JPH01207319A - Production of high-strength molded article of liquid crystal resin - Google Patents

Abstract

PURPOSE:To obtain the title molded product for reinforcing material of optical fiber, etc., in a low cost, by adding a specific organic phosphorus compound to a molded product of a liquid crystalline polyarylate resin containing mesogen group in main chain, etc., and carrying out a solid-state polymerization at a temperature below the liquid crystal forming temperature of the resin. CONSTITUTION:A molded product of liquid crystalline polyarylate or polyester amide resin containing mesogen group expressed by formula I (X and Y are terminal substituting groups such as alkyl, alkoxy or cyano; A-B is a unit such as a formula -CH=N or a formula -N=N-) in the main chain is mixed with at least one of organic phosphorus compound expressed by formula Il (R1 is hydrocarbon; M1 is alkali metal; M2 is alkali metal, H, hydrocarbon or oxygen- containing hydrocarbon), formula III or formula IV (R2 is hydrocarbon; n is integer greater than 1) and subjected to a solid-state polymerization at a temperature above (the liquid crystal forming temperature of the liquid crystalline resin -50) deg.C to afford the aimed molded resin product.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for producing a high-strength liquid crystal resin molded article. More specifically, the present invention relates to a method for producing a liquid crystal resin molded product having high strength and high heat resistance.

[Conventional technology]

In recent years, highly functional resins have begun to be widely used.

Typical examples are liquid crystal forming polymers including aramids such as Kevlar. But such aramid.

The drawback was that it could not be melt-molded.

In contrast, so-called thermoplastic liquid crystal polymers have the great advantage of being melt moldable.

However, it was only through solid phase polymerization after melt molding that it became a polymer with high strength and high heat resistance. For this reason, in order to obtain a high-strength liquid crystal resin molded product, long-term heat treatment is essential, and as a result, the cost is currently significantly high.

This background was a major reason why thermoplastic liquid crystal resins, which have many characteristics, were not widely expanded.

In order to eliminate such drawbacks, Japanese Patent Application Laid-Open No. 17212/1983 discloses a technique in which the long-term heat treatment after spinning is eliminated by polymerizing the polymer in the final step of spinning. There is. However, this method has a major drawback: (1) process control is complicated; Further, the disadvantage (1) that the melt viscosity becomes high at the spinning discharge section cannot be eliminated.

There was a big drawback.

Also, in US Pat. No. 4,424.184.

A method is described in which an inorganic alkali metal salt is applied to thermoplastic liquid crystal resin fibers and then heat treated. However, such a method is less effective in terms of shortening the heat treatment time.

In order to eliminate such drawbacks, JP-A No. 61-289178 describes that one polymerization time can be shortened by using an inorganic alkali metal salt and an organic activator in combination.

However, this method has the disadvantage that using different materials in combination is complicated in terms of process.

[Problem to be solved by the invention]

An object of the present invention is to stably improve the strength of a liquid crystal resin molded product in a short period of time and at low cost.

[Means to solve the problem]

In view of this current situation, the inventors of the present invention have conducted extensive studies without being bound by conventional research concepts.

We have arrived at the present invention.

In order to solve the above problems, the present invention has the following configuration.

That is, fil A liquid crystal polyarylate or polyesteramide resin molded product having a mesogen group of the following formula 1 in the main chain is provided with at least one organic phosphorus compound represented by the following formula ) A method for producing a high-strength liquid crystal resin molded product, which is characterized by solid-state polymerization at a temperature of at least 100°F.

Here, X and Y represent terminal substituents such as alkyl, alkoxy, and cyano groups. Also, A-B.

The following units are shown.

Here, R1 and R2 are hydrocarbons, Ml is alkali gold fE
, M2 indicates any of the following.

■Alkali metal, ■Hydrogen, ■Hydrocarbon, ■Oxygenated hydrocarbon Note that n represents an integer of 1 or more.

(2) The method for producing a high-strength liquid crystal resin molded product according to claim 1, wherein the liquid crystal polyarylate or polyesteramide resin molded product has a specific surface area of 0.29 rrf/g or more.

(3) The form of the liquid crystal resin molded product is fiber or film 1
Claim 1. It is a species. Or the method for producing a high-strength liquid crystal resin molded product according to 2.

