JPH0254775B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an apparatus for continuously tension-stretching a long polymeric material under pressure, and more specifically, to an apparatus for continuously stretching a long polymeric material under pressure. This invention relates to an apparatus for improving the physical properties of a long polymeric material by stretching it in a countercurrent direction to the moving direction of the pressurized fluid while applying pressure isotropically using a pressurized fluid. It is something.

Conventional technology Generally, polymeric materials such as polyacetal are
There is a tendency for physical properties to decrease as the stretching speed increases [Polymer, Vol. 19, Vol.
1338 pages]. Such a tendency was also observed in the continuous press-stretching apparatus for polymeric materials proposed by the present inventors (Japanese Patent Application No. 72029/1982). this is,
This is thought to be due to the fact that by increasing the stretching speed, heat control such as supply of heat to the polymeric material or removal of heat during stretching becomes insufficient, resulting in non-uniform temperature of the stretched material.
For example, in the device of the previous application, the moving direction of the pressurized fluid, which is also a heating medium if necessary, and the stretching direction of the polymeric material are the same, so if the stretching speed is increased, the stretching material and the heating medium are The transfer of heat becomes slow, and the temperature of the material becomes non-uniform, resulting in a decrease in physical properties. Of course, even in this apparatus, the above problem can be solved by increasing the flow rate of the pressurized fluid even more when the stretching speed is increased. However, it is not practically preferable to increase the flow rate of the pressurized fluid higher than the stretching speed.

Problems to be Solved by the Invention In view of the above circumstances, the present inventors have developed a practical continuous pressurization method for polymeric materials that can improve the physical properties even if the stretching speed of the polymeric material is increased. As a result of extensive research in order to provide a stretching device, we have found that while applying pressure isotropically using a pressurized fluid that is also a heating medium as necessary, in the direction of movement of the pressurized fluid,
The inventors have discovered that the objective can be achieved by stretching a polymeric material in the countercurrent direction, and have completed the present invention based on this knowledge.

Means for Solving the Problems In other words, the present invention provides a pressure-resistant container filled with a pressurized fluid in a substantially closed state and an elongated body of polymeric material that continuously moves through the container. In a continuous pressurized stretching device equipped with a stretching mechanism for applying stress, a pressurized fluid outlet is provided on the supply port side of the elongated polymeric material of the pressure-resistant container, and a pressurized fluid inlet port is provided on the outlet side of the elongated polymeric material body of the pressure-resistant container. are provided respectively, and both the supply port and the discharge port are provided with a gap formed between the elongated body passing through them, through which a small amount of pressurized fluid flows out, but does not result in a substantial decrease in the pressure within the pressure vessel. Or, only the outlet has the above structure.
Continuous processing of a polymeric material, characterized in that the long body passes smoothly through the supply port, but the pressurized fluid in the pressure container does not substantially leak out from the gap created between the long body and the long body. The present invention provides a rolling and stretching device.

The apparatus of the present invention is mainly composed of a pressure container and a stretching mechanism. The main body of this pressure-resistant container may be made of any material and shape as long as it can withstand the required processing pressure, and there are no particular restrictions, but in terms of pressure resistance, durability, processing efficiency, etc. It is advantageous to use cylindrical containers or prismatic containers made of corrosion-resistant metal. Examples of such metals include stainless steel, chrome steel, nickel steel,
Examples include SCM steel and steel.

In addition, the pressurized fluid filled in this is a liquid,
It can be any gas; examples of liquids include water,
silicone oil, mineral oil, vegetable oil, glycerin,
Examples of the gas include grease, polyethylene glycol, polyethylene, etc., and air, water vapor, nitrogen, argon, helium, carbon dioxide, etc., respectively. It goes without saying that when using it, it is necessary to select a material that does not have an adverse effect on the polymeric material to be treated. It is advantageous to use a liquid as this pressurized fluid in terms of ease of handling.

The pressure vessel main body is provided with a supply port and a discharge port for the polymeric material on opposing surfaces, and the polymeric material can continuously move through these while being subjected to tensile stress. There is.

