JPH0129208B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a thermosetting resin composition, and its purpose is to provide a thermosetting resin composition whose cured product has excellent electrical properties, film hardness, mechanical strength, dimensional accuracy, etc. for use in film capacitors, etc. is to provide. Film capacitors are made by sandwiching electrodes with polyester film, polypropylene film, styrene film, etc., and winding them together to prevent moisture.
For the purpose of insulation protection, a protective film is formed using a thermosetting resin composition, etc., in order to improve the stability of electrical properties, moisture resistance, and strength of mechanical properties. However, in response to the recent movement to improve the performance and reliability of electronic and electrical equipment, for example, in fields such as audio equipment, communication equipment, televisions, and video tape recorders, the temperature dependence of the dielectric loss tangent and capacitance of film capacitors used has increased. It is required that there be as little sex as possible. At the same time, in response to the trend toward improved productivity, parts such as film capacitors are being automatically attached to circuit boards. They are required to be excellent. Epoxy resin compositions conventionally used as impregnating agents and coating agents for film capacitors have the disadvantage that the dielectric loss tangent and capacitance change greatly depending on the temperature of the atmosphere in which they are used, and that the dielectric loss tangent changes significantly at high temperatures. Furthermore, film capacitors coated with a high viscosity epoxy resin composition having thixotropy have uneven coating thickness and poor dimensional accuracy. Furthermore, although polybutadiene resin has excellent temperature dependence and dimensional accuracy for film capacitors, it has the disadvantage that the film is soft and easily damaged, and the tensile strength of the lead wire during automatic insertion of the capacitor is weak. The present inventors have discovered a thermosetting resin composition that is easily cured by the addition of an organic peroxide, and the cured product exhibits characteristics of low dielectric loss tangent and dielectric constant, and excellent mechanical strength. A film capacitor treated with the resin composition of the present invention has excellent tensile strength and dimensional accuracy. The present invention comprises a terminal acrylic-modified 1,2-polybutadiene resin or a terminal methacrylic-modified 1,2-polybutadiene resin (1) dicyclopentadiene and maleic acid, (2) dicyclopentadiene, maleic anhydride and water or (3) Unsaturated polyester obtained by condensation reaction of partially esterified dicyclopentadiene carboxylic acid obtained by reacting hydroxylated dicyclopentadiene and maleic anhydride at 150°C or lower with a polyhydric alcohol ()
The present invention also relates to a thermosetting resin composition containing a styrene compound or a polyfunctional methacrylic acid ester. In the present invention, terminal methacrylic modified 1,2
- A polybutadiene resin such as NISSO-PB (trade name) TE-2000 manufactured by Nippon Soda Co., Ltd. or a terminally acrylic-modified 1,2-polybutadiene resin is used. These are resins in which the main bonds in the polymer chain are 1,2-bonds, for example, 90% or more. The unsaturated polyester used in the present invention is obtained by valence condensation of partially esterified dicyclopentadiene carboxylic acid and polyhydric alcohol. It is obtained by reacting an acid, (2) dicyclopentadiene, maleic anhydride and water or (3) hydroxylated dicyclopentadiene and maleic anhydride. In this reaction, an addition reaction between dicyclopentadiene or hydroxylated dicyclopentadiene and the primary carboxyl group of maleic acid or maleic anhydride occurs at temperatures below 150°C due to the strong dissociative nature of the primary carboxylic acid of maleic acid. , a partially esterified dicyclopentadiene carboxylic acid is obtained. The mixing ratio of dicyclopentadiene and maleic acid is preferably equimolar, preferably 150°C or less, preferably 120°C or less.
Reacted at a temperature of 140 °C, dicyclopentadiene,
It is preferable that the mixing proportions of maleic anhydride and water are equimolar, and the reaction is carried out at a temperature of 150°C or lower, preferably 120 to 140°C. Similarly, the mixing ratio of hydroxylated dicyclopentadiene and maleic anhydride is also equal. Molar is preferred and the reaction is carried out at a temperature below 150°C, preferably from 100 to 120°C to obtain partially esterified dicyclopentadiene. If the temperature exceeds 150°C, dicyclopentadiene will decompose into cyclopentadiene, so the reaction temperature should be kept below 150°C. Partially esterified dicyclopentadiene carboxylic acid can be treated as a raw material for polyester like monovalent carboxylic acid, and can be used as a raw material for polyester, such as ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, 1,3-butylene glycol, neopentyl glycol,
An unsaturated polyester can be obtained by a condensation reaction with a polyhydric alcohol such as 1,6-hexanediol. The blending ratio of partially esterified dicyclopentadiene and polyhydric alcohol is usually at an alcohol excess of 0.