(4) The method for producing a high-strength liquid crystal resin molded product according to claims 1 to 3, wherein an organic phosphorus compound is applied and microwave heating is used during drying.

This will be explained in more detail below.

According to the present invention, it is completely surprising that a high-strength, heat-resistant liquid crystal resin molded product can be produced at low cost.

The constituent polymer of the liquid crystal resin molding that can be used in the present invention is a polymer having a mesogen group in the main chain.

That is.

The following mesogenic groups are liquid crystal polyarylates or polyesteramides in the main chain.

Here, X and Y represent terminal substituents such as alkyl, alkoxy, and cyano groups. Also, A-B.

The following units are shown.

There are various kinds of polymers having such mesogen groups, and they can be broadly classified into those made of polyarylate and those made of aromatic polyester amide.

There are various types of materials made of polyarylate, and conventionally known materials can be used.

It is not particularly limited. Particularly preferred are polymers mainly consisting of the following structural units. That is, here, X and Y each independently represent hydrogen, halogen, or an alkyl group having 4 or less carbon atoms.

Here, X represents hydrogen, halogen, or an alkyl group having 4 or less carbon atoms.

Also, ma from dicarboxylic acid! It will be done! The structural units are: Here, X represents hydrogen, halogen, or an alkyl group having 4 or less carbon atoms.

Furthermore, as a structural unit derived from hydroxycarboxylic acid; Here, X represents hydrogen, halogen, or an alkyl group having 4 or less carbon atoms.

Second, it is also effective to introduce a primary structural unit into the liquid crystal resin of the present invention in order to adjust the melt viscosity and melting point. That is, it is also effective to further introduce a structural unit represented by the following formula. nil (where X is 0.
C) I2. , C(C)lB')2. 1, which can rotate relatively freely between aromatic rings such as ), which represents SO2
Examples include a 1.1N motorcycle, or a 1NN motorcycle induced by an aliphatic diol or aliphatic dicarboxylic acid (where m and n are numbers from 2 to 10).

Particularly preferable liquid crystal polyarylate resins include those having the following structural formula. That is, here, Σn1=100 in each structural formula. Particularly preferred is that ni of each structural formula is 4 or more. Moreover, various substituents including halogen etc. may be added to each formula.

These materials have high melt moldability, high strength and high elastic modulus, and are particularly preferred.

In addition, there are various types of liquid crystal 111 resins made of liquid crystal polyesteramide, and conventionally known ones can be used, and there are no particular limitations.

Particularly preferred are the following. That is, the structural unit derived from aminophenol is represented by the following formula.

In addition, as structural units derived from aromatic dicarboxylic acids, in addition to those listed above in the section on liquid crystal polydegradation rate, those represented by the following formulas are particularly preferred.

Here, AR is at least one aromatic ring having an alkyl or alkoxy substituent having up to 4 carbon atoms, the chain extensions of which are coaxial or parallel and oriented in opposite aromatic directions.

Examples of liquid crystal polyesteramide include those having the following structural formula. That is, here, AR is at least one aromatic ring having an alkyl or alkoxy substituent having 4 or less carbon atoms, and whose chain extension bonds are coaxial or parallel and point in opposite directions.

X Here, X represents hydrogen, halogen, or an alkyl group having 4 or less carbon atoms.

Here, X represents hydrogen, halogen, or an alkyl group having 4 or less carbon atoms.

Here, Σn1=100 in each equation.

In each structural formula, ni is preferably 15 or more, and in each structural formula, some of the hydrogens may be added with various substituents, including halogen, or crosslinked, It goes without saying that a part of it may be denatured. Such materials are preferred because they have high strength and chemical resistance.

In the present invention, such polymers are made into various molded products.

The molded product of the present invention is not particularly limited, and may include fibers such as ultrafine fibers, fibrillar fibers, hollow fibers, porous fibers, porous hollow fibers 9, and films.

Porous films, three-dimensional molded rings, fine particles, etc. are all included. Note that these may be used alone or in combination, and the form thereof should be determined depending on the purpose and use.

