TWI404764B - Room temperature hardening polyorganosiloxane composition - Google Patents

Abstract

A room temperature solidification organic siloxane siloxane polymer composition contains (A) 5-95% by weight of an organic siloxane siloxane polymer with both ends capped with trialkoxyl methyl silicane groups; (B) 95-5% by weight of an organic siloxane siloxane polymer with both ends capped with dialkoxyl monomethyl silicane groups, wherein there are 100 parts by weight of the organic siloxane siloxane polymer of (A) and (B); (C) 1-50 parts by weight of mono- terminal trialkoxyl organic siloxane siloxane polymer solidifying agent of the general formula (1), wherein R<1>, R<2> and R<3> are monovalent saturated alkyl, X represents oxygen atom or bivalent alkyl, n is a positive number for making the viscosity being 0.005-100 Pa.s; (D) 1-50 parts by weight of silicon dixcide powder with a specific surface area of 50m<2>/g: (E) 0.1-15 parts by weight of a Ti chelate compound catalyst. Said composition in accordance with the present invention has a low viscosity before solidification; after the solidification, there is produced a composition that exhibits high sealing property and moderate rubber intensity, and excellent stripping performances due to the balance of the performances.

Description

Room temperature hardening polyorganosiloxane composition

The present invention relates to a polyorganosiloxane composition composed of a polyoxyxene elastomer which is hardened at room temperature, and particularly relates to a composition having a low viscosity before curing, and imparting good physical properties after hardening, particularly high. A room temperature curable polyorganosiloxane composition having a cured product which is excellent in peeling property from the adhesion surface of the substrate.

The composition of the curable polyorganosiloxane which is crosslinked by moisture is excellent in heat resistance, adhesion, and electrical properties, and can be used in sealing materials for building materials, electrical and electronic fields, and transportation. Various fields such as adhesives in the machine field.

The curable polyorganosiloxane composition is widely used in the field of electric and electronic applications for coating electrodes and circuit boards, and it is required that the composition before curing has a low viscosity, and the cured product and the substrate have good adhesion after curing. However, in recent years, in the field of electrode coating of LCD panels, it is necessary to remove and peel the cured product from the adhesive surface of the substrate due to repair of the completed LCD panel, and in this case, it is required that no hardened material remains on the surface of the substrate. The interface is peeled off.

In order to solve this problem, Japanese Laid-Open Patent Publication No. 2005-082734 (Patent Document 1) uses a polyorganomethoxy oxane blocked with a dialkoxy monoorganoalkylene group at both ends or a trialkoxy group at both ends. Alkyl-blocked polyorganosiloxane, as a matrix polymer, by using it as a filler with a polyorganosiloxane having no sterol group, trialkoxy or dialkoxy group The selected combination of the treated cerium oxide, the alkoxy decane which is a bifunctional group as a crosslinking agent, or a partial hydrolysis condensate thereof, and the titanium caliper catalyst can be expected to have both adhesion and peelability.

However, when the inventors of the present invention repeated the experiment, according to the technique of Patent Document 1, a composition having a certain degree of adhesion and releasability was confirmed, but it was confirmed that the surface of the cured product contained no sterol group or trioxane. The polyorganosiloxanes of the oxy group and the dialkoxy group bleed out from the hardened material. In addition, the alkoxysilane having a bifunctional group as a crosslinking agent or a partially hydrolyzed condensate thereof increases the crosslinking density of the cured product and lowers the elongation, and the cured product is broken at the time of peeling, and the peeling property cannot be satisfied.

[Patent Document 1] Japanese Laid-Open Patent Publication No. 2005-082734

In view of the above, the present invention provides a composition having a low viscosity before curing, and imparts good physical properties after hardening, in particular, room temperature hardening of a cured product having high elongation and good adhesion to a substrate. A polyorganosiloxane composition for the purpose.

The inventors of the present invention reviewed the results of obtaining a room temperature curable polyorganosiloxane composition having the above object, and found that the polyorganosiloxane having both ends blocked by a trialkoxyalkylene group and two ends were The alkoxy monoorganoalkylene group-blocked polyorganosiloxane is very effective in combination as a polyalkylene oxide having a monoalkyloxy group as a single terminal of a crosslinking agent, and thus the present invention has been completed.

That is, the present invention provides (A) a viscosity of 0.1 to 1,000 Pa at 25 ° C. Polyorganosiloxane having a terminal of s blocked by a trialkoxyalkylene group: 5 to 95% by mass; (B) having a viscosity of 0.1 to 1,000 Pa at 25 ° C. a polyorganosiloxane having a terminal of s blocked by a dialkoxy monoorganoalkylene group: 95 to 5% by mass; and 100 parts by mass of the polyorganosiloxane having a (C) general formula ( 1) (wherein R ¹ , R ² and R ³ are a monovalent saturated hydrocarbon group, X is an oxygen atom or a divalent hydrocarbon group, and n is a positive number which can be 0.005 to 100 Pa.s at a viscosity of 25 ° C, preferably less than The positive viscosity of the ingredients (A) and (B) used.)

The poly-organomethoxy siloxane hardener represented by the single-end trialkoxy group: 1 to 50 parts by mass; (D) the cerium oxide powder having a specific surface area of 50 m ² /g or more: 1 to 50 parts by mass; Titanium clamp catalyst: 0.1 to 15 parts by mass; a room temperature curable polyorganosiloxane composition having an essential component.

In the present invention, by using the so-called (A) component, the terminal trifunctional group of the component (B), and the bifunctional polymer, moderate rubber strength is found by combining these with a single terminal trifunctional alkoxy group. The decane cross-linking agent (C) and the cerium oxide powder (D) are blended, and it is found that the composition before hardening has a low viscosity, and the properties after hardening have high adhesion, and the balance of these can be used to produce excellent peelability. Hardened material.

The polyorganosiloxane which is used in the components (A) and (B) of the present invention is a matrix polymer constituting the present composition, and a polyorganohydrazide in which (A) is blocked by a trialkoxyalkylene group at both ends is prepared. a polyorganosiloxane having two ends terminated by a dialkoxy monoorganoalkylene group, and the (B) component is 95 to 5 masses for the component (A) in an amount of 5 to 95% by mass. % is more preferably 10 to 90% by mass of the component (A), and the component (B) is 90 to 10% by mass. When the component (A) is less than 5% by mass, the interfacial peelability from the substrate is poor, and if it exceeds 95% by mass, the elongation is lowered. The preparation method of such a polyorganosiloxane is very familiar, for example, a polydiorganomethoxy oxane having a hydroxydecyl group is condensed with a tetraalkoxy decane or an alkenyl trialkoxy decane at both ends of the molecular chain. The method of addition reaction of a polydiorganomethoxy oxane having an alkenyl fluorenyl group with a trialkoxy decane or an alkyl dialkoxy decane at both ends of the molecular chain.

The components (A) and (B) are not particularly limited as long as they are a terminal structure, and it is sufficient to impart a bond to the ruthenium atom by curing a general linear polydiorganosiloxane or the like. a monovalent hydrocarbon group having 1 to 8 carbon atoms such as an alkyl group, a cycloalkyl group, an alkenyl group or an aromatic group, or a chloromethyl group or a trifluoromethyl group in which a part or all of the hydrogen atoms of these monovalent hydrocarbon groups are substituted by a halogen atom. A halogenated hydrocarbon group or the like.

The (A) component has a viscosity of 0.1 to 1,000 Pa at 25 ° C. s, ideally 0.2~100 Pa. s. If it is less than 0.1 Pa. s, the rubber is low elongation and brittle, and the interfacial peelability is deteriorated. Moreover, if it is higher than 1,000Pa. The high viscosity of s, the operability is worse. Further, in the present invention, the viscosity is based on the viscosity value of the rotational viscometer.

The (B) component has a viscosity of 0.1 to 1,000 Pa at 25 ° C. s, ideally 0.2~100 Pa. s. If it is less than 0.1 Pa. s, the rubber is low elongation and brittle, and the interfacial peelability is deteriorated. Moreover, if it is higher than 1,000Pa. The high viscosity of s, the operability is worse.

In this case, a polyorganosiloxane represented by the following formula (2) is used as the component (A), and a polyorganosiloxane is represented by the following formula (3) as the component (B). .

