KR-102961315-B1 - Thermally initiated acid-catalyzed reaction between silyl hydride and silyl ether and/or silanol

KR102961315B1KR 102961315 B1KR102961315 B1KR 102961315B1KR-102961315-B1

Abstract

The composition contains a mixture of a silyl hydride, a silanol and/or silyl ether, a Lewis acid catalyst, and an amine having the following chemical formula: R1 R2 R3 N (wherein nitrogen is not a member of the N=CN linkage, and each of R1 , R2 , and R3 is independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, and conjugated moiety; at least one of R1 , R2 , and R3 is a conjugated moiety connected to nitrogen by a conjugated carbon).

Inventors

웨이, 얀후
스위어, 스티븐
니우, 젠빈
라우, 난구오

Assignees

다우 실리콘즈 코포레이션

Dates

Publication Date: 20260508
Application Date: 20200602
Priority Date: 20190604

Claims (10)

A composition comprising a mixture of silyl hydride, silanol and/or silyl ether, a Lewis acid catalyst, and an amine, The above amine has the chemical formula R1R2R3N (wherein the nitrogen is not a member of the N=CN linkage, and each of R1 , R2 , and R3 is independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, and conjugated moiety; at least one of R1 , R2 , and R3 is a conjugated moiety connected to the nitrogen by a conjugated carbon), and A composition in which the above amine is selected from the group consisting of aniline, 4-methylaniline, 4-fluoroaniline, 2-chloro-4-fluoroaniline, diphenylamine, diphenylmethylamine, triphenylamine, 1-naphthylamine, 2-naphthylamine, 1-aminoanthracene, 2-aminoanthracene, 9-aminoanthracene, β-aminostyrene, 1,3,5-hexatriene-1-amine, N,N-dimethyl-1,3,5-hexatriene-1-amine, 3-amino-2-propenal, and 4-amino-3-buten-2-one.
◈Claim 2 was waived upon payment of the establishment registration fee.◈ A composition according to claim 1, wherein the conjugated moiety is an aromatic moiety.
◈Claim 3 was waived upon payment of the establishment registration fee.◈ A composition according to claim 1, wherein at least two of R1, R2, and R3 are conjugated moiety attached to N through conjugated carbon.
◈Claim 4 was waived upon payment of the establishment registration fee.◈ A composition according to claim 1, wherein the Lewis acid catalyst is selected from the group consisting of aluminum alkyl, aluminum aryl, aryl boran, fluorinated aryl boran, boron halide, aluminum halide, gallium alkyl, gallium aryl, gallium halide, silyllium cation, and phosphonium cation.
◈Claim 5 was waived upon payment of the establishment registration fee.◈ In paragraph 4, the composition wherein the Lewis acid catalyst is a fluorinated aryl borane.
A composition according to any one of claims 1 to 5, wherein the silyl hydride and the silanol and/or silyl ether are the same molecule.
A composition according to any one of claims 1 to 5, wherein the composition is free of a UV photosensitive blocking agent for the Lewis acid catalyst.
(a) a step of providing a composition of any one of claims 1 to 5; and (b) a method comprising the step of heating the composition to a temperature sufficient to dissociate the Lewis acid catalyst from the amine.
◈Claim 9 was waived upon payment of the establishment registration fee.◈ A method according to claim 8, wherein step (a) comprises mixing an amine, a Lewis acid catalyst, a silyl hydride, and a silanol and/or silyl ether together, provided that the Lewis acid catalyst and the amine are combined such that, before combining them with both the silyl hydride and the silanol and/or silyl ether, the amine is complexed with the Lewis acid to block the catalytic activity of the Lewis acid.
The method of claim 8 further comprises the step of applying the composition to a substrate or placing the composition in a mold after step (a) and before or during step (b).

