JPS6376208A - Electrically insulating material - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an electrically insulating material, and more particularly to an electrically insulating material having excellent heat aging resistance.

[Prior Art and Problems to be Solved by the Invention] Conventionally, compositions made of liquid polybutadiene and polyisocyanate compounds containing hydroxyl groups have been known as insulating materials for circuit boards, for example. Because it is a product, it is used, for example, as a so-called botting material that is cast onto a printed circuit board, or as a so-called dipping material that is immersed in a printed circuit board, and then
It is common to obtain an insulating material by curing.

However, electrical insulating materials made of the above-described compositions have the disadvantage of poor weather resistance and heat aging resistance.

Therefore, it has been proposed to use a hydride of this polybutadiene in place of the liquid polybutadiene. When such a liquid polybutadiene hydride is used, the weather resistance of the resulting insulating material is improved to some extent, but the following problems arise due to the skeleton of polybutadiene, which is the raw material for this hydride. That is, polybutadiene is 1.4
- When the hydride has a large number of addition-type skeletons, the hydride becomes solid and the fluidity necessary for botting and dipping materials cannot be obtained; becomes small, and in either case, the heat aging resistance remains unimproved, and specifically, there is a problem that the volume resistivity decreases after the heat history.

The purpose of the present invention is to solve these conventional problems and provide an electrical insulating material that has good fluidity as a botting material and dipping material before curing, and has excellent heat aging resistance after curing. shall be.

[Means for Solving the Problems] As a result of intensive research to achieve the above object, the present inventors have found that excellent effects can be obtained when a hydride of liquid polyisoprene is used in place of a hydride of liquid polybutadiene. The present invention was completed after confirming that the following could be obtained.

That is, the electrical insulating material of the present invention is characterized in that it is formed by curing a liquid polymer composition comprising a hydroxyl group-containing liquid polyisoprene hydride and a polyisocyanate compound.

As mentioned above, the electrical insulating material of the present invention is made by curing a composition consisting of a hydride of liquid polyisoprene containing hydroxyl groups (first essential component) and a polyisocyanate compound (second essential component). It is.

First, the liquid polyisoprene containing a hydroxyl group in the first essential component is a liquid polyisoprene having a hydroxyl group within the molecule or at the end of the molecule and having a number average molecular weight of 300 to 25,000, preferably 500 to 10,000. is used. Here, the content of hydroxyl groups is usually 0.1 to 10
tseq/g, preferably 0.3 to 7 eq/g.

Such liquid polyisoprene can be produced, for example, by subjecting isoprene to a heating reaction in a liquid reaction medium in the presence of hydrogen peroxide.

Furthermore, the liquid polyisoprene containing hydroxyl groups obtained in this way was mixed with Ni, Co, and Ru.

By hydrogenating in the presence of a commonly used hydrogenation catalyst such as Pt or Rh, a hydride of liquid polyisoprene containing hydroxyl groups, which is the first essential component of the composition of the present invention, is obtained.

Next, the polyisocyanate compound, which is the second essential component, is an organic compound having two or more incyanate groups in one molecule, and the polyisocyanate compound is an organic compound having two or more incyanate groups in one molecule. It has a reactive isocyanate group. Examples of polyisocyanate compounds include the usual aromatic, aliphatic and cycloaliphatic ones, such as tolylene diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate (MDI), liquid modified diphenylmethane diisocyanate, polymethylene poly Phenyl incyanate, xylylene diisocyanate, cyclohexyl diisocyanate, cyclohexane phenylene diisocyanate, naphthalene-1゜5-
Diisocyanate, isopropylbenzene-2,4-diisocyanate, polypropylene glycol and tolylene diisocyanate addition reaction productfp)/a<g-t+1-
II! l+vnTaf44''7mM←?Futunylmethane diisocyanate, tolylene diisocyanate, etc. are preferable.

The blending ratio of the first and second essential components described above is not particularly limited, but usually the incyanate group (NGO) of the polyisocyanate compound is
) (NCOloH) in a molar ratio of 0.2 to 25, preferably 0.5 to 15.

In addition, a polyol compound or a polyamine compound can be added to such a composition as a reinforcing agent if desired.
Furthermore, various other additives can be added.

As a polyol compound that may be added as desired.

