Water-soluble oligomeric silsesquioxane of olefins and method for producing the same

Abstract

This invention discloses a water-soluble olefin oligomeric silsesquioxane and its preparation method, wherein the structural formula of the water-soluble olefin oligomeric silsesquioxane is shown in Formula 1. Aminaminopropyltrialkoxysilane, an olefin-type haloalkane, an acid-binding agent, and toluene are mixed and reacted at 50℃-80℃ for 4-6 hours. The solid is separated, and the liquid is distilled to remove toluene and unreacted raw materials. The remaining liquid is the precursor of the olefin polyhedral oligomeric silsesquioxane. A catalyst and distilled water are added to the precursor, and the mixture is stirred and reacted at room temperature for 1-3 hours. The solvent water is recovered by vacuum distillation to obtain a crude product. The crude product is washed, filtered, and vacuum dried at room temperature to obtain the water-soluble olefin oligomeric silsesquioxane. The method of this invention has a simple synthesis process, using a sol-gel method to synthesize olefin functional group oligomeric silsesquioxanes in one step. The synthesis time is much shorter than that of traditional synthesis methods, and the obtained olefin oligomeric silsesquioxanes have good water solubility.

Description

Technical Field

[0001] This invention belongs to the field of polyhedral oligomeric silsesquioxane preparation technology, specifically, it relates to a novel water-soluble olefin oligomeric silsesquioxane and its preparation method. Background Technology

[0002] Polyhedral oligomeric silsesquioxanes (POSS) are compounds with a cage-like framework composed of inorganic Si-O and various organic groups surrounding it, with the general formula (RSiO). 3 / 2 The formula is n, where n = 6, 7, 8, 10, 12, etc. POSS is characterized by low density, high permeability, low dielectric constant, and excellent optical properties. Furthermore, POSS exhibits excellent thermal stability, radiation resistance, and oxidation resistance. The distance between the Si—O—Si bonds in the POSS molecule is only 0.5 nanometers, exhibiting surface and interface effects, small size effects, macroscopic quantum tunneling effects, and quantum size effects. These effects endow the POSS molecule with unique thermodynamic, optical, electrical, magnetic, and acoustic properties, thus attracting widespread attention.

[0003] Currently, the synthesis methods of POSS are mainly divided into two categories: one is the synthesis of POSS through the hydrolysis-condensation reaction of silanes or chlorosilanes, which is called the hydrolysis-condensation method; the other is the preparation of POSS by chemical reaction of side groups using existing POSS as the parent material, which is called the chemical derivatization method. In 1946, Scott (Scott DW. Thermal Rearrangement of Branched-Chain Methylpolysiloxanes. Journal of the American Chemical Society 1946;68(3):356-358.) first synthesized oligomeric silsesquioxanes. In 1955, Sprung (Sprung MM and Guenther FO. The Partial Hydrolysis of Methyltriethoxysilane. Journal of the American Chemical Society 1955; 77(15):3990-3996.) and others synthesized Me-POSS and analyzed its geometry. Subsequently, Barry (Barry AJ, Daudt WH, Domicone J, and Gilkey JW. Crystalline Organosilsesquioxanes. Journal of the American Chemical Society 1955; 77(16):4248-4252.) et al. synthesized T6 type Ph-POSS, T8 type Me-POSS, Ethyl-POSS, Propyl-POSS, Butyl-POSS, Cyclohexyl-POSS, and T12 type Me-POSS using strong base catalysts. They also synthesized several polymethylsilsesquioxanes with undetermined structures and characterized them. In 1963, Vogt (Vogt LH and Brown JF. Crystalline Methylsilsesquioxanes. Inorganic Chemistry 1963;2(1):189-192.) et al. used alkali as a catalyst to decompose methylsilyl gel and characterized it by mass spectrometry, nuclear magnetic resonance, infrared spectroscopy, etc., obtaining Me-POSS homologues (T8, T10, T12) and some polymethylsilsesquioxanes with undetermined structures. With the progress and development of science and technology, more and more POSS synthesis methods have been proposed, the types of synthesized POSS have continued to increase, and the yield has gradually improved.

[0004] In the 21st century, various POSSes with different organic groups have been successfully synthesized. These POSSes can be divided into two main categories: one is POSSes with inert groups, and the other is POSSes with active groups. POSSes with active groups can be further divided into two categories: one is POSSes with a single active group, and the other is POSSes with multiple active groups.

[0005] Olefin POSS belongs to the POSS category with active groups. Its double bonds can be introduced into materials through a series of chemical reactions, thereby improving the physicochemical properties of the materials. Currently, olefin POSS has been applied in multiple fields: its nanoscale structure and good surface activity make it an important material for preparing high-performance coatings, significantly improving the hardness and durability of coatings while exhibiting excellent corrosion resistance and optical properties; when combined with various polymer materials, it can significantly improve the mechanical properties, thermal stability, and optical properties of polymers, especially in enhancing the toughness and impact resistance of polymer matrices, where ethylene POSS demonstrates excellent performance; its good dielectric properties and heat resistance meet the high-performance requirements of electronic devices, making it suitable for use as an insulating material, electronic packaging material, and circuit board material; its excellent biocompatibility and bioactivity allow it to be used in the preparation of biomedical materials, such as artificial organs, drug carriers, and biosensors; in fields such as solar cells and fuel cells, ethylene POSS can serve as a functional material to improve energy conversion efficiency and device performance.

[0006] Currently, the literature reports that olefin-functionalized POSS is mainly ethylene olefin POSS, and its preparation methods include the following:

[0007] (Synthesis and characterization of vinyl-polyhedral oligomericsilsesquioxanes-reinforced silicone resin with three-dimensional cross-linking structure Inc. J. Appl. Polym. Sci. 2015, 132, 42187.): Ethylenetriethoxysilane and distilled water were stirred in anhydrous ethanol, and then an appropriate amount of hydrochloric acid was added and the reaction was carried out for 3 days. The product was washed with methanol to obtain a product yield of 20%.

[0008] (Synthesis and characterization of novel room temperature vulcanized (RTV) silicone rubbers using Vinyl-POSS derivatives as cross-linking agents. Polymer, 2010, 51, 17, 3867-3878): Acetone and ethylenetrimethoxysilane were added to a mixture of concentrated hydrochloric acid and deionized water, and the mixture was stirred and refluxed for 2 days. The mixture was centrifuged, washed with ethanol, and dried in a vacuum oven to obtain a crude product. The crude product was recrystallized from a mixed solvent of dichloromethane and acetone to obtain a product with a yield of 33.3%.

[0009] (Xue Yuhua, Gu Xueping, Feng Lianfang, Wang Jiajun, Hu Guohua. Synthesis and characterization of cage-like nanocompound octaethylene silsesquioxane. Journal of Zhejiang University (Engineering Science), 2007, 41(4), 679-682): 40 g of anhydrous ferric chloride was added to a 2 L round-bottom flask, followed by 25 mL of concentrated hydrochloric acid, 160 mL of methanol, 300 mL of petroleum ether, and 100 mL of dichloromethane, and the mixture was stirred continuously with a mechanical stirrer. 20 mL of ethylene trichlorosilane was dissolved in petroleum ether to prepare a 200 mL petroleum ether solution, which was then added dropwise to the reactor over 9 h using a constant-pressure dropping funnel. After stirring for 48 h to allow the reaction to proceed fully, the mixture was filtered and separated. The upper organic layer was transferred to a 1 L round-bottom flask, and 10 g of sodium carbonate and 10 g of calcium chloride were added. The mixture was stirred for 12 h and then filtered. The filtrate was evaporated to approximately 10 mL, and 4.2 g of crystals precipitated from the mother liquor, with a yield of 34.7%. The structural formula of the product is as follows:

[0010]

[0011] The methods described above all involve the hydrolytic polymerization of ethylene-trialkoxysilanes catalyzed in non-aqueous or aqueous solutions to prepare ethylene POSS. These methods are complex, time-consuming, and have low yields, resulting in high product costs. Furthermore, the obtained products have low polarity and are almost insoluble in polar solvents (such as water), making them unsuitable for polar systems. Summary of the Invention

[0012] The purpose of this invention is to provide a water-soluble olefin oligomeric silsesquioxane and its preparation method, so as to solve the problems of complex process, long synthesis cycle, high product cost and poor water solubility of olefin oligomeric silsesquioxane in the prior art.

