JPS5966422A - Silicone resin manufacturing method - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a silicone resin, and particularly to a method for producing a silicone resin that is soluble in organic solvents and has excellent heat resistance.

Conventionally, as a method for producing silicone resin soluble in organic solvents, two layers are formed of a ketone (A) that cannot be mixed with water in any proportion and water (B) that contains an amine, and then an alkyl A method is known (Japanese Unexamined Patent Publication No. 111198/1983) in which trichlorosilane is added and hydrolysis and condensation reactions of alkyl (IJ) dichlorolane are carried out at the interface between two layers. However, the silicone resin obtained by this reaction has a too low molecular weight, making it difficult to collect the precipitate, and although it is certainly soluble in organic solvents after the reaction is complete, it becomes insoluble in organic solvents when left at room temperature. However, it has the disadvantage of poor storage stability and is extremely difficult to handle.

On the other hand, as a method for producing high molecular weight silicone resin, methyltrialfoxy/silane with a chlorine content of 0.1 to 5.0% by weight is added to a solution containing an alkaline earth metal hydroxide or an alkali metal carbonate. , a method of carrying out a hydrolysis and condensation reaction (Japanese Patent Publication No. 56-39808), a method of co-hydrolyzing an organohalogensilane and a bifunctional siloxane,
A method is known (Japanese Patent Publication No. 34,600/1983) in which a strong alkaline substance such as a metal hydroxide is added to a solution in an inert solvent and reacted at a temperature of room temperature to 160°C.

However, in conventional methods carried out in the presence of these metal hydroxides, it is difficult to control the reaction and lacks reproducibility, and furthermore, it is inevitable that the catalyst will be mixed into the silicone resin produced. Catalytic polymerization occurs due to the catalyst, and it has disadvantages such as the inability to obtain products with excellent thermal stability.

An object of the present invention is to eliminate the drawbacks of the above-mentioned conventional methods and to produce a polymeric silicone resin from alkoxysilicates that is soluble in organic solvents and has excellent storage stability and thermal stability.

The method for producing a silicone resin of the present invention has the general formula R1Si
(ORz) m (wherein R1 means a hydrogen atom, a lower alkyl group, an alkenyl group or an aryl group, and R2 means a lower alkyl group) alone, or together with the trialkoxysilanes, general Formula R
5RaSi (ORs)z (wherein R4 and R4 are the same or different and mean a hydrogen atom, a lower alkyl group, an alkenyl group, or an aryl group, and R5 means a lower alkyl group) and an organic It is characterized by carrying out a heating reaction in the presence of a solvent, water and an organic base.

[When carrying out the method of the present invention] ~ If the general formula RrSi (
OR2) Trialkoxysilanes represented by 3, or the trialkoxysilanes and the general formula R3RtS
A dialkoxysilane represented by L(OR5)2 is heated in the presence of an organic solvent, water and an organic base to obtain υ1.
Water splitting and condensation reactions stop.

The general formula R15t (ORz
) R1 in trialkoxysilanes represented by 3
Preferred examples include a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an aryl group having 6 to 10 carbon atoms, particularly a hydrogen atom, a methyl group, an ethyl group, a vinyl group, Allyl, propenyl, phenyl or tolyl groups are preferred. Also, as R2, the number of carbon atoms is 1
-5 alkyl groups, especially methyl or ethyl groups are preferred.

Examples of these trialkoxysilanes include trimethoxysilane, triethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltripropoxysilane, ethyltriptoxysilane, propyltripropoxysilane, propyltriethoxysilane,
Butyltrimethoxysilane, butyltriethoxysilane, pentyltributoxysilane, pentyltriethoxy 7rane, vinyltrimethoxysilane, vinyltriethoxysilane, allyltripropoxysilane, allyltriptoxysilane, propenyltriethoxysilane, flobenyltripropoxy Silane, butenyltrimethoxysilane, butenyltriethoxysilane, pentenyltriptoxysilane, pentenyltripentoxysilane, phenyltrimethoxysilane, phenyltripropoxysilane, tolyltrimethoxysilane, tolyltributoxysilane, dimethylphenyltrimethoxysilane , ethylphenyltrimethoxysilane, ethylphenyltriethoxysilane, butylphenyltripropoxysilane, butylphenyltrimethoxysilane, and the like.