Any of primary polyol, secondary polyol, and tertiary polyol may be used. Specifically, for example, 1,2-propylene glycol, dipropylene glycol, 1,2-butanediol, 1,3-butanediol, 2 .3-butanediol, 1.2-bentanediol, 2.3-pentanediol, 2.5-hexanediol, 2.4-hexanediol, 2-ethyl-1,3-hexanediol, cyclohexanediol, glycerin, Low-carbon compounds containing a hydroxyl group bonded to at least one secondary carbon, such as N,N-bis-2-hydroxypropylaniline, N,N'-bishydroxyisopropyl-2-methylbiperazine, and propylene oxide adduct of bisphenol A. Mention may be made of molecular weight polyols.

Furthermore, ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-bentanediol, 1,6-hexanediol, etc. that do not contain a hydroxyl group bonded to a secondary carbon can also be used as the polyol. . Diols are usually used as polyols, but triols and tetraols may also be used, and their molecular weights range from 50 to 500.

Further, the polyamine compound may be any of diamine, triamine, and tetraamine.

Furthermore, any of primary polyamine, secondary polyamine, and tertiary polyamine can be used. Examples of polyamine compounds include aliphatic amines such as hexamethylene diamine, alicyclic amines such as 3.3''-dimethyl-4,4'-diaminodicyclohexylmethane, and aromatic amines such as 4,4'-diaminodiphenyl; Examples include tetramines such as 2,4,6-tri(dimethylaminomethyl)phenol.

When blending these polyol compounds or polyamine compounds, there is no particular restriction on the blending ratio, but usually 1 part of the polyol compound or polyamine compound is added to 100 parts by weight of the above-mentioned liquid polyimprene containing the present invention group.
~1000 parts by weight.

Preferably, 3 to 200 parts by weight is blended.

Further, other additives that may be added as desired include fillers such as mica, graphite, vermiculite, calcium carbonate, and slate powder.

Furthermore, plasticizers such as dioctyl phthalate are added as viscosity modifiers, softeners such as aromatic, naphthenic, and paraffin oils are added, and alkylphenol resins, terpene resins, and terpene resins are added to adjust the adhesive strength. Phenol resin, xylene formaldehyde resin,
Tackifying resins such as rosin, hydrogenated rosin, coumaron resins, aliphatic and aromatic petroleum resins can also be added. Further, curing accelerators such as dibutyltin dilaurate, stannous octoate, polyethylene diamine, etc. can also be added. Furthermore, an anti-aging agent may be added to improve weather resistance, and a silicon compound or the like may be added as an antifoaming agent.

Furthermore, the electrical insulating material of the present invention can be manufactured by curing the liquid polymer composition obtained in this way. The treatment temperature at this time is set to 0 to 200°C, preferably 15 to 150°C, and the treatment time is set to 0.5 to 75 hours, preferably 1 to 70 hours.

[Function] Since the liquid polymer composition thus obtained has excellent fluidity, it can be cast on a substrate and then cured, or after the substrate is immersed in this composition. The electrically insulating region can be formed on the substrate by curing or the like. Therefore, the electrically insulating material of the present invention is particularly useful as an insulating material for electronic circuit boards.

[Example] Production Example 1 (Production of hydride of liquid polyisoprene having a hydroxyl group at the end of the molecular chain) In a stainless steel pressure-resistant reaction vessel with an internal volume of 1M, 200 g of isoprene, 16 g of hydrogen peroxide solution with a concentration of 50% by weight, and as a solvent were placed. Prepare 100g of 5ec-butyl alcohol,
2 at a temperature of 120°C and a maximum pressure of 8kg/cm”G
After 0 hours of reaction, the reaction solution was taken out, 600 g of water was added thereto, and the mixture was shaken with a separatory funnel and allowed to stand for 3 hours. After separating the oil layer, it was heated at 21Hg and 100℃ for 2
Time distillation was performed to remove the solvent, monomer, and low point components to obtain liquid polyisoprene having hydroxyl groups at the molecular ends. The yield was 68%. In addition, the number average molecular weight of this liquid polyisoprene is 2150, and the hydroxyl group content is 0.96 m
eq/g, and the viscosity was 56 voids at 30°C.

Next, 100 g of the liquid polyisoprene having a hydroxyl group at the end of the molecular chain obtained above was placed in the reaction vessel described above, and 100 g of cyclohexane as a solvent and 5 wt of a catalyst were added.
%Ru-Clog and hydrogen was added to it at a pressure of 50
It was introduced at kg/cm2G. The temperature at this time was 14
After the reaction was completed, the reaction solution was extracted at 0°C and the reaction time was 5 hours.
The solvent was distilled off at a temperature of 110° C. for 2 hours to obtain a liquid polyisoprene hydride having a hydroxyl group at the end of the molecular chain. The number average molecular weight of the obtained hydride was 2210
The hydroxyl group content was 0.94 meq/g, the iodine value was 1 or less, and the viscosity at 30°C was 383 poise.

