TW202225323A - Thermosetting resin composition - Google Patents

Abstract

The present invention provides a thermosetting resin composition having improved heat shock resistance, and being capable of providing an excellent integrated article of metal and resin through insert molding employing metal insert parts. The thermosetting resin composition is obtainable by adding an elastomer and glass fiber to a thermosetting resin in such an amount that the content ratio of the elastomer to the thermosetting resin in the thermosetting resin composition is larger than 1.0 on the mass basis.

Description

Thermosetting resin composition

The present invention relates to a thermosetting resin composition, in particular, to a thermosetting resin composition which can exhibit excellent durability against repeated thermal shocks.

Background technique Up to now, various resin materials have been widely used for the manufacture of automobile parts, mechanical parts, electrical/electronic equipment parts, etc. due to their characteristics such as light weight, easy molding, and electrical insulation. Among the materials, thermosetting resin compositions are widely used in various fields because they are considered to be excellent in balance in terms of heat resistance, mechanical strength, dimensional accuracy, and cost. In addition, when using such a resin composition to manufacture parts of electrical equipment for automobiles, etc., metal members such as electrodes are often used as inserts, and metal-resin composite integrated products are manufactured by insert molding. In this case, It will be repeatedly subjected to thermal shock (ie high temperature action and low temperature action) with the temperature change of the use environment, so the molded product is required to have the characteristic of not cracking due to the difference in linear expansion between resin and metal, that is, the so-called thermal shock resistance. (Heat and cold shock resistance). As a means of improving such thermal shock resistance, measures such as adding reinforcing materials such as glass fibers to reduce linear expansion and adding elastomers such as elastomers to impart toughness have been considered, and various proposals have been proposed.

For example, Japanese Patent Laid-Open No. 2009-73975 proposes an unsaturated polyester resin composition, which is characterized in that: it contains a thermosetting unsaturated polyester resin, a crosslinking agent, glass fibers and a thermal conductivity of 20-250W In addition to the inorganic filler of /m·K, it further contains styrene-vinyl acetate block copolymer as a low shrinkage agent; thereby, it not only ensures excellent thermal conductivity, but also exhibits the characteristics of minimal shrinkage during curing. However, it is difficult for a molded body obtained by using such an unsaturated polyester resin composition to exhibit sufficient strength, and it is difficult to maintain its shape due to insufficient durability against repeated stress caused by repeated heating and cooling thermal cycles. .

In addition, Japanese Patent Laid-Open No. 2010-235724 proposes a phenolic resin molding material, which contains a novolac-type phenolic resin and a resol-type phenolic resin, which are thermosetting resins, glass fibers, an elastomer and a polyol, and is The following proportions are blended: the total amount of these novolak-type phenolic resins and resol-type phenolic resins is 25-40% by weight, the glass fiber is 45-65% by weight, and the elastomer is 1-6% by weight , and the polyol is 0.5 to 3% by weight; although it has been stated that a molded product such as a resin pulley excellent in mechanical strength and hot and cold shock properties can be formed by this, the molded product obtained from this phenol resin molding material is not only in terms of strength and toughness. In addition to the above-mentioned inherent problems, there is also a lack of thermal shock resistance, and there is still the inherent problem that the molded product will crack when subjected to multiple thermal cycles.

As mentioned above, with regard to the thermosetting resin compositions that have been proposed so far, the degree of improvement in thermal shock properties, in other words, thermal shock properties, has not been sufficiently improved. For a metal-resin composite integrated product manufactured by a molding method such as part molding, if there is an acute-angled portion of the metal insert (that is, an angle that is not chamfered and the angle is about 90° or less) The part) coated with resin still inherently has the problem that cracks easily occur there due to repeated thermal cycles. prior art literature Patent Literature

[Patent Document 1] Japanese Patent Laid-Open No. 2009-73975 [Patent Document 2] Japanese Patent Application Laid-Open No. 2010-235724

Summary of Invention The problem to be solved by the invention Herein, the present invention was made on the background of the above-mentioned reasons, and the problem to be solved is to provide a thermosetting resin composition with improved thermal shock resistance, and another problem is to provide a thermosetting resin composition , which can obtain metal-resin composite integrated products with excellent properties by insert molding operations using metal inserts. Furthermore, the present invention also considers an object of providing a metal-resin composite integrated product having excellent properties obtained by using such a thermosetting resin composition, and an efficient manufacturing method thereof. means of solving problems

However, in order to solve the above-mentioned problems, the present invention includes the following various aspects, and all of the aspects can be suitably implemented. In addition, the various aspects described below can be adopted in any combination. In addition, it should be understood that the aspect and technical characteristics of the present invention are not limited by the following description, but can be recognized based on the overall description of the specification and the inventive idea disclosed in the drawings.

