Transparent photocurable sulfydryl aryl silicone oil with high refractive index as well as preparation and application of transparent photocurable sulfydryl aryl silicone oil

Abstract

The invention belongs to the technical field of organic silicon materials, and particularly relates to high-refractive-index transparent light-curable sulfydryl aryl silicone oil as well as preparation and application of the high-refractive-index transparent light-curable sulfydryl aryl silicone oil. The high-refractive-index transparent light-curable sulfydryl aryl silicone oil is prepared through a hydrolytic polycondensation method, contains aryl groups and light-curable sulfydryl groups, can achieve the characteristics of high refractive index, high light transmittance, good stability and the like, can be rapidly cured through sulfydryl-alkene photopolymerization under ultraviolet light, and is suitable in mechanical strength, transparent in appearance and high in transparency after being cured. The material can be applied to the fields such as aerospace, electronic and electric appliances, high-temperature sealing and the like which need to bear high temperature or have strict requirements on environmental pollution, particularly has wide application prospects in the fields such as optical materials, optoelectronic devices and 3D printing, and has remarkable advantages and market potential.

Description

Technical Field

[0001] The present invention belongs to the technical field of silicone materials, and particularly relates to a high refractive index transparent photocurable mercaptoaryl silicone oil and its preparation and application. Background Art

[0002] Currently, the vulcanization molding process of silicone polymers mainly relies on room temperature and high temperature vulcanization methods. Both of these methods require a long curing process, which not only takes a long time and is difficult to achieve continuous production, but also the high temperature vulcanization process needs to be carried out in a high temperature environment of 150 to 180 degrees Celsius. This not only limits its co-molding application with heat-sensitive components, but also causes problems such as insufficient environmental protection due to high energy consumption for a long time. In addition, whether it is room temperature or high temperature vulcanized silicone rubber, its vulcanization process lacks precise control in terms of time and space. In contrast, ultraviolet curing technology, as a fast, efficient, energy-saving and environmentally friendly green process, its energy consumption is only about one-tenth of that of thermal curing, and it can quickly complete the curing and molding within a few seconds. However, due to the limitations of photosensitive silicone raw materials on the market, existing silicone polymers are difficult to directly achieve rapid ultraviolet curing. In order to overcome this problem, it is necessary to carry out photosensitization modification on the polysiloxane chain. However, in this process, due to the polar characteristics of the photocuring group, it is easy to cause gelation and difficulty in achieving transparency during the preparation process, which not only limits the photocuring rate but also increases the difficulty of preparation.

[0003] "Click chemistry" is a new chemical reaction strategy, and its core lies in using the special reactivity of mercapto groups (i.e., -SH functional groups) to undergo rapid and selective addition reactions with molecules such as alkenes and alkynes. This reaction method is not only efficient and can be carried out under mild conditions, but also has high selectivity, ensuring high purity and controllability of the product. In the field of polymer synthesis, mercapto "click chemistry" can prepare sequence-regular polymers with excellent properties by precisely controlling chain growth and crosslinking, providing a new way for the development of functional materials. In addition, this technology also has extensive applications in material modification, and can endow materials with new or enhanced properties, such as wear resistance, corrosion resistance and biocompatibility, through chemical modification of the material surface. In the field of biological applications, mercapto "click chemistry" has shown great potential, and can not only be used for the preparation of biomolecules such as gene delivery and photothermal therapy, but also provide strong support for the development of new drug research and development and nanotechnology. It is one of the most effective methods for the photosensitization of current silicone materials.

[0004] Mercapto silicone oil, as a completely synthetic new type of organosilicon polymer lubricant, exhibits multiple excellent properties: First of all, it has excellent lubrication performance, can significantly reduce friction and improve the demolding effect; at the same time, it has excellent rust and corrosion prevention performance, can remain stable in high-temperature environments, and has good waterproof and anti-sticking properties; particularly, the photocuring characteristics of mercapto silicone oil enable it to be used to prepare a variety of rapidly cured photocuring products, such as semiconductor coatings and optical fiber coatings; in addition, it is widely used in multiple fields such as semiconductor manufacturing, optical fiber manufacturing, paper and plastic film manufacturing, and as a green and environmentally friendly product, it is pollution-free to the environment and harmless to the human body, meeting environmental protection and safety requirements.

[0005] With the rapid development of modern optics, optoelectronics and information technology, etc., products are also constantly being studied towards the directions of high transparency, high refractive index, high light transmittance and high reliability. The research directions include LED packaging materials, gradient refractive index materials, nonlinear optical materials, environmentally friendly optical materials, liquid crystal materials and optical wave materials, etc. These materials have certain requirements for the refractive index, and generally, the higher the refractive index, the better the performance. Organosilicon polymers, due to their environmental friendliness, non-toxicity, excellent mechanical properties, high and low temperature resistance, elasticity and physiological inertness, etc., have wide application values in fields such as optical lenses, optical coatings, optical adhesives, optical glass, optical fibers, optical plastics and flexible displays. However, this requires that the organosilicon polymer can maintain high transparency and mechanical strength while having a higher refractive index. Usually, the main way to increase the refractive index of organosilicon polymers is to introduce high refractive index groups on the polysiloxane molecular chain:

