoxycarbonylphthalic anhydride. Acid monoester, 4-methoxycarbonylphthalic acid, 4-
Ethoxycarbonylphthalic acid, methyl 2,5-dicarboxybenzoate, ethyl 2,5-dicarboxybenzoate, 2,4-
Examples include trimellitic acid monoesters such as methyl dicarboxybenzoate and ethyl 2,4-dicarboxybenzoate, and trimellitic acid diesters such as dimethyl 4-carboxyphthalate and diethyl 4-carboxyphthalate.

In the present invention, the partner of the reaction of trimellitic acid or its derivative contains the compound represented by the general formula (I) as an essential component.

The compound represented by the general formula (I) is preferably a compound represented by the general formula (I) in which an amino group and oxygen are bonded to the para-position or the meta-position with respect to the isopropylidene group,
Furthermore, it is desirable that at least one of the two amino groups and the two oxygens be in the meta position with respect to the soypropylidene group.

In the general formula (I), as the ratio of the meta position in the bonding positions of the amino group and oxygen to the isopropylidene group increases, the softening point of the obtained polyimide becomes lower and the solubility in an organic solvent becomes better, but the softening occurs. If the points become too low, the strength of the polyimide molded article at high temperature tends to decrease, so it is preferable to determine the ratio of the meta position according to the purpose. From this point of view, the compound represented by the general formula (I) is a compound represented by the general formula (I) in which the group Y is bound to the para position and the oxygen is bonded to the meta position with respect to the isopropylidene group, that is, , General formula (II) A compound represented by the formula (wherein X and Y are the same as those in the general formula (I)) is particularly preferable.

The compound represented by the general formula (I) is preferably 50 mol% as a partner of the reaction of trimellitic acid or its derivative.
Above, particularly preferably 75 mol% or more is used. If the amount of the compound represented by the general formula (I) is too small, the obtained polyamide-imide tends to have a high softening point, and also tends to be hardly soluble in an organic solvent.

Among the compounds represented by the general formula (I), as the diamine in which the group Y is an amino group, 4,4′-bis [3- (4-amino-α, α′-dimethylbenzyl) phenoxy] diphenyl sulfone, 4,4'-bis [3- (4-amino-
α, α′-dimethylbenzyl) phenoxy] benzophenone, 4,4′-bis [4- (4-amino-α, α′-dimethylbenzyl) phenoxy] diphenyl sulfone, 4,
4'-bis [4- (4-amino) -α, α'-dimethylbenzyl) phenoxy] benzophenone, 4- [3-
(4-Amino-α, α'-dimethylbenzyl) phenoxy] -4 '-[4- (4-amino-α, α'-ditylbenzyl) phenoxy] diphenylsulfone, 4- [3
-(4-Amino-α, α'-dimethylbenzyl) phenoxy] -4 '-[4-amino-α, α'-dimethylbenzyl) phenoxy] benzophenone, 4,4'-bis [3
-(3-Amino-α, α'-dimethylbenzyl) phenoxy] diphenyl sulfone, 4,4'-bis [3- (3-
Amino-α, α'-dimethylbenzyl) phenoxy] benzophenone, 4,4'-bis [2- (4-amino-α,
α'-Dimethylbenzyl) phenoxy] diphenyl sulfone, 4,4'-bis [2- (4-amino-α, α'-dimethylbenzyl) phenoxy] benzophenone, 3,3 '
-Bis [3- (4-amino-α, α'-dimethylbenzyl) phenoxy] diphenyl sulfone, 3,3'-bis [3- (4-amino-α, α'-dimethylbenzyl) phenoxy] benzophenone, etc. And these may be mixed and used.

