JPH0476055A - Polymer composite and its preparation - Google Patents

Abstract

PURPOSE:To prepare a polymer composite giving a molded article having a high modulus by incorporating a specified amt. of a metal (compd.) into a polymer composite mainly comprising a specific reinforcing polymer and a fusible matrix polymer. CONSTITUTION:A metal (compd.) in an amt. of 1-3wt.% in terms of metal element is incorporated into a polymer composite mainly comprising a reinforcing polymer substantially consisting of a polyazole having a rodlike structure (e.g. a poly-p-phenylenebenzobisthiazole) and a fusible matrix polymer (e.g. a polyamideimide). The resulting composite gives a film, tape, or fiber having an improved modulus, and, when powdered or granulated, can be thermally press molded into an article with high heat resistance and modulus.

Description

[Detailed Description of the Invention] [Technical Field] Reinforced plastics have been regarded as important as load-bearing structural materials because of their dramatically improved physical properties, and various materials have been developed and put into practical use. The production of such composite materials requires complicated step-by-step operations such as arranging separately manufactured reinforcing fibers in one direction and further impregnating a matrix, which also includes a step in an autoclave. Requires.

The strength and durability of the composite material largely depend on the state of the interface between the reinforcing 11ffl and the matrix polymer. Since the fibers themselves are macroscopic at the interface between the two, any defects present there will propagate to the macroscopic level, leading 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 combination with various matrix polymers. Although studies have been carried out to increase the modulus, the resulting materials have drawbacks such as a low tensile modulus compared to the additivity value expected when the polymer component is sufficiently oriented.

In order to solve this problem, the present inventors used a polyazole polymer such as polyp-phenylenebenzobisthiazole as a reinforcing polymer, and developed a system using a flexible polymer as a 71-lix polymer. The present invention was arrived at as a result of intensive research into high modulus.

That is, the present invention is a polymer composite mainly consisting of a reinforcing polymer (A) consisting of a polyazole having a substantially rod-like skeleton and a matrix polymer (B) having fusibility, which is calculated as a metal element. This is a polymer composite characterized by having a metal content of 1 to 3 wt%.

Further, the present invention provides a method in which a polymer solution mainly containing a reinforcing polymer (A) consisting of a polyazole having a substantially rod-like skeleton and a matrix polymer (B) having a fusibility is passed through a die or an orifice into a coagulation bath. In the method for producing a polymer composite, which involves introducing the metal into
．． This is a method for producing a polymer composite characterized by containing 1% or more.

<Specific method for solving the problem> The reinforcing polymer (A) used in the present invention has the following formula [wherein x represents -S-, -O- or -N-,
Bonds (i) and (0) are bonds that further form an azole ring or a hydrocarbon ring, or a hydrogen atom is bonded to one of them and the other is a bond. Polyazole having a substantially rod-like skeleton having an azole skeleton represented by
, 207,407, among which are polyazoles such as poly-p-phenylenebenzobisthiazole, poly-p-phenylenebenzoxazole, and poly-p-phenylenebenzobisimidazole.

The reinforcing polymer (A>) usually has an intrinsic viscosity of 3 or more, preferably 5 or more, and particularly preferably 10 or more.

Matrix polymer (B) used in the present invention-C
are soluble 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; semi-aromatic polyamides such as polyhexamethylene isophthalamide;
Aromatic polyamides such as polymetaphenylene isophthalamide; flexible aromatic polyamides into which a flexible group such as an ether group is introduced; polyimide, polyamideimide, polyamide acid imide, polyamide imide acid, and the like.

The common solvent may be any solvent that can dissolve the constituent polymers, and examples thereof include acidic solvents such as concentrated sulfuric acid, methanesulfonic acid, chlorosulfonic acid, polyphosphoric acid, and 1 to lifluoroacetic acid. These may be mixed and used as appropriate. Further, in order to suppress hydrolysis of the dissolved polymer, an additive may be mixed in to minimize the amount of water in the solvent. For example, addition of fuming sulfuric acid, chlorosulfonic acid, etc. may be mentioned.

The stock solution for forming a polymer composite is a polymer solution in which a reinforcing polymer and a matrix polymer are dissolved in the above-mentioned common solvent.

The metal compound added to the polymer solution is LiO
H, NaOH, M(1(OH)2.

Ca(OH)2, Ba(OH)2. AM (
OH)3.

