US-12624056-B2 - Organic titanium compound and curing catalyst

Abstract

Provided are an organic titanium compound and curing catalyst capable of quickly curing a room temperature-curable organopolysiloxane composition when added thereto, and improving an adhesiveness of a cured product of such composition, especially an adhesiveness thereof after being dipped in warm water, while maintaining an unimpaired storage stability. The organic titanium compound is a reaction product of an organooxy group- and chelating ligand-containing organic titanium compound represented by an average composition formula (I) Ti(OR) 4-a (X) a wherein R is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 12 carbon atoms, X is a chelating ligand, a is a number of 0.1 to 3.5; and a fatty acid ester of a polyhydric alcohol.

Inventors

• Taiki Katayama
• Takafumi Sakamoto

Assignees

• SHIN-ETSU CHEMICAL CO., LTD.

Dates

Publication Date

20260512

Application Date

20220120

Priority Date

20210202

Claims (9)

1. 1 . An organic titanium compound as a reaction product of an organooxy group- and chelating ligand-containing organic titanium compound represented by an average composition formula (I) Ti(OR) 4-a (X) a wherein R is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 12 carbon atoms, X is a chelating ligand, a is a number of 0.1 to 3.5; and a fatty acid ester of a polyhydric alcohol.
2. 2 . The organic titanium compound according to claim 1 , wherein in the average composition formula (I), the organooxy group represented by OR is an alkoxy group.
3. 3 . The organic titanium compound according to claim 1 , wherein the chelating ligand is a β-ketoester chelate or a β-diketone chelate.
4. 4 . The organic titanium compound according to claim 1 , wherein the chelating ligand is ethyl acetoacetate chelate (ethyl acetoacetonato) or acetylacetone chelate (acetylacetonato).
5. 5 . The organic titanium compound according to claim 1 , wherein the fatty acid ester of a polyhydric alcohol is a fatty acid ester of ethylene glycol, propylene glycol, glycerol or pentaerythritol.
6. 6 . The organic titanium compound according to claim 1 , wherein the fatty acid ester of a polyhydric alcohol is at least one kind selected from triacetin, diacetin and monoacetin.
7. 7 . The organic titanium compound according to claim 1 , wherein the organic titanium compound is a reaction product in which a molar ratio between the organooxy group- and chelating ligand-containing organic titanium compound (I) represented by the average composition formula (I) and the fatty acid ester of a polyhydric alcohol is [organic titanium compound (I)]:[polyhydric alcohol fatty acid ester]=1:0.1 to 1:3.5.
8. 8 . A curing catalyst for a room temperature-curable resin composition, comprising the organic titanium compound according to claim 1 .
9. 9 . A method for curing a room temperature-curable resin composition, comprising: curing the room temperature-curable resin composition in the presence of the curing catalyst of claim 8 .

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application is a National Stage application of PCT/JP2022/001924, filed Jan. 20, 2022, which claims the benefit of Japanese Application No. 2021-014840, filed Feb. 2, 2021, both of which are incorporated by reference in their entirety herein. TECHNICAL FIELD The present invention relates to a novel organic titanium compound useful as a curing catalyst for a room temperature-curable resin composition; and a curing catalyst comprised of such organic titanium compound. BACKGROUND ART Conventionally, as a curable resin composition yielding an elastomer elastic body (rubber cured product) when cured by cross-linking after undergoing a condensation reaction with water (moisture) in the air at room temperature (23° C.±15° C.), there is known a room temperature-curable resin composition such as a room temperature-curable organopolysiloxane composition. Such room temperature-curable resin composition is widely used in, for example, the construction, transportation, and electrical and electronic parts industries as it is superior in safety as well as durability and adhesiveness as a rubber. Adhesiveness in particular is often considered important because it greatly affects the reliability of the materials in which the composition is used. Among room temperature-curable organopolysiloxane compositions, so-called one-component (one-part type) room temperature-curable organopolysiloxane compositions do not require cumbersome operations such as weighing or mixing a base polymer, a cross-linking material, a catalyst and the like immediately before use, whereby there shall occur no errors when combining the ingredients. Further, in the case of such type of room temperature-curable organopolysiloxane composition, since it generally has an excellent adhesiveness to a wide variety of base materials even when a primer is not used, the composition is widely used as, for example, an elastic adhesive agent or coating material in the electrical and electronics industries or the like, and a sealing material for construction. Such one-component room temperature-curable organopolysiloxane composition is often classified according to a compound released from the composition when it comes into contact with water in the air, typical example of which may include a deacetylation-type, deoximation-type, deamidation-type, dehydroxylamine-type, diacetone-type, and dealcoholization-type organopolysiloxane compositions. Among them, particularly preferred and used are dealcoholization-type organopolysiloxane compositions releasing alcohols when curing takes place, because, for example, these compositions produce less odor, do not corrode metals such as copper and iron, and have an excellent self-adhesiveness (adhesiveness to various base materials after curing when no primer is used) and adhesive durability. However, while a one component- and dealcoholization-type organopolysiloxane composition has the abovementioned excellent properties during a short period of time after production, there have been observed flaws in storage stability such as the fact that, depending on the formulation, the kind of properties that are exhibited immediately after production will no longer be achieved as the time passes by during storage. Further, if stored under direct sunlight at the site of use, or if stored under a high-temperature environment exceeding 50° C. which is often conceivable when, for example, the composition is stored in a container during transportation, there shall occur a problem that, for example, not only there cannot be achieved the kind of properties that are exhibited immediately after production even after a relatively short period of storage, but curing failure may be observed as well. One component- and dealcoholization-type organopolysiloxane compositions have long been proposed; a typical example thereof is a composition comprising an organopolysiloxane with its ends being blocked by hydroxyl groups, alkoxysilane and a titanium compound (Patent document 1). In recent days, in regard to the room temperature-curable organopolysiloxane composition disclosed in Patent document 1, it has been disclosed that a composition further containing a polyhydric alcohol fatty acid ester as typified by triacetin is capable of being turned into a cured product superior in adhesiveness even when no primer is used, and has an excellent storage stability when in a sealed and packaged state (Patent document 2). Further, in Patent document 3, it is disclosed that storage stability can be improved by adding an organic silicon compound having a polyhydric alcohol fatty acid ester structure as typified by triacetin to a room temperature-curable organopolysiloxane composition. PATENT DOCUMENTS Prior Art Documents Patent document 1: Japanese Examined Patent Publication Sho 39-27643Patent document 2: Japanese Patent No. 4775600Patent document 3: Japanese Patent No. 6690704 SUMMARY OF THE INVENTION Problems to be So