[0006] (1) Introducing polycyclic and aromatic groups can effectively increase the refractive index of organosilicon polymers, but introducing too many will cause large dispersion, and the mechanical properties will be hard and brittle, affecting the use. Within the allowable range of mechanical properties, by introducing benzene rings, the refractive index of organosilicon polymers can generally only reach about 1.54;

[0007] (2) Introducing halogen atoms (except fluorine atoms) can effectively increase the refractive index, but there are still problems such as high density, poor weather resistance and easy yellowing;

[0008] (3) Introducing heavy metal ions (such as lead, lanthanum or TiO 2 , PbS, FeS nanoparticles) can increase the refractive index, but there are problems such as high density, low impact resistance, easy yellowing and difficulty in practical use;

[0009] (4) Introducing aliphatic polycyclic groups can increase the refractive index, but there are also problems such as low dispersion and low mechanical properties;

[0010] (5) Introducing groups containing elements such as N, P, S, etc. can also increase the refractive index.

[0011] Moreover, in the prior art, there are generally defects such as long thermal curing time, time-consuming and energy-consuming of silicone polymers, and generally low refractive index. Summary of the Invention

[0012] To solve the above problems, the present invention provides a highly refractive transparent photocurable mercaptoaryl silicone oil. The highly refractive transparent photocurable mercaptoaryl silicone oil is prepared by a hydrolysis polycondensation method and contains aryl groups and photocurable mercapto groups, which can achieve characteristics such as high refractive index, high light transmittance, and good stability. At the same time, it can be rapidly cured by thiol-ene photopolymerization under ultraviolet light, and the thioether structure contained in the prepared silicone material can endow it with excellent toughness, refractive index, heat resistance, hydrolysis resistance, adhesion, and antioxidant properties, etc.

[0013] The present invention also provides the uses of the above highly refractive transparent photocurable mercaptoaryl silicone oil and the silicone material prepared therefrom, which can be widely applied in the fields of UV-LED packaging, optical materials, optoelectronic devices, optical coatings, optical lenses, optical adhesive sealants, optical fiber coatings, communication, and information processing, etc.

[0014] The present invention will achieve the above objectives through the following technical solutions:

[0015] The present invention provides a highly refractive transparent photocurable mercaptoaryl silicone oil, which conforms to the following general formula:

[0016] (R 1 R 2 R 3 SiO 1 / 2 ) a (R 4 R 5 SiO 2 / 2 ) b (R 6 R 7 SiO 2 / 2 ) c (R 8 R 9 SiO 2 / 2 ) d ;

[0017] Among them, R 1 , R 2 and / or R 3 is a hydrogen atom or a hydrocarbon group without aliphatic unsaturated bonds;

[0018] Among them, R 4 is an aromatic hydrocarbon group; R 5 is an aromatic hydrocarbon group or a hydrocarbon group without aliphatic unsaturated bonds;

[0019] Among them, R 6is a monovalent hydrocarbon group containing a mercapto group and no aliphatic unsaturated bond; R 7 is methoxy or methyl;

[0020] wherein, R 8 and / or R 9 is an alkyl group;

[0021] wherein, 1 > a, b, c and d > 0.

[0022] The high refractive index transparent photocurable mercapto aryl silicone oil of the present invention contains both aryl groups and photocurable mercapto groups, and can rapidly prepare silicone products.

[0023] Specifically, the monovalent hydrocarbon group without aliphatic unsaturated bond includes but is not limited to methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl or similar alkyl groups; aromatic hydrocarbon groups include but are not limited to phenyl, naphthalene, tolyl, xylyl or similar aryl groups, benzyl, phenethyl, phenylpropyl or similar aralkyl groups; the monovalent hydrocarbon group containing a mercapto group and no aliphatic unsaturated bond includes but is not limited to mercaptopropyl or mercapto; alkyl groups include but are not limited to methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl or similar alkyl groups, preferably methyl.

[0024] Further, in the general formula, a, b, c and d satisfy: 1 ≤ (b + c) / d ≤ 8 and a + b + c + d = 1 and 0.2 ≤ b ≤ 0.5 and 0.1 ≤ c ≤ 0.3 and 0 ≤ d ≤ 0.4.

[0025] Further, in the general formula, R 1 、R 2 and R 3 are methyl.

[0026] Further, in the high refractive index transparent photocurable mercapto aryl silicone oil, the mercapto content is 0.10 - 0.50 mol / 100 g; the aryl content is 0.30 - 0.90 mol / 100 g.

[0027] Further, the high refractive index transparent photocurable mercapto aryl silicone oil has a kinematic viscosity of 800 - 40000 mPa·s at 25°C, a refractive index of 1.46 - 1.70 at 25°C, and a light transmittance of ≥ 85% at 450 nm.

[0028] The present invention also provides a preparation method of the above-mentioned high refractive index transparent photocurable mercapto aryl silicone oil, which is characterized by including the following steps: reacting a silane monomer containing a hydrolyzable group, a capping agent and deionized water by hydrolysis polycondensation under the promotion of an acid, a base, a salt or a metal oxide to obtain the high refractive index transparent photocurable mercapto phenyl silicone oil.