[0013] To achieve the above objectives, according to one aspect of the present invention, a water-soluble olefin oligomeric silsesquioxane is provided, the structural formula of which is shown in Formula 1:

[0014]

[0015] in, X=HCOO - NO3 - or CF3SO3 - CH3COO - n = 1, 2, 3.

[0016] According to another aspect of the present invention, a method for preparing the above-described water-soluble olefin oligomeric silsesquioxane is provided, which first synthesizes an olefin functional group POSS precursor, and then synthesizes a water-soluble olefin functional group POSS with a novel structure using a sol-gel method, comprising the following steps:

[0017] Step 1: Prepare the olefin polyhedral oligomeric silsesquioxane precursor as shown in Formula 2: Mix aminopropyltrialkoxysilane, olefin-type haloalkanes, acid-binding agents and toluene, react at 50℃-80℃ for 4-6 hours, separate the solid, distill off the toluene and unreacted raw materials from the liquid, and the remaining liquid is the olefin polyhedral oligomeric silsesquioxane precursor.

[0018]

[0019] Where R is an alkyl chain; n = 1, 2, 3.

[0020] Step 2: Add catalyst and distilled water to the olefin polyhedral oligomeric silsesquioxane precursor obtained in Step 1, and stir the reaction at room temperature for 1-3 hours.

[0021] Step 3: Reduced pressure distillation is used to recover the solvent water, yielding the crude product;

[0022] Step four: At room temperature, acetone is added to the crude product for washing and filtration, followed by vacuum drying to obtain the water-soluble olefin oligomeric silsesquioxane.

[0023] In the above preparation method, toluene mentioned in step one is used as a solvent. The olefinic haloalkane reacts with aminopropyltrialkoxysilane to generate a precursor. The role of the acid-binding agent is to neutralize the hydrogen chloride generated in the reaction. The molar ratio of aminopropyltrialkoxysilane, olefinic haloalkane, and acid-binding agent is 1:1:1.

[0024] Furthermore, in step one, the aminopropyltrialkoxysilane is selected from aminopropyltrimethoxysilane, aminopropyltriethoxysilane, or aminopropyltripropoxysilane.

[0025] Furthermore, in step one, the acid-binding agent is selected from triethylamine, potassium carbonate, or sodium carbonate.

[0026] Furthermore, in step one, the olefinic haloalkane is selected from iodoolefins, bromoolefins, or chlorinated olefins.

[0027] Furthermore, in step two, the catalyst is selected from one or more combinations of hydrochloric acid, trifluoromethanesulfonic acid, fluorosulfuric acid, sulfuric acid, p-toluenesulfonic acid, formic acid, acetic acid, etc.

[0028] Furthermore, in step two, the molar ratio of the acid catalyst to the precursor is (1.1~1.8):1.0.

[0029] Furthermore, in step two, the molar ratio of the acid catalyst to the precursor is 1.5:1.0.

[0030] Furthermore, in step three, the heating temperature is 60-120℃.

[0031] Furthermore, in step three, the heating temperature is 70°C.

[0032] The principle behind the synthesis of olefin functional group POSS using the method of this invention is based on the ease with which protons separate from mixed acids. The amino group of the starting material readily undergoes protonation with the mixed acid in water, generating ammonium ions. When the solvent is heated and evaporated, the starting material condenses under the electrostatic repulsion between these ammonium ions, thus forming a compound with a large distance between the side chain groups, i.e., POSS. Since the side chain groups carry acid radical ions, which are negatively charged ions, these ions form electrostatic interactions in water, interacting with the positively charged hydrogen atoms in water molecules. This makes the olefin oligomeric silsesquioxane provided by this invention water-soluble.

