JPH02117957A - Polyamide-imade resin composition - Google Patents

Abstract

PURPOSE:To obtain the title composition outstanding in mechanical strength, melt fluidity and economy and suitable as a thermoplastic molding material by incorporating a polyamide-imide resin with an antioxidant. CONSTITUTION:The objective composition can be obtained by incorporating (A) a polyamide-imide resin pref. >=0.4dl/g in intrinsic viscosity, prepared by reaction in a polar solvent (pref. N-methylpyrrolidone) between A1: trimellitic anhydride (derivative) and A2: an aromatic diamine (pref. 4,4'- diaminodiphenylmethane) or aromatic diisocyanate (4,4'-diphenylmethane diisocyanate), and, if needed, furthermore, A3: a dicarboxylic acid (pref. isophthalic acid) and/or lactam (pref. epsilon-caprolactam) with (B) 1-40 (pref. 5-20) wt.% of an antioxidant (pref. phenolic antioxidant >=200 deg.C in melting point).

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to polyamideimide resin compositions.

More specifically, the present invention relates to a polyamide-imide resin composition having excellent mechanical strength, melt fluidity, and economical efficiency.

(Prior Art) Conventionally, the following two methods are known as methods for producing inexpensive polyamide-imide resins.

(1) Incyanate method: For example, a method in which trimellitic anhydride is reacted with diphenylmethane-4,47-diisocyanate (for example, Japanese Patent Publication No. 44-19274, Publication No. 44719/1989, 1% -70
Publication No. 452, 4! Publication No. 57-125220).

(2) Amine method: For example, a method in which trimellitic anhydride and aromatic diamine are reacted (for example,
-4077, 9%, 1984-14622, JP-A-52-104596).

However, depending on the polyamide-imide resin obtained by these methods, 9 they undergo significant oxidative deterioration during molding at high temperatures in an air atmosphere, which is the usual molding condition, and only molded products with weak mechanical strength can be obtained.

This resin also had insufficient melt fluidity, making it difficult to put it into practical use.

(Problem to be solved by the invention) The object of the present invention is to eliminate the drawbacks of the prior art.

An object of the present invention is to provide a polyamide-imide resin composition having excellent mechanical strength, melt fluidity, and economical efficiency.

(l! Means for Solving the Problem) The present invention provides trimellitic anhydride or its derivatives (l!
) and aromatic diamine ([I) and aromatic diisocyanate (■), if necessary further dicarboxylic acid CIt
/) and/or lactam (Vl) in a polar solvent.
) is added to a polyamideimide resin composition.

As trimellitic anhydride or its derivative (1) used in the present invention, trimellitic anhydride is preferably used, and as the trimellitic anhydride derivative,
Esterified products of trimellitic acid or trimellitic anhydride and alcohol, etc.

For example, a methanol half ester of trimellitic anhydride may be used.

As the aromatic diamine (II) used in the present invention.

Examples, t ha m-phenylenediamine/l p-phenylenediamine, 4,4'-diaminodiphenylpropane.

4.4'-diaminodiphenylmethane, 4.4'-diaminodiphenyl sulfide, 4.4'-diaminodiphenylsulfone, 4.4'-diaminodiphenyl ether, 1.5-diaminonaphthalene, 3.3'-diaminodiphenyl, turtle 3'-dimethoxybenzidine, 1,3-diamino-4-isopropylbenzene, xylylphurfudiamine. 4. /-diaminoterphenyl, 4°4'
-diaminoquaterphenyl, 1,4-bis(p-aminophenoxy)penzea, 4.4'-Cbis-(p-
aminophenoxy)] diphenylsulfone, 4.4'-
[bis-(p-aminophexy)]biphenyl, λ2-
Bis(4-(4-aminophenoxy)phenyl)propane, 42-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 4,4'-diaminobenzophenone.

Benzidine-2,3,5,6-titramethyl-p-phenyle/diamine, diaminotoluene, tetrafluorophenylendiamine, diaminooctafluorobiphenyl, 4,4'-methylenebis(2,6-dime+/L, 7:
IJn), 4.4'-methylenebis(λ6-dinitylaniline), 4.4'-methylenebis(2,6-dipropylaniline), 4.4'-methylenebis(2-methyl-6-ditylaniline) etc.

Among these compounds, especially considering economic efficiency and the effect of adding antioxidants, compounds having a group that is easily oxidized in one molecule, such as an alkyl group, an alkylene group, or an alkylene group, specifically, 4.4' -diaminodiphenylmethane,
4.4'-methylenebis(λ6-dimethylaniline),
4.4'-methylenebis-(46-dinithylaniline)
Methylenebisaniline with an alkyl group added, such as 2.
Preference is given to using 2-bis[4-(4-aminophenoxy)phenyl]propane.