In this case, R ¹¹ and R ¹³ are the same or different alkyl groups having 1 to 4 carbon atoms, and particularly preferably a methyl group or an ethyl group. R ¹² , R ¹⁴ and R ¹⁵ are the same or different monovalent hydrocarbon groups or halogenated hydrocarbon groups having 1 to 8 carbon atoms, and particularly preferably R ¹⁴ is an alkyl group. a is such that the polyorganosiloxane of formula (2) has a viscosity of 0.1 to 1,000 Pa at 25 ° C. The number of s, b is such that the polyorganosiloxane of formula (3) has a viscosity of 0.1 to 1,000 Pa at 25 ° C. The number of s.

Further, the viscosity of the component (A) and the component (B) may be either higher or the same, and it is preferred that the component (B) has a high viscosity.

The one-terminal trialkoxy polyorganosiloxane which is used in the component (C) of the present invention, which is such that the elongation of the cured product is increased, is represented by the following formula (1).

(wherein R ¹ , R ² and R ³ are a monovalent saturated hydrocarbon group, X is an oxygen atom or a divalent hydrocarbon group, and n is a positive number which can be 0.005 to 100 Pa.s at a viscosity of 25 ° C, preferably less than The positive viscosity of the ingredients (A) and (B) used.)

Here, the monovalent saturated hydrocarbon group is preferably an alkyl group having 1 to 4 carbon atoms, and is preferably a divalent hydrocarbon group such as an alkylene group having 1 to 4 carbon atoms. It is more desirable to have side chains and (A) and (B). Further, the component (C) preferably has a viscosity at 25 ° C lower than that of any of the components (A) and (B). Further, the viscosity of both the component (A) and the component (B) is preferably lower than that of the component (B). When the viscosity of the component (C) is higher than the viscosity of the component (A) and the component (B), the handling property may be deteriorated. Specifically, the preferred (C) component has a viscosity of 0.005 to 100 Pa. s, especially 0.01~10Pa. s.

The component (C) functions as a crosslinking agent, and 1 to 50 parts by mass is used for a total of 100 parts by mass of the components (A) and (B). When the amount is less than 1 part by mass, sufficient adhesion and elongation cannot be obtained, and if it exceeds 50 parts by mass, the rubber strength is lowered and the interfacial peeling property is lowered. More preferably, it is 3 to 30 parts by mass.

The cerium oxide used in the component (D) of the present invention is a cerium oxide powder having a specific surface area of 50 m ² /g or more, a fumed cerium oxide, a calcined cerium oxide or an organic chlorine group on the surface thereof. Surface treatments of conventional treatment agents such as decanes, polyorganomethoxyoxanes, and organic sulfoniums are preferred. The specific surface area here is based on the BET method. It is preferred to treat the organic sulfonium alkane. More preferably, the amount of carbon treated with an organic sulfonium alkane is 2% by mass or more, particularly 2.0 to 5.0% by mass, of a fumed cerium oxide.

The component (D) is used in an amount of 1 to 50 parts by mass, preferably 3 to 30 parts by mass, based on 100 parts by mass of the components (A) and (B).

A titanium clamp catalyst for use in the component (E) of the present invention, for example, isopropoxy bis(acetic acid ethyl acetate) titanium, isopropoxy bis(acetic acid methyl acetate) titanium, diisopropyloxy Various conventional titanium tongs such as titanium (acetone acetonide) titanium, diisobutoxy bis(acetic acid ethyl acetate) titanium, dimethoxy bis(acetic acid ethyl acetate) titanium, and the like.

The component (E) is used in an amount of 0.1 to 15 parts by mass, particularly 0.3 to 10 parts by mass, based on 100 parts by mass of the components (A) and (B).

The composition of the present invention is composed of the above-mentioned components (A) to (E), and further, in the above-mentioned components, quartz fine powder, carbon black, calcium carbonate, or the like may be added without detracting from the object of the present invention. Inorganic filler, hydrophobized treatment of these, thixotropy-imparting agent, viscosity modifier, fluidity regulator, pigment, heat-resistant agent, flame retardant, organic solvent, anti-mold agent, antibacterial agent, Various additives such as an ultraviolet absorber, a heat resistance improver, a flame retardant, and an adhesion improver.

