JPH0551015B2 - - Google Patents

Description

[Detailed description of the invention]

<Industrial Application Field> The present invention relates to a novel heat-resistant thermoplastic polymer. More specifically, the purpose is to provide a new thermoplastic aromatic polyamide-imide copolymer that has good thermal stability and fluidity, particularly in the temperature range of 300 to 400°C, and is injection moldable (hereinafter referred to as , polyamideimide is abbreviated as PAI). <Prior art> It is already well known that an aromatic PAI with excellent heat resistance can be obtained by polycondensing an aromatic tricarboxylic acid anhydride or its derivative with an aromatic diamine or its derivative (for example,
(Special Publication No. 42-15637, Publication No. 19274-1974, Publication No. 2397-1977, etc.) As an example related to the present invention, British Patent No. 1032649 describes trimellitic anhydride chloride and 2,2-
General formula synthesized from bis(p-aminophenyl)propane In JP-A-49-129799, the PAI represented by The PAI expressed as is disclosed. <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 fluidity during molding and the total balance of physical properties of the melt-molded product were not necessarily satisfactory. For example, P.A.I. Although it has excellent heat resistance during melt molding, the toughness and mechanical properties of the molded product are unsatisfactory, and it is not practical as a molding material. Also PAI The difference between the flow start temperature and the thermal decomposition temperature is 50℃ or more, and the thermal stability and fluidity during melt molding are excellent, so it shows good melt moldability, but the flexibility of the diamine component is high. As a result, the physical properties (especially bending strength and thermal properties) of the molded product do not necessarily reach a satisfactory level. Therefore, the present inventors obtained an aromatic PAI that has good melt moldability by combining good thermal stability and fluidity in the temperature range of 300 to 400°C, and has an excellent balance of physical properties in a molded product. As a result of intensive research aimed at this purpose, we have developed a new thermoplastic aromatic PAI copolymer that has the desired properties by combining two different specific aromatic diamine components in a hitherto unknown composition. The present invention was achieved by discovering that the following can be obtained. <Means for solving the problems> That is, the present invention has the following formula:

Structural unit of [formula], B formula Structural unit of and C formula The ratio of each structural unit is 1 mole of B+C to 1 mole of A, and B0.1~
Structural units A and B in which C is 0.9 to 0.1 mole relative to 0.9 mole, and the logarithmic viscosity measured at 30° C. at a polymer concentration of 0.5% by weight in an N-methyl-2-pyrrolidone solvent is 0.25 to 0.55; A thermoplastic aromatic polyamide-imide copolymer in which the polyamide-imide units of A and C are randomly arranged (however, Z in the formula is 3 in which two of the three functional groups are bonded to adjacent carbons).
Functional aromatic group, R ₁ is an alkyl group or alkoxy group having 1 to 4 carbon atoms, Y is

【formula】

【formula】 or

[Formula] group, X is Y,

[Formula] or -SO ₂ - group, R ₃ is an alkyl group having 1 to 4 carbon atoms, a fluorine-substituted alkyl group, or an aromatic group having 6 to 9 carbon atoms, Q is a direct bond,

[Formula] - CH ₂ -, -O-, -S-, -NH-CO- or -
SO ₂ −, a is an integer from 1 to 4, b is 0 or 1 to 4
The integer c represents 0, 1 or 2. ). The thermoplastic aromatic PAI copolymer of the present invention is mainly composed of the three units indicated by A, B, and C above, and is a copolymer in which the polyamide-imide units of the structural units A and B and A and C are randomly arranged. It is. Z in the A unit is a trifunctional aromatic group in which two of the three functional groups are bonded to adjacent carbons, for example,

