阅读说明：本技术 一种用于合成kh-560硅烷偶联剂的固载型催化剂及其制备方法 (Immobilized catalyst for synthesizing KH-560 silane coupling agent and preparation method thereof ) 是由 陈超 梁秋鸿 史顺利 赵丹 汪淑华 张宁 于 2020-03-16 设计创作，主要内容包括：本发明公开了一种用于合成KH-560硅烷偶联剂的固载型催化剂及其制备方法,包括：S1以氨基功能化的MOFs为底物,通过席夫碱反应或酰胺化反应将多齿N/O杂合配体修饰在MOFs孔道内,得到具有双齿功能配体修饰的MOFs；S2将后修饰的MOFs粉体浸入特定溶剂中,加入辅助配体和缚酸剂,搅拌回流；缓慢滴加一定计量的氯铂酸甲醇溶液后继续回流,并将回流后所得产品离心后真空干燥,得到Pt/MOFs催化剂。该固载型Pt/MOFs催化剂具有较高催化活性的同时,可多次循环重复使用,解决了现有制备方法催化剂分离困难及反应废液带来的环保问题。(The invention discloses an immobilized catalyst for synthesizing a KH-560 silane coupling agent and a preparation method thereof, wherein the immobilized catalyst comprises the following steps: s1, modifying a multidentate N/O hybrid ligand in an MOFs pore channel by taking amino-functionalized MOFs as a substrate through Schiff base reaction or amidation reaction to obtain the MOFs modified by the ligand with the bidentate function; s2, immersing the post-modified MOFs powder into a specific solvent, adding an auxiliary ligand and an acid-binding agent, and stirring and refluxing; slowly dripping a certain amount of chloroplatinic acid methanol solution, continuously refluxing, centrifuging the product obtained after refluxing, and drying in vacuum to obtain the Pt/MOFs catalyst. The immobilized Pt/MOFs catalyst has high catalytic activity, can be recycled repeatedly, and solves the problems of difficult separation of the catalyst and environmental protection brought by reaction waste liquid in the existing preparation method.)

1. A preparation method of an immobilized catalyst for synthesizing a KH-560 silane coupling agent is characterized by comprising the following steps:

s1, modifying a multidentate N/O hybrid ligand in an MOFs pore channel by taking amino-functionalized MOFs as a substrate through Schiff base reaction or amidation reaction to obtain the MOFs modified by the ligand with the bidentate function;

s2, immersing the post-modified MOFs powder into a specific solvent, adding an auxiliary ligand and an acid-binding agent, and stirring and refluxing; slowly dripping a certain amount of chloroplatinic acid methanol solution, continuously refluxing, centrifuging the product obtained after refluxing, and drying in vacuum to obtain the Pt/MOFs catalyst.

2. The method of claim 1, wherein in step S1, the MOFs with amino functionalization is MiL-101-NH₂、UiO-66-NH₂Or IRMOF-3; the N/O hybrid ligand is salicylaldehyde or piperazine anhydride.

3. The production method according to claim 1, wherein in step S2, the specific solvent is toluene, THF, or methanol; the auxiliary ligand is one or more of acetylacetone, n-butanol or isobutanol; the acid-binding agent is triethanolamine.

4. The method of claim 3, wherein in step S2, the molar ratio of the modified MOFs powder to the chloroplatinic acid to the ancillary ligand to the acid-binding agent is 1: 0.1-1.0: 0.5-2.0.

5. The method of claim 1 or 2 or 3 or 4, wherein the schiff base reaction or amidation reaction of step S1 is preceded by the step of activating MOFs:

soaking MOFs powder in a specific solvent for a certain time, periodically replacing the specific solvent, centrifuging and drying a product obtained after soaking to obtain activated MOFs; the specific solvent is toluene, THF or methanol.

6. The production method according to claim 5, characterized by comprising, in step S1:

adding activated MOFs powder and an N/O hybrid ligand into a specific solvent, heating and refluxing for 12h to obtain the MOFs modified by the ligand with the bidentate function, wherein the feeding molar ratio of the MOFs powder to the N/O hybrid ligand is 1: 1-10, and the molar mass of the MOFs powder is-NH₂And (4) counting groups.

7. A preparation method of KH-560, which is characterized by comprising the following steps:

KH-560 is prepared by using allyl glycidyl ether and trimethoxysilane as raw materials, using Pt/MOFs catalyst prepared by the method for preparing the supported catalyst according to any one of claims 1 to 6 as a catalyst, and simultaneously dropwise adding and stirring the allyl glycidyl ether and the trimethoxysilane.