[0029] Further, the silane monomer containing a hydrolyzable group includes a mercapto silane monomer and an aryl silane monomer; the hydrolyzable group includes, but is not limited to, halogen, alkoxy or acyloxy.

[0030] Specifically, the capping agent is a commonly used capping agent in silicone polymerization, such as a hydrocarbyl silane capping agent, a vinyl silane capping agent or a hydrogen silane capping agent; the hydrocarbyl silane capping agent includes, but is not limited to, hexamethyldisiloxane ([(CH 3 ) 3 Si] 2 O), trimethylmethoxysilane ((CH 3 ) 3 SiOCH 3 ), trimethylethoxysilane ((CH 3 ) 3 SiOC 2 H 5 ), hexamethyldisilazane ([(CH 3 ) 3 Si] 2 NH), hexaphenyldisiloxane ([(C 6 H 5 ) 3 Si] 2 O); the hydrogen silane capping agent includes, but is not limited to, dimethylsiloxydimethylsilane (HMe 2 SiOSiMe 2 H), dimethylsilazodimethylsilane (HMe 2 SiNSiMe 2 H), dimethylethoxysilane (HMe 2 SiOEt).

[0031] Specifically, acids, bases, salts or metal oxides can be added to promote the hydrolysis reaction, and one or more of concentrated sulfuric acid (98% mass fraction), concentrated hydrochloric acid (37% mass fraction), trifluoromethanesulfonic acid or strongly acidic cation exchange resin can be selected.

[0032] Specifically, it also includes an alkali removal and purification step, and the water washing method (the washing liquid is a saturated ethanol solution of sodium carbonate or sodium bicarbonate, and after washing, it needs to be layered, and the organic phase is dried with a desiccant, rotary evaporated and vacuum concentrated to obtain the product) or the direct method (anhydrous sodium carbonate, anhydrous ammonium bicarbonate or anhydrous sodium bicarbonate is directly added, preferably anhydrous sodium carbonate, and the product is obtained after rotary evaporation and filtration) can be used, and the direct method is preferred.

[0033] Specifically, the reaction temperature of the hydrolysis and polycondensation reaction is 60 - 80 °C, and the time is 3 - 5 h.

[0034] Specifically, the addition amounts of the mercapto-silane monomer and the aryl-silane monomer do not exceed 80% of the sum of the masses of the silane monomers containing hydrolyzable groups; the addition amount of the photoinitiator is 0.1%-1% of the sum of the masses of the silane monomers containing hydrolyzable groups.

[0035] Specifically, the molar addition amount of deionized water is 2-4 times the sum of the molar amounts of the silane monomers containing hydrolyzable groups. Adding water dropwise can hydrolyze the alkoxysilane into a silanol compound, thus facilitating the subsequent polycondensation reaction.

[0036] The present invention also provides an organosilicon material prepared from the above high refractive index transparent photocurable mercapto-aryl silicone oil.

[0037] The present invention also provides a preparation method of the above organosilicon material, which includes the following steps: uniformly stirring the high refractive index transparent photocurable mercapto-aryl silicone oil, the terminal vinyl silicone oil, the anchoring agent and the photoinitiator, and carrying out thiol-ene photo-click chemistry under ultraviolet light irradiation for crosslinking and curing to obtain the organosilicon material.

[0038] Specifically, the photoinitiator can be a radical photoinitiator, such as benzoin and its derivatives, benzil and its derivatives, α-hydroxyalkyl phenyl ketones, α-aminoalkyl phenyl ketones, acylphosphine oxides, benzophenones, and heterocyclic aromatic ketones, etc.; including but not limited to 2-hydroxy-2-methylpropiophenone (Darocure 1173), 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO), ethyl 2,4,6-trimethylbenzoyl phenylphosphinate (TPO-L), 2-hydroxy-4-(2-hydroxyethoxy)-2-methylpropiophenone (Darocure 2959), 1-hydroxycyclohexyl phenyl ketone (Irgacure 184), 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropanone (Irgacure 907), 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone (Irgacure 369), phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (Irgacure 819), 1,1'-(methylenedi-4,1-phenylene)bis[2-hydroxy-2-methyl-1-propanone] (Irgacure 127), benzophenone (BP), 2,4,6-trimethylbenzophenone, tetraethyl Michler's ketone (DEMK), isopropylthioxanthone (ITX), 1-chloro-4-propoxythioxanthone (CPTX), and photoinitiator EDAB (1101), etc. Preferably, it is one or more of 2-hydroxy-2-methylpropiophenone (Darocure 1173), 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO), ethyl 2,4,6-trimethylbenzoyl phenylphosphinate (TPO-L), 2-hydroxy-4-(2-hydroxyethoxy)-2-methylpropiophenone (Darocure 2959), 1-hydroxycyclohexyl phenyl ketone (Irgacure 184).

[0039] Specifically, the ultraviolet light uses a mercury lamp source of 200 - 400 nm, and the maximum irradiation intensity is 70 - 150 mW / cm 2 , and the irradiation time is 5 - 15 min.

