JPS59198120A - Tubular molding and manufacture thereof - Google Patents

Abstract

PURPOSE:To obtain a novel tubular molding excellent in the mechanical nature and resistances to heat and chemicals by winding an integral composite of a specified length of a reinforcing fiber and polyphenylene sulfide around a mandrel as melted to perform a compression molding. CONSTITUTION:A reinforcing fiber (preferably carbon fiber) 3mm. or more long and polyphenylene sulfide (hereafter called pps) are integrated in such a manner that the content of the reinforcing fiber in the molding reaches 10-70vol% to form a filamentous or sheet-shaped product. Then, this product is wound around a mandrel evenly as heated upto the melting temperature of the pps and then, fed to a pair of tubular mold or tubular rolls to obtain a tubular molding by a compression molding. USE:This is used for driving shafts, pipings requiring resistances to heat and chemicals.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tubular molded article made of polyphenylene sulfide containing reinforcing m-fibers and having excellent mechanical properties, heat resistance and chemical resistance, and an efficient method for producing the same.

Polyphenylene sulfide (hereinafter abbreviated as PPS) has excellent heat resistance and chemical resistance, and has performance suitable for tubular applications such as various types of piping. The current situation is that it has not been put into practical use. In other words, by durable molding, PPS
When trying to obtain a tubular molded product, this method is inherently unsuitable for tubular products, and the tubular product may be partially oriented. However, the reinforcing fibers are cut during molding and the fiber length is significantly reduced, resulting in insufficient mechanical properties, and furthermore, it is impossible to obtain a tubular product with desirable properties due to the influence of the orientation of the reinforcing fibers and weld strength. Furthermore, when molding PPS tubular products by extrusion molding, which is the most common method for molding tubular products, the melt viscosity of PPS itself is too low, making it difficult to mold. However, this problem cannot be solved. Furthermore, in the case of compression molding, P
Since the cooling rate of PS is slow, crystallization progresses significantly and cracks occur due to crystallization shrinkage, making it impossible to obtain a good tubular molded product.

Therefore, the present inventors conducted intensive studies with the aim of efficiently manufacturing tubular molded products made of PPS with excellent balance in mechanical properties, heat resistance, chemical resistance, etc., and found that By integrating the reinforcing long fibers with PPS, then winding the composite in a molten state around a mandrel and compression molding, the fiber length of the reinforcing am was not inhibited and the desired performance was sufficiently maintained. new P
We have discovered that PS tubular molded products can be easily obtained, and have arrived at the present invention.

That is, the present invention relates to a tubular molded product made of PPS containing 10 to 10% of reinforcing fibers, and characterized in that the reinforcing material has a length of substantially 3 cm or more, and a tubular molded product with a length of 3 zm or more. A linear or sheet-like product made by integrating reinforcing fibers and PPS is heated to a temperature at which PPS melts and evenly wound around a mandrel, and then fed to a pair of tubular molds or tubular rolls. PP containing 10 to 70% by volume of reinforcing fibers that substantially maintain a length of 3 or more, characterized by compression molding.
The present invention provides a method for manufacturing an S-tubular molded product.

The PPS tubular molded product of the present invention has a sufficient reinforcing effect by containing 10 to 70% by volume of reinforcing fibers with a length of substantially 3 mm or more, and is also effective against crystallization shrinkage during molding. Since the occurrence of cracks caused by this process is avoided, its mechanical properties are of an extremely high level. Also, P of the present invention
Since PS tubular molded products retain the excellent heat and chemical resistance inherent to PPS, they can be used for applications that require particularly high mechanical properties, as well as for acids, alkalis, and alkalis other than concentrated sulfuric acid and concentrated nitric acid. Extremely useful for piping applications such as salt and various organic chemicals and oils. Furthermore, according to the production method of the present invention, %P
Since the P3-8 tubular molded product can be reinforced with reinforcing fibers continuously distributed in both the longitudinal and circumferential directions, uniform mechanical properties can be obtained, especially when the reinforcing fibers are regularly arranged. With this configuration, it is possible to increase the reinforcing fiber fraction, and it is possible to obtain a tubular molded product having uniform and extremely excellent mechanical properties.

