JPH04275127A - Crystalline thermoplastic synthetic resin thin plate and preparation thereof - Google Patents

Abstract

PURPOSE:To enhance not only degree of crystallization but also mechanical properties in a direction specific with respect to a surface area direction by adding a glass fiber to a thin plate made of a crystalline thermoplastic synthetic resin so as to orient the same in the definite surface area direction of the thin plate and molding a molten resin into a plate material to gradually cool the molded one. CONSTITUTION:A crystalline thermoplastic synthetic resin 30 mixed with a glass fiber held to a heated molten state is extruded from the die 2 of an extruder to be accumulated in the front part of the gap between the first stage rolls 41a, 41b of a roll molding machine 4 and passed through the roll gap by rotating the rolls 41a, 41b and the resin being contact with the surfaces of the rolls is rapidly cooled to its crystallization temp. to be solidified. By this method, the solidified layers are formed into plate-shaped surfaces to mold a plate material 3. Subsequently, the plate material 3 is passed through the gap between next stage rolls 42a, 42b to advance cooling from the surface layers of the plate material to the interior thereof to complete the solidification or the plate material 3. At this time, by circulating heated oil to the roll hollow parts 411, 412 of the rolls of the respective stages, the cooling of the resin plate is suppressed and the degree of the crystallization of the synthetic resin is enhanced.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin plate of a crystalline thermoplastic synthetic resin having excellent mechanical properties and anisotropy, and a method for manufacturing the thin plate from a melt of the resin using a roll forming machine.

0002

[Prior art] Polyphenylene sulfide resin (PPS)
Resin) has recently attracted attention as a heat-resistant thermoplastic resin, and is being used as a printed substrate for semiconductors and as other engineering plastics. This P
PS resin is crystalline, and by increasing the degree of crystallinity, its mechanical strength can be increased, and the moderate amorphous portion can express flexibility and improve impact resistance. It has excellent properties such as heat resistance and chemical resistance.

[0003] In order to utilize these excellent properties of PPS resin as a structural member, it is necessary to connect plate materials and other molded products of various shapes.

Conventional methods for molding PPS resin plates include injection molding, in which heated molten PPS resin liquid is injected into a mold, solidified and cooled in the mold, and molded into a predetermined shape; A type of extrusion molding method involves extruding a molten resin from an extrusion molding machine through an extrusion die and a forming die to solidify it.

[0005]

[Problems to be Solved by the Invention] In order to utilize the excellent properties of PPS resin as a structural member, a thin plate with a thickness of about 1 to 10 mm is required. Strength and impact resistance properties may be required. Examples of such uses include exterior panels for electrical machinery, structural components for automobiles and vehicles, and lightweight components for aircraft. Conventionally, crystalline materials with excellent directional mechanical properties are suitable for these applications. PPS resin was unknown.

[0006] The above injection molding method can be applied to mold PPS resin sheets, especially thin sheets, and to promote appropriate crystallization during the molding process, but when trying to mold thin sheets as structural materials, For example, it is difficult to produce long and wide products due to mold size restrictions, and poor hot water circulation in the molding gap easily entrains air in the thin plate, creating voids and making it difficult to maintain uniform mechanical strength. What you have is difficult to obtain. Furthermore, it is inevitable that productivity will be low and costs will be high.

[0007] Furthermore, the solidified extrusion molding method described above has been improved by supplying lubricating oil to the inner wall surface of the forming die to prevent the solidified layer of resin from sticking in the forming die (Japanese Patent Laid-Open No. 185428/1983). ), it has become possible to mold highly crystalline resin, but if you try to mold it into a thin plate using this method, the cooling rate in the forming die is high, and PP
With S resin, crystallization is difficult to occur, and in particular, a thin plate with a thickness of 6 mm or less is entirely amorphous. In addition, with this solidification extrusion molding method, the surface smoothness of the product is poor, a separate mirror finishing process is required, and it is difficult to coordinate the extrusion of the molten resin into the extrusion die and the withdrawal of the solidified resin from the forming die. However, it had some drawbacks such as being limited to molding thick materials.

Generally, amorphous resin is formed into a thin sheet using a roll forming method using polishing rolls, but if the resin is heated to a softening temperature that maintains the shape of the resin from the die in a plate shape, the thin sheet can be formed using rolls. Molding is relatively easy. However, for crystalline resins, it is difficult to roll form a resin liquid that is in a molten state at the die exit into a thin plate because it is necessary to crystallize or precipitate crystals during the solidification process.