(1) A thermosetting resin composition characterized in that it is obtained by blending a thermosetting resin, an elastomer and a glass fiber, and is structured such that the content ratio of the elastomer/thermosetting resin is greater than 1.0 on a mass basis . (2) The thermosetting resin composition according to the aforementioned aspect (1), wherein the content ratio of the glass fiber/the aforementioned thermosetting resin is 1.0 or more and 5.0 or less on a mass basis. (3) The thermosetting resin composition according to the aforementioned aspect (1) or the aforementioned aspect (2), wherein glass fibers are blended in a ratio of 150 to 450 parts by mass relative to 100 parts by mass of the aforementioned thermosetting resin and 120 to 250 parts by mass of elastomers. (4) The thermosetting resin composition according to any one of the aforementioned aspects (1) to (3), wherein the aforementioned thermosetting resin is selected from unsaturated polyester resins and diallyl phthalate resins among. (5) The thermosetting resin composition according to any one of the aforementioned aspects (1) to (4), wherein the aforementioned elastomer is acrylonitrile butadiene rubber. (6) The thermosetting resin composition according to any one of the aforementioned aspects (1) to (5), which further incorporates carbon fibers. (7) The thermosetting resin composition according to the aforementioned aspect (6), wherein the content ratio of the carbon fiber/the thermosetting resin is 1.0 or more and 3.0 or less on a mass basis. (8) The thermosetting resin composition according to the aforementioned aspect (6) or the aforementioned aspect (7), wherein the carbon fibers are blended in a ratio of 110 to 270 parts by mass relative to 100 parts by mass of the thermosetting resin combine. (9) The thermosetting resin composition according to any one of the aforementioned aspects (6) to (8), wherein the content ratio of the carbon fibers/glass fibers is 0.2 or more and 1.0 or less on a mass basis. (10) The thermosetting resin composition according to any one of the aforementioned aspects (6) to (9), wherein the carbon fibers are pitch-based carbon fibers. (11) The thermosetting resin composition according to any one of the aforementioned aspects (1) to (10), which further incorporates an inorganic filler. (12) The thermosetting resin composition according to the aforementioned aspect (11), wherein the inorganic filler is alumina. (13) The thermosetting resin composition according to any one of the aforementioned aspects (1) to (12), which is used for manufacturing a metal-resin composite integrated product. (14) A metal-resin composite integrated product, which is insert-molded using the thermosetting resin composition according to any one of the aforementioned aspects (1) to (13) in the presence of a metal insert And the maker. (15) A method for manufacturing a metal-resin composite integrated product, characterized in that it comprises: The first step is to perform insert molding using the thermosetting resin composition according to any one of the aforementioned aspects (1) to (13) in the presence of a metal insert, thereby inserting the metal insert. A coating layer composed of the thermosetting resin composition is formed on the surface of the member with a predetermined thickness; and The second step is to harden the coating layer formed of the thermosetting resin composition. (16) The method for manufacturing a metal-resin composite integrated product according to the aforementioned aspect (15), wherein the second step is performed simultaneously with the first step or after the first step. (17) The method for manufacturing a metal-resin composite integrated product according to the aforementioned aspect (15) or the aforementioned aspect (16), wherein the metal insert has an angle of 90° or less than 90°, and on the other hand , so that the corner portion is covered by the coating layer made of the thermoplastic resin. Invention effect

The thermosetting resin composition according to the present invention is beneficial to provide a metal-resin composite integrated product, which can effectively inhibit or even prevent the occurrence of cracks even if the thermal cycle test between -40°C and 200°C is repeatedly performed for many times. .

In addition, the thermosetting resin composition of the present invention further contains carbon fibers, so that the resulting molded product also has excellent sliding properties and good heat dissipation, so it can also exhibit the following characteristics: It can effectively alleviate the heat generation caused by friction. In other words, even the heat generation of the molded product itself can be effectively alleviated.

Form for carrying out the invention In short, the thermosetting resin composition according to the present invention is extremely characterized in that it contains a thermosetting resin, an elastomer and a glass fiber, and is structured such that the elastomer content (X) and the thermosetting resin The ratio (X/Y) of the content (Y) is greater than 1.0 (X/Y>1.0) on a mass basis; thereby, the fluidity and low pressure formability can be improved to ensure good injection formability, and at the same time, the problem of the present invention can be advantageously solved. subject.

