Silicon powder dispersing agent based on natural phenolic compound modification and preparation method of silicon powder dispersing agent

Abstract

The invention relates to the technical field of dispersing agents, in particular to a silicon powder dispersing agent based on natural phenolic compound modification and a preparation method of the silicon powder dispersing agent. According to the dispersing agent, the problems that a large amount of chippings and silicon powder are generated in the cutting process by diamond wire cutting liquid, dispersion is insufficient, the chippings and the silicon powder are prone to being attached to the surface of diamond wires or crystalline silicon, then the chippings and the silicon powder are bonded together, and the cutting precision is reduced are solved, and the prepared silicon powder dispersing agent and the composite dispersing composition are good in dispersing effect and high in dispersing speed; the stability is good.

Description

Technical Field

[0001] The present application relates to the technical field of dispersants, and in particular to a silicon powder dispersant modified based on natural phenolic compounds and a preparation method thereof. Background Art

[0002] With the development of photovoltaic solar cells, the rapid iteration of crystalline silicon materials, which are their main raw materials, has been promoted, thus putting forward higher requirements on the quality of silicon wafer cutting and processing. That is, under the current development situation of increasing diameter of crystalline silicon wafers and decreasing thickness and line width, the cutting process is required to ensure that the geometric dimensions of the silicon wafers and the mechanical damage on their surfaces are small and the lattice integrity is high. In addition, the cutting quality of silicon wafers will affect the processing efficiency of subsequent grinding, polishing and etching processes and even affect the final quality of semiconductor devices.

[0003] Currently, the primary technology for cutting silicon rods or ingots is diamond wire cutting (DWS). Diamond wire cutting fluid is a crucial component of this technology. The fluid penetrates between the wire mesh and the silicon wafer, and between the wire mesh and the debris, minimizing cutting damage, stress, and microcracks, while also reducing cutting resistance. Currently, the dispersant in the DWS generates a large amount of debris and silicon powder during the cutting process. This insufficient dispersion allows the debris and silicon powder to adhere to the diamond wire or crystalline silicon surface, causing them to aggregate and cling, reducing cutting accuracy, causing wire wear, and significantly increasing material loss, ultimately increasing wafer processing costs.

[0004] Chinese patent CN 117801258A discloses a green and environmentally friendly bio-based silica fume dispersant. This highly branched block polyether dispersant is synthesized by reacting natural polyhydroxy initiators such as sorbitol and mannitol with ethylene oxide and propylene oxide. The dispersant exhibits a moderate dispersing effect on silica fume. However, like the Pluronic RPE-type reverse-block polyether surfactant, this polyether structure lacks a separate hydrocarbon (alkane, alkene, alkyne, or aromatic) lipophilic group. Instead, it utilizes polyoxypropylene segments within the molecular structure as lipophilic groups. The molecular weight of the polyoxypropylene segments generally must be above 900 to achieve good hydrophobicity, which limits the adjustability of the molecular structure. Summary of the Invention

[0005] In order to effectively improve the problem of aggregation of debris and silicon powder in the existing diamond wire cutting process and reduced cutting accuracy, the present application provides a silicon powder dispersant modified by natural phenolic compounds and a preparation method thereof.

[0006] In a first aspect, the present application provides a silicon powder dispersant modified based on a natural phenolic compound; the dispersant comprises a cardol-modified polyether, the structural formula of which is as shown in Formula I: In Formula I, R 1 C15 H 25 -、C 15 H 27 -、C 15 H 29 -、C 15 H 31 - at least one straight-chain hydrocarbon structure; R 2 is H- or CH3-; (A 1 O)m and (A 2 O)n is a homopolyoxyalkylene segment, A 1 Including -CH2CH2-, -CH2CH(CH3)- or -CH2CH(CH2CH3)-, -CH2CH2O- in the whole (A 1 O) m polyoxyalkylene segment accounts for 50%-100%, preferably 60%-100%, preferably 80%-100%, m is an integer of 2-50; preferably, 4-20; A 2 Including -CH2CH2-, -CH2CH(CH3)- or -CH2CH(CH2CH3)-, -CH2CH2O- in the whole (A 2 O) n polyoxyalkylene chain segments account for 0-50%; preferably, 0-40%, preferably, 0%-30%; n is an integer of 2-50; preferably, 4-20.

