JPS6147707B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a reinforced thermoplastic resin laminate having excellent strength, which is obtained by laminating and reinforcing a thermoplastic resin molded body with a fiber-reinforced thermosetting resin layer. A thermoplastic resin molded article reinforced by laminating fiber-reinforced thermosetting resins has the excellent physical properties of thermoplastic resins, such as corrosion resistance and abrasion resistance, as well as the excellent physical properties of fiber-reinforced thermosetting resins. For example, it has the advantage of having heat resistance, weather resistance, creep resistance, etc., as well as being lightweight and economical. Therefore, it is widely used in chemical industry materials, water piping materials, reactors, etc. However, although the mechanical strength of the laminate can be expected to be the sum of the respective mechanical strengths of the thermoplastic resin molded body and the fiber-reinforced thermosetting resin layer, in reality, the mechanical strength of the thermoplastic resin molded body and the fiber reinforced thermosetting resin layer are The mechanical strength is not even comparable to that of a resin molded body alone. In order to improve mechanical strength, a polyurethane primer layer is used between the thermoplastic resin molding and the fiber-reinforced thermosetting resin layer, but even if some improvement is possible, it is not always sufficient. It's hard to say. An object of the present invention is to solve the problems of the prior art described above and to provide a reinforced thermoplastic resin laminate having excellent mechanical strength. To summarize the present invention, the reinforced thermoplastic resin laminate of the present invention is a reinforced thermoplastic resin laminate in which a thermoplastic resin molded body is reinforced with a fiber-reinforced thermosetting resin layer. It has adhesive properties between the thermosetting resin layer and the thermosetting resin layer. It is characterized by providing a rubber elastic layer containing a thickness maintaining material. The present inventors have conducted various studies to achieve the above object, and as a result, have discovered the following facts and arrived at the present invention. In other words, not only is the mechanical strength of the reinforced thermoplastic resin laminate not the sum of the mechanical strengths of the thermoplastic resin molded body and the fiber-reinforced thermosetting resin layer, but also the mechanical strength of the thermoplastic resin molded body alone is The reason why it is significantly inferior to the strength is that the thermosetting resin layer is directly formed and laminated on the thermoplastic resin molded body.
For example, when a thin layer of unsaturated polyester resin was directly applied to one side of a polyvinyl chloride resin test piece, cured, and laminated, the bending strength or impact strength was significantly lower than that of a polyvinyl chloride resin test piece alone. In this case, there is almost no elongation on the side where the unsaturated polyester resin is laminated, and if the test piece is bent with this side facing outward, the unsaturated polyester resin layer will be cut and the entire test piece will break.
In other words, instantaneous rupture of the rigid unsaturated polyester resin layer causes an instantaneous notch effect (a phenomenon in which the strength decreases due to the concentrated effect when stress is applied due to the presence of notches) in the polyvinyl chloride resin layer. This causes the entire test piece to break, and this is the reason why the mechanical strength of the reinforced thermoplastic resin laminate is significantly weakened even when a fiber-reinforced unsaturated polyester resin layer is directly laminated onto the polyvinyl chloride resin molded body. Become. And this phenomenon is
This phenomenon was also observed when an unsaturated polyester resin or other thermosetting resin was laminated onto a thermoplastic resin molded product other than a polyvinyl chloride resin molded product. Based on the above facts, the present inventors also tried providing a primer layer of polyurethane or the like as an intermediate layer as described above, but satisfactory mechanical strength could not be obtained (see Comparative Example below). Therefore, the present inventors conducted further studies and focused on using a specific material as the intermediate layer, and first, bonded a rubber elastic layer containing a thickness retaining material as a specific material to a thermoplastic resin test piece. Then, by applying and laminating only a heat-strengthening resin thereon, the bending strength or impact strength of the reinforced thermoplastic resin laminate can be made equal to or higher than the strength of the thermoplastic resin test piece. Admitted. In other words, when the laminate is bent with the heat-strengthened resin layer on the outside, a cut surface will eventually form in a part of the heat-strengthened resin layer, but the cut will not propagate at all to the rubber elastic layer containing the thickness retaining material. No bending occurred, and the entire laminate could be bent without any bending. The present inventors further developed the above facts and completed the present invention, in which a rubber elastic body containing a thickness retaining material is placed at the interface, a thermoplastic resin molded body is placed on one side, and fibers are placed on the other side. When reinforced thermosetting resin was bonded,
It was found that the mechanical strength of the obtained reinforced thermoplastic resin laminate was significantly improved, and was found to be approximately the sum of both mechanical strengths. The thermoplastic resin in the present invention includes polyolefins such as polypropylene, high, medium or low density polyethylene, ultra-high molecular weight polyethylene and polypentene, nylon 6, nylon 11, nylon
12, homo or copolyamides such as nylon 6,6 and nylon 6,10, saturated polyesters such as polyethylene terephthalate and polybutylene terephthalate, chlorine-based resins such as polyvinyl chloride and chlorinated polyvinyl chloride, polycarbonate, polymethyl methacrylate, and Examples include polyphenylene oxide. Further, examples of molded bodies of these resins include sheets, containers, pipes, joints, flanges, etc., but the shape is not particularly limited as long as it meets the purpose of the present invention. Examples of the thickness retaining material in the present invention include glass, carbon, polyacrylonitrile, acetalized polyvinyl alcohol (vinylon), fibers such as nylon and polyester, woven or non-woven fabrics such as hemp, cotton, silk and cellulose, or Japanese paper. Examples include porous bodies, which are impregnated with the rubber adhesive constituting the rubber elastic layer in the present invention to form the skeleton thereof. Further, as the rubber adhesive for the rubber elastic body layer in the present invention, nitrile rubber adhesive, polychloroprene rubber adhesive, butyl rubber adhesive, SBR rubber adhesive, isoprene rubber adhesive, polysulfide rubber adhesive, Examples include silicone rubber adhesives, urethane rubber adhesives, natural rubber adhesives, rubber-based acrylic acid, and higher grade esters. In order to further exhibit the effect, it is desirable to bond the thermoplastic resin molded body and the fiber-reinforced thermosetting resin layer to both layers and to cure the thermosetting resin layer. Furthermore, as the thermosetting resin of the fiber-reinforced thermosetting resin layer forming material in the present invention, for example, unsaturated polyester resin, phenolic resin, epoxy