In particular, when forming a liquid crystal resin molded product with high strength, it is preferable to increase the molecular orientation of the liquid crystal resin molded product. That is, it is preferable to apply an appropriate shearing force during melt molding and form the material into fibers, films, etc., because it is particularly easy to obtain high strength.

In addition, especially when a high-strength liquid crystal resin molded product is to be obtained by heat treatment for a short time, it is preferable to increase the surface area of the liquid crystal resin molded product. /g or more, more preferably 0.4 m/g or more.By widening the surface area in this way, a liquid crystal resin molded product with surprisingly high strength can be obtained in a short time.Also, the absolute value of the strength ′ will also be higher than those with a narrow surface area.

Next, in the present invention, at least 1 yi is added to the liquid crystal resin molded product from among those shown below, and R
1, R2 represents a hydrocarbon, Ml represents an alkali metal, and M2 represents any of the following.

■Alkali metal, ■Hydrogen, ■Hydrocarbon, O-oxygen hydrocarbon. Note that n represents an integer of 1 or more.

Particularly preferable R1 is as follows. That is, A, an alkyl group having 4 to 30 carbon atoms, B, an alkylphenyl group having 7 or more carbon atoms, C0, a phenyl group having 6 or more carbon atoms, and R2 is a hydrocarbon having 5 or less carbon atoms.

Particularly preferred is carbon number 2. or 3 is preferred. That is, the moiety that binds to phosphorus is an ethylene oxide group or a propylene oxide group. Since such a material is easily dissolved or dispersed in water, it is easy to uniformly apply it to a liquid crystal resin molded product.

Furthermore, as Ml, sodium and potassium are particularly preferable.

Particularly preferable examples of M2 include alkali metals such as sodium and potassium, hydrogen, hydrocarbons, and oxygen-containing hydrocarbons such as ethylene oxide adducts.

As a matter of course, in the present invention, it is essential to add such an organic compound to the liquid crystal resin molded product, so other substances 1, such as dispersants for these compounds, etc., as well as iodine It does not matter if potassium oxide, salt, etc. are combined.

Next, regarding the amount of the organic phosphorus compound deposited, it is difficult to say in general since it varies greatly depending on the type and shape of the liquid crystal (H resin molded product), but it is preferably 0.05 wt%.
(hereinafter referred to as wt%) or more is preferable.

Particularly preferred is 0.1 to 10 wt%. If the amount of adhesion is less than 0.05 wt%, the effect tends to be low. On the other hand, even if the content exceeds 10 wt%, there is no particular problem as a product obtained, but handling is troublesome. Further, such organic phosphorus compounds remaining in the liquid crystal resin molding often cause unexpected problems such as inhibiting the adhesion between the liquid crystal resin molding and other objects.

The method of applying these organic phosphorus compounds is not particularly limited (e.g., dipping method, coating method, etc.).

Conventionally known methods such as a spray method can be widely used.

Some of these organic phosphorus compounds are solid at room temperature, so they may be applied in the form of fine particles, but a particularly preferred method is to dissolve and/or disperse the organic phosphorus compounds in water or a solvent, etc. It is to be granted by the method typified by. By doing so, the organic phosphorus compound is uniformly applied to the liquid crystal resin molded product.

Moreover, it has the advantage of being easily imparted.

When the phosphorus compound is applied to the liquid crystal resin molded product in liquid form, it is dried. There are no particular problems with drying using the conventional method, but
Microwave heating is a particularly effective method when uniform application of the organic phosphorus compound is required.

Furthermore, when the organic phosphorus compound migrates by drying, it is particularly preferable to add a substance that causes clouding due to heat, a thickener, etc. to the liquid of the organic phosphorus compound.

Next, the liquid crystal resin molded product to which the organic phosphorus compound has been applied is subjected to solid phase polymerization. Solid state polymerization is at high temperatures.

That is, under a vacuum at a temperature of (liquid crystal formation temperature -50°C) or higher of the liquid crystal resin, in an inert gas stream such as a nitrogen stream, or the like.

Conventionally known methods can be applied, and there are no particular limitations. Note that as the solid phase polymerization of the liquid crystal resin progresses, its melting point also increases, so it goes without saying that the solid phase polymerization can be carried out at a temperature higher than the original melting point of the liquid crystal resin.