[0007] The applicant has found that the dispersant with the above-mentioned structural components has good dispersibility. This may be due to the presence of long-chain polyoxyalkylene segments and pentadecyl segments at positions 1, 3, and 5 of the cardol-modified polyether. The long-chain distribution at the intervals can produce sufficient steric hindrance, which has a significant dispersing effect on silicon powder and prevents silicon powder from agglomerating or flocculating. The presence of the dipolyether segment improves the hydrophilicity, thereby improving the compatibility of the dispersant with water, which is beneficial to improving the wetting efficiency of silicon powder during cutting. On the other hand, the molecules of this structure are more tightly arranged, and the film formed on the liquid surface is not easily destroyed by external forces, thereby reducing the generation of bubbles. The dipolyether segment structure also improves the lubricity and permeability of the dispersant. The cutting fluid penetrates between the wire mesh and the silicon wafer, and between the wire mesh and the debris, forming a lubricating film, reducing cutting damage, stress, and microcracks. The better permeability can reduce friction and reduce cutting resistance.

[0008] Furthermore, the polyether segment's side chains also include methyl and ethyl groups, which provide excellent coverage and encapsulation for dispersed particles like silicon powder. By adjusting the content and position of the side chain groups within the same polyoxyalkylene segment, the dispersant achieves both excellent silicon powder encapsulation and lubrication, as well as permeability and low foaming properties, thereby improving cutting precision. Optimizing the position and content of the side groups further enhances the dispersant's aforementioned combined effects.

[0009] The preparation method of a silicon powder dispersant modified with a natural phenolic compound comprises the following steps: (1) obtaining a pentadecylphenol extract by multi-stage molecular distillation of cashew nut shell oil; (2) taking a pentadecylphenol extract, adding a catalyst I and a halopropylene oxide to cause an etherification reaction, then adding a ring-closing agent, continuing the reaction, and purifying to obtain pentadecylphenol glycidyl ether; (3) taking the above-mentioned pentadecylphenol glycidyl ether, adding protonic acid, deionized water and solvent to react; obtaining a hydrolysis product of pentadecylphenol glycidyl ether; (4) The hydrolyzed product of the pentadecylphenol glycerol ether and the catalyst II are stirred evenly, dehydrated, replaced with nitrogen, and 1,2-epoxyalkylene is added to react, and then post-treated to obtain a silicon powder dispersant modified with a natural phenolic compound.

[0010] Preferably, the method comprises the following steps: (1) Decarboxylated cashew nut shell liquid is used as a raw material, and fractions are separated by multi-stage molecular distillation at 160-200° C. to obtain a pentadecylphenol extract; (2) taking a pentadecylphenol extract, heating it to 60-100° C., adding catalyst I and halogenated epoxypropane to cause a ring-opening etherification reaction, then adding a ring-closing agent, reacting at 65-80° C. for 1-3 hours, and purifying to obtain pentadecylphenol glycidyl ether; (3) taking the pentadecylphenol glycidyl ether obtained above, adding protonic acid, deionized water and solvent 1, and reflux reacting at 50-100° C. for 2-6 hours, taking a sample to measure the epoxy value, when the epoxy value is ≤0.003, the hydrolysis is completed, vacuuming and removing solvent 1, adding solvent 2 and deionized water, and then adding a neutralizer to adjust the pH value to neutral, continuing to stir for 20-30 minutes, standing and separating the lower layer, heating the upper oil liquid to 80-150° C., vacuuming and removing the solvent, etc., to obtain the hydrolysis product of pentadecylphenol glyceryl ether.

[0011] (4) Adding the hydrolyzed product of pentadecylphenol glycerol ether and catalyst II to a high-pressure alkoxylation reactor and stirring evenly, heating to 70-135° C., vacuum dehydration for 30-120 minutes, sampling and testing to make the water content less than 0.1%, nitrogen replacement, adding 1,2-alkylene oxide to carry out alkoxylation reaction, adding phosphoric acid or potassium dihydrogen phosphate aqueous solution to neutralize catalyst II after the reaction, and then using silicate to adsorb the generated phosphate crystals, and finally adding an appropriate amount of diatomaceous earth and circulating filtration together until the potassium and sodium ions are less than 10 ppm, thereby obtaining a silicon powder dispersant modified by a natural phenolic compound.