The present invention has been made in view of the above-mentioned problems, and is a long and wide crystalline PPS resin with a mirror-finished surface, high smoothness, uniform thickness, and excellent productivity. The present invention provides a method for manufacturing a thin plate of crystalline thermoplastic resin, and further aims to supply a thin plate of thermoplastic resin with a high degree of crystallinity and particularly excellent mechanical properties in a specific direction of the surface area. .

0010

[Means for Solving the Problems] The thin plate of crystalline thermoplastic synthetic resin of the present invention includes glass fibers oriented in a certain area of the thin plate, and This is a thin plate of the resin characterized by excellent mechanical properties in the orientation direction.

[0011] Furthermore, the method for manufacturing a crystalline thermoplastic synthetic resin thin plate of the present invention includes extruding a molten resin liquid of a crystalline thermoplastic synthetic resin mixed with glass fibers through a die into the gap between the first rolls of a roll forming machine. The molten resin liquid is formed into a plate material on the surface of the roll, and the plate material is cooled and rolled down by each of the subsequent rolls, and cooling of the plate material is suppressed by heating and insulating each corrugated roll. , is characterized in that the degree of crystallinity of the synthetic resin is increased.

[0012] Furthermore, polyphenylene sulfide resin (PPS resin) or polyether ether ketone resin (PEEK resin) is used as the synthetic resin, and glass fiber, which is a fibrous material, is mixed in advance with the synthetic resin. In particular, carbon fibers or metal fibers (for example, stainless steel filaments) may be blended instead of glass fibers. The thickness of the thin resin plate of the present invention is in the range of 1 to 10 mm.

[0013]

[Function] Inside the board of crystalline thermoplastic synthetic resin, crystals of the resin are mixed with amorphous parts, but the crystal part supports the internal stress within the board caused by external loads of the board, so the board The amorphous part exhibits viscoelasticity and is soft, and absorbs impact loads.

Since the crystalline synthetic resin is mixed with a fibrous material, such as glass fiber, and molded into a plate material, it is effective for reinforcement, but in the present invention, the filamentous fibers of the fibrous material are further added to the plate material. Since it is strongly oriented in the direction of the plane, the mechanical properties are particularly strengthened in the direction of orientation.

[0015]Synthetic resin thin plates having particularly strong mechanical properties in specific directions can be widely used as plate-shaped or band-shaped structural members for applications where large loads are applied in specific directions, and thermoplastic synthetic resins can be used for welding. Since it is easy to join by , it can be used for chemical containers, storage tanks, other chemical structures, and structural members of vehicles, aircraft, and electrical products.

In the method for manufacturing a crystalline synthetic resin thin plate of the present invention, as shown in FIG. It accumulates at the front of the gap between the first stage rolls 41a and 41b, but due to the rotation of the rolls 41a and 41b, the resin liquid that comes into contact with the roll surface when passing through the gap between the rolls is heated to almost the crystallization temperature, solidifies, and solidifies. The layer becomes a plate-like surface and is formed into a plate material 3. Next stage rolls 42a, 4
While passing through 2b, the plate material 3 is cooled from the surface layer toward the inside, and solidification is completed. In the example shown in FIG. 1, each corrugated roll is heated and kept warm by circulating heated oil in the roll hollow parts 411, 412, etc., so that it is not rapidly cooled when passing through the roll gap, and the first stage roll 41a ,41b
The resin plate passing between the rollers 42a and 42b is gradually cooled while radiating heat into the air.

The surface temperature of the first stage roll is controlled to a temperature between the melting temperature Tm of the resin and the glass transition point temperature Tg, and the surface temperature of the next stage and subsequent rolls is slightly lowered, and the temperature of the final stage roll is kept at a temperature around room temperature. The heat is adjusted to

[0018] In PPS resin, Tm=280~2
90°C, Tg = 85-90°C, and crystallization temperature Tc from the molten resin liquid = 190-250°C. The viscosity is approximately 5000±1000 pois so that the resin melt extruded from the die outlet does not flow down from the top surface of the first roll.
A viscosity of e is required, and the viscosity is adjusted by changing the die temperature once the amount of glass fiber is determined. In the case of molding PPS resin, with a blend of 30% glass fiber, 300 to 3
It is important to adjust the temperature to 40°C. First stage roll 41a
, 41b is around 180°C, and the surface temperature T2 of the next stage rolls 42a, 42b is 140-160°C.
It is best to adjust the temperature to 0°C, and the roll surface should be kept at the crystallization temperature Tc.
Therefore, the molten resin solidifies and crystallizes near the roll surface in contact with it, and since the temperature difference (T1 - T2) between both rolls is small, the cooling rate of the thin resin plate is small. , crystallization progresses from the surface to the inside, forming a crystalline resin thin plate.

