JPS60218610A - Reinforcing material made of aromatic polyamide fiber - Google Patents

Abstract

PURPOSE:To improve flexibility greatly and to make a bend with small curvature by using aromatic polyamide fiber as the principal material of the reinforcing material. CONSTITUTION:Four twisted ''Kevler'' fiber bundles are dipped in at least >=2 oligomers, and the ''Kevler'' fibers are squeezed between two rolls to remove excessive oligomers. Then, they are coated continuously with low-density PE under pressure by a 50P pressing machine to a 0.35mm. thickness to extrude a cord with a 1.5mm.phi external diameter. Then, electron beam irradiation is carried out by a 1MeV electron beam accelerator to a 20Mrad dosage to cure oligomers, forming the reinforcing material. The reinforcing material consists of aromatic polyamide fiber 10 containing a unsaturated compound and a resin layer 20.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a reinforcing material that is highly flexible, lightweight, and has high strength, and is suitable as a tension member.

<Prior Art> Conventionally, the reinforcing material used for tension members of optical cables and the like is generally so-called FRP, which is made by impregnating glass fiber with epoxy resin.

This is a rod made by punching and molding. However, the reinforcement of FRP mentioned above has poor flexibility, for example, in the case of a 1uφ rod,
If bent with a curvature of about 51, it will break. Furthermore, since it is heavy, there are problems such as an increase in the weight of the entire cable.

<Object of the invention> The present invention uses aromatic polyamide fibers instead of the FRPtC, and further improves the type of fibers to be impregnated.
The purpose of the present invention is to provide a reinforcing material that has high strength and is easy to manufacture.

<Structure of the Invention> The structure of the present invention that achieves the above object is that after impregnating aromatic polyamide fiber with a radiation-curable compound, it is further coated with a resin, and then the above-mentioned compound is cured by radiation irradiation. It is characterized by:

FIG. 1 shows a schematic cross-sectional structure of the reinforcing material according to the present invention. As shown in the figure, the central portion IO of the reinforcing material is made of an aromatic polyamide fiber bundle impregnated with a radiation-curable compound, and its outer periphery is coated with a resin layer 20.

The above-mentioned aromatic polyamide fiber is generally called Keppra fiber.

The bundle of Kepku fines is impregnated with a radiation-curable compound.

fIliJ Here, the above-mentioned radiation-curable compound is a monomer or low-weight compound having at least two or more unsaturated bonds, such as epoxy acrylate, urethane acrylate, nupyran acrylate, polybutadiene, etc., which can be cured by radiation irradiation. Refers to compounds that harden or resins that harden when exposed to radiation, such as epoxy resins.

In addition, radiation curing refers to electromagnetic waves such as electron beams and X-rays,
It refers to substances that are hardened by radiation in a broad sense, such as rays, β rays, and β rays. □Next, after impregnating with the above-mentioned radiation-curable compound, a thermoplastic resin is further coated.

Polyethylene (PK) is a thermoplastic resin.

EVA etc. are used.

After that, the unsaturated compound is cured by radiation irradiation,
Form the desired reinforcement.

A specific example of the above manufacturing process is shown in FIG.

As shown, a supply drum 1, an impregnating tank 2, an extrusion coating 7
The machine 3, the cooling tank 4, and the winding drum 5 are arranged in a row. Kepra fibers are wound in the supply drum 1, and the radiation-curable compound is stored in the impregnation tank 2.

Further, the extrusion coating machine 3 is supplied with a thermoplastic resin for coating the resin layer 20. The Kepra fiber 6 drawn out from the supply drum 1 is immersed in an impregnating bath 2 and impregnated with the radiation-curable compound. Next, the excess compound is removed by guide rollers 2a, and then the material is introduced into an extrusion coating machine 3.

The extrusion coating machine 3 extrudes and coats the outer periphery of the Kevlar fibers 6 with a thermoplastic resin. The coating is subsequently led to a cooling bath 4, during which it is irradiated with radiation to radiation-cure the compound therein and form the desired reinforcement.

The reinforcing material is wound up on a winding drum 5.

<Example> Example 1. 4 twisted 1420 denier (1000 fi 2 ment) Kevlar fiber bundles (outer diameter 0.8 mφ)
is immersed in an oligomer (Lipoxy VR-80 Showa Kobunshi ■) having at least two unsaturated bonds at an intramolecular pressure, and the Kevlar fibers are squeezed between two rolls to remove excess oligomer. , a 50P extruder was used to continuously extrude coat low-density PE to a thickness of 0.3 f) II, and the outer diameter was 1.
I extruded a code with a diameter of 5 mm. After that, in a separate process, IMe
Electron beam irradiation was performed using a V electron beam accelerator to give an absorbed dose of 20 Mrad, and the oligomer was cured to form a reinforcing material. The breaking strength of this reinforcing material is 78
A value higher than the breaking strength of 60 h/lsd of glass fin (-FRP Rondo) of the same size as 1rr- was obtained.

Example 2. Using Kepra fiber bundles of the same size as in Example 1,
The cord was impregnated with epoxy resin (7 Deca Ultraset AD7200 Asahi Denka Kogyo ■), and after removing the excess resin in the same manner as the first cord, it was coated with low density PE by extrusion to produce a cord with an outer diameter of 1.5 mm. Thereafter, as in the above process, 20 Mrad of electron beam was irradiated using an I MeV electron beam accelerator to form a reinforcing material.

The breaking strength of this reinforcing material was as high as 804/I-.

<Effect of the invention> The reinforcing material of the present invention described above has the following advantages.

(a) Since aromatic polyamide fibers are mainly used as the reinforcing material, it is much more flexible than conventional FRP irons and can be bent with a small curvature.

(b) Furthermore, the weight can be significantly reduced by approximately 1/2 compared to conventional FRP.

(c) Also, the strength per unit area is high.For example, while the conventional FRP rod has a breaking strength of 60'II/Id, the reinforcing material of the present invention has an improved breaking strength of 80'II/Id.

B) Furthermore, since the outer periphery is covered with a resin layer, the surface is smooth and has good wear resistance. In addition, it has the following advantages in terms of manufacturing process.

(a) Since the resin layer is coated after the impregnation step, the impregnation step and the radiation curing step can be separated.

If a resin layer is not provided, the unsaturated compound or epoxy resin is uncured, so rapid radiation curing must be performed immediately, and a dedicated line is required.

(b) Since the coating is performed with a resin layer, uncured resin etc. do not adhere to the guide rows 2, etc., making it possible to easily maintain the device and to stably manufacture high-quality products.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a reinforcing material according to the present invention, and FIG. 2 is a schematic diagram showing a manufacturing process of the reinforcing material according to the present invention. In the drawing, l...supply drum, 2...impregnation tank, 2m.
...Guide roller, 3.. Extrusion coating machine, 4.. Cooling tank 5.. Winding drum, 6.. Kevlar fIA fiber, 10.
・・Aromatic polyamide fiber impregnated with unsaturated compound, 20・・
・Resin layer. Patent Applicant Sumitomo Electric Industries Co., Ltd. Agent Patent Attorney Shibu Mitsuishi (and 1 other person) Figure 1 Figure 2

Claims (1)

[Claims] After impregnating aromatic polyamide fiber with a radiation-curable compound, Kj! 1. A reinforcing material made of aromatic polyamide fibers, characterized in that the fibers are coated with a resin, and then the above-mentioned compound is cured by irradiation with radiation.