Solid phase polymerization may be carried out at a constant temperature.

It is also particularly preferable to raise the temperature stepwise.

Further, the heating method is not particularly limited, but using microwave heating or the like is also an efficient method and is particularly preferred.

The apparatus and form of solid phase polymerization are also not particularly limited. If the molded product is a fiber, solid phase polymerization may be performed while it is wound around a pirn. It is also possible to carry out solid phase polymerization in the form of a fabric. However, it is important to sufficiently control the temperature and atmosphere so that the polymerization proceeds uniformly.

In particular, when solid-phase polymerization is performed with fibers wound around a pirn, etc., there may be a difference in the degree of polymerization between the inner and outer layers of the pirn. It is also particularly preferable that the solid phase polymerization proceed easily.

The preferred value for the molecular weight of TLCP after solid phase m-combination is T
The number average molecular weight is preferably 10,000 or more, which varies greatly depending on the type and use of LCP, which is difficult to say for boat fishing. In particular, when used in final products such as fibers and films, it is preferably 20,000 or more. More preferably 3
More than 10,000.

Particularly preferred is 50,000 or more. Such a TLCP has high strength and high elongation, which is extremely preferable.

The present invention will be explained in more detail with reference to Examples below. It goes without saying that the present invention is not limited to these Examples.

(Example〕 Example 1 As shown below, everything from liquid crystal resin to fibers was made.

There were no particular problems with the process.

A. Preparation of liquid crystal polyarylate A liquid crystal polymer similar to 9 so-called VECTRA was experimentally produced according to the method disclosed in Japanese Patent Application Laid-Open No. 54-77691.

The liquid crystal start temperature on the main island is approximately 250°C.

The melting point was approximately 280°C. Also, the Tg point is about 120
It was ℃.

B゛, Silk reeling A prototype liquid crystal resin fiber was produced using the following method.

There were no problems with silk reeling.

■ Spinning temperature - 300°C ■ Spinning speed - 100 m/min ■ Stretching ratio - not stretched ■ R fiber denier of the obtained fiber (hereinafter referred to as d) =
7d C0 Characteristics of the obtained liquid crystal resin fiber ■Strength - 8.2 g/d ■Elongation = 2.3% ■Modulus of elasticity - 440 g/d D, type and method of application of organic phosphorus compound ■Type nilauryl phosphate potassium ■ Application method: The above organic phosphorus compound was dissolved in water at Swt%, and the above liquid crystal resin fiber was immersed in the aqueous solution of the organic phosphorus compound to apply it. The amount applied was about 3 wt%. In addition,
The aqueous solution of the organic phosphorus compound was stable, and the organic phosphorus compound liquid could be applied in an extremely stable process.

Drying was performed using hot air drying.

E. Solid phase polymerization: Continuous two-stage treatment as described below. Note that no fusion of m-fibers was observed.

■Temperature: 1st stage = 250°C x 30 minutes 2nd stage -290°C x 30 minutes ■Atmosphere: In nitrogen stream. ! ili fibers are treated in a relaxed state.
Physical properties of the obtained liquid crystal resin fiber ■Strength = 20.5 g/d ■Elongation - 3.8% ■Modulus of elasticity - 470 g/d ■Number average molecule Et of the obtained fiber - 5,50,000, that is, high A strong fiber was obtained. This fiber also has high chemical resistance and can be used as is for various purposes.

Comparative Example 1 Obtained by spinning in Example 1. Solid state polymerization was carried out in the same manner as in Example 1 without adding anything to the untreated fibers.

Although the fibers maintained their shape, fusion occurred between the fibers, making it impossible to measure their physical properties properly.

Example 2 The spun yarn of Example 1 was wound around a pirn with many holes,
The sample was placed in a so-called cheese dyeing machine, and the organic phosphorus compound liquid of Example 1 was applied thereto. Afterwards, it was dried in a microwave oven.

There was no significant difference in the amount of organic phosphorus compounds deposited inside or outside the burn. The average coverage was 3.2 Wt%.

Next, this peirn was treated in the same manner as in the example process to obtain the following fibers.

