JPS62184834A - Manufacture of thermoplastic resin sheet - Google Patents

Abstract

PURPOSE:To obtain a sheet, the strength, elastic modulus and shock resistance of which are high and which has uniform physical properties in the longitudinal and lateral directions, by a method wherein raw sheet or plate material, n the shape of which the ratio of thickness to width is above a certain value, is unaxially rolled in such a manner that its widthwise elongation is half or more than its lengthwise elongation. CONSTITUTION:A single layer or laminated layers of molten resin, which is left in natural cooling, are rolled under the predetermined temperature conditions. At this time, the ratio of thickness to width of a raw material resin layer or of raw material resin layers is made to be 0.1 or more, preferably 0.2 or more. If said ratio of a raw material resin layer is below 0.1 because the ratio of thickness/width of a product being small, the rolling is done in the state that said ratio is kept to be 0.1 or more by laminating raw material resin layer. A product is obtained by separating into a single layer after rolling. In addition to the rolling condition as mentioned above, said rolling is made so as to satisfy the condition that the widthwise elongation of the resin is made to be 50% or more of its lengthwise elongation. The obtained sheet 7 can have excellent physical properties in both the long and width directions.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing a biaxially oriented thermoplastic resin rolled sheet.

[Prior Art] Biaxially oriented molecules of a thermoplastic resin by rolling, stretching, etc. at or below the melting point improve its mechanical properties, such as strength, elastic modulus, and impact resistance. is well known. Taking advantage of this property, in the case of thin films, it is widely practiced to simultaneously stretch the film in two directions to continuously produce a biaxially stretched film. For thick sheets, when the required power for stretching increases,
Stretching is only used to produce thin sheets because of uneven stretching and uneven physical properties. Batch-type methods such as cross-roll rolling and solid phase extrusion are used as an alternative to stretching. On the other hand, by rolling polypropylene continuously in one direction under specific conditions,
Although an invention for obtaining a sheet with properties similar to the axial orientation is known (Japanese Patent Application Laid-Open No. 56-33924), the properties are not sufficient.

[Problems to be Solved by the Invention] The object of the present invention is to provide a sheet that has high mechanical properties such as strength, elastic modulus, and impact resistance, and has uniform physical properties in the longitudinal and lateral directions. It's about finding a way to get it.

[Means for Solving the Problems] The present inventors have conducted extensive research in view of the above-mentioned objectives, and have found that when rolling thermoplastic resins, conventionally thick sheets or temporary materials (hereinafter referred to as raw material notes) are used as raw materials for rolling thermoplastic resins. Surprisingly, it has been found that when the sheet is continuously rolled in the uniaxial direction using a belt or roll, a sheet oriented in the biaxial direction and having extremely good physical properties can be obtained. In addition, it has been found that if a thin sheet is desired, the raw material sort can be stacked and rolled, and then peeled off. Furthermore, the tree I used in these cases
It has also been found that polyolefin resin or thermoplastic polyester resin is suitable as II.

That is, when manufacturing a sheet by rolling a thermoplastic resin, the present invention changes the shape of the raw material sheet or plate so that the ratio of thickness to width (thickness 7 width) is 0.1 or more in the l-axis direction. This is a method for producing a thermoplastic resin sheet, which is characterized in that rolling is performed to make the elongation in the width direction 50% or more of the elongation in the length direction.

Thermoplastic resins used in the present invention include polyolefin resins such as polyethylene and polypropylene, thermoplastic polyester resins such as polyethylene terephthalate and polybutylene terephthalate, nylon-6, and nylon-6.
6.6 etc. polyamide resin, polystyrene resin, polymethyl methacrylate resin, thermoplastic polyurethane resin,
Examples include ethylene vinyl acetate copolymer, ethylene vinyl alcohol copolymer, and polyacetal resin.

Among these, polyolefins and thermoplastic polyester resins, particularly polypropylene and polyethylene terephthalate, are preferably used.

A sheet or plate (hereinafter referred to as a sheet) as used in the present invention refers to a sheet having a thickness of 0.1 mm or more, preferably 0.2 mm or more.

A specific method of implementing the present invention is to mold a thermoplastic resin sheet in advance by casting, profile extrusion, injection molding, press molding, etc., preheat this sheet as necessary, and then use it as it is or stack several sheets. The resin is passed through a roll mill or a belt mill in one direction, or the molten resin obtained from the extruder is cooled as it is and rolled in a single layer or in layers under a predetermined temperature condition. At this time, the ratio of the thickness and width of the raw material resin layer to be rolled (thickness 7 width) is extremely important and needs to be 0.1 or more, preferably 0.2 or more. If the (thickness 7 width) ratio of the product is small, and this ratio of the raw resin layer is less than 0.1, it is laminated and rolled while keeping this ratio more than 0.1, and then one layer is rolled. Peel each piece to create a product.

Under such conditions and by making the elongation in the width direction 50% or more of the elongation in the length direction, a sheet having excellent physical properties in both the length and width directions can be obtained.

The roll rolling equipment used in the present invention has at least one pair of rolls, and by passing between the rolls,
The sheet is rolled. The rolls may have a crown or may be crossed, but wood-wise they have parallel gaps. Further, the speeds of the rolls forming the pair do not need to be equal, and the shearing force may be applied to the sheet by setting a speed difference. In equipment having one or more pairs of rolls,
Stretching may be applied by creating a speed difference between the pair of rolls, but it must be kept within a range that does not impede the stretching in the width direction.