[0040] Specifically, the end-capping agent is a commonly used end-capping agent in silicone polymerization, such as a hydrocarbyl silane end-capping agent, a vinyl silane end-capping agent, or a hydrogen silane end-capping agent; the hydrocarbyl silane end-capping agent includes but not limited to hexamethyldisiloxane ([(CH 3 ) 3 Si] 2 O), trimethylmethoxysilane ((CH 3 ) 3 SiOCH 3 ), trimethylethoxysilane ((CH 3 ) 3 SiOC 2 H 5), hexamethyldisilazane ([(CH 3 ) 3 Si] 2 NH), hexaphenyldisiloxane ([(C 6 H 5 ) 3 Si] 2 O), etc.; the amino-silane end-capping agents include but are not limited to dimethylsiloxydimethylsilane (HMe 2 SiOSiMe 2 H), dimethylsilazodimethylsilane (HMe 2 SiNSiMe 2 H), dimethylethoxysilane (HMe 2 SiOEt), etc.

[0041] The present invention also provides the uses of the above-mentioned high refractive index transparent photocurable mercaptoaryl silicone oil and the silicone materials prepared therefrom, so as to enrich the types of silicone materials and expand the application fields of silicone polymers, especially in high-end fields such as topological structure silicone materials, end-functionalized silicone resins, optical silicone coatings, 3D printing silicone materials and optical fibers, etc., which have significant application values. For example, in the field of UV-LED packaging, this material can transmit and focus light more effectively, improving the luminous efficiency and light output quality of the LED; in the aspect of optical fiber coatings, this material can provide good protection performance and optical performance, ensuring the stable transmission of optical signals; in 3D printing materials, its photocuring characteristics and high refractive index make it an ideal choice for manufacturing high-precision optical devices and complex structures.

[0042] The beneficial effects of the present invention are as follows:

[0043] (1) Under the premise of photocuring, the present invention successfully realizes the dual characteristics of high refractive index (greater than 1.60) and rapid photocuring by introducing aryl and mercapto groups. Compared with the prior art, the present invention not only improves the refractive index of the mercaptoaryl silicone oil, but also significantly shortens the curing time, and does not require the use of organic solvents, having higher environmental protection and economy.

[0044] (2) The present invention simultaneously introduces aryl and mercapto groups into the polysiloxane chain. This innovative strategy not only enriches the structural diversity of polysiloxanes, but also realizes the precise regulation of their properties. The introduction of aryl groups significantly improves the refractive index of the silicone oil, enabling it to meet the application scenarios with strict requirements for optical properties; while the addition of mercapto groups endows the material with photocuring characteristics, that is, it can be rapidly cured under specific light irradiation conditions, greatly improving the processing efficiency and the stability of the material.

[0045] (3) The present invention forms a polymer with a specific structural formula by precisely controlling the ratio of each R group, thereby achieving perfect synergy between high refractive index and photocuring function.

[0046] (4) In the preparation process of the present invention, a one-step hydrolysis and polycondensation method is used, which greatly simplifies the preparation process and abandons the traditional multi-step reaction and the use of organic solvents. It not only reduces the reaction steps and solvent treatment, but also reduces the pollution to the environment, which is in line with the development trend of green chemistry. In combination with the direct purification technology, the reaction product is treated with anhydrous sodium carbonate to further improve the purity and yield of the product (up to 87.44%), which not only reduces the production cost but also improves the market competitiveness.

[0047] (4) The high-refractive-index transparent photocurable mercapto aromatic silicone oil provided by the present invention has successfully filled the market gap with its excellent performance and unique structure, and has provided an ideal material choice for multiple emerging fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 FTIR spectrum of PDMS-SD-03.

[0049] Figure 2 Characterization of PDMS-SD-03 1 H-NMR spectrum.

[0050] Figure 3 Characterization of PDMS-SD-03 13 C-NMR spectrum.

[0051] Figure 4 This is the UV-visible light transmittance diagram of PDMS-SD-03. DETAILED DESCRIPTION

[0052] The present invention is further described below in conjunction with specific embodiments and accompanying drawings, but the present invention is not limited thereto. The methods involved in the present invention are commonly used methods in the art unless otherwise specified, and the reagents involved are all available from common commercial channels unless otherwise specified.

[0053] The present invention adopts the following methods to characterize and perform performance tests on the following embodiments and comparative examples:

[0054] (1) Fourier transform infrared spectroscopy (FTIR)

[0055] The ALPHA-11 Fourier infrared spectrometer of the German BRUKER Spectroscopy Instrument Company was used, with a scanning range of 4000-600 cm -1 , resolution 4cm -1 , obtained by scanning 16 times.

[0056] (2) Proton Nuclear Magnetic Resonance 1 H-NMR)

[0057] 1 H-NMR: At room temperature, 1,4-dioxane was used as the internal standard and CDCl 3 was used as the solvent. The contents of mercapto SC% (Formula 1) and phenyl -Ph% (Formula 2) were measured by 1 the H-NMR internal standard method

[0058]

[0059] where M SC is the mole fraction of mercaptopropyl in 100 g of the sample, mol / 100 g; W i is the mass of the internal standard 1,4-dioxane, g; W s is the mass of the test sample, g; A is the peak area of -CH 2 - connected to mercaptopropyl; B is the peak area of -CH 2 - proton H in 1,4-dioxane.