When the compound represented by the general formula (I) is a diamine, other diamines which may be used together as a reaction partner of trimellitic acid or its derivative include diaminodiphenylmethane, diaminodiphenyl ether, diaminodiphenyl sulfone. , Diaminodiphenyl ketone, diaminodiphenylpropane, phenylenediamine, toluenediamine, bis (anilinoisopropylidene) benzene, bis (aminophenoxy) benzene, diaminodiphenyl sulfide, bis (aminophenoxyphenyl)
There are propane, bis (aminophenoxyphenyl) sulfone, bis (aminophenoxyphenyl) ketone, bis (aminophenoxyphenyl) hexafluoropropane, diaminodiphenylhexafluoropropane, diaminodialkylcyclophenylmethane, etc., Two or more of these may be used in combination.

Among the compounds represented by the general formula (I), as the diisocyanate in which the group Y is an isocyanate group, 4,4′-
Bis [3- (4-isocyanato-α, α'-dimethylbenzyl) phenoxy] diphenyl ketone, 4,4'-bis [3- (4-isocyanato-α, α'-dimethylbenzyl) phenoxy] diphenyl sulfone In addition, among the compounds represented by the general formula (I), there is a diamine in which the group Y is an amino group, in which the amino group is replaced with an isocyanate group. Examples of the diisocyanate that may be used include diphenyl methane diisocyanate, toluylene diisocyanate, and the like, in which the amino group of the other diamine described above is replaced with an isocyanate.

In the present invention, the polyamide-imide can be manufactured as follows.

When a diamine is used as a reaction partner of trimellitic acid or a derivative thereof (particularly other than trimellitic anhydride monohalide), these are used in an organic solvent, if necessary, as a catalyst for tributylamine, triethylamine, triphenyl phosphite, etc. In the presence of 100 ℃ or more, preferably 180
A method for directly obtaining a polyamide-imide by heating to ℃ or more and performing imidization (catalyst is preferably used in an amount of 0 to 15% by weight based on the total amount of reaction components, particularly 0.01 to
It is preferable to use 15% by weight), and particularly when diamine is used as a trimellitic acid derivative as a reaction partner of trimellitic anhydride monohalide, these are reacted in an organic solvent at a temperature of less than 100 ° C. to prepare a polyamideimide precursor. When the varnish of polyamic acid is prepared, the varnish is then heated to imidize it, or an acid anhydride such as acetic anhydride, propionic anhydride, or benzoic anhydride, or a ring-closing ring such as carbodiimide such as dicyclohexylcarbodiimide. Agent and, if necessary, a ring-closing catalyst such as pyridine, isoquinoline, trimethylamine, aminopyridine, imidazole, etc. for chemical ring-closing (imidization) (ring-closing agent and ring-closing catalyst are each added to 1 mol of trimellitic acid halide compound). On the other hand, it is preferably used in the range of 1 to 8 mol).

The organic solvent that can be used in the present invention is N
-Methyl-pyrrolidone, N, N-dimethylacetamide,
N, N-dimethylformamide, dimethyl sulfoxide,
Examples include aprotic polar solvents such as sulfolane, hexamethylphosphoric triamide, and 1,3-dimethyl-2-imidazolidone, and phenol-based solvents such as phenol, cresol, xylenol, and p-chlorophenol.

Benzene, toluene, xylene, methyl ethyl ketone, acetone, tetrahydrofuran, dioxane, monoglyme, diglyme, methyl cellosolve,
Solvents such as cellosolve acetate, methanol, ethanol, isopropanol, methylene chloride, chloroform, trichlene, and tetrachloroethane can be mixed and used within a range that does not impair the solubility of polyimide or polyamic acid.

When diisocyanate is used as a partner of the reaction of trimellitic acid or its derivative, it can be carried out according to the above-mentioned method for directly obtaining polyamideimide. However, it is sufficient that the reaction temperature is room temperature or higher, particularly 60 ° C. or higher.

In the present invention, trimellitic acid or its derivative and its reaction partner are preferably used in approximately equimolar amounts, but an excess of either one is allowed to be 10 mol%, particularly preferably up to 5 mol%.

