JPH037766A - Organopolysiloxane composition - Google Patents

Abstract

PURPOSE:To obtain a composition, containing a reaction product of a partial condensate of methylsilane and/or partial cocondensate of the methylsilane with an organoalkoxysilane with an alkoxysilane, excellent in hardness, heat resistance, etc., and preservation stability and suitable as coating materials, etc. CONSTITUTION:A composition obtained by blending a reaction product of (A) 100 pts.wt. partial condensate of methylsilane expressed by formula I [X is halogen or OR<1> (R<1> is 1-5C alkyl, etc.)] and/or a partial cocondensate of the aforementioned methylsilane with one or more organoalkoxysilanes expressed by formula II (R<2> is 1-8C organic group; a is 0 or 2) and formula III (R<3> is 2-8C organic group) with (B) 1-25 pts.wt., preferably 2-15 pts.wt. alkoxysilane expressed by formula IV (R<4> is 3-10C organic group; b is 0 or 1) in other components. The above-mentioned reaction product is blended in an amount of 10-100wt.%, preferably 20-100wt.% based on the composition.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an organopolysiloxane composition with excellent storage stability.

[Conventional technology]

Organopolysiloxane is heat resistant, weather resistant, water resistant,
It has excellent corrosion resistance, and in recent years has been widely used as a material to coat the surfaces of aluminum, ceramics, paper, glass, plastics, etc. to improve heat resistance, weather resistance, water resistance, corrosion resistance, etc. .

As such an organopolysiloxane, a methylpolysiloxane obtained by hydrolysis and partial polycondensation of methylalkoxysilane has been proposed.

However, organopolysiloxane obtained by hydrolyzing and partially polycondensing methyltrialkoxysilane undergoes a condensation reaction during storage, resulting in an increase in molecular weight, thickening, gelation, etc. It is less stable.

[Problem to be solved by the invention]

The present invention was made against the background of the above-mentioned conventional technical problems, and improves the hardness, heat resistance, weather resistance, water resistance, corrosion resistance,
An object of the present invention is to provide an organopolysiloxane composition that has excellent adhesion, bending workability, etc., good storage stability, and excellent curability during coating film formation.

[Means to solve the problem]

The present invention provides (A) general formula CR3S iX3 (wherein,
X is a halogen atom or an alkoxy group represented by OR', where R1 represents an alkyl group having 1 to 5 carbon atoms or an acyl group having 1 to 4 carbon atoms (hereinafter referred to as [(a) (hereinafter referred to as "methylsilane condensate") and/or a partial condensate of the methylsilane and the general formula R2*S t (OR
' ) a-m (in the formula, R2 is an organic group having 1 to 8 carbon atoms, a represents 0 or 2, and OR' is the same as above) and R' St (OR' )3 (in the formula, R3 is At least one organoalkoxysilane (hereinafter referred to as r (a
) (referred to as 'organoalkoxysilane') (hereinafter referred to as 'methylsilane cocondensate', the aforementioned methylsilane condensate and methylsilane cocondensate are collectively referred to as 'component (A)'); B) General formula R' (C
H3) b S i (OR') 5-b (in the formula,
R4 is an organic group having 3 to 10 carbon atoms, b is 0 or 1, R1
is the same as above) (hereinafter referred to as "("))
The object of the present invention is to provide an organopolysiloxane composition containing a reaction product (hereinafter simply referred to as "specific reaction product") with component B).

Next, the composition of the present invention will be explained in detail by component.

Among component (A), the methylsilane condensate used in the present invention is:
It is obtained by subjecting (a) methylsilane represented by the above general formula to hydrolysis and partial polycondensation.

In this (a) methylsilane, X is a halogen atom such as a chlorine atom, a fluorine atom, a bromine atom, or a group represented by OR'.

Here, R1 is an alkyl group having 1 to 5 carbon atoms or an acyl group having 1 to 4 carbon atoms, such as a methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, S -butyl group, t-butyl group, acetyl group, etc.

Specific examples of these (a) methylsilanes include methyltrichlorosilane, methyltrimethoxysilane, methyltriethoxysilane, methyltri-n-propoxysilane,
Examples include methyltrimypropoxysilane, methyltri-n-butoxysilane, methyltri-S-butoxysilane, methyltri-t-butoxysilane, and methyltriacetoxysilane.