[0033] The method of this invention is simple to synthesize, using a sol-gel method to synthesize olefin-functionalized oligomeric silsesquioxanes in one step. This method is more efficient in preparing olefin-functionalized POSS, with a synthesis time significantly shorter than traditional methods, and the obtained olefin-functionalized oligomeric silsesquioxanes exhibit good water solubility.

[0034] Furthermore, the use of vinyl POSS provided by this invention to modify PMMA resin and silicone resin significantly improves their thermal stability, scratch resistance, tensile strength, and light transmittance. Attached Figure Description

[0035] Figure 1 X-ray diffraction (XRD) of the olefin functional group POSS obtained in Example 1 of the present invention;

[0036] Figure 2 Fourier transform infrared (FT-IR) spectrum of olefin functional group POSS obtained in Example 1 of this invention;

[0037] Figure 3The proton nuclear magnetic resonance spectrum of the olefin functional group POSS obtained in Example 1 of this invention ( 1 H NMR);

[0038] Figure 4 The carbon nuclear magnetic resonance spectrum of the olefin functional group POSS obtained in Example 1 of this invention ( 13 (C NMR);

[0039] Figure 5 This is a comparison diagram of the water solubility of the product obtained in Example 1 and the product obtained in Comparative Example 1 of the present invention, wherein... Figure 5 (A) is a solubility diagram of the product in aqueous solution in Comparative Example 1. Figure 5 (B) is a diagram showing the solubility of the product in aqueous solution in Example 1. Detailed Implementation

[0040] The technical solutions claimed in this invention will be further described below through some embodiments. However, the embodiments and comparative examples are for explaining the implementation schemes of this invention and do not exceed the scope of the subject matter of this invention. The scope of protection of this invention is not limited by the embodiments. Unless otherwise specified, the materials and reagents used in this invention can be obtained from commercially available products in the art. Example 1

[0041] In a single-necked flask, 18.0 g of aminopropyltrimethoxysilane, 8.0 g of triethylamine, and 90.0 g of toluene were mixed. 12.0 g of allyl chloride was added, and the mixture was reacted at 50 °C for 5.0 h. The precipitate was filtered, and the solvent was evaporated to obtain 20.0 g of an olefin polyhedral oligomeric silsesquioxane precursor (yield 76.8%). 2.0 g of the olefin polyhedral oligomeric silsesquioxane precursor was taken, and 1.0 g of hydrochloric acid, 2.0 g of trifluoromethanesulfonic acid, and 60.0 g of water were added. The resulting solution was stirred and reacted at room temperature for 2.0 h. The solvent was completely evaporated to obtain a crude product. 5.0 ml of acetone was added at room temperature for washing and filtration, and the product was dried under vacuum for 1.0 h to obtain 2.0 g of the product (yield 91.4%). Example 2

[0042] A single-necked flask was filled with a mixture of 36.0 g of aminopropyltriethoxysilane, 15.0 g of potassium carbonate, and 150.0 g of toluene. 25.0 g of bromopropylene was added, and the mixture was reacted at 60 °C for 4.0 h. The precipitate was filtered off, and the solvent was evaporated to obtain 38.0 g of an olefin polyhedral oligomeric silsesquioxane precursor (yield 78.2%). 5.0 g of the olefin polyhedral oligomeric silsesquioxane precursor was added, along with 1.0 g of p-toluenesulfonic acid, 4.0 g of trifluoromethanesulfonic acid, and 100.0 g of water. The resulting solution was stirred at room temperature for 2.50 h. The solvent was completely evaporated to obtain a crude product, which was washed and filtered with 8.0 ml of acetone at room temperature. The product was then vacuum dried for 1.5 h to obtain 4.50 g of the product (yield 85.6%). Example 3