The amount is preferably 1 mol of polyhydric alcohol to 2 mol of partially esterified dicyclopentadiene carboxylic acid. The reaction temperature is preferably 150~
It is said to be 210℃. In the production of unsaturated polyester, normally employed conditions are employed, and there are no particular limitations. Examples of the styrenic compound in the present invention include styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene,
Examples include dimethylstyrene, ethylstyrene, p-tertiary styrene, chlorostyrene, and divinylbenzene. In addition, as a polyfunctional methacrylic ester,
Ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, neopentyl glycol dimethacrylate, 1,3-butanediol dimethacrylate, dipropylene glycol dimethacrylate, polypropylene glycol dimethacrylate, trimethylolethane trimethacrylate, trimethylolpropane Trimethacrylate, tetramethylolmethanetetramethacrylate, etc. are used. The styrene compound and the polyfunctional methacrylic ester may be used together. When the thermosetting resin composition of the present invention is used as an impregnating agent or coating agent for a film capacitor, the above polybutadiene resin should be used in an amount of 10 to 60 parts by weight, and the above unsaturated polyester should be in an amount of 90 to 40 parts by weight. Use so that the total amount is 100 parts by weight,
It is preferable to use a styrene compound or a polyfunctional methacrylic acid ester in an amount of 40 to 110 parts by weight. Curing properties and pot life can be adjusted by adding a curing agent, a curing accelerator, and a polymerization inhibitor to the thermosetting resin composition of the present invention, if necessary. As the curing agent, any curing agent for unsaturated polyester resins can be used, such as methyl ethyl ketone peroxide, benzoyl peroxide, cyclohexanone peroxide,
t-butyl perbenzoate, 1,1-bis(t
-butylperoxy) 3,3,5-trimethylcyclohexane, cumene hydroperoxide, etc. are used. As the curing accelerator, cobalt naphthenate, cobalt octenoate, manganese naphthenate, cobalt acetylacetonate, dimethylaniline, etc. are used. As the polymerization inhibitor, hydroquinone, parabenzoquinone, catechol, diphenylquinone, etc. are used. In the thermosetting resin composition of the present invention, pigments, dyes, thixotropic agents, etc. may be used as necessary. When a terminal acrylic-modified 1,2-polybutadiene resin or a terminal methacrylate-modified 1,2-polybutadiene resin and a styrene compound or polyfunctional methacrylic acid ester are used as a crosslinking agent, the cured resin is soft and has poor mechanical strength. Therefore, for example, a film capacitor treated with this method has the disadvantage that the film is easily damaged and the tensile strength of the lead wire is weak when automatically inserting the capacitor. In the present invention, by further using the above-mentioned unsaturated polyester, the film hardness is hard, and when a film capacitor is treated with this, the tensile strength of the lead wire of the treated film capacitor is also improved. Examples of the present invention will be described. Parts are by weight. Production of unsaturated polyesters (A) to (D) 264 parts of dicyclopentadiene, maleic anhydride
196 parts and 36 parts of water were reacted at 140°C for 2 hours in a nitrogen gas stream to synthesize partially esterified dicyclopentadiene carboxylic acid, to which 83.6 parts of propylene glycol was added and a dehydration condensation reaction was carried out at 120°C for 10 hours. An unsaturated polyester (A) having an acid value of 10 was obtained. 300 parts of hydroxylated dicyclopentadiene and 196 parts of maleic anhydride were heated at 120°C in a nitrogen gas stream.
to synthesize partially esterified dicyclopentadiene carboxylic acid, to which 83.6 parts of propylene glycol was added, and a dehydration condensation reaction was carried out at 210°C for 10 hours to form an unsaturated polyester with an acid value of 10.
I got (B). 264 parts of dicyclopentadiene, maleic anhydride
196 parts and 36 parts of water were reacted at 140°C for 2 hours in a nitrogen stream to synthesize partially esterified dicyclopentadienecarboxylic acid, to which 118.0 parts of 1,6-hexanediol was added, and the mixture was reacted at 210°C for 10 hours. A dehydration condensation reaction was performed to obtain an unsaturated polyester (C) with an acid value of 10. 167.2 parts of propylene glycol was added to 98 parts of maleic anhydride and 196 parts of phthalic anhydride, and a dehydration condensation reaction was carried out at 210°C for 10 hours in a nitrogen stream to determine the acid value.
15 unsaturated polyester D was obtained. Examples 1 to 4 The compositions shown in Table 1 were mixed uniformly at room temperature, their compatibility was examined, and the hardness upon curing, pencil hardness, and bending strength were measured, and the results are shown in Table 1. . A film capacitor was treated with this composition, and the capacitor properties and tensile strength of the capacitor were measured. The results are shown in Table 1. Hardness, pencil hardness, and bending strength are improved by adding unsaturated polyester (A), and the tensile strength of the capacitor is also increased. The temperature characteristics of the capacitor are also excellent, with little change even when unsaturated polyester (A) is added. Example 5 The same tests as in Examples 1 to 4 were conducted using the compositions shown in Table 1, and the results are shown in Table 1. Hardness, pencil hardness, and bending strength are unsaturated polyester (B)
The tensile strength of the capacitor has also increased. The temperature characteristics of the capacitor are also excellent, with little change even when unsaturated polyester (B) is added. Example 6 The same tests as in Examples 1 to 4 were conducted using the compositions shown in Table 1, and the results are shown in Table 1. hardness,
Pencil hardness and bending strength are improved by adding trimethylolpropane trimethacrylate, and the tensile strength of the capacitor is also increased.
The temperature characteristics of the capacitor are also excellent due to the addition of trimethylolpropane trimethacrylate. Examples 7 to 10 The same tests as in Examples 1 to 4 were conducted using the compositions shown in Table 1, and the results are shown in Table 1. hardness,
Pencil hardness and bending strength are improved by adding trimethylolpropane trimethacrylate.
The tensile strength of capacitors is also increasing. The temperature characteristics of the capacitor are also excellent due to the addition of trimethylolpropane trimethacrylate. Comparative Example 1 The same tests as in Examples 1 to 4 were conducted using the compositions shown in Table 1, and the results are shown in Table 1. hardness,
The pencil hardness and bending strength are inferior to those of the examples, and the tensile strength of the capacitor is also low. Comparative Example 2 When the compositions shown in Table 1 were mixed uniformly at room temperature, the terminal methacrylic modification 1,
2-Polybutadiene resin and unsaturated polyester (D)
Phase separation occurred, and a composition for film capacitors could not be obtained.

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[Table] Hardness was measured by pouring 10 g of the composition into a metal shear dish with a diameter of 60 mm, curing it for 1 hour, and then measuring it at 25° C. using a Shor D hardness meter. To measure pencil hardness, pour the composition onto a tin plate, suspend it vertically, cure for 1 hour, and then apply it from B to 9H at 25℃.
The hardness of the film was measured when a crack occurred by rubbing the film with a pencil. The bending strength was determined by injecting and hardening the composition into a grooved metal mold of 127 x 12 x 5 mm. After curing for 1 hour, the test piece was taken out from the mold, thoroughly polished, and a Shimadzu Autograph (model IM) was used. -100), the bending strength was measured at 25°C. The capacitor characteristics were determined by immersing a 0.001 μF Mylar capacitor in the composition, soaking it for 3 minutes under a reduced pressure of 20 to 10 mmHg, then pulling it up at normal pressure, and heating and curing it in a curing oven at 120°C for 1 hour. The dielectric loss tangent, electrostatic loss tangent, and capacitance (C) were determined using Yokogawa Electric Corporation's 4260A), and the capacitance change rate at each temperature was determined using the following formula. Capacitance change rate (ΔC/C) (%) = (Ct℃−C25
℃) × 100/C ₂₅ ℃ The tensile strength of the capacitor is
A 0.001 μF capacitor is immersed in the composition and 20-10
After being impregnated for 3 minutes under a reduced pressure of mmHg, the sample was pulled up to normal pressure and cured by heating at 120°C for 1 hour, and the tensile strength between the lead wire and the capacitor was measured using a Schopper tester. The thermosetting resin composition of the present invention is easily cured, and the cured product thereof has a small dielectric loss tangent and a small dielectric constant, and exhibits excellent mechanical strength. When a film capacitor is treated using the thermosetting resin composition of the present invention, the resin film of the film capacitor is hard and will not be damaged even if it comes into contact with other elements, and the mechanical strength of the film is improved. It has the advantage that the tensile strength of the capacitor is greatly improved, and the problems of bending and damage during automatic insertion of the capacitor can be improved.

Claims (1)

[Claims] 1 Terminal acrylic-modified 1,2-polybutadiene resin or methacrylic-terminated 1,2-polybutadiene resin (), (1) dicyclopentadiene and maleic acid, (2) dicyclopentadiene, maleic anhydride, and water, or (3) Unsaturated polyester () and styrenic compound obtained by condensation reaction of partially esterified dicyclopentadiene carboxylic acid obtained by reacting hydroxylated dicyclopentadiene and maleic anhydride at 150°C or less and a polyhydric alcohol, or A thermosetting resin composition containing a polyfunctional methacrylic acid ester.