As the component (A), the above-mentioned (a) methylsilane, the above-mentioned general formula R" a S i (OR' )a-* and R3
It may be a co-condensate obtained by co-condensing at least one (a)' organoalkoxysilane represented by S i (OR' )3.

The general formula R" a S I (OR') 4-a
In, R2 is an organic group having 1 to 8 carbon atoms, such as an alkyl group such as a methyl group, an ethyl group, an n-propyl group, or an i-propyl group, as well as a γ-chloropropyl group,
Vinyl L 3.3.3-) Lifluoroprovir group, T-glycidoxypropyl group, γ-methacryloxypropyl group, γ-mercaptopropyl group, phenyl group, 3.4-
Examples include epoxycyclohexylethyl group.

In the general formula R2@Si(OR')4-a, when a is O, the organoalkoxysilane (a)' is a tetraalkoxysilane represented by the general formula Si(OR')4. Since all four bonding points of silicon atoms are provided for siloxane bonding, it can act as a densifying component in component (A).

Specific examples of this tetraalkoxysilane include tetramethoxysilane, tetraethoxysilane, tetra n-propoxysilane, tetramypropoxysilane, tetra n-butoxysilane, tetra i-butoxysilane, tetra t-butoxysilane, and tetraacetoxysilane. Among them, tetramethoxysilane, tetraethoxysilane, and tetramypropoxysilane are preferred.

In the general formula R" @ S i (OR' ) a-*, when a is 2, such (a)' organoalkoxysilane has the general formula Rt□St (OR' )z
It is a diorganodialkoxysilane represented by the following formula, and because it can form two siloxane bonds for every one silicon atom, it is a highly flexible component that has linear siloxane bonds in the methylsilane cocondensate. can be contained.

Specific examples of such diorganodialkoxysilanes include dimethyldimethoxysilane, dimethyljethoxysilane, dimethyldipropoxysilane, diethyldimethoxysilane, diethyljethoxysilane, diethyldipropoxysilane,
-propoxysilane, di-n-propyldimethoxysilane, di-n-propyljethoxysilane, dimethyldiacetoxysilane, di-n-propyldiacetoxysilane, and the like.

Furthermore, organotrialkoxysilane represented by the general formula R35t (OR'), when a methylsilane cocondensate obtained by R3 shown in the formula is used as a coating material, improves the hardness, adhesion, and repellency of the coating film. The performance of water-based coatings can be improved.

R3 in the organotrialkoxysilane represented by the general formula R''Si (OR') is an organic group having 2 to 8 carbon atoms, such as ethyl group, n-propyl group, j-
Alkyl groups such as propyl group, as well as T-chloropropyl group, vinyl group, 3,3゜3-trifluoropropyl group, T-glycidoxypropyl group, γ-methacryloxypropyl group, T-mercaptopropyl group, phenyl group,
Examples include 3,4-epoxycyclohexyl group.

Specific examples of this organotrialkoxysilane include:
Ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, i-propyltrimethoxysilane, i
-Propyltriethoxysilane, γ-chloropropyltrimethoxysilane, T-chloropropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 3,3.3-)lifluoropropyltrimethoxysilane, 3,3. 3-) Lifluoroprobyltriethoxysilane, γ-glycidoxyprobyltrimethoxysilane, T-glycidoxyprobyltriethoxysilane, γ-
methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, T-mercaptopropyltrimethoxysilane, T-mercaptopropyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, T-aminopropyltrimethoxysilane, Examples include 3.4-epoxycyclohexylethylmethoxysilane, 3.4-epoxycyclohexylethyltriethoxysilane, and the like.
Preferably ethyltrimethoxysilane, ethyltriethoxysilane, n-7"lopyltrimethoxysilane, n-
They are propyltriethoxysilane, 1-propyltrimethoxysilane, i-propyltriethoxysilane, r-chloropropyltrimethoxysilane, and T-chloropropyltriethoxysilane.

The above co-condensation ratio of (a) methylsilane and (a)' organoalkoxysilane is (a) methylsilane 100%
Based on parts by weight, (a) 'Organoalkuki 995 F85
~0 parts by weight, preferably 70-0 parts by weight, (a)
When the resulting composition is used as a coating material when too little methylsilane is present, the curability of the material is reduced.

The weight average molecular weight of the above component (A) in terms of polystyrene is usually 500 to 300,000, preferably 800.
~100,000, more preferably 1,000-50
,000, and if it is less than 500 or more than 300,000, when the resulting composition is used as a coating material, the adhesion of the coating film tends to decrease.

Component (B) Component (B) can be added to component (A) by adding it to component (A).
) reacts with the silanol groups remaining in the component and condenses to reduce the amount of remaining silanol groups, and R4
The effect of the organic group shown in the above gives the effect of improving the storage stability of the resulting composition.

The general formula R' (CH3) b S i (OR'
) In s-b, R4 is an organic group having 3 to 10 carbon atoms, such as an alkyl group such as n-propyl group, i-propyl group, butyl group, T-chloropropyl group, 3.3. Examples include 3-trifluoropropyl group, T-glycidoxypropyl group, T-methacryloxypropyl group, T-mercaptopropyl group, phenyl group, and 3,4-epoxycyclohexylethyl group.

When the number of carbon atoms in R4 is less than 3, the effect of improving the storage stability of the resulting composition is small, while when the number of carbon atoms exceeds 10, the condensation reactivity of component (B) is significantly reduced,
Moreover, the compatibility with component (A) also decreases.

In addition, when the value of b in component (B) is 2 or more, (A
The condensation reaction with component ) consumes all the silanol groups and alkoxy groups in the reaction system, and the curability of the resulting composition is significantly reduced.

Specific examples of these component (B) include n-propyltrimethoxysilane, n-propyltriethoxysilane,
i-propyltrimethoxysilane, i-propyltriethoxysilane, T-chloropropyltrimethoxysilane, γ-chloropropyltriethoxysilane, 3,3.3
- trifluoropropyltrimethoxysilane, 3.3.3
-) Lifluoropropyltriethoxysilane, T-glycidoxypropyltrimethoxysilane, T-glycidoxypropyltriethoxysilane, T-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γmercaptopropyl Trimethoxysilane, γ-mercaptopropyltriethoxysilane, 3,4-epoxycyclohexylethyltrimethoxysilane, 3,4-epoxycyclohexylethyltriethoxysilane, T-chloropropylmethyldimethoxysilane, T-chloropropylmethyldieth 1 2 xysilane, T-glycidoxypropylmethyldimethoxysilane, T-glycidoxymethyljethoxysilane,
T-methacryloxypropylmethyldimethoxysilane, T-methacryloxymethyljethoxysilane, 3,
Examples include 4-epoxycyclohexylethylmethyljethoxysilane, preferably n-propyltrimethoxysilane, n-propyltriethoxysilane, i-propyltrimethoxysilane, i-propyltriethoxysilane, T-chloro Propyltrimethoxysilane, T-chloropropyltriethoxysilane, γ-
Glycidoxypropyltrimethoxysilane, T-glycidoxypropyltriethoxysilane, γ-mercaptopropyltriethoxysilane, T-mercaptopropyltriethoxysilane, 3.4-epoxycyclohexylethyltrimethoxysilane, 34-epoxycyclohexylethyl Triethoxysilane, etc., more preferably γ-glycidoxyprobyltrimethoxysilane, T
-glycidoxy-propyltriethoxysilane, 3.4
- epoxycyclohexylethyltrimethoxysilane,
3.4-epoxycyclohexylethyltriethoxysilane and the like.

In the present invention, the specific reaction product is component (A) 100%
Component (B) is usually added in 1 to 25 parts by weight, preferably 2 to 15 parts by weight, preferably at 50°
C or higher, preferably 60 to 80°C.

The proportion of the specific reaction product in the composition of the present invention is usually 10 to 100% by weight, preferably 20 to 100% by weight.
It is.

(C) Metal oxide sol The composition of the present invention may contain (C) metal oxide sol as necessary.