The shape of the supply port corresponds to the cross-sectional shape of the elongated body of polymeric material to be treated, and its dimensions are such that the elongated body can pass through it smoothly, but the pressurized fluid in the pressure-tight container cannot pass through it. It may be large enough to allow a small amount to flow out without substantially reducing the pressure inside the container,
It may be chosen such that substantially no leakage occurs. This dimension is determined by considering the viscosity of the fluid used and the pressure inside the pressure container, but in reality, it is determined by the gap created between the supply port and the long object passing through it.
This is done by setting within the range of 0.05 to 2.0 mm. On the other hand, the outlet for the polymeric material is selected in the same way as the inlet in that its shape almost matches the cross-sectional shape of the processed long polymeric material, but its dimensions are slightly larger. It is necessary to set it so that the pressurized fluid in the pressure-resistant container can flow out to some extent from the gap created between the outlet and the elongated body passing through it. This is the viscosity of the pressurized fluid,
The size of the gap should be determined taking into consideration the pressure inside the pressure vessel.
This is done by selecting a value within the range of 0.01 to 2.0 mm.
Furthermore, if desired, the structure of the supply port can be the same as that of the above-mentioned outlet.

The pressure container of the present invention is provided with a pressurized fluid outlet at a suitable location near the polymeric material supply port, and a pressurized fluid inlet at a suitable location near the takeout port. Through these, the pressurized fluid continuously flows in the pressure container in the opposite direction to the moving direction of the elongated polymeric material, so that the relative relationship of the pressurized fluid to the elongated polymeric material increases. As the speed increases, heat is quickly exchanged from the pressurized fluid, and the temperature of the stretched material is maintained uniformly, resulting in the effect that physical properties are improved even when the stretching speed is increased. . Further, even if this pressurized fluid flows out from the outlet together with the treated elongate object, the elongate object is isotropically pressurized without a decrease in the pressure within the pressure container.
Furthermore, in the apparatus of the present invention, means for adjusting the temperature of the fluid at the supply port, the outlet, and the vicinity thereof, specifically, means for controlling the flow of the fluid, cooling, etc., can be provided as desired. Further, as an auxiliary means for pressure regulation, a pressure regulating/closing control valve, valve, etc. may be provided in a pressure-resistant container or in a fluid system.

The pressurized fluid can be introduced and discharged independently, but from the standpoint of effective energy use, the discharged fluid should be adjusted to the required pressure via a pressure regulating valve, compressor, etc. as necessary. , it is preferable to circulate it to the introduction hole. Moreover, the pressure fluid flowing out from the outlet together with the elongated polymeric material can be collected by appropriate means as necessary and recycled for reuse.

In the apparatus of the present invention, heating means, cooling means, etc. may be provided as desired in order to stretch the polymeric material under heating or to lower the temperature of the pressurized fluid that has been increased by the heat generated by the stretching. can. As this heating means, any means commonly used in conventional stretching apparatuses can be used, such as an external heating method using steam or an electric heater, an internal heating method, or a high frequency dielectric method. The heating means may be provided outside the pressure vessel, or may be provided at any location in the pressurized fluid circulation system. Alternatively, a special preheating zone can be provided to heat the polymeric material just before it is fed into the pressure vessel. Furthermore, depending on the stretching speed and equipment conditions, it may be effective to reduce the dead space locally by inserting fillers or rollers, for example, in order to increase the flow rate of the heating medium near the polymer material being stretched. It is.

Next, as the stretching mechanism, any one can be selected from among the means commonly used for stretching a long body of ordinary polymeric material, but usually a supply roll and a pull-out roll with different rotation ratios are used. A combination is used. In addition, a belt method, a track pillar method, etc. can also be used.

Examples of polymeric materials that can be treated with the apparatus of the present invention include crystalline plastics such as polyoxymethylene, polyethylene terephthalate, nylon 6, nylon 66, polyethylene, polypropylene, polytetrafluoroethylene, polyparaphenylene terephthalamide, Examples include, but are not limited to, aromatic polyamides and imides such as polyparaphenylenebenzbisthiazole, and amorphous plastics such as polymethyl methacrylate and polyacrylonitrile. In addition, the shapes of these polymer materials are as follows:
Examples include filaments, films, tapes, sheets, long plates, tubes, round bars, square bars, irregular cross-section long bodies, and the like.