[0060]

[0061] where M Ph is the mole fraction of phenyl in 100 g of the sample, mol / 100 g; W i is the mass of the internal standard 1,4-dioxane, g; W s is the mass of the test sample, g; A is the peak area of -C-H on the phenyl, m 2 ; B is the peak area of -CH 2 - proton H in 1,4-dioxane, m 2 .

[0062] (3) TGA Test: The thermal stability of the test sample was measured using a NETZSCH TG 209 thermogravimetric analyzer. The sample mass was 2 - 5 mg, the N 2 flow rate was 20 mL / min, the test temperature range was 30 - 800 °C, and the heating rate was 10 °C / min.

[0063] (4) Density Test: A QBB-37 density cup from Shanghai Huake Experimental Equipment Co., Ltd. was used and measured according to ISO 2811.

[0064] (5) Viscosity Test: An NTV-S1 digital rotational viscometer from Shanghai Nirun Intelligent Technology Co., Ltd. was used and measured according to ISO 2555.

[0065] (6) Refractive index test: Measured using a 2WA-J Abbe refractometer from the Fifth Factory of Shanghai Optical Instruments according to GB / T 14851-2018.

[0066] (7) UV-visible light transmittance test: Measured using a UV-mini-1240 UV-visible spectrophotometer from SHIMAZU Corporation, Japan according to ASTM D1003-13.

[0067] Example 1

[0068] Take hexamethyldisiloxane (0.97 g, 0.006 mol), dimethyldiethoxysilane (113.33 g, 0.84 mol), deionized water, and concentrated hydrochloric acid and add them to a 500 mL straight four-necked flask equipped with a mechanical stirrer, thermometer, condenser, and constant pressure funnel. Heat up to 60 °C and keep warm for 1 h; then use the constant pressure funnel to dropwise add a mixture of 3-mercaptopropylmethyldimethoxysilane (82.90 g, 0.46 mol) and diphenyldimethoxysilane (74.71 g, 0.31 mol) within 10 min. After the addition is complete, keep warm at 75 °C for 2 h; then evacuate to transparency under the conditions of -0.1 MPa and 85 °C. After cooling to room temperature, add sodium carbonate powder and stir for 1 h, then continue vacuum distillation until transparent, and let stand for 20 min until the solid settles. Take the upper clear liquid. Obtain a high refractive index transparent photocurable mercaptoaryl silicone oil PDMS-SD-01, 159.3 g, with a yield of 79.65%.

[0069] Take 2.5 g of PDMS-SD-01 silicone oil, 16.65 g of vinyl-terminated silicone oil, 16.15 g of vinyl silicone resin, and 0.35 g of photoinitiator 1173. After stirring evenly, remove air bubbles under vacuum, and obtain an organosilicon material UVLED-01 after curing by UV light radiation.

[0070] Example 2

[0071] Take hexamethyldisiloxane (0.97 g, 0.006 mol), dimethyldiethoxysilane (47.91 g, 0.36 mol), deionized water, and concentrated hydrochloric acid and add them to a 500 mL straight four-necked flask equipped with a mechanical stirrer, thermometer, condenser, and constant pressure funnel. Heat up to 60 °C and keep warm for 1 h; then use the constant pressure funnel to dropwise add a mixed solution of 3-mercaptopropylmethyldimethoxysilane (104.88 g, 0.58 mol) and diphenyldimethoxysilane (94.74 g, 0.39 mol) within 10 min. After the dropping is completed, keep warm at 75 °C for 2 h; then evacuate to transparency under the conditions of -0.1 MPa and 85 °C. After cooling to room temperature, add sodium carbonate powder and stir for 1 h, then continue vacuum distillation until transparent, and let stand for 20 min until the solid settles. Take the upper clear liquid. Obtain high refractive index transparent photocurable mercaptoaryl silicone oil PDMS-SD-02, 169.2 g, with a yield of 84.6%.

[0072] Take 2.5 g of PDMS-SD-02 silicone oil, 14.40 g of vinyl-terminated silicone oil, 13.96 g of vinyl silicone resin, and 0.31 g of photoinitiator 1173. After stirring evenly, remove air bubbles under vacuum, and obtain the silicone material UVLED-02 after curing by UV light radiation.

[0073] Example 3

[0074] Take hexamethyldisiloxane (0.406 g, 0.0025 mol), dimethyldiethoxysilane (28.77 g, 0.214 mol), 3-mercaptopropylmethyldimethoxysilane (77.29 g, 0.428 mol), diphenyldimethoxysilane (157.09 g, 0.643 mol). At room temperature, then at a rotation speed of 200, use a constant pressure funnel to inject a mixed solution of trifluoromethanesulfonic acid (2.63 g, 0.0175 mol) and deionized water (37.03 g, 2.036 mol) into the four-necked flask; after the injection is completed, add the mixed solution to a 500 mL straight four-necked flask equipped with a mechanical stirrer, thermometer, and condenser, and gradually heat up to 75 °C. After the heating is completed, keep the temperature constant for 3.5 h. After the constant temperature is completed, carry out vacuum distillation (not exceeding 95 °C) under a -0.1 MPa environment until the system is transparent. After cooling to room temperature, add anhydrous sodium carbonate and stir, and then continue vacuum distillation for 10 - 15 min. Filter while it is hot and take the liquid phase. Obtain high refractive index transparent photocurable mercaptoaryl silicone oil PDMS-SD-03, 133.2 g, with a yield of 88.8%.

