JPS6376209A - 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.

[Open Points to be Solved by the Prior Art and the Invention] Conventionally, compositions made of liquid polybutadiene and polyisocyanate compounds containing water-unfriendly groups have been known as insulating materials for circuit boards, for example. Since it is a liquid composition, it can be 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.
When the hydride has a large number of 4-addition type skeletons, the hydride becomes solid and the fluidity necessary for potting and dipping materials cannot be obtained.On the other hand, when it has a large number of 1.2-addition type skeletons, the average The number of bases becomes small, and in both cases, the heat aging resistance remains unimproved, and specifically, there is a problem that the volume resistivity decreases after 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 extensive research in order to achieve the above object, the inventors of the present invention have developed a hydride of liquid polyisoprene having an isocyanate group instead of a hydride of liquid polybutadiene having a hydroxyl group. The present invention was completed by confirming that excellent effects can be obtained when the polyol compound is used in combination with a polyol compound and/or a polyamine compound.

That is, the electrical insulating material of the present invention is characterized in that it is made by curing a liquid polymer composition comprising a hydride of liquid polyisoprene containing an isocyanate group, and a polyol compound and/or a polyamine compound.

As described above, the electrical insulating material of the present invention comprises a composition comprising a hydride of liquid polyisoprene containing an isocyanate group (first essential component) and a polyol compound and/or a polyamine compound (second essential component). It is made by hardening.

First, a liquid polyisoprene hydride having isocyanate 2G, which is the first essential component, can be produced, for example, as follows. That is, first, liquid polyisoprene having hydroxyl groups is mixed with Ni, Co, Ru, Pt, Rh.
A hydrogenated product of liquid polyimprene containing water groups is obtained by hydrogenation in the presence of a commonly used hydrogenation catalyst such as the following. The liquid polyisoprene containing a hydroxyl group used at this time has a hydroxyl group within one molecule or at the end of the molecule, and has a number average molecular weight of 300 to 25,000. It is preferably 500 to 10,000, and the content of hydroxyl groups is usually 0, 1 to 10 meq/g, preferably 0.3 to 7 meq/g.

Next, by reacting the thus obtained hydride of liquid polyisoprene containing hydroxyl groups with a polyisocyanate compound, a hydride of liquid polyisoprene containing isocyanate groups can be obtained. The polyisocyanate compound used at this time is an organic compound having two or more isocyanate groups in one molecule, and has an isocyanate group reactive with the hydroxyl group of the hydride of the liquid polyisoprene containing the hydroxyl group. It is something. Examples of polyisocyanate compounds are the usual aromatics.

Mention may be made of aliphatic and cycloaliphatic ones, such as tolylene diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate) (MDI).
), liquid modified diphenylmethane diisocyanate, polymethylene polyphenylisocyanate, xylylene diisocyanate, cyclohexyl diisocyanate, cyclohexane phenylene diisocyanate, naphthalene
1,5-diisocyanate, isopropylbenzene-2
, 4-diisocyanate, addition reaction products of polypropylene glycol and tolylene diisocyanate, and particularly preferred are MDI, liquid modified diphenylmethane diisocyanate, tolylene diisocyanate, and the like.

Examples of the polyol compound and polyamine compound which are the second essential components include the following.

As the polyol compound, 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-bentanediol, 2,5-hexanediol, 2,4-hexanediol, 2-ethyl-1,3-hexanediol, Cyclohexanediol, glycerin, N,N-bis-2-hydroxypropylaniline, N,N''-bishydroxyisopropyl-
Examples include low molecular weight polyols containing a hydroxyl group bonded to at least one secondary carbon, such as 2-methylpiperazine and a propylene oxide adduct of bisphenol A.

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. . As the polyol, a diol is usually used, but a triol or a tetraol may also be used. In addition, a liquid diene polymer containing a hydroxyl group can also be used.

Further, the polyamine compound may be any of diamine, triamine, and tetraamine, and furthermore, any of primary polyamine, secondary polyamine, and tertiary polyamine may be used. Examples of polyamine compounds include aliphatic amines such as hexamethylene diamine; alicyclic amines such as 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane; aromatic amines such as 4,4'-diaminodiphenyl; Examples include tetramines such as 2,4,6-tri(dimethylaminomethyl)phenol.

The blending ratio of the above-mentioned first and second essential components is not particularly limited, but usually 5 parts of the polyol compound and/or polyamine compound are added to 100 fi parts of the isocyanate group-containing polyisoprene hydride.
The amount is set to 500 parts by weight, preferably 10 to 300 parts by weight.

Note that other additives may be added to this composition as desired. Specific examples 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 70% ma-based, naphthene-based, and paraffin-based oils are added, and alkylphenol resins, terpene resins, etc. are added to adjust adhesive strength and adhesive strength. Terpene 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 can be added to improve weather resistance, and a silicon compound or the like can 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 processing temperature at this time is 6 to 200'O
1 Preferably 15-150°C, treatment time 0.5-75°C
time, 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 an isocyanate group at the end of the molecular chain) 200 g of isoprene, concentration 5 was placed in a stainless steel pressure-resistant reaction vessel with an internal volume of 1 liter.
16 g of 0% hydrogen peroxide and ffec as a solvent
- Prepare 100g of butyl alcohol, temperature 120℃,
The reaction was carried out for 2 hours at a maximum pressure of 8 kg/cra 2 G. After the reaction was completed, the reaction solution was extracted, and 600 g of water was added to it.
was added, shaken in a separatory funnel, and left to stand for 3 hours. After separating the oil layer, it was distilled at 2 rrrtaHg and 100° C. for 2 hours to remove the solvent, monomer and low-boiling components to obtain liquid polyisoprene having a hydroxyl group at the end of the molecule. Yield: 11A 68%. The number average molecular weight of this liquid polyisoprene is 2150, and the hydroxyl group content is 0.96.
meq/g, and the viscosity was 56 boils 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-Cl0g was charged, and hydrogen was added to it at a pressure of 50
It was introduced at kg/c+w2G. The temperature at this time is 1
The reaction time at 40°C was 5 hours. After the reaction was completed, the reaction solution was extracted and filtered through a membrane filter (0,454) to remove the catalyst, and then the pressure was reduced to 2 mdg.
The solvent was distilled off at a temperature of 110° C. for 2 hours to obtain the desired hydrogenated liquid polyisoprene having a hydroxyl group at the end of the molecular chain. The number average molecular weight of the obtained hydride was 22
10, the hydroxyl group content was 0.94 meq/g, the iodine value was 1 or less, and the viscosity at 30°C was 383 voids.

Subsequently, 50 g of this hydride was charged into a separable flask with an internal volume of 300 -, and 15.8 g of tolylene diisocyanate was added thereto and reacted at 25°C for 2 hours.
By reacting at 70° C. for 4 hours, a hydrogenated liquid polyisoprene having an isocyanate group at the end of the molecular chain was obtained. This product had an isocyanate group (NGO group) base fabric content of 93% by weight, and a viscosity at 30° C. of 573 voids.

Production Example 2 (Production of hydride of 1,4-addition type liquid polybutadiene having a hydroxyl group at the end of the molecular chain) As a 1,4-addition type liquid polybutadiene having a hydroxyl group at the end of the molecular chain, R-45HT manufactured by Idemitsu Arco ■ was used. (Number average molecular weight: 2
800, OH content: Q, 82 meq/g,
Viscosity at 30° C.: 50 poise, 1.4-addition type skeleton: 80 mol%, 1.2-addition type skeleton = 20 mol%) was used, and this was hydrogenated to obtain a hydride. The conditions for this hydrogenation were that the reaction time was 4.5 hours, and 500ml of toluene was added after the reaction was completed.
was set in the same way. The number average molecular weight of the obtained hydride was 2920.0, the H content was 0.80 meq/g, and it was a waxy solid.

Production Example 3 (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 Co., Ltd. as a 1,2-addition type liquid polybutadiene having a hydroxyl group inside the molecular chain (Number average molecular weight: 2,000, OH content rJ-: 0, 85
meq/g.

A hydride was obtained by hydrogenation in exactly the same manner as in Production Example 1 using a 30" C viscosity: 1930 poise). The obtained hydride had a number average molecular weight of 2.080, an 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 38 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 description, the electrical insulating material of the present invention has good fluidity before hardening, has excellent electrical insulating properties after hardening, and It also has excellent thermal fatigue resistance. 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. 219211 of 19882, Title of invention Idemitsu Petrochemical Co., Ltd.4, Agent5, Order for amendment Date of publication 6, Subject of amendment Detailed explanation of the invention in the specification column 7,
811m1oα Line 5 of the amendment details: "The electrically insulating material of the present invention is particularly suitable for use in electronic circuits, insulating materials for substrates of electrical circuits, and moldings for transformers or transformers." It is useful as a molding material for connecting parts of cables, etc., and as an impregnating casting material for transformers or coils, especially.

Claims (2)

[Claims] (1) An electrical insulating material characterized by being made by curing a liquid polymer composition comprising a hydrogenated liquid polyisoprene containing an isocyanate group and a polyol compound and/or a polyamine compound. (2) The electrically insulating material according to claim 1, wherein the electrically insulating material is an insulating material for electronic circuit boards.