As for the thermosetting resin to be used, various thermosetting resins that are not hardened and conventionally known can be appropriately selected. Specific examples include unsaturated polyester resin, diallyl phthalate resin, phenol resin, urea resin, melamine resin, epoxy resin, and silicone resin. These thermosetting resins may be used alone or one of them may be used. Use two or more of them in combination.

In the present invention, among the above-mentioned thermosetting resins, unsaturated polyester resins and diallyl phthalate resins are particularly suitable for use, whereby the object of the present invention can be more favorably achieved. In addition, unsaturated polyester resins are polyesters with unsaturated double bonds in the main chain. Specifically, they are obtained by esterification of polyols with unsaturated polycarboxylic acid components (and saturated polycarboxylic acid components). The polyester is the main body and is known so far, and can be appropriately selected from various commercial products. Such an unsaturated polyester resin may be completely substituted even if it is partially substituted with a vinyl ester resin. In addition, even if the diallyl phthalate resin uses one or more oligomers of diallyl terephthalate, diallyl isophthalate, and diallyl terephthalate, or even pre- There is no harm in making these oligomers or even prepolymers contain the above-mentioned diallyl phthalate monomer.

In addition, elastomers that can be blended into such thermosetting resins include acrylonitrile butadiene rubber (NBR), polybutadiene, butyl rubber, modified NBR, chloroprene rubber, polyvinyl butyral, In addition to rubber-based elastomers such as styrene-butadiene rubber, ethylene-propylene rubber, fluorine-based rubber, and polysiloxane rubber, there are styrene-based, olefin-based, polyester-based, polyurethane-based, and Thermoplastic elastomers such as amide-based, fluorine-based, and rigid polyvinyl chloride-based elastomers, and thermosetting/reactive elastomers such as butadiene/isoprene-based and urethane-based elastomers, etc., can be used alone or in combination . Among them, in the present invention, rubber-based elastomers, especially NBR, are suitable for use, which can contribute to the relaxation of internal stress, contribute to strengthening and toughening, and contribute to the achievement of the object of the present invention.

Furthermore, in the present invention, in order to further strengthen and toughen the thermosetting resin composition and to exhibit a high degree of thermal shock resistance through the synergistic effect with glass fibers described later, a large amount of the aforementioned elastomer is used. That is, when the content of the elastomer in the thermosetting resin composition is X and the content of the thermosetting resin is Y, the ratio of X/Y is configured to be greater than 1.0 on a mass basis, that is, X/Y>1.0, whereby, Even if the thermal cycle test of cooling at -40°C and heating at 200°C is repeated many times, cracks can still be effectively suppressed or even prevented. In addition, the upper limit of the X/Y ratio is generally about 3.0. More specifically, the elastic system is used in a ratio greater than 100 parts by mass relative to 100 parts by mass of the thermosetting resin, and here, it is preferably 120-250 parts by mass, more preferably 130-230 parts by mass use below. In addition, if the amount of the elastomer used is too small, the thermal shock resistance will be lowered and the object of the present invention cannot be sufficiently achieved. In addition, if the amount of the elastomer used is too large, it is easy to cause the problem that the thermal expansion causes the cracks to become larger.

In addition, the glass fibers that can be blended into the thermosetting resin together with the elastomer are used to exhibit low linear expansion characteristics in addition to the reinforcing effect, and the types thereof are not particularly limited. For example, glass fibers can be appropriately selected and used. Glass chopped strand, milled glass (fiber), roving glass, etc. are conventional ones. In addition to the circular cross-section, this kind of glass fiber also has cross-sectional shapes such as oblong cross-section and elliptical cross-section. In terms of fiber length, it is generally less than 10mm, and preferably about 0.1~5mm. Furthermore, when the content of such glass fibers is Z, and the ratio Z/Y to the content of the thermosetting resin (Y) is used in a ratio of 1.0 or more and 5.0 or less on a mass basis, it can be used. Effective low linear expansion characteristics. Specifically, the glass fiber can be favorably used in a ratio of 100 to 500 parts by mass (preferably in a ratio of 130 to 450 parts by mass, more preferably in a ratio of 150 to 400 parts by mass) relative to 100 parts by mass of the thermosetting resin. Here, if the amount of glass fiber used is too small, there will be problems such as difficulty in exhibiting effective low linear expansion properties, and if the amount used is too large, the elastic modulus will increase, and problems such as cracking will occur against shock.