The PPS used in the present invention is composed of 90 mol% IJ, k, preferably 95
Mol% is a polymer containing the above, and the above repeating unit is 9
If it is less than 0 mol %, the crystallinity of the polymer will not be sufficient, leading to a decrease in heat resistance and chemical resistance, which is not preferable. In addition, if less than 10 mol% of the repeating units in PPS are composed of repeating units having the following structural formula, 4- these PPS will have a temperature of 300°C and an apparent shear rate of 200°C.
Melt viscosity measured under 8eC-1 condition is 50-500
00 poise, preferably 100-5000 p
If the melt viscosity is less than 50 poise, sufficient mechanical properties will not be exhibited, and if the melt viscosity is less than 50,000 poise, reinforcing fibers are PPS into the gap
This is not suitable because desired mechanical properties cannot be expected due to insufficient impregnation.

Note that the PPS used in the present invention contains antioxidants, heat stabilizers,
In addition to ordinary additives such as lubricants, crystal nucleating agents, ultraviolet absorbers, colorants, fillers, and mold release agents, short fibers may be further included for the purpose of improving surface smoothness, or the effects of the present invention. It is also possible to blend a small amount of other types of polymers within a range that does not inhibit.

The reinforcing fibers used in the present invention need to have a length of 3 ff or more, and in terms of the reinforcing effect, it is more preferable that they have a length of 5 wm or more. These reinforcing elements can be either continuous or discontinuous, and can be woven, regularly arranged, randomly distributed, or combinations thereof. However, it is important to use long fibers; using short fibers is not preferable because the effect of reinforcing mechanical properties is insufficient and cracking due to crystallization shrinkage during molding cannot be prevented.

The type of reinforcing fiber used in the present invention is not particularly limited as long as it does not melt or decompose at the melt-molding temperature of PPS, and may include inorganic fibers such as glass fiber, metal fiber, asbestos 1-fiber and charcoal fiber, and aromatic fiber. Examples include organic fibers such as group polyamide fibers, and one type or a combination of two or more of these can be used. These reinforcing fibers can also be used after being subjected to various treatments to improve their adhesion to PPs.

Among the reinforcing fibers, carbon fibers are particularly preferably used from the viewpoint of improving mechanical properties and chemical resistance.

The content of reinforcing fibers in the tubular molded product in the present invention is 10
A suitable range is from 20 to 60% by volume, preferably from 20 to 60% by volume. If the reinforcing fiber content is less than 10% by volume, the reinforcing effect is still insufficient even with long fiber reinforcement, in which single fibers exhibit sufficient reinforcing effect, and it is difficult to prevent cracking during molding. If this is exceeded, it becomes difficult to completely fill the reinforcing delicate gaps with PPS, and desirable mechanical properties cannot be expected, which is not preferable.

Reinforcing fibers and P used in manufacturing the tubular molded product of the present invention
The linear object that is integrated with PS is actually several hundred pieces.
A linear product made by impregnating or adhering PPS to a bundle of several hundred thousand reinforcing fibers, preferably 1000 to 30000 reinforcing fibers in the warp direction, and whether or not the reinforcing fibers contained are twisted; Continuous or discontinuous fiber length can be selected as appropriate.

There are no particular restrictions on the method of impregnating or adhering PPS to the reinforcing fiber bundle, such as (1) immersing or passing the reinforcing fiber bundle in molten PPS, (2) using a normal wire coating die. A method of coating a reinforcing fiber bundle with molten PPS, (3) a method of attaching powdered PPS to a reinforcing fiber bundle and heating it to a temperature above the melting point of PPS, and (4) a method of (1), (2) or (3) above. ), followed by a method in which the linear object is passed between at least a pair of rolls in the vertical direction at a temperature higher than the melting point of PPS, etc., but method (4) is particularly effective because the condition of the linear object is Complete filling of the reinforcing fiber gaps with PPS is achieved in this way, which makes it easier to obtain a tubular molded product with even better reinforcement efficiency.

