CN113201138B

CN113201138B - Transparent light-curable high-refractive-index mercapto silicone oil and preparation method thereof

Info

Publication number: CN113201138B
Application number: CN202110300019.8A
Authority: CN
Inventors: 刘珠; 肖定书; 熊前程; 申玉求; 李险峰
Original assignee: Huizhou Dayawan Huida Chemical Research Institute Co ltd; Huizhou University
Current assignee: Huizhou Qiangda Electronic Co ltd
Priority date: 2021-02-03
Filing date: 2021-03-22
Publication date: 2022-11-22
Anticipated expiration: 2041-03-22
Also published as: CN113201138A

Abstract

The invention discloses a transparent light-curable high-refractive-index mercapto silicone oil and a preparation method thereof, wherein the structural formula of the mercapto silicone oil is as follows: (R) ₁ R ₂ R ₃ SiO _1/2 ) _a (R ₄ R ₅ SiO) _b (R ₆ CH ₃ SiO) _c (R ₇ CH ₃ SiO) _d Wherein R is ₁ 、R ₂ And R ₃ Are identical or different hydrogen radicals, monovalent hydrocarbon radicals free of aliphatic unsaturation or unsaturated hydrocarbon radicals of 2 to 10 carbon atoms; r ₄ And R ₅ Is a monovalent hydrocarbon group or aromatic hydrocarbon group free of aliphatic unsaturation and containing at least one aromatic hydrocarbon group; r ₆ Has the structure of- (CH) ₂ ) _e S‑CH ₂ CH ₂ R ₀ Wherein e is a positive integer of 1 to 3, R ₀ Is a symmetric episulfide heterocyclic silicon-based group and has n sulfur atoms, and n is an integral multiple of 2; r ₇ Has a structure of- (CH) ₂ ) _f SH and f are positive integers of 1 to 3. The high-refractive-index mercapto silicone oil prepared by the invention is transparent, can be quickly cured, has a high refractive index, and is stable at room temperature, good in storage stability and low in odor. In addition, the invention adopts a one-pot two-step method, has simple and convenient preparation process, high production efficiency, lower cost and no harsh reaction conditions, and is easy to realize industrial production.

Description

Transparent light-curable high-refractive-index mercapto silicone oil and preparation method thereof

Technical Field

The invention relates to a high polymer material, in particular to transparent light-curable high-refractive-index mercapto silicone oil and a preparation method thereof.

Background

At present, the vulcanization molding process of the organic silicon polymer mainly adopts a room temperature and high temperature vulcanization molding process, and the organic silicon polymer can be safely used after long-time room temperature or high temperature heat curing and post curing, cannot realize continuous operation production and consumes serious time; the high-temperature vulcanization process is usually carried out at 150-180 ℃, which is not beneficial to the co-molding with a heat-sensitive component, and has long molding time, limited application occasions and serious energy consumption. In addition, no matter the room-temperature vulcanized silicone rubber or the high-temperature vulcanized silicone rubber, the vulcanization process is lack of space-time controllability, the ultraviolet curing (UV-curing) technology is a new fast, efficient, energy-saving and environment-friendly technology, the energy consumption is only 1/5-1/10 of that of thermosetting, and the fast curing molding can be realized within a few seconds. However, due to the commercial photosensitive silicone raw materials, the existing silicone polymers are difficult to realize rapid UV light curing molding. Therefore, the polysiloxane chain needs to be subjected to photosensitization modification in advance, but the photocuring group has certain polarity, so that the gel is easy to gel and is difficult to be transparent in the preparation process, the photocuring rate is greatly limited, and the preparation difficulty is increased.

Click chemistry is widely applied to the construction of functional polymers due to wide raw material sources, rapidness, high efficiency, mild conditions, high reaction rate, simple and convenient separation and purification, chemical solvent resistance, good stereoselectivity and the like. The mercapto-ene (thiol-ene) light click reaction is the most important type in click chemistry, and has the characteristics of click reaction and light-space controllability. Although the mercapto polysiloxane has been reported in the literature and patents, it is mainly limited to the technical monopolies of the laboratory and foreign industries, such as Xingyue, meiji and Dow Corning. [ HongPing Xiang, xiiaowei Wang, zhirong Ou, guinghong Lin, jingfeng Yin, zhu Liu, lanyue Zhang, xiiaoxu Liu, UV-curable,3D printable and biocompatable silicone elastomers J ], progressive in Organic Coatings,2019,137,105372], a transparent mercaptodimethylpolysiloxane was prepared by hydrolysis-polycondensation, the curing kinetics, biocompatibility and 3D printing properties of mercapto-ene photopolymerization were studied, and the studies showed that mercaptodimethylpolysiloxane and vinyl silicone oil can be rapidly cured and molded by mercapto-ene photopolymerization and can be applied to SLA3D printing of various silicone rubber elastomers. (Justin M.Sirrine, alisa ZLatanic, viswanth Meenakshindaram, jamie M.Messman, christopher B.Williams, petar R.Dvornic, and Timothy E.Long.) 7000g/mol of the mercapto-ene photopolymerization fast crosslinking properties of mercapto polysiloxanes with vinylphenyl silicone oils and vinylethyl silicone oils, available from GELEST, applied to 3D printing. Liu Zhu, hong Peng, hong Ping, huang Ziying, luo Qinghong, yang Xianjun, liu Xiaoxuan, preparation of a double cross-linked network silicone elastomer and self-repairing performance research thereof [ J ] Polymer science, 2020, 51 (6): 656-669], colorless transparent mercapto silicone oil (PDMS-SH) with different mercapto contents is prepared by a hydrolysis-condensation method, and then a reversible/irreversible hybrid double cross-linked network is constructed by a light-induced click reaction of the PDMS-SH and terminal vinyl silicone oil and thermally reversible dynamic ion cross-linking of carboxyl silicone oil and amino silicone oil, so that the silicone transparent elastomer with rapid UV curing and excellent self-repairing performance is prepared.

However, the above-mentioned mercaptopolysiloxane is not only limited to the small sample preparation stage in the laboratory, and industrialization cannot be realized, and the refractive index of the prepared mercaptopolysiloxane is generally low, and the refractive index is basically not higher than 1.50. The requirement of high refractive index mercapto polysiloxane can not be met.

With the rapid development of modern optics, photoelectrons, information technology and the like, products are continuously researched towards high transparency, high refractive index, high light transmission and high reliability. The research direction comprises LED packaging materials, gradient refractive index materials, nonlinear optical materials, environment-friendly optical materials, liquid crystal materials, light wave materials and the like, the materials have certain requirements on the refractive index, and the higher the refractive index is, the better the general performance is. The organic silicon polymer has wide application value in the fields of optical lenses, optical coatings, optical adhesives, optical glass, optical fibers, optical plastics, flexible displays and the like due to environmental protection, no toxicity, excellent mechanical properties, high and low temperature resistance, elasticity, physiological inertia and the like. However, this requires silicone polymers that have higher refractive indices while maintaining high transparency and mechanical strength. Generally, the way of improving the silicone polymer is mainly to introduce high refractive index groups on the molecular chain of polysiloxane, and the method is as follows:

(1) The introduction of condensed ring and aromatic group can effectively improve the refractive index of the organic silicon polymer, but too much introduction can cause large dispersion, and the mechanical property is hard and brittle, thus influencing the use. In the allowable range of mechanical properties, the refractive index of the organic silicon polymer is improved only by about 1.54 generally by introducing a benzene ring;

(2) The introduction of halogen group (except fluorine group) can effectively improve the refractive index, but has the problems of higher density, poor weather resistance, easy yellowing and the like;

(3) Introduction of heavy metal ions (e.g. lead, lanthanum or TiO) ₂ PbS and FeS nano particles) can improve the refractive index, but have the problems of high density, low impact resistance, easy yellowing, difficult practicability and the like;

(4) The introduction of aliphatic polycyclic groups can improve the refractive index, but simultaneously has the problems of lower dispersion, low mechanical property and the like;

(5) The refractive index can also be improved by introducing a group containing N, P, S and other elements.

Among the above methods, introduction of an S element into a polysiloxane molecular chain is the most effective method for improving the refractive index, and the prepared polysiloxane material has low dispersion and high environmental stability, and is a research hotspot in recent years. The sulfur element is generally introduced to the polysiloxane chain in the form of thioether bond, thioester bond, thiocarbamate, sulfone group, episulfide, etc. to prepare the high refractive index optical silicone polymer. The polysiloxane material introduced in a thioether bond form can obviously improve the sulfur content, thereby effectively improving the refractive index of the polysiloxane material, but still has the problems of large pungent smell, easy yellowing, poor mechanical property and the like. As disclosed in PCT patent WO2013/172921, chinese patent zl201380037447.X, CN201711500598.0, CN201711500599.5, CN201811015411.2, the introduction of symmetric episulfide groups can improve the refractive index of polysiloxane materials while effectively solving the problem of pungent odor, but there is still a risk of ring opening of the episulfide groups during high temperature curing, which causes problems of pungent odor and decrease of refractive index. Therefore, the refractive index of the currently marketed optical organosilicon material is mainly improved by introducing a benzene ring structure, the mechanical property is greatly reduced, and the improvement of the refractive index is greatly limited, so that the application of the optical organosilicon material in high-end fields such as optical lenses, lens materials, optical instruments, flexible optical fibers and optical bonding glue is limited. At present, the way of introducing sulfur element into polysiloxane material to improve refractive index is mainly in the laboratory research stage, and is a research hotspot of researchers.