Next, embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

FIGS. 1 and 2 are cross-sectional explanatory views showing an example of the apparatus of the present invention, in which a long polymeric material A is passed from a feeding roller 1 to supply rollers 2 and 2' to a pressure-stretching device B. supplied to Note that a plurality of elongated polymeric material bodies can be supplied. This stretching device includes a pressure holding member 3 having a supply port 12 and a take-out port 1.
It consists of a cylindrical container 5 equipped with a pressure retaining member 4 having a diameter of 3 at both ends, a pressurized fluid outlet 14 on the supply port side, and a pressurized fluid inlet port 15 on the outlet side. is filled with pressurized fluid C as a medium. The elongated body A is passed through this pressurized stretching device B.
While passing through the cylindrical container 5, it is pressurized to a required pressure by the pressurized fluid C, and is stretched while being heated by the heaters 11 and 11' arranged outside the cylindrical container 5 via the pressurized fluid C. Thereafter, it is taken out, passed through take-up rollers 6 and 6', and then wound onto a take-up roller 7. The supply port 12 and the take-out port 13 provided in the holding members 3 and 4, respectively, have seals that allow the elongated body A to pass through smoothly but do not cause a pressure drop in the stretching device B. This sealing is achieved by appropriately adjusting the opening so that the fluid can flow out from the gap between the opening and the object passing through, and the pressure loss caused at that time can be maintained.

Next, the pressurized fluid introduced from the pressurized fluid inlet 15 and the pressurized fluid discharged from the pressurized fluid outlet 14 may be prepared independently, but in order to reduce energy consumption as much as possible, both are connected by pipes 18, 19 and a pressurized fluid reservoir 21, and circulated using a compressor 8. Further, the pressurized fluid C can be heated by a heater placed at an appropriate position in the circulation path instead of using the heaters 11, 11' placed outside the cylindrical container 5 as described above. The pressure is adjusted using pressure regulating valves 9 and 10.
It is carried out by.

The pressurized fluid flowing out from the outlet 13 together with the treated elongated body is collected in the collection chamber 16 and circulated through the pipe 20 for use. Further, the collection chamber 17 and the conduit 20' on the supply port side can be provided as necessary.

The apparatus of the present invention may be constructed from a single pressure vessel, or may include a plurality of pressure vessels B, B' as shown in FIG. In the latter case, the processing conditions in each pressure container may be the same or may be different, and the desired stretching can be carried out in several stages. Furthermore, if necessary, a preheater, a cooler, a washer, a maturing device, a liquid recovery section for removing the liquid adhering to the stretched body and recovering the fluid, etc. can be incorporated. Moreover, the apparatus of the present invention may be installed horizontally for stretching, or may be installed vertically for stretching in the vertical direction.

Next, FIG. 3 shows a pressure retaining member 4 having an outlet 13.
FIG. 2 is a perspective view showing an example of a structure consisting of a nozzle connected to a thick-walled cylindrical container 5; The nozzle portion can also be formed into a slit as shown in FIG. 4, depending on the shape of the material to be drawn.

Effects of the Invention The device of the present invention is a practical device for continuously stretching a long polymeric material.According to this, it is possible to stretch the polymeric material while applying isotropic pressure. , Even if the stretching speed increases, the heat generated during stretching can be quickly removed, and heat is quickly transferred to the polymeric material via the pressurized fluid under heating. It has the advantage that physical properties can be improved because the stretching temperature can be made uniform.

EXAMPLES Next, the present invention will be explained in more detail with reference to Examples.

Example A polyacetal tape (Tenatsuku 3010, thickness 0.20
mm, width 5 mm) was continuously pressure stretched at high speed.
The first stage device and the second stage device are respectively
A pressure vessel with a total length of 2m and a cavity of 10mm inside diameter.
A slit with a gap of 0.25 mm, a width of 5 mm, and a length of 200 mm is attached as a pressure holding member. Further, within this pressurized stretching device, the direction in which the polyacetal moves and the direction in which the pressurized fluid moves were set in countercurrent directions.