In addition, in the present invention, the string-like product formed by integrating reinforcing fibers and PPS refers to a woven fabric, a knitted fabric, a braided fabric, etc., which is formed by weaving and weaving strands in which reinforcing fibers are bundled. - A sheet-like product in the form of a mesh or a regular or random arrangement of reinforcing fibers of continuous or discontinuous length, which is made by integrating these reinforcing fibers with PPS; There is no particular restriction on the thickness, but from the standpoint of ease of molding into a tubular molded product, thinner materials are preferably used. Sea 1 by integrating reinforcing fiber and PPS
There are no particular restrictions on the method of forming a --shaped material, including a method of superimposing +11 reinforcing fibers and PPS and hot pressing; (2)
Examples include a method in which PPS is extruded and coated on reinforcing fibers using a cross-layer rad die, and (3) a method in which PPS is extruded and laminated on reinforcing fibers, in which the reinforcing fibers are not woven or woven but are arranged regularly or randomly. In the case of the form
A method of arranging the linear objects in the present invention regularly or randomly and heating and integrating them is also possible. Further, as a method of heating and integrating, a method may be adopted in which reinforcing fibers and PPS are supplied between a pair of endless belts and heating, pressurization, and cooling are performed continuously.

In the present invention, there is no particular restriction on the method of winding the linear or sheet-like material formed by integrating reinforcing fibers and PPS around a mandrel as long as the PPS is in a molten state. can be wound evenly by appropriately selecting the angle between the mandrel axis direction and the linear object, and in the method of winding the sheet 1 ~ shaped object,
A method of winding a sorted material with the width matching the length of a tubular material, a method of winding a ribbon-like sheet material at an arbitrary angle with the mandrel axis direction, and a combination of these methods.
It is possible to take this method. At this time, the mandrel temperature and the ambient temperature do not necessarily have to be higher than the melting point of PPS, but higher temperatures are preferable in terms of improving the surface condition of the inner surface of the molded product and reducing voids in the molded product. Further, the shape of the mandrel allows a slight draft angle to be provided, and it is also possible to apply a mold release agent. It is best practice to wind the PPS around the mandrel in a molten state without cooling it, following the process of integrating PPS and reinforcing fibers to obtain a linear or sheet-like product. Parallel to the winding process, it is also possible to press the wire or seal onto the mandrel with a roll 4.

The method of substantially compression molding using a pair of tubular molds or tubular rolls in the present invention includes a method of performing compression molding with a mold at a temperature above the melting point of PPS, and a method of performing the compression molding with a mold or rolls at a temperature below the melting point of PPS. It is possible to select either one. If PPS is not sufficiently impregnated into the reinforcing fibers in the linear or sheet-like material wound around the mandrel, or if the PPS wound around the mandrel has already solidified, It is necessary to perform compression molding with a pair of molds set at a temperature above the melting point of pps, while if the impregnation is sufficient and the PPS is in a molten state, a mold set at a temperature below the melting point of %PPS is used. Shaping and cooling can be performed simultaneously by compression molding, or by passing it between a pair of rolls that have a gap corresponding to the cross section of the tubular molded product and are set at a temperature below the melting point of PPS. It is possible, and the latter method in particular is superior in terms of productivity.

The thus obtained PPS tubular molded article of the present invention is extremely useful not only for various drive shaft applications that require mechanical strength, but also for various piping applications that require particularly heat resistance and chemical resistance.

The effects of the present invention will be further explained below with reference to Examples.