Furthermore, as described above, the thermosetting resin composition according to the present invention, which is formed by blending thermosetting resin, elastomer and glass fiber, preferably further contains carbon fibers, which can effectively improve the performance of the thermosetting resin composition. The thermal conductivity of the formed body can be advantageously imparted with electrical conductivity in addition to the improvement of heat dissipation performance.

Here, as such carbon fibers, conventional ones such as PAN-based carbon fibers, pitch-based carbon fibers, and vapor-grown carbon fibers can be appropriately selected and used, and among them, pitch-based carbon fibers are particularly advantageous for use. The pitch-based carbon fibers are conventionally produced from condensed polycyclic hydrocarbon compounds such as naphthalene and phenanthrene, and condensed heterocyclic compounds such as petroleum-based pitch and coal-based pitch as raw materials, among which mesophase pitch is especially used. It can be used suitably as a raw material. In addition, those with an average fiber length of about 30 µm to 3 mm are suitable for use. Further, in terms of the amount of carbon fiber used, when the carbon fiber content in the thermosetting resin composition is W, the ratio (W/Y) to the thermosetting resin content Y (W/Y) is 1.0 on a mass basis. A ratio of more than 3.0 and less than 3.0 can be suitably employed. In addition, carbon fibers are preferably blended in a ratio of 110 to 270 parts by mass, preferably 120 to 250 parts by mass, relative to 100 parts by mass of the thermosetting resin, and the ratio of carbon fiber (W)/glass fiber (Z) is preferable. The content ratio W/Z is preferably 0.2 or more and 1.0 or less, more preferably 0.4 or more and 0.9 or less, on a mass basis. This is because if the content of such carbon fibers is too small, the effect of its addition will not be fully exerted. In addition, if the content of carbon fibers relative to the thermosetting resin (Y) and glass fiber (Z) is too large, the strength will decrease and cause cracking. and other problems.

In addition, the thermosetting resin composition of the present invention can be optionally blended with silica, mica, calcium carbonate, gypsum, barium sulfate, clay, talc, etc. as inorganic fillers. Besides, it can also be advantageously blended with thermal conductivity Sexual filler. In addition, the thermally conductive fillers include metal nitrides such as boron nitride, aluminum nitride, silicon nitride, etc.; such as magnesium oxide, aluminum oxide, silicon dioxide, beryllium oxide, titanium oxide, zirconium oxide, zinc oxide, etc. Metal oxides such as magnesium hydroxide, aluminum hydroxide, barium hydroxide, calcium hydroxide, etc.; metal carbides such as boron carbide, aluminum carbide, silicon carbide, etc. By using these thermally conductive fillers, high thermal conductivity can be imparted while being good in electrical insulation. Among them, alumina is more preferably used as the inorganic filler in the present invention. Such inorganic fillers are generally used in a ratio of about 5 to 300 parts by mass relative to 100 parts by mass of the thermosetting resin, preferably about 10 to 260 parts by mass, and more preferably about 15 to 120 parts by mass. use.

Further, the thermosetting resin composition of the present invention can be blended with various conventional additives in the range that does not impair the effect of the present invention in addition to the above-mentioned blending components, for example, a hardener, Release agents, tackifiers, pigments, flame retardants, stabilizers, UV absorbers, colorants, lubricants, coupling agents, etc.

In addition, among these additives, the hardening agent may, for example, be benzyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-bis(tertiary butylperoxy)hexane , 1,3-bis(tertiary butyl peroxypropyl) benzene, tertiary butyl peroxy-2-ethylhexyl monocarbonate, tertiary butyl peroxypropyl monocarbonate, tributyl peroxypropyl monocarbonate tertiary butyl peroxybenzoate, n-butyl-4,4-bis (tertiary butyl peroxy) valerate, 2,2-bis (tertiary butyl peroxy) butane, Conventional peroxides such as tertiary butyl cumene peroxide, and mold release agents include, for example, stearic acid, zinc stearate, calcium stearate, aluminum stearate, magnesium stearate, and palm wax (Carnauba wax) etc. Furthermore, as a thickener, magnesium hydroxide, calcium hydroxide, calcium oxide, an isocyanate compound, etc. are mentioned.

Here, the thermosetting resin composition of the present invention can be prepared by uniformly mixing the blending components using a device capable of dispersing under shearing force, such as a mixer, after preparing the blending components as described above. , the mixer specifically includes: a wet disperser using a medium, such as a ball mill, a sand mill, a bead mill, etc.; an ultrasonic disperser, such as a homogenizer; and a pressurized disperser, such as Ultimizer and the like. Next, using the obtained thermosetting resin composition, a molding step (first step) and a hardening step (second step) are used to obtain a desired molded product. Here, the curing step is performed simultaneously with the molding step, or in after the forming step. Further, before the forming step, a step of melt-kneading the mixture of the respective blending components (melt-kneading step) may also be employed as necessary.