[0012] By adopting the above technical solution, based on cashew nut shell crude oil, a pentadecylphenol extract fraction containing cardol and 2-methyl cardol is separated through multi-stage vacuum molecular distillation. Then, through halogenation and ring closure reaction, it is purified to obtain pentadecylphenol glycidyl ether. Subsequently, by adding protonic acid to open the ring, after nitrogen displacement, 1,2-epoxy alkane undergoes alkoxylation reaction, and then adsorption and filtration separation is obtained to obtain a silicon powder dispersant modified by natural phenolic compounds. This process greatly increases the proportion of cardol and 2-methyl cardol in crude oil through molecular distillation. Through a simple process, a molecular structure product with a meta-double hydrophilic bond and a single oleophilic bond is prepared. It can prepare a silicon powder dispersant containing a high content of cardol-modified polyether. The obtained dispersant has good dispersion, low foaming, lubrication, and penetration properties.

[0013] In a specific embodiment, the mixture of cardol and 2-methyl cardol in the extract of (1) accounts for 50-90% of the extract content.

[0014] Crude oil with a higher cardol content increases the content of cardol-modified polyether in the product, thereby improving the performance of the prepared dispersant.

[0015] The halogenated epoxypropane in (2) is selected from at least one of 3-chloro-1,2-epoxypropane, 3-bromo-1,2-epoxypropane and 3-iodo-1,2-epoxypropane, preferably 3-chloro-1,2-epoxypropane; the catalyst I is at least one of tetraalkylammonium halide and trialkylbenzylammonium halide; the tetraalkylammonium halide is selected from tetramethylammonium chloride, tetramethylammonium bromide, tetramethylammonium iodide, tetraethylammonium chloride, tetraethylammonium bromide, tetraethylammonium iodide ammonium, tetrapropylammonium chloride, tetrapropylammonium bromide, tetrapropylammonium iodide, tetrabutylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide, tetrabutylammonium iodide, trialkylbenzylammonium halide is selected from trimethylbenzylammonium chloride, trimethylbenzylammonium bromide, trimethylbenzylammonium iodide, triethylbenzylammonium chloride, triethylbenzylammonium bromide, triethylbenzylammonium iodide; the ring closing agent is selected from alkali metal hydroxide, alkali metal hydroxide aqueous solution, alkali metal hydroxide C 1-4 Alcohol solution, alkali metal C 1-6 The alkoxide and alkali metal carbonate are specifically selected from at least one of lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, lithium methoxide, sodium methoxide, potassium methoxide, sodium ethoxide, potassium ethoxide, sodium isopropoxide, potassium isopropoxide, sodium tert-butoxide, potassium tert-butoxide, sodium isopentanolate, potassium isopentanolate, sodium carbonate, and potassium carbonate, preferably an aqueous sodium hydroxide solution.

[0016] In a specific embodiment, the mass ratio of the pentadecylphenol extract to the halogenated epoxypropane in (2) is 1:(1.35-2.95).

[0017] By adopting the above technical solution, pentadecylphenol extract and halogenated propylene oxide within a certain ratio range can make propylene oxide more smoothly etherified and ring-closed to generate the target product, reduce the probability of side reactions, and improve the yield of the target product.

[0018] In a specific embodiment, the proton acid in (3) is selected from at least one of hydrochloric acid, sulfuric acid, phosphoric acid, and nitric acid, preferably at least one of hydrochloric acid and phosphoric acid; solvent 1 is an alcohol, alkyl ether alcohol, or ketone having a boiling point of 60-150°C; solvent 2 is one or more of toluene, xylene, and methylcyclohexane; and the neutralizing agent is one or a mixture of two or more of alkali metal hydroxides and their aqueous solutions or alcoholic solutions, alkali metal carbonates and their aqueous solutions, alkali metal bicarbonates and their aqueous solutions, calcium oxide, and calcium hydroxide.

[0019] The 1,2-epoxyalkane in (4) includes at least one of ethylene oxide, propylene oxide or butylene oxide; the catalyst II is metallic potassium, potassium hydride, C 1-4 Potassium alkoxide (potassium methoxide, potassium ethoxide, potassium isopropoxide, potassium tert-butoxide, etc.) and the C 1-4 Potassium alkoxide C 1-4 At least one of an alcohol solution and potassium carbonate.