Example 1 A carbon fiber bundle (Toreka 'T300 manufactured by Toshiku Co., Ltd.) made by bundling 3000 carbon fibers with a diameter of 7 II was heated at a temperature of 30
The carbon fibers were passed through PPPS (manufactured by Phillips Petroleum, USA) which was in a molten state at 0°C, and taken from a die with a diameter of 1.5 ff, and then passed between a pair of iron rolls set at 300°C to form carbon fiber bundles. A wire impregnated with PPS was obtained. The obtained linear material was cut into a length of about 4 fl, and then randomly agglomerated, and compression molded using a pair of flat molds set at 30012-°C to give a length of about 0.4 fl.
A sheet material having a thickness of 5 mm was obtained. A rectangular piece with a width of about 200 fins and a length of about 1.2521 m was cut out from this Sea 1~ shaped piece.
220m long, heated to 330℃ in a hot air heating furnace.
Diameter 18 dragon (draft angle Q) so one end is 1.7.8
The mold release agent (S H-7020' manufactured by TOMU Silicone Co., Ltd.) was applied to the surface of the round rod shape, and after winding it around a mandrel heated to 300℃, each piece was shaped into a semi-cylindrical shape. A pair of 20 mm Φ x 220 mm cylindrical molds (
301g / 301g /
It was held at a pressure of cd for 2 minutes.

This was then transferred to a press using cooling water to cool it down, and a tubular molded product with an inner diameter of 18 mm, an outer diameter of 20 mm and a length of 200 mm was obtained.

The surface condition of the inner and outer surfaces of this tubular molded product was good. Furthermore, the carbon fiber content in this molded product was 24% by volume, and when a compression test was performed on a 20fl length tubular piece cut out from this tubular molded product in a direction perpendicular to the longitudinal direction, the breaking load was 105%. kq, and had excellent mechanical strength. The fracture stress calculated from this fracture load by determining the maximum moment generated within the specimen from the relational expression M=WR7π was 24 kq/-.

(Here, M is the moment, W is the load, and R is the radius of the tube.) Comparative Example 1 Carbon fiber chopped strands of PPS used in Example 1 and silk with a fiber length of 6 Trading card 'T300''l manufactured by Co., Ltd.
The mixture was melt-kneaded in an extruder at a weight ratio of 70:30 and then pelletized, which was then subjected to injection molding to obtain a tubular molded product with an inner diameter of 18 mm, an outer diameter of 20 mm, and a length of 100 mm. The gate of the mold used for injection molding was a film gate placed at one end of the tubular product in the longitudinal direction, and the molding was performed with the melting temperature and mold temperature set at 300° C. and 120° C., respectively. The surface condition of the obtained tubular molded product was relatively good, but when a compression test was performed in the same manner as in Example 1, the breaking load was 29 kq, the corresponding breaking stress was 6.6 kQ/-, Mechanical strength was insufficient.

The carbon fiber content in this tubular molded product is 25% by volume.
, the length of the carbon fibers is 02 to 0.5 silk, and the orientation in the longitudinal direction of the molded product is significant.

Comparative Example 2 Pellet I, which was obtained by melting and kneading the PPS and carbon fines used in Comparative Example 1, was supplied to the mold used in Example 1 with a mandrel arranged, and heated to the same temperature as in Example 1. Compression molding was carried out under the following conditions.

When the mold was opened after cooling, cracks had appeared in the longitudinal direction of the molded product, and a good molded product could not be obtained.

Example 2 Glass fiber fabric (MS-2 manufactured by Asahi Fiberglass Co., Ltd.)
50. PPS with a weight of 208g/m') and a thickness of approximately 0.2mm
The sheets are stacked one on top of the other.