The first stage equipment uses silicone oil at 150℃ as the pressurized fluid, which is circulated by a high-pressure metering pump at about 0.5 per minute to maintain an internal pressure of about 50Kg/ ^cm2.
Meanwhile, in the second stage equipment, silicone oil at 170℃ is used as the pressurized fluid, and this is circulated by a high-pressure metering pump at about 0.5 per minute to maintain the internal pressure at about 200Kg/ ^cm2 . Meanwhile, the polyacetal tape is fed into the first stage apparatus at a speed of 50 cm/min, taken out at 4 m/min, and stretched 8 times.
Next, this material was supplied to the second stage apparatus at a rate of 4 m/min and taken out at a rate of 8 m/min, and was stretched a total of 16 times.

The stretched body obtained in this way is transparent,
The tensile modulus was 30 GPa and the density was 1.45 g/cm ³ .

In addition, when stretched under the same conditions as above except that the moving direction of the polyacetal and the moving direction of the pressurized fluid were the same, the transparency decreased slightly, the tensile modulus was 27 GPa, and the density was 1.42. g/ ^cm3 . That is, the tensile modulus of the film stretched in the countercurrent direction was about 10% higher than that of the film stretched in the same direction.

Furthermore, the stretching speed of polyacetal was reduced to 1/5,
The temperature of the first stage is 150℃, the temperature of the second stage is 163℃
Stretched at the same stretching ratio and pressure, except for
A comparison was made between cases where the moving direction of polyacetal and the moving direction of the pressurized fluid were countercurrent to each other, and cases where they were the same. In both cases, the obtained drawn body was transparent, had a tensile modulus of 30 GPa, and a density of was 1.45g/ ^cm3 .

From these facts, it was found that the effect of stretching in the countercurrent direction of the present invention appears particularly when the stretching speed is high.

For comparison, when stretching was performed in air under normal pressure without using a pressurized fluid under the same stretching conditions, when the stretching speed was 8 m/min, the obtained product was white and had a tensile modulus of elasticity. is 20GPa, density is 1.22g/
It was warm at ^cm3 .

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional explanatory diagram showing an example of the device of the present invention;
FIG. 2 is a cross-sectional explanatory view showing an example equipped with two pressure-resistant containers, and FIGS. 3 and 4 are perspective views of different examples of pressure-retaining members, and the reference numeral A in the figure is a long piece of polymeric material. body, B and B′ are pressurized stretching devices, C is pressurized fluid,
1 is a material supply section, 2, 2' are supply rollers, 3, 4
is a pressure holding member, 6 and 6' are take-up rollers, 7 is a winder,
8 is a pump, 9 and 10 are valves, 11 and 11' are heaters, 12 and 13 are a polymeric material supply port and an output port, respectively, 14 and 15 are a pressurized fluid discharge port and an inlet port, respectively, 16 and 17 is a pressurized fluid receiver, 1
8, 19 are connection pipes for pressurized fluid circulation; 20;
20' is a recovery pipe for pressurized fluid, and 21 is a pressurized fluid reservoir. 3 and 4 are perspective views showing different examples of the structure of the pressure retaining member, with FIG. 3 showing a nozzle structure and FIG. 4 showing a slit structure.

Claims (1)

[Claims] 1. A continuous container comprising a pressure-resistant container in a substantially sealed state filled with a pressurized fluid and a stretching mechanism for applying tensile stress to a long body of polymeric material that continuously moves through the container. In the pressure stretching device, a pressurized fluid outlet is provided on the supply port side of the polymer material elongate body of the pressure-resistant container, and a pressurized fluid inlet port is provided on the take-out port side, and both the supply port and the take-out port are provided. , and the elongated body passing through them, the dimensions are such that a small amount of pressurized fluid can flow out but do not cause a substantial drop in the pressure inside the pressure vessel, or only the outlet is configured as described above. A polymeric material having such a structure that the elongated body can smoothly pass through the supply port, but the pressurized fluid in the pressure container does not substantially leak out from the gap created between the elongated body and the elongated body. Continuous pressure stretching equipment.