In the composition of the present invention, the above-mentioned (A) to (E) components are generally used in a kneading machine such as a Shinagawa mixer, a planetary mixer, or a jet mixer, and are preferably kneaded in a water-free state for use in electric electronics. The electrode of the field, the application of the circuit board, and the like, in particular, the electrode coating for the LCD panel, when used for such a use, is applied to a thickness of 0.2 to 1.0 mm, and is placed in the atmosphere at room temperature, for example. It is hardened and used at 23 ° C, 50% RH, and 24 hours of hardening conditions.

[Examples]

Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited to the following examples. Further, in the examples, "parts" means parts by mass. Further, the viscosity indicates a value measured at 25 ° C by a rotational viscometer.

[Example 1]

Polymer (A) (Polydimethyl group blocked by trimethoxydecyl group at both ends of a dealcoholization condensation reaction between polydimethyl methoxy oxane having a hydroxy decyl group and tetramethoxy decane at both ends of the molecular chain Oxane (viscosity 1 Pa.s at 25 ° C)) 50 parts, polymer (B) (Polydimethyloxane and methyltrimethoxydecane having a hydroxyalkyl group at both ends of the molecular chain) Polydimethyl methoxy oxane (viscosity 1 Pa.s at 25 ° C) blocked by methyldimethoxy fluorenyl at both ends of the dealcoholization condensation reaction, 50 parts, hardener (C) (single-terminal trimethoxy) Polydimethyl oxane (viscosity 0.02 Pa.s at 25 ° C)) 10 parts, dry oxidized surface treated with hexamethyldioxane according to BET method with a specific surface area of 200 m ² /g 15 parts of cerium (cerium oxide A) was mixed at room temperature under a reduced pressure of 40 mmHg for 30 minutes.

To the mixture, 1 part of a titanium clamp catalyst (E) (diisopropoxy bis(acetic acid ethyl acetate) titanium) was added, and it was mixed until it was blocked by moisture.

[Embodiment 2]

In 30 parts of the polymer (A) used in Example 1, 70 parts of the polymer (B), 5 parts of the curing agent (C), and 10 parts of cerium oxide A were mixed, and mixed at room temperature under a reduced pressure of 40 mmHg. minute.

To the mixture, 1 part of a titanium clamp catalyst (E) (diisopropoxy bis(acetic acid ethyl acetate) titanium) was added, and it was mixed until it was blocked by moisture.

[Example 3]

In 50 parts of the polymer (A) used in Example 1, 50 parts of the polymer (B), 10 parts of the hardener (C), and a specific surface area of 130 m ² /g according to the BET method were used to prepare dimethyldichloromethane. 15 parts of the surface-treated dry cerium oxide (cerium oxide B) was mixed at room temperature under a reduced pressure of 40 mmHg for 30 minutes.

To the mixture, 1 part of a titanium clamp catalyst (E) (diisopropoxy bis(acetic acid ethyl acetate) titanium) was added, and it was mixed until it was blocked by moisture.

[Comparative Example 1]

In Example 1, the composition was prepared in the same manner except that the hardener (C) was not blended.

[Comparative Example 2]

In Example 1, the composition was prepared in the same manner except that the polymer (B) was not used, 100 parts of the polymer (A) was used, and the curing agent (C) was not blended.

[Comparative Example 3]

In Example 1, the composition was prepared in the same manner except that the methyltrimethoxydecane-substituted hardener (C) was blended.

[Comparative Example 4]

In 50 parts of the polymer (A) used in Example 1, 50 parts of the polymer (B), polyoxyxylene oil (polydimethyl methoxy oxane blocked at both ends by trimethyl decyl group (at 25 ° C) 30 parts of viscosity 0.9 Pa.s)), 10 parts of dimethyldimethoxydecane as a curing agent, and 15 parts of cerium oxide A were mixed at room temperature under a reduced pressure of 40 mmHg for 30 minutes.

To the mixture, 1 part of a titanium clamp catalyst (E) was added, and it was mixed until it was blocked by moisture.

