CN113234225A

CN113234225A - Method for simply and efficiently preparing T8-POSS

Info

Publication number: CN113234225A
Application number: CN202110650706.2A
Authority: CN
Inventors: 渠源; 孔凡振; 孔令刚; 李杭杭; 曹婷婷; 陈僮; 王国莹
Original assignee: Shandong Guike New Material Co ltd
Current assignee: Shandong Guike New Material Co ltd
Priority date: 2021-06-10
Filing date: 2021-06-10
Publication date: 2021-08-10
Anticipated expiration: 2041-06-10
Also published as: CN113234225B

Abstract

The invention relates to a method for simply and efficiently preparing T8-POSS, which comprises the following steps: trialkoxysilane containing substituent groups is dissolved in an alcohol solvent, then weak base is added, then solvent A and catalyst are added, and then the mixture is transferred into a reaction kettle for solvothermal reaction, so that cage T8-POSS can be generated. The synthesis method of the cage-type T8-POSS provided by the invention is obtained by a solvothermal method, the reaction conditions are easy to control, and the obtained cage-type T8-POSS has a clear structure, high purity and a huge application prospect. The prepared cage type T8-POSS can be directly applied, and can also be used as a raw material for further modification.

Description

Method for simply and efficiently preparing T8-POSS

Technical Field

The invention relates to a simple and efficient method for preparing T8-POSS, belonging to the field of organic silicon polymer synthesis.

Background

Polyhedral oligomeric silsesquioxane (POSS) is an organic-inorganic hybrid molecule with a nanoscale cage-like structure and has excellent physicochemical properties. The hollow rigid structure enables the composite material to have good gas permeability, low dielectric constant and excellent optical performance, the inorganic silica framework enables the composite material to have excellent thermal stability, radiation resistance and oxidation resistance, and meanwhile, the molecular size is in a nanometer scale, so that the composite material has the nanometer effects of surface and interface effect, small-size effect, quantum size effect and the like, shows the special performances of thermodynamics, optics, electrics, magnetism, acoustics and the like, and is widely applied to the fields of heat-resistant flame-retardant materials, dielectric materials, luminescent materials, packaging materials, liquid crystal materials, biomedical materials, insulating materials and the like. The POSS-based new materials were first used by the us air force in the 90's last century. Cage-type phenyl silsesquioxane (T8-POSS) is an important member in the POSS family, and is widely applied to the fields of high temperature resistance, flame retardance and the like by virtue of the rigidity of an aromatic hydrocarbon structure and super excellent thermal stability.

Domestic patent (CN107778794A) discloses a method for preparing T8-POSS, which comprises the steps of dispersing phenyltrichlorosilane serving as a precursor in a benzene solvent, dropwise adding deionized water for 12 hours, standing for 4 days, washing an organic phase to be neutral after liquid separation, adding a methanol solution of benzyl trimethyl ammonium hydroxide, refluxing for 4 hours and 24 hours in a segmented mode, cooling and filtering to obtain a product with the concentration of about 88.2%. Although the reaction conditions are relatively mild, the method is complicated in steps, long in time consumption and difficult to realize batch production.

Foreign literature (Dalton trans, 2003,2945) reports that early studies mainly consisted in hydrolysis of trichlorosilane under strong acid conditions, and strong acid can promote hydrolysis and also lead to decomposition of the generated nanocages, so that the yield is extremely low and the time consumption is extremely long. To make hydrolytic polycondensation more manageable, researchers have turned the precursors to trialkoxysilanes (j.am. chem. soc.,1955,77,3996), reducing the reaction time from months to weeks or days, with the yield gradually increasing to around 30%. However, the yield is still lower, and the tetrabutylammonium fluoride is further used for replacing a strong acid as a catalyst, so that the yield can be effectively improved, 49 percent of T8-POSS can be obtained after the reaction is carried out for about 1 day, and meanwhile, a small amount of T12-POSS is accompanied. Since tetrabutylammonium fluoride contains 5% water, the reaction strongly depends on slightly more toxic tetrahydrofuran as solvent, and the yield is significantly reduced in alcoholic solvents.

Foreign literature (Dalton trans, 2008,5072) reports that the product T8-POSS is obtained at about 72% by weight after refluxing for 48 hours with phenyltrimethoxysilane as precursor, 6% by mass of KF and 1% by molar amount of crown ether (18-crown-6) as dual catalyst, but it uses toluene, which is more toxic, as solvent and requires the use of a more complex Dean-Stark apparatus.

Domestic studies (inorg. chem.,2018,57,13477) reported that using phenylsilane as a precursor, Cs in 1% molar amount₂CO₃As a catalyst, T8-POSS can be prepared quickly and efficiently in a nitrogen-nitrogen dimethylformamide solvent with the yield of about 39%. However, phenylsilane is relatively expensive and the reaction needs to be carried out under an inert gas atmosphere, which limits further applications.

Comprehensive analysis of domestic and foreign research shows that at present, although the application of cage-type T8-POSS is wide, the preparation of cage-type T8-POSS has the defects of long reaction time, low yield, complicated steps, use of organic solvents with high toxicity and the like, and the technology needs to be optimized and improved urgently.

Disclosure of Invention

Aiming at the defects in the preparation of cage T8-POSS at home and abroad, the invention provides a simple and efficient method for preparing T8-POSS, which has the characteristics of short reaction time, high yield and controllable structure and has wide application prospect. The POSS product obtained by the invention can be directly applied, and can also be used for compounding the obtained T8-POSS to obtain the POSS-based composite material, or the group types of the reaction raw materials are changed to obtain the POSS compound with more abundant types, so that the invention has outstanding convenience.

Summary of The Invention

The synthesis method of the cage-type T8-POSS provided by the invention is obtained by a solvothermal method, the reaction conditions are easy to control, and the obtained cage-type T8-POSS has a clear structure, high purity and a huge application prospect. The prepared cage type T8-POSS can be directly applied, and can also be used as a raw material for further modification. The obtained cage type T8-POSS can be further compounded, thereby providing convenience for the preparation of POSS-based composite materials meeting different requirements. By changing the groups of the raw materials, the POSS compound with more abundant and diversified types and performances can be obtained, and the POSS compound is expected to be applied to high-tech fields such as machinery, optics, electronics, aerospace and the like.

Detailed Description

The technical scheme of the invention is as follows:

a simple and efficient method for preparing T8-POSS comprises the following steps:

trialkoxysilane containing substituent groups is dissolved in an alcohol solvent, then weak base is added, then solvent A and catalyst are added, and then the mixture is transferred into a reaction kettle for solvothermal reaction, so that cage T8-POSS can be generated.

The synthetic technical route of the invention is as follows:

wherein: r' is phenyl or methyl.

According to the present invention, the alcohol solvent is an alcohol compound capable of dissolving the alkoxysilane, and methanol, ethanol, propanol, and n-butanol are preferable, and methanol and ethanol are more preferable.

According to the present invention, the weak base mentioned above means a weakly basic substance in a broad sense including inorganic bases and organic bases, preferably triethylamine, trimethylamine, diethylamine, dimethylamine, tetramethylethylenediamine, tetramethylpropylenediamine and tetramethylammonium hydroxide.

According to the present invention, the above-mentioned trialkoxysilane having a substituent is commercially available various trialkoxysilanes, preferably methyltriethoxysilane, methyltrimethoxysilane, chloropropyltrimethoxysilane, chloropropyltriethoxysilane, aminopropyltriethoxysilane, aminopropyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane and derivatives thereof having a substituent on the phenyl group, more preferably phenyltriethoxysilane, methyltriethoxysilane and aminopropyltriethoxysilane.