A composite sheet with a thickness of about 0.25 mm was obtained by compression molding in a flat mold set at a temperature of 300°C. Width approx. 20011mm from this sheet. A rectangular piece of silk with a length of approximately 250 mm was cut out and molded in the same manner as in Example 1, with an inner diameter of 18 ffI! A tubular molded product with an outer diameter of 20 m and a length of 200 m was obtained. The glass fiber content in this molded article was 56% by volume, and the breaking load and stress measured in the same manner as in Example were 260 kg and 59 kg, respectively.
It had an excellent mechanical strength of kq/-.

Example 3 The carbon fiber bundle used in Example 1 was passed through PPS in a molten state at a temperature of 300°C, and while being taken from a die of 1.0 mm diameter, it was heated 20 times/min in a hot air heating furnace at 300°C. 4) was fed to a mandrel with a diameter of 30 wm rotating at a speed of 30 wm in the longitudinal direction of the mandrel while reciprocating at a cycle of 3 times/min, and a length of about 110 Q m was evenly wound around the mandrel. Next, apply silicone-based lubricating grease (5H manufactured by Lesharu Silicone Co., Ltd.) to the surface of the mandrel wrapped with the linear material in the shape and dimensions shown in Figure 1.
-111) is applied, the compressive load between the rolls is 100 kt), and the temperature is 180℃.
After passing through a pair of rolls with a rotational speed of 5 times/min, compression shaping and cooling, the mandrel was removed and a tubular molded product with an inner diameter of 30mm, an outer diameter of 34mm, and a length of 300n was produced. Obtained. In the obtained molded article, the carbon fibers were arranged at an angle of approximately 45 degrees with respect to the longitudinal direction of the molded article, and the carbon fines content in the molded article was 52% by volume.

Furthermore, the breaking load and stress measured in the same manner as in Example 1 were 49 kg/- and 18 kq/-, respectively.

Example 4 5 trading card'T made of carbon fiber (Toshiku Co., Ltd.) with a fiber length of 12 MM
300) is dispersed in the same direction and has a basis weight of 25.
0g/m'' and a PPS sheet of Q, 4+u thickness were stacked and integrated under pressure at a temperature of 300°C to obtain a composite sheet 1- of approximately 0°5 silk thickness.From this sheet A rectangular piece with a width of about 200 mm and a length of about 125 mm was cut out, heated to 330°C in a hot-air heating furnace, and then wrapped around a piece at a temperature of about 260°C using the mandrel used in Example 1. In the second mold used in Example 1, the temperature was 180℃.
The mixture was supplied to a vessel set at ℃, shaped under pressure, and cooled to obtain a tubular molded product.

The carbon fiber content in this molded article was 29% by volume, and the breaking load and stress measured in the same manner as in Example 1 were 121 kq and 28 N/-, respectively.

[Brief explanation of drawings]

FIG. 1 is a front view of a pair of rolls used in an embodiment of the present invention, and all dimension numbers indicate Wll units. Patent applicant Toshi Co., Ltd. Engraving of the grand drawing (no change in content) 19- Procedural amendment 1, Indication of the case Patent application No. 73466 of 1982 2, Name of the invention Tubular molded product and method for manufacturing the same 5. Person making the amendment 41. Date of amendment order: July 26, 1980 (shipment date) 5. Number of inventions increased by the amendment 06. Contents of the drawing Z amendment subject to the amendment

Claims (1)

[Scope of Claims] 1. A tubular molded article made of polyphenylene sulfide containing 10 to 70% by volume of reinforcing fibers, characterized in that the reinforcing fibers have a length of substantially 3 mm or more. A linear or thread-like product made by integrating reinforcing fibers with a length of 2° or more and polyphenylene sulfide is heated to a temperature at which the polyphenylene sulfide melts, and then wrapped uniformly around a mandrel. Composed of polyphenylene sulfide containing 10 to 70% by volume of reinforcing fibers, characterized in that it is supplied to a pair of tubular molds or tubular rolls for compression molding, and the reinforcing fibers are substantially 3% by volume.
A method for manufacturing a tubular molded product having a length of zyx or more.