■ Strength = 19.8 g/d ■ Elongation = 3.4% ■ Elastic modulus - 460 g/d ■ Number average molecular weight of the obtained fiber - 5,000,000, i.e. 0 fibers resulting in high strength fiber It also had high chemical resistance and could be used as is for various purposes.

Example 3 By the following method, 4! ! 8 fine liquid crystal resin fibers were spun. There were no particular problems in the process.

A. Spinning ■Spinning method - so-called polymer array method ■Sea component: polystyrene ■Island component: polymer of Example 1 ■Island/sea (weight ratio 150150 ■Number of islands = 36 ■Spinning temperature: 300°C ■Spinning Speed: 1000 m/min ■Stretching: None ■ Single fiber d of obtained polymer array fiber: 30 [phase] Removal of sea component: The obtained fiber was immersed in trichlene to melt and remove the sea component.Calculation The removal rate of the upper sea component is 100%.
Met.

B. Characteristics of the obtained rolled silk fiber ■Fineness: approx. 0.4d ■Specific surface area: approx. 0.4bo/g ■Strength: 11g/d ■Fineness = 2.4% ■Modulus of elasticity: 450g/d Application of C9 organic phosphorus compound and solid phase polymerization: Performed in the same manner as in Example 1.

D. Characteristics of the obtained fiber ■Strength - 26.3 g/d ■Elongation = 3.2% ■Modulus of elasticity = 800 g/d ■Number average molecular weight of the obtained fiber = 61,000, that is, ultra-high strength - Liquid crystal resin fibers with high elastic modulus were obtained. This fiber also has high chemical resistance and can be used as is for various purposes.

Comparative Example 2 The spun fiber of Example 1 was subjected to solid phase polymerization in a nitrogen stream at 250° C. for 50 hours without adding an organic phosphorus compound.

The obtained fibers had high strength as shown below, but
It had a rather low elastic modulus. In addition, various attempts were made to change the temperature in order to shorten the 2M coalescence time, but no particularly effective conditions were found.

■Strength-19.3g/d ■Elongation -3.9% ■Modulus of elasticity -402g/d Example 4 As shown below, everything from liquid crystal resin to fibers was made.

There were no particular problems with the process.

A. Preparation of liquid crystal polyester amide A liquid crystal polyester amide was prepared according to the method disclosed in Japanese Patent Publication No. 62-50496. That is, according to Example 1 of the publication, a liquid crystal polymer was prototyped using acetoxyacetanilide and butoxyterephthalic acid as raw materials.The liquid crystal initiation temperature of this product was approximately 200°C, and the melting point was approximately 290°C.
,Met.

B,! ! thread A prototype liquid crystal resin fiber was produced using the following method.

There were no particular problems with yarn reeling.

■Spinning temperature: 310℃ ■Spinning speed = 100 m/min ■Stretching ratio - without stretching ■Single fiber denier of the obtained fiber (hereinafter referred to as d) -
5d C1 Characteristics of the obtained liquid crystal resin fiber 0 Strength - 6.3 g/d ■ Elongation - 2.7% ■ Modulus of elasticity = 380 g/d D, type and method of application of organic phosphorus compound ■ Type Nilauryl bosphate potash (2) Application method: Application was performed in the same manner as in Example 1. The amount of adhesion is about 3
It was wt%. Note that the aqueous solution of the *ta phosphorus compound was stable, and the organic phosphorus compound liquid could be applied in an extremely stable process.

Drying was performed using hot air drying.

E, Solid phase m combination: Continuous two-stage treatment as described below. Note that no fusion of Ta fibers was observed.

■Temperature: 1st stage -200°C x 30 minutes 2nd stage -250°C x 30 minutes ■Atmosphere: In a nitrogen stream. The fibers are treated in a relaxed state E, and the physical properties of the obtained liquid crystal resin fiber ■ Strength - 17.5 g/d ■ Elongation = 3.9% ■ Elasticity = 460 g/d ■ Number average molecule of the obtained fiber 1i1 = 56,000, that is, high strength fibers were obtained. This fiber also has high chemical resistance.
It could be used as is for various purposes.

Comparative Example 3 Obtained by spinning in Example 4. Solid state polymerization was carried out in the same manner as in Example 4 without adding any unheated fibers.