Ni(OH)2. Zn (OH)2. CI (
OH)2.

Fe 3 (OH) 2 , Fe 2 (OH) 3
Metal hydroxides such as A 2 (304) 3, N!
Examples include metal sulfur M salts such as 304 and the like.

When these are mixed with the stock solution for polymer complex formation, they react with the acid that is the solvent and are dissolved.

The amount of these metal compounds such as metal hydroxides added depends on the solubility of the solvent, but is 0.1 wt% with respect to the solvent.
It is preferable that the content is in the range of 4 wt% to 4 wt%.

If the amount of the metal compound added is 0.1% or less, the modulus of the metal compound in the polymer composite molded article is not sufficiently improved. For example, if the amount of metal hydroxide added exceeds 4%, the water produced by the reaction between the acid solvent and the metal hydroxide will reduce the solubility of the polymer components constituting the polymer composite, resulting in insufficient solvency. This makes it difficult to obtain a good molded product.

The metal compound such as metal hydroxide mixed into the stock solution for forming a polymer composite may be further added to the coagulation bath.

By adding metal hydroxide etc. to the coagulation bath,
It becomes easier to obtain good fibers, films, or particles.

Most of the amount of metal hydroxide, etc. contained in the polymer composite after solidification diffuses into the coagulation liquid, so the amount actually contained in the polymer composite is It will be less than 5%. When converted into metal elements, this amount is approximately 1 to 3 wt%.

A conventionally known method can be used to form a molded body of a polymer composite.

By changing the shape of the extrusion nozzle before contacting the coagulation bath, we can produce fibers and films.

A tape-like product is obtained, and when it is solidified under stirring with a mixer, a particulate or powder-like product is obtained.

When metal hydroxide etc. are added to the polymer composite stock solution,
The reason why the modulus of molded products improves is not clear, but when metal hydroxides are contained, the metal ions strengthen the interaction between both polymers, which leads to phase separation between the reinforcing polymer and the matrix polymer. It is presumed that this suppresses the progress and improves dispersibility.

18 = Therefore, after solidification is completed, both component polymers are generally below the glass transition temperature, so movement that would involve movement of the center of gravity is suppressed, so at that point, the presence of metal hydroxide, etc. Even if it becomes less than 0.4%, it will not be a factor that deteriorates the performance of the molded product. It is important that metal hydroxide etc. be present at the start of solidification.

The stock solution for forming a polymer composite is a polymer solution prepared by dissolving a reinforcing polymer and a matrix polymer in the above-mentioned common solvent and further adding a metal hydroxide. An even better molded product can be obtained by molding from an optically isotropic state or an apparently optically isotropic state.

The optically isotropic state or the apparent optically isotropic state can be evaluated by placing the sample under observation with a polarizing microscope having crossed Nicols.

If the polymer solution exhibits a dark field under crossed Nicol conditions, it is in an optically isotropic state. If it shows a bright field, it is a state of optical anisotropy.

Fibers and films formed from optically anisotropic solutions do not exhibit good mechanical properties.

The apparently optically isotropic state is a state in which the polymer solution retains its optical isotropy for a while even after cooling. This state will be defined as an apparently optically isotropic state.

When a polymer composite stock solution in these conditions is used, the components of the polymer can be more uniformly dispersed, and a better molded product can be obtained.

<Effect of the invention> The molded article obtained by the present invention is in the form of a film.

Tape-like and fiber-like products have improved modulus, making it easier for particles and
The powdered material is useful as a raw material for producing a highly heat-resistant, high-modulus molded product by hot-pressing it.

(Method for measuring intrinsic viscosity of polyazole) Polyazole was dissolved in a methanesulfonic acid solution, and the polymer concentration was 0.05. It is set to 0.2wt%. This solution is measured with an Ubbelod viscometer to determine ηSD/C, and this is extrapolated to zero concentration to determine the intrinsic viscosity ([η]).

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 measured at 1 min per minute for a sample length of 4 cm.
Measurements were made at an elongation rate of 0%.

Example 1 A polyphosphoric acid solution of poly-p-phenylenebenzobisthiazole was prepared as follows.

