JPS6233870A - Reinforcing fiber material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to reinforcing fibrous materials.

More specifically, the present invention relates to a reinforcing fiber material having a metal coating on the surface of fibers made of thermoplastic resin.

(Prior Art) It has been common practice to mold a resin containing inorganic short fibers such as glass fiber to produce fiber-reinforced plastics (for example, Japanese Patent Laid-Open No. 57-34152). .

Furthermore, recently, proposals have been made to use nylon 6 and polyethylene terephthalate fibers, which have a low thermal shrinkage rate, as reinforcing materials for unsaturated polyester resins (Polymer Digest, April 1985 issue, pages 29-34).

(Problems to be Solved by the Invention) However, although reinforcing fibers made of thermoplastic resins have generally been improved, there still remains the problem that their reinforcing effects on tensile strength, impact strength, etc. are insufficient. Ta.

(Means for Solving the Problems) The present invention is made of a thermoplastic resin having metal coatings on two surfaces. Specific diameter and length/diameter ratio (hereinafter abbreviated as t/d)
This method succeeded in reinforcing the fibers by using short fibers that had a characteristic that had not been attempted before.

As stated above, the purpose of the present invention is to further increase the reinforcing effect of fibers made of thermoplastic resin.
An object of the present invention is to provide a reinforcing fiber material having a specific shape and having a metal coating on the surface of the two fibers.

The present inventors have conducted intensive research on such reinforcing fiber materials, and found that metal materials with high elastic modulus and high strength, and thermoplastic resin materials that are lightweight and easy to handle during molding and post-processing, etc. The above objectives were successfully achieved by effectively combining the strengths.

That is, the first invention of the present application is a fiber made of a thermoplastic resin, having a metal coating on two surfaces, and meeting the following conditions (
The object of the present invention is to provide a reinforcing fiber material that satisfies both a) and (b).

(a) diameter of 100μ or less; (b) length/diameter ratio of 100-10,000; ), (b), and also satisfies the following three conditions (c), (d), and (e).

(c) Strength 3.0 g/d or more (d) Elongation 10% to 50 inches (e) Dry heat shrinkage rate 10% or less (150°C) In the first and second inventions, the thermoplastic resin is polyester or nylon. More preferably, it is a thermoplastic resin selected from the following.

It is necessary for the reinforcing fiber material of the present invention to have a metal coating on the 9 surfaces, but at the same time, the above-mentioned (a), (
b) It is necessary to satisfy two conditions. If these conditions are not met, the reinforcing effect when used as a reinforcing material will be insufficient. That is, the diameter exceeds 100μ, or
/d must be trapped between 100 and 10,000.

It is no longer able to withstand the shear stress of the base material that occurs when internal shrinkage stress is applied, and virtually no reinforcing effect is achieved.

In addition, it is essential to simultaneously satisfy the three conditions (c) - (d) - (e) described above in order to achieve a reinforcing effect. If the strength is less than 3.097d, the impact strength will be poor, if the elongation is not between 10% and 50%, the moldability will be significantly impaired, or if the dry heat shrinkage rate exceeds 10cm, the molded product will be damaged. Inconveniences may arise in the reinforcing effect, such as cracks occurring during subsequent processing.

When it is intended to obtain a fiber reinforced plastic using the reinforcing fiber material of the present invention, it is appropriate that the amount added is usually about 3 to 50 kg by weight. Also.

It is also suitable to use it as a hybrid with glass fiber (with or without a metal coating on the surface).

The base material to be reinforced is suitable for making fiber-reinforced plastics using the reinforcing fiber material of the present invention.

Thermosetting resin whose temperature during heat curing is about 130°C or less,
For example, unsaturated polyester resins, diallyl phthalate resins, phenolic resins, and epoxy resins.

Examples include area resin and melamine resin.

Note that the diameter of the reinforcing fiber material (hereinafter abbreviated as d) in the present invention has a broad meaning including the case of a non-circular cross section, and is defined by a quadratic equation.

d=-π (Here, S indicates the cross-sectional area of the fiber, and π indicates the circumference.) The fiber matrix made of thermoplastic resin as used in the present invention includes:
General-purpose fiber matrix materials such as polyester, polyamide, polyolefin, and polyvinyl chloride can be used alone or in combination. Among them, polyester (polyethylene terephthalate and polybutylene terephthalate),
Common synthetic fibers such as polyamide (Silon 6 and Nylon 66) are preferred in terms of strength, durability, and ease of coating the surface with metal.

Electrolysis is also used to coat the fiber surface with metal.

Although there are various plating methods such as electroless plating and immersion methods, various vapor deposition methods such as vacuum and plasma methods, and various thermal spraying methods, it is appropriate to perform electroless plating, that is, so-called chemical plating.

An example of a method for producing a 18 ml reinforcing material is shown below.

For example, when polyester is used, it has an intrinsic viscosity of 0.60 to 1.20 when measured in an equal weight mixture of phenol and tetrachloroethane at 20°C. Preferably 0.75-1.0
Using 0 polyethylene terephthalate.

Spinning temperature 290-310℃, spinning speed 600-2,00
0 ml" is melt-spun from a spinneret with a 500-hole radius to obtain undrawn subtow of tens of thousands to millions of deniers. After being bundled, it is put into a drawing machine, and after being drawn, it is heat-set at an appropriate temperature and made into a book. After satisfying the conditions such as strength and elongation specified in the invention, a metal coating is formed on the surface of the long fibers by the method described above, and then cut to have the t/d specified in the invention. Is it made into short fibers?