In addition, as for the melt-kneading step used in the production of the molded product, a pressure kneader, a mixing roll, a biaxial extruder, etc. are used to heat, melt and knead the mixture of the above-mentioned various blending components, The obtained kneaded product is molded into a sheet shape, and the obtained sheet-shaped molded product is further granulated or pulverized using a granulator, PowerMill, or the like to form a pellet (molding material) of the thermosetting resin composition.

In addition, the method used in the forming step of forming the above-mentioned forming material is not particularly limited. For example, conventional forming methods such as injection molding, transfer injection molding, and compression molding can be appropriately used. Among them, the injection molding method is particularly suitable for using . In addition, when the injection molding method is used, the temperature of the front part of the injection cylinder is generally set to about 70℃~120℃, and the temperature of the rear part of the injection cylinder is generally about 30℃~60℃.

More specifically, although the molding material (thermosetting resin composition) is hardened in the hardening step, conventional methods such as heating are usually employed for the method. In addition, when this kind of heating and hardening is used, the heating temperature is generally about 150°C to 200°C, and the heating time is generally about 30 seconds to 90 seconds. In addition, when this hardening process is performed simultaneously with the said shaping|molding process, shaping|molding is performed so that the shaping|molding die (mold) used in this shaping|molding process may be heated to the said heating temperature.

Next, the molded product obtained through the above forming step and hardening step can be used in various applications such as automobile parts, electrical/electronic parts, building components, various containers, daily necessities, daily miscellaneous goods, and hygiene products. Shapes obtained by insert molding of parts are considered to be advantageous objects. This is because the metal insert molded product is likely to be cracked due to the difference in thermal expansion coefficient between metal and resin. Among them, the thermosetting resin composition according to the present invention is particularly advantageous for use in the manufacture of insert molded products, and is particularly suitable for use in the manufacture of metal insert molded products (metal-resin composite integrated products) having the following structure: Thereby, the excellent thermal shock resistance of the thermosetting resin composition according to the present invention can be advantageously exerted. The structure of the metal insert molding product is that the metal insert has an acute angle of about 90° or an angle less than 90°, And the metal insert including such an acute angle part is covered with resin. Example

Hereinafter, several embodiments of the present invention are shown and compared with comparative examples to further demonstrate the characteristics of the present invention, but the present invention is not restricted by the description of these embodiments, it goes without saying. In addition, it should be understood that the present invention, in addition to the following embodiments (further, together with the above-mentioned specific descriptions), can be implemented according to the knowledge of those skilled in the art without departing from the spirit of the present invention. knowledge to apply various changes, corrections, and improvements. In addition, unless otherwise stated, the percentages (%) and parts shown below are all expressed on a mass basis.

In addition, the measurement method of the content and physical property value of the raw material (blending component) used in the following Examples and Comparative Examples is as follows.

-Thermosetting resin- Unsaturated polyester resin: U-Pica 8523 manufactured by Japan U-Pica Co., Ltd. Diallyl phthalate resin: DAP A manufactured by OSAKA SODA CO., LTD. Phenolic resin: CP1006 (Novolak-type phenolic resin) manufactured by Asahi Organic Materials Co., Ltd. -Elastomer- Acrylonitrile butadiene rubber (NBR): PNC-38 manufactured by JSR Co., Ltd. -glass fiber- Glass fiber: CSG3PL-830S by Nitto Boseki Co., Ltd. (average fiber length: 3 mm) -carbon fiber- Pitch-based carbon fiber: K223HE manufactured by Mitsubishi Chemical Corporation (average fiber length: 3 mm) Pitch-based carbon fiber: K223HM manufactured by Mitsubishi Chemical Corporation (average fiber length: 50µm) -Inorganic filler- Alumina: ALM43 manufactured by Sumitomo Chemical Co., Ltd. (average particle size: 4 µm) Alumina: AL41-01 manufactured by Sumitomo Chemical Co., Ltd. (average particle size: 50µm) -hardener- Tertiary butyl peroxy isopropyl monocarbonate: PERBUTYL I manufactured by NOF Corporation -lubricant- Calcium stearate: product of NOF Corporation -pigment- Carbon black: MA100 manufactured by Mitsubishi Chemical Corporation

-Thermal cycle test- In the dimensions shown in FIG. 1 , a plurality of metal inserts 2 having an L-shaped corner with an angle of 90° without chamfering were used to produce a plurality of resin thicknesses from each thermosetting resin composition by injection molding. The resin coating layer of 2 mm and the insert-molded product 4 shown in FIG. 2 were used as the insert-molded product 4 test piece. In addition, the injection molding conditions were set as injection pot temperature: 70°C for the front part, 40°C for the rear part, mold temperature: 165°C, and curing time: 180 seconds.