8. The KH-560 preparation method of claim 7, wherein the molar ratio of allyl glycidyl ether, trimethoxysilane and Pt/MOFs catalyst is 1:1: 0.001-0.005, wherein the molar mass of MOFs powder is-NH₂And (4) counting groups.

9. The process of claim 7 or 8, wherein the KH-560 is prepared by introducing 2bar of nitrogen at 80-90 ℃ for 2-6 hours during the catalytic reaction for preparing KH-560.

10. The immobilized catalyst for synthesizing the KH-560 silane coupling agent is characterized by comprising MOFs and a Pt complex anchored in the MOFs pore channels, and the specific structure is as follows:

Technical Field

The invention relates to the technical field of catalyst preparation, in particular to an immobilized catalyst for synthesizing a KH-560 silane coupling agent and a preparation method thereof.

Background

KH-560 is one of the main species of silane coupling agents (chemical name: gamma-glycidoxypropyltrimethylsilane, corresponding to the trade name: KH-560 (Zhongkojic) or A-187 (United states Co., Ltd.)) due to the epoxy group and hydrolyzable-OCH₃The group makes it have special crosslinking performance, and is widely applied to the bonding modification of organic high molecular materials or inorganic fillers and the mechanical strength enhancement of composite materials so as to improve the wet electrical insulation performance of integrated circuit materials and printed circuit boards.

KH-560 is synthesized by hydrosilylation with allyl glycidyl ether and trimethoxy silane as raw materials under the action of catalyst. For example, in the synthesis of KH-560 by using chloroplatinic acid-isopropanol as a catalyst and methanol as a solvent, the yield reaches 90%, as disclosed in U.S. Pat. No. 4,983,981; the Chinese patent 201811616847.7 takes rhodium complex as catalyst and target product as solvent to prepare KH-560, the yield can reach 95% at most; the Chinese patent 201410372177.4 takes ruthenium trichloride complex as a catalyst and toluene as a solvent, and the yield reaches 92-96 percent. Although many schemes in the current industrial production can effectively synthesize KH-560, a catalytic system mainly adopts a homogeneous precious metal catalyst, and although the effect of the homogeneous catalyst is good, the problems that the catalyst is difficult to separate, cannot be recycled, and the pollution of reaction waste liquid is serious exist, so that the further application of the industrial production is severely restricted. Therefore, heterogenization of homogeneous catalysts, i.e., preparation of supported noble metal catalysts, has been receiving increasing attention. For example, the document doi:10.1002/aoc.4874 reports that a platinum metal Schiff base complex is anchored on a mesoporous molecular sieve SBA-15 for catalytic synthesis of KH-560, and the conversion rate reaches 86%; 10.1016/j.jorganchem.2011.02.021, with aminomethoxysilane, the catalyst showed only a 7% (94% to 87%) drop in yield after five cycles with platinum metal anchored on the silica foam; the document doi 10.4028/www.scientific.net/AMR.233-235.1544 uses a platinum/carbon catalyst as a catalyst, although the conversion rate is as high as 97%, the recycling performance is poor.

It can be seen that, although the heterogeneous catalysis can well reduce the usage amount and recovery difficulty of the noble metal catalyst, there are various problems to be solved, such as disordered activated carbon, mesoporous silica or alumina with a small specific surface as the carrier, low catalytic efficiency, low catalytic selectivity, etc.

Disclosure of Invention

The invention aims to provide an immobilized catalyst for synthesizing a KH-560 silane coupling agent and a preparation method thereof, and effectively solves the technical problems of low catalytic efficiency, low circulation efficiency and the like of the existing catalyst.

The technical scheme provided by the invention is as follows:

a preparation method of an immobilized catalyst for synthesizing a KH-560 silane coupling agent comprises the following steps:

s1, modifying a multidentate N/O hybrid ligand in an MOFs pore channel by taking amino-functionalized MOFs as a substrate through Schiff base reaction or amidation reaction to obtain the MOFs modified by the ligand with the bidentate function;

s2, immersing the post-modified MOFs powder into a specific solvent, adding an auxiliary ligand and an acid-binding agent, and stirring and refluxing; slowly dripping a certain amount of chloroplatinic acid methanol solution, continuously refluxing, centrifuging the product obtained after refluxing, and drying in vacuum to obtain the Pt/MOFs catalyst.

In the technical scheme, the MOFs is a crystalline ordered pore channel structure material formed by self-assembling inorganic metal ions and organic functional groups through covalent bonds, the crystalline ordered pore channel structure material not only has a crystal structure similar to a zeolite molecular sieve, but also has a larger specific surface area compared with the molecular sieve, and a pore channel has designability and cuttability, and the material is easier to functionalize, so that the amino functionalized MOFs are selected as a solid substrate or a carrier for efficient selective catalytic reaction.