[0019] A molten resin liquid containing a fibrous substance such as glass fiber mixed in advance with a synthetic resin is extruded and formed into a thin plate using a multi-roll molding machine as described above, so that a fiber-reinforced synthetic resin thin plate can be formed. During cooling and solidification between the rolls, the molten resin liquid is compressed and formed into a thin plate in the gap between the rolls, so the long axis direction of the fibers can be transported by the rolls while being oriented in the same direction as the extrusion direction.
As a result, it becomes possible to manufacture the synthetic resin thin plate in which the surface area of the plate is strengthened in a specific direction.

[0020] If the amount of the fibrous substance blended is small, it will not be useful for reinforcement, but if it is too large, the surface of the product will not be mirror-like and the surface roughness will occur due to exposure of the fibers, resulting in deterioration of the surface properties. A suitable blending amount is 20 to 50%. The shape of the fibers is preferably such that the aspect ratio is about 10 to 30 after extrusion from an extruder. If the aspect ratio is small, orientation is difficult to occur, the anisotropy is small, and it is not particularly effective for strengthening. If the aspect ratio is too large, the fibers will become entangled with each other, making it difficult to uniformly disperse them into the molten resin liquid.

[0021] By increasing the wettability between the resin and the fiber material,
A coupling agent is mixed to improve the adhesion between the fibers and the resin matrix, and if necessary, a pigment for coloring is mixed.

[0022]

EXAMPLES In order to show the steps of the method for manufacturing a crystalline thermoplastic synthetic resin thin plate according to the present invention, the steps will be explained with reference to the schematic diagram of the manufacturing equipment line shown in FIG.

The raw material is pellets mainly composed of synthetic resin, and is charged into the hopper 13 of the extruder 1. The extruder 1 is of a screw type and is equipped with a heating device, and a wide slot-shaped die 2 for forming plates is provided at its tip. The roll forming machine 4 for solidifying and forming resin into a plate shape is of a three-stage type and is made of steel having a hollow part, and the surface is coated with hard chromemet to give a smooth surface. The hollow part of each roll is connected by piping to an oil heating tank, a pump, and a roll shaft hole that communicates with the hollow part of the roll, so that heating oil flows and circulates.
By controlling the oil temperature in the oil heating tank, it is possible to control the roll surface temperature to a desired level. Further, as a heating method, there is also a method using an electric heater in addition to the above.

[0024] Each roll is provided with a roll lifting device and a drive motor for rotating the roll, the first roll 41 is placed close to the die 2, and the front end of the last roll 43 is completely closed. A pinch roll 44 and a cutter 5 are provided for pulling the thin plate which has been solidified and cooled.

[0025] A batch type heat treatment furnace 8 is installed on the front side of the cutting machine.
There is a cooling chamber 81, and a masking laminate molding machine 82 and a cutter are arranged next to each other.

Next, an example will be shown in which PPS resin is used as the crystalline thermoplastic resin.

[0027] The raw material pellets were 100 parts by weight of PPS resin and glass fiber (Nippon Electric Glass Co., Ltd., product name T-71).
7K, shape, diameter 10 μm length 3 mm) and 1 part by weight of an aminosilane coupling agent (manufactured by Union Carbide, product name A1100) as an auxiliary agent were mixed and extruded using a twin-screw extruder to form pellets. It is molded into. The pellets are sequentially dehydrated in a dryer and put into the hopper of extrusion molding machine 1, and heated and melted at about 340°C. It was extruded toward the gap between the first stage rolls 41. The temperature of the resin liquid was determined in consideration of the amount of glass fiber and the positional relationship between the die and the first roll of the roll forming machine so as to have an appropriately high viscosity. The surface temperatures of the first roll 41, the second roll 42, and the last roll 43 were adjusted to 180°C, 150°C, and 40°C, respectively. The distance between the centers of the rolls was adjusted to 800 mm, the circumferential speed of the rolls was adjusted to 500 mm/min, and the gap between the final stage rolls 43 was adjusted to 3 mm. The die exit thickness is determined by the relationship between the viscosity of the molten resin liquid, the peripheral speed of the roll, and the thickness of the finished thin plate.
-15mm.

The PPS resin liquid from the die of the extractor accumulates on the upper surface of the lower roll 41b of the first stage roll 41, while
It is rolled up in the gap between the first stage rolls and formed into a plate shape with solidified front and back surfaces, and then cooled and rolled by the subsequent rolls to form a long and wide PPS resin thin plate with a width of 1250 mm and a thickness of 3 mm. It was cut into lengths and made into sheets. The crystallinity was measured and found to be 20%.