Metal oxide sols are used for the purposes of increasing viscosity, improving the heat resistance, hardness and adhesion of the resulting coating film, and preventing static electricity.

Examples of such component (C) include silica sol, alumina sol, alumina sol, and zirconia sol.

Among these, silica sol (colloidal silica) is an aqueous dispersion of highly pure silicic acid anhydride, and usually has an average particle diameter of 5 to 30 μm and a solid content concentration of about 18 to 30% by weight. This silica sol usually has a sodium content of 0.
0.005% by weight or less and is in the acidic region, that is, the pH range is from 2 to 6.

Specific examples of such silica sol include Snowtex O manufactured by Nissan Chemical Industries, Cataloid SN manufactured by Catalysts and Chemicals, Ludox manufactured by DuPont, 5yton manufactured by Monsanto, and Nalcog manufactured by Nalco Chemical. I can do it.

Furthermore, as alumina sol, aluminum oxide CA
11t Cps), nitric acid, hydrochloric acid, acetic acid, etc. are used as a stabilizer, and the particle size is 10 to 1.
00 mμ can be exemplified. This alumina sol has a pH in the acidic range, preferably in the range of 2 to 6. Specific examples of such alumina sol include Alumina Sol 100 and Alumina Sol 200 manufactured by Nissan Chemical Industries.
1 alumina sol 520 and the like.

Further, as the titania sol, a dispersion of an alkyl titanate hydrolyzate can be mentioned.

Further, the zirconia sol is an aqueous zirconium dioxide dispersion or an aqueous zirconium acetate solution, and examples of such zircoacyl include, for example, Nissan Chemical Industries.
Examples include zirconia sol NZS-20A, zirconia sol acetate, and the like.

The ratio of the above component (C) in the composition is 0 to 70
Weight%.

It is also possible to add fillers to the composition of the present invention, if necessary.

As fillers, mention may be made, for example, of organic or inorganic pigments. Examples of organic pigments include Fast Yellow G1 diazo yellow, diazo orange, naphthol red, and fluorocyanine green. Examples of inorganic pigments include particulate or fibrous metals and alloys, as well as their oxides, hydroxides, carbides, nitrides, and sulfides. Iron, copper, aluminum, nickel, chromium, lead, silver, zinc, ferrite, carbon black, stainless steel, silicon dioxide, titanium oxide, aluminum oxide, nickel oxide, copper oxide, zinc oxide, lead oxide, chromium oxide, manganese oxide , iron oxide, zirconium oxide, cobalt oxide, synthetic mullite, kaolin, mica, zircon (zirconium silicate), aluminum hydroxide, iron hydroxide, silicon carbide,
Examples include, but are not limited to, silicon nitride, boron nitride, potassium titanate, molybdenum disulfide, and the like.

The average particle size or average length of these fillers is usually 0
．． 05 to 100 μm, preferably 0.05 to 100 μm, preferably 0. If it is less than 0.05 μm, the viscosity of the composition will increase, while if it exceeds 100 μm, the dispersibility of the resulting composition may deteriorate.

The proportion of filler in the composition is usually 0 to 70% by weight.

The filler selection depends on the purpose of the coating film to be obtained.
For example, this is done based on the following selections.

■Silicon dioxide,
Use materials with excellent corrosion resistance such as titanium oxide, aluminum oxide, chromium oxide, zirconium oxide, synthetic mullite, zircon, silicon carbide, and silicon nitride.

■As a filler for making an electrically insulating film, use electrically insulating metal oxides, carbides, or nitrides that do not contain alkali metals.

■Fillers for making a cosmetic film include iron oxide, titanium dioxide, cobalt oxide, zinc oxide, tin oxide, lead oxide,
Oxides such as aluminum oxide and stainless steel are used.

■Oxides such as iron oxide, copper oxide, cobalt oxide, manganese oxide, chromium oxide, silicon dioxide, titanium oxide, aluminum oxide, and zircon are used as fillers for making the heat radiation film.

■ Copper, aluminum, nickel, silver, carbon black, tin oxide, etc. are used as fillers for making conductive or semiconductive films.

■Metal oxides, hydroxides, nitrides, etc. with low thermal conductivity are used as fillers to create the heat insulating film.

