A hydrophobic additive and method of using the same

Abstract

The invention discloses a kind of hydrophobic additive and its use method, belong to the field of hydrophobic additive preparation technology.The hydrophobic additive, is composed of the following components in parts by weight: 7-10 parts of active ingredient A, 1-3 parts of active ingredient B, 0.1-0.4 parts of solubilizers, 32-46 parts of solvents, wherein active ingredient A is prepared by ethyltriethoxysilane, triisopropanolamine, acrylic acid, methyl methacrylate and trifluoroethyl methacrylate, and active ingredient B is prepared by 2-perfluorohexylbromoethane, dimethylaminoethyl methacrylate, poly (ethylene glycol) methacrylate and 2-methyl-2-[(dodecylthiothiocarbonyl) sulphur] propionic acid.Hydrophobic additive is added to the slow pulling process, it is possible to effectively improve the silicon wafer yield, wherein the yield is up to 99.21%.

Description

Technical Field

[0001] The invention belongs to the technical field of preparation of hydrophobic additives, is applicable to a slow pulling process in the field of solar cell manufacturing, and specifically relates to a hydrophobic additive and a method for using the same. Background Art

[0002] The development background of solar cell technology stems from two key factors: First, global energy demand has risen sharply with economic growth, while traditional fossil fuels such as coal, oil and natural gas are not only limited in reserves, but their use has also exacerbated environmental problems such as greenhouse gas emissions and climate change. Second, environmental challenges highlight the urgency of finding sustainable solutions and promote the pursuit of clean energy. As an almost endless natural energy source, solar energy, the technology of converting it into electrical energy - solar cells, has gradually become an important way to alleviate the energy crisis and protect the ecological environment. Since the oil crisis in the 1970s, solar cell technology has experienced rapid development, and technological innovation has continuously promoted its efficiency and economy, allowing it to expand from professional fields to a wide range of civil and commercial applications, laying the foundation for the transformation of the global energy structure.

[0003] Slow pulling is an important process in the production of photovoltaic solar cells. It uses the surface tension of water to slowly pull the silicon wafer out of the water surface, partially peeling off the water from the surface of the silicon wafer, thereby obtaining a relatively dry silicon wafer and preventing the silicon wafer from sticking together, thus avoiding affecting the production yield of the silicon wafer. Due to the hydrophilicity of the oxide layer on the surface of the silicon wafer, there is still a problem of high water content on the surface of the silicon wafer during the slow pulling process, and the pre-drying effect is not very ideal, resulting in low EL yield and high proportion of basket prints. Summary of the invention

[0004] In view of the problem of unsatisfactory pre-drying effect in the existing slow pulling process, the present invention provides a hydrophobic additive and a method for using the same. By adding the hydrophobic additive to water, the surface tension of water is reduced, and the desorption of water on the surface of the silicon wafer is improved, thereby enhancing the pre-dehydration effect of the slow pulling process and significantly improving the problems of low EL yield and high basket print ratio.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] The invention provides a hydrophobic additive, which is composed of the following components in parts by weight: 7-10 parts of an effective component A, 1-3 parts of an effective component B, 0.1-0.4 parts of a solubilizer, and 32-46 parts of a solvent, wherein the effective component A is prepared from ethyltriethoxysilane, triisopropanolamine, acrylic acid, methyl methacrylate and trifluoroethyl methacrylate, and the effective component B is prepared from 2-perfluorohexylethyl bromide, dimethylaminoethyl methacrylate, poly(ethylene glycol) methacrylate and 2-methyl-2-[(dodecylthiothiocarbonyl)thio]propionic acid.

[0007] Preferably, the solvent is composed of one or more combinations of water, glycerol, ethanol, ethyl acetate and N,N-dimethylformamide.

[0008] Preferably, the method for preparing the active ingredient A comprises the following steps:

[0009] Q1: Add ethyltriethoxysilane, triisopropanolamine and p-toluenesulfonic acid to a three-necked flask, introduce nitrogen, react under heating and stirring, and then react under reduced pressure. After the reaction is completed, add ethyltriethoxysilane and p-toluenesulfonic acid to the three-necked flask, introduce nitrogen, react under heating and stirring, and then react under reduced pressure. After the reaction is completed, add triisopropanolamine and p-toluenesulfonic acid to the three-necked flask again, introduce nitrogen, react under heating and stirring, and then react under reduced pressure. After the reaction is completed, cool and obtain intermediate product 1;

[0010] Q2: Dissolve the intermediate product 1 with N,N-dimethylacetamide, add p-toluenesulfonic acid, stir and mix, and transfer to a four-necked flask. Mix acrylic acid, hydroquinone and N,N-dimethylacetamide and transfer to a constant pressure dropping funnel. Slowly add dropwise to the four-necked flask under heating and stirring conditions. After the reaction at normal pressure, perform a reduced pressure reaction. After the reaction is completed, perform rotary evaporation and cool down to obtain the intermediate product 2.

[0011] Q3: Add sodium dodecyl sulfonate, emulsifier, initiator and deionized water into beaker 1 and stir; add intermediate product 2, methyl methacrylate and trifluoroethyl methacrylate into beaker 1 and stir well to obtain pre-emulsion; add sodium dodecyl sulfonate, emulsifier and deionized water into beaker 2 and heat and stir until uniformly dispersed; then add 5% of the pre-emulsion, ammonium persulfate and deionized water, increase the temperature after addition, and then continue to add 95% of the pre-emulsion and react; after the reaction, adjust the pH to obtain active ingredient A.

[0012] In the above process, ethyltriethoxysilane and triisopropanolamine are reacted with p-toluenesulfonic acid as a catalyst to obtain an intermediate product 1, and then the intermediate product 1 reacts with acrylic acid to obtain an intermediate product 2 containing a terminal double bond, and then the intermediate product 2 can undergo an addition reaction with methyl methacrylate and trifluoroethyl methacrylate to obtain an effective component A, wherein the synthesis reaction formula of the effective component A is as follows:

[0013]

[0014] Preferably, in Q1, the molar ratio of ethyltriethoxysilane added for the first time, triisopropanolamine added for the first time, p-toluenesulfonic acid added for the first time, ethyltriethoxysilane added for the second time, p-toluenesulfonic acid added for the second time, triisopropanolamine added for the second time and p-toluenesulfonic acid added for the third time is (1-2):(3-6):(0.005-0.01):(6-12):(0.015-0.03):(12-24):(0.02-0.04), the heating and stirring temperatures are all 130-145°C, the reaction times are all 2-3h, and the reduced pressure reaction time is all 2-3h.

[0015] Preferably, in Q2, the molar ratio of the intermediate product 1 and acrylic acid is (1-1.5):(24-36), the heating and stirring temperature is 105-115°C, the reaction time at normal pressure is 4-6h, and the reduced pressure reaction time is 2-3h; in Q3, the molar ratio of the intermediate product 2, methyl methacrylate and trifluoroethyl methacrylate is (1-2):(24-48):(24-48), the stirring time is 30-45min, the heating and stirring temperature is 50-60°C, the stirring time is 45-60min, the heating temperature is 80-85°C, the reaction time is 2-3h, and the pH is adjusted to 7-7.2 with aqueous ammonia.

[0016] Preferably, the method for preparing the active ingredient B comprises the following steps:

[0017] S1: Add 2-perfluorohexylethyl bromide and dimethylaminoethyl methacrylate to a container containing acetonitrile, react in an oil bath under a nitrogen atmosphere, and then concentrate by rotary evaporation to obtain a reaction solution, add the reaction solution to diethyl ether, and allow to settle. After the precipitation is complete, dry the precipitate to obtain a fluorine-containing salt monomer;

[0018] S2: Add fluorine-containing salt monomer, poly (ethylene glycol) methacrylate, 2-methyl-2-[(dodecylthiocarbonyl)thio]propionic acid and azobisisobutyronitrile to a container containing chloroform, react in an oil bath under a nitrogen atmosphere, add to n-hexane, let stand to precipitate, remove the supernatant, wash the precipitate, dry it, redissolve it, purify it, and dry it to obtain active ingredient B.

[0019] In the above process, 2-perfluorohexylethyl bromide and dimethylaminoethyl methacrylate are subjected to quaternization reaction to obtain a fluorine-containing salt monomer, and then the fluorine-containing salt monomer, poly(ethylene glycol) methacrylate and 2-methyl-2-[(dodecylthiothiocarbonyl)thio]propionic acid are subjected to RAFT polymerization reaction to prepare an effective component B, wherein the synthesis reaction formula of the effective component B is as follows:

[0020]

[0021] Preferably, in S1, the molar ratio of 2-perfluorohexylethyl bromide to dimethylaminoethyl methacrylate is (1-2):(1.1-2.1), the oil bath reaction temperature is 60-65° C., and the reaction time is 48-52 h.

[0022] Preferably, in S2, the molar ratio of the fluorine-containing salt monomer, poly(ethylene glycol) methacrylate, 2-methyl-2-[(dodecylthiocarbonyl)thio]propionic acid and azobisisobutyronitrile is (1-2):(1-2):(1.2-2.4):(0.6-1.2), the oil bath reaction temperature is 60-70°C, the reaction time is 20-24h, and purification is carried out with deionized water.

[0023] A method for preparing a hydrophobic additive comprises the following steps:

[0024] Step (1): mixing active ingredient A and active ingredient B and stirring for 30 minutes to obtain a mixed active ingredient;

[0025] Step (2): slowly add the solvent to the mixed active ingredients, stir for 2 hours, then continue to add the solubilizer, stir and mix for 45 minutes to obtain a hydrophobic additive.

[0026] Preferably, a method for using a hydrophobic additive comprises adding the hydrophobic additive according to any one of claims 1 to 9 into a slow pulling tank, wherein the effective amount of the hydrophobic additive added to the slow pulling tank is 0.001% to 20% of the volume of water in the slow pulling tank, and the effective temperature is -10 to 100°C.

[0027] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0028] 1. The present invention first uses ethyltriethoxysilane, triisopropanolamine, acrylic acid, methyl methacrylate and trifluoroethyl methacrylate as raw materials to prepare effective ingredient A, then uses 2-perfluorohexylethyl bromide, dimethylaminoethyl methacrylate, poly(ethylene glycol) methacrylate and 2-methyl-2-[(dodecylthiothiocarbonyl)thio]propionic acid as raw materials to prepare effective ingredient B, uses effective ingredient A and effective ingredient B as components of a hydrophobic additive, and adds the hydrophobic additive to a slow pulling process for producing solar cells, which can effectively improve the yield of silicon wafers.

[0029] 2. The present invention uses ethyltriethoxysilane, triisopropanolamine, acrylic acid, methyl methacrylate and trifluoroethyl methacrylate as raw materials to prepare effective ingredient A, which is used as one of the effective ingredients of the hydrophobic additive, can effectively reduce the surface tension of water, improve the desorption of water on the surface of the silicon wafer, thereby improving the product yield. The fluoride ions contained in trifluoroethyl methacrylate have extremely low surface energy, so that the effective ingredient A tends to repel other substances when in contact with them, thereby showing excellent hydrophobicity.

[0030] 3. The present invention uses 2-perfluorohexylethyl bromide, dimethylaminoethyl methacrylate, poly(ethylene glycol) methacrylate and 2-methyl-2-[(dodecylthiocarbonyl)thio]propionic acid as raw materials to prepare active ingredient B, which contains fluorinated segments derived from 2-perfluorohexylethyl bromide. The presence of fluoride ions makes the active ingredient B have excellent hydrophobicity. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] Example 1

[0033] This embodiment discloses a method for preparing an active ingredient A, comprising the following steps:

[0034] Q1: 2.67 g of ethyltriethoxysilane, 7.97 g of triisopropanolamine and 0.015 g of p-toluenesulfonic acid were added to a three-necked flask, nitrogen was introduced, and the mixture was stirred at 140° C. for 3 h, followed by a reduced pressure reaction for 2 h. After the reaction was completed, 16.02 g of ethyltriethoxysilane and 0.038 g of p-toluenesulfonic acid were added to the three-necked flask, nitrogen was introduced, and the mixture was stirred at 140° C. for 3 h, followed by a reduced pressure reaction for 2 h. After the reaction was completed, 31.88 g of triisopropanolamine and 0.047 g of p-toluenesulfonic acid were added to the three-necked flask, nitrogen was introduced, and the mixture was stirred at 140° C. for 3 h, followed by a reduced pressure reaction for 2 h. After the reaction was completed, the mixture was cooled to obtain an intermediate product 1.

[0035] Q2: 3.86g of intermediate product 1 was dissolved in 10mL N,N-dimethylacetamide, and 0.012g of p-toluenesulfonic acid was added at the same time. After stirring and mixing, the mixture was transferred to a four-necked flask. 5g of acrylic acid, 0.5g of hydroquinone and 10mL of N,N-dimethylacetamide were mixed and transferred to a constant pressure dropping funnel. Under heating and stirring at 115°C, the mixture was slowly added dropwise to the four-necked flask. After reacting at normal pressure for 6h, the mixture was reacted under reduced pressure for 2h. After the reaction was completed, the mixture was rotary evaporated and cooled to obtain intermediate product 2.

[0036] Q3: 1.25 g sodium dodecyl sulfonate, 0.6 g OP-10, 0.04 g ammonium persulfate and 10 mL deionized water were added to beaker 1 and stirred. 2.18 g intermediate product 2, 6 g methyl methacrylate and 6.48 g trifluoroethyl methacrylate were added to beaker 1 and stirred for 45 min to obtain a pre-emulsion. 2.5 g sodium dodecyl sulfonate, 1.2 g OP-10 and 20 mL deionized water were added to beaker 2 and heated and stirred at 55 ° C for 60 min until uniformly dispersed. Subsequently, 5% of the pre-emulsion, 0.06 g ammonium persulfate and 12 mL deionized water were added. After adding, the temperature was raised to 80 ° C, and then 95% of the pre-emulsion was added. After reacting for 2 h, the pH was adjusted to 7 with ammonia water to obtain active ingredient A.

[0037] This embodiment discloses a method for preparing an active ingredient B, comprising the following steps:

[0038] S1: 1.95 g of 2-perfluorohexylethyl bromide and 0.76 g of dimethylaminoethyl methacrylate were added to a container containing acetonitrile, and the mixture was reacted in an oil bath at 65° C. for 48 h under a nitrogen atmosphere. The reaction solution was concentrated by rotary evaporation, and the reaction solution was added to diethyl ether, and allowed to stand for precipitation. After the precipitation was complete, the precipitate was dried to obtain a fluorine-containing salt monomer;

[0039] S2: Add 1.5 g of fluorine-containing salt monomer, 1.16 g of poly(ethylene glycol) methacrylate, 0.96 g of 2-methyl-2-[(dodecylthiocarbonyl)thio]propionic acid and 0.21 g of azobisisobutyronitrile into a container containing 10 mL of chloroform, react in an oil bath at 65°C under a nitrogen atmosphere for 24 hours, add to n-hexane, let stand to precipitate, remove the supernatant, wash the precipitate, dry it, redissolve it, purify it with deionized water, and dry it to obtain active ingredient B.

[0040] This embodiment discloses a hydrophobic additive, which is composed of the following components in parts by weight: 8.5 parts of active ingredient A, 2 parts of active ingredient B, 0.25 parts of Tween 80, 22 parts of water, and 17 parts of ethanol.

[0041] This embodiment discloses a method for preparing a hydrophobic additive, comprising the following steps:

[0042] Step (1): mixing active ingredient A and active ingredient B and stirring for 30 minutes to obtain a mixed active ingredient;

[0043] Step (2): slowly add water and ethanol to the mixed active ingredients, stir for 2 hours, then continue to add Tween 80, stir and mix for 45 minutes to obtain a hydrophobic additive.

[0044] This embodiment discloses a method for using a hydrophobic additive, wherein the prepared hydrophobic additive is added to a slow pull tank, wherein the effective amount of the hydrophobic additive added to the slow pull tank is 8% of the water volume in the slow pull tank, and the effective temperature is 50°C.

[0045] Example 2

[0046] This embodiment discloses a method for preparing an active ingredient A, comprising the following steps:

[0047] Q1: 1.78 g of ethyltriethoxysilane, 5.31 g of triisopropanolamine and 0.01 g of p-toluenesulfonic acid were added to a three-necked flask, nitrogen was introduced, and the mixture was stirred at 140° C. for 3 h, followed by a reduced pressure reaction for 2 h. After the reaction was completed, 10.68 g of ethyltriethoxysilane and 0.025 g of p-toluenesulfonic acid were added to the three-necked flask, nitrogen was introduced, and the mixture was stirred at 140° C. for 3 h, followed by a reduced pressure reaction for 2 h. After the reaction was completed, 21.24 g of triisopropanolamine and 0.03 g of p-toluenesulfonic acid were added to the three-necked flask, nitrogen was introduced, and the mixture was stirred at 140° C. for 3 h, followed by a reduced pressure reaction for 2 h. After the reaction was completed, the mixture was cooled to obtain an intermediate product 1.

[0048] Q2: 3.08 g of intermediate product 1 was dissolved in 10 mL of N, N-dimethylacetamide, and 0.012 g of p-toluenesulfonic acid was added. After stirring, the mixture was transferred to a four-necked flask. 4 g of acrylic acid, 0.5 g of hydroquinone and 10 mL of N, N-dimethylacetamide were mixed and transferred to a constant pressure dropping funnel. Under heating and stirring at 115°C, the mixture was slowly added dropwise to the four-necked flask. After reacting at normal pressure for 6 h, the mixture was reacted under reduced pressure for 2 h. After the reaction was completed, the mixture was rotary evaporated and cooled to obtain intermediate product 2.

[0049] Q3: 1.25 g sodium dodecyl sulfate, 0.6 g OP-10, 0.04 g ammonium persulfate and 10 mL deionized water were added to beaker 1 and stirred. 1.45 g intermediate product 2, 4 g methyl methacrylate and 4.32 g trifluoroethyl methacrylate were added to beaker 1 and stirred for 45 min to obtain a pre-emulsion. 2.5 g sodium dodecyl sulfate, 1.2 g OP-10 and 20 mL deionized water were added to beaker 2 and heated and stirred at 55 ° C for 60 min until uniformly dispersed. Subsequently, 5% of the pre-emulsion, 0.06 g ammonium persulfate and 12 mL deionized water were added. After adding, the temperature was raised to 80 ° C, and then 95% of the pre-emulsion was added. After reacting for 2 h, the pH was adjusted to 7 with ammonia water to obtain active ingredient A.

[0050] This embodiment discloses a method for preparing an active ingredient B, comprising the following steps:

[0051] S1: 1.3 g of 2-perfluorohexylethyl bromide and 0.52 g of dimethylaminoethyl methacrylate were added to a container containing acetonitrile, and the mixture was reacted in an oil bath at 65° C. for 48 h under a nitrogen atmosphere. The reaction solution was concentrated by rotary evaporation, and the reaction solution was added to diethyl ether, and allowed to stand for precipitation. After the precipitation was complete, the precipitate was dried to obtain a fluorine-containing salt monomer;

[0052] S2: Add 1 g of fluorine-containing salt monomer, 0.77 g of poly(ethylene glycol) methacrylate, 0.64 g of 2-methyl-2-[(dodecylthiocarbonyl)thio]propionic acid and 0.14 g of azobisisobutyronitrile into a container containing 10 mL of chloroform, react in an oil bath at 65°C under a nitrogen atmosphere for 24 hours, add to n-hexane, let stand to precipitate, remove the supernatant, wash the precipitate, dry it, redissolve it, purify it with deionized water, and dry it to obtain active ingredient B.

[0053] This embodiment discloses a hydrophobic additive, which is composed of the following components in parts by weight: 7 parts of active ingredient A, 1 part of active ingredient B, 0.1 parts of Tween 80, 20 parts of water, and 12 parts of ethanol.

[0054] This embodiment discloses a method for preparing a hydrophobic additive, comprising the following steps:

[0055] Step (1): mixing active ingredient A and active ingredient B and stirring for 30 minutes to obtain a mixed active ingredient;

[0056] Step (2): slowly add water and ethanol to the mixed active ingredients, stir for 2 hours, then continue to add Tween 80, stir and mix for 45 minutes to obtain a hydrophobic additive.

[0057] This embodiment discloses a method for using a hydrophobic additive, wherein the prepared hydrophobic additive is added to a slow pull tank, wherein the effective amount of the hydrophobic additive added to the slow pull tank is 8% of the water volume in the slow pull tank, and the effective temperature is 50°C.

[0058] Example 3

[0059] This embodiment discloses a method for preparing an active ingredient A, comprising the following steps:

[0060] Q1: 3.56 g of ethyltriethoxysilane, 10.62 g of triisopropanolamine and 0.02 g of p-toluenesulfonic acid were added to a three-necked flask, nitrogen was introduced, and the mixture was stirred at 140° C. for 3 h, followed by a reduced pressure reaction for 2 h. After the reaction was completed, 21.36 g of ethyltriethoxysilane and 0.05 g of p-toluenesulfonic acid were added to the three-necked flask, nitrogen was introduced, and the mixture was stirred at 140° C. for 3 h, followed by a reduced pressure reaction for 2 h. After the reaction was completed, 42.5 g of triisopropanolamine and 0.064 g of p-toluenesulfonic acid were added to the three-necked flask, nitrogen was introduced, and the mixture was stirred at 140° C. for 3 h, followed by a reduced pressure reaction for 2 h. After the reaction was completed, the mixture was cooled to obtain an intermediate product 1.

[0061] Q2: Dissolve 4.63g of intermediate product 1 in 10mL N,N-dimethylacetamide, add 0.012g of p-toluenesulfonic acid, stir and mix, and transfer to a four-necked flask. Mix 6g of acrylic acid, 0.5g of hydroquinone and 10mL of N,N-dimethylacetamide and transfer to a constant pressure dropping funnel. Slowly add dropwise to the four-necked flask under heating and stirring at 115°C. React at normal pressure for 6h, then under reduced pressure for 2h. After the reaction is completed, rotary evaporate and cool to obtain intermediate product 2.

[0062] Q3: 1.25 g sodium dodecyl sulfonate, 0.6 g OP-10, 0.04 g ammonium persulfate and 10 mL deionized water were added to beaker 1 and stirred. 2.9 g intermediate product 2, 8 g methyl methacrylate and 8.64 g trifluoroethyl methacrylate were added to beaker 1 and stirred for 45 min to obtain a pre-emulsion. 2.5 g sodium dodecyl sulfonate, 1.2 g OP-10 and 20 mL deionized water were added to beaker 2 and heated and stirred at 55 ° C for 60 min until uniformly dispersed. Subsequently, 5% of the pre-emulsion, 0.06 g ammonium persulfate and 12 mL deionized water were added. After adding, the temperature was raised to 80 ° C, and then 95% of the pre-emulsion was added. After reacting for 2 h, the pH was adjusted to 7 with ammonia water to obtain active ingredient A.

[0063] This embodiment discloses a method for preparing an active ingredient B, comprising the following steps:

[0064] S1: 2.59 g of 2-perfluorohexylethyl bromide and 1 g of dimethylaminoethyl methacrylate were added to a container containing acetonitrile, and the mixture was reacted in an oil bath at 65°C for 48 h under a nitrogen atmosphere. The reaction solution was concentrated by rotary evaporation, and the reaction solution was added to diethyl ether, and allowed to stand for precipitation. After the precipitation was complete, the precipitate was dried to obtain a fluorine-containing salt monomer;

[0065] S2: Add 2 g of fluorine-containing salt monomer, 1.54 g of poly(ethylene glycol) methacrylate, 1.28 g of 2-methyl-2-[(dodecylthiocarbonyl)thio]propionic acid and 0.28 g of azobisisobutyronitrile into a container containing 10 mL of chloroform, react in an oil bath at 65°C under a nitrogen atmosphere for 24 hours, add to n-hexane, let stand to precipitate, remove the supernatant, wash the precipitate, dry it, redissolve it, purify it with deionized water, and dry it to obtain active ingredient B.

[0066] This embodiment discloses a hydrophobic additive, which is composed of the following components in parts by weight: 10 parts of active ingredient A, 3 parts of active ingredient B, 0.4 parts of Tween 80, 25 parts of water, and 21 parts of ethanol.

[0067] This embodiment discloses a method for preparing a hydrophobic additive, comprising the following steps:

[0068] Step (1): mixing active ingredient A and active ingredient B and stirring for 30 minutes to obtain a mixed active ingredient;

[0069] Step (2): slowly add water and ethanol to the mixed active ingredients, stir for 2 hours, then continue to add Tween 80, stir and mix for 45 minutes to obtain a hydrophobic additive.

[0070] This embodiment discloses a method for using a hydrophobic additive, wherein the prepared hydrophobic additive is added to a slow pull tank, wherein the effective amount of the hydrophobic additive added to the slow pull tank is 8% of the water volume in the slow pull tank, and the effective temperature is 50°C.

[0071] Example 4

[0072] This embodiment discloses a method for preparing an active ingredient A, comprising the following steps:

[0073] Q1: 3.12 g of ethyltriethoxysilane, 6.64 g of triisopropanolamine and 0.012 g of p-toluenesulfonic acid were added to a three-necked flask, nitrogen was introduced, and the mixture was stirred at 140° C. for 3 h, followed by a reduced pressure reaction for 2 h. After the reaction was completed, 18.7 g of ethyltriethoxysilane and 0.044 g of p-toluenesulfonic acid were added to the three-necked flask, nitrogen was introduced, and the mixture was stirred at 140° C. for 3 h, followed by a reduced pressure reaction for 2 h. After the reaction was completed, 26.56 g of triisopropanolamine and 0.039 g of p-toluenesulfonic acid were added to the three-necked flask, nitrogen was introduced, and the mixture was stirred at 140° C. for 3 h, followed by a reduced pressure reaction for 2 h. After the reaction was completed, the mixture was cooled to obtain an intermediate product 1.

[0074] Q2: 3.47 g of intermediate product 1 was dissolved in 10 mL of N, N-dimethylacetamide, and 0.012 g of p-toluenesulfonic acid was added at the same time. After stirring and mixing, the mixture was transferred to a four-necked flask. 4.6 g of acrylic acid, 0.5 g of hydroquinone and 10 mL of N, N-dimethylacetamide were mixed and transferred to a constant pressure dropping funnel. Under heating and stirring at 115°C, the mixture was slowly added dropwise to the four-necked flask. After reacting at normal pressure for 6 h, the reaction was then carried out under reduced pressure for 2 h. After the reaction was completed, the mixture was rotary evaporated and cooled to obtain intermediate product 2.

[0075] Q3: 1.25 g sodium dodecyl sulfonate, 0.6 g OP-10, 0.04 g ammonium persulfate and 10 mL deionized water were added to beaker 1 and stirred. 1.82 g intermediate product 2, 5 g methyl methacrylate and 7.56 g trifluoroethyl methacrylate were added to beaker 1 and stirred for 45 min to obtain a pre-emulsion. 2.5 g sodium dodecyl sulfonate, 1.2 g OP-10 and 20 mL deionized water were added to beaker 2 and heated and stirred at 55°C for 60 min until uniformly dispersed. Subsequently, 5% of the pre-emulsion, 0.06 g ammonium persulfate and 12 mL deionized water were added. The temperature was raised to 80°C after addition, and then 95% of the pre-emulsion was added. After reacting for 2 h, the pH was adjusted to 7 with ammonia water to obtain active ingredient A.

[0076] This embodiment discloses a method for preparing an active ingredient B, comprising the following steps:

[0077] S1: 1.63 g of 2-perfluorohexylethyl bromide and 0.88 g of dimethylaminoethyl methacrylate were added to a container containing acetonitrile, and the mixture was reacted in an oil bath at 65° C. for 48 h under a nitrogen atmosphere. The reaction solution was concentrated by rotary evaporation, and the reaction solution was added to diethyl ether, and allowed to stand for precipitation. After the precipitation was complete, the precipitate was dried to obtain a fluorine-containing salt monomer;

[0078] S2: Add 1.2 g of fluorine-containing salt monomer, 1.35 g of poly(ethylene glycol) methacrylate, 1.12 g of 2-methyl-2-[(dodecylthiocarbonyl)thio]propionic acid and 0.18 g of azobisisobutyronitrile into a container containing 10 mL of chloroform, react in an oil bath at 65°C under a nitrogen atmosphere for 24 hours, add to n-hexane, let stand to precipitate, remove the supernatant, wash the precipitate, dry it, redissolve it, purify it with deionized water, and dry it to obtain active ingredient B.

[0079] This embodiment discloses a hydrophobic additive, which is composed of the following components in parts by weight: 8 parts of active ingredient A, 1.5 parts of active ingredient B, 0.2 parts of Tween 80, 24 parts of water, and 18 parts of ethanol.

[0080] This embodiment discloses a method for preparing a hydrophobic additive, comprising the following steps:

[0081] Step (1): mixing active ingredient A and active ingredient B and stirring for 30 minutes to obtain a mixed active ingredient;

[0082] Step (2): slowly add water and ethanol to the mixed active ingredients, stir for 2 hours, then continue to add Tween 80, stir and mix for 45 minutes to obtain a hydrophobic additive.

[0083] This embodiment discloses a method for using a hydrophobic additive, wherein the prepared hydrophobic additive is added to a slow pull tank, wherein the effective amount of the hydrophobic additive added to the slow pull tank is 8% of the water volume in the slow pull tank, and the effective temperature is 50°C.

[0084] Comparative Example 1

[0085] Comparative Example 1 Compared with Example 1, in the preparation process of the active ingredient A in Comparative Example 1, ethyltriethoxysilane was not added, and other conditions remained unchanged.

[0086] Comparative Example 2

[0087] Comparative Example 2 Compared with Example 1, in the preparation process of the active ingredient A in Comparative Example 2, trifluoroethyl methacrylate was not added, and other conditions remained unchanged.

[0088] Comparative Example 3

[0089] Comparative Example 3 Compared with Example 1, in the preparation process of the active ingredient B in Comparative Example 3, 2-perfluorohexylethyl bromide was not added, and other conditions remained unchanged.

[0090] Comparative Example 4

[0091] Comparative Example 4 Compared with Example 1, in the preparation process of the active ingredient B in Comparative Example 4, no poly(ethylene glycol) methacrylate was added, and other conditions remained unchanged.

[0092] Comparative Example 5

[0093] Comparative Example 5 Compared with Example 1, in the preparation process of the hydrophobic additive in Comparative Example 5, no active ingredient A is added, and other conditions remain unchanged.

[0094] Comparative Example 6

[0095] Comparative Example 6 Compared with Example 1, in the preparation process of the hydrophobic additive in Comparative Example 6, no active ingredient B is added, and other conditions remain unchanged.

[0096] According to the methods of Examples 1-4 and Comparative Examples 1-6, during the slow pulling process, the number of silicon wafers prepared was 100, the operation was repeated 3 times, and the product yield was averaged. The obtained silicon wafers were tested according to DB61 / T 512-2011, and a blank group was set, in which no hydrophobic additive was added. The test results are shown in Table 1:

[0097] Table 1

[0098] project Product yield / % Example 1 99.21 Example 2 99.16 Example 3 99.13 Example 4 99.17 Comparative Example 1 97.94 Comparative Example 2 97.85 Comparative Example 3 98.18 Comparative Example 4 98.34 Comparative Example 5 97.46 Comparative Example 6 98.05 Blank Group 97.15

[0099] It can be seen from the test results in Table 1 that the hydrophobic additives prepared in Examples 1-4 of the present invention can effectively improve the product yield. By comparing Comparative Example 1 with Examples 1-4, it can be seen that the addition of ethyltriethoxysilane can improve the product yield; by comparing Comparative Example 2 with Examples 1-4, it can be seen that the addition of trifluoroethyl methacrylate can improve the product yield; by comparing Comparative Example 3 with Examples 1-4, it can be seen that the addition of 2-perfluorohexyl bromoethane can improve the product yield; by comparing Comparative Example 4 with Examples 1-4, it can be seen that the addition of poly (ethylene glycol) methacrylate can improve the product yield; by comparing Comparative Example 5 with Examples 1-4, it can be seen that the addition of active ingredient A can improve the product yield; by comparing Comparative Example 6 with Examples 1-4, it can be seen that the addition of active ingredient B can improve the product yield.

[0100] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0101] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A hydrophobic additive, characterized in that: The invention is composed of the following components in parts by weight: 7-10 parts of active ingredient A, 1-3 parts of active ingredient B, 0.1-0.4 parts of solubilizer, and 32-46 parts of solvent; The preparation method of active ingredient A comprises the following steps: Q1: Add ethyltriethoxysilane, triisopropanolamine and p-toluenesulfonic acid to a three-necked flask, introduce nitrogen, react under heating and stirring, and then react under reduced pressure. After the reaction is completed, add ethyltriethoxysilane and p-toluenesulfonic acid to the three-necked flask, introduce nitrogen, react under heating and stirring, and then react under reduced pressure. After the reaction is completed, add triisopropanolamine and p-toluenesulfonic acid to the three-necked flask again, introduce nitrogen, react under heating and stirring, and then react under reduced pressure. After the reaction is completed, cool and obtain intermediate product 1; Q2: Dissolve the intermediate product 1 with N,N-dimethylacetamide, add p-toluenesulfonic acid, stir and mix, and transfer to a four-necked flask. Mix acrylic acid, hydroquinone and N,N-dimethylacetamide and transfer to a constant pressure dropping funnel. Slowly add dropwise to the four-necked flask under heating and stirring conditions. After the reaction at normal pressure, perform a reduced pressure reaction. After the reaction is completed, perform rotary evaporation and cool down to obtain the intermediate product 2. Q3: Add sodium dodecyl sulfonate, OP-10, initiator and deionized water to beaker 1, stir, add intermediate product 2, methyl methacrylate and trifluoroethyl methacrylate to beaker 1, stir well to obtain pre-emulsion, add sodium dodecyl sulfonate, OP-10 and deionized water to beaker 2, heat and stir until uniformly dispersed, then add 5% of pre-emulsion, ammonium persulfate and deionized water, heat after adding, then continue to add 95% of pre-emulsion, react, adjust pH after reaction, and obtain active ingredient A; The preparation method of active ingredient B comprises the following steps: S1: Add 2-perfluorohexylethyl bromide and dimethylaminoethyl methacrylate to a container containing acetonitrile, react in an oil bath under a nitrogen atmosphere, and then concentrate by rotary evaporation to obtain a reaction solution, add the reaction solution to diethyl ether, and allow to settle. After the precipitation is complete, dry the precipitate to obtain a fluorine-containing salt monomer; S2: Add fluorine-containing salt monomer, poly (ethylene glycol) methacrylate, 2-methyl-2-[(dodecylthiocarbonyl)thio]propionic acid and azobisisobutyronitrile to a container containing chloroform, react in an oil bath under a nitrogen atmosphere, add to n-hexane, let stand to precipitate, remove the supernatant, wash the precipitate, dry it, redissolve it, purify it, and dry it to obtain the effective ingredient.

2. The hydrophobic additive according to claim 1, characterized in that The solvent is composed of one or more combinations of water, glycerol, ethanol, ethyl acetate and N,N-dimethylformamide.

3. The hydrophobic additive according to claim 1, characterized in that In Q1, the molar ratios of the ethyltriethoxysilane added for the first time, the triisopropanolamine added for the first time, the p-toluenesulfonic acid added for the first time, the ethyltriethoxysilane added for the second time, the p-toluenesulfonic acid added for the second time, the triisopropanolamine added for the second time and the p-toluenesulfonic acid added for the third time are (1-2):(3-6):(0.005-0.01):(6-12):(0.015-0.03):(12-24):(0.02-0.04), the heating and stirring temperatures are all 130-145°C, the reaction times are all 2-3h, and the reduced pressure reaction times are all 2-3h.

4. The hydrophobic additive according to claim 1, characterized in that In the Q2, the molar ratio of the intermediate product 1 and acrylic acid is (1-1.5): (6-9), the heating and stirring temperature is 105-115°C, the reaction time at normal pressure is 4-6h, and the reduced pressure reaction time is 2-3h; in the Q3, the molar ratio of the intermediate product 2, methyl methacrylate and trifluoroethyl methacrylate is (1-2): (24-48): (24-48), the stirring time is 30-45min, the heating and stirring temperature is 50-60°C, the stirring time is 45-60min, the heating temperature is 80-85°C, the reaction time is 2-3h, and the pH is adjusted to 7-7.2 with aqueous ammonia.

5. The hydrophobic additive according to claim 1, characterized in that In the S1, the molar ratio of 2-perfluorohexylethyl bromide to dimethylaminoethyl methacrylate is (1-2): (1.1-2.1), the oil bath reaction temperature is 60-65° C., and the reaction time is 48-52 h.

6. The hydrophobic additive according to claim 1, characterized in that In S2, the molar ratio of the fluorine-containing salt monomer, poly(ethylene glycol) methacrylate, 2-methyl-2-[(dodecylthiocarbonyl)thio]propionic acid and azobisisobutyronitrile is (1-2):(1-2):(1.2-2.4):(0.6-1.2), the oil bath reaction temperature is 60-70°C, the reaction time is 20-24h, and purification is carried out with deionized water.

7. A method for preparing a hydrophobic additive according to any one of claims 1 to 6, characterized in that: The following steps are involved: Step (1): mixing active ingredient A and active ingredient B and stirring for 30 minutes to obtain a mixed active ingredient; Step (2): slowly add the solvent to the mixed active ingredients, stir for 2 hours, then continue to add the solubilizer, stir and mix for 45 minutes to obtain a hydrophobic additive.

8. A method for using a hydrophobic additive, characterized in that: The hydrophobic additive according to any one of claims 1 to 6 is added to the slow pulling tank, wherein the effective amount of the hydrophobic additive added to the slow pulling tank is 0.001%-20% of the water volume in the slow pulling tank, and the effective temperature is -10~100°C.

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