Further, as R3 or R4 in the dialkoxysilane represented by the general formula R3R4Si (ORB)2,
Hydrogen atom, alkyl group having 1 to 5 carbon atoms, 2 to 5 carbon atoms
5 alkenyl groups and C6-C10 alkenyl groups are preferred, and hydrogen atoms, methyl groups, ethyl groups, vinyl groups, allyl groups, flobenyl groups, phenyl groups, and tolyl groups are particularly preferred. Further, R5 is preferably an alkyl group having 1 to 5 carbon atoms, particularly a methyl group or an ethyl group. Examples of these dialkoxysilanes include methyldimethoxysilane, methyljethoxysilane, methyldibutoxysilane, ethyldipropoxysilane, ethyldibenoxysilane, propyldimethoxysilane, propyldibutoxysilane, butyljethoxysilane, and pentyldibutoxysilane. Dibutoxy 7rane, vinyldimethoxysilane, phenyldiethoxysilane, tolyldimethoxysilane, dimethyldimethoxysilane, dimethyldimethoxysilane, ethylbrobyldiethoxysilane, dipropyldimethoxysilane, methylbentyldibutoxysilane, methylvinyljethoxysilane, Ethylallyldimethoxysilane, propylbutenyldipropoxysilane, ethylphenyldimethoxysilane, butylphenyldiethoxysilane, methyltolyldipropoxysilane, ethyl(dimethylphenyl)dibutoxysilane, phenylvinyldimethoxysilane, tolylyljethoxysilane, phenyl Examples include vinyldimethoxysilane.

These trialkoxysilanes or dialkoxysilanes may be used alone or in combination of two or more. In addition, trialkoxysilane can be used alone or in combination with the above-mentioned dialkoxysilanes. When trialkoxysilanes and dialkoxysilanes are used together, the side dish of dialkoxysilanes is trialkoxysilane. The amount is less than 1 mol, particularly preferably 0.5 mol or less, per mol of silane. The higher the ratio of dialkoxysilanes to trialkoxysilanes, the lower the softening temperature of the obtained silicone resin, and the lower the temperature at which weight loss by heating begins. When using both together,
A mixture of trialkoxysilanes and dialkoxysilanes may be simultaneously hydrolyzed and condensed, or one of trialkoxysilanes or dialkoxysilanes may be hydrolyzed and condensed, and then oil is added. Further hydrolysis and condensation may be carried out, and the method and order of these additions are not particularly limited.

The organic solvent used in the present invention is not particularly limited as long as it dissolves the alkoxysilanes mentioned above and is inert to hydrolysis and condensation reactions.

Among these solvents, particularly preferred are ketones, esters, ethers, and alcohols such as methyl ethyl ketone, methyl isobutyl ketone, and diethyl ketone, esters such as n-butyl acetate, isoamyl acetate, and ethers such as tetrahydrofuran. , ethylene glycol, dichloroether, dioxane, etc. Alcohols include hexanol, 4
-Methyl-2-pentanol and the like. These organic solvents can be used alone or in combination with others. Use of organic solvent 1 is 3 to 1 total volume of trialkoxysilanes and dialkoxysilanes.
~30 parts by volume is suitable.

The organic base is usually a primary to tertiary amine, such as triethylamine, tripropylamine, tributylamine, diethylamine, ethylamine, dipropylamine,
Ethylenediamine, triethylenediamine, aniline,
Aliphatic amines or aromatic amines such as pyridine are preferably used.

A particularly preferred organic amine has an acid dissociation constant in water (
7) An organic amine with a pKα of 7 or more, particularly preferably one with a pKα of 10 or more, such as triethylamine and diethylamine.

The amount of organic amines used varies depending on the type of amine used and the reaction conditions, and is not particularly specified, but is 0.0% based on the total amount of trialkoxysilanes and dialkoxysilanes.
Generally, it is about 5 to 3 times the molar amount (9). The appropriate amount of water to be used is about 3 to 30 times the molar amount of the total amount of trialkoxysilanes and dialkoxysilanes. This also applies to the amount used in the case of organic salts other than amines.

