JPH02281077A - Production of polymer composite material - Google Patents

Abstract

PURPOSE:To obtain a polymer composite material having high-performance mechanical and thermal properties by containing a coagulant component in a polymer solution composed of a specific reinforcing polymer, matrix polymer and solvent and forming a film therefrom. CONSTITUTION:A polymer composite material obtained by containing (D) 1 to 8% component constructing a coagulant in a polymer solution composed of (A) a reinforcing polymer composed of a polyazole having substantially a rodlike skeleton, (B) a matrix polymer (e.g. an aliphatic polyamide or aromatic polyamide) having fusibility and (C) a solvent (e.g. concentrated sulfuric acid or methanesulfonic acid), introducing the resultant solution into a coagulating bath and forming a film. A mixed aqueous solution of water and a solution using water is used as the component (D).

Description

[Detailed description of the invention]! Because of its dramatically improved physical properties, IN-reinforced plastics have been regarded as important as load-bearing structural materials, and various materials have been developed and put into practical use. The production of such composite materials requires a process of arranging separately manufactured reinforcing fibers in one direction, and a process of impregnating the fibers with a matrix, which also includes a process in an autoclave. ! Requires cumbersome step-by-step operations.

On the other hand, the strength and durability of composite materials are largely influenced by the state of the interface between the reinforcing fibers and the matrix polymer. Since the fibers themselves are macroscopic at the interface between the two, defects existing there propagate macroscopically and lead to destruction of the composite material.

In order to solve this drawback, instead of using fibrous reinforcing material that can only be dispersed in a macroscopic form, a high modulus reinforcing polymer and a matrix polymer are dissolved in a common solvent, and both can be dispersed in a microscopic form. We are considering manufacturing a polymer composite in which the reinforcing polymers are dispersed and mixed in an extremely microscopic state by mixing them in a molecular order, solidifying and molding them, and in which the reinforcing polymers are oriented. It has been.

The present inventors currently use polyazole-based polymers such as poly-p-phenylenebenzobisthiazole, which provide excellent tensile modulus, as reinforcing polymers in organic polymeric fibers, and in various combinations with various matrix polymers. Although studies have been carried out on increasing the modulus of the polymer, there have been drawbacks such as a low tensile modulus compared to the additivity value expected when the polymer component is sufficiently oriented. In addition, in order to obtain a molded product in which polymer composite films are laminated, it is advantageous to increase the thickness of the film, but in conventional wet molding, increasing the thickness deteriorates coagulation. However, a good film could not be obtained.

In order to solve this problem, the present inventors used a polyazole polymer such as poly-p-phenylenebenzobisthiazole as a reinforcing polymer, and developed a system using a flexible polymer as a matrix polymer. The present invention was arrived at as a result of intensive studies on making the film more modular and thicker.

Purpose of the Invention As a result of intensive research in order to obtain a polymer composite with high performance mechanical and thermal properties, the present inventor has discovered that the main component of a coagulant is added to a polymer composite solution before solidification using an appropriate stone. The present invention was achieved by discovering that an excellent polymer composite can be obtained even in a thick film by forming a film containing the following.

That is, the present invention provides a polymer composite solution mainly containing a reinforcing polymer (A) consisting of a polyazole having a substantially rod-shaped skeleton, a matrix polymer (B) forming a fusible fabric, and a solvent (C). In a method for producing a polymer composite that involves introducing the polymer composite into a coagulation bath and forming a film, it is confirmed that the polymer composite solution contains at least 1% or more of a component constituting a coagulant. This invention relates to a method for producing a characteristic polymer composite.

The reinforcing polymer (A) used in the present invention has the following formula [wherein, X represents -S-, -O-, or -NH-, and the bonds (a) and (b) are further azole It is a bond that forms a ring or a hydrocarbon ring, or a hydrogen atom is bonded to one of them and the other is a bond. ] Examples include substantially rod-shaped voriazoles having an azole skeleton represented by
There are polymers described in US Pat. No. 207,407,
Among them, polyazoles such as poly-p-phenylenebenzobisthiazole, poly-p-phenylenebenzoxazole, and poly-p-phenylenebenzosimidazole are mentioned.

The molecular weight of the reinforcing polymer (A>) is usually such that the intrinsic viscosity, which is a measure of molecular weight, is 1 or more, preferably 2 or more.

Matori used in the present invention, Tux polymer (B)
are dissolved in the same solvent as the reinforcing polymer (A), and include nylon 6, nylon 66, nylon 610. Nylon 12. Aliphatic polyamides such as nylon 11; aromatic polyamides such as polyhexamethylene isophthalamide; flexible aromatic polyamides with flexible groups such as ether groups; polyester: polycarbonate; polyvinyl acetate; borisulfone; polyethersulfone : Polyether imide, polyether ketone, polyphenylene sulfide, etc.

The common solvent may be any solvent as long as it dissolves the constituent polymers, and examples thereof include acidic solvents such as concentrated sulfuric acid and methanesulfonic acid. These may be mixed and used as appropriate.

These 171 media must contain 1% or more of a coagulant component. It is also not preferable to contain too much, and the content is usually 8% or less.

As the coagulant, a mixed aqueous solution of water and a solvent using water is preferable, and in this case, the component of the coagulant is water.

By including the coagulant component in advance in the polymer composite solution before coagulation, it is possible to form a uniform film after coagulation even if it is a thick film.

Generally, in the present invention, it is possible to further exhibit its effects by combining it with a phase change transient film forming method.