First, the belt rolling equipment used in the present invention has a structure such as a double steel heald conveyor, and has at least one pair of belts reinforced from the back side of the belt with backup equipment that can withstand strong pressure. It is a device that does There is no need for the belt gap to gradually decrease here. In the above apparatus, rolling is performed by sandwiching both sides of the raw material resin sheet layer between belts and applying pressure by or through the belt surfaces. An example of such a device is shown in FIG. The preheated raw material sheet 6 is rolled by a pair of rolls 1.1°, held between a stainless steel belt 5.5° backed up at 3.3°, and then taken out.

In the present invention, various fillers can be added to the thermoplastic resin. The fillers used include fibrous fillers such as glass fiber and vinylon fiber, mica,
Examples include flaky fillers such as talc, spherical fillers such as glass peas, and amorphous fillers such as calcium carbonate and wood flour.

The amount added is not uniform because it is limited by usage, manufacturing problems, etc., but it is generally in the range of 5% by weight to 70% by weight. Blends with other resins, extenders, colorants, flame retardants, deterioration inhibitors, stabilizers, antistatic agents, lubricants, etc. can also be added to these filler ponds.

The sheet obtained by the present invention can be used as it is for various walls (e.g., etc.), and can also be used for thermoforming, press molding, etc. for various electrical appliances, OA equipment, automobiles, vehicle parts, various containers, etc. Used for helmets, etc.

[Examples] The present invention will be specifically explained below using Examples and Comparative Examples.

Example 1 Six thick plates (thickness 40III111, width 400 mm) of polypropylene (Noblen MH8, manufactured by Mitsubishi Yuka Co., Ltd.) were
After preheating the sheets to 160°C, they were laminated and simultaneously rolled in one direction (roll temperature: 140°C). After cooling, it was peeled off to obtain six sheets with a thickness of 6 mm. These sheets are approximately 2.8 times larger and 2.5 times larger in the rolling direction and width direction, respectively.
It has been rolled 4 times.

The physical properties of the obtained sheet are shown in Table 1. Roll rolling direction,
It can be seen that it has high impact resistance in both width directions and has small anisotropy.

Comparative Example 1 A polypropylene thick plate having a thickness of 12 mm and a width of 200 mm was used to perform roll rolling in the ■ direction at a preheating temperature of 160°C and a roll temperature of 140°C. The elongation in the roll direction was 4.9 times, and the elongation in the width direction was 1.2 times. The physical properties of this sheet are shown in Table 1.

Example 2 Ten thick plates (6 mm thick, 200 mm wide) of polyethylene terephthalate ([η] = 0.85), 120
After preheating to ℃, they are laminated and simultaneously rolled in one direction (
Roll temperature: 120°C). After cooling, it peels off to a thickness of 1
Obtained 100 mm sheets. These sheets have been rolled approximately 27 times and 2.5 times in the roll direction and width direction, respectively.

The physical properties of the obtained sheet are shown in Table 1. It can be seen that it has high impact resistance in both the rolling direction and the width direction, and the anisotropy is small.

Example 3 A test similar to Example 1 was conducted using a belt rolling machine instead of the rolls. The six sheets obtained were rolled 2.9 times in the machine direction of the belt and 2.5 times in the width direction.

The physical properties of this sheet are shown in Table 1.

Example 4 Using a thick plate made of various resins with a thickness of 15 mm and a width of 30 mm+,! directional rolling was performed using a roll rolling machine. The conditions and results are shown in Table 2.

Example 5 Rolling in one direction was performed in the same manner as in Example 1 except that various fillers were mixed. The conditions and results are shown in Table 3.

Margin below [Effects of the Invention] According to the present invention, by rolling in one direction, it is possible to obtain a sheet that is uniform in both the longitudinal and transverse directions and has high physical properties such as strength, elastic modulus, and impact resistance.

[Brief explanation of drawings]

FIG. 1 is a process diagram showing the manufacturing process using the belt rolling apparatus of the present invention. ! , l° is the drive roll, 2,2° is the tension roll,
3.3' is a backup roll, 4.4' is a heater,
5.5° is a stainless steel belt, 6 is a raw material sheet, and 7 is a rolled sheet.

Claims (1)

[Claims] 1) When manufacturing a sheet by rolling a thermoplastic resin, the shape of the raw material sheet or plate is determined by the ratio of thickness to width (
A thermoplastic resin sheet characterized by being uniaxially rolled so that the ratio (thickness/width) is 0.1 or more, and the elongation in the width direction is 50% or more of the elongation in the length direction. manufacturing method. 2) The method for producing a sheet according to claim 1, wherein rolling is performed using one or more pairs of rolls. 3) The method for producing a sheet according to claim 1, wherein rolling is performed using one or more pairs of belts. 4) Laminate raw material sheets or plates with a ratio of thickness to width (thickness/width) of 0.1 or less, so that the ratio of thickness to width (thickness/width) is 0.1 or more. Claims 1, 2 or 3 which are rolled and then peeled off.
Manufacturing method of the sheet described in section. 5) The method for producing a sheet according to claim 1, 2, 3, or 4, wherein the thermoplastic resin is a polyolefin. 6) The method for producing a sheet according to claim 1, 2, 3, or 4, wherein the thermoplastic resin is polyester. 7) Claims 1, 2, 3, 4, 5, or 6 contain a fibrous filler, a flake filler, or an amorphous filler in addition to the thermoplastic resin.
Manufacturing method of the sheet described in section.