■Zinc, lead, chromium, etc. are used as fillers to create a corrosion-resistant film.

■Stainless steel is used as a filler to create a weldable membrane.

■Nickel, aluminum, mica, stainless steel, etc. are used as fillers to create a film with metallic luster.

[Phase] In addition, in order to create a coating film that takes advantage of the characteristics of various fillers, two or more of the above-mentioned fillers can be used in combination.

Next, when using the composition of the present invention as a coating material, etc., for the purpose of improving workability during coating film formation or mixing the composition of the present invention with other paint pigments or fillers,
Organic solvents can be used.

Examples of the organic solvent include methanol, ethanol, n-propyl alcohol, i-propyl alcohol,
S-butyl alcohol, t-butyl alcohol, n-pentyl alcohol, ne〇-pentyl alcohol, n-
Hexyl alcohol, n-heptyl alcohol, methyl cellosolve, ethyl cellosolve, propyl cellosolve,
Ethylene glycol, propylene glycol, methyl diglyme, ethyl diglyme, tetrahydrofuran, 1
．． 4-dioxane, acetone, methyl ethyl ketone, methyl propyl ketone, methyl n-butyl ketone, methyl isobutyl ketone, acetophenone, benzophenone,
Examples include benzene, toluene, xylene, ethyl acetate, propyl acetate, butyl acetate, dichloromethane, chloroform, carbon tetrachloride, and various fluorocarbon solvents.

The amount of this organic solvent to be added may be determined as necessary, and it may be a mixed solvent system of two or more types or more.

Furthermore, the composition of the present invention is characterized by the use of the organic solvent described above. 0 In addition, water can be mixed.

Furthermore, in order to cure the composition of the present invention more quickly, a curing accelerator may be used, and in order to cure the composition at a relatively low temperature, it is more effective to use a curing accelerator.

Such curing accelerators include alkaline compounds such as sodium hydroxide and potassium hydroxide; acidic compounds such as alkyl titanic acid, phosphoric acid, p-)luenesulfonic acid, and phthalic acid; aliphatic diamines such as ethylenediamine and hexanediamine; Aliphatic polyamines such as diethylenetriamine, triethylenetetramine, and tetraethylenepencumine; alicyclic amines such as piperidine and piperazine;
Aromatic amines such as metaphenylenediamine; ethanolamines, triethylamine, various modified amines used as curing agents for epoxy resins; γ-aminopropyltriethoxysilane, T(2-aminoethyl)-aminopropyltrimethoxysilane, Amine-based silane coupling agents such as γ-(2-aminoethyl)-aminopropylmethyldimethoxysilane and T-anilinopropyltrimethoxysilane, organic tin compounds, and the like are used.

The proportion of these curing accelerators in the composition of the present invention is usually 0.1 to 15% by weight, preferably 0.5 to 10% by weight.

In addition, various surfactants, dyes, etc. can also be added to the composition of the present invention.

The total solids concentration of the composition of the present invention is usually 5 to 80% by weight, preferably 10 to 50% by weight, particularly preferably 15% by weight.
~35% by weight, and if it is less than 5% by weight, the solid content concentration is too low and the properties such as heat resistance, water resistance, chemical resistance, weather resistance, etc. of the coating film formed by coating the resulting composition are impaired. Properties may not be expressed, and pinholes may occur in the formed coating film.On the other hand, if it exceeds 80% by weight, the solid content concentration is too high and the storage stability of the composition may deteriorate or the composition may deteriorate. Even when objects are coated, problems may occur, such as difficulty in forming a uniform coating film.

〔Example〕

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples.

In the examples, parts and percentages are based on weight unless otherwise specified. Moreover, various measurements in the examples are as follows.

The weight average molecular weight in terms of polystyrene was measured by gel permeation chromatography (CPC) under the following conditions using tetrahydrofuran as a solvent, and a sample was obtained by dissolving 1 g of organopolysiloxane in 100 cc of tetrahydrofuran. In addition, standard polystyrene manufactured by Tosoh ■ was used.