As the aromatic diisocyanate, for example, an aromatic diincyanate obtained by reacting the above diamine with phosgene or thionyl chloride is used. Considering economic efficiency and the effect of antioxidants, groups that are easily oxidized in the molecule, such as alkyl groups.

Compounds having an alkylene group or an alkylidene group, specifically 4,4'-diphenylmethane diisocyanate), 4.
Methylenebisphenylisocyanate with an alkyl group such as 4'-methylenebis(λ6-simethylphenyl isocyanate), 4.4'-methylenebis(slow-diethylphenylisocyanate), 2.2-bis[4-
Preferably, (4-incyanatophenoxy)phenyl]propane is used.

In the method of the present invention, if desired, trimellitic anhydride or its derivative +1) and aromatic diamine (II
) or aromatic diisocyanates (in addition to DIIK).

Dicarboxylic acids (IV) and/or lactams (V) are used; examples of dicarboxylic acids (N) used as needed in the present invention include succinic acid, adipic acid,
Examples include sebacic acid, dodecanedicarboxylic acid, isophthalic acid, and terephthalic acid. Among these compounds, inophthalic acid is preferably used in consideration of heat resistance and solubility of the resin.

The lactams used as necessary in the present invention are of the general formula.

A lactam of HN-□CO\/(Cth)n (in the formula, n represents an integer of 2 to 20) is used, and preferably ε-caprolactam is used.

In the method of the present invention, it is possible to use two components, dicarboxylic acid (IV) and lactam (■), in a specific ratio as necessary. A high degree of melt fluidity is obtained.

Dicarboxylic acids (The mixing ratio between them is determined from the viewpoint of melt fluidity and heat resistance.

(molar ratio) (m is trimellitic anhydride or a derivative thereof) is preferable, and especially KO, 08 to 0.15 (molar ratio) is preferable.

The mixing ratio of lactam (Vl) is preferably 1% KO (molar ratio) from the viewpoint of melt fluidity and heat resistance, and preferably 10 to 0.18 (molar ratio).

Furthermore, in the method of the present invention, an acid component ((RIJUKON)) and an amine component (Ill, t) or an isocyanate component (I
II) is preferably used so that the ratio of (Ill(It/)K to ([[l or full) is approximately equimolar, and particularly K (molar ratio) is preferable.

The polar solvent used in the present invention is preferably one that dissolves the resulting polyamide-imide resin well and has a boiling point of 180°C or higher.9 For example, N-butylpyrrolidone, N-ethylpyrrolidone, N-butylpyrrolidone, phenol, cresol , xylenol usulfolane γ
-butyl lactone, etc. Among these compounds, it is preferable to use N-methylpyrrolide/.

In the present invention, when synthesizing polyamideimide resin using aromatic diamine, it is preferable to add a dehydration catalyst. As a dehydration catalyst.

For example, trivalent or pentavalent organic or inorganic phosphorus compounds,
- Lead oxide, boric acid, boric anhydride. Among these compounds, it is preferable to use phosphoric acid, triphenyl phosphate, boric acid or boric anhydride.

The ratio of the dehydration catalyst used is O to the acid component 1-+v)).
, preferably 1 to 10% by weight, and preferably 1 to 5% by weight.

When synthesizing the polyamide-imide resin of the present invention using an aromatic diamine, firstly, the 7-mer is uniformly mixed and dissolved, the temperature is raised to 170°C, and the temperature is further raised while dehydrating to carry out a polymerization reaction at 205°C. It is preferable.

At this time, it is preferable to proceed with the polymerization reaction while distilling by-product water from the reaction system, and if necessary, a small amount of toluene,
190-220℃ in the presence of a dehydration accelerator such as xylene
It is preferable to carry out the polymerization reaction nearby.

The polymerization concentration may be about 40 to 5011% in the early stage of the reaction, and in the late stage of the reaction, it is preferable to increase the concentration to around 65% by weight in order to maintain a high @. After the polymerization reaction is completed, the terminal groups can be blocked with an end group blocking agent. By capping the terminal groups, thermal stability during molding is improved.

Examples of end group blocking agents used in this case include phthalic anhydride, benzoic acid, acetic anhydride, and aniline.

Examples include n-butylamine and phenyl isocyanate.

Reduced viscosity of polyamideimide resin obtained by the present invention (solvent dimethylformamide, sample concentration: 0.59/
d/measured at a temperature of 30°C) is 0.40 in terms of mechanical strength.
(a//g) or more is preferred.

Examples of the antioxidant (M) in the present invention include hydroquinone, hydroquino/monomethyl ether,
Di-t-butylhydroquinone, 2.5-1-amylhydroquinone, t-butylcatechol, styrenated phenol, 2-1-butyl-4-methylphenol, 2.
6-di-t-butylphenol, polybutylated bisphenol A.

4.4'-dihydroxydiphenylsulfone (bisphenol S), bisphenol A, thiobisphenol,
2,4.5-)lyhydroxybutyrophenone.

2.6-di-1-butyl-4methylphenol, 4゜6
-di-t-butyl-2-methylphenol, butylhydroxyanisole, 2,2'-methylenebis(4-methyl-6-t-butylphenol), 4°4'-methylenebis(26-di-t-butylphenol), tris( 2
-methyl-4-hydroxy-5-t-butylphenol)butane, 1. &5-) Liethyl-2.4.6-tris(3,5-di-t-butyl-4-hydroxybenzyl)
Benzene, tetrakis [methylene-(3/, 5/-di-t-butyl-4-hydroxyhydrocinnamate)]
meta/, 1°λ5-tris(4-1-butyl-3-hydroxy-slodimethylbenzyl)isocyanurate.

1,&5-tris(&5-di-t-butyl-4-hydroxybenzyl)isocyanurate, I RGANOX
245, IRGANOX259. IRGANOX565
゜IRGANOXIOIO, IRGANOX1035゜El GANOX1076, IRGANOX1081゜I
RGANOX1098. IRGANOX1222゜ELGANOXI 330. IR, GANOXI 425W
Phenolic antioxidants such as L (manufactured by Ciba Geigy, trade name), dilauryl thiodiglovironate, simyristyl thiodipropionate, distearyl thiodiglopionate, lauryl stearyl thiodipropionate, pentaerythritol -tetrakis(3-laurylthiopropionate), 4,4'-thiobis(3-methyl-6-1-butylphenol), 2-2'-thiobis(4-methyl-6-t-butylphenol), bis(
3-methyl-4-hydroxy-5-t-butylbenzyl) sulfide, sulfur-based antioxidants such as 2-mercaptobenzimidazole, triphenyl phosphite, triotadecyl phosphite, tridecyl phosphite,
Phosphorous antioxidants such as trilauryltrithiophosphite I N-n-butyl-p-aminephenol, octylated diphenylamine, N,N'-diimpropyl-p-phelenediamine, N,N'-di5ec-
Butyl-p-7enylenediamine, N,N'-bis(1,4-dimethylpentyl)-1)-phenylenecyamine, N,N'-bis(1-ethyl-3-methylpentyl)-p- Phenyl diamine, N-phenyl-N/
-Improvir-p-phenylenediamine, N, N
'-diphenyl-p-diphenylenediamine, N, N'
- Amine-based antioxidants such as β-naphthyl-p-phinidine diamine, phenothiazine, and N-phenyl-α-naphthylamine are used, and the melting point of the antioxidant is 2.
Phenolic antioxidants having a temperature of 00°C or higher are preferred.

In particular, it is preferable that 4,4'-dihydroxydiphenylsulfone (bisphenol s > .

If the amount of antioxidant added is less than 1 weight, the antioxidant effect during heating will be insufficient, and '! There is a tendency for melt fluidity to decrease. If the amount exceeds 40% by weight, oxidation during heating and melt fluidity will be significantly improved, but the heat resistance and mechanical strength as a molding material will tend to decrease, so the ability to provide oxidation prevention ability and melt fluidity will decrease. The amount of antioxidant to be added may be determined by taking these into consideration. The antioxidant is added to the resin composition after 9 synthesis or to the powdered resin from which the solvent has been removed, but it is particularly preferable to add it to the powdered resin.

One preferred embodiment of the present invention is to use 4'-diaminodiphenylmethane as the aromatic diamine or 4,47-cyphenylmethane diisocyanate as the aromatic diisocyanate to add phenol having a melting point of 200°C or higher to the polyamide-imide resin. 4. As a system antioxidant.
This is a polyamide-imide resin composition in which 1 to 40% by weight of 47-dihydroxydiphenyl sulfone is added to the polyamide-imide resin.

This composition has excellent economic efficiency because it can be obtained using general-purpose materials. Also, 4,4'-diaminodiphenylmethane, 4
The addition of 4°4'-dihydroxydiphenylsulfone suppresses oxidative deterioration of the easily oxidized methylene bonds in 4'-diphenylmethane diisocyanate, resulting in excellent mechanical strength. Low molecular weight 4.4' with even higher melting point
- By adding a large amount of dihydroxydiphenyl sulfone, the balance between melt fluidity and heat resistance is excellent.

A polyamide-imide resin set obtained by the present invention.

The parabolic material may contain different polymers, additives, and fillers if desired.

A reinforcing agent or the like may also be added.

The polyamide-imide resin composition obtained by the present invention is
If necessary, the physical properties can be significantly improved by heat treatment (at a temperature lower than the glass transition temperature for 1 to 24 hours) after molding.

(Effects of the Invention) According to the present invention, a polyamide-imide resin composition having excellent heat resistance, melt fluidity, and economic efficiency can be obtained.

The polyamide-imide resin composition obtained by the present invention is
It is suitable as a thermoplastic molding material.

For example, it is useful as a heat-resistant material such as a heat-resistant paint, a heat-resistant sheet, a heat-resistant contact agent, a heat-resistant laminated material, a heat-resistant sliding material, a heat-resistant fiber, and a heat-resistant film.

(Example) The present invention will be explained below with reference to examples.

Example 1 The above components were placed in a four-loaf flask equipped with a stirrer, a nitrogen inlet tube, and a moisture meter, and the temperature was gradually raised to 205° C. while introducing nitrogen gas while stirring.

Water distilled out at the same temperature is quickly removed from the reaction system.

At the same time, the reaction was carried out at 205 to 210°C while additionally replenishing distilled N-methylpyrrolidone.

The end point of the reaction was controlled by high-performance fluid chromatography, and the reduced viscosity (dimethylformamide, 0.5 g/dl!

A polyamide-imide resin of 10.49 (dJ/s) was obtained at 30°C.

The obtained polyamideimide resin solution was diluted with N-methylpyrrolidone to a concentration of about 25% by weight/C.

This solution was dropped into water that was vigorously stirred with a mixer, and a solid polyamide-imide resin was recovered. After thoroughly washing this solid resin with hot water, it was boiled and washed with a large amount of water. After filtering this, it is dried in a hot air dryer at 160°C for 6 hours to obtain polyamide-imide resin powder.

4,4'-dihydroxydiphenylsulfone (bisphenol S), which is an antioxidant, was added to the obtained polyamide-imide resin powder in an amount of 5 parts by weight based on the polyamide-imide resin powder. After further mixing this with a mixer, the mixture was heated to 290-300°C.

Perform melt crosstalk with a Brabender at 30 rpm, then
Extrusion was performed to obtain a pellet-shaped polyamide-imide resin composition.

Example 2 A pellet-shaped polyamide-imide resin composition was obtained in exactly the same manner as in Example 1, except that 10% by weight of bisphenol s, an antioxidant, was added to the BoIJ 7 mid-imide resin powder.

Example 3 A pellet-shaped polyamide-imide resin composition was obtained in exactly the same manner as in Example 1, except that 20% by weight of acid and bisphenol St-polyamide-imide resin powder as an antioxidant were added.

Comparative Example 1 When the polyamide-imide resin powder obtained in Example 1 (product without antioxidant added) was kneaded in a Brabender at 290 to 300°C and 30 rpm, the resin reached a high temperature about 10 minutes after starting mixing. hardened by oxidation. This material was insoluble and infusible.

Comparative Example 2 Although 0.5 weight of bisphenol S as an antioxidant was added to the polyamide-imide resin powder obtained in Example 1, the same results as in Comparative Example 1 were obtained.

The melt flow properties, Tg and bending strength of injection molded products of the polyamide-imide resin compositions of Examples and Comparative Examples were tested by the following methods. The evaluation results are shown in Table 1.

Melt flowability: 1.5g of a sufficiently dried sample was placed in a cylinder heated to 300°C and heated for 3 minutes.

The center nozzle of the die (diameter 1.0
mm, length 2 strokes) and measured using Shimabara Seisakusho's "Koka Type Flow Tester, CFT-500J".

Tg and bending strength of injection molded product: Injection molding (barrel temperature: 290℃~300℃.

Injection pressure 1500 to 9 f/mark 2 Mold temperature: 150℃
) was used to prepare a 1010 mm x 10 square molded product for bending test, and its bending strength was measured at room temperature (25° C.) using Shimabara & Autograph (Model IM-100).

In addition, the glass transition temperature (Tg) of the above molded product was
It was measured by the Expansion method using a thermophysical tester (TMS-1) manufactured by Elma Corporation.The results are shown in Table 1.

Claims (1)

[Claims] 1. Trimellitic anhydride or its derivative (I) and aromatic diamine (II) or aromatic diisocyanate (III), optionally further containing dicarboxylic acid (IV) and/or lactam (V) A polyamide-imide resin composition obtained by adding an antioxidant (VI) to a polyamide-imide resin obtained by reaction in a polar solvent. 2. The polyamide resin composition according to claim 1, wherein the antioxidant (VI) is a phenolic antioxidant having a melting point of 200°C or higher. 3. The polyamide-imide resin composition according to claim 1 or 2, wherein the amount of the antioxidant (VI) added is 1 to 40% by weight based on the polyamide-imide resin.