JPS60101146A - Polyorganosiloxane composition having adhesiveness - Google Patents

Abstract

PURPOSE:The titled composition having excellent adhesiveness made by compounding a specified silicon resin, an epoxy compound, an organic aluminum compound, and a catalyst such as a platinum type. CONSTITUTION:100pts.wt. polyorganosiloxane (A) having 2 or more units of formula I [where R<1> is an alkenyl; R<2> is a univalent aliphatic hydrocarbon radical containing no unsaturated bond; a is 1 or 2; b is 0-2 (a+b is 1-3)], a polyorganohydrogensiloxane (B) consisting of the units shown by formula II [where R<3> is a univalent hydrocarbon radical, c is 0-2; d is 1 or 2 (c+d is 1-3)] and having 2 or more hydrogen atoms attached to a silicon atom, 0.1-20pts.wt. epoxy compound (C) (e.g. glycidoxypropyltrialkoxysilane), 0.01-10pts.wt. organic aluminum compound (D) (e.g. bis(ethyl acetoacetate)aluminum monoacetylacetonate), and a Pt (or Pb, Rh) catalyst (E) are compounded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polyorganosiloxane composition that cures by relatively gentle heating and firmly adheres to various materials upon curing.

A polyorganosiloxane composition that is cured by an addition reaction between an unsaturated group bonded to a silicon atom and a hydrogen atom bonded to a silicon atom is known as an addition reaction type silicone rubber. This addition reaction type polyorganosiloxane composition can be cured in a short time by heating,
Since no by-products are generated during curing, and the cured product has excellent flame retardancy and electrical insulation properties, it is used in a wide variety of fields.

However, such conventionally known addition reaction type polyorganosiloxane compositions have had the disadvantage of poor adhesion to materials with which the composition is in contact during curing. Therefore, when used for botting, dipping, coating, etc. of electrical and electronic parts, only inferior moisture resistance reliability can be obtained, and the range of use for these has been limited to some extent. Therefore, in order to improve the adhesion of this polyorganosiloxa 7 composition, it has been proposed to add various adhesion-imparting components. Such components include, for example, a cohydrolyzate of vinyltrialkoxysilane and vinyltrichlorosilane (
JP-B No. 47-38255), silane or siloxane and peroxide having an acryloxyalkyl group (JP-A-48-IH52), polyorkahyl i-rogensiloxane having an epoxy group and/or an ester group (Japanese Unexamined Patent Publication No. 50-39345), etc.
In both cases, the heating temperature for developing adhesive properties is relatively high. In addition, it adheres well to metals such as aluminum, stainless steel, and mild steel, but it also adheres well to plastics, especially engineering plastics that have become widely used in recent years, such as polycarbonate and polyphenylene oxide (PPO).
There was a drawback that adhesion to polybutylene terephthalate (PBT)', polyphenylene sulfide (PPS), 6-nylon, etc. was insufficient.

One of the inventors of the present invention previously proposed that at least one hydrogen atom bonded to a silicon atom is added to the molecule as an adhesion-imparting component.
Has at least one group represented by the formula % formula % (in the formula, Q and Q2 are linear or molecular fullkylene groups, and R is an alkyl group having 1 to 4 carbon atoms) in the molecule. It is proposed to add an organosilicon compound (Japanese Patent Application Laid-open No. 4885-1985).
Publication No. 4). It is also proposed to use polyorganosiloxanes having at least two silicon-bonded alkenyl groups in the molecule, which have epoxy groups, ester groups, or trialkoxysilyl groups in their side chains. (Unexamined Japanese Patent Publication No. 54-58755-5)
Publication No. 8757). Unlike the above-mentioned materials, these compositions exhibit good adhesion to metals such as aluminum, stainless steel, and mild steel even when cured at relatively low temperatures. However, PP in engineering plastics
Adhesion to O and PPS was still insufficient.