The measurement results of the viscosity of the composition obtained above are shown in Table 1. Further, a mold having a thickness of 2 mm was placed on a glass plate, and the above composition was poured thereinto, and hardened at 23 ° C and 50% RH for 7 days to obtain a cured product having a thickness of 2 mm. The interfacial peeling rate from the glass plate and the elongation at the time of fracture of the cured product according to JIS K6249 were measured. Further, a bead composition having a thickness of 0.5 mm, a width of 1 mm, and a length of 50 mm was cured on a glass plate at 23 ° C and 50% RH for 7 days to obtain a cured product. On the other hand, the rubber and the glass were peeled off by an automatic mapper, and the bead peeling rate at this time was evaluated. Further, the 2 mm thick cured product (50 mm × 50 mm in length and width) obtained above was allowed to stand on a wrapping paper at 23 ° C for 7 days to visually observe the bleeding of the oil on the coated paper. The results are shown in Table 1.

Claims (1)

A room temperature curable polyorganosiloxane composition characterized by having a viscosity of (A) at 25 ° C of 0.1 to 1,000 Pa. Polyorganosiloxane having a terminal of s blocked by a trialkoxyalkylene group: 5 to 95% by mass; (B) having a viscosity of 0.1 to 1,000 Pa at 25 ° C. a polyorganomethoxy siloxane having a polyalkyl oxa oxane blocked by a dialkoxy monoorganoalkylene group at 95% by mass of both ends, (C) general formula (1) ) (wherein, R ¹ , R ² and R ³ are a monovalent saturated hydrocarbon group, X is an oxygen atom or a divalent hydrocarbon group, and n is a positive number which can be a positive number of 0.005 to 100 Pa.s at a viscosity of 25 ° C) 1 to 50 parts by mass of a trialkoxy polyorganomethoxy siloxane hardener; (D) cerium oxide powder having a specific surface area of 50 m ² /g or more: 1 to 50 parts by mass; (E) titanium tong catalyst : 0.1 to 15 parts by mass; is an essential component (except that it does not include the general formula (A') (wherein R ^{1 is} a group selected from a monovalent hydrocarbon group, a halogenated hydrocarbon group, and a cyanoalkyl group, R ² is an alkyl group, X is an oxygen atom or a divalent hydrocarbon group, and n is a viscosity at 25 ° C a positive number of 20~1,000,000 cP) and / or (wherein R ^{1 is} a group selected from a monovalent hydrocarbon group, a halogenated hydrocarbon group, and a cyanoalkyl group, R ² is an alkyl group, X is an oxygen atom or a divalent hydrocarbon group, and n is a viscosity at 25 ° C (Ordinary number of 20~1,000,000 cP) of the diorganopolyoxyalkylene, (B') general formula (wherein R ^{1 is} a group selected from a monovalent hydrocarbon group, a halogenated hydrocarbon group, and a cyanoalkyl group, R ² is an alkyl group, X is an oxygen atom or a divalent hydrocarbon group, and m is a viscosity at 25 ° C 20~1,000,000 cP, and does not reach the positive value of the viscosity of the (A') component) and / or (wherein R ^{1 is} a group selected from a monovalent hydrocarbon group, a halogenated hydrocarbon group, and a cyanoalkyl group, R ² is an alkyl group, X is an oxygen atom or a divalent hydrocarbon group, and m is a viscosity at 25 ° C 20 to 1,000,000 cP, and a positive number of the viscosity of the component (A') is not shown.) The diorganopolyoxyalkylene: (A') + (B') is 100 parts by weight in total; (C') specific surface area is More than 50 m ² /g of cerium oxide powder: 1 to 50 parts by weight; (D') general formula R ³ _a Si(OR ⁴ ) _4-a (wherein R ³ is a monovalent hydrocarbon group, and R ⁴ is an alkyl group Or an alkoxy-substituted alkyl group, a is an alkoxydecane represented by 0, 1 or 2) or a partially hydrolyzed condensate thereof: 0.5 to 15 parts by weight; (E) a titanium clamp catalyst: 0.1~ 10 parts by weight; a room temperature hardening polyorganosiloxane composition).