Production Example 2 (Production of hydride of liquid polyisoprene having a hydroxyl group at the end of the molecular chain) The amount used was 50 g of dispersed hydrogen water with a concentration of 50% by weight.
A liquid polyisoprene having a hydroxyl group at the end of the molecular chain was obtained in the same manner as in Production Example 1 above, except that the amount of 5ec-butyl alcohol used was 300 g, the reaction temperature was 115 ° C., and the reaction time was 2.5 hours. Ta. The number average molecular weight of this product is 1380, and the hydroxyl group content is 1.39 tseq/g.
The viscosity at 30° C. was 23 poise.

Next, hydrogenation was performed under the same conditions as in Production Example 1 above to obtain a hydride. The number average molecular weight of this product is 1450, the hydroxyl group content is 1.38 meq/g, the iodine value is 1 or less,
The viscosity at 30°C was 248 voids. Production Example 3 (Production of hydride of 1,4-addition type liquid polybutadiene having a hydroxyl group at the end of the molecular chain) 1,4-Addition type liquid polybutadiene having a hydroxyl group at the end of the molecular chain As polybutadiene, manufactured by Idemitsu Arco (Incorporated), R-45HT (number average molecular weight: 2800, OH content: 0.82 meq/g, 30
Viscosity at °C: 50 poise, l, 4-addition skeleton = 8
0 mol %, 1.2-addition type skeleton: 20 mol %) was used, and this material was hydrogenated to obtain a hydride. The conditions for this hydrogenation were the same as in Production Example 1 above, except that the reaction time was 4.5 hours and 5,000 ml of toluene was added after the reaction was completed. The number average molecular weight of the obtained hydride was 29
20, the OH content was 0.80 meq/g, and it was a waxy solid.

Production Example 4 (Production of hydride of 1,2-addition type liquid polybutadiene having a hydroxyl group inside the molecular chain) Nl5SOPB G-2000 manufactured by Nippon Soda ■ as a 1,2-addition type liquid polybutadiene having a hydroxyl group inside the molecular chain (Number average molecular weight: 2,000, OH content: 0.85 m5q/g
, viscosity at 30° C.: 1930 poise), hydrogenation was carried out in exactly the same manner as in Production Example 1 to obtain a hydride. The obtained hydride had a number average molecular weight of 2.080 and O
The H content is 0.84 meq/g, it is a highly viscous liquid, and the B
It was not possible to measure the viscosity at 30°C using a type viscometer.

Examples 1 to 3 and Comparative Examples 1 to 3 The indicated components were collected into containers in the indicated amounts and stirred at 25° C. for 2 minutes to prepare liquid polymer compositions. Then,
The electrical insulating material of the present invention was obtained by injecting this composition into a mold and press hardening it at 120° C. for 1 hour.

The volume resistivity and elongation at 25°C were measured for each of the electrically insulating materials obtained. In addition, in order to examine the heat aging resistance, physical properties were measured after the heat aging test, and the results are shown in the table.

[Effects of the Invention] As is clear from the above explanation, the electrical insulating material of the present invention has good fluidity before curing, has excellent electrical insulating properties after curing, and has excellent heat resistance. It also has excellent fatigue properties. Therefore, it is useful as a botting material or dipping material, especially as an insulating material for electronic circuit boards, and its industrial value is extremely large.

Procedural amendment September 8, 1988 Kunio Ogawa, Commissioner of the Patent Office1, Indication of the case Patent Application No. 219210 of 19882, Name of the invention Relationship to the case Name of patent applicant Idemitsu Petrochemical Co., Ltd.4 , Agent 5, Date of amendment order Initiator 6, Subject of amendment Detailed explanation of the invention in the specification column 7, Contents of amendment ``The electrical insulating material of the present invention is In particular, the electrical insulating material of the present invention can be used as an insulating material for substrates of electronic circuits or electric circuits, a molding material for transmissions or transformers, a molding material for connections of cables, etc., and an impregnated casting material for transformers or coils. It is useful as a material, especially as a material.''

Claims (2)

[Claims] (1) An electrical insulating material characterized by being made by curing a liquid polymer composition comprising a hydride of liquid polyisoprene containing hydroxyl groups and a polyisocyanate compound. (2) The electrically insulating material according to claim 1, wherein the electrically insulating material is an insulating material for electronic circuit boards.