Apparatus: High performance liquid chromatogram (model LC-RID-6A) manufactured by Takashi Seisakusho Column: SHODEX A-8M manufactured by Showa Denko ■, length 50 cm Measurement temperature: 40°C Flow rate: ice/min Adhesion: After the base grain test according to JIS K5400, a tape peel test was performed three times and the average was taken.

The hardness was determined by pencil hardness according to JIS K5400.

Storage stability is determined by storing in a polyethylene bottle with a tightly stopper.
After being stored for a certain period of time in a 5°C constant temperature bath, the presence or absence of gelation was visually determined.

Examples 1 to 8 and Comparative Examples 1 to 6 In a reactor equipped with a reflux condenser and a stirrer, 100 parts of methyltrimethoxysilane and alumina sole (Nissan Chemical Industry Co., Ltd.
Add 50 parts of an aqueous dispersion (solid content 20%) and 15 parts of i-propyl alcohol, heat to 60°C and react for 4 hours, and then add 5 parts of T-glycidoxypropyltrimethoxysilane. In addition, the composition is heated to 60°C and reacted for 20 minutes, cooled to room temperature, and further added with 100 parts of i-propyl alcohol, and contains a specific reaction product having a weight average molecular weight in terms of polystyrene of s, ooo. I got it.

3 4 In the same manner as above, add component (A) and component (B) to the first
By changing as shown in the table, the composition of the present invention is
As well as the composition υ~ force for comparison was obtained.

Further, zirconium silicate and titanium dioxide were added to compositions A and II, respectively, to obtain compositions I and II.

Next, each of the obtained compositions was prepared using degreased aluminum plates (JIS K4000, A202
4) Spray-coated on top and heated at 150°C for 30 minutes to form a cured coating.

Adhesion and hardness of these cured coatings were measured. In addition, the storage stability of each composition was evaluated. The results are shown in Table 1.

(Left below) Comparative Examples 7-8 In a reactor equipped with a reflux condenser and a stirrer, methyltrimethoxysilane, T-glycidoxypropyltrimethoxysilane, and silica sol (Nissan Chemical Co., Ltd.) were added as shown in Table 2.
ethanol dispersion, solid content concentration 20%), i-propyl alcohol and water were added, heated to 60°C and heated to
After a period of reaction, compositions 1 and 2 were obtained.

As in Examples 1 to 8 and Comparative Examples 1 to 6, the obtained compositions had a polystyrene equivalent weight average molecular weight by GPC method,
Adhesion, hardness and storage stability were evaluated. The results are shown in Table 2.

(Margins below) Table 2 [Effects of the Invention] The coating film obtained by applying the composition of the present invention to coating materials has excellent curability, Various plated steel plates such as composite plated steel plates, 7 8 chemical conversion treated steel plates, stainless steel, aluminum, ceramics, cement, fibers, paper, glass, plastics (excluding those without functional groups such as fluorine resins and polyethylene) It can be used for 80
The composition of the present invention can be cured by heating for 10 to 120 minutes at ~a o o "c, and depending on the application, can be cured by drying at room temperature for 1 to 7 days. Furthermore, the composition of the present invention is a hydrolyzable composition containing water. Despite this, storage stability for 6 months or more can be ensured.

Furthermore, the coating film obtained from the composition of the present invention has excellent hardness, heat resistance, weather resistance, water resistance, corrosion resistance, adhesion, and the like.

Claims (1)

[Claims] (1) (A) General formula CH_3SiX_3 (wherein, X is a halogen atom or a group represented by OR^1, where R^1 is an alkyl group having 1 to 5 carbon atoms or
(indicating an acyl group) and/or a partial condensate of methylsilane represented by the acyl group of
_aSi(OR^1)_4_-_a (in the formula, R^2 is an organic group having 1 to 8 carbon atoms, a represents 0 or 2, R^1 is the same as above) and R^3Si(OR^1 )_3 (In the formula, R^3 is carbon number 2
~8 organic group, R^1 is the same as above) with at least one organoalkoxysilane, and (B) general formula R^4(CH_3)_bSi(OR^1 )
Contains a reaction product with an alkoxysilane represented by _3_-_b (wherein R^4 is an organic group having 3 to 10 carbon atoms, b is 0 or 1, and R^1 is the same as above) Organopolysiloxane composition.