The polyamide imide obtained in the present invention is soluble in aprotic polar solvents such as DMF, dioxane, ether solvents such as tetrahydrofuran, halogenated hydrocarbons such as methylene chloride, and should be molded into a film or the like from these solutions. You can The softening point can be easily adjusted to 100 to 250 ° C.

The polyamide-imide obtained in the present invention can be used as a molded product, an adhesive, a structural material or the like. Further, the polyamide-imide obtained in the present invention can be appropriately produced from its precursor and used.

The diamine in which the group Y of the compound represented by the general formula (I) is an amino group is 4,4′-difluorobenzophenone or 4,4 ′ with respect to 2 mol of the corresponding hydroxyphenylaminophenylpropane. It can be produced by heating 1 mol of dichlorodiphenyl sulfone to 100 ° C. or higher in a polar organic solvent in the presence of a base such as potassium hydroxide or anhydrous potassium carbonate.

Further, the diisocyanate in which the group Y of the compound represented by the general formula (I) is an isocyanate group can be produced by reacting the diamine thus obtained with phosgene according to a conventional method. it can.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to these ranges.

Production Example 1 In a four-necked flask equipped with a cooling pipe thermometer and a stirrer nitrogen gas introduction pipe, 2- (3-hydroxyphenyl) -2-
45.4 g of (4'-aminophenyl) propane, 100 ml of dimethyl sulfoxide and 120 ml of chlorobenzene were added and dissolved at room temperature, and then an aqueous solution of 13 g of potassium hydroxide dissolved in the same amount of water was added. The mixture was heated and stirred while flowing nitrogen gas to distill water. After the water had stopped distilling, the temperature was lowered to 100 ° C, 21.8 g of 4,4'-difluorobenzophenone was added, and 16
The reaction was carried out at 5 ° C for 4 hours. After cooling to room temperature and filtering out the precipitate, it was poured into water to obtain a crude product. The crude product was recrystallized from a toluene-hexane mixed solvent to obtain the target compound 4,4'-bis [3- (4-amino-α, α'-dimethylbenzyl) phenoxy] diphenyl ketone. Yield 45.5g, melting point 107-110 ° C Liquid chromatography (column: Tosoh Corp. TSK Gel G2000H and G3000H are connected,
The purity was 99.0% (area ratio) with the eluent tetrahydrofuran).

The analysis result of this diamine is as follows.

(1) Elemental analysis value (%) C ₄₃ H ₄₀ N ₂ O ₃ C HN Calculated value 81.65 6.33 4.43 Measured value 81.57 6.41 4.32 (2) Infrared absorption spectrum (IR) absorption position (KBr tablet method, cm ^-1 ). 3460,3390 (amino group) 2970,2870 (methyl group) 1600 (carbonyl group) 1250 (ether group) (3) Spectral position of nuclear magnetic resonance spectrum (NMR) (DMSO-d ₆ , ppm) 1.57 (12H singlet ) 4.86 (4H singlet) 6.4 to 7.8 (24H multiplet) Note) DMSO means dimethyl sulfoxide.

Production Example 2 In a four-necked flask equipped with a cooling pipe thermometer, a stirrer, and a nitrogen gas introduction pipe, 2- (3-hydroxyphenyl) -2-
(4'-Aminophenyl) propane 68.1 g, dimethyl sulfoxide 150 ml, chlorobenzene 180 ml, 4,4'-dichlorodiphenyl sulfone 40.75 g, anhydrous potassium carbonate 20.5
After charging g, the mixture was heated and stirred under aeration of nitrogen gas to distill water. After reacting at 165 ° C. for 4 hours, it was cooled to room temperature.
The reaction solution was poured into water to obtain a crude product. Recrystallization from a benzene-hexane mixed solvent gave 71.1 g of the desired compound 4,4'-bis [3- (4-amino-α, α'-dimethylbenzyl) phenoxy] diphenylsulfone. Melting point 67-7
The purity by liquid chromatography at 0 ° C was 99.4%.