Alternatively, a metal coating may be formed on the surface of the short fibers after cutting.

To perform chemical plating on the fiber surface, as mentioned above, depending on the material, it can be in the form of long fibers or short fibers.

For example, polyester fibers may be roughened using an alkaline solution, and polyamide fibers may be roughened using a chromic acid/sulfuric acid solution, then sensitized and activated, and treated with a chemical plating bath. The sensitization treatment is performed using an acidic solution of 1 to 10% by weight of stannous chloride in hydrochloric acid, and the activation treatment is performed using an aqueous solution of a palladium compound with a concentration of palladium atoms of approximately 0.1 to 2,000 ppm. It may be treated with a metal chemical plating bath of nickel, copper, cobalt, chromium, silver, etc. or a mixture thereof.

Further, from an economical point of view, it is preferable to use nickel or copper as the type of metal. Usually, it is most preferable to use a plating bath consisting of a nickel/hypophosphorous acid compound, which has a fast plating rate.

The reinforcing effect depends on the thickness and purity of the metal layer, but chemical plating can reduce the d of the entire reinforcing fiber material from 0.5 to 50.
Fibers coated with a metal layer having a thickness of 100 mm are preferably used as the reinforcing fiber material.

(Function) The reinforcing fiber material of the present invention has a metal coating on two surfaces and has a specific fiber shape, so even though the fiber matrix is a thermoplastic resin, the reinforcing fiber material When used as a material, it exhibits an extremely remarkable reinforcing effect.

(Examples) Hereinafter, the present invention will be specifically explained using Examples, but the present invention is not limited to these Examples.

The 1-strength elongation is measured in accordance with JIS-L-2511K, while the dry heat shrinkage rate is measured by freely shrinking in air at 150 ± 1°C without tension, and calculating the original length of the contracted length. It represents the ratio (4) to the

Example 1 Polyethylene terephthalate tow with an intrinsic viscosity of 0.95 (200,000 denier, single yarn diameter d is as shown in Table 1)
(Using a neutral detergent for normal degreasing, washing, and dispersion in water) A weight reduction treatment was performed with an aqueous solution of IJum.

Thereafter, it was sequentially treated with a dilute hydrochloric acid solution, a stannous chloride solution, and a palladium chloride solution, and immersed in a nickel/hypophosphite-based chemical plating bath to obtain a metal-coated polyester tow. d to obtain reinforcing short fibers. Table 1 shows the results of measuring the characteristics.

IJ in which the reinforcing polyester short fibers are added in an amount equivalent to 20 parts by weight to 100 parts by weight of vinyl ester resin, and benzoyl peroxide is blended as a curing catalyst.
The mix was cured at a curing temperature of 93°C.

A No. 1 dumbbell test piece for tensile testing specified in ASTM D 638 and an impact test piece specified in ASTM D256 were molded, and the properties of the molded products were evaluated.

Example 2 Same as Example 1 except that reinforcing short fibers with the characteristics shown in Table 1 were obtained by appropriately changing the intrinsic viscosity of polyethylene terephthalate, spinning/drawing conditions during production, heat setting conditions, etc. I went to

The results are shown in Table 1.

Example 3 Same as Example 1 except that nylon 6 tow with a concentration of 1.0 g/100 cc of 98 thiosulfuric acid and a relative viscosity of 3.60 measured at 30°C was used, and the weight was reduced with a sulfuric acid/chromic acid aqueous solution. The results are shown in Table 1.

Comparative Example 1 The same procedure as in Example 1 was carried out except that reinforcing short fibers having the characteristics shown in Table 2 were obtained by appropriately changing the spinning/drawing conditions or the cut length. The results are shown in Table 2.

Comparative Example 2 The same procedure as in Example 1 was carried out except that polyethylene terephthalate tow without a metal coating was used. The results are shown in Table 2.

Table 2 [Note] PET: Polyethylene terephthalate (effects of the invention) It can be seen that the reinforcing fiber material of the present invention has a very remarkable reinforcing effect when used as a reinforcing fiber material.

At the same time, the reinforcing fiber material of the present invention has gold 1-@ on the surface.
In addition to the effects of having a coating, it also has an antistatic effect and an electromagnetic shielding effect.

Claims (1)

[Scope of Claims] (1) A reinforcing fiber that is made of a thermoplastic resin, has a metal coating on its surface, and satisfies the following conditions (a) and (b) at the same time: material. The reinforcing fiber material according to claim 1, wherein (a) the diameter is 100 μm or less, (b) the length/diameter ratio is 100 to 10,000, and (2) the thermoplastic resin is polyester or nylon. (3) A fiber made of the thermoplastic resin of (1), having a metal coating on the surface, and meeting the following conditions (a), (b),
A reinforcing fiber material characterized by satisfying (c), (d), and (e) at the same time. (a) Diameter 100μ or less (b) Length/diameter ratio 100 to 10,000 (c) Strength 3.0 g/d or more (d) Elongation 10% to 50% (e) Dry heat shrinkage rate 10% or less (150°C) (4) The reinforcing fiber material according to claim 3, wherein the thermoplastic resin is polyester or nylon.