As a result of intensive studies on adhesion-imparting components, the present inventors have now provided a polyorganosiloxane composition that overcomes these drawbacks. Specifically, the present invention provides the following components (A) to (E), (wherein R is an alkenyl group, R2 is a substituted or unsubstituted monovalent hydrocarbon group that does not contain an aliphatic phase bond, and a is 1 and 2, b is a number selected from 0, 1 and 2, and a+b is a number selected from 1.2 and 3) in the molecule. Polyorganosiloxane 100 Acid part (B) General formula R6H6''' 10 (4-(c+d)
(wherein R3 is a substituted or unsubstituted monovalent hydrocarbon group, C is a number selected from 0.1 and 2, and d is 1 and 2.
and C+d is a number selected from 1.2 and 3), and has at least two hydrogen atoms bonded to silicon atoms in the molecule. , the amount of hydrogen atoms bonded to this silicon atom is 0.5 to 11 R in the polyorcasiloxane (^)
5.0 polyorkahydrodienesiloxane (C) 0.1 to 20 parts by weight of an epoxy compound (D) 0.01 to 10 parts by weight of an organoaluminum compound (E) A catalytic amount of platinum, palladium The composition contains a polyorganosiloxane composition having adhesive properties, which is made of a rhodium-based compound or a rhodium-based compound.

(A) Polyorganosiloxa 7 used in the present invention
C. One molecule has at least two alkenyl groups directly bonded to a silicon atom. This polyorganosiloxane may be linear, monobranched, resin-like, or a mixture thereof, but chain-like polyorganosiloxane is preferable because it is easy to synthesize and provides an elastic adhesive. Polyorganosiloxane is preferred. Examples of R1 in the above general formula include a vinyl group, an allyl group, and a -butenyl group, but a vinyl group is preferred from the viewpoint of economy and ease of production.

Examples of the organic group bonded to the silicon atom of R2 and other siloxane units include alkyl groups such as methyl, ethyl and propyl groups, aryl groups such as phenyl, chloromethyl, 3,3,3. - A trifluoropropyl group is preferred, and a methyl group is particularly preferred from the viewpoint of economical efficiency and ease of production, where R1 and R2 are as described above).
It may be present anywhere in the middle or both places, but in order to provide excellent mechanical properties to the composition after curing, it is preferable that it be present at least at the end of the composition. In order to use it as ink, coating, adhesive, etc., the viscosity at 25°C must be 10~10.
500000cP, especially 100-100000c
Preferably it is P.

The polyorganohydrodiene siloxane as the component (B) used in the present invention undergoes an addition reaction with the alkenyl group of the component ('A) in the presence of an addition reaction catalyst described later to cure the composition of the present invention. It is an essential ingredient for

The molecular structure of component (B) is not particularly limited as long as it has two or more 5i-H bonds in one molecule, and conventionally known linear, cyclic, or branched ones can be used. However, linear or novitrogen siloxane is preferred from the viewpoint of ease of synthesis. Examples of the organic group bonded to the silicon atom of R3 and other siloxy units include alkyl groups such as methyl group and ethyl group, and aryl groups such as phenyl group.
Alternatively, a phenyl group is preferable, and a methyl group is more preferable from the viewpoint of economical efficiency and ease of production.

The amount of component (B) to be used is 0.00% of hydrogen atom bonded to silicon atom per R1 of component (A), that is, one alkenyl group.
The amount is preferably 5 to 5.0 pieces, preferably 0.7 to 3.0 pieces. This is because if the number of hydrogen atoms is less than 0.5, no crosslinking occurs, and if the number exceeds 5.0, foaming tends to occur during curing, and changes in physical properties (especially heat resistance) after curing become large.

The epoxy compound as component (C) used in the present invention is:
This component is used together with component (D), the aluminum compound, to impart excellent self-adhesive properties to the composition of the present invention. This epoxy compound may be any compound having at least one epoxy group in one molecule. Examples of such compounds include the following. In addition, in the following formula, M
e is a methyl group, Et is an ethyl group, Pr is a propyl group, B
u represents a butyl group.

0 0 O Me Me Me OMe Me OMe (n is O or a positive integer) OMe Me OMe (n is O or a positive integer) These epoxy compounds are epoxy group-containing alkoxysilanes because they are less irritating. Among them, glycidoxyprobyltrialkoxysilane or 3,4-epoxycyclohexyltrialkoxysilane, which is highly compatible with component (A), is particularly preferred. Also preferred is an epoxy compound having an unsaturated group in the molecule, which does not reduce the physical properties of the composition after curing. The amount of these epoxy compounds used is 0.1 to 20 parts by weight, more preferably 0.1 to 20 parts by weight per 100 parts by weight of component (A).
It is 5 to 10 parts by weight. This is because sufficient adhesion force was not obtained below the Q, lfi amount and floor portion.