According to the present invention, it is preferred that the molar ratio of the substituent-containing trialkoxysilane, the weak base and the solvent is 1: (5-20): (10-100).

According to the present invention, the solvent a in the above solvothermal reaction is various solvents having a relatively high polarity and a mixture of various solvents, preferably toluene, anisole, tetrahydrofuran, acetonitrile, ethanol, methanol, chloroform, dichloromethane, N' -dimethylformamide and a mixture of the above solvents, and more preferably a mixture containing ethanol.

According to the invention, the catalyst for the above solvothermal reaction is a transition metal nitrate, preferably manganese nitrate, europium nitrate, zinc nitrate, copper nitrate or nickel nitrate.

According to the invention, the above-mentioned solvothermal reaction is carried out with a catalyst amount of 1-5 mol% based on the trialkoxysilane.

According to the invention, the reaction temperature of the solvothermal reaction is 70-200 ℃, preferably 110-140 ℃.

According to the invention, the reaction time of the abovementioned solvothermal reaction is from 10 to 48 hours, preferably from 20 to 40 hours.

The invention is not described in detail in the prior art.

The principle of the invention is as follows:

according to the invention, the POSS compound containing the T8 structure is prepared simply, in a short time and efficiently by skillfully designing the synthesis process and the reaction temperature and combining the optimization of a solvent. This provides a new approach to the preparation of highly pure POSS. The preparation method has the advantages of simple preparation process, high yield, unexpected effect and strong innovation compared with related literature reports.

The invention has the beneficial effects that:

1. the method for simply and efficiently preparing the T8-POSS has the characteristics of simple preparation process, easiness in industrial production, mild reaction conditions, no need of inert atmosphere, good controllability, unexpected effect and outstanding innovativeness.

2. The product T8-POSS prepared by the method has high yield which can reach 96%; the reaction efficiency is high, and the reaction can be completed within 10-48 hours.

3. The POSS compound with the cage structure can be directly used, and can also be obtained by modifying a functional group R' according to requirements, so that the multifunctional high-purity POSS compound with excellent performance is convenient to synthesize and has wide application prospect.

Drawings

FIG. 1 is a single crystal diffraction pattern of cage structure T8-POSS prepared in example 1 of the present invention.

Detailed Description

The present invention is further illustrated by, but is not limited to, the following specific examples.

The starting materials used in the examples are either conventional commercially available starting materials or are synthesized according to the literature methods.

Example 1

Firstly, 1 g of phenyltriethoxysilane is dissolved in 50 ml of ethanol, 0.2 g of triethylamine is added, then 10 mg of manganese nitrate and 30 ml of acetonitrile are added, the mixture is transferred to a reaction kettle for solvothermal reaction (the reaction temperature is 130 ℃, the reaction time is 30 hours), and after the experiment is finished, the reaction kettle is cooled to room temperature, so that the cage-type phenyl POSS containing the T8 structure can be obtained. The yield thereof was found to be 96%.

Example 2

Firstly, 1.5 g of phenyltrimethoxysilane is dissolved in 30 ml of propanol, 0.5 g of triethylamine is added, then 12 mg of europium nitrate and 30 ml of acetonitrile are added, the mixture is transferred into a reaction kettle for solvothermal reaction (the reaction temperature is 140 ℃, the reaction time is 25 hours), and after the experiment is finished, the reaction kettle is cooled to room temperature, so that the cage-type phenyl POSS containing the T8 structure can be obtained. The yield thereof was found to be 92%.

Example 3

Firstly, 1 g of phenyltriethoxysilane is dissolved in 30 ml of methanol, 0.5 g of triethylamine is added, then 20 mg of nickel nitrate and 40 ml of acetonitrile are added, the mixture is transferred to a reaction kettle for solvothermal reaction (the reaction temperature is 75 ℃, the reaction time is 30 hours), and after the experiment is finished, the reaction kettle is cooled to room temperature, so that the cage-type phenyl POSS containing the T8 structure can be obtained. The yield thereof was found to be 87%.