Therefore, the high-refractive-index three-dimensional polysiloxane material which is constructed by utilizing the sulfydryl-alkene light click reaction and introducing the episulfide structure without pungent smell and can be quickly cured at room temperature has good application prospect, has high curing speed, is not easily affected by oxygen inhibition in the reaction process, is easy to release shrinkage stress, can effectively reduce the internal stress of a cured product, can not cause the warping deformation of the product, has high refractive index and good light transmittance, and is particularly suitable for the photoelectric application fields of optical devices, electronic materials, optical coatings, optical fibers and the like.

Disclosure of Invention

The invention aims to provide high-refractive-index mercapto silicone oil capable of being rapidly cured and a preparation method thereof, so as to overcome the defects that in the prior art, an organic silicon polymer is long in thermosetting time, time-consuming and energy-consuming, and generally low in refractive index.

In order to realize the purpose, the invention adopts the following technical scheme:

the invention provides a light-curable high-refractive-index mercapto silicone oil and a preparation method thereof. The technical scheme is a one-pot two-step method, firstly, a symmetrical episulfide silicon-based modified silane monomer (SES-Si) is prepared through sulfydryl-alkene photopolymerization, and then, the high-refractive-index sulfydryl silicone oil is prepared through a hydrolysis-polycondensation method. Due to the structural particularity of the mercapto silicone oil, the prepared mercapto silicone oil with high refractive index is transparent, can be quickly cured, has a high refractive index, and is stable at room temperature, good in storage stability and low in smell. In addition, the invention adopts a one-pot two-step method, has simple and convenient preparation process, high production efficiency, lower cost and no harsh reaction conditions, and is easy to realize industrial production.

The structural general formula of the mercapto silicone oil with high refractive index is as follows:

(R ₁ R ₂ R ₃ SiO _1/2 ) _a (R ₄ R ₅ SiO) _b (R ₆ CH ₃ SiO) _c (R ₇ CH ₃ SiO) _d

wherein R is ₁ 、R ₂ And R ₃ Are identical or different hydrogen radicals, monovalent hydrocarbon radicals free of aliphatic unsaturation or unsaturated hydrocarbon radicals of 2 to 10 carbon atoms; r ₄ And R ₅ Is a monovalent hydrocarbon group or aromatic hydrocarbon group free of aliphatic unsaturated bonds and containing at least one aromatic hydrocarbon group; r ₆ Has the structure of- (CH) ₂ ) _e S-CH ₂ CH ₂ R ₀ Wherein e is a positive integer of 1 to 3, R ₀ Is a symmetric episulfide heterocyclic silicon-based group and has n sulfur atoms, and n is an integral multiple of 2; r ₇ Has a structure of- (CH) ₂ ) _f SH and f are positive integers of 1 to 3.

Preferably, a, b, c and d are numbers which are more than 0 and less than 1, and 0.3 < c + d < 0.8,0 < c < 0.3, a +, b +, c + d =1.

Preferably, R ₀ Is a symmetric episulfide heterocyclic silicon-based group, the structure of which can be selected from

Etc. ofAnd (4) seed preparation.

More preferably, R ₀ Can be selected from

One or more of them.

Preferably, the sulfur-containing heterocyclic silicon-based group is a saturated symmetrical sulfur-containing heterocyclic group and has only one silicon atom.

Furthermore, the prepared mercapto-silicone oil is colorless transparent oily matter without pungent smell, the dynamic viscosity at 25 ℃ is 100-50000 mPa.s, the refractive index at 25 ℃ is 1.46-1.70, the visible light transmittance is not less than 98%, and the mercapto content is 0.15-0.85 mol/100g.

The invention also provides a preparation method of the transparent photocurable high-refractive-index mercapto silicone oil, and the specific preparation scheme is as follows:

mechanically pre-stirring mercaptosilane monomer 1, unsaturated symmetric episulfide silane monomer SES-Si, organic solvent and photoinitiator uniformly according to a certain proportion, and keeping the maximum irradiation intensity at 70-150 mW/cm ² Under the ultraviolet light with the wavelength range of 200-400 nm, carrying out sulfydryl-alkene light click reaction for 5-10 min, adding a certain amount of sulfydryl silane monomer 2 and aromatic alkoxy silane monomer, mechanically stirring and mixing uniformly, adding a certain amount of episulfide stabilizer and catalyst, dripping a certain proportion of deionized water at 60-80 ℃, after the deionized water is dripped, carrying out hydrolysis-polycondensation reaction for 12-16 h at 60-80 ℃, adding a blocking agent and an inert water absorbent at 80-90 ℃, carrying out telomerization for 2-5 h to obtain sulfydryl silicone oil with a certain viscosity, and purifying to obtain the light-curable high-refractive-index sulfydryl silicone oil.

Preferably, the mercaptosilane monomers 1 and 2 are one or more of mercaptopropylmethyldimethoxysilane, mercaptopropylmethyldiethoxysilane, mercaptomethylmethyldimethoxysilane and mercaptomethylmethyldiethoxysilane;

preferably, the structural formula of the unsaturated symmetric episulfide silane monomer SES-Si can be selected from any of the following structural formulas:

R ₀ alkenyl of 2 to 5 carbon atoms, which may be vinyl, allyl, butenyl, pentenyl, etc., of which vinyl is preferred; r ₁ Is C not containing aliphatic unsaturated bonds _1～10 A monovalent hydrocarbon group or hydrogen group which may be a methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group or similar alkyl groups and hydrogen group, etc., wherein a methyl group or hydrogen group is preferred; c _m 、C _n And C _x Is 0 to 6 linked methylene, of which C is preferred _m Wherein m is an integer of 0 to 6, C _n And C _x Wherein n and x are 0 or 1. The specific structure can be selected from the following:

one or more of them. The following may be preferred:

one or more of them.

The preparation method patent CN201810427762.8 discloses and verifies the structure, and the specific preparation method comprises the following steps:

mixing unsaturated methyldialkoxysilane, a dimercapto compound and a catalyst, reacting for 72-96 h at the reaction temperature of 80-100 ℃ in inert gas, washing with water, extracting and purifying to obtain the unsaturated symmetric episulfide silane monomer.

In order to prevent the self-polymerization phenomenon of the dimercapto compound in a reaction system and improve the yield, the preparation steps of the unsaturated symmetrical episulfide silane monomer are as follows: mixing unsaturated methyldialkoxysilane, a dimercapto compound and a catalyst, reacting for 36-48 h under the condition of inert gas at the reaction temperature of 80-100 ℃, then adding an equivalent amount of dimercapto compound and the catalyst, and reacting for 36-48 h at the temperature of 80-100 ℃ to obtain an unsaturated symmetric episulfide silane monomer, wherein the unsaturated methyldialkoxysilane: the mol ratio of dithiol compound is 1: 0.5-0.6, and the addition amount of the catalyst is 0.5-2% of the total weight of the unsaturated methyldialkoxy silane and the dithiol compound.

The preparation of the unsaturated symmetric episulfide silane monomer is carried out in an organic solvent system, wherein the organic solvent can be one of toluene, ethyl acetate, petroleum ether, diethyl ether, chloroform, dichloromethane, n-hexane, isopropanol, acetone, naphtha and tetrahydrofuran, and the addition amount is 20-30 parts of the total weight of the unsaturated methyldialkoxysilane and the dithiol compound. The catalyst is one of phenylmethanesulfonic acid, methanesulfonic acid and trifluoromethanesulfonic acid.

The unsaturated methyldialkoxysilane in the preparation of the unsaturated symmetric episulfide silane monomer is one of methyl vinyl dimethoxysilane, methyl vinyl diethoxysilane, methyl allyl dimethoxysilane, methyl allyl diethoxysilane and the like. The dimercapto compound is HS-CH ₂ CH ₂ -SH、HS-CH ₂ CH ₂ CH ₂ -SH、

One kind of (1).

And (3) water washing: the water washing solution is sodium carbonate or sodium bicarbonate saturated solution, and after water washing, layering is needed, and the product is an organic phase; the extraction and purification steps comprise drying the organic phase by a drying agent, rotary evaporation drying and vacuum concentration, wherein the drying agent is an inert drying agent which is anhydrous Na ₂ SO ₄ Anhydrous MgSO (MgSO) ₄ Anhydrous CaSO ₄ Anhydrous CaCl ₂ One or more of molecular sieve and silica gel.

Preferably, the organic solvent is a good solvent insoluble in water and has a boiling point lower than 120 deg.C, and can be one or more of toluene, benzene, chloroform, dichloromethane, pentane, cyclohexane, n-hexane, carbon tetrachloride, dichloroethane, and trichloroethane. Among them, one or more of toluene, benzene, chloroform, cyclohexane and n-hexane are preferable.

Preferably, the photoinitiator is selected from free radical photoinitiators, including benzoin and derivatives thereof, benzil and derivatives thereof, alpha-hydroxyalkylbenzones, alpha-aminoalkylbenzones, acylphosphine oxides, benzophenones, heterocyclic arones, and the like, such as 2-hydroxy-methylphenylpropane-1-one (Darocure 1173), 2,4,6-trimethylbenzoyl-diphenylphosphine oxide TPO,2,4,6-trimethylbenzoylphenylphosphonic acid ethyl ester TPO-L, 2-hydroxy-4- (2-hydroxyethoxy) -2-methylpropiophenone (Darocure 2959), 1-hydroxy-cyclohexylbenzophenone (Irgacure 184), 2-methyl-1- (4-methylthiophenyl) -2-morpholin-1-one (Irgacure 907), 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone (Irgacure 369), phenylbis (2,4,6-trimethylbenzoyl) phosphine oxide (Irgacure 819), 1,1' - (methylenebis-4,1-phenylene) bis [ 2-hydroxy-2-methyl-1-propanone ] (Irgacure benzophenone), 127 BP, 26-trimethylbenzophenone (DEMzxft 3926), trimethylthioacetone (DEMX 3926), anthracene ketone (CPITX 394), and the like. Among them, one or more of 2-hydroxy-methylphenylpropane-1-one (Darocure 1173), 2,4,6-trimethylbenzoyl-diphenylphosphine oxide TPO,2,4,6-trimethylbenzoylphenylphosphonic acid ethyl ester TPO-L, 2-hydroxy-4- (2-hydroxyethoxy) -2-methylphenylpropiophenone (Darocure 2959), and 1-hydroxy-cyclohexylbenzophenone (Irgacure 184) are preferable.

Preferably, the aromatic alkoxysilane monomer may have the structural formula: r ₈ R ₉ SiX ₂ X is a monovalent hydrolyzable group, preferably X is halogen, alkoxy or acyloxy. More preferably, the halogen is chlorine and the alkoxy is C ₁ ～C ₃ Alkoxy of (2), acyloxy being C ₁ ～C ₃ An acyloxy group of (1). R ₈ And R ₉ Is a monovalent hydrocarbon group or aromatic hydrocarbon group free of aliphatic unsaturated bonds and containing at least one aromatic hydrocarbon group. Preferably, the monovalent hydrocarbon group free of aliphatic unsaturation is a methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, or similar alkyl group; the aromatic hydrocarbon group is phenyl, tolyl, xylyl or similar aryl, benzyl, phenethyl, phenylpropyl or similar aralkyl, and contains at least one aromatic hydrocarbon group; more preferably, R ₈ And R ₉ Is methyl and phenyl, and at least contains one phenyl.

Preferably, the inert water absorbent is a water absorbent which does not participate in the reaction, mainly in order to continuously complex the water generated by the reaction, thereby increasing the reaction rate and the conversion rate of the mercapto silicone oil, and further shortening the time of the polycondensation reaction. Comprises one or more of magnesium sulfate, calcium sulfate, activated molecular sieve, anhydrous calcium chloride, anhydrous magnesium chloride and the like.

Preferably, the episulfide stabilizer is an aliphatic dibasic ester compound and is a structural stabilizer of the symmetric episulfide unsaturated silane monomer, so that ring opening of the symmetric episulfide unsaturated silane monomer at high temperature can be effectively prevented, and the structural stability and no pungent smell of the high-refractive-index mercapto silicone oil are ensured. The material comprises one or more of diethyl dihydroxymethylmalonate, diethyl D- (-) -tartrate, 2-methyl-2-acrylic acid-1,10-decanediol, ethylene distearate, diethylene glycol distearate, dipropylene glycol diacrylate, 2-methyl-2-acrylic acid-1,10-decanediol, lauryl acrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol diacrylate, 1,3-nonanediol acetate, dipropyl malonate, dibutyl adipate, dibutyl glutarate, diethylene glycol dipropionate, di-n-propyl succinate, dioctyl malonate, dimethyl adipate, diisopropyl succinate, dimethyl pimelate, dibutyl malonate, dibutyl glutarate and diethylene glycol dipropionate.

Preferably, the catalyst can be selected from one or more of the commonly used concentrated sulfuric acid with the mass fraction of 98%, concentrated hydrochloric acid with the mass fraction of 37%, trifluoromethanesulfonic acid or strong acid cation resin in order to promote the hydrolysis-polycondensation process.

Preferably, the end-capping agent is an end-capping agent commonly used in organosilicon polymerization, and comprises a hydrocarbyl silane end-capping agent or a hydrosilane end-capping agent, wherein the hydrocarbyl silane end-capping agent can be one or more of hexamethyldisiloxane, trimethylmethoxysilane, trimethylethoxysilane, hexamethyldisilazane and hexaphenyldisiloxane; the hydrosilane end-capping agent is HMe ₂ SiOSiMe ₂ H、HMe ₂ SiNSiMe ₂ H( ^H MM ^H )、HMe ₂ One or more of SiOEt.

Preferably, the molar ratio of the mercaptosilane monomer 1, the unsaturated symmetrical episulfide silane monomer SES-Si, the mercaptosilane monomer 2, the aromatic alkoxy silane monomer and the blocking agent is (1.05-1.2): 1: (1.5-5): (0.6-15): (0.01 to 0.5); the adding amount of the organic solvent is 1 to 3 times of the sum of the mass of the mercaptosilane monomer 1 and the mass of the unsaturated symmetric episulfide silane monomer SES-Si; the dosage of the photoinitiator is 0.1 to 1 percent of the sum of the mass of the mercaptosilane monomer and the mass of the unsaturated symmetric episulfide silane monomer SES-Si; the adding amount of the inert water absorbent is 0.5 to 1 time of the sum of the mass of the mercaptosilane monomer 1, the mass of the unsaturated symmetric episulfide silane monomer SES-Si, the mass of the mercaptosilane monomer 2 and the mass of the aromatic alkoxy silane monomer; the mol ratio of the episulfide stabilizer to the unsaturated symmetrical episulfide silane monomer SES-Si is (1.05-1.1): 1; the dosage of the catalyst is 0.2-0.8% of the sum of the mercaptosilane monomer 1, the unsaturated symmetric episulfide silane monomer SES-Si, the mercaptosilane monomer 2 and the aromatic alkoxy silane monomer.

Further, water is added dropwise in order to hydrolyze the alkoxysilane to the silanol compound and thereby facilitate the subsequent polycondensation reaction, and it is preferable that the molar addition amount of water is 1.4 to 1.6 times the molar addition amount of the mercaptosilane monomer 1, the mercaptosilane monomer 2 and the aromatic alkoxysilane monomer.

Further, after telomerization, the purification steps include neutralization after cooling, primary distillation, water washing and separation, and then the purified photocuring high-refractive index mercapto silicone oil can be obtained. Wherein, preferably, in order to remove the acid catalyst in the system, one or more of sodium carbonate, calcium carbonate, magnesium carbonate, ammonium carbonate, sodium bicarbonate, ammonium bicarbonate, magnesium bicarbonate and the like can be selected for neutralization, and prepared into a saturated solution of 50% ethanol-water, and the saturated solution is used as a water washing liquid of a water washing step for water washing for 3 times; the primary distillation refers to reduced pressure distillation at 30-40 ℃ and-0.095 MPa, and mainly distills out alcohol in the system to prevent an organic solvent layer from forming a homogeneous phase with the alcohol, so that a layering effect is difficult to achieve in a water washing process, and the yield is reduced. And (2) separating and purifying the organic solvent layer after water washing layering, wherein the separation and purification steps comprise secondary water washing layering, secondary distillation and column chromatography, the secondary water washing layering are performed by taking pure deionized water as water washing liquid and adding a demulsifier, and the demulsifier is an inert demulsifier which can be one or more of demulsifiers SP-169, BBE20601, AP-05, HA-22, HA-42, DE0712, AE8051, AE9901, AP113 and the like, and is used in an amount of 0.1-0.5 percent of the sum of the mercaptosilane monomer 1, the unsaturated symmetric episulfide silane monomer SES-Si, the mercaptosilane monomer 2, the aromatic alkoxy silane monomer and the organic solvent. The method can effectively reduce the washing time, improve the washing efficiency, accelerate the layering, improve the product purity and improve the post-treatment efficiency. The secondary distillation refers to reduced pressure distillation at 70-90 deg.C and-0.095 MPa to achieve the purpose of purification, and specifically, the solvent can be removed by rotary evaporation. The column chromatography is refined purification to obtain high-purity high-refractive index mercapto silicone oil, and the eluent can be selected from petroleum ether/ethyl acetate, methanol/chloroform, cyclohexane/toluene and the like.

The high-refractive-index mercapto silicone oil prepared by the invention contains a symmetrical episulfide group and a light-curable mercapto group, wherein the symmetrical episulfide group introduced into the structure is used for improving the refractive index of the mercapto silicone oil and simultaneously not bringing serious pungent smell, and the introduction of the mercapto group is used for realizing the rapid preparation of an organic silicon product based on a mercapto-alkene photopolymerization mechanism. In addition, the episulfide modified mercapto silicone oil can realize high refractive index and quick curing characteristics, a high refractive index silicone formula capable of being quickly cured is prepared through the formula design of a mercapto-alkene photopolymerization mechanism, and a thioether structure generated by a mercapto-alkene photopolymerized silicone material endows the silicone material with excellent toughness, refractive index, heat resistance, hydrolysis resistance, adhesion, oxidation resistance and the like.

Drawings

FIG. 1 shows that the molar ratio of mercapto silicone oil HIRS-Si01 to vinyl phenyl silicone oil is 1:1, 1.5wt.% of photoinitiator 1173 and 70mW/cm of radiation intensity at 365nm ² Testing the obtained FTIR graphs in 5 real-time under the condition;

FIG. 2 is a graph showing the double bond conversion rate of different mercapto silicone oils.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, but the technical solutions do not limit the scope of the present invention.

The invention provides a light-curable high-refractive-index mercapto silicone oil and a preparation method thereof; the technical scheme is a one-pot two-step method, firstly, a symmetrical episulfide silicon-based modified silane monomer (SES-Si) is prepared through sulfydryl-alkene photopolymerization, and then, the high-refractive-index sulfydryl silicone oil is prepared through a hydrolysis-polycondensation method. Due to the structural particularity of the mercapto silicone oil, the prepared mercapto silicone oil with high refractive index is transparent, can be quickly cured, has a high refractive index, and is stable at room temperature, good in storage stability and low in smell. In addition, the invention adopts a one-pot two-step method, has simple and convenient preparation process, high production efficiency, lower cost and no harsh reaction condition, and is easy to realize industrial production.

The detection methods of the examples and comparative examples of the present invention are:

infrared spectroscopy, elemental analysis and nuclear magnetic hydrogen spectroscopy ( ¹ H-NMR) test for structural characterization (reference: doctor's academic degree of Guangdong industry universityPaper, liu Zhu preparation and performance study of intrinsic self-repairing light-cured transparent silicone elastomer, liu Zhu, courtesy, hong Ping, rong Minzhi, zhang Ming autumn]Chinese plastics, 2020, 34 (5): 68-76), the concrete method is as follows:

(1) Fourier transform infrared spectroscopy (FTIR)

The infrared spectrometer iS obtained by adopting a Nicolet iS50 type Fourier transform infrared spectrometer manufactured by German Thermo Fisher Scientific company and performing a KBr tabletting method, wherein the scanning wavelength range iS 4000-600 cm < -1 >, the resolution ratio iS 4cm < -1 >, and the scanning frequency iS 32 times.

(2) Elemental analysis

PDMS-SH was analyzed for its C, H, O and S element content at room temperature using an organic element analyzer model EA 3000 from Euro Vector, italy.

(3) Nuclear magnetic hydrogen spectrum ( ¹ H-NMR)

Adopting Bruker AVANCE III MHz Superreducing Fourier nuclear magnetic resonance spectrometer, the measuring condition is room temperature, the solvent is deuterated chloroform (CDCl) ₃ ). And adopt ¹ The mercapto content of the prepared mercapto silicone oil with high refractive index can be tested by an H NMR internal standard method. Using dioxane as internal standard substance and CDCl as raw material at room temperature ₃ Is a solvent. Weighing a certain amount of sample and 1,4-dioxane, mixing in CDCl ₃ And (5) testing after ultrasonic treatment for 20min, and calculating the content of sulfydryl.

The photocuring conversion rate and the curing rate of the high-refractive-index UV photocuring mercapto silicone oil can be characterized and analyzed by using an RT-IR technology. KBr wafer as carrier, test range 700-4000 cm ^-1 The radiation intensity of 395nm is 70mW/cm ² The MUA-165 type UV light source is an ultraviolet radiation source with a length of 1265cm ^-1 Monitoring 1640cm using Si-Me characteristic absorption peak as internal standard ^-1 nearby-CH = CH ₂ The characteristic absorption peak (-Vi) was calculated by OMNIC 8.1 IR software as per equation 1 for-Vi conversion. (see: thesis Liu Zhu, courteous, hong Ping, rong Minzhi, zhang Ming autumn.) preparation and performance study of UV light-cured silicone resin for LED encapsulation [ J]Chinese plastics, 2020, 34 (5): 68-76)

C _t ＝(A ₀ -A _t )/A ₀ ×100％ (1)

In the formula, C _t Conversion of-Vi,%; a. The ₀ And A _t The peak area ratios before and after the irradiation time t to Vi were normalized relative to each other.

The molecular weight and the molecular weight distribution of the high-refractive-index UV photocuring mercapto silicone oil are measured by adopting a Viscotek VE112 type gel permeation chromatograph of VISCOTEK company, USA, taking chromatographic pure THF as a mobile phase, correcting a standard curve through standard polystyrene under the condition of a flow rate of 1.0mL/min, and then measuring the molecular weight and the polydispersity of the polymer. ( Reference is made to: paper, liu Zhu, courtesy, hong Ping, rong Minzhi, zhang Ming autumn preparation and performance study of UV light-cured silicone resin for LED packaging [ J ] chinese plastic, 2020, 34 (5): 68-76 )

Gardner color: testing according to GB/T22295-2008;

odor intensity: testing according to GB/T14675-93;

refractive index: testing according to GB/T6488-2008;

viscosity: testing the dynamic viscosity value at 25 ℃ according to GB/T10247-1988;

visible light transmittance: testing with UV2450 UV-visible spectrophotometer of Shimadzu corporation, japan, according to ASTM D1003-13;

storage stability: according to GB/T7123.2-2002, the storage period is obtained by taking viscosity as an index, and the storage stability is compared according to the storage period.

Example 1

Unsaturated symmetric episulfide silane monomer C ₅ H ₁₀ SiS ₂ Preparation of (theoretical: C37.04%, H6.17%), found: c37.28%, H6.42%, 10.04g,95.63wt.%, structural formula as follows:

methyl vinyl dimethoxyalkane (13.20g, 0.1mol), HSCH ₂ CH ₂ SH (4.70g, 0.05mol), toluene (452.00 g) andand p-toluenesulfonic acid (0.11 g) in N ₂ Under the protection condition, mechanically stirring for 48 hours at 80 ℃, and then adding HSCH ₂ CH ₂ SH (4.70g, 0.05mol) and p-toluenesulfonic acid (0.11 g) were mechanically stirred at 100 ℃ for 36h, brought to room temperature with NaHCO ₃ Washing with saturated water solution for 2 times, collecting oil layer, and adding anhydrous CaCl ₂ Drying, rotary steaming, and vacuum concentrating to obtain unsaturated symmetric episulfide silane monomer C ₅ H ₁₀ SiS ₂ 。

Mercaptomethylmethyldimethoxysilane (16.72g, 0.11mol), unsaturated symmetrical episulfide silane monomer C ₅ H ₁₀ SiS ₂ (16.20g, 0.1mol), toluene (33.85 g) and a photoinitiator Darocure1173 (0.06 g) were mechanically stirred for 20min, and then the maximum irradiation intensity was 80mW/cm ² Under the ultraviolet light with the wavelength range of 200-400 nm, carrying out sulfydryl-alkene click reaction for 10min, adding sulfydryl methyl dimethoxy silane (66.88g, 0.44mol) and methyl phenyl diethoxy silane (94.65g, 0.44mol), mechanically stirring for 20min, adding diethyl hydroxymethyl malonate (23.10g, 0.105mol) and 37% concentrated hydrochloric acid (0.58 g), dropwise adding deionized water (24.95g, 1.39mol) at 65 ℃, carrying out hydrolysis-polycondensation reaction for 16h after dropwise adding is finished, and adding an end-capping agent ^H MM ^H (4.05g, 0.025mol) and a 5A activated molecular sieve (115.41 g) are heated to 85 ℃ for balanced telomerization for 3h, the temperature is reduced, 50% ethanol-water sodium carbonate saturated solution is added for washing for 3 times, demulsifier AP-05 (0.23 g) is added for shaking up and layering, an organic layer is taken and distilled under reduced pressure at 30-40 ℃ and 0.095MPa for 30min, secondary distilled water is added for washing, demulsifier AP-05 (0.23 g) is added for shaking up and standing for layering, an oil layer is taken and distilled under reduced pressure at 70-90 ℃ and 0.095MPa for 60min, and the oil layer is purified by column chromatography (petroleum ether/ethyl acetate =20/1, mass ratio) to obtain high-refractive index mercapto silicone oil (HIRS-Si 01), 118.92g, and the yield is 90.93%.

For the prepared HIRS-Si01 (theoretical formula: C) ₁₇₆ H ₃₀₂ Si ₄₂ S ₂₈ O ₃₇ ) Performing elemental analysis, infrared analysis and ¹ H-NMR analysis.

Elemental analysis: found: c41.88%, H6.10%, O11.32%, S17.91%

IR(cm ^-1 )：3010～3120(s，υ _C-H ，-C ₆ H ₅ )，2950～2970(s，υ _C-H ，-CH ₃ )，2830～2860(s，υ _C-H ，-CH ₂ -)，2565(s，υ _S-H ，-SH)，2150(m，υ _Si-H Si-H), 1595, 1580 and 1480 (s, upsilon) _C-C ，-C ₆ H ₅ )，1405(m，δ _Si-C ，Si-CH ₃ ) 1350 and 1305 (m, v) _C-H ，-CH ₂ -)，1265(s，δ _Si-C ，Si-CH ₃ )，1230(m，υ _Si -S，-S(CH ₃ )SiS-)，1150(m，υ _S-C S-C-S), 1010 and 1050 (S, upsilon) _Si-O ，Si-O-Si)，810(s，δ _S-H ，-SH)，700～800(s，υ _Si-C ，Si-CH ₃ )。

¹ H-NMR(δppm，CDCl ₃ ，400MHz)：7.35～7.55(m，5H，Si-Ph)，4.75(s，1H，Si-H)，2.93(s，4H，

)，2.78(m，2H，-SC ₂ HCH ₂ -)，1.33(m，2H，-SiCH ₂ S-)，1.20(s，1H，-SH)，0.52(m，2H，-SCH ₂ C ₂ H-)，0.13(s，3H，

)，-0.15～0.21(m，3H，Si-CH ₃ )。

Example 2

Unsaturated symmetric episulfide silane monomer C ₉ H ₁₀ SiS ₂ Preparation of (theoretical: C51.43%, H4.76%), found: c51.83%, H4.42%, 22.95g,93.47wt.%, structural formula:

methyl vinyl diethoxy alkane (16.00g, 0.1mol),

(8.50g, 0.06mol), ethyl acetate (612.50 g) and p-toluenesulfonic acid (0.196 g) in N ₂ Mechanically stirring at 100 deg.C for 36 hr under protection, and adding

(8.50g, 0.06mol) and p-toluenesulfonic acid (0.196 g), mechanically stirred at 80 ℃ for 42h, brought to room temperature with NaHCO ₃ Washing with saturated water solution for 2 times, collecting oil layer, and removing anhydrous MgSO ₄ Drying, rotary steaming, and vacuum concentrating to obtain unsaturated symmetric episulfide silane monomer C ₉ H ₁₀ SiS ₂

