JPH0259330A - Manufacture of peek resin pipe - Google Patents

Abstract

PURPOSE:To manufacture a crystallized PEEK resin pipe by cooling quickly a PEEK resin pipe material extruded from a die at the sizing part, after that, supplying it to the heating part, and reheating, and then cooling gradually, the molded and cured PEEK resin pipe up to a degree not being deformed. CONSTITUTION:The pipe molding material 3 of heated molten PEEK resin is extruded from the die 2 of an extruding mold 1, and it is introduced into a sizing part 4. The pipe molding material 3 is in a non-crystallized condition, namely, shows brown tint. The PEEK pipe material 3 introduced therein moves in close contact with the inner diameter wall surface of the sizing part 4, and as cooled and cured, a two colored pipe consisting of brown part by a non- crystallized layer 6 in its outer surface and gray part by a crystallized layer in its inner part. Next, the PEEK resin pipe 5 is introduced into a heating part 7, and it is preferably reheated by means of a far infrared ray heater. Thus, since the non-crystallized layer 6 of outer surface of the PEEK resin pipe 5 is turned into a crystallized condition, namely, a grey tint, a gray PEEK resin pipe crystallized entirely can be obtained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to PEEK (polyether ether ketone)
This invention relates to a method for manufacturing resin pipes.

[Conventional technology and its problems]

PEEK resin pipes have excellent physical properties such as heat resistance, chemical resistance, and abrasion resistance, and because they have a small coefficient of linear expansion, they are less affected by temperature changes than other resin pipes, and there is extremely little elution of impurities. thing.

Therefore, it is desired to be used as a pipe for transferring warm ultrapure water in the production of VLSI devices.

Although it is a high-performance pipe like this, it is made of PEE, which is the material.
In extrusion molding of K resin, PVC is used due to its low viscosity.
It had poor formability compared to other materials, and it was difficult to form a pipe with a stable shape.

When PEEK resin is heated and molten, it is in an amorphous state and its color is brownish-brown, but when it is gradually cooled and slowly passed through a temperature range where it crystallizes, it becomes a crystalline state and its color becomes gray.

Since the crystalline state is physically better and more stable, and there is no problem when joining pipes, which will be described later, a crystallized gray color is required as a product.

However, in extrusion molding of PEEK resin pipes, moldability is poor due to low viscosity, so PEEK extruded from a die has poor formability.
When forming and solidifying the EEK resin pipe material into a predetermined standard shape in the sizing section, it is gradually cooled and solidified, that is, in order to crystallize the PEEK resin extruded in an amorphous state, Sizing while cooling is accompanied by technical difficulties, and has the disadvantage of not increasing productivity and increasing costs.

Note that if the PEEK resin extruded in an amorphous state is rapidly cooled and solidified in the sizing section, the moldability of the pipe becomes easy. In this case, the surface of the PEEK resin introduced into the sizing part is cooled and solidified while remaining amorphous, and its color is brownish. However, the product cannot be used in this state.

This is because heat welding is used when joining pipes,
The welded part is once heated, and when it is gradually cooled in the air, it changes to a crystallized state, and the color of this welded part changes from brown to gray, making it unsightly and reducing the product value. caused by.

[Means for resolving conflicts]

Therefore, the present invention is based on the above! In order to solve this problem, the PEEK resin pipe material is heated and melted in an extrusion molding machine and extruded from a die, and then rapidly cooled in the sizing section.
After being molded and solidified into a pipe with an amorphous layer remaining at least on the outer surface, the molded and solidified PEEK resin pipe is then fed to a heating section and reheated to the extent that the shape of the pipe is not deformed. A method of manufacturing a crystallized PEEK resin pipe is practiced by gradually cooling the amorphous layer to change the amorphous state from an amorphous state to a crystalline state.

〔Example〕

A pipe molding material 3 of PEEK resin in a heated and molten state is extruded from a die 2 of an extrusion molding machine 1 and introduced into a sizing section 4. , the pipe forming material 3 is in an amorphous state, that is, it is brown in color. This pipe forming material 3 is quickly introduced into the sizing section 4, where it is rapidly cooled and solidified into a pipe shape with predetermined standard dimensions. Sizing part 4
It consists of a jacket in which cooling water circulates, and a core with an inner diameter that matches the outer shape of the pipe.

Also equipped with a vacuum suction device, the introduced PEEK resin pipe material 3 moves while closely contacting the inner diameter wall surface of the sizing section 4, and is cooled and solidified.

Since the PEEK resin pipe 5 pulled out from the sizing section 4 is rapidly cooled and solidified, at least its outer surface remains in an amorphous state, and an amorphous layer 6 is formed thereon.

The color of the amorphous layer 6 is brownish brown.

Although it depends on the wall thickness of the pipe, rapid cooling in the sizing section 4 affects only the outer surface of the pipe forming material 3, and even after the outer surface has cooled and solidified to the extent that the shape does not collapse, the inside remains. It is affected by the latent heat when it is extruded from an extruder and slowly cools down to a crystalline state. Therefore, a two-color pipe is formed, the outer surface of which is a brownish-brown part due to the amorphous layer 6, and the inside of which is a gray part due to a crystalline layer.

Next, the PEEK resin pipe 5 is introduced into the heating section 7 and reheated, preferably with a far-infrared heater. The heating temperature is such that it does not change the shape of the PEEK resin pipe 5.
For example, it is sufficient to pass 1ffi through a furnace at about 200°C. As mentioned above, since only the outer surface of the PEEK resin pipe is in an amorphous state due to rapid cooling in the sizing section 4, the reheating temperature at this time only increases the surface temperature, and there is a risk that the shape of the pipe may be thermally deformed. Not at all.

As a means for reheating, it is preferable to incorporate the heating section 7 into the extrusion molding line as in this embodiment, as it allows continuous production, which improves productivity and leads to cost reduction. There is no problem even if it is a separate process.

By reheating in the heating section 7 in this way,
By changing the amorphous N6 on the outer surface of the PEEK resin pipe 5 from an amorphous state to a crystalline state, that is, from brown to gray, the entire gray PE is crystallized.
I was able to obtain an EK resin pipe.

The molded PEEK resin pipes were then joined by heat welding, but the entire pipe was gray and there was no change in color at the joint.

〔Effect of the invention〕

The manufacturing method of the present invention not only has the advantage of being able to efficiently manufacture PEEK resin pipes with low viscosity and extremely poor extrusion moldability, but also takes into account post-processing to prevent color change at the joint when joining the pipes. It has the characteristics of being able to manufacture PEEK resin pipes with high product value.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view of a PEEK resin pipe manufacturing line according to the first invention, and FIG. 2 is a sectional view taken along the line A-A in FIG. ■...Extrusion molding machine 2...Die 3...PEEK resin bi 4...Sizing section 5...PEEK resin pipe molding material professional...Amorphous layer 7...Heating section

Claims (1)

[Claims] PEE heated and melted by an extruder and extruded from a die
The K resin pipe material is introduced into the sizing section and rapidly cooled to form and solidify into a pipe with an amorphous layer remaining at least only on the outer surface.Then, it is supplied to the heating section and the molded and solidified PEEK resin is A crystallized PEEK resin pipe characterized in that the amorphous layer is changed from an amorphous state to a crystalline state by reheating the pipe to an extent that the shape of the pipe is not deformed and gradually cooling the pipe. Production method.