The invention also provides a preparation method of KH-560, which comprises the following steps:

KH-560 is prepared by using allyl glycidyl ether and trimethoxysilane as raw materials, using Pt/MOFs catalyst prepared by the method for preparing the supported catalyst according to any one of claims 1 to 6 as a catalyst, and simultaneously dropwise adding and stirring the allyl glycidyl ether and the trimethoxysilane.

The invention also provides an immobilized catalyst for synthesizing the KH-560 silane coupling agent, which comprises MOFs and a Pt complex anchored in the pore channels of the MOFs, and the specific structure is as follows:

the immobilized catalyst for synthesizing the KH-560 silane coupling agent and the preparation method thereof provided by the invention are prepared by taking amino functionalized MOFs as a substrate and anchoring a Pt metal complex in a pore channel of the substrate through a chemical bond, and the immobilized Pt/MOFs catalyst has high catalytic activity and can be recycled for multiple times, thereby solving the problems of difficult separation of the catalyst and environmental protection brought by reaction waste liquid in the existing preparation method; meanwhile, the shape selection capability of the MOFs pore canal greatly reduces the isomeric byproducts, thereby greatly improving the production efficiency. In addition, the process route has simple process, can prepare the KH-560 silane coupling agent with stable quality, high yield and relatively low cost, and has larger industrial production potential.

Drawings

The foregoing features, technical features, advantages and embodiments are further described in the following detailed description of the preferred embodiments, which is to be read in connection with the accompanying drawings.

FIG. 1 is a schematic flow chart of the preparation method of the supported catalyst for synthesizing KH-560 silane coupling agent in the invention.

Detailed Description

The essence of the invention is further illustrated below with reference to the figures and examples, but the invention is not limited thereto.

Aiming at the technical problems of low catalytic efficiency, low cycle efficiency and the like of the existing catalyst, the invention provides a brand-new preparation method of an immobilized catalyst for synthesizing a KH-560 silane coupling agent, as shown in figure 1, and in one embodiment, the preparation method comprises the following steps:

s1 takes amino-functionalized MOFs as a substrate, and modifies the multidentate N/O hybrid ligand in the MOFs pore channel through Schiff base reaction or amidation reaction to obtain the MOFs modified by the ligand with bidentate function. Specifically, the amino-functionalized MOFs is MiL-101-NH₂、UiO-66-NH₂Or IRMOF-3; the N/O hybrid ligand is salicylaldehyde or piperazine anhydride.

S2, immersing the post-modified MOFs powder into a specific solvent, adding an auxiliary ligand and an acid-binding agent, and stirring and refluxing; slowly dripping a certain amount of chloroplatinic acid methanol solution, continuously refluxing, centrifuging the product obtained after refluxing, and drying in vacuum to obtain the Pt/MOFs catalyst, wherein the structure is as follows:

specifically, the specific solvent is toluene, THF or methanol; the auxiliary ligand is one or more of acetylacetone, n-butanol or isobutanol; the acid-binding agent is triethanolamine, and the molar ratio of the modified MOFs powder, the chloroplatinic acid, the auxiliary ligand and the acid-binding agent is 1: 0.1-1.0: 0.5-2.0.

Before the schiff base reaction or amidation reaction in step S1, the method further comprises the step of activating the MOFs: soaking MOFs powder in a specific solvent for a certain time, periodically replacing the specific solvent, centrifuging and drying a product obtained after soaking to obtain activated MOFs; particular solvents are toluene, THF or methanol. Specifically, activated MOFs powder and an N/O hybrid ligand are added into a specific solvent, heating and refluxing are carried out for 12 hours to obtain MOFs modified by the ligand with a bidentate function, wherein the feeding molar ratio of the MOFs powder to the N/O hybrid ligand is 1: 1-10, and the molar mass of the MOFs powder is-NH₂And (4) counting groups.

Based on the Pt/MOFs catalyst prepared by the embodiment, the invention also provides a KH-560 preparation method, which comprises the following steps: the method takes allyl glycidyl ether and trimethoxy silane as raw materials, takes the Pt/MOFs catalyst prepared by the method as a catalyst, and synchronously dropwise adds and stirs allylKH-560 is prepared by reacting a glycidylether with trimethoxysilane. In the process, 2bar of nitrogen is filled, the reaction temperature is 80-90 ℃, the reaction time is 2-6h, the molar ratio of allyl glycidyl ether, trimethoxy silane and Pt/MOFs catalyst is 1:1: 0.001-0.005, wherein the molar mass of the MOFs powder is-NH₂And (4) counting groups.

The invention is described in further detail below by way of examples: