JPH0356564A - Silicone composition - Google Patents

Abstract

PURPOSE:To obtain a composition preferentially undergoing coordinate bond to metal part and preventing contact fault before occurrence of contact fault caused by adhesion of silica generated by spark of electric contact part to the metal part by adding a specific organic compound to organopolysiloxane. CONSTITUTION:100 pst. wt. organopolysiloxane composition is 0.01-15 pts. wt. organic compound capable of coordinating to a metal. An organic compound having 50-300 deg.C boiling point may be used as the organic compound and an ether such as anisole or diglyme, styrene, lactone, etc., can be used.

Description

DETAILED DESCRIPTION OF THE INVENTION <<Industrial Application Field>> The present invention relates to an organopolysiloxane composite, and more particularly to a silicone composite that can prevent contact failure. <Prior Art> Conventionally, various rubber materials and greases have been used as insulating materials around electrical and electronic contact members, and silicone-based materials are particularly frequently used due to their heat resistance and electrical properties. However, since silicone-based materials contain volatile low-molecular-weight siloxanes in the organopolysiloxane, which is the main polymer that forms the structure, these low-molecular-weight siloxanes volatilize and are generated at the contact points. The spark combusts to form silicon dioxide. This has the disadvantage that the contact portion becomes insulated, causing a so-called contact failure in which the motor circuit, relay circuit, etc. no longer perform their original functions. <<Problems to be Solved by the Invention>> The present inventors have conducted various studies on silicone materials that do not cause contact failure when used as an insulating material around electrical and electronic contact members, and have found that they can be used as main polymers. For silicone composites using organoborisiloxane,
The present invention was achieved by discovering the fact that the above-mentioned contact failure can be prevented by adding a small amount of an organic compound capable of forming a coordination compound with a metal.

Therefore, an object of the present invention is to provide a silicone material suitable for use as an insulating material around electrical and electronic contact members and which does not cause contact failure. <Means for Solving the Problems> The above-mentioned object of the present invention is to provide
00 parts by weight and 0.00 parts by weight of an organic compound capable of coordinating with a metal.
01 to 15 parts by weight have been achieved by certain silicone substances.

Contact failure can be prevented by adding a small amount of an organic compound that can form coordination compounds with metals to the silicone composition. The reason why this is possible is thought to be as follows. Generally, sparks generated at electrical contacts cause
The silica produced by the combustion of low-molecular-weight siloxane forms an insulating film, which causes contact failure, causing motor rotation/stoppage, relay malfunction, etc. However, if an organic compound with coordination ability is present in the metal, This is thought to be due to the fact that organic compounds are preferentially adsorbed and coordinated to the fresh metal surface of the contact area, which then prevents the adsorption and adhesion of silica, which is then adsorbed. The organoborisiloxane composition that forms the silicone composition of the present invention is not particularly limited, and examples include organoborisiloxane compositions that are vulcanized with organic peroxides, as detailed below. The organopolysiloxane composition can be appropriately selected from conventionally known organopolysiloxane compositions, such as curable compositions, reduced plate type curable compositions, platinum addition-curable compositions, radiation curable compositions, and grease compositions.

The reduced table type organopolysiloxane composite bottom is manufactured by Keigumi Weibu R. SiO. ．． It mainly contains a diorganopolysiloxane represented by L 2 . R in the formula is an alkyl group such as a methyl group, an ethyl group, a probyl group, a butyl group, a 2-ethylbutyl group, an octyl group, a cycloalkyl group such as a cyclohexyl group or a cyclopentyl group, an alkenyl group such as a vinyl group or a hexenyl group, phenyl group, tolyl group, xylyl group, naphthyl group,
Aryl groups such as diphenyl groups, aralkyl groups such as benzyl groups and phenylethyl groups, or chloromethyl groups in which some or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with halogen atoms, cyano groups, etc. The same or different unsubstituted or substituted monovalent hydrocarbon groups selected from fluoroprobyl group, 2-cyanoethyl group, 3-cyanoprobyl group, etc., and a is 1.90 to 2.05.
It is. Particularly in the case of the reduced table type, it is necessary to block the molecular chain ends with hydroxyl groups, but in particular, in order to show good rubber properties and have excellent mechanical strength,
It is required that the viscosity at 25°C be 25 cs or more. In addition, examples of the crosslinking agent contained in Kukaimono include silanes or siloxanes having two or more hydrolyzable groups in one molecule, and the functional groups include alkoxy groups, alkenyloxy groups, carboxyl groups, etc. , an agono group, an aminoxy group, an oxime group, an amide group, and the like.

Usually, a curing catalyst is used in the above condensation type curable organoborisiloxane composition. Examples of the curing catalyst include dibutyltin diacetate, dibutyltin dilaurate, butyltin tri-2-ethylhexoate, iron-2-ethylhexoate, cobalt-2-ethylhexoate,
Manganese-2-ethylhexoate, zinc-2-ethylhexoate, stannous caprylate, tin naphthenate, tin oleate, tin butyrate, titanium naphthenate, zinc naphthenate, cobalt naphthenate, stearic acid Metal salts of organic carboxylic acids such as zinc; organic titanate esters such as tetrabutyl titanate, tetra-2-ethylhexyl titanate, triethanolamine titanate, tetra (isoprobenyloxy) titanate: organosiloxy titanium, β-carbonyl titanium Organic titanium compounds such as; alkoxydial ξnium compounds; 3-aminopropyltriethoxysilane, N-(trimethoxysilylprobyl)
Alkoxysilanes substituted with aminoalkyl groups such as ethylene diamine; amine compounds and their salts such as hexylamine and dodecylamine phosphate; lower fatty acid salts of alkali metals such as potassium acetate, sodium acetate, and lithium oxalate; dimethylhydroxylamine , dialkylhydroxylamines such as diethylhydroxylamine, tetramethylguanidine, guanidine compounds represented by the following, and guanidyl group-containing silane and siloxane compounds.

These crosslinking agents may be used alone or as a mixture of two or more.

Diorganoborisiloxanes used as the main ingredient in platinum addition-curing organoborisiloxane compositions include those having a vinyl group at the end of the molecular chain and/or in the molecular chain; For example, a linear, cyclic, or branched organohydrogenpolysiloxane having at least two St--H groups in one molecule is used. As a catalyst for the addition reaction, metals from Group 1 of the Periodic Table of Elements can be used, but it is particularly preferable to use platinum-based compounds or complexes of platinum and olefins. As the main diorganoborisiloxane used in the organic peroxide vulcanized organoborisiloxane composition, there may be mentioned those having a vinyl group at the end of the molecular chain and/or in the molecular chain, Organic peroxides used as crosslinking agents include penzoyl peroxide,
Examples include dicumyl peroxide and di-t-butyl peroxide.

The diorganoborisiloxane as the main ingredient used in the radiation-curable organopolysiloxane composition is as follows:
Vinyl group, allyl group, at the end of the molecular chain and/or in the molecular chain,
Some of them have unsaturated groups such as alkenyloxy groups and acrylic groups, mercapto groups, eboxy groups, and hydrosilyl groups.As reaction initiators, acetophenone, probiophenone, penzophenone, xanthol, flu Olein, benzaldehyde, anthraquinone, triphenylamine, carbazole, 3-methylacetophenone, 4-methylacetophenone, 3-
Pentylacetophenone, 4-methoxyacetophenone, 3-promoacetophenone, 4-allylacetophenone, p-diacetylbenzene, 3-methoxybenzophenone, 4-methylbenzophenone, 4-chlorobenzophenone, 4. 4゜-Dimethoxybenzophenone, 4-chloro 4゛-benzylbenzophenone, 3-chloroxanthone, 3.9-dichloroxanthone, 3-chloro-8-nonylxanthone, benzoin, benzoin methyl ether, penzoin butyl ether, bis(4-
(dimethylaminophenyl)ketone, pendylmethoxyketal, 2-chlorothioxanthone, and the like.

The diorganoborisiloxane used as the main component of the grease composition is preferably one with a trimethylsilyl group at the end of the molecular chain, and metal soaps such as lithium stearate, Erosil, etc. are used as thickeners. ．． The organic compound capable of coordinating with metal used in the present invention is not particularly limited as long as it has a boiling point of 50 to 300°C at normal pressure. Preferably one that does not indicate gender. Specific examples of such organic compounds include ethers such as anisole and diglyme, β-based compounds such as ethyl acetoacetate, and methyl acetoacetate.
-ketoesters, diketones such as acetylacetone,
Phosphines such as triethylphosphine and triphenylphosphine, phosphites such as trimethylphosphite and tributylphosphite, phosphates such as trimethylphosphate, triethylphosphate, and triphenylphosphate, or organic phosphorus compounds, styrene, 1-octene, cyclohexane, etc. Examples include olefins such as / , acetylene compounds such as / , sulfides such as diphenyl sulfide and phenylbenzyl sulfide, sulfoxides such as dimethyl sulfoxide, lactones, and lactams. The amount of the organic compound capable of coordinating with metal is 0.01 to 15 parts by weight, preferably 0.1 to 15 parts by weight, per 100 parts by weight of organoborisiloxane.
It is 5 parts by weight. The amount added is o. If it is less than oi parts by weight, there is no effect, and if it exceeds 15 parts by weight, the physical properties of the silicone composition will deteriorate. tI of the present invention! If necessary, various fillers may be added to the i-kaimono. Such fillers include finely powdered silica such as fumed silica and precipitated silica, diatomaceous earth,
Metal oxides such as iron oxide, zinc oxide, titanium oxide, or their surfaces treated with silane, calcium carbonate,
Examples include metal carbonates such as magnesium carbonate and zinc carbonate, asbestos, glass wool, carbon plaque, fine mica powder, fused silica powder, and resin powders such as polystyrene, polyvinyl chloride, and polypropylene. It is preferable to remove moisture from these fillers by drying them before use. The blending amount of the filler is arbitrary as long as it does not impair the purpose of the present invention. In addition, pigments, dyes, antiaging agents, antioxidants, antistatic agents, flame retardants such as antimony oxide and chlorinated paraffin, thermal conductivity improvers such as boron nitride, etc. are added to the Kumikaimono of the present invention. If necessary, so-called carbon functional silane having amino groups, epoxy groups, thiol groups, etc. may be used as an adhesion aid, and conventionally known additives such as metal salts of carboxylic acids, metal alcoholates, etc. You can also mix them. Since the assembly of the present invention does not cause electrical contact failure,
Suitable for applications such as adhesives for electrical and electronic parts, coating agents, potting materials, rubber molded products, and damper grease.

<<Example>> Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited thereto.

Example 1. The low molecular weight siloxane content is 1. At 0%, the viscosity is 5.0
00cs, 94 parts of dimethylborisiloxane whose molecular chain ends are blocked with hydroxyl groups, 5 parts of tetraethoxysilane
0.1 part of diptyltin dimaleate and 1.0 part of ethyl acetoacetate were uniformly mixed and cured at room temperature for 24 hours. In addition, the said low molecular weight siloxane is a general formula cyclic dimethylborisiloxane, and n is 3-20.

Next, put 100g of the obtained cured product into a container with a volume of 5G,
Variable constant voltage power supply (2.oV-150mA) shown in Figure 1
)by? We conducted a mounting test of the 4-piece t7 motor (M),
The waveform of this motor was observed using a synchroscope. Assuming that a contact failure occurs when the waveform becomes abnormal, we investigated the occurrence of contact failures for these group kaimono, and the results shown in Table 1 were obtained. Table 1 Example 2. A silicone composition was prepared in exactly the same manner as in Example 1 using the same dimethylpolysiloxane as that used in Example 1, except that the low molecular weight siloxane content was 0.2%. The obtained kumikaimono was evaluated in the same manner as in Example 1, and the results are shown in Table 1. Comparative example 1. A silicone composite bottom was prepared in exactly the same manner as in Example 1, except that ethyl acetoacetate was not used. The obtained assembled bottom was evaluated in exactly the same manner as in Example 1, and the results are shown in Table 1. Example 3. ~7. Comparative example 2. It has a viscosity of 3,000 cs, a vinyl group at the end of the molecular chain, a phenyl group content of 10 mol%, and a low molecular weight siloxane content of 0. 31i% by weight of methylphenylbolysiloxane: 97 parts by weight, 3 parts of Si-H group-containing methylhydrogenbolysiloxane having a viscosity of 20 cs, and an isopropanol solution of chloroplatinic acid, based on the amount of platinum based on the total polysiloxane. 50 ppm, and as shown in Table 2, various organic compounds capable of coordinating with metals were added or not added at all, and the mixture was cured at room temperature for 24 hours. The obtained cured product was evaluated in the same manner as in Example 1, and the results shown in Table 2 were obtained. / Ten'' Examples 8. to 11. Comparative Example 3. Dimethylsiloxane units: 90 mol%, methylvinylsiloxane units: 5 mol% and methylphenyl units: 5 mol%, and the molecular chain terminals are blocked with trimethylsiloxy groups. 100 parts of a polysiloxane with a viscosity of 100,000 CS and a low molecular weight siloxane content of 1.5% and 3 parts of dicumyl peroxide were uniformly mixed to obtain a peroxide vulcanized siloxane. Next, after adding the organic compounds shown in Table 3 to the above composition or without adding them at all, the mixture was heated at 180'C for 10
The resulting cured product was evaluated in the same manner as in Example 1, and the results shown in Table 3 were obtained. / / 6'' From the results of the above examples and comparative examples, it was demonstrated that the silicone bottom of the present invention is extremely unlikely to cause contact failure.

[Brief explanation of drawings]

Figure 1 is a schematic diagram of the implementation of a micromotor using a variable constant voltage power supply. M in the figure represents a micromotor.

Claims (1)

[Claims] 1) A silicone composition comprising 100 parts by weight of an organopolysiloxane composition and 0.01 to 15 parts by weight of an organic compound capable of coordinating to metals.