In the method of the present invention, the hydrolysis and condensation reactions are carried out by mixing an organic solvent in which an alkoxysilane is dissolved, water and an organic base, and heating this mixture in an oil bath. The heating temperature is usually 130°C or less, but 6
It is preferable to heat at 0 to 120°C for about 1 to 6 hours. Note that during the heating operation, the mixed liquid may be stirred, or the mixed liquid may be left under rapid flow.

After the reaction is completed, the organic solvent layer is separated from the reaction solution and washed with water. Cleaning with water containing a small amount of 1, such as an aqueous ammonium nitrate solution of about 0.2% by weight, facilitates the cleaning operation. After washing until the water after washing becomes neutral,
The desired silicone resin is obtained by drying the organic solvent layer with a desiccant such as anhydrous calcium sulfate or molecular sheep, if necessary, and concentrating to dryness. In addition,
Instead of the concentration to dryness described in (10) above, the silicone resin may be separated by pouring the liquid concentrated to an appropriate concentration into a solvent that does not dissolve the silicone resin, such as acetonitrile.

The silicone resin thus obtained usually has a polystyrene equivalent molecular weight of 3000 to 200,000.
0, it has good storage stability and will not become insolubilized even if stored at room temperature for a long time, for example, 2 to 3 months.

When the silicone resin obtained by the method of the present invention uses trialkoxysilane alone as a raw material, strong absorption is observed in the infrared absorption spectrum near 11351' and 10401-1.

On the other hand, the following general formula (I) (in the formula & represents an organic group, and R represents the number of repeats) (1
1) Organopolysilsesquioxane soluble in organic solvents has a diameter around 1135 cvt-” and 1040 cm
Since it shows a strong specific two-tree absorption based on the stretching motion of the SLOSi bond near −1 (, L Pθlym.

Sci, Volume Cr, 83N (1963); Japanese Patent Application Publication No. 1973
-139900, etc.), and the silicone resin of the present invention is also considered to have the structure of the general formula (I).

On the other hand, when a mixture of trialkoxysilanes and dialkoxysilanes is used as a raw material, a silicone resin with a mixed structure of silsesquioxane units (Rx5tOb5) and tosiorganosiloxane units (YtsR4SiO) is obtained. Conceivable.

Furthermore, even when one of trialkoxysilanes or dialkoxysilanes is subjected to hydrolysis and condensation reaction, the other is further added, and the hydrolysis and condensation reaction is carried out again, the silsesquioxane unit (R+SiO
x, s) and diorganosiloxane position (R5R45i
It is thought that the structure is a mixture of O) and blue silicone resin.

The silicone resin obtained by the method of the present invention is (12) soluble in organic solvents, does not become insolubilized in organic solvents even if left in a solid state at room temperature for a long period of time, and has good storage stability. It's good. Furthermore, this silicone resin has excellent heat resistance and excellent adhesion to substrates, so it can be used in a wide range of applications, for example, as a heat-resistant insulating film.

Specific applications include, for example, insulating protective films or interlayer insulating films for integrated circuits, liquid crystal alignment auxiliary films, heat-resistant paints, and modifiers for organic polymer surfaces. In addition, the method of the present invention does not use halogen compounds or metal hydroxides in the process, so the produced silicone resin is not contaminated with halogens or metals, and is especially suitable for integrated circuits that require high purity. It is suitable as a material in the electrical and electronic fields, such as an insulating protective film or an interlayer insulating film, a sealing or insulating material for semiconductor elements, and a material for magnetic memory.

Examples of the method of the present invention are shown below, and the average molecular weights in the examples are standard polystyrene equivalents determined by the following gel permeation chromatography (hereinafter referred to as GPC) (13). It is the number average number of molecules.

GPC measurement method Equipment: High-temperature high-speed gel permeation chromatogram (Model 150-CALC/GPC manufactured by Waters, USA)
) Column: 5HODEX A-8M manufactured by Showa Denko ■.

Length 50 CrrL Measured temperature change 40'C Flow rate: lcc/min Sample: 1 g of silicone resin was dissolved in 100 ml of tetrahydrofuran. As the standard polystyrene, one piece of standard polystyrene manufactured by Pressure Chemical Company, USA was used.

Example 1 A reaction vessel equipped with a DC cooling chamber, a stirring bowl, and a dropping funnel was
495 ml (3.95 mol) of methyl isobutyl ketone, 49.5 d (0.35 mol) of methyltrimethoxysilane and 12 ml (0.086 mol) of triethylamine were added. 66 m/' (3.67 mol) of water was added dropwise to this solution from the dropping funnel (14) while stirring.
Almost no fever was observed. Next, the reaction solution was heated at an oil bath temperature of 80°C for 4 hours to cause condensation, and after the reaction was completed, the organic solvent layer was separated and treated with a 0.2 diammonium dinitrate aqueous solution.
Wash 1 until the washing aqueous solution becomes neutral. Furthermore, after drying the organic solvent 1- with molecular sieves, a solid content was obtained by distilling off low-boiling substances under reduced pressure. When this solid content was air-dried overnight at 40°C using JX, silicone resin 1
4.3g was obtained. The average molecular weight of this resin is 25.0
It was 00.

Example 2 198 ml (1.5 mol) of n-butyl acetate, 49.5 ml (0.35 mol) of methyltrimethoxysilane,
Triethylamine 12d (0,086 mol) and water 6
6m/(3.67 mol), and other operations and post-treatments were performed in the same manner as in Example 1 (-, silicone resin 14.1#).
I got it. The average molecular weight of this product was 30,000.

Example 3 (15) 4-methyl-2-pentanol 198 ml (1,,
56 mol), methyltrimethoxysilane 49.5 il (
0835 mol), triethylamine 12 m/! (0,0
86 mol) and 66 ml (3.67 mol) of water, the same operation and post-treatment as in Example 1 were carried out to obtain silicone resin 13.8.9. The average molecule of this -
It is 18,000fL*.

Example 4 7247.5 ml (3,06 mol) of tetrahydro7, 49.5 ml (0,
The pond was operated and post-treated in the same manner as in Example 1 using 12 ml (0,086 mol) of triethylamine (0,086 mol) and 66 ml (3,67 mol) of water to obtain 14.8 g of silicone resin. The average molecular weight of this substance is 23°00
It was 0.

Example 5 432 ml (3,4,5 mol) of methyl isobutyl ketone, 36 ml (0,25 mol) of methyltrimethoxy7
mol) and diethylamine 3.3 ml (0,03
Add 48 ml (2.67 mol) of water to a solution of
After 711 hours, (16) heated the mouth at 80℃ for 3 hours. Subsequent post-treatment in the same manner as in Example 1 yielded a silicone resin of 1.0.1 #, which had an average molecular weight 1 of 35,000.

Example 6 Methyltrimethoxysilane 42 m/(0.3 mol), dimethyldimethoxy7rane 6.9 mA' (0.05 mol)
and 12 m/(0,086 mol) of triethylamine were dissolved in 450 m/(3,59 mol) of methyl isobutyl ketone, 66 ml (3,67 mol) of water was added to this solution, and the mixture was heated at 90'C for 5 hours. Condensed.

The organic solvent layer was then separated and washed with an aqueous 0.2 diammonium nitrate solution until the washing water became neutral. After further concentrating the organic solution, the concentrated liquid was poured into acetonitrile, and the silicone resin was solidified and separated. This was vacuum dried overnight to obtain silicone resin 13.1.9. The average molecule l of this is 2o, o6o, and fc.

Example 7 42 ml (0.3 mol) of methyltrimethoxysilane and 10 mA of triethylamine! (0,072 mol) (1
7) was dissolved in 380 d (3.04 mol) of methyl isobutyl ketone, and 57 aJ (3.17 mol) of water was completely added to this solution, followed by heating at 80° C. for 2 hours. After cooling the reaction solution, dimethyl/methoxysilane 6.9++ was added to it.
+7! (0.05 mol) was added and further heated at 80° C. for 2 hours. Subsequently, post-treatment was performed in the same manner as in Example 6 to obtain 13 g of silicone resin.

The average molecular weight of this product was 24,000.