That is, when a polymer solution that initially has optical anisotropy at room temperature is heated, those in an appropriate polymer concentration range transition to optical isotropy in a temperature range of 50 to 90°C. If the polymer solution is placed in the temperature atmosphere from the solution in this state, when immersed in a coagulation liquid having a temperature that makes it optically anisotropic, the polymer solution will change from isotropic to anisotropic phase. It solidifies in a transient state, making it possible to produce molded products with excellent mechanical properties.

In the wood removal method, if a coagulant with the same components is included, the phase transition temperature will be lowered, and the polymer concentration can be further increased by the lowered amount, which further improves the ability to obtain good molded products. It makes it possible.

Another effect of containing the same component as the coagulant in the polymer solution is that the solution viscosity of the polymer solution is significantly reduced. By reducing the viscosity of the solution, the fluidity of the solution during film formation becomes stable, and furthermore, it becomes possible to increase the polymer concentration.

Due to these two effects, it is possible to obtain a molded product with excellent performance by forming a film from a polymer composite solution containing a coagulant component.

As a film forming method, the polymer solution extruded from a T-die or the like may be directly immersed in a coagulation bath, or the drum may be cast on a drum and then immersed in the coagulation bath. The solidified unstretched film needs to be neutralized with ammonia or sodium hydroxide, especially in the case of an acid solvent system, after sufficiently removing the remaining solution.

The dried film is then subjected to a normal stretching operation used to stretch films, etc., to form a highly modulus film.

The ratio of reinforcing polymer (A) and matrix polymer (B) used in the present invention is A/A+B of 5 to 45%.
It is good that it is within the range of . If the reinforcing polymer (A) is less than 5%, the reinforcing effect will be small, and if it exceeds 45%,
The orientation of the reinforcing polymer (A) deteriorates and the features of the present invention cannot be expressed.

The intrinsic viscosity used in the present invention refers to the amount of reinforcing polymer (A) dissolved in 100% sulfuric acid, methanesulfonic acid, or chlorosulfonic acid to a concentration of 0.2 g/100 cc, and then dissolved at 30°C in a conventional manner. The obtained ηinh
It is. When the reinforcing polymer (A) is dissolved in any of the above solvents, the lowest value among them is taken as the intrinsic viscosity of the reinforcing polymer (A>).

The effects of the present invention will be illustrated below with examples, and the percentages in the examples are based on weight unless otherwise specified. fiber·
The mechanical properties of the film were determined using a sample length of 4 (J per minute)
% elongation rate.

Examples 1-3. Comparative Example 1 As a reinforcing polymer (A), poly-p-phenylenebenzothiazole (abbreviated as PPBT) was polymerized according to a conventional method,
A product with an intrinsic viscosity of 4.1 in methanesulfonic acid solvent was obtained.

Matrix polymer (B) was prepared by adding 3,4'-diaminodiphenyl ether (50 mol%) and phenylenediamine (50 mol%) to N-methylpyrrolidone at a concentration of 6% under a dry nitrogen atmosphere. After cooling to 5°C, terephthalic acid dichloride powder (100 mol%) was immediately added to the solution while stirring vigorously, a polymerization reaction was carried out at 35°C for 1 hour, and this was precipitated with water. It was obtained by neutralizing it. Below, the polymer is PP0
It is abbreviated as T50. ηinh of P POT -50 was 3.6 in sulfuric acid solvent. PPBT and PP0T-50 were dissolved in methanesulfonic acid at a component ratio of 30/70. The initial moisture content of methanesulfonic acid is 0.4.
%, and by adding water to this, the moisture content in methanesulfonic acid is 1.5. 2.5. 3.5. Created one with 4.5%. The total polymer concentration was adjusted to 6.6%. The temperature at which the water content transitions from an anisotropic phase to an isotropic phase (phase transition temperature) of 0.4% was 98°C;
%, 2.5%, 3.5%, and 4.5%, the phase transition temperature decreased to 83°C, 78°C, 72°C, and 65°C. Also, the solution viscosity was 110,000 voids at a moisture content of 0.4%, but 7,500 to 500 at a moisture content of 1.5 to 4.5%.
It was observed that the viscosity decreased significantly to 0 voids.

The polymer solution was forced into a plunger, heated by a T-die according to the moisture content, and extruded into a coagulation bath through an air layer. The first coagulation bath was a 60% aqueous solution of methanesulfonic acid at 45°C, and the second reheating bath was a 930% aqueous solution of methanesulfonic acid at 30°C.

The coagulated film was thoroughly washed with water, neutralized with an aqueous sodium hydroxide solution, and then roughly washed with water for 24 hours. The film was placed in a fixed frame, air-dried, and then stretched at a temperature of 400°C with a stretching ratio equal to the maximum stretching ratio multiplied by 0.8 to obtain a uniaxially oriented film. As shown in Table 1, it is recognized that the tape performance is improved by including 1.0% or more of water as a coagulant component in the solution in advance.

Film forming conditions and mechanical properties of PPBT/PP0T-50 (30/70) tape

Claims (1)

[Claims] 1. A polymer solution mainly containing a reinforcing polymer (A) consisting of a polyazole having a substantially rod-shaped skeleton, a matrix polymer (B) having fusion properties, and a solvent (C) is coagulated. A method for producing a polymer composite comprising introducing the polymer into a bath and forming a film, characterized in that the polymer solution contains at least 1% or more of a component constituting a coagulant. Method of manufacturing the complex. 2. The method for producing a polymer composite according to claim 1, wherein the polymer solution contains 8% or less of a component constituting a coagulant.