On the other hand, if the amount exceeds 20 parts by weight, the physical properties of the resulting cured product will deteriorate significantly.

The organic aluminum compound as component (D) used in the present invention is used together with the epoxy compound as component (C) for the purpose of imparting adhesive properties to the composition of the present invention. These include (MeO)3Al, (EtO)3Al.

Aluminum alcolade such as (n-PrO)3A1,
Aluminum salts such as naphthenic acid, stearic acid, octylic acid or benzoic acid, aluminum chelates such as those obtained by reacting aluminum alcoholade with acetoacetate or dialkyl malonate, organic acid salts of aluminum oxide, and aluminum Examples include acetylacetonate, but aluminum chelate or aluminum alcoholade is preferred from the viewpoint of hydrolyzability. Further, bisethylacetoacetate aluminum monoacetylacetonate or acetalkoxyaluminum diisopropylate is preferred because they are liquid and easy to handle. The amount of this component (D) used is:
0.01-10 parts by weight, preferably 0.1-5 parts by weight, based on component (A). If it is less than 0.01 parts by weight, good adhesion cannot be obtained, and if it exceeds 10 parts by weight, heat resistance This is because your sexuality will deteriorate. The amount of component (C) is preferably 1 to 50 parts by weight per 100 parts by weight of component (C).

Platinum-based, rhodium-based component (E) used in the present invention,
The palladium-based compound is a catalyst used as an addition reaction catalyst for the component (A) and component (B) to cure the composition of the present invention. This includes chloroplatinic acid,
Examples include alcohol-modified chloroplatinic acid, complexes of platinum and olefins, complexes of platinum and ketones, complexes of platinum and vinylsiloxane, platinum supported on a carrier such as alumina or silica, and platinum black. A platinum-based compound, a palladium-based compound exemplified by tetrakis(triphenylphosphine)palladium, a mixture of palladium black and triphenylphosphine, or a rhodium-based compound can be used. Component (E) is used in the required amount as a catalyst, and this amount is 0.0% when converted to the amount of each element of platinum, palladium, and rhodium relative to component (A).
1 to 1 (100 PP11, preferably 0.5 to 2.00 PP II.0.,
If the catalyst concentration is less than lPP11, the catalyst concentration will be low and the effect will be insufficient. On the other hand, component (E) contains precious metals and is generally expensive, so adding a large amount will be uneconomical, and 1100
Such a range is tentatively defined because there is no point in increasing the amount more than 0 pp, and the heat resistance will deteriorate further.

The composition of the present invention may contain fillers, pigments, heat resistance improvers, fungicides, etc., as necessary.
Fumes silica, precipitated silica, quartz powder, diatomaceous earth,
Examples include titanium oxide, aluminum oxide, zinc oxide, iron oxide, cerium oxide, mica, Furinin carbon black, graphite, calcium carbonate, zinc charcoal, manganese carbonate, cerium hydroxide, glass beads, and metal powder. Further, a solvent or other polyorganosiloxane may be used in combination or diluted within a range that does not impair the effects of the present invention.

Examples of the present invention are shown below. As is clear from these examples, the composition of the present invention is cured by relatively gentle heating, and is not only effective against metals, but also against ppo, PB, etc.
It also has good adhesion to engineering plastics such as T. Therefore, unlike conventional addition reaction type polyorganosiloxane compositions, it has a wide range of uses for various materials, and can be particularly preferably used as a coating agent for electrical and electronic parts. In addition, in the examples, all parts represent parts by weight.