[0075] Take 2.5 g of PDMS-SD-03 silicone oil, 15.40 g of vinyl-terminated silicone oil, 14.96 g of vinyl silicone resin, and 0.32 g of photoinitiator 1173. After stirring evenly, remove air bubbles under vacuum, and obtain the silicone material UVLED-03 after curing by UV light radiation.

[0076] Example 4

[0077] Take hexamethyldisiloxane (0.406 g, 0.0025 mol), dimethyldiethoxysilane (24.41 g, 0.182 mol), 3-mercaptopropylmethyldimethoxysilane (78.69 g, 0.426 mol), diphenyldimethoxysilane (159.94 g, 0.655 mol). At room temperature, then at a speed of 200 rpm, use a constant pressure funnel to inject a mixed solution of trifluoromethanesulfonic acid (2.63 g, 0.0175 mol) and deionized water (36.65 g, 2.036 mol) into the four-necked flask; after the injection is completed, add the mixed solution to a 500 mL straight four-necked flask equipped with a mechanical stirrer, a thermometer, and a condenser, gradually heat up to 75 °C, and keep the temperature constant for 3.5 h after the heating is completed. After the constant temperature is completed, carry out vacuum distillation (not exceeding 95 °C) under an environment of -0.1 MPa until the system is transparent. After cooling to room temperature, add anhydrous sodium carbonate and stir, and then continue vacuum distillation for 10 - 15 min, and filter while it is hot to obtain the liquid phase. Obtain 141.8 g of high refractive index transparent photocurable mercaptoaryl silicone oil PDMS-SD-04, with a yield of 94.5%.

[0078] Take 2.5 g of PDMS-SD-04 silicone oil, 16.58 g of vinyl-terminated silicone oil, 16.95 g of vinyl silicone resin, and 0.35 g of photoinitiator 1173. After stirring evenly, carry out vacuum degassing, and obtain the silicone material UVLED-04 after curing by UV light radiation.

[0079] The four different PDMS-SDs with different (3-mercaptopropylmethyldimethoxysilane + diphenyldimethoxysilane) / dimethyldiethoxysilane values prepared by the hydrolysis-polycondensation method in the above examples. Among them, IR analysis was carried out on PDMS-SD-03, 1 H-NMR and 13 C-NMR analysis, as Figure 1 , Figure 2 and Figure 3 shown, which conforms to the following general formula:

[0080] [(CH 3 ) 3 SiO 1 / 2 a [(CH 3 ) 2 SiO 2 / 2 b [(Ph) 2 SiO 2 / 2 c [(CH 3 )(CH 2 CH​​​2 CH 2 SH)SiO 2 / 2 d

[0081] IR(cm -1 ):3068cm -1 is the absorption peak of C-H stretching vibration in the benzene ring; 2960cm -1 , 2939cm -1 are respectively the absorption peaks of C-H stretching vibration of Si-CH 3 and Si-CH 2 CH 2 CH 2 SH for the methyl and methylene groups; 2575cm -1 , 796cm -1 are respectively the absorption peaks of stretching vibration and bending vibration of –SH; 1600 - 1450cm -1 is the continuous peak of the skeletal stretching vibration of the benzene ring; 1429cm -1 is the absorption peak of antisymmetric deformation vibration of Si-CH 3 ; 1345cm -1 is the absorption peak of deformation vibration of -CH 2 CH 2 CH 2 SH; 1250cm 2 is the absorption peak of symmetric deformation vibration of Si-CH -1 ; 1056 - 1005cm 3 is the continuous peak of Si-O-Si stretching vibration and asymmetric bending vibration. -1

[0082] Figure 1 From it can be seen that obvious characteristic absorption peaks of -SiCH 2 CH 2 CH 2 SH, C=C in the benzene ring, C-H in the benzene ring, Si-O-Si and Si-CH 3 appear, and there is no stretching vibration peak of hydroxyl O-H near 3480cm -1 , indicating that the Si-OH bond is completely condensed.

[0083] 1 H-NMR(δ ppm, CDCl 3 , 400MHz): δ(ppm) = 7.52 - 7.76 and 7.23 - 7.50(m, 5H, -Ph), 3.65 - 3.70(s, 8H, dioxane), 2.33 - 2.65(d, 2H, -CH 2 ​S-), 1.60 - 1.80 (m, 2H, -CH 2 -), 1.12 - 1.49 (m, 2H, -SiCH 2 -), 0.53 - 0.90 (m, 1H, -SH), 0.03 - 0.38 (m, 3H, -SiCH 3 ).

[0084] From Figure 2 it can be seen that there are obvious -Ph hydrogen proton peaks, methylene hydrogen proton peaks on the mercaptopropyl group, and Si-CH 3 hydrogen proton peaks, indicating that the phenyl group and the mercaptopropyl group have been successfully introduced into PDMS-SD.