[0020] The nitrogen replacement in step (4) makes the oxygen content in the reactor lower than 500 ppm.

[0021] By adopting the above technical solution, the oxygen content in the system is controlled to prevent side reactions from occurring and affecting the polymerization efficiency. Through nitrogen protection, moisture, oxygen, etc. are prevented from affecting the purity and yield of the polymerization reaction.

[0022] On the other hand, the present application also provides a composite dispersion composition, which comprises the above-mentioned silicon powder dispersant and pentaerythritol C 12-22 Fatty acid esters; preferably, pentaerythritol C 12-22 Fatty acid esters include pentaerythritol stearate and pentaerythritol polyoxyethylene ether fatty acid ester.

[0023] In a specific embodiment, a silicon powder dispersant modified with a natural phenolic compound and pentaerythritol C 12-22 The mass ratio of fatty acid ester is (5-8):1.

[0024] By adopting the above technical solution, a silicon powder dispersant modified by natural phenolic compounds and pentaerythritol C in a certain proportion range are prepared. 12-22 The mixing of fatty acid esters can further improve the dispersion of silicon powder and prevent aggregation, which may be due to the 12-22 Fatty acid esters are more easily dispersed on the surface of silicon particles and wrap the silicon powder. The addition of pentaerythritol stearate achieves better defoaming performance.12-22 Under the action of the chain segments in the silicon powder dispersant modified by fatty acid esters and natural phenolic compounds, the silicon powder can be better infiltrated and dispersed in the cutting fluid, solving the problems of insufficient dispersion and silicon powder adhering to the surface of crystalline silicon.

[0025] In summary, this application includes at least one of the following beneficial technical effects: 1. The present application prepares a dispersant containing cardol-modified polyether. Since the cardol-modified polyether has long-chain polyoxyalkylene segments and pentadecyl segments at positions 1, 3, and 5, the long-chain distribution at the intervals can produce sufficient steric hindrance, which has a significant dispersing effect on silicon powder and prevents silicon powder from agglomerating or flocculating. The presence of the dipolyether segment improves the hydrophilicity, thereby improving the compatibility between the dispersant and water, which is beneficial to improving the wetting efficiency of silicon powder during cutting. On the other hand, the molecules of this structure are more tightly arranged, and the film formed on the liquid surface is not easily destroyed by external forces, thereby reducing the generation of bubbles. The dipolyether segment structure also improves the lubricity and permeability of the dispersant. The cutting liquid penetrates between the wire mesh and the silicon wafer, and between the wire mesh and the debris, forming a lubricating film, which reduces cutting damage, stress, and microcracks. The better permeability can reduce friction and reduce cutting resistance.

[0026] 2. The present application adjusts the content of side chain groups in the same polyoxyalkylene segment so that the dispersant has both good encapsulation of silicon powder and lubrication, penetration, and low foaming properties, thereby improving cutting accuracy; the optimization of the position and content of the side groups further enhances the above-mentioned comprehensive effects of the dispersant.

[0027] 3. The present application prepares a composite dispersion composition by using a silicon powder dispersant modified with a natural phenolic compound and pentaerythritol C in a certain ratio range. 12-22 The mixing of fatty acid esters can further improve the dispersion of silicon powder, prevent agglomeration, and solve the problem of insufficient dispersion and silicon powder adhering to the surface of crystalline silicon. DETAILED DESCRIPTION

[0028] In this application, epichlorohydrin was purchased from Shandong Haideng New Materials Co., Ltd.; tetraethylammonium bromide was purchased from McLean; magnesium silicate was purchased from Youmei New Materials (Hebei) Co., Ltd.; 1,2-ethylene oxide was purchased from Yangzi Petrochemical Co., Ltd.; decarboxylated cashew nut shell liquid was from Naisu Mozambique Company; pentaerythritol stearate was purchased from Hubei Watson Chemical Technology Co., Ltd.; other raw materials can be obtained commercially.

[0029] Example 1 A method for preparing a silicon powder dispersant modified by a natural phenolic compound comprises the following steps: (1) 5 kg of decarboxylated cashew nut shell oil was filtered through a filter, preheated to 180° C., and then subjected to three-stage molecular distillation to obtain a pentadecanol extract, wherein the first-stage distillation temperature was 200° C. and the vacuum degree was 10 Pa. The light phase of the first-stage molecular distillation entered the second-stage molecular distillation, the second-stage distillation temperature was 190° C. and the vacuum degree was 5 Pa. The heavy phase of the second-stage distillation entered the third-stage molecular distillation, the third-stage distillation temperature was 185° C. and the vacuum degree was 3 Pa. The heavy phase of the third-stage molecular distillation was the product, and finally 625 g of pentadecanol extract was obtained, of which cardol and 2-methyl cardol accounted for 52%; (2) 315 g of pentadecylphenol extract, 1.58 g of 40% aqueous solution of tetraethylammonium bromide (containing 0.63 g of tetraethylammonium bromide) and 555 g of epichlorohydrin were heated to 70°C for 1 h to undergo a ring-opening etherification reaction. 140 g of 50% aqueous sodium hydroxide solution was then added dropwise over a period of 2 h. The reaction temperature was controlled at 68°C during the addition. After the addition was complete, the reaction was continued at this temperature for 1 h. The vacuum was turned on to recover the excess epichlorohydrin. The vacuum degree and temperature were gradually increased to control the liquid level in the reactor to be in a slightly boiling state. The reaction was terminated when the final temperature reached 90°C and the vacuum degree reached -0.099 MPa. When no epichlorohydrin condensed out, the reaction was completed and filtered to obtain pentadecylphenol glycidyl ether. (3) 270 g of the above-obtained pentadecylphenol glycidyl ether was added with 9.0 g of 85% phosphoric acid, 36 g of deionized water, and 19.2 g of isopropyl alcohol. The mixture was refluxed at 100° C. for 2 h. After the epoxy value of the sample was measured to be lower than 0.003, the solvent was removed by vacuum pumping. 80 g of toluene and 120 g of deionized water were added, followed by a 50% potassium hydroxide solution. The pH value was adjusted to 7.0, and the mixture was stirred for 30 min. After standing for separation, the lower layer of waste water was drained, the upper layer of oil was taken out and heated to 100° C., and the solvent and water in the material were removed by vacuum pumping to obtain a hydrolyzed product of pentadecylphenol glycidyl ether.

[0030] (4) Add 206g of the hydrolyzate of 15-decylphenol glycerol ether and 3.3g of 25% potassium isopropoxide isopropanol solution into the high-pressure alkoxylation reactor and stir evenly, then heat to 90°C, vacuum dehydrate and isopropanol for 120min, take samples for testing, the water content is less than 0.1%, and nitrogen replacement is performed to make the oxygen content lower than 500ppm; after the nitrogen replacement is completed, the material in the reactor is heated to 125°C, 480g of ethylene oxide and 400g of propylene oxide are continuously added to react, and the temperature in the reactor is controlled to be stable at 130°C and the pressure is lower than 0.45MPa during the addition of 1,2-epoxyalkylene. After all the inputs are completed, heat to 135°C, keep warm and mature for 2h, cool to 100°C, and vacuum degas for 10 minutes. Add 20g of deionized water and 1.0g of 85% phosphoric acid, stir for 30 minutes, then add 0.4g of magnesium silicate, heat to 110°C, vacuum dehydrate to a water content of ≤0.1%, add 0.4g of diatomaceous earth, filter and remove the generated phosphate to obtain a silicon powder dispersant modified by a natural phenolic compound.

[0031] Example 2 A method for preparing a silicon powder dispersant modified by a natural phenolic compound comprises the following steps: (1) 10 kg of decarboxylated cashew nut shell oil was filtered through a filter, preheated to 180 ° C, and then subjected to a four-stage molecular distillation to obtain a pentadecanol extract, wherein the first-stage distillation temperature was 205 ° C, the vacuum degree was 20 Pa, the light phase from the first-stage molecular distillation entered a second-stage molecular distiller, the second-stage distillation temperature was 195 ° C, the vacuum degree was 10 Pa, the heavy phase from the second-stage molecular distillation entered a third-stage molecular distiller, the third-stage distillation temperature was 190 ° C, the vacuum degree was 10 Pa, the heavy phase from the third-stage molecular distillation entered a fourth-stage molecular distiller, