JPS62209138A - Thermoplastic aromatic polyamideimide copolymer - Google Patents

Abstract

PURPOSE:To obtain the titled copolymer outstanding in fluidity and melt formability, suitable for automobile parts, etc., by copolymerization between an aromatic tricarboxylic acid anhydride and each specific aromatic diamine having aryl ether bond and diamine having m-phenylene unit. CONSTITUTION:(A) 1mol of an aromatic tricarboxylic acid anhydride monochloride and (B) 0.9-1.1mol of a mixed diamine made up of (i) 10-95mol% of an aryl ether bond-carrying aromatic diamine corresponding to structural unit of formula II (R is 1-4C alkyl, etc.; a is 0-2; b is 1-4) and (ii) 90-5mol% of an m-phenylene-contg. diamine corresponding to structural unit by formula III (X is amide) are dissolved in a polar solvent (e.g. cresol), being brought to reaction followed by dehydration on heating, thus obtaining the objective polymer constituted by structural units of formula I (Z is aromatic group), II and III, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention provides a molded article that has both good thermal stability and fluidity particularly in the temperature range of 300 to 400°C, is injection moldable, and has desirable properties. The present invention relates to a novel thermoplastic aromatic polyamide-imide copolymer (hereinafter, polyamide-imide is abbreviated as FAI).

<Prior art> By polycondensing an aromatic tricarboxylic acid anhydride or its derivative with an aromatic diamine or its derivative,
It is already well known that aromatic FAI with excellent heat resistance can be obtained (for example,
-15,637 Publication, Japanese Patent Publication No. 19,274 (1974), Publication No. 2,397 (1977), Publication No. 49-497,
077 Publication, Special Publication No. 50-33,120, etc.)
.

<Problems to be solved by the invention> However, when the aromatic PAIs that have been generally proposed so far are intended to be used as melt molding materials, they have poor thermal stability during melt molding, The total balance of fluidity and physical properties of the melt-molded product was not always satisfactory.

For example, the general formula synthesized from trimellitic anhydride chloride and 4,4'-cya-based nodiphenyl ether
Polyamide-imide represented by
15,637) has excellent heat resistance, but
Since the flow start temperature and the thermal decomposition temperature are too close, melt molding is practically impossible.

In addition, aromatic polyamideimide represented by the general formula synthesized from trimellitic anhydride chloride and 4,4'-diaminobenzanilide has excellent heat resistance, but its flow initiation temperature is higher than the decomposition temperature, so it cannot be melt-molded. difficult to do.

In addition, trimellitic anhydride and m-amide group-containing diamines such as 3,3'-diaminopenzanilide, 3,4'-diaminobenzanilide, and 4,3'-diaminobenzanilide (hereinafter referred to as these diamines) Aromatic polyamideimides synthesized from m-aramid diamine (generally referred to as m-aramid diamine) can be melt-molded, but they have poor toughness and the physical properties (especially bending strength) of the molded products are not always good. However, it has not yet reached a satisfactory level.

Therefore, the present inventors have solved these problems of PAI, and have achieved good melt moldability by having both good thermal stability and fluidity in the temperature range of 300 to 400°C, and molded products. As a result of intensive studies aimed at obtaining an aromatic FAI with an excellent balance of physical properties,
The present invention was achieved by discovering that it is extremely effective to copolymerize a specific aramid diamine with an aromatic diamine having a specific 7lyl ether bond.

Means for Solving the Problems〉 That is, the present invention has the following structural units: and the ratio of each structural unit is substantially 1 mol of B+C to 1 mol of A, and B/C is 10 to 95 Mol%/9
A thermoplastic aromatic polypumidoimide copolymer characterized in that the amount is 0 to 5 mol% (however, Z in the above formula is a trifunctional OHHO aromatic compound in which a difunctional group is bonded to an adjacent carbon). group group, X is -C-N- group or -N-C- group, R is an alkyl group having 1 to 4 carbon atoms or a halogen group, a is 0,
(2) or 2, b represents 0 or an integer from 1 to 4; ).

The thermoplastic polyamide-imide copolymer of the present invention is mainly composed of three units represented by A1B and C above.

Z in the above A unit is a trifunctional aromatic group in which two of the three functional groups are bonded to adjacent carbons, and for example, the imide bond in the above A unit is its ring-closing precursor. The scope of the present invention also includes the case where the A' unit remains in an amic acid bonded state as a part of the A unit, for example, 50 mol % or less, preferably 30 mol % or less.

Specific examples of the above B unit include, for example, etc. and their side chain substituted derivatives. In particular, the above C unit is a divalent diphenylamide group containing at least one m-phenylene, and specific examples include can give.

Each of the above units in the polyamide-imide copolymer of the present invention has a structure in which the proportions of component A and component CB+C) are substantially equimolar, and component A and component B or component C are alternately connected.

The composition ratio of component B and component C as diamine residues is B/C of 10 to 95 mol%/90 to 5 mol%.
, preferably 20 to 90 mol% and 780 to 10 mol%. If the proportion of B units in the B+C units is 95 mol % or more, the resulting copolymer will have significantly lower fluidity during melting, making melt molding substantially difficult, which is not preferable. Furthermore, if the proportion of B units in the B+C units is less than 10 mol %, the toughness of the copolymer will decrease and the strength will decrease significantly, which is not preferable.

The PAI copolymer of the present invention can be produced using any of the many general production methods proposed so far, but the following two methods are representative examples of highly practical methods. can be mentioned.

(1) Isocyanate method: A method of reacting an aromatic diisocyanate with imidodicarboxylic acid synthesized from aromatic tricarboxylic anhydride and/or aromatic tricarboxylic acid anhydride/aromatic diamine (2/1 molar ratio) (for example, Publication No. 44-19,274, Special Publication No. 4
Publication No. 5-2,397, Special Publication No. 50-33, 120
Publications, etc.).

(2) Acid chloride method: A method in which aromatic tricarboxylic acid anhydride chloride and aromatic diamine are reacted (for example, Japanese Patent Publication No. 15,637/1984).

Among the above two methods, the acid chloride method has the advantage that raw materials are relatively easy to procure, and high polymerization degree FAI with excellent linearity (few branched structures) can be easily obtained by low-temperature solution polymerization. This is the most recommended manufacturing method. Here, the PAI of the present invention by the acid chloride method
A more specific example of the production of the copolymer is as follows. That is, 1 mol of aromatic tricarboxylic acid anhydride monochloride and 10 aromatic diamines of the following formula (I)
~95 mol% and aromatic diamine of the following formula (n) 90-5
0.9 to 11 moles of a mixed diamine consisting of mol % is dissolved in an organic polar solvent.

(However, in the formula, R is an alkyl group having 1 to 4 carbon atoms or a halogen group, a is 0, 1 or 2, b is an integer of 0 or 1 to 4, and X is a temperature condition of -20 to 80°C. After mixing for approximately 0.5 to 1 hour, add 0% hydrogen chloride scavenger if necessary.
．． When about 8 to 2 moles of L are added to accelerate the polymerization reaction rate, the polymerization reaction is completed at around room temperature in a reaction time of 0.5 to 10 hours. The polymer produced at this stage is the PA of the present invention.
Most of the A units of the I copolymer (e.g. 50-1009
6) is replaced with an amide/amic acid unit of a ring-closing precursor, resulting in a so-called polyamide/amic acid. The organic polar solvent used in this first step includes N-N-dialkylcarboxylic acid amides such as N-N-dimethylacetamide and N-N-diethylacetamide, N-methyl-
These include heterocyclic compounds such as 2-pyrrolidone and tetrahydrothiophene-1.I-dioxide, and phenols such as cresol and xylenol, with N-methyl-2-pyrrolidone and N-N-dimethylacetamide being particularly preferred.

Hydrogen chloride scavengers added as necessary in the first step include aliphatic tertiary amines such as trimethylamine, triethylamine, tripropylamine, and tributylamine, and cyclic scavengers such as pyridine, lutidine, collidine, and quinoline. These include organic bases and organic oxide compounds such as ethylene oxide and propylene oxide.

The polyamide/amic acid obtained in the first step is then subjected to a second dehydration ring closure step and converted into the polyamide-imide copolymer of the present invention.

The dehydration ring closure operation is carried out either in liquid phase ring closure in solution or in solid phase thermal closure heating with solids. There are two types of liquid phase ring closure: a liquid phase chemical ring closure method using a chemical dehydrating agent, and a simple liquid phase thermal closure method. The chemical ring closure method is carried out using a chemical dehydrating agent such as acetic anhydride, aliphatic anhydride such as propionic anhydride, P2O5, etc. at a temperature of 0 to 120C (preferably 10 to 60C). In addition, the liquid phase thermal closed monkey method is
This is carried out by heating the polyamide/amic acid solution to 50 to 400°C (preferably 100 to 250°C). At this time, it is more effective to use an azeotropic solvent useful for removing water, such as benzene, toluene, xylene, chlorobenzene, etc. in combination. In solid-phase thermal confinement, first, polyamide/amic acid solution obtained in the first step is processed into polyamide/amic acid solution.
This is carried out by isolating the amic acid polymer and heat-treating it in the solid state. As a precipitant for isolating the polyamide/amic acid polymer, a liquid such as water, methanol, etc., which is miscible with the reaction mixture solvent but in which the polyamide/amic acid itself is insoluble, is employed. The solid-state heat treatment is usually selected from conditions of 150 to 350°C and 0.5 to 50 hours so as to ensure the desired ring closure rate and melt fluidity.

If the treatment is carried out for too long in the range of 250 to 350°C, the polymer itself tends to form a three-dimensional crosslinked structure, which significantly reduces the fluidity during melting, so care must be taken.

In addition, the specific examples of the aromatic diamines fI+ and (II) above have amino groups (N
Hz).

Incidentally, specific examples of the aromatic diamine represented by the above general formula +I) include the following structural formulas.

Specific examples of the aromatic diamine represented by the above general formula (n) are as follows in terms of structural formulas.

H H Although the PAI copolymer targeted by the present invention can be obtained by the production method detailed above, A units and B units are further added to the reaction system.
It is possible to use and copolymerize other copolymerization components other than the components constituting the unit and C unit in combination within a quantitative range that does not significantly reduce the melt processability and physical properties of FAI. , within the scope of the present invention.

The aromatic PAI copolymer of the present invention has a structure in which the imide unit remains partially broken amic acid bonds, but most of it has a closed ring structure, and also has an N-methyl-2
- Polymer concentration 0.5% by weight in pyrrolidone 'ffl K
, the value of the logarithmic viscosity (ηinh) measured at 30°C is 0.
It is a polymer with a high polymerization degree of 20 or more, preferably 0.25 or more, and can be used for various purposes as described below.

Compression molding is performed by tri-blending the PAI copolymer powder of the present invention with different polymers, additives, fillers, reinforcing agents, etc. as necessary, and then processing the mixture at a temperature of usually 300 to 400°C and a pressure of 50 to 500°C.
It is carried out under the condition of kg/ff12. In addition, extrusion molding and injection molding are performed using a tri-blend of the PAI copolymer of the present invention with a true polymer, an additive, a filler, a reinforcing agent, etc. as required, or a pellet obtained by pelletizing this by extruding it. It is supplied to an extrusion molding machine or an injection molding machine and carried out under a temperature condition of 300 to 400°C. In particular, the aromatic PAI copolymer of the present invention has an excellent balance of thermal stability and fluidity in the range of 300 to 400°C, and is useful for extrusion molding and injection molding. Furthermore, by further subjecting the molded article obtained by heating and melting molding the PAI copolymer of the present invention to heat treatment under high-temperature conditions, physical properties such as heat distortion temperature, tensile strength, bending strength, and friction and wear characteristics were further improved. Molded products can be obtained. Such heat treatment conditions include heating the molded product at a temperature of 200°C or higher and below the glass transition temperature of the molded product, particularly 220°C or higher and below (glass transition temperature -5°C) of the molded product for 5 hours or more, especially 10 hours or more. It is appropriate to heat it. If the heat treatment temperature exceeds the glass transition temperature of the molded article, the molded article is undesirably deformed during the heat treatment and has a strong tendency to impair its practicality. There are no particular restrictions on the equipment for this heat treatment, but a normal electric heating oven can suffice to achieve the purpose.

For film and fiber manufacturing applications, polymerization termination solutions can be applied in dry or wet-dry casting processes;
Isolated polymer again? Melt molding can also be carried out by adding appropriate additives if necessary. The laminate is made of fiberglass,
After impregnating a cloth or mat made of carbon fiber, asbestos fiber, etc. with a polymer solution, pre-curing is performed by drying/heating to obtain a prepreg.
It is manufactured by pressing under the conditions of 00°C and 50 to 300 kg/cN2.

For paint applications, different types of solvents may be added and mixed to the polymerization-completed solution as needed, and then the concentration may be adjusted and used for practical use as is.

The composition of the present invention may contain the following fillers in an amount of 70% by weight or less, if necessary. (a
l Abrasion resistance improvers: graphite, carborundum, silica powder, molybdenum disulfide, fluororesin, etc. (b) Reinforcers: glass fiber, carbon fiber, boron fiber, silicon carbide fiber, carbon whisker, asbestos fiber, asbestos, metal Fibers, etc., (C) @flammability improvers such as antimony dioxide, magnenium suboxide, calcium carbonate, etc., fdl
! Easeability improvers: clay, mica, etc., °(el tracking improvers: asbestos, silica, graphite, etc.)
f) Acid resistance improvers: barium sulfate, silica, calcium metasilicate, etc. (gl) Thermal conductivity improvers: iron, zinc,
Metal powders such as aluminum and copper, (HL and other glass beads, glass bulbs, ceremonial calcium, alumina, talc, diatomaceous earth, water alumina, mica, shirasu balloons, asbestos, various metal oxides, inorganic pigments, etc.) at 300℃
The above-mentioned stable synthetic and natural compounds are included.

<Examples> Hereinafter, the present invention will be further described in detail using Examples and Comparative Examples. Note that the logarithmic viscosity (η
1nh) in N-methyl-2-pyrrolidone solvent,
Measurements were made at a polymer concentration of 0.5% and a temperature of 30°C. Further, the glass transition temperature (Tg) was measured using a PerkinElmer 1B type DSC device.

Note that measurements of various physical properties were performed according to the following methods.

Bending strength (FS) ... ASTM D79
0 Flexural Modulus (FM) ・・・・ASTM D
790 heat y-type temperature ()iDT)・・・・ASTM
D-648 (18,55 kg/cm2) Examples 1 to 4 and Comparative Examples 1 to 2 Internal volume 5 equipped with stirrer, thermometer and nitrogen gas inlet tube
After charging 4,4'-reaminodiphenyl ether (DDE) and 3,4'-diaminobenzanilide (3,4'-DABA') with the composition shown in Table 1 into a separable glass flask, anhydrous N was added. 3 OOOg of -N-dimethylacetamide (DMAC) was added and stirred to obtain a homogeneous solution.

The mixture was cooled in a water bath, and 589.6 g (2.8 mol) of trimellitic anhydride monochloride (TMAC) was added in small portions at a rate that did not exceed the internal temperature of 30°C. Next, after stirring for 2 hours, pyridine 350
m4 and 750 m/(about 7.5 mol) of acetic anhydride were added and stirred for 30 minutes to complete the reaction.

Next, the polymerization finished liquid was gradually poured into water under high speed stirring to precipitate the polymer in powder form, which was thoroughly washed with water/dehydrated, and then heated in a hot air dryer at 150°C for 5 hours. 200
After drying at ℃ for 3 hours, the logarithmic viscosity and glass transition temperature (Tg
) was obtained.

The theoretical structural unit formula and molecular formula of the copolymer obtained in Example 1 are as follows, and it has a structure in which A units and B or C units are alternately connected. The elemental analysis results showed good agreement with the theoretical values as shown in Table 2.

A/B/C = 2.80/2.1010.70 (molar ratio) = 100/75/25 (mol%) In addition, the elemental analysis results of the polymers of Examples 2.3 and 4 are also good as the theoretical values. showed agreement.

Next, 2% by weight of tetrafluoroethylene resin (Asahi Glass Co., Ltd. °1 Aphron Bolimist F-5") was added as an anti-seize agent to the obtained copolymer powder, and then a Brabender Plastograph Extruder was used. (Processing temperature 300-360℃
) to obtain melt-extruded pellets.

However, the polymer powder of Comparative Example 1 had an abnormally high melt viscosity, and it was impossible to pelletize it by melt-kneading/extrusion.

Next, the obtained pellets were molded into a small injection molding machine (processing temperature: 30
0~350℃, injection pressure 1.400~1.700 kg
/a+2) to prepare a test piece, and the molded test piece was placed in a hot air dryer and heat-treated at 200°C for 24 hours, at 250°C for 24 hours, and then at 260°C for 24 hours. Subsequently, physical properties were measured, and the results shown in the column of properties of molded product after heat treatment in Table 1 were obtained. The molded product obtained in Comparative Example 2 was more brittle and had lower bending strength than the molded products of Examples 1 to 4.

Table l Table 2 Elemental analysis results of the polymer of Example 1 Examples 5-
7 and Comparative Example 3 Polymerization/post-treatment/blending/extrusion/injection in the same manner as in Example 1 except that 3,4'-DABA was changed to 4,3'-diaminobenzanilide (4,3'-DABA). Test pieces were obtained by molding, and the properties of the test pieces before and after heat treatment were measured, and the results are summarized in Table 3. The molded products of Comparative Example 3 are those of Examples 5-
Compared to the molded product No. 7, it was brittle and only had low bending strength.

The polymer of Example 5 had the following theoretical structural formula, and the elemental analysis results showed good agreement with the theoretical values as shown in Table 4.

A/B/C=2.80/2.2410.56 (molar ratio)=100/80/20 (mol%) Also, the elemental analysis results of the polymers of Examples 6 and 7 also agree well with the theoretical values. showed that.

Table 3 Table 4 Elemental analysis results of the polymer of Example 5 Examples 8-
IO and Comparative Example 4 Example 1 except that 3,4'-DABA was changed to 3,3'-diaminobenzanilide (3,3'-DABA)
Polymerization/post-treatment/compounding/extrusion/injection molding were performed in the same manner as above to obtain test pieces, and the properties after heat treatment were measured. The results are summarized in Table 5.

The molded product of Comparative Example 4 was more brittle than those of Examples 8 to 11, and only had low bending strength.

The polymer of Example 8 had the following theoretical structural formula, and the elemental analysis results showed good agreement with the theoretical values as shown in Table 6.

(JH A/B/C=2.80/19610.84 (molar ratio)=100/70/30 (mol%) The elemental analysis results of the polymers of Examples 9 and 10 also showed good agreement with the theoretical values. Indicated.

Table 5 Table 6 Elemental analysis results of the polymer of Example 8 Example 11 408.8 g (1.4 mol) of 1,3-bis(p-7 minophenoxy)benzene and (3. The polymerization and post-treatment operations were carried out in the same manner as in Example 1, except that 318.2 g (1.4 mol) of 4'-DABA was used. As a result, ηinh ~0.66.
Tg=280°C (7) A polymer powder was obtained.

This polymer has the following theoretical structural formula, and the elemental analysis results showed good agreement with the theoretical values.

H A/B/C=2.80/1.40/L40 (molar ratio)=tgo,,'so,,'so (mol%) Next, 3% by weight of titanium oxide was added to the obtained polymer powder. After the addition, it was fed to a Brabender Plastograph extruder (processing temperature 300-360°C) to obtain melt-extruded pellets.

Next, the obtained pellets were compression molded (processing temperature 330-3
A test piece was prepared at 60°C and a pressure of 50 to 100 kg/n2), and the formed test piece was placed in a hot air dryer for 15 minutes.
After drying at 0°C overnight, at 220°C for 101 Rj, 245
C. for 14 hours, followed by heat treatment at 260.degree. C. for 48 hours. Subsequently, physical properties were measured and the following results were obtained. FS = 1.80'Okg/ill"
, FM = 40,000kg/w2. HDT =
279℃.

Example I2 572.3 g (196 mol) of 1,4-bis(p-aminophenoquine)benzene and 190.9 g (0,84 mol) of 3,3'-DABA as aromatic diamine mixture
A polymer having the following properties was obtained by carrying out the same operations as in Example 11, except that mol) was used.

y) inh = 0.72 Tg = 281℃ FS = 1,700kg/l”j12FM
=38,000kg10++2k(L)T=
280°C This polymer has the following theoretical structural formula, and the elemental analysis results showed good agreement with the theoretical values.

A/B/C=2.80/L9610.84 (molar ratio)=100/70/30 (mol%) <Effects of the invention> The FAI of the present invention has good thermal stability in the temperature range of 300 to 400°C. It has good melt moldability due to its combination of properties and fluidity, and the physical properties of the molded product are well balanced.Extrusion molding and injection molding allow high-performance materials and molded articles to be produced with high molding productivity. can be produced. These materials and molded articles take advantage of their excellent heat resistance and mechanical properties to be used in electrical and electronic parts, aerospace equipment parts, and more.

Widely used in fields such as automobile parts and office equipment parts.

Claims (1)

[Claims] A, a structural unit of the formula ▲ has a mathematical formula, a chemical formula, a table, etc.; B, a structural unit of the formula ▲ has a mathematical formula, a chemical formula, a table, etc.; and C, a structural unit of the formula ▲ has a mathematical formula, a chemical formula, a table, etc. It consists of the structural units ▼, and the ratio of each structural unit is substantially 1 mole of B+C per mole of Al, and B/C is 10 to 95 mole%.
/90 to 5 mol% of a thermoplastic aromatic polyamide-imide copolymer. (However, Z in the above formula is a trifunctional aromatic group in which two of the three functional groups are bonded to adjacent carbons, and X is a ▲ mathematical formula, chemical formula, table, etc. ▼ group or ▲ mathematical formula, chemical formula ,
There are tables, etc. ▼ group, R is an alkyl group with 1 to 4 carbon atoms or halogen group, a is 0, 1 or 2, b is 0 or 1
Indicates an integer of ~4. )