Although the fibers maintained their shape, fusion occurred between the fibers, making it impossible to measure their physical properties properly.

Example 5 Ultrafine liquid crystal resin fibers were spun using the method described below. There were no particular problems in the process.

A. Spinning ■Spinning method 2 So-called polymer array method ■Sea component: polystyrene ■Island component: polymer of Example 4 ■Islands/sea (weight ratio): 50150 ■Number of islands: 36 ■Spinning temperature: 310°C ■Spinning speed: 1200 m/min ■Stretching: None ■Single fiber d of obtained polymer array fiber: 50 [phase] Removal of sea component: The obtained fiber was immersed in trichlene to melt and remove the sea component. . Calculated sea component removal rate is 100%
Met.

B. Characteristics of the obtained ultrafine fiber ■Fineness: approx. 0.6d ■Specific surface area: approx. 0.38rr? /g ■Strength: 10 g/d ■Elongation: 2.5% ■Elastic modulus: 410 g/d Application of C1 organic phosphorus compound and solid phase polymerization: The same procedure as in Example 1 was carried out.

D. Characteristics of the obtained fiber ■Strength - 21,5 g/d ■Elongation - 3,8% ■Modulus of elasticity - 670 g/d ■Number average molecular weight of the obtained fiber - 7,20,000, that is, ultra-high strength・The zero fibers from which liquid crystal resin fibers with high modulus of elasticity were obtained had high chemical resistance and could be used as is for various purposes.

〔Effect of the invention〕

By adopting the configuration of the present invention, the following great effects are brought about.

(1) Liquid crystal resin molded products with high strength and high elastic modulus can be easily obtained at low cost.

(2) Especially in ultrafine fibers, fibers made of liquid crystal resin with unprecedented high strength and high modulus of elasticity can be obtained.

(3) Since the solid phase polymerization rate is extremely fast, liquid crystal resin molded products can be produced at low cost.

(4) Since this liquid crystal resin molded product has high strength, the following uses can be considered.

■Various reinforcing materials: Reinforcing materials for optical fibers, tire cords, belts, helmets, etc. ■Ropes, friction materials, protective materials, sliding member materials ■Base materials for yarn mixed with carbon fiber, etc., glass fiber Base materials for mixed fiber yarns, printed base sheets, films, flint base films, etc.

Claims (4)

[Claims] (1) The following is applied to a liquid crystal polyarylate or polyesteramide resin molded product having a mesogen group of the following formula I in the main chain.
1. A method for producing a high-strength liquid crystal resin molded product, which comprises adding at least one organic phosphorus compound represented by formula II and solid-phase polymerizing the liquid crystal resin at a temperature of (liquid crystal formation temperature -50)° C. or higher. ▲There are mathematical formulas, chemical formulas, tables, etc.▼--(I) Here, X and Y represent terminal substituents such as alkyl, alkoxy, and cyano groups. Moreover, A-B indicates the following units. -CH=N--N=N-▲There are mathematical formulas, chemical formulas, tables, etc.▼▲There are mathematical formulas, chemical formulas, tables, etc.▼ {▲There are mathematical formulas, chemical formulas, tables, etc.▼ ▲There are mathematical formulas, chemical formulas, tables, etc. ▼ ▲There are mathematical formulas, chemical formulas, tables, etc.▼}--(II) Here, R_1 and R_2 are hydrocarbons, M1 is an alkali metal, and M2 is one of the following. [1] Alkali metal, [2] Hydrogen, [3] Hydrocarbon, [
4] Oxygen-containing hydrocarbon Note that n represents an integer of 1 or more. (2) The method for producing a high-strength liquid crystal resin molded product according to claim 1, wherein the liquid crystal polyarylate or polyesteramide resin molded product has a specific surface area of 0.29 m^2/g or more. (3) The form of the liquid crystal resin molded product is fiber or film 1
The method for producing a high-strength liquid crystal resin molded product according to claim 1 or 2, wherein the molded product is a seed. (4) The method for producing a high-strength liquid crystal resin molded product according to claims 1 to 3, wherein an organic phosphorus compound is applied and microwave heating is used during drying.