That is, 2-5-diamino-1-94-benzenedithiol hydrochloride 55,399 was collected under an argon gas atmosphere,
The mixture was added to a flask containing 438 g of polyphosphoric acid which had been thoroughly degassed, and stirring was continued at 60° C. for about 24 hours under an argon gas atmosphere to remove hydrogen chloride gas. Then, an equal amount of terephthalic acid was added, and the degassed polyphosphoric acid was added to
Add 60q and stir at 90-100°C for 5 hours, then raise the temperature to 150°C and stir for 12 hours, and then add 180q
Stir at ~200°C for 24 hours. Finally, the intrinsic viscosity is 21
A polyphosphoric acid solution of poly-p-phenylenebenzobisthiazole was obtained.

This was cooled with ice and stirred and precipitated in a mixer containing IC water to obtain fibrous poly-p-phenylenebenzobisthiazole polymer particles.

Amoco's polyamideimide (trade name: Torlon) was used as the matrix polymer.

Poly-p-phenylenebenzobisthiazole and polyamideimide were dissolved in methanesulfonic acid prepared by dissolving 1% of aluminum hydroxide in advance so that the component ratio was 30/70, and the total polymer concentration was 3%. Created.

The polymer solution exhibited isotropy at room temperature when observed under crossed Nicols.

The polymer solution was put into a plunger type extruder, and the linear velocity was 27 rL/m into the air from a nozzle (diameter 0.2 gate φ).
Discharged in. After passing through an air layer of 2 cm, it was immersed in a water coagulation bath with a humidity of 40°C, and wound up while changing the winding speed in the range of 2 m/min to 13TrL7 min. Thereafter, the film was washed with warm water and then stretched at 360°C.

The obtained yarn exhibited an elastic modulus as shown in Table 1, and this value showed an excellent elastic modulus compared to Comparative Example 1 in which AJ-(OH)3 was not added. In addition, the fiber has an AU metal equivalent of 1.7
It contained ~2.1%.

Comparative Example 1 Polymer was produced under the same conditions as in Example 1, except that instead of using methanesulfonic acid in which 1.5% of aluminum hydroxide was dissolved, a solvent consisting only of methanesulfonic acid was used.
Spinning of p-phenylenebenzobisthiazole/polyamideimide was performed.

The obtained filament quality is shown in Table 1.

It can be seen that the elastic modulus is lower than that of Example 1.

Example 2 In Example 1, instead of using methanesulfonic acid in which 1.5% of aluminum hydroxide was dissolved, methanesulfonic acid in which nickel hydroxide was dissolved was used as the solvent, but the rest was the same as in Example 1. Spinning was carried out under the following conditions. Table 1 shows the elastic modulus of the obtained 7j yarn. It is recognized that the elastic modulus is significantly improved compared to Comparative Example 1. The IN contained 2.1% in terms of Ni metal.

Example 3 In Example 1, the obtained poly〇-phenylenebenzobisthiazole and nylon 6 were added to methanesulfonic acid in which 1% AM(OH)3 was dissolved in a component ratio of 30/70, and the polymer was added. was dissolved to a total concentration of 4.1%. The polymer solution had a transition temperature of 46°C. 3 while cooling the polymer solution heated to 50°C.
Methanesulfonic acid 1 from an orifice at 5℃ using a semi-dry and semi-humid method.
Extruded into a 0% coagulation bath. Extrusion linear speed is 2m/n
++n, and the winding speed is 2.5 to 10 m/min.
changed within the range.

After washing with water and drying, it was further hot stretched at 360°C.

Table 2 shows the elastic modulus of the obtained yarn.

The elastic modulus was improved compared to the system without metal salt.

Comparative Example 3 Spinning was carried out in the same manner as in Example 3, except that methanesulfonic acid in which A and u(OH)3 were not dissolved was used.

As shown in Table 2, the elastic modulus of the obtained fiber was inferior to that of the system containing AM(OH)3.

Table 1 Elastic modulus of PPBT/PAI (30/70) fiber (GP
a) Table 2

Claims (1)

[Claims] 1. In a polymer composite mainly composed of a reinforcing polymer (A) consisting of a polyazole having a substantially rod-like skeleton and a matrix polymer (B) having fusion properties, the polymer composite is made of a metal element. Converted metal content is 1~3w
t%. 2. Introducing a polymer solution mainly containing a reinforcing polymer (A) consisting of a polyazole having a substantially rod-shaped skeleton and a matrix polymer (B) having fusion properties into a coagulation bath through a die or orifice. A method for producing a polymer composite comprising spinning or film forming, wherein the polymer solution contains 0.1 wt% or more of a metal and/or a metal compound. .