Next, 10 obtained test pieces (4) were heated at 200°C for 10 minutes, held at 25°C for 10 minutes, and then cooled at -40°C for 10 minutes. The above process was regarded as one cycle and the operation was repeated 250 times. , 500 times or 1000 times, the test pieces (4) were visually observed to see whether or not cracks occurred, and evaluated according to the following criteria. ○: No crack was observed in any of the 10 test pieces. △: No cracks were observed in the test pieces with a ratio of 60% or more. ×: Cracks were observed in all 10 test pieces.

-Measurement of thermal conductivity- Using each thermosetting resin composition, a test piece having a size of 10 mm×10 mm×1 mm was produced by injection molding. In addition, the injection molding conditions were the same conditions as those of the test piece used for the above-mentioned thermal cycle test.

Next, about the obtained test piece, the thermal conductivity (W/m·K) in the thickness (1 mm) direction was measured by the xenon flash method using LFA447 manufactured by NETZSCH, Germany.

-Determination of bending strength- Using each thermosetting resin composition, a test piece having a size of 10 mm×80 mm×4 mm was produced by injection molding. In addition, the injection molding conditions were the same conditions as those of the test piece used for the above-mentioned thermal cycle test.

Next, with respect to the obtained test piece, a bending test was carried out with a precision universal testing machine (Autograph) manufactured by Shimadzu Corporation, and the maximum point at which the test piece was ruptured was determined as the bending strength (MPa).

-Determination of volume resistivity- Using each thermosetting resin composition, a test piece having a size of 10 mm×80 mm×4 mm was produced by injection molding. In addition, the injection molding conditions were the same conditions as those of the test piece used for the above-mentioned thermal cycle test.

Next, with respect to this obtained test piece, the volume resistivity was measured by the 4-deep needle method using Loresta GP MCP-T600 manufactured by Mitsubishi Chemical Corporation. In addition, it is generally accepted that the obtained sample with a volume resistivity less than 10 ⁶ Ωcm will be a semiconductor plastic, and a sample with a volume resistivity of more than 10 ⁶ Ωcm will become an electrical insulator.

(Examples 1 to 4) In the ratio shown in Table 1 below, blend thermosetting resin (unsaturated polyester resin), elastomer (NBR), glass fiber and hardener (PERBUTYL I), release agent (calcium stearate) and Pigment (carbon black) and mix well. Next, the obtained mixture is uniformly heated and kneaded with a hot roll, and then processed into a sheet shape. After cooling, it is pulverized with a PowerMill to obtain various molding materials in the form of granules.

Next, various test pieces were produced using these obtained molding materials, and a thermal cycle test was performed, while thermal conductivity, bending strength, and volume resistivity were measured, respectively, and the results are shown in Table 1 below.

[Table 1] blending ingredients type Example 1 Example 2 Example 3 Example 4 Blending composition (parts) Thermosetting resin Unsaturated polyester resin 100 100 100 100 Elastomer NBR 130 160 230 160 glass fiber Chopped Strands 270 270 270 150 hardener PERBUTYL I 4 4 4 4 other Calcium stearate + carbon black 33 33 33 33 Physical properties of molded products Thermal cycle test After 250 cycles 〇 〇 〇 〇 After 500 cycles △ 〇 △ △ After 1000 cycles △ △ △ △ Thermal conductivity (W/m·K) 0.3 0.3 0.3 0.3 Bending strength (MPa) 29 25 15 10 Volume resistivity (Ωcm) 1.0 x 10 ⁶ < 1.0×10 ⁶ < 1.0×10 ⁶ < 1.0×10 ⁶ <

From the results in Table 1, it can be clearly confirmed that the insert molded articles obtained from the thermosetting resin compositions of Examples 1 to 4 all have excellent molded article properties, and in particular, the insert molded articles that can be repeatedly subjected to multiple thermal cycles are provided. A molded product that effectively inhibits or even prevents cracks under thermal cycle tests.