Description

Thermally initiated acid-catalyzed reaction between silyl hydride and silyl ether and/or silanol The present invention relates to a composition comprising a silyl hydride, a silyl ether and/or silanol, a Lewis acid catalyst, and an amine blocking agent for the Lewis acid catalyst. When the composition is heated, the Lewis acid catalyst is released from the amine blocking agent, which can induce a reaction between the silyl hydride and the silyl ether and/or silanol. introduction Strong Lewis acids are known catalysts for a number of reactions. For example, the Piers-Rubinstein (PR) reaction between a silyl hydride and a silyl ether is a well-known reaction catalyzed by a strong Lewis acid, in particular tris(pentafluorophenyl)borane ("BCF"). Similar Lewis acid-catalyzed reactions include rearrangement reactions between silyl hydrides and polysiloxanes, as well as between silyl hydrides and silanols. For example, see the literature [Chem. Eur. J. 2018, 24, 8458-8469]. Lewis acid catalytic reactions, such as PR reactions, tend to be rapid even at 23°C. The high reactivity of these reaction systems limits their applications. While the reaction may be desirable in applications such as coatings and adhesives, the system must be stored in a multi-part system to prevent the reaction before application. Even so, once the components are combined, the reaction can occur so rapidly that there is little time to apply the reactive system. It is desirable to identify a method to control the Lewis acid catalytic reaction and provide it as a one-part system containing the reactants and the Lewis acid catalyst in a form that is ideally stable at 23°C but can be induced to react when desired. UV photosensitive blocking agents have been combined with Lewis acids to form blocked Lewis acids that release Lewis acids upon exposure to UV light. Upon exposure to UV light, the blocking agent dissociates from the Lewis acid, leaving the Lewis acid in a free state to catalyze the reaction. The challenge with systems containing such blocked Lewis acids is that they need to be kept in a dark room to maintain stability. Additionally, exposure to UV light is required to initiate the reaction, and in the case of concentrated compositions, it can be difficult to obtain UV light penetration to initiate rapid curing throughout the composition. In particular, amines have been examined in conjunction with Lewis acids in PR reaction-type systems. However, amines have been reported to completely inhibit the reaction. For example, see the literature [Chem. Comm. 2010, 46, 4988-4990 at 4988]. Most amines complex with Lewis acid catalysts in an essentially irreversible manner, but triarylamines are an exception and were later found not to impair Lewis acids in catalyzing the PR reaction. See the literature [Chem. Eur. J. 2018, 24, 8458-8469 at 8461 and 8463]. It is desirable to determine a method for preparing a one-part system for a Lewis acid catalytic reaction that is stable at 23°C even when exposed to UV light, but can be induced to react if desired. The present invention provides a solution to the problem of determining a method for preparing a one-part system for a Lewis acid catalytic reaction that is stable at 23°C even when exposed to UV light, but can be induced to react if desired. In particular, the present invention provides a solution to such a problem in the reaction between a silyl hydride and a silanol and/or silyl ether. Furthermore, the present invention provides such a solution that is induced to react when heated to have a preferred 90°C curing rate, i.e., 15 minutes or less, preferably 10 minutes or less, more preferably 5 minutes or less, even more preferably 1 minute or less, most preferably 30 seconds or less. The present invention is the result of the discovery of a specific amine that, surprisingly and unexpectedly, complexes with a Lewis acid catalyst at 23°C to block the activity of the Lewis acid catalyst and form a stable 1-part reactive system, but releases the Lewis acid catalyst upon heating to promote the rapid curing of the 1-part reactive system. Consequently, the specific amine is a thermally induced blocking agent for the Lewis acid catalyst, which blocks the Lewis acid catalyst at 23°C but releases the Lewis acid catalyst to catalyze the reaction at elevated temperatures, such as above 80°C, above 90°C, or above 100°C (generally below 300°C, below 250°C, below 200°C, below 150°C, and even below 100°C). This is surprising considering the prior understanding in the art. As mentioned above, the current understanding is that amines do not irreversibly complex with Lewis acid catalysts or damage Lewis acid catalysts in Lewis acid catalytic reactions. [Chem. Comm. See 2010, 46, 4988-4990 at 4988] and the literature [Chem. Eur. J. 2018, 24, 8458-8469 at 8461 and 8463]. The present discovery regarding an amine acting as a thermally induced blocking agent for a Lewis acid catalyst enables a composition of the present