【formula】

【formula】

【formula】

【formula】

【formula】

【formula】

【formula】

[Formula] etc. As a specific example of B unit, for example, and side chain substituted derivatives thereof. As a specific example of C unit, for example, and side chain substituted derivatives thereof. The ratio of each of the above units in the PAI copolymer of the present invention is such that B + C is 1 mole per mole of A, and C is 0.9 to 0.1 mole to 0.1 to 0.9 mole of B, preferably B0.2 to 0.1 mole. C is 0.8 to 0.2 mole relative to 0.8 mole. If the C unit exceeds 90 mol% of B+C, the resulting PAI molded product will become noticeable and brittle, which is unsuitable. On the other hand, as the C units in B+C decrease, the thermal properties (especially the heat distortion temperature) of the resulting PAI tend to decrease. % or more. In addition, A' unit when the imide bond in the above A unit remains in the state of an amic acid bond as its ring-closing precursor.

[Formula] is a part of the A unit, for example, 50 mol% or less of the A unit,
Preferably, the presence of 30 mol% or less is also included in the scope of the present invention. The PAI copolymer of the present invention can be produced using any of the many general production methods that have been proposed to date, but the following three methods are representative of the most practical. can be mentioned. (1) Isocyanate method: A method in which imidodicarboxylic acid synthesized from aromatic tricarboxylic anhydride and/or aromatic tricarboxylic anhydride/aromatic diamine (2/1 molar ratio) is reacted with aromatic diisocyanate (for example, Kosho 44-
Publication No. 19274, Publication No. 45-2397, Special Publication No.
50-33120, 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. 15637/1983). (3) Direct polymerization method: A method in which aromatic tricarboxylic acids or their derivatives (excluding acid chloride derivatives) and aromatic diamines are directly reacted in the presence of a dehydration catalyst in a polar organic solvent (for example,
Publication No. 4077). Among the three methods mentioned above, the acid chloride method has the advantages of relatively easy raw material procurement and the fact that it is easy to obtain PAI with a high degree of polymerization with excellent linearity (less branched structure) through low-temperature solution polymerization. This is the most recommended manufacturing method. Here, a more specific example of the production of the PAI copolymer of the present invention by the acid chloride method is as follows. That is, 1 mol of aromatic tricarboxylic acid anhydride monochloride and 0.9 to 1.1 mol of a mixed diamine consisting of 10 to 90 mol% of aromatic diamine of the following formula () and 90 to 10 mol% of aromatic diamine of the following formula (). Soluble in organic polar solvents. (Here, Y is

【formula】

[expression] or

[Formula] group, X is Y,

[Formula] or -SO ₂ - group, R ₁ is an alkyl group with 1 to 4 carbon atoms or an alkoxy group, R ₃ is an alkyl group with 1 to 4 carbon atoms, a fluorine-substituted alkyl group, or a 6-carbon group
~9 aromatic group, Q is a direct bond,