The analysis result of this diamine is as follows.

(1) Elemental analysis value (%) C ₄₂ H ₄₀ N ₂ O ₄ S C HNS Calculated value 75.45 5.99 4.19 4.79 Measured value 75.18 6.03 4.02 4.66 (2) Absorption position of (IR) (KBr tablet method, cm ^-1 ). 3450,3390 (amino group) 2970,2870 (methyl group) 1290,1110 (sulfonyl group) 1250 (ether group) (3) NMR spectrum position (DMSO-d ₆ , ppm) 1.55 (12H singlet) 4.87 (4H Single line) 6.4 to 8.0 (24H multiple line) Example 1 4,4'-bis [prepared in Production Example 1 in a four-necked flask equipped with a stirrer, a thermometer, a nitrogen gas inlet tube, and a downward cooling tube] 3- (4-Amino-α, α'-dimethylbenzyl) phenoxy] benzophenone 3.16 g and trimellitic anhydride
0.96 g, 15 ml of N-methylpyrrolidone and 0.2 g of triphenyl phosphite were added and reacted at 200 ° C. for 5 hours while flowing a nitrogen gas to obtain a polyamideimide varnish. This varnish was poured into water, reprecipitated, pulverized and dried to obtain polyamideimide powder. The reduced viscosity measured in the same manner as in Example 1 is
It had a softening point of 158 ° C, a 5% weight loss temperature of 480 ° C, and was soluble in DMF, NMP, dioxane, tetrahydrofuran, and monoglyme.

Example 2 4,4′-bis [3- (4-amino-α, α ′) obtained in Production Example 2 was placed in a four-necked flask equipped with a stirrer, a thermometer, a calcium chloride tube, and a nitrogen gas introducing tube. -Dimethylbenzyl)
3.34 g of phenoxy] diphenyl sulfone, 0.51 g of triethylamine and 20 ml of N, N'-dimethylacetamide DMAc are added and dissolved. 1.1 g of trimellitic anhydride monochloride was added little by little while cooling to 0 ° C. or lower, and then the mixture was reacted at 5 ° C. or lower for 3 hours and at room temperature for 1 hour to obtain a polyamic acid varnish which is a precursor of polyamideimide. To this varnish, 1.3 g of acetic anhydride and 1.0 g of pyridine were added and reacted at room temperature for 3 hours to obtain a polyamideimide varnish. This varnish was poured into water, reprecipitated, pulverized and dried to obtain polyamideimide powder. The reduced viscosity was 0.35 dl / g in DMF at a concentration of 0.1 g / dl and a temperature of 30 ° C, and the softening point was 172 ° C as measured by a Koka type flow tester under a load of 10 kg / cm ² .

〔The invention's effect〕

According to the present invention, it is a low softening point as is clear in Examples,
Polyamideimide having excellent solubility can be produced.

Claims (5)

[Claims] 1. A trimellitic acid or its derivative and a general formula (I). (However, in the formula, X represents C = O at or SO _2, Y represents an -NH ₂ or -NCO) preparation of polyamide-imide which comprises reacting a compound represented by. 2. The compound represented by the general formula (I) is a compound represented by the general formula (I) in which the group Y and oxygen are bonded to the para-position or the meta-position with respect to the isopropylidene group. Item 2. A method for producing a polyamide-imide according to Item 1. 3. The compound represented by the general formula (I) is the compound according to claim 2, and in the general formula (I), 2
The method for producing a polyamide-imide according to claim 2, wherein at least one of the group Y and the two oxygens is bonded to the isopropylidene group in the meta position. 4. The compound represented by the general formula (I) is the compound according to claim 3, and the group Y is para to the isopropylidene group in the general formula (I). The method for producing a polyamide-imide according to claim 3, wherein oxygen is bound to the meta position. 5. The method for producing a polyamide-imide according to claim 1, 2, 3 or 4, wherein the group Y in the general formula (I) is an amino group.