resin, urea resin, melamine resin, diallyl phthalate resin, alkyd resin, silicone Examples include resins and polyimide resins, which can be used as fiber-reinforced thermosetting resins by reinforcing them with various types of fibers in a conventional manner. The rubber elastic body containing a thickness maintaining material (hereinafter referred to as a rubber adhesive), which plays an effective role in the present invention, has the following effects. (1) As mentioned above, by using this as an intermediate layer, it is possible to prevent the fiber-reinforced thermosetting resin layer from directly adhering to the surface of the thermoplastic resin molding, and to improve the mechanical strength of the thermoplastic resin molding. It can prevent a decrease in strength. (2) The rubber adhesive can achieve the effect of (1) by bonding the thermoplastic resin molded body and the fiber-reinforced thermosetting resin layer with sufficient strength. properties such as heat resistance and creep resistance can be imparted to the resin layer. (3) When applying a rubber adhesive to the surface of the thermoplastic resin molding and then bonding the fiber-reinforced thermosetting resin layer while it is still unsolidified, apply the layer while applying pressure to the adhesive. Otherwise, sufficient adhesive strength will not be obtained. However, a phenomenon occurs in which the rubber adhesive becomes extremely thin due to pressurization, and cannot sufficiently exhibit its cushioning effect. However, since the thickness maintaining material of the present invention is sufficiently impregnated with a viscous rubber adhesive, its interfacial tension allows it to withstand strong pressure applied to the fiber-reinforced thermosetting resin layer (FRP layer). endure,
The thickness of the adhesive layer can also be controlled to a desired constant thickness. (4) By using a material with high Young's modulus and strength as the thickness retaining material, it can serve to improve the mechanical strength of the rubber elastic layer. As described above, the reinforced thermoplastic resin laminate of the present invention has a mechanical strength that is equal to or higher than the sum of the mechanical strengths of the thermoplastic resin molded body and the fiber-reinforced thermosetting resin layer, and particularly has a high mechanical strength. Even when subjected to stress-induced strain, stress is not concentrated locally, so mechanical strength is significantly improved, and strain at the joint surface due to large expansion and contraction of the thermoplastic resin molded product can also be significantly reduced. .
Furthermore, by selecting the rubber adhesive having good heat resistance, the heat resistance of the entire laminate can be improved. Next, the present invention and its effects will be specifically explained using Examples and Comparative Examples, but the present invention is not limited by these in any way. Incidentally, the Charpy impact strength and hydraulic fracture strength in the following Examples and the like were measured by the following test method. (1) Shalpey impact test method A test piece with specified dimensions and shape (cuboid shape of 120 mm in length, 10 mm in width, and 10 mm in thickness) was prepared from the obtained molded product, and this was tested according to the Japanese Industrial Standards (JIS K 7111), is mounted and fixed horizontally on a support stand with a distance between fulcrums of 60 mm, and the center between the fulcrums is struck from the thermoplastic resin molded body side of the test piece with a hammer. The energy required for the test piece to break is measured and divided by the original cross-sectional area to determine the impact value. (2) Hydrostatic rupture test method The drawing is a schematic vertical cross-sectional view of the hydraulic rupture test device used in this example, where 1 is a fiber-reinforced thermosetting resin layer, and 2 is a rubber elastic layer containing a thickness retaining material. ,
3 is a thermoplastic resin molded body, 4 is a jig for hydraulic pressure rupture test, 5 is a jig for preventing water leakage, 6 is water, and 7 is water pressure. A jig is attached to the obtained tubular molded product as shown in the drawing, and at this time, the interior of the tubular molded product is filled with water (20° C.). In addition, in the test under load, a load of 50 kg is applied to the center of the tubular molded product for a nominal diameter of 50 mm, 75 kg for a nominal diameter of 75 mm, and 100 kg for a nominal diameter of 100 mm. , increase the water pressure at a rate of 10 kg/cm ² per minute, and measure the water pressure when the pipe breaks. Example 1 A polyvinyl chloride pipe (manufactured by Asahi Yokuzai Kogyo Co., Ltd.) with a nominal diameter of 50 mm, wall thickness of 4.5 mm, and length of 2 m was impregnated with acrylic ester rubber adhesive (CV-350, manufactured by Konishi Co., Ltd.) using Japanese paper. was wound in one layer (thickness: 0.5 mm), and on the outside thereof, four layers (thickness: 2 mm) of glass cloth impregnated with unsaturated polyester resin (Polykyute P-6845N manufactured by Kyushu Toyo Kogyo Co., Ltd.) were laminated. This was left at 20° C. for 48 hours to completely cure the unsaturated polyester resin, and the desired reinforced polyvinyl chloride pipe was obtained. The results of measuring the Charpy impact strength and hydraulic burst strength of the obtained reinforced polyvinyl chloride pipe are shown in Table 1 below. Comparative Example 1 A polyvinyl chloride pipe (manufactured by Asahi Yokuzai Kogyo Co., Ltd.) with a nominal diameter of 50 mm, wall thickness of 4.5 mm, and length of 2 m was coated with a polyurethane resin sealer (manufactured by Kyushu Toyo Kogyo Co., Ltd., Pioneer Sealer) and laminated (thickness 0.5 mm) and cured at room temperature for 2 hours. Next, four layers (thickness: 2 mm) of glass cloth impregnated with the same unsaturated polyester resin as in Example 1 were laminated on the outside thereof. This was left at 20° C. for 48 hours to completely cure the unsaturated polyester resin to obtain a reinforced polyvinyl chloride pipe. The results of measuring the Charpy impact strength and hydraulic burst strength of the obtained reinforced polyvinyl chloride pipe are shown in Table 1 below. Examples 2 to 6 The nominal diameter of the polyvinyl chloride pipe used and the number of layers of glass cloth impregnated with unsaturated polyester resin were changed as shown in Table 1 below.
A reinforced polyvinyl chloride pipe was obtained in the same manner as in Example 1. The obtained reinforced polyvinyl chloride pipe was subjected to the same test as in Example 1, and the results are shown in Table 1 below. Example 7 Acrylic ester rubber adhesive (manufactured by Konishi Co., Ltd.)
A reinforced polyvinyl chloride pipe was obtained in the same manner as in Example 1, except that the thickness of the Japanese paper impregnated with CV-350 was 0.2 mm. The obtained reinforced polyvinyl chloride pipe was subjected to the same test as in Example 1, and the results are shown in Table 1 below. Comparative Examples 2 to 6 The nominal diameter of the polyvinyl chloride pipe used and the number of layers of glass cloth impregnated with unsaturated polyester resin were changed as shown in Table 1 below.
A reinforced polyvinyl chloride pipe was obtained in the same manner as in Comparative Example 1. Regarding this, the same test as in Comparative Example 1 was conducted and the results are shown in Table 1 below. Comparative Examples 7 to 9 Table 1 below shows the results of measuring the Charpy impact strength and hydraulic burst strength of individual polyvinyl chloride pipes having the nominal diameters shown in Table 1 below.

[Table] As is clear from the table, the reinforced polyvinyl chloride pipes of the examples according to the present invention are significantly superior to those of the conventional comparative examples in both terms of shear peace impact strength and hydraulic burst strength. As explained above, according to the present invention, it is possible to solve the drawbacks of the prior art and provide a reinforced thermoplastic resin laminate having excellent mechanical strength.
Therefore, the reinforced thermoplastic resin laminate of the present invention can be used in a wide range of technical fields such as chemical industry, piping materials for various liquids, and large containers such as reactors.

[Brief explanation of the drawing]

The drawing is a schematic vertical cross-sectional view of a hydraulic rupture test device used in an example of the present invention. 1...Fiber-reinforced thermosetting resin layer, 2...Rubber elastic layer containing thickness retaining material, 3...Thermoplastic resin molded body, 4...Jig for hydrostatic fracture test, 5...For water leak prevention Jig, 6...water, 7...water pressure.

Claims (1)

[Claims] 1 In a reinforced thermoplastic resin laminate in which a thermoplastic resin molded body is reinforced with a fiber-reinforced thermosetting resin layer,
1. A reinforced thermoplastic resin laminate, characterized in that a rubber elastic layer containing a thickness maintaining material is provided between the thermoplastic resin molded body and the fiber-reinforced thermosetting resin layer, and has adhesive properties on both sides.