Mercaptopropyl methyl dimethoxy silane (63.12g, 0.35mol), unsaturated symmetrical episulfide silane monomer C ₉ H ₁₀ SiS ₂ (63.00g, 0.3mol), benzene (252.24 g) and photoinitiator 2,4,6-trimethylbenzoylphenylphosphonic acid ethyl ester TPO-L (0.63 g) were mechanically stirred for 30min at a maximum irradiation intensity of 100mW/cm ² Under the ultraviolet light with the wavelength range of 200-400 nm, carrying out sulfydryl-alkene light click reaction for 10min, adding mercaptopropyl methyl dimethoxy silane (90.00g, 0.50mol) and diphenyl diethoxy silane (53.07g, 0.195mol), mechanically stirring for 20min, adding 2-methyl-2-acrylic acid-1,10-decanediol (102.30g, 0.32mol) and trifluoromethanesulfonic acid (0.54 g), dropwise adding deionized water (30.10g, 1.672mol) at 75 ℃, carrying out hydrolysis-polycondensation reaction for 14h after dropwise addition, adding end capping agents MM (0.81g, 0.0.3252 mol) and magnesium sulfate (3252 zxft) and raising the temperature to 80 ℃ for equilibrium and telomerization for 5h, cooling, adding 50% ethanol-water sodium carbonate saturated solution, washing for 3 times, adding a demulsifier SP-169 (1.56 g), shaking uniformly and layering, taking an organic layer, standing for 30-3240 ℃, distilling at a reduced pressure of 0.095 min, and obtaining a high yield of distilled water (355-35 MPa), shaking for 5MPa, and purifying by chromatography under the distilled water (30-3432 MPa), and the distilled water ratio of SP-3525 MPa).

For the prepared HIRS-Si02 (theoretical formula: C) ₁₆₄₂ H ₂₅₉₈ Si ₂₆₀ S ₂₂₀ O ₁₉₉ ) Performing elemental analysis, infrared analysis and ¹ H-NMR analysis.

Elemental analysis: found: 49.68% of C, 6.72% of H, 7.84% of O and 17.65% of S

IR(cm ^-1 )：3000～3100(s，υ _C-H ，-C ₆ H ₅ )，2942～2958(s，υ _C-H ，-CH ₃ )，2865～2890(s，υ _C-H ，-CH ₂ -)，2560(s，υ _S-H -SH), 1635, 1560, and 1460 (s, v) _C-C ，-C ₆ H ₅ )，1410(m，δ _Si-C ，Si-CH ₃ ) 1360 and 1320 (m, v) _C-H ，-CH ₂ -)，1260(s，δ _Si-C ，Si-CH ₃ )，1215(m，υ _Si -S，-S(CH ₃ )SiS-)，1180(m，υ _S-C ，-S-C ₆ H ₅ -S-), 1020 and 1080 (S, upsilon) _Si-O ，Si-O-Si)，815(s，δ _S-H ，-SH)，700～800(s，υ _Si-C ，Si-CH ₃ )。

¹ H-NMR(δppm，CDCl ₃ ，400MHz)：7.98～8.12(s，4H，

)，7.40～7.65(m，5H，Si-Ph)，2.83(m，2H，-SC ₂ HCH ₂ CH ₂ -)，2.64(m，2H，HSC ₂ HCH ₂ CH ₂ -)，1.83(m，2H，-S ₂ CHCH ₂ -)，1.67(m，2H，-SCH ₂ C ₂ HCH ₂ -)，1.58(m，2H，HSCH ₂ C ₂ HCH ₂ -)，1.16(s，1H，-SH)，1.33(m，2H，-SC ₂ HCH ₂ -)，0.87(m，2H，-SCH ₂ C ₂ H-)，0.63(m，2H，-SCH ₂ CH ₂ C ₂ H-)，0.52(m，2H，HSCH ₂ CH ₂ C ₂ H-)，0.24(s，3H，

)，-0.20～0.15(m，3H，Si-CH ₃ )。

Example 3

Unsaturated symmetrical episulfide silane monomer C ₁₃ H ₁₂ SiS ₂ Preparation of (1) (theoretical value: C60.00%, H4.62%), found: c59.83%, H4.86%, 24.33g,95.08wt.%, structural formula:

methyl vinyl diethoxy alkane (16.03g, 0.10mol),

(9.62g, 0.05mol), diethyl ether (768.00 g), and trifluoromethanesulfonic acid (0.26 g) in N ₂ Mechanically stirring at 90 deg.C for 40 hr under protection, and adding

(9.62g, 0.05mol) and trifluoromethanesulfonic acid (0.26 g), and further at 90 deg.C, mechanically stirred for 36h, cooled to room temperature, treated with NaHCO ₃ Washing with saturated water solution for 2 times, collecting oil layer, and adding anhydrous Na ₂ SO ₄ Drying, rotary steaming, and vacuum concentrating to obtain unsaturated symmetric episulfide silicane C ₁₃ H ₁₂ SiS ₂ 。

Mercaptopropyl methyldiethoxysilane (45.84g, 0.22mol), unsaturated symmetrical episulfide silane monomer C ₁₃ H ₁₂ SiS ₂ (52.00g, 0.20mol), chloroform (197.74 g) and photoinitiator 2,4,6-trimethylbenzoyl-diphenylphosphine oxide TPO (0.59 g) were mechanically stirred for 20min, and then the maximum irradiation intensity was 125mW/cm ² Under the ultraviolet light with the wavelength range of 200-400 nm, mercapto-alkene light click reaction is carried out for 8min, mercaptopropyl methyldimethoxysilane (75.60g, 0.42mol) and methylphenyldiethoxysilane (75.72g, 0.36mol) are added, mechanical stirring is carried out for 30min, diethylene glycol bis (stearate) (153.37g, 0.24mol) and concentrated sulfuric acid (1.25 g) are added, deionized water (27.00g, 1.50mol) is dripped at 70 ℃, and hydrolysis-polycondensation is carried out after dripping is finishedAfter 15h of reaction, adding an end-capping reagent MM (3.24g, 0.02mol) and anhydrous calcium sulfate (200.15 g), heating to 90 ℃ for balanced telomerization for 2h, cooling to room temperature, adding a 50% ethanol-water sodium carbonate saturated solution, washing for 3 times, adding a demulsifier BBE20601 (0.53 g), shaking uniformly, standing for layering, taking an organic layer, distilling under reduced pressure at 30-40 ℃ and 0.095MPa for 30min, washing with distilled water for the second time, adding a demulsifier HA-22 (1.05 g) for layering, taking an oil layer, distilling under reduced pressure at 70-90 ℃ and 0.095MPa for 60min, and purifying by column chromatography (cyclohexane/toluene =20/1, mass ratio) to obtain high-refractive index mercapto-silicone oil (HIRS-Si 03), 169.25g and 89.06 wt%.

For the prepared HIRS-Si03 (theoretical formula: C) ₃₈₂ H ₅₈₂ Si ₆₀ S ₅₀ O ₄₈ ) Performing elemental analysis, infrared analysis and ¹ H-NMR analysis.

Elemental analysis: found: 49.71 percent of C, 6.18 percent of H, 8.51 percent of O and 17.25 percent of S

IR(cm ^-1 )：3105～3225(m，υ _C-H ，-S-C ₁₀ H ₆ -S-)，3020～3090(s，υ _C-H ，-C ₆ H ₅ )，2952～2965(s，υ _C-H ，-CH ₃ )，2882～2910(s，υ _C-H ，-CH ₂ -)，2570(s，υ _S-H -SH), 1630, 1520 and 1435 (s, υ) _C-C ，-C ₆ H ₅ )，1400(m，δ _Si-C ，Si-CH ₃ ) 1340 and 1315 (m, upsilon) _C-H ，-CH ₂ -)，1265(s，δ _Si-C ，Si-CH ₃ )，1225(m，υ _Si-S ，-S(CH ₃ )SiS-)，1160(m，υ _S-C ，-S-C ₁₀ H ₆ -S-), 1010 and 1080 (S, upsilon) _Si-O ，Si-O-Si)，810(s，δ _S-H ，-SH)，720～800(s，υ _Si-C ，Si-CH ₃ )。

¹ H-NMR(δppm，CDCl ₃ ，400MHz)：7.20～8.20(m，11H，

And overlap of aromatic rings in Si-Ph), 2.94 (m, 2H, -SC) ₂ HCH ₂ CH ₂ -)，2.72(m，2H，HSC ₂ HCH ₂ CH ₂ -)，1.94(m，2H，-S ₂ CHCH ₂ -)，1.67(m，2H，-SCH ₂ C ₂ HCH ₂ -)，1.67(m，2H，HSCH ₂ C ₂ HCH ₂ -)，1.21(s，1H，-SH)，1.44(m，2H，-SC ₂ HCH ₂ -)，0.91(m，2H，-SCH ₂ ₂ CH-)，0.63(m，2H，-SCH ₂ CH ₂ C ₂ H-)，0.50(m，2H，HSCH ₂ CH ₂ C ₂ H-)，0.29(s，3H，

middle-CH ₃ )，-0.25～0.15(m，3H，Si-CH ₃ )。

Example 4

Unsaturated symmetric episulfide silane monomer C ₁₀ H ₁₆ SiS ₂ Preparation of (theoretical value: C52.63%, H7.02%), found: c52.51%, H7.39%, 19.92g,93.83wt.%, structural formula as follows:

methyl vinyl dimethoxyalkane (13.22g, 0.1mol),

(8.02g, 0.05mol), N-hexane (530.00 g), and p-toluenesulfonic acid (0.42 g) in N ₂ Mechanically stirring at 80 deg.C for 45 hr under protection, and adding

(8.02g, 0.05mol) and p-toluenesulfonic acid (0.42 g), further mechanically stirring at 80 ℃ for 40h, cooling to room temperature, and reacting with NaHCO ₃ Washing with saturated water solution for 2 times, collecting oil layer, and removing anhydrous MgSO ₄ Drying, rotary steaming, and vacuum concentrating to obtain unsaturated symmetric episulfide silane C ₁₀ H ₁₆ SiS ₂

Mercaptomethyldiethoxysilane (10.82g, 0.06mol), unsaturated symmetrical episulfide silane monomer C ₁₀ H ₁₆ SiS ₂ (11.40g, 0.05mol), cyclohexane (45.62 g) and photoinitiator 2-hydroxy-4- (2-hydroxyethoxy) -2-methylpropiophenone (Darocure 2959) (0.22 g) were mechanically stirred for 10min, and then irradiated at a maximum intensity of 150mW/cm ² Under the ultraviolet light with the wavelength range of 200-400 nm, carrying out sulfydryl-alkene light click reaction for 5min, then adding mercaptopropyl methyldimethoxysilane (45.08g, 0.25mol) and diphenyldimethoxysilane (164.70g, 0.675mol), mechanically stirring for 20min, then adding dibutyl glutarate (13.30g, 0.054mol) and concentrated hydrochloric acid (0.93 g), dripping deionized water (24.82g, 1.38mol) at 80 ℃, carrying out hydrolysis-polycondensation reaction for 13h after dripping is finished, adding a blocking agent ^H MM ^H (2.02g, 0.0125 mol) and anhydrous calcium chloride (139.20 g), heating to 85 ℃, carrying out equilibrium telomerization for 3 hours, cooling to room temperature, adding 50% ethanol-water ammonium bicarbonate saturated solution, washing for 3 times, adding a demulsifier HA-42 (1.41 g), shaking uniformly, standing for layering, taking an organic layer, distilling under reduced pressure at 30-40 ℃ and-0.095 MPa for 30 minutes, washing with distilled water for the second time, adding a demulsifier AP113 (0.28 g) for layering, taking an oil layer, distilling under reduced pressure at 70-90 ℃ and-0.095 MPa for 60 minutes, purifying by column chromatography (petroleum ether/ethyl acetate =20/1, mass ratio) to obtain high-refractive index mercapto-silicone oil (HIRS-Si 04), 174.78g, and the yield of 92.49wt.%.

For the prepared HIRS-Si04 (theoretical formula: C) ₇₄₄ H ₈₄₂ Si ₈₄ S ₃₂ O ₇₉ ) Performing elemental analysis, infrared analysis and ¹ H-NMR analysis.

Elemental analysis: found: c62.89%, H5.51%, O8.39%, S7.03%

IR(cm ^-1 )：3050～3080(s，υ _C-H ，-C ₆ H ₅ )，2948～2972(s，υ _C-H ，-CH ₃ )，2895～2920(s，υ _C-H ，-CH ₂ -)，2865～2880(s，υ _C-H ，

)，2560(s，υ _S-H ，-SH)，2160(m，υ _Si-H ，Si-H)，1635，1530，1410(s，υ _C-C ，-C ₆ H ₅ )，1410(m，δ _Si-C ，Si-CH ₃ ) 1355 and 1320 (m, upsilon) _C-H ，-CH ₂ -)，1260(s，δ _Si-C ，Si-CH ₃ )，1230(m，υ _Si-S ，-S(CH ₃ ) SiS-), 1040 and 1100 (s, upsilon) _Si-O ，Si-O-Si)，820(s，δ _S-H ，-SH)，700～780(s，υ _Si-C ，Si-CH ₃ )。

¹ H-NMR(δppm，CDCl ₃ ，400MHz)：7.40～7.62(m，5H，Si-Ph)，4.83(m，1H，Si-H)，2.81(m，2H，HSC ₂ HCH ₂ CH ₂ -)，2.65(m，2H，＝CH-S(CH ₃ )SiS-CH＝)，2.43(m，2H，-SC ₂ HCH ₂ Si-), 2.13 and 1.88 (m, 2H,

)，1.76(m，2H，Si-C ₂ H-S-)，1.70(m，2H，

)，1.68(m，2H，HSCH ₂ C ₂ HCH ₂ -), 1.56 and 1.38 (m, 4H,

)，1.24(s，1H，-SH)，0.53(m，2H，-SCH ₂ CH ₂ C ₂ H-)，0.95(d，2H，-SCH ₂ C ₂ HSi-)0.19(s，3H，

)，-0.25～0.10(m，3H，Si-CH ₃ )。

example 5

Unsaturated symmetrical episulfide silane monomer C ₁₁ H ₂₂ SiS ₄ Preparation of (1) (theoretical value: C42.58%, H7.10%), found: c42.81%, H6.88%, 30.74g,93.71wt.%, structural formula as follows:

methyl (allyl) dimethoxyalkane (14.6g, 0.10mol),

(11.40g, 0.05mol), isopropanol (650.00 g) and p-toluenesulphonic acid (0.2090 g) in N ₂ Mechanically stirring at 90 deg.C for 40 hr under protection, and adding

(11.40g, 0.05mol) and p-toluenesulfonic acid (0.2090 g), further mechanically stirred at 100 ℃ for 45h, cooled to room temperature, and treated with NaHCO ₃ Washing with saturated water solution for 2 times, collecting oil layer, and removing anhydrous MgSO ₄ Drying, rotary steaming, and vacuum concentrating to obtain unsaturated symmetric episulfide silane C ₁₁ H ₂₂ SiS ₄ 。

Mercaptopropyl methyldimethoxysilane (29.76g, 0.165mol), unsaturated symmetrical episulfide silane monomer C ₁₁ H ₂₂ SiS ₄ (46.5g, 0.15mol), toluene (175.40 g) and photoinitiator 1-hydroxy-cyclohexyl-benzophenone (Irgacure 184) (0.15 g) were mechanically stirred for 20 min' and then irradiated at a maximum irradiation intensity of 120mW/cm ² Under the ultraviolet light with the wavelength range of 200-400 nm, carrying out sulfydryl-alkene light click reaction for 10min, then adding mercaptopropyl methyldimethoxysilane (108.20g, 0.60mol) and methylphenyldimethoxysilane (43.74g, 0.24mol), mechanically stirring for 15min, then adding diisopropyl succinate (34.38g, 0.17mol) and concentrated hydrochloric acid (1.40 g), at 70 ℃, dropwise adding deionized water (25.33g, 1.41mol), after dropwise adding, carrying out hydrolysis-polycondensation reaction for 15h, adding end capping agent trimethylmethoxysilane (1.04g, 0.01mol) and 5A activated molecular sieve (136.92 g), heating to 90 ℃ for equilibrium and polymerization for 4h, cooling to room temperature, adding 50% ethanol-water ammonium carbonate saturated solution, washing for 3 times, adding demulsifier 9901 (0.40 AE) for uniform shaking and standing for layering, taking an organic layer at 30-40 ℃, keeping the temperature to 0.095MPa, then carrying out reduced pressure distillation for 30min, adding distilled water and carrying out secondary distilled water and adding demulsifier 9901 (0.40 AE) for secondary distillationDE0712 (0.50 g) as demulsifier for layering, vacuum distilling the oil layer at 70-90 deg.c and-0.095 MPa for 90min, and purifying by column chromatography (methanol/chloroform =25/1, mass ratio) to obtain high refractive index mercapto-silicone oil (HIRS-Si 05), 167.08g, with a yield of 91.83wt.%.

For the prepared HIRS-Si05 (theoretical formula: C) ₁₂₇₂ H ₂₅₆₂ Si ₂₀₀ S ₂₇₀ O ₁₉₉ ) Performing elemental analysis, infrared analysis and ¹ H-NMR analysis.

Elemental analysis: found: c43.51%, H7.44%, O9.09%, S24.27%

IR(cm ^-1 )：3065～3010(s，υ _C-H ，-C ₆ H ₅ )，2970～2995(s，υ _C-H ，-CH ₃ )，2910～2955(s，υ _C-H ，-CH ₂ -)，2570(s，υ _S-H ，-SH)，1640，1510，1425(s，υ _C-C ，-C ₆ H ₅ )，1405(m，δ _Si-C ，Si-CH ₃ ) 1360 and 1305 (m, v) _C-H ，-CH ₂ -)，1265(s，δ _Si-C ，Si-CH ₃ )，1250(m，υ _Si-S ，-S(CH ₃ ) SiS-), 1020 and 1150 (s, ups) _Si-O ，Si-O-Si)，850(s，δ _S-H ，-SH)，720～760(s，υ _Si-C ，Si-CH ₃ )。

¹ H-NMR(δppm，CDCl ₃ ，400MHz)：7.50～7.75(m，5H，Si-Ph)，3.05～3.11(m，4H，

)，2.92(m，2H，HSC ₂ HCH ₂ CH ₂ -)，2.68～2.76(m，4H，

)，2.38～2.45(m，8H，

)，2.11(m，2H，

)，1.50～1.65(m，2H，Si-CH ₂ C ₂ H-)，1.32(s，1H，-SH)，0.60～0.65(m，2H，Si-CH ₂ -)，-0.10～0.25(m，3H，Si-CH ₃ )。

Comparative example 1:

mercaptopropyl methyldimethoxysilane (29.76g, 0.165mol), unsaturated symmetrical episulfide silane monomer C ₁₁ H ₂₂ SiS ₄ (46.5g, 0.15mol), toluene (175.40 g) and photoinitiator 1-hydroxy-cyclohexyl-benzophenone (Irgacure 184) (0.15 g) were mechanically stirred for 20min, then irradiated at a maximum irradiation intensity of 120mW/cm ² Under the ultraviolet light with the wavelength range of 200-400 nm, carrying out sulfydryl-alkene light click reaction for 10min, adding mercaptopropyl methyldimethoxysilane (108.20g, 0.60mol) and methylphenyldimethoxysilane (43.74g, 0.24mol), mechanically stirring for 15min, adding concentrated hydrochloric acid (1.40 g), dropwise adding deionized water (25.33g, 1.41mol) at 70 ℃, carrying out hydrolysis-polycondensation reaction for 15h after dropwise adding is finished, adding end-capping agent trimethylmethoxysilane (1.04g, 0.01mol) and 5A activated molecular sieve (136.92 g), heating to 90 ℃, carrying out equilibrium polymerization for 4h, cooling to room temperature, adding 50% ethanol-water ammonium carbonate saturated solution, washing for 3 times, adding a demulsifier AE9901 (0.40 g), shaking uniformly, standing for layering, taking an organic layer, distilling at 30-40 ℃ and-0.095 MPa under reduced pressure for 30min, washing with secondary distilled water, adding a demulsifier DE0712 (0.50 g) for layering, taking an oil layer, distilling at 70-90 ℃ and-0.095 MPa under reduced pressure for 90min, and purifying by column chromatography (methanol/chloroform =25/1, mass ratio) to obtain high-refractive index mercapto-silicone oil (P-HIRS-Si 01), 152.39g, with the yield of 83.76wt.%.

Performing elemental analysis and infrared analysis on the prepared P-HIRS-Si01 ¹ H-NMR analysis.

Elemental analysis: found: c51.77%, H9.06%, O13.53%, S15.37%, equivalent to that of example 5 (Found: C43.51%, H7.44%, O9.09%, S24.27%, theoretical value (theoretical formula: C) ₁₂₇₂ H ₂₅₆₂ Si ₂₀₀ S ₂₇₀ O ₁₉₉ ): c43.30%, H7.27%, O9.03%, S24.51%) did not.

IR(cm ^-1 )：3410～34675(s，υ _OH ，-OH)3060～3120(s，υ _C-H ，-C ₆ H ₅ )，2950～2975(s，υ _C-H ，-CH ₃ )，2900～2935(s，υ _C-H ，-CH ₂ -)，2565(s，υ _S-H ，-SH)，1635，1520，1410(s，υ _C-C ，-C ₆ H ₅ )，1400(m，δ _Si-C ，Si-CH ₃ ) 1340, and 1295 (m, upsilon) _C-H ，-CH ₂ -)，1258(s，δ _Si-C ，Si-CH ₃ ) 1010 and 1080 (s, v) _Si-O ，Si-O-Si)，940～980(s，δ _S-C ，S-C-S)，860(s，δ _S-H ，-SH)，720～760(s，υ _Si-C ，Si-CH ₃ )。

¹ H-NMR(δppm，CDCl ₃ ，400MHz)：7.35～7.46(m，5H，Si-Ph)，2.97(s，2H，Si-C ₂ HCH ₂ S-)，2.85(m，2H，HSC ₂ HCH ₂ CH ₂ -)，2.75(s，2H，Si-CH ₂ C ₂ HS-)，2.43(d，2H，S-CH ₂ -)，1.55～1.77(m，2H，Si-CH ₂ C ₂ H-)，1.32(s，1H，-SH)0.60～0.67(m，2H，Si-CH ₂ -)，-0.10～0.25(m，3H，Si-CH ₃ )。

Comparative example 2:

mercaptopropyl methyldimethoxysilane (29.76g, 0.165mol), unsaturated symmetrical episulfide silane monomer C ₁₁ H ₂₂ SiS ₄ (46.5g, 0.15mol), toluene (175.40 g) and photoinitiator 1-hydroxy-cyclohexyl-benzophenone (Irgacure 184) (0.15 g) were mechanically stirred for 20 min' and then irradiated at a maximum irradiation intensity of 120mW/cm ² Under the ultraviolet light with the wavelength range of 200-400 nm, carrying out sulfydryl-alkene light click reaction for 10min, then adding mercaptopropyl methyl dimethoxy silane (108.20g, 0.60mol) and methyl phenyl dimethoxy silane (43.74g, 0.24mol), mechanically stirring for 15min, then adding diisopropyl succinate (34.38g, 0.17mol) and concentrated hydrochloric acid (1.40 g), dropwise adding deionized water (25.33g, 1.41mol) at 70 ℃, carrying out hydrolysis-polycondensation reaction for 15h after dropwise adding is finished, adding end-capping agent trimethyl methoxy silane (1.04g, 0.01mol) and 5A activated molecular sieve (136.92 g), heating to 90 ℃, carrying out equilibrium polymerization for 4h, cooling, and carrying outAnd (2) cooling to room temperature, adding 50% ethanol-water ammonium carbonate saturated solution, washing for 3 times, standing for layering, distilling an organic layer at 30-40 ℃ and under the reduced pressure of-0.095 MPa for 30min, washing with secondary distilled water for layering, distilling an oil layer at 70-90 ℃ and under the reduced pressure of-0.095 MPa for 90min, and purifying by column chromatography (methanol/chloroform =25/1, mass ratio) to obtain high-refractive-index mercapto-silicone oil (P-HIRS-Si 02), 105.93g and 58.22 wt%.

For the prepared P-HIRS-Si02 (theoretical formula: C) ₁₂₇₂ H ₂₅₆₂ Si ₂₀₀ S ₂₇₀ O ₁₉₉ ) Performing elemental analysis, infrared analysis and ¹ H-NMR analysis.

Elemental analysis: found: c43.66%, H7.32%, O8.91%, S24.39%, comparable to example 5 (Found: C43.51%, H7.44%, O9.09%, S24.27%, theoretical value (theoretical formula: C: S24.27%) ₁₂₇₂ H ₂₅₆₂ Si ₂₀₀ S ₂₇₀ O ₁₉₉ ): c43.30%, H7.27%, O9.03%, S24.51%) meet.

IR(cm ^-1 )：3050～3000(s，υ _C-H ，-C ₆ H ₅ )，2966～2990(s，υ _C-H ，-CH ₃ )，2925～2968(s，υ _C-H ，-CH ₂ -)，2565(s，υ _S-H ，-SH)，1645，1515，1428(s，υ _C-C ，-C ₆ H ₅ )，1411(m，δ _Si-C ，Si-CH ₃ ) 1366 and 1311 (m, upsilon) _C-H ，-CH ₂ -)，1267(s，δ _Si-C ，Si-CH ₃ )，1243(m，υ _Si-S ，-S(CH ₃ ) SiS-), 1010 and 1090 (s, upsilon) _Si-O ，Si-O-Si)，838(s，δ _S-H ，-SH)，710～750(s，υ _Si-C ，Si-CH ₃ )。

¹ H-NMR(δppm，CDCl ₃ ，400MHz)：7.55～7.77(m，5H，Si-Ph)，3.08～3.16(m，4H，

)，2.95(m，2H，HSC ₂ HCH ₂ CH ₂ -)，2.60～2.75(m，4H，

)，2.30～2.45(m，8H，

)，2.06(m，2H，

)，1.43～1.61(m，2H，Si-CH ₂ C ₂ H-)，1.28(s，1H，-SH)，0.57～0.62(m，2H，Si-CH ₂ -)，-0.15～0.31(m，3H，Si-CH ₃ )。

Result detection

The relevant performances of the mercapto silicone oils prepared in the examples and the comparative examples are tested, and the test results are shown in the following table 1:

TABLE 1

As can be seen from Table 1, the UV-curable episulfide-modified high-refractive-index mercapto silicone oil prepared by the invention is a colorless transparent viscous substance, has low smell (Gardner chroma is less than 2), visible light transmittance of more than 94 percent, mercapto content of 0.10-0.50 mol/100g, uniform molecular weight distribution, high refractive index, moderate viscosity and high storage stability. In addition, the aliphatic dibasic ester compound can effectively stabilize the stability of the episulfide structure in the episulfide-modified high-refractive-index mercapto silicone oil, reduce the risk of ring opening and reduce the odor problem of the prepared episulfide-modified high-refractive-index mercapto silicone oil. It can also be seen that the addition of the inert demulsifier can effectively shorten the aqueous layering time, reduce the production cost and improve the preparation rate and yield. Can be applied to photo-LED, optical fiber conduction, optical lenses, optical coatings and other optical polymers. In addition, the thiol-ene photopolymerization can be used for preparing organic silicon polymer materials or coatings rapidly, and the organic silicon polymer materials or coatings have wide application prospects in LED packaging, release agents, pressure-sensitive adhesives and optical protection.

In order to research the photo-crosslinking behavior of the prepared mercapto silicone oil, the photopolymerization rate and the conversion rate of the monomer are characterized by real-time infrared rays. Fig. 1 shows that mercapto silicone oil HIRS-Si01 and vinyl phenyl silicone oil (Vi mass fraction 2.00wt.%,25 ℃ refractive index n:1.53, 25 ℃ viscosity 2000cSt, industrial grade, purity not less than 99wt.%, guangzhou double peach fine chemical limited) have a mercapto group to vinyl group molar ratio of 1:1, 1.5wt.% of photoinitiator 1173 and 70mW/cm of radiation intensity at 365nm ² FTIR graphs at 5 real time obtained by testing under the condition that (the MUA-165 type ultraviolet radiation light source is a UV radiation light source); FIG. 2 is a graph showing the double bond conversion of different mercapto silicone oils prepared.

As can be seen from fig. 1 and 2: mercapto silicone oil and vinyl silicone oil, under the irradiation of photoinitiator 1173 and UV light, 1640cm ^-1 The peak intensity and area of the double bond characteristic peak near the point are gradually reduced, after 9.3s, the peak intensity and the peak area are basically zero, which shows that the rapid crosslinking of the sulfydryl-alkene photopolymerization is realized, the complete curing is basically achieved within about 10s, and the conversion rate can reach more than 90%. Therefore, the mercapto silicone oil with high refractive index prepared by the invention has excellent optical activity and can be used for preparing organosilicon functional materials rapidly under ultraviolet light.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention.

Claims

1. A transparent light-curable high-refractive-index mercapto silicone oil has the following structural formula:

wherein R is ₁ 、R ₂ And R ₃ The same or different hydrogen groups and alkyl groups with 2 to 10 carbon atoms;R ₄ and R ₅ Is a monovalent hydrocarbon group free of aliphatic unsaturation or a phenyl group and contains at least one phenyl group; r ₆ Has the structure of- (CH) ₂ ) _e S-CH ₂ CH ₂ R ₀ Wherein e is a positive integer of 1 to 3, R ₀ Is a symmetric episulfide heterocyclic silicon-based group and has n sulfur atoms, and n is an integral multiple of 2; r ₇ Has the structure of- (CH) ₂ ) _f SH and f are positive integers of 1-3;

a, b, c and d are numbers which are more than 0 and less than 1, and c + d is more than or equal to 0.3 and less than or equal to 0.8,0 and more than or equal to c and less than or equal to 0.3, a + b + c + d =1;

R ₀ is a symmetric episulfide heterocyclic silicon-based group, the structure of which is selected from:

one or more of them.

2. A transparent photocurable high refractive index mercapto silicone oil according to claim 1, wherein: the prepared mercapto-silicone oil is colorless transparent oil, has no pungent smell, and has dynamic viscosity of 100-50000 mPa.s at 25 deg.c, refractive index of 1.46-1.70 at 25 deg.c, visible light transmittance not lower than 98% and mercapto content of 0.15-0.85 mol/100g.

3. A method for producing a transparent photocurable high refractive index mercapto silicone oil according to any one of claims 1-2, comprising: mechanically pre-stirring mercaptosilane monomer 1, unsaturated symmetric episulfide silane monomer SES-Si, organic solvent and photoinitiator in certain proportion to obtain the final product with maximum irradiation intensity of 70-150mW/cm ² Under the ultraviolet light with the wavelength range of 200-400 nm, carrying out sulfydryl-alkene light click reaction for 5-10 min, adding a certain amount of sulfydryl silane monomer 2 and aromatic alkoxy silane monomer, mechanically stirring and mixing uniformly, adding a certain amount of episulfide stabilizer and catalyst, dripping a certain proportion of deionized water at 60-80 ℃, after finishing dripping the deionized water, carrying out hydrolysis-polycondensation reaction for 12-16 h at 60-80 ℃, adding a capping agent and an inert water absorbent at 80-90 ℃, carrying out telomerization for 2-5 h to obtain sulfydryl silicone oil with a certain viscosity, and purifying to obtain the light-curable high-refractive-index sulfydryl silicone oil;

the mercaptosilane monomers 1 and 2 are one or more of mercaptopropyl methyldimethoxysilane, mercaptopropyl methyldiethoxysilane, mercaptomethylmethyldimethoxysilane and mercaptomethylmethyldiethoxysilane; the structural formula of the unsaturated symmetric episulfide silane monomer SES-Si can be selected from any structural formula as follows:

R ₀ is an alkenyl group of 2 to 3 carbon atoms; r ¹ Is methyl; c _m 、C _n And C _x Is 0 to 1 methylene group.

4. The process for preparing a transparent photocurable high-refractive index mercapto silicone oil as set forth in claim 3, wherein: the organic solvent is one or more of toluene, benzene, chloroform, dichloromethane, pentane, cyclohexane, normal hexane, carbon tetrachloride, dichloroethane and trichloroethane.

5. The method for producing a transparent photocurable high-refractive index mercapto silicone oil according to claim 3, wherein: the photoinitiator includes benzoin, benzil, alpha-hydroxyalkyl benzophenones, alpha-amine alkyl benzophenones, acyl phosphine oxides, benzophenones, and heterocyclic arones.

6.The method for producing a transparent photocurable high-refractive index mercapto silicone oil according to claim 3, wherein: the structural formula of the aromatic alkoxy silane monomer is as follows: r ₈ R ₉ SiX ₂ X is alkoxy, R ₈ And R ₉ Is a monovalent hydrocarbon group free of aliphatic unsaturation or a phenyl group and contains at least one phenyl group.

7. The process for preparing a transparent photocurable high-refractive index mercapto silicone oil as set forth in claim 3, wherein: the inert water absorbent comprises one or more of magnesium sulfate, calcium sulfate, activated molecular sieve, anhydrous calcium chloride and anhydrous magnesium chloride.

8. The method for producing a transparent photocurable high-refractive index mercapto silicone oil according to claim 3, wherein:

the episulfide stabilizer comprises one or more of diethyl dihydroxymethylmalonate, diethyl D- (-) -tartrate, 2-methyl-2-acrylic acid-1,10-decanediol, ethylene distearate, diethylene glycol distearate, dipropylene glycol diacrylate, 2-methyl-2-acrylic acid-1,10-decanediol, lauryl acrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol diacrylate, 1,3-nonanediol acetate, dipropyl malonate, dibutyl adipate, dibutyl glutarate, diethylene glycol dipropyl ester, di-n-propyl succinate, dioctyl malonate, dimethyl adipate, diisopropyl succinate, dimethyl pimelate, dibutyl malonate, dibutyl glutarate and diethylene glycol dipropionate.

9. The process for preparing a transparent photocurable high-refractive index mercapto silicone oil as set forth in claim 3, wherein: the catalyst comprises one or more of concentrated sulfuric acid with the mass fraction of 98%, concentrated hydrochloric acid with the mass fraction of 37%, trifluoromethanesulfonic acid or strongly acidic cation resin.

10. Process for preparing a transparent photocurable high refractive index mercapto silicone oil according to claim 3The preparation method is characterized by comprising the following steps: the end-capping agent comprises a hydrocarbyl silane end-capping agent or a hydrosilane end-capping agent, and the hydrocarbyl silane end-capping agent is one or more of hexamethyldisiloxane, trimethylmethoxysilane, trimethylethoxysilane, hexamethyldisilazane and hexaphenyldisiloxane; the hydrosilane end-capping agent is HMe ₂ SiOSiMe ₂ H、HMe ₂ SiNSiMe ₂ H( ^H MM ^H )、HMe ₂ One or more of SiOEt.

11. The process for preparing a transparent photocurable high-refractive index mercapto silicone oil as set forth in claim 3, wherein: the molar ratio of the mercaptosilane monomer 1, the unsaturated symmetric episulfide silane monomer SES-Si, the mercaptosilane monomer 2, the aromatic alkoxy silane monomer and the blocking agent is (1.05-1.2): 1: (1.5-5): (0.6-15): (0.01-0.5); the adding amount of the organic solvent is 1 to 3 times of the sum of the mass of the mercaptosilane monomer 1 and the mass of the unsaturated symmetric episulfide silane monomer SES-Si; the dosage of the photoinitiator is 0.1 to 1 percent of the sum of the mass of the mercaptosilane monomer and the mass of the unsaturated symmetric episulfide silane monomer SES-Si; the adding amount of the inert water absorbent is 0.5 to 1 time of the sum of the mass of the mercaptosilane monomer 1, the mass of the unsaturated symmetric episulfide silane monomer SES-Si, the mass of the mercaptosilane monomer 2 and the mass of the aromatic alkoxy silane monomer; the mol ratio of the episulfide stabilizer to the unsaturated symmetric episulfide silane monomer SES-Si is (1.05-1.1): 1; the dosage of the catalyst is 0.2 to 0.8 percent of the sum of the mass of the mercaptosilane monomer 1, the mass of the unsaturated symmetric episulfide silane monomer SES-Si, the mass of the mercaptosilane monomer 2 and the mass of the aromatic alkoxy silane monomer.

12. The process for preparing a transparent photocurable high-refractive index mercapto silicone oil as set forth in claim 3, wherein: the molar addition amount of the deionized water is 1.4-1.6 times of the molar addition amount of the mercaptosilane monomer 1, the mercaptosilane monomer 2 and the aromatic alkoxy silane monomer.

13. The process for preparing a transparent photocurable high-refractive index mercapto silicone oil as set forth in claim 3, wherein: after telomerization, the purification step comprises neutralization after temperature reduction, primary distillation, water washing and separation; preparing a neutralizing agent into a saturated solution of 50% ethanol-water, and taking the saturated solution as a water washing liquid in a water washing step; the primary distillation refers to reduced pressure distillation at 30-40 ℃ and-0.095 MPa to distill out alcohol in the system; and (2) after water washing and layering, taking an organic solvent layer for separation and purification, wherein the separation and purification comprises secondary water washing and layering, secondary distillation and column chromatography, the secondary water washing and layering takes pure deionized water as water washing liquid, and a demulsifier is added, and the secondary distillation refers to reduced pressure distillation at 70-90 ℃ and-0.095 MPa to remove the solvent in the system.

14. The method for preparing a transparent photocurable high refractive index mercapto silicone oil as set forth in claim 13, wherein: the neutralizer comprises one or more of sodium carbonate, calcium carbonate, magnesium carbonate, ammonium carbonate, sodium bicarbonate, ammonium bicarbonate and magnesium bicarbonate; the demulsifier is one or more of SP-169, BBE20601, AP-05, HA-22, HA-42, DE0712, AE8051, AE9901 and AP113, and the addition amount of the demulsifier is 0.1-0.5% of the sum of the mass of the mercaptosilane monomer 1, the mass of the unsaturated symmetric episulfide silane monomer SES-Si, the mass of the mercaptosilane monomer 2, the mass of the aromatic alkoxy silane monomer and the mass of the organic solvent.