Example 4

Firstly, 2 g of phenyltrimethoxysilane is dissolved in 50 ml of alcohol, 0.8 g of tetramethylethylenediamine is added, then 20 mg of manganese nitrate and 30 ml of acetonitrile are added, the mixture is transferred into a reaction kettle to carry out solvothermal reaction (the reaction temperature is 100 ℃, the reaction time is 25 hours), and after the experiment is finished, the reaction kettle is cooled to room temperature, so that the cage-type phenyl POSS containing the T8 structure can be obtained. The yield thereof was found to be 92%.

Example 5

Firstly, 1 g of phenyltriethoxysilane is dissolved in 30 ml of methanol, 0.4 g of tetramethylethylenediamine is added, then 15 mg of copper nitrate and 20 ml of dichloromethane are added, the mixture is transferred to a reaction kettle for solvothermal reaction (the reaction temperature is 80 ℃, the reaction time is 30 hours), and after the experiment is finished, the reaction kettle is cooled to room temperature, so that the cage-type phenyl POSS containing the T8 structure can be obtained. The yield thereof was found to be 91%.

Test example 1

The cage-type POSS crystal prepared in the example 1 is subjected to single crystal diffraction characterization, as shown in FIG. 1, a structure test result shows that the cage-type POSS is successfully prepared, the reaction is relatively simple to operate and easy to control, the cage-type POSS is suitable for preparing cage-type POSS with different substituents, and compared with a synthesis method reported in literatures, the cage-type POSS has greater innovation and is expected to be applied to high-tech fields such as machinery, optics, electronics, aerospace and the like.

Claims

1. A simple and efficient method for preparing T8-POSS comprises the following steps:

2. The simple and efficient method for preparing T8-POSS as claimed in claim 1, wherein the alcoholic solvent is methanol, ethanol, propanol or n-butanol.

3. The simple and efficient method for preparing T8-POSS as claimed in claim 1, wherein the weak base is a broad weak base substance, and includes inorganic base and organic base;

triethylamine, trimethylamine, diethylamine, dimethylamine, tetramethylethylenediamine, tetramethylpropylenediamine and tetramethylammonium hydroxide are preferred.

4. The simple and efficient method for preparing T8-POSS according to claim 1, wherein the trialkoxysilane containing substituent is methyltriethoxysilane, methyltrimethoxysilane, chloropropyltrimethoxysilane, chloropropyltriethoxysilane, aminopropyltriethoxysilane, aminopropyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, or a derivative of trialkoxysilane containing substituent on phenyl.

5. The simple and efficient method for preparing T8-POSS according to claim 1, wherein the molar ratio of trialkoxysilane containing substituent, weak base and solvent is 1: (5-20): (10-100).

6. The simple and efficient method for preparing T8-POSS according to claim 1, wherein solvent A in the solvothermal reaction is toluene, anisole, tetrahydrofuran, acetonitrile, ethanol, methanol, chloroform, dichloromethane, N' -dimethylformamide or a mixture of the above solvents.

7. The simple and efficient method for preparing T8-POSS as claimed in claim 1, wherein the catalyst for the solvothermal reaction is transition metal nitrate;

manganese nitrate, europium nitrate, zinc nitrate, copper nitrate or nickel nitrate is preferred.

8. The simple and efficient method for preparing T8-POSS as claimed in claim 1, wherein the catalyst for solvothermal reaction is 1-5 mol% of trialkoxysilane.

9. The simple and efficient method for preparing T8-POSS according to claim 1, wherein the reaction temperature of the solvothermal reaction is 70-200 ℃, preferably 110-140 ℃.

10. The simple and efficient method for preparing T8-POSS as claimed in claim 1, wherein the reaction time of the solvothermal reaction is 10-48 hours, preferably 20-40 hours.