[0085] Before the reaction 13 C NMR (101 MHz, CDCl 3 ): δ (ppm) = -4.70 (S-CH 3 ) in KH970, 3.10 (Si-CH 3 ) of dimethyldiethoxysilane, 8.00 (Si-CH 3 ) in MM, 18.55 (-O-CH 2 -CH 3 ) of dimethyldiethoxysilane, 27.18 (-CH 2 -CH 2 -CH 2 -SH) in KH970, 50.88 (-OCH 3 ) in DDS, 51.11 (-OCH 3 ) in KH970, 58.23 (-O-CH 2 -CH 3 ) of dimethyldiethoxysilane, 127 - 134.82 (-Ph) in DDS;

[0086] After the reaction 13 C NMR (101 MHz, CDCl 3 ): δ (ppm) = -0.86 (Si-CH 3 ), 0.59 (Si-CH 3 ), 0.81 (Si-CH 3 ), 15.93 - 16.15 (-O-CH 2 -CH 3 ), 27.55 (-CH 2 -CH 2 -CH 2 -SH), 127.40 - 134.25 (-Ph).

[0087] From Figure 3It can be seen that Si-OMe and Si-O-CH in the reactants 2 CH 3 can be completely hydrolyzed and polycondensed, indicating that diphenyldimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, dimethyldiethoxysilane and hexamethyldisiloxane can be completely hydrolyzed and polycondensed into PDMS-SD.

[0088] Comparative Example 1

[0089] Methylvinyldiethoxysilane (16.00 g, 0.1 mol), (8.50 g, 0.06 mol), ethyl acetate (612.50 g) and p-toluenesulfonic acid (0.196 g) were mechanically stirred at 100 °C for 36 h under N 2 protection, then (8.50 g, 0.06 mol) and p-toluenesulfonic acid (0.196 g) were added, and then mechanically stirred at 80 °C for 42 h. After cooling to room temperature, it was washed twice with saturated aqueous NaHCO 3 solution, the oil layer was taken, dried with anhydrous MgSO4, rotary evaporated, and then vacuum concentrated to obtain unsaturated symmetric cyclic thiosilane monomer C 9 H 10 SiS 2 .

[0090] 3-Mercaptopropylmethyldimethoxysilane (63.12 g, 0.35 mol), unsaturated symmetric cyclic thiosilane monomer C 9 H 10 SiS 2 (63.00 g, 0.3 mol), benzene (252.24 g) and photoinitiator 2,4,6-trimethylbenzoyl diphenylphosphine oxide TPO-L (0.63 g) were mechanically stirred for 30 min, and then at a maximum irradiation intensity of 100 mW / cm 2, under ultraviolet light with a wavelength range of 200 - 400 nm, after performing the thiol-ene photo-click reaction for 10 min, mercaptopropylmethyldimethoxysilane (90.00 g, 0.50 mol) and diphenyldiethoxysilane (53.07 g, 0.195 mol) were added. After mechanical stirring for 20 min, 1,10-decanediyl dimethacrylate (102.30 g, 0.32 mol) and trifluoromethanesulfonic acid (0.54 g) were added. At 75 °C, deionized water (30.10 g, 1.672 mol) was added dropwise. After the addition was complete, a hydrolysis-polycondensation reaction was carried out for 14 h. Then, a capping agent MM (0.81 g, 0.005 mol) and magnesium sulfate (188.45 g) were added and the temperature was raised to 80 °C for equilibrium telomerization for 5 h. After cooling, the mixture was washed three times with a saturated sodium carbonate solution of 50% ethanol-water and a demulsifier SP-169 (1.56 g) was added, shaken well and allowed to stand for phase separation. The organic layer was taken and distilled under reduced pressure at 30 - 40 °C and -0.095 MPa for 40 min. Then, it was washed with secondary distilled water and a demulsifier SP-169 (1.56 g) was added, shaken well and allowed to stand for phase separation. The oil layer was taken and distilled under reduced pressure at 70 - 90 °C and -0.095 MPa for 60 min. After purification by column chromatography (methanol / chloroform = 15 / 2, mass ratio), a high refractive index thiol silicone oil HIRS-Si0 was obtained. 2 , 189.19 g, and the yield was 87.44%.

[0091] Comparative Example 2

[0092] Dimethylcyclosiloxane (207.2 g), diphenyltetramethyldisiloxane (51.6 g), octaphenylcyclotetrasiloxane (237.6), and potassium hydroxide (0.5 g, 5 wt%) base gum catalyst were added to a four-necked flask. The temperature was slowly raised to 50 - 60 °C, and the vacuum was adjusted to -0.09 MPa for dehydration. The dehydration time was 2 hours. Then, the temperature was raised to 170 - 180 °C for polymerization reaction. When the polymerization reached equilibrium for 6 hours, the temperature was lowered to 120 °C. Trimethylsilyl phosphate (0.3 g) was dissolved in octamethylcyclotetrasiloxane (5 g) and added to the flask. After continuous stirring for 1 hour, the vacuum was pumped to a pressure below 100 Pa, and the temperature was raised to 280 °C to remove low-boiling components until no more effluent was obtained. Then, it was cooled and filtered to obtain a colorless and transparent phenyl dimethyl-capped methylphenyl silicone oil PDMS-Ph-01, 118.35 g, and the yield was 60.23%.

[0093] The relevant properties of the silicone oils prepared in Examples 1 - 4 and Comparative Examples 1 - 2 and silicone materials were tested, and the test results are shown in Tables 1, 2, 3, and 4 below:

[0094] Table 1

[0095]

[0096] Table 2

[0097]

[0098] Table 3

[0099]

[0100]

[0101] Table 4

[0102]

[0103] As can be seen from Table 1, Table 2, Table 3 and Table 4, the UV-curable high refractive index mercaptophenyl silicone oil prepared by the present invention is a colorless, transparent and viscous substance, with a mercapto content of 0.10 - 0.50 mol / 100 g, a phenyl content of 0.30 - 0.90 mol / 100 g, a relatively uniform molecular weight distribution, a high refractive index, a moderate viscosity and high storage stability. Through TGA testing, after the prepared mercaptophenyl silicone oil is cured, the T5% values are all greater than 320 °C, the T50% values are all greater than 540 °C, and the residue rates are all less than 5%, indicating that the present invention has excellent thermal stability and low residue rate characteristics. Figure 4 This is the UV-visible light transmittance diagram of PDMS-SD-03. It can be seen that the light transmittance of the present invention at 450 nm is greater than 92%.

[0104] Thus, by combining the present invention with PDMS-SD, vinyl-terminated silicone oil, vinyl silicone resin and photoinitiator, an organosilicon LED encapsulation composite material with high refractive index and light transmittance is prepared through formula design. After curing, it has suitable mechanical strength, is transparent in appearance, and can be applied to fields such as aerospace, electronic appliances, and high-temperature sealing that require high temperature resistance or strict environmental pollution requirements. Especially in the fields of optical materials, optoelectronic devices, 3D printing, etc., it has broad application prospects and significant technical advantages and market potential.

[0105] It can be understood that the above specific embodiments are all further descriptions of the present invention and are not used to limit the protection scope of the present invention. For those skilled in the art, all other retouches and modifications obtained without creative labor belong to the protection scope of the present invention.

Claims

1. A high refractive index transparent photocurable mercapto aromatic silicone oil, characterized in that: It conforms to the following general formula: (R 1 R 2 R 3 SiO 1 / 2 ) a (R 4 R 5 SiO 2 / 2 ) b (R 6 R 7 SiO 2 / 2 ) c (R 8 R 9 SiO 2 / 2 ) d ; Among them, R 1 , R 2 and / or R 3 A hydrogen atom or a hydrocarbon group without an aliphatic unsaturated bond; Among them, R 4 is an aromatic hydrocarbon group; R 5 An aromatic hydrocarbon group or a hydrocarbon group without an aliphatic unsaturated bond; Among them, R 6 is a monovalent hydrocarbon group containing a mercapto group and not containing an aliphatic unsaturated bond; R 7 is methoxy or methyl; Among them, R 8 and / or R 9 is an alkyl group; Among them, 1>a, b, c and d>0.

2. The high refractive index transparent photocurable mercapto aromatic silicone oil according to claim 1, characterized in that: In the general formula, a, b, c and d satisfy: 1≤(b+c) / d≤8 and a+b+c+d=1 and 0.2≤b≤0.5 and 0.1≤c≤0.3 and 0≤d≤0.

4.

3. The high refractive index transparent photocurable mercapto aromatic silicone oil according to claim 1, characterized in that: In the general formula, R 1 , R 2 and R 3 It is methyl.

4. The high refractive index transparent photocurable mercapto aromatic silicone oil according to claim 1, characterized in that: The high refractive index transparent photocurable mercapto aryl silicone oil has a mercapto content of 0.10-0.50 mol / 100 g and an aryl content of 0.30-0.90 mol / 100 g.

5. The high refractive index transparent photocurable mercapto aromatic silicone oil according to claim 1, characterized in that: The high refractive index transparent photocurable mercapto aromatic silicone oil has a dynamic viscosity of 800-40000 mPa·s at 25° C., a refractive index of 1.46-1.70 at 25° C., and a light transmittance of ≥85% at 450 nm.

6. A method for preparing the high refractive index transparent photocurable mercapto aromatic silicone oil according to claim 1, characterized in that: The method comprises the following steps: reacting a silane monomer containing a hydrolyzable group, a capping agent and deionized water by a hydrolysis polycondensation method under the promotion of acid, alkali, salt or metal oxide to obtain the high refractive index transparent photocurable mercaptophenyl silicone oil.

7. The method for preparing the high refractive index transparent photocurable mercapto aromatic silicone oil according to claim 6, characterized in that: The silane monomer containing a hydrolyzable group includes a mercaptosilane monomer and an arylsilane monomer.

8. An organosilicon material, characterized in that: It is prepared from the high refractive index transparent photocurable mercapto aromatic silicone oil as described in claim 1.

9. A method for preparing the organosilicon material according to claim 8, characterized in that: The following steps are involved: The high refractive index transparent photocurable mercapto aromatic silicone oil, terminal vinyl silicone oil, anchoring agent and photoinitiator are uniformly stirred, and mercapto-ene photoclick chemistry is carried out under ultraviolet light for crosslinking and curing to obtain the organosilicon material.

10. Use of the high refractive index transparent photocurable mercapto aromatic silicone oil according to claim 1 or the organosilicon material according to claim 8.

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