(Examples 5 to 17) In addition to the blending components of the previous examples 1 to 4, carbon fibers (pitch-based) or inorganic fillers (alumina) are used together with them, and they are blended and uniformly mixed in the proportions shown in Tables 2 and 3 below. , and various molding materials in the form of granules were produced from the obtained mixture in the same manner as in the previous embodiment.

Next, various samples were produced using these obtained molding materials, and thermal cycle tests were performed to measure thermal conductivity, flexural strength, and volume resistivity, respectively. The results obtained are shown in Tables 2 and 3 below.

[Table 2] blending ingredients type Example 5 Example 6 Example 7 Example 8 Example 9 Example 10 Blending composition (parts) Thermosetting resin Unsaturated polyester resin 100 100 100 100 100 100 Elastomer NBR 160 160 160 160 160 160 glass fiber Chopped Strands 270 150 270 400 270 270 carbon fiber Pitch-based carbon fiber (average fiber length: 3mm) 125 230 230 230 230 230 Inorganic filler Alumina (average particle size: 4µm) - - - - 80 130 hardener PERBUTYL I 4 4 4 4 4 4 other Calcium stearate + carbon black 33 33 33 33 33 33 Physical properties of molded products Thermal cycle test After 250 cycles 〇 〇 〇 〇 〇 〇 After 500 cycles △ △ 〇 〇 〇 △ After 1000 cycles △ △ 〇 △ 〇 △ Thermal conductivity (W/m·K) 0.9 2.2 1.7 1.2 2.4 2.6 Bending strength (MPa) 50 30 44 59 47 47 Volume resistivity (Ωcm) 1.0×10 ⁶ < < 1.0×10 ⁶ < 1.0×10 ⁶ < 1.0×10 ⁶ < 1.0×10 ⁶ < 1.0×10 ⁶

[table 3] blending ingredients type Example 11 Example 12 Example 13 Example 14 Example 15 Example 16 Example 17 Blending composition (parts) Thermosetting resin Unsaturated polyester resin 100 100 100 100 100 95 95 Diallyl phthalate resin - - - - - 5 - Phenolic resin - - - - - - 5 Elastomer NBR 160 160 160 160 160 160 160 glass fiber Chopped Strands 270 270 270 270 270 270 270 carbon fiber Pitch-based carbon fiber (average fiber length: 3mm) 230 230 - - 200 230 230 Pitch-based carbon fiber (average fiber length: 50µm) - - 230 230 30 - - Inorganic filler Alumina (average particle size: 4µm) 260 20 - 80 80 80 80 Alumina (average particle size: 50µm) - 60 - - - - - hardener PERBUTYL I 4 4 4 4 4 4 4 other Calcium stearate + carbon black 33 33 33 33 33 33 33 Physical properties of molded products Thermal cycle test After 250 cycles 〇 〇 〇 〇 〇 〇 〇 After 500 cycles △ 〇 〇 〇 〇 〇 〇 After 1000 cycles △ 〇 〇 〇 〇 〇 〇 Thermal conductivity (W/m·K) 1.8 2.5 1.8 2.5 2.0 2.4 2.3 Bending strength (MPa) 44 43 41 41 42 50 39 Volume resistivity (Ωcm) < 1.0×10 ⁶ < 1.0×10 ⁶ < 1.0×10 ⁶ < 1.0×10 ⁶ < 1.0×10 ⁶ < 1.0×10 ⁶ < 1.0×10 ⁶

From the results in Tables 2 and 3, it can be clearly observed that the samples made from the thermosetting resin compositions obtained in Examples 5 to 17 all have excellent physical properties of molded articles, especially by blending carbon fibers, which can effectively improve thermal conductivity. At the same time, the volume resistivity can be advantageously reduced, and by blending carbon fibers and inorganic fillers, the thermal shock resistance can also be advantageously improved.

(Comparative Examples 1 to 7) In the same manner as in the above-mentioned Examples, various evaluation samples were prepared from the respective thermosetting resin compositions obtained under the blending compositions shown in Table 4 below, and thermal cycle tests were carried out to measure thermal conductivity, flexural strength, and volume resistivity, respectively. The obtained results are shown in Table 4 below.

[Table 4] blending ingredients type Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Blending composition (parts) Thermosetting resin Unsaturated polyester resin 100 100 100 100 100 95 100 Diallyl phthalate resin - - - - - 5 - Elastomer NBR 80 80 80 80 80 80 0 glass fiber Chopped Strands 270 150 80 270 270 270 90 carbon fiber Pitch-based carbon fiber (average fiber length: 3mm) - - - 230 230 - 80 Inorganic filler Alumina (average particle size: 4µm) - - - - 130 80 20 hardener PERBUTYL I 4 4 4 4 4 4 4 other Calcium stearate + carbon black 33 33 33 33 33 33 33 Physical properties of molded products Thermal cycle test After 250 cycles × × × × × × × After 500 cycles × × × × × × × After 1000 cycles × × × × × × × Thermal conductivity (W/m·K) 0.3 0.3 0.3 1.7 1.5 0.4 2.3 Bending strength (MPa) 35 14 11 48 75 50 125 Volume resistivity (Ωcm) 1.0×10 ⁶ < 1.0×10 ⁶ < 1.0×10 ⁶ < < 1.0×10 ⁶ < 1.0×10 ³ 1.0×10 ⁶ < < 1.0×10 ⁶

As is apparent from the results in Table 4, Comparative Example 7, which is a thermosetting resin composition not incorporating an elastomer, and the thermosetting resins of Comparative Examples 1 to 6 in which the amount of the elastomer blended is small are shown. In all of the compositions, significant cracks were observed in a thermal cycle test in which multiple thermal cycles were repeated, and it was judged that it was difficult to use them as a metal insert molded product in practice. Furthermore, it was also observed that thermal shock resistance could not be improved by adding carbon fibers or inorganic fillers alone.

2: metal inserts 4: Insert molding

FIG. 1 is an explanatory diagram showing an insert mold for insert molding in an embodiment: (a) is a front view, (b) is a right side view, and (c) is a bottom view. Fig. 2 is an explanatory view showing an insert molded product obtained by using the insert mold shown in Fig. 1: (a) is a front view, (b) is a right side view, and (c) is a bottom view.

(none)

Claims (17)

A thermosetting resin composition is characterized in that it is obtained by blending a thermosetting resin, an elastomer and a glass fiber, and is structured such that the content ratio of the elastomer/thermosetting resin is greater than 1.0 on a mass basis. The thermosetting resin composition according to claim 1, wherein the content ratio of the glass fiber/the aforementioned thermosetting resin is 1.0 or more and 5.0 or less on a mass basis. The thermosetting resin composition according to claim 1 or claim 2, which is blended with glass fibers in a ratio of 150 to 450 parts by mass and 120 to 250 parts by mass relative to 100 parts by mass of the aforementioned thermosetting resin. Made of elastomers. The thermosetting resin composition according to any one of claim 1 to claim 3, wherein the thermosetting resin is selected from unsaturated polyester resins and diallyl phthalate resins. The thermosetting resin composition according to any one of claim 1 to claim 4, wherein the aforementioned elastomer is acrylonitrile butadiene rubber. The thermosetting resin composition according to any one of claim 1 to claim 5, further incorporating carbon fibers. The thermosetting resin composition according to claim 6, wherein the content ratio of the carbon fiber/the thermosetting resin is 1.0 or more and 3.0 or less on a mass basis. The thermosetting resin composition according to claim 6 or claim 7, wherein the carbon fibers are blended in a ratio of 110 to 270 parts by mass relative to 100 parts by mass of the thermosetting resin. The thermosetting resin composition according to any one of claim 6 to claim 8, wherein the content ratio of the carbon fiber/the glass fiber is 0.2 or more and 1.0 or less on a mass basis. The thermosetting resin composition according to any one of claim 6 to claim 9, wherein the carbon fibers are pitch-based carbon fibers. The thermosetting resin composition according to any one of claim 1 to claim 10, further incorporating an inorganic filler. The thermosetting resin composition according to claim 11, wherein the inorganic filler is alumina. The thermosetting resin composition according to any one of claim 1 to claim 12, which is used for manufacturing a metal-resin composite integrated product. A metal-resin composite integrated product is obtained by insert molding using the thermosetting resin composition according to any one of claim 1 to claim 13 in the presence of a metal insert. A method for manufacturing a metal-resin composite integrated product, comprising: The first step is to perform insert molding using the thermosetting resin composition according to any one of claim 1 to claim 13 in the presence of a metal insert, whereby a predetermined thickness is formed on the surface of the metal insert. forming a coating layer composed of the thermosetting resin composition; and The second step is to harden the coating layer formed of the thermosetting resin composition. The method for manufacturing a metal-resin composite integrated product according to claim 15, wherein the second step is performed simultaneously with the first step or after the first step. The method for manufacturing a metal-resin composite integrated product according to claim 15 or claim 16, wherein the metal insert has a corner portion of 90° or less than 90°, and on the other hand, is formed such that the corner portion is heated by the heat It is covered with a coating layer composed of plastic resin.

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