Example 8 11.5 m, l of triethylamine (0,088 mol), 40 m, l of methyltrimethoxysilane (0,279 mol), 5.3 m, l of vinyltrimethoxysilane! (0,
035 mo), phenyltrimethoxysilane 6.5 ru
ll (0,035 mol), methyl isobutyl ketone 36
3d (2°9 mol) and 67.5 ml of water (3,7
5 mol), and the other operations and post-treatments were the same as in Example 1, to obtain 17 g of silicone resin. The early proboscis molecular eyelid of this one was 22,000.

Example 9 Bird, T-chi #7 min 10.3 m1 (0,079 mo #
)・, (18) Methyltrimethoxysilane 40m/(0,279 mol)
and vinyltrimethoxysilane 4.8ml (0,0
31 mol) and 356 ml of methyl isobutyl ketone (
2°84 mol) and add 60 ml of water to this solution (
After adding 3.33 mol) to the mixture, it was heated at 80°C for 2 hours. Subsequently, the product was post-treated in the same manner as in Example 1 to obtain 15 g of silicone resin. The average molecular weight of this substance is 2
It was 4,000.

Example 10 Methyltrimethoxysilane 16mA! (0,112 mol), phenyltrimethoxysilane 2.3 ml (0,
O12 mol), triethylamine y4.1 m1 (0,03
1 mol) and methyl isobutyl ketone 128 m/(1
, 02 mol), otherwise the same operation as in Example 1,
6 g of silicone resin was obtained without post-treatment. The average molecular weight of this product was 30,000.

Example 11 Methyl isobutyl ketone 490 m/(3,90 mol),
Triethylamine 713.7 ml (0,098 mol)
22.6 ml (0.18 mol) of methyl isobutyl ketone, 24.6 d (0.17 mol) of methyltrimethoxysilane and 2.0 ml of trimethoxysilane were added to a mixed solution of Oyo(19) and 36++J (2.0 mol) of water. .81nl (0.02mol)
After dropping the mixed solution over about 10 minutes, the reaction solution was
Heat condensation was carried out at ℃ for 3 hours. Subsequently, it was post-treated in the same manner as in Example 1 to obtain 11.0 g of silicone resin. The average molecular weight of this resin was 17,000.

Example 12 Methyl isobutyl ketone 495 mj (3.95 mol),
Butyltrimethoxysilane 67.0d (0.35 mol
12 triethylamine (0,086 mol), 66 water
ml (3.67 moles) and the same procedure as in Example 1 was performed to obtain 13.0 # of silicone resin.

The average molecular weight of this product was 23,000.

Example 1+IJ 13 Methyl isobutyl ketone 495+++/(3,95 mol), ethyltrimethoxysilane 55 Tnl (0,35 mol), triethylamine 12+++4! (0,086 mol) and 66 ml (3,67 mol) of water, and the same operation as in Example 1 (20) was carried out to obtain 13.0 g of silicone resin.

The average molecular weight of this resin was 21,000.

Examples The thermal decomposition temperatures under nitrogen of the silicone resins obtained in Examples 1 to 13 were as shown in Table 1.

From the results shown in Table 1, it can be seen that the silicone resins obtained according to the present invention, especially the resins obtained by thermosetting the silicone resins made from trialkoxysilanes alone, exhibit extremely high (21) heat resistance.

L1 According to the present invention, a thermosetting resin that does not become insolubilized in an organic solvent even when stored at room temperature for a long period of time is obtained,
By thermoforming this, a silicone resin product with excellent heat resistance can be obtained. Furthermore, since the method of the present invention does not use metal hydroxides at all, the obtained silicone resin has excellent thermal stability during high-temperature heating, and since the metal content is extremely low, it also has excellent electrical properties such as insulation resistance. There is.

Agent: Patent Attorney Takecho Kawakita (22)

Claims (1)

[Claims] (1) Trialkoxysilanes represented by the general formula R55L(ORz) s (wherein R1 means a hydrogen atom, a lower alkyl group, an alkenyl group, or an aryl group, and R2 means a lower alkyl group), or the trialkoxy Silanes and the general formula R3R4S i (ORs) 2
(In the formula, R3 and R4 are the same or different, a hydrogen atom,
Lower alkyl group, alkenyl group or aryl group, R6
1 represents a lower alkyl group) and a dialkoxysilane represented by the formula (1) means a lower alkyl group, in the presence of an organic solvent, water and an organic base.