Next, in a batch-type heat treatment furnace 8, the sheet-like thin plates are stacked and held at 200° C. for 4 hours with the upper and lower surfaces sandwiched between stainless steel plates, and then placed in an annealing chamber 81. The mixture was transferred and slowly cooled at a cooling rate of 10°C/h. This heat treatment removes distortion during the roll forming process, increases the flatness of the thin plate, and further transforms the amorphous resin portion into a crystalline phase to increase the degree of crystallinity.

The test results are shown in Table 1. Crystallinity is 45%
The mechanical properties are particularly excellent in the rolling direction. That is, the tensile strength, elongation rate, bending strength, and impact strength all show higher values in the rolling direction than in the direction perpendicular to the rolling direction. The surface quality is also good, with a mirror surface.

[0031]

[Table 1]

[0032] Such PPS resin thin plates are used as wiring boards for electronic devices, and for structural purposes such as chemical plants, automobiles, and aircraft. In this embodiment, a method for forming a PPS resin thin plate with a thickness of 3 mm has been described, but a thin plate with a thickness of 1 to 10 mm can be easily formed using the same process. Moreover, regarding the plate width, it is possible to manufacture the plate with a width of 10 to 1500 mm.

Unlike the present embodiment, a method of controlling the roll surface temperature by disposing an electric heating element in the hollow part of the roll and using electric heating can also be adopted. In addition, although the heat treatment furnace is shown as a batch type, a continuous type heat treatment furnace and a slow cooling furnace are arranged on the same line behind the above multi-roll forming machine to continuously perform thin plate forming and heat treatment. Of course, it is also possible.

[0034]

[Effects of the Invention] By carrying out the crystalline thermoplastic synthetic resin thin plate and the method for producing the same of the present invention, the following effects can be achieved.

Since it is a crystalline resin, it has good dimensional stability,
The coefficient of linear expansion is low and the strength is high, but it is further reinforced with glass fibers, etc., and the fibers are oriented in a specific direction in the plane area of the thin plate, so the tensile strength, elongation rate, and bending strength are particularly high in specific directions. A synthetic resin thin plate having high mechanical properties such as impact strength and excellent as a structural material can be obtained.

In particular, if PPS resin or PEEK resin is used as the thermoplastic resin, it is possible to provide an anisotropic material that has both heat resistance and chemical resistance, and is suitable for synthesis for applications where strength in a specific direction is particularly required. Can be used as a resin thin plate.

Furthermore, the method for producing the crystalline thermoplastic synthetic resin thin plate of the present invention is basically a method using a screw extruder and a multi-stage roll forming machine, and does not require any special equipment, and can produce long and wide sheets. The thin plate can be easily produced, crystallization and fiber orientation can be achieved during the thin plate forming process, and the thin plate has a mirror surface with extremely good surface properties and has unique effects such as high productivity.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the solidification process of a first roll of PPS resin thin plate.

FIG. 2 is a manufacturing process diagram of a PPS resin thin plate.

[Explanation of symbols]

1 Single screw extruder 2 Dice part 3.Synthetic resin thin plate 4 Roll forming machine 41 First roll 42 Next stage roll 43 Final roll 44 Pinch roll 5 Cutting machine 8 Heat treatment furnace 81　Slow cooling furnace 82 Laminating machine

Claims (4)

[Claims] 1. A thin plate of a crystalline thermoplastic synthetic resin, characterized in that the thin plate contains glass fibers oriented in a certain area of the thin plate. 2. A molten resin liquid of a crystalline thermoplastic synthetic resin mixed with glass fiber is extruded from a die into the gap between the first rolls of a roll forming machine, and the molten resin liquid is formed into a plate material on the surface of the roll, By cooling and rolling down the plate material by each roll of the next stage and after, and controlling the heating and heat retention of each corrugated roll, cooling of the plate material is suppressed,
1. A method for manufacturing a crystalline thermoplastic synthetic resin thin plate, comprising forming crystals of the synthetic resin. 3. The crystalline thermoplastic synthetic resin thin plate according to claim 1 or the crystal according to claim 2, wherein carbon fiber or metal fiber is mixed in the crystalline thermoplastic synthetic resin instead of glass fiber. A method for manufacturing thermoplastic synthetic resin thin plates. 4. The method for producing a thin thermoplastic synthetic resin plate according to claim 1 or a thin thermoplastic synthetic resin plate according to claim 2, wherein the crystalline thermoplastic synthetic resin is a polyphenylene sulfide resin or a polyether ether ketone resin.