[0043] Take a single-necked flask and add 15.0 g of aminopropyltripropoxysilane, 6.0 g of sodium carbonate, and 80.0 g of toluene; add 10.0 g of iodopropylene and react at 70 °C for 3.0 h; filter to precipitate and evaporate the solvent to obtain 18.0 g of olefin polyhedral oligomeric silsesquioxane precursor (yield 86.7%). Take 15.0 g of olefin polyhedral oligomeric silsesquioxane precursor; add 3.0 g of p-toluenesulfonic acid, 2.0 g of trifluoromethanesulfonic acid, 10.0 g of formic acid, and 300.0 g of water; stir the resulting solution at room temperature for 3.0 h. Evaporate the solvent completely to obtain the crude product, wash and filter with 20.0 ml of acetone at room temperature, and vacuum dry for 2.0 h to obtain 10.0 g of product (yield 87.8%). Example 4

[0044] A single-necked flask was filled with a mixture of 20.0 g of aminopropyltriethoxysilane, 13.0 g of triethylamine, and 120.0 g of toluene. 35.0 g of vinyl iodide was added, and the mixture was reacted at 80 °C for 2.0 h. The precipitate was filtered off, and the solvent was evaporated to obtain 25.0 g of an olefin polyhedral oligomeric silsesquioxane precursor (yield 82.3%). 20.0 g of the olefin polyhedral oligomeric silsesquioxane precursor was then mixed with 5.0 g of fluorosulfuric acid, 20.0 g of acetic acid, and 400.0 g of water. The resulting solution was stirred and reacted at room temperature for 2.0 h. The solvent was completely evaporated to obtain a crude product, which was washed and filtered with 25.0 ml of acetone at room temperature. The product was then dried under vacuum for 1.0 h to obtain 12.0 g of the product (yield 84.6%). Example 5

[0045] A single-necked flask was filled with a mixture of 25.0 g of aminopropyltrimethoxysilane, 12.0 g of sodium carbonate, and 180.0 g of toluene. 38.0 g of chloroprene was added, and the mixture was reacted at 50 °C for 6.0 h. The precipitate was filtered off, and the solvent was evaporated to obtain 30.0 g of an olefin polyhedral oligomeric silsesquioxane precursor (yield 83.4%). 25.0 g of the olefin polyhedral oligomeric silsesquioxane precursor was then added to a mixture of 5.0 g of p-toluenesulfonic acid, 30.0 g of formic acid, and 380.0 g of water. The resulting solution was stirred and reacted at room temperature for 2.50 h. The solvent was completely evaporated to obtain the crude product, which was washed and filtered with 30.0 ml of acetone at room temperature. The product was then vacuum dried for 1.5 h to obtain 16.0 g of the product (yield 83.6%). Example 6

[0046] A single-necked flask was filled with a mixture of 22.0 g of aminopropyltripropoxysilane, 10.0 g of potassium carbonate, and 160.0 g of toluene. 45.0 g of vinyl chloride was added, and the mixture was reacted at 50 °C for 5.5 h. The precipitate was filtered off, and the solvent was evaporated to obtain 28.0 g of an olefin polyhedral oligomeric silsesquioxane precursor (yield 84.6%). 22.0 g of the olefin polyhedral oligomeric silsesquioxane precursor was then mixed with 5.0 g of fluorosulfuric acid, 25.0 g of sulfuric acid, and 350.0 g of water. The resulting solution was stirred and reacted at room temperature for 3.0 h. The solvent was completely evaporated to obtain the crude product, which was washed and filtered with 25.0 ml of acetone at room temperature. The product was then vacuum dried for 1.0 h to obtain 25.0 g of the product (yield 87.5%). Example 7

[0047] A single-necked flask was filled with a mixture of 25.0 g of aminopropyltriethoxysilane, 13.0 g of triethylamine, and 180.0 g of toluene. 28.0 g of chloroprene was added, and the mixture was reacted at 50 °C for 4.0 h. The precipitate was filtered off, and the solvent was evaporated to obtain 26.50 g of an olefin polyhedral oligomeric silsesquioxane precursor (yield 81.7%). 25.0 g of the olefin polyhedral oligomeric silsesquioxane precursor was then added to a mixture of 5.0 g of p-toluenesulfonic acid, 30.0 g of acetic acid, and 370.0 g of water. The resulting solution was stirred at room temperature for 2.0 h. The solvent was completely evaporated to obtain a crude product, which was washed and filtered with 23.0 ml of acetone at room temperature. The product was then vacuum dried for 1.5 h to obtain 18.0 g of the product (yield 86.2%). Example 8

[0048] A single-necked flask was filled with a mixture of 32.0 g of aminopropyltrimethoxysilane, 18.0 g of potassium carbonate, and 160.0 g of toluene. 18.0 g of bromobutene was added, and the mixture was reacted at 50 °C for 6.0 h. The precipitate was filtered off, and the solvent was evaporated to obtain 32.0 g of an olefin polyhedral oligomeric silsesquioxane precursor (yield 82.5%). 27.50 g of the olefin polyhedral oligomeric silsesquioxane precursor was then added to 1.0 g of p-toluenesulfonic acid, 4.0 g of fluorosulfuric acid, and 420.0 g of water. The resulting solution was stirred at room temperature for 3.50 h. The solvent was completely evaporated to obtain the crude product, which was washed and filtered with 35.0 ml of acetone at room temperature. The product was then dried under vacuum for 2.0 h to obtain 14.50 g of the product (yield 81.6%).

[0049] Comparative Example 1

[0050] Ethylenetriethoxysilane (50 mL) and distilled water (18 mL) were dissolved in anhydrous ethanol (80 mL) and stirred. Then, an appropriate amount of hydrochloric acid was added and the reaction was carried out for 3 days. The product was washed with methanol to obtain a product yield of 20.0%.

[0051] The olefin functional groups POSS described in Comparative Example 1 are shown in Formula 3.

[0052]

[0053] The structural formula for R is: .

[0054] Compared to Example 1, the synthesis time (8 hours) of the olefin functional group POSS prepared in Example 1 was 1 / 12 of that in Comparative Example 1. The reaction yield in Comparative Example 1 was 91.4%, while the reaction yield in Example 1 was 20.0%. Furthermore, the product obtained in Example 1 was soluble in aqueous solution. This indicates that the olefin functional group POSS prepared by this method is more efficient, and because the product is soluble in aqueous solution, its applications are more widespread.

[0055] Application Example 1

[0056] The olefin POSS obtained in Example 1 was mixed with PMMA resin at a mass ratio of 1:4. 2.5 g of olefin POSS and 10.0 g of PMMA resin were weighed and added to an Erlenmeyer flask. Approximately 0.0375 g (0.3% of the total mass of olefin POSS and PMMA resin) of the free radical initiator AIBN (azobisisobutyronitrile) and 0.1 g of the plasticizer dioctyl phthalate (1% of PMMA) were added and stirred until homogeneous. The mixture was then heated at 80°C for 30 min until the viscosity of the system reached approximately 100 mPa·s. After cooling to room temperature, the resulting viscous liquid product was poured into a container with a volume (length × width × depth) of 10 × 10 × 0.4 cm. 3 The mixture is sealed in a polytetrafluoroethylene mold, then heated at 60°C for 6 hours, and then heated to 100°C for 1 hour. After the reaction is complete, it is cooled to room temperature, and the resulting transparent solid sample is the olefin POSS modified PMMA resin.

[0057] Table 1. Results of performance testing of olefin POSS-modified PMMA resin

[0058]

[0059] As shown in Table 1, the weight loss temperature of PMMA resin without this product is 90.6℃, while that with this product is 120.8℃, indicating that olefin POSS has a good enhancing effect on the thermal stability of silicone resin. The scratch resistance of silicone resin without this product is grade 1, while that with this product is grade 4, indicating that olefin POSS enhances the abrasion resistance of silicone resin. The vinyl POSS-modified PMMA resin of this invention not only has good thermal stability and scratch resistance, but is also colorless and transparent with a light transmittance as high as 98.0%, and has a higher elongation at break than the unmodified version, and its pencil hardness is also significantly improved.

[0060] Application Example 2

[0061] In a three-necked reaction flask equipped with a reflux condenser, a mechanical stirrer, and a constant-pressure dropping funnel, 0.5 g of ethylene POSS, 100 g of hydrogen-containing silicone oil (0.5% hydrogen content), and 100 g of toluene obtained in Example 1 were added and stirred until homogeneous. Under nitrogen protection, 0.0002 g of Karl Fischer catalyst (1,3-diethylene-1,1,3,3-tetramethyldisiloxane platinum(O)) was added, and the mixture was heated to reflux for 1 hour. The mixture was then rotary evaporated to obtain the POSS-grafted modified polysiloxane polymer. Preparation of the encapsulant: 100 g of the POSS-grafted modified polysiloxane polymer and 75 g of ethylene silicone oil were mixed evenly, and 0.0009 g of Karl Fischer catalyst was added. After stirring evenly, the mixture was poured into a preheated mold, air bubbles were removed, and the mixture was left to stand for 24 hours. Then, it was cured according to a curing process of 80℃ / 1 hour and 150℃ / 2 hours. After cooling and demolding, the ethylene POSS-modified silicone resin encapsulant was obtained.

[0062] Table 2 Performance Indicators of Olefin POSS Modified Silicone Resin Encapsulant

[0063]

[0064] As shown in Table 2, the 5% weight loss temperature of the silicone resin encapsulant without this product is 302℃, while the 5% weight loss temperature with this product is 323℃, indicating that olefin POSS has a good enhancing effect on the thermal stability of the silicone resin encapsulant. The tensile strength of the silicone resin encapsulant without this product is 2.875 MPa, while the tensile strength of the silicone resin encapsulant with this product is 3.519 MPa, indicating that olefin POSS has an enhancing effect on the tensile strength of the silicone resin encapsulant. The silicone resin modified with vinyl POSS of this invention not only has good thermal stability and tensile strength, but also produces an encapsulant with excellent optical properties, being colorless and transparent, with a refractive index as high as 1.44 and a light transmittance as high as 95%, which can be widely used in LED encapsulation materials, coating materials, and optical lens materials.

Claims

1. A water-soluble olefin oligomeric silsesquioxane, characterized in that, Its structural formula is shown in Equation 1: ； in, X=HCOO - CF3SO3 - or CH3COO - n = 1, 2, 3.

2. A method for preparing the water-soluble olefin oligomeric silsesquioxane as described in claim 1, characterized in that, Includes the following steps: Step 1: Prepare the olefin polyhedral oligomeric silsesquioxane precursor as shown in Formula 2; mix aminopropyltrialkoxysilane, olefin-type haloalkanes, acid-binding agents and toluene, react at 50℃-80℃ for 4-6 hours, separate the solid, distill off the toluene and unreacted raw materials from the liquid, and the remaining liquid is the olefin polyhedral oligomeric silsesquioxane precursor. ； Wherein, n=1, 2, 3; the aminopropyltrialkoxysilane is selected from aminopropyltrimethoxysilane, aminopropyltriethoxysilane, or aminopropyltripropoxysilane; Step 2: Add catalyst and distilled water to the olefin polyhedral oligomeric silsesquioxane precursor obtained in Step 1, and stir the reaction at room temperature for 1-3 hours. Step 3: Reduced pressure distillation is used to recover the solvent water, yielding the crude product; Step four: At room temperature, acetone is added to the crude product for washing and filtration, followed by vacuum drying to obtain the water-soluble olefin oligomeric silsesquioxane.

3. The method according to claim 2, characterized in that: In step one, the acid-binding agent is selected from triethylamine, potassium carbonate, or sodium carbonate.

4. The method according to claim 3, characterized in that: In step one, the olefinic haloalkane is selected from iodoolefins, bromoolefins, or chlorinated olefins.

5. The method according to claim 2 or 4, characterized in that: In step two, the catalyst is selected from one or more combinations of hydrochloric acid, trifluoromethanesulfonic acid, fluorosulfuric acid, sulfuric acid, p-toluenesulfonic acid, formic acid, and acetic acid.

6. The method according to claim 5, characterized in that: In step two, the molar ratio of the catalyst to the precursor is (1.1~1.8):1.

0.

7. The method according to claim 6, characterized in that: In step two, the molar ratio of the catalyst to the precursor is 1.5:1.0.

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