Polyorganosiloxane, represented by CH3CH3CH3, with dimethylvinylsilyl groups blocked at both ends of the molecular chain (viscosity 500c at 25°C)
P)' 100 parts, 100 parts of quartz powder with an average particle size of 1 ol, 0.1 part of a platinum chloride octatool solution containing 2% by weight of platinum and a polyorganohydrodiene siloxane of the formula 0%. γ-glycidoxypropyltrimethoxysilane as an epoxy compound and bisethyl acetoacetate aluminum monoacetylacetonate as an aluminum compound are added to the base compound lθ0-l in the amounts (parts) shown in Table 1, respectively. It was applied onto a P2O plate, heated at 100°C for 1 hour, and its adhesion was examined. In addition,
Experiments Nb2, 3, and 4 are comparative examples.

Example 2 To the base compound described in Example 1, epoxy compounds and aluminum compounds as shown in Table 2 were added in the amounts (parts) shown in Table 2, and the mixture was sandwiched between a PBT board, an At board, and a P2O board. "C" for 1 hour, and the adhesion was examined. However, Experiments 1b6, 8, 10.11 are comparative examples. The evaluation of the adhesion results is the same as in Example 1.

Table 1 O: The rubber part was cut when it was forcibly removed.

×: It was easily removed.

Claims (1)

[Scope of Claims] 1. The following components (A) to (E), namely (wherein R is an alkenyl group and R2 is a substituted or unsubstituted monovalent hydrocarbon group that does not contain an aliphatic phase bond) , a is a number selected from 1 and 2, b is a number selected from 0. and 2,
100 parts by weight of a polyorganosiloxane having at least two units represented by the formula R6HdS+0 (4-(c+d) in the formula , R3 is a substituted or unsubstituted monovalent hydrocarbon group, C is a number selected from 0, 1 and 2, d is a number selected from 1 and 2, and C+d is selected from 1.2 and 3. The polyester of (A) has at least two hydrogen atoms bonded to silicon atoms in the molecule, and the amount of hydrogen atoms bonded to silicon atoms is 0.5 to 5.0 per R' in organosiloxane
polyorganohydrodienesiloxane (C:) 0.1 to 20 parts by weight of an epoxy compound (D) 0.01 to 10 parts by weight of an organoaluminum compound (E) A catalytic amount of platinum-based, palladium-based or A polyorganosiloxane composition containing a rhodium-based compound and having adhesive properties. 2. The composition according to claim 1, wherein R1 in 2(^) is a vinyl group. Claim 2, wherein the polyorganosiloxane of 3(A) is a polyorganosiloxane represented by the general formula 2% (wherein R2 is as described above, n represents a number from 20 to 5000) Compositions as described. The polyorganosiloxane of 4(A) has the general formula 〇H2=
C) I-3iO-(Sin)-3i-CH-CHll
5. The composition according to claim 3, which is a polyorcasiloxane represented by the formula ``l2CH3CH3CH3 (wherein n is as described above). Formula % (wherein R4 is a hydrogen atom or a methyl group, p is 0 to 10
0 (However, when R4 is a methyl group, p is 2 to +00) (
7) The composition according to any one of claims 1 to 4, which is a polyorganohydrodiene siloxane represented by the following formula (where q is a number from 0 to loo). The polyorganohydrodiene siloxane of 6(B) is
(C)13)2) A composition according to any one of claims 1 to 4, comprising 5102 units of ISiO. 7. The composition according to any one of claims 1 to 6, wherein the epoxy compound (C) is an epoxy group-containing alkoxysilane. 8(C) is an epoxy compound. 8. The composition according to claim 7, which is an epoxy compound represented by the formula (wherein R represents a substituted or unsubstituted monovalent hydrocarbon group containing no aliphatic unsaturated bond). The epoxy compound of 8(C) is. . ) -S, -CHCH-"""0 3 22° C. (wherein R is as described above). 10. The composition according to claim 7, which is an epoxy compound represented by: Claim 15, wherein the epoxy compound is an epoxy compound having an unsaturated group in its molecule.
The composition according to any one of Item 6. The composition according to any one of claims 1 to 1θ, wherein the aluminum compound of 1t (D) is an aluminum chelate or an aluminum alcoholade. 12. The composition according to claim 11, wherein the aluminum compound (D) is an aluminum chelate. 13. The composition according to claim 12, wherein the aluminum compound (D) is bisethylacetoacetate aluminum monoacetylacetonate. 13. The composition according to claim 12, wherein the aluminum compound of +4 (D) is acetalkoxyaluminum diisopropylate.