[Formula] - CH ₂ -, -O-, -S-, -NH-CO- or -
SO ₂ −, a is an integer from 1 to 4, b is 0 or 1 to 4
The integer c represents 0, 1 or 2. ) Next, this is heated at a temperature of -20 to 80℃ for 0.5 to 10
Polymerization progresses over time. At this time, the reaction is accelerated by adding a hydrogen chloride scavenger of about 0.9 to 2.0 mol per equivalent of acid chloride group as needed during the reaction. The polymer produced in this step contains the majority (for example, 50 to 100%) of the A units of the PAI copolymer of the present invention in the amido-amic acid units of the ring-closing precursor. The structure has been converted into the so-called polyamide/amic acid. The organic polar solvent used in this first step is N/N- such as dimethylacetamide.
These include dialkylcarboxylic acid amides, N-methylpyrrolidone, heterocyclic compounds such as tetrahydrothiophene-1,1-dioxide, and phenols such as cresol and xylenol. In particular, N-methylpyrrolidone and N.N. -dimethylacetamide is preferred. Hydrogen chloride scavengers added as necessary in the first step include aliphatic tertiary amines such as trimethylamine, triethylamine, tripropylamine, and tributylamine, pyridine, lutidine, collidine, and quinoline. These include cyclic organic bases, organic oxide compounds such as ethylene oxide, propylene oxide, and the like. The polyamide amic acid obtained in the above first step is subsequently subjected to a second dehydration ring closure step and converted into the PAI copolymer of the present invention. The dehydration ring closure operation is carried out either by liquid phase ring closure in solution or solid phase thermal ring closure by heating in a solid. 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 ring closure method. The chemical ring closure method is
Using chemical dehydrating agents such as acetic anhydride, aliphatic anhydrides such as propionic anhydride, _{P2O5 ,} etc. at 0 temperature.
Performed at ~120°C. In addition, the liquid phase thermal ring closure method is
This is carried out by heating the polyamide/amic acid solution to 50 to 400°C, preferably 100 to 250°C. In this case, it is more effective to use an azeotropic solvent useful for water removal, such as benzene, toluene, xylene, chlorobenzene, etc. in combination. Solid phase thermal ring closure is performed by first isolating a polyamide/amic acid polymer from the polyamide/amic acid solution obtained in the first step and heat-treating it in a 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 heat treatment is usually selected from conditions of 150 to 350°C and 0.5 to 50 hours to ensure the desired ring closure rate and melt fluidity. If the treatment is carried out in the 250 to 350°C range for too long, the polymer itself tends to form a three-dimensional crosslinked structure, which significantly reduces the fluidity during melting, so care must be taken. Specific examples of aromatic diamines represented by the above general formulas () and () include amino groups (- NH ₂ ). By the production method detailed above, the PAI copolymer targeted by the present invention can be obtained, but other copolymer components other than those constituting A units, B units, and C units are also produced in the reaction system. The melt processability of PAI,
It is possible and within the scope of the present invention to use and copolymerize in combination within a quantitative range that does not significantly reduce the physical properties. The PAI copolymer of the present invention has a structure in which the imide units are partially ring-opened amic acid bonds, but most of them have a ring-closed structure, and N
-Polymer concentration in methyl-2-pyrrolidone solvent
It is a high polymerization degree polymer with a logarithmic viscosity (ηinh) value of 0.25 to 0.55, preferably 0.30 to 0.55, measured at 0.5% by weight at 30°C, and can be used for various purposes as described below. Compression molding is performed by dry blending the PAI copolymer powder of the present invention with different polymers, additives, fillers, reinforcing agents, etc. as required, and then drying the powder at 300 to 400°C and under pressure.
It is carried out under conditions of 50-500Kg/ ^cm2 . Pressure molding and injection molding are performed by dry-blending the PAI copolymer of the present invention with different polymers, additives, fillers, reinforcing agents, etc. as necessary, or by extruding the same into pellets. It is fed to an extrusion molding machine or an injection molding machine and carried out under a temperature condition of 300-400°C. In particular, the aromatic PAI of the present invention
The copolymer has an excellent balance of thermal stability and flow properties in the 300-400°C range, and is useful for extrusion molding and injection molding. In addition, by further subjecting the molded product obtained by heating and melting molding the PAI copolymer of the present invention to heat treatment under high-temperature conditions, a molded product with further improved physical properties such as heat distortion temperature, tensile strength, bending strength, and friction and wear properties can be obtained. Obtainable. 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 at a temperature of 220°C or higher and below (glass transition temperature -5°C) of the molded product for 5 hours or more.
In particular, heating for 10 hours or more is appropriate. 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, the polymerization-finished solution can be applied in a dry or wet-dry casting process, or the isolated polymer can be melt-molded with appropriate additives as required. . Laminated boards are made by impregnating cloth or mat made of glass fiber, carbon fiber, asbestos fiber, etc. with a copolymer solution, then pre-curing it by drying/heating to obtain a prepreg.
It is manufactured by pressing under conditions of 50-300 kg/cm ² at ℃. 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) Wear resistance improvers: graphite, carborundum, silica powder, molybdenum disulfide, fluorine resin, etc. (b) Reinforcers: glass fiber, carbon fiber, boron fiber, silicon carbide fiber, carbon whisker, asbestos Fibers, asbestos, metal fibers, etc.
(c) Flame retardant improvers: antimony trioxide, magnesium carbonate, calcium carbonate, etc. (d) Electrical property improvers: clay, mica, etc. (e) Tracking resistance improvers: asbestos, silica, graphite, etc. f) Acid resistance improvers: barium sulfate, silica, calcium metasilicate, etc. (g) Thermal conductivity improvers: Metal powders such as iron, zinc, aluminum, copper, etc. (h) Others: glass beads, glass spheres, carbonic acid calcium, alumina,
It includes synthetic and natural compounds that are stable at temperatures above 300°C, such as talc, diatomaceous earth, hydrated alumina, mica, shirasu balloons, asbestos, various metal oxides, and inorganic pigments. <Examples> Hereinafter, the present invention will be further explained in detail with reference to Examples. Note that the values of %, parts, and ratios used in the examples are % by weight and % by weight, respectively, unless otherwise specified.
Parts by weight and weight ratio values are shown. In addition, the value of logarithmic viscosity (ηint), which is a guideline for the molecular weight of the polymer, is N
-Polymer concentration in methyl-2-pyrrolidone solvent
0.5%, measured at a temperature of 30°C. Note that measurements of various physical properties were performed according to the following methods. Bending stress...ASTMD790 Bending modulus... Heat deformation temperature...ASTMD648-56 (18.56Kg/ ^cm2 ) Example 1 Glass separable flask with internal volume 5 equipped with a stirrer, thermometer, and nitrogen inlet tube 2,2-bis(p-aminophenyl)propane (melting point 134-135) synthesized from aniline hydrochloride and acetone
℃) 135.8g (0.60mol), 4,4'-bis(4-aminophenoxy)diphenylsulfone 259.5g
(0.60 mol) and 2000 g of anhydrous N,N-dimethylacetamide were charged and stirred to obtain a homogeneous solution.
The reaction mixture was heated in a dry ice/acetone bath.
Cool to 10 °C and remove trimellitic anhydride chloride 253.
g (1.20 mol) was added in small portions at such a rate that the temperature of the polymerization system was maintained at -10 to -5°C. Stirring was continued for an additional hour at 20°C. Next, the polymerized liquid is gradually poured into water under high-speed stirring to precipitate the polymer into particles.Then, the precipitated polymer is crushed into a fine powder using an impact crusher, and then thoroughly washed with water and dehydrated. and then in a hot air dryer
After drying at 150° C. for 5 hours and then at 200° C. for 3 hours, about 535 g of polymer powder having a logarithmic viscosity of 0.55 was obtained. The theoretical structural unit formula and the corresponding molecular formula of the copolymer obtained here are as follows,
In addition, it has a structure in which A units and B or C units are alternately connected, and the elemental analysis results of the copolymer showed good agreement with the theoretical values as shown below. A

[Formula] (- C ₉ H ₄ N ₂ O ₃ )- B (-C ₂₄ H ₁₆ O ₄ S) - C

[Formula] (-C ₁₅ H ₁₄ ) - A/B/C=1.2/0.6/0.6 (mole ratio) 100/50/50 (mole ratio)

[Table] Next, the obtained copolymer powder was added with 0.5% tetrafluoroethylene resin (Asahi Glass Co., Ltd. "Aphron Polymist F-5") as a sun protection agent and 0.5% titanium oxide.
%, the pellets were fed to a Brabender Plastograph extruder (processing temperature 340-360°C) and extruded twice while being melt-kneaded to obtain uniformly blended pellets. Next, the obtained pellets are compression molded (processing temperature 330-360℃, pressure 50-100℃).
Kg/cm ² ) to prepare test pieces and measure their physical properties, and the results shown in Table 1 below were obtained.

[Table] Next, the compression molded test piece obtained under the same conditions as above was placed in a hot air dryer and dried at 150°C for a day and night, then heated to 245°C.
When heat treatment was performed for 24 hours at 260°C and then for 48 hours at 260°C, the physical properties after the heat treatment were as shown in Table 2 below, and were significantly improved compared to the results in Table 1.

[Table] Comparative Examples 1 and 2 271.6 g (1.2 mol) of 2,2-bis(p-aminophenyl)propane or 513.0 g (1.2 mol) of 4,4'-bis(p-aminophenoxy) diphenylsulfone was used as the diamine component. The same operations as in the first half of Example 1 were carried out except for using the polymer alone, to obtain 415 g of a polymer powder with a logarithmic viscosity of 0.63 and 635 g of a polymer powder with a logarithmic viscosity of 0.42, respectively. Next, using the obtained polymer, 0.5% of tetrafluoroethylene resin and 0.5% of titanium oxide were prepared in the same manner as in Example 1.
%, a melt-kneading operation was performed to obtain pellets. Next, this pellet was compression molded under the same conditions as in Example 1 to prepare a test piece, and its physical properties were measured.
Polymers obtained from propane have a bending strength of 620
It is extremely small at Kg/cm ² , while 4,
The polymer obtained from 4′-bis(p-aminophenoxy)diphenylsulfone has a heat distortion temperature of 238°C.
It was low. In this way, if each of the diamines used in Example 1 were used alone as the diamine component, only a molded product with extremely low strength and a molded product with low heat resistance could be obtained compared to Example 1, and Compared to No. 1, the total balance of physical properties is inferior. Example 2 2,2-bis(p-aminophenoxy1,4-phenylene)propane as diamine component 295.6
g (0.72 mol) and 1,1-bis(p-aminophenyl)-1-phenylethane (melting point 159-161
The logarithmic viscosity was 0.50 by performing all the same operations as in the first half of Example 1 except using 138.4 g (0.48 mol) of
560g of copolymer powder was obtained. The theoretical structural unit formula and the corresponding molecular formula of this copolymer are as follows, and the elemental analysis results also showed good agreement with this theoretical value. A

[Formula] (- C ₉ H ₄ N ₂ O ₃ )- B _{( -C27H22O2} ) _-C

[Formula] (-C ₂₀ H ₁₆ )- A/B/C=1.2/0.72/0.48 (mole ratio) 100/60/40 (mole ratio) Next, using the obtained copolymer, Example 1 and Similarly, 0.5% tetrafluoroethylene resin and titanium oxide
After blending 0.5%, a melt-kneading operation was performed to obtain pellets. Next, this pellet was compression molded under the same conditions as in Example 1 to prepare a test piece, and the physical properties were measured, and the following results were obtained.

[Table] Example 3 4,4'-bis(p-aminophenoxy) diphenyl sulfone 363.3g (0.84
mol) and 9,9-bis(p-aminophenyl)-10-anthrone (melting point 302-304°C) 135.5g
The same operations as in the first half of Example 1 were carried out except that (0.36 mol) was used to obtain 615 g of copolymer powder having a logarithmic viscosity of 0.45. This copolymer consisted of the following theoretical structural units and molecular formula, and the elemental analysis values also agreed well with the theoretical values. A

[Formula] (- C ₉ H ₄ N ₂ O ₃ )- B (-C ₂₄ H ₁₆ O ₄ S) - C

[Formula] (- C ₂₆ H ₁₆ O) - Next, using the obtained polymer, 0.5% tetrafluoroethylene resin and 0.5% titanium oxide were added in the same manner as in Example 1.
%, a melt-kneading operation was performed to obtain pellets. Next, test specimens were prepared by compression molding this pellet under the same conditions as in Example 1, and the physical properties before and after heat treatment were measured in the same manner as in Example 1, and the results shown in Table 3 below were obtained. It was done.

[Table] Comparative Examples 3 and 4 1,1-bis(p-aminophenyl)-1-phenylethane 346.1g (1.2 mol) or 9,9-bis(p-aminophenyl) as diamine component
The same operations as in the first half of Example 1 were carried out except that 451.8 g (1.2 mol) of -10-anthrone was used alone to obtain 475 g of a polymer powder with a logarithmic viscosity of 0.61 and 570 g of a polymer powder with a logarithmic viscosity of 0.41, respectively. Next, the obtained polymer was blended with 0.5% tetrafluoroethylene resin and 0.5% titanium oxide in the same manner as in Example 1, and then fed to a Brabender Plastograph extruder (processing temperature 340-360°C). When melt-kneading operation was carried out, 9,9-bis (p
The polymer obtained from -10-anthrone (aminophenyl) does not develop a smooth melt state, and the rotational torque applied to the extruder shaft exceeds the allowable limit of the device, making it virtually impossible to melt and knead it. Ta. On the other hand, 1,1-bis(p-aminophenyl)-1
- The polymer obtained from phenylethane could be blended into pellets, although the rotational torque value applied to the extruder rotating shaft was high. However, when this pellet was compression molded under the same conditions as in the second half of Example 1, the bending strength of the molded product obtained was
It was extremely small at 560Kg/ ^cm2 . If only the second component of the diamine used in Example 3 was used as the diamine component, only PAI, which is difficult to melt mold, could be obtained. Although melt molding is possible, only a molded product with extremely low strength compared to Example 2 can be obtained. Examples 4 to 8 Copolymers were obtained by carrying out the same operations as in Example 1 except for using the diamines shown in Table 4 as two components. These copolymers each had the theoretical structural unit formula shown in Table 4, and the elemental analysis results also agreed well with the theoretical values. Next, the obtained copolymer was compression molded (processing temperature 350-400℃, pressure 50-100Kg/cm ² ) to prepare test pieces, and physical properties were measured, and the results shown in Table 4 were obtained. Ta.

【table】

【table】

【table】

[Table] <Effects of the Invention> The PAI of the present invention has good melt moldability by having good thermal stability and fluidity in the temperature range of 300 to 400°C, and the physical property balance of the molded product is good. This makes it possible to produce high-performance materials and molded articles with high molding productivity through extrusion molding and injection molding. Utilizing their excellent heat resistance and mechanical properties, these materials and molded articles can be used to manufacture electrical and electronic components,
It is widely used in fields such as aerospace equipment parts, automobile parts, and office equipment parts.

Claims (1)

[Claims] 1 A structural unit of formula [formula], B formula Structural unit of and C formula The ratio of each structural unit is 1 mole of B+C to 1 mole of A, and B0.1 to
Structural units A and B in which C is 0.9 to 0.1 mole relative to 0.9 mole, and the logarithmic viscosity measured at 30° C. at a polymer concentration of 0.5% by weight in an N-methyl-2-pyrrolidone solvent is 0.25 to 0.55; A thermoplastic aromatic polyamide-imide copolymer in which polyamide-imide units A and C are randomly arranged. (However, Z in the formula is a trifunctional aromatic group in which two of the three functional groups are bonded to adjacent carbons, R ₁ is an alkyl group or alkoxy group having 1 to 4 carbon atoms, and Y is [Formula ] [Formula] or [Formula] group, X is Y, [Formula] or -SO ₂ - group, R ₃ is an alkyl group having 1 to 4 carbon atoms, a fluorine-substituted alkyl group, or an aromatic group having 6 to 9 carbon atoms group, Q is a direct bond, [Formula] -CH ₂ -, -O-, S-, -NH-CO- or -SO ₂ -, a is an integer of 1 to 4, b is 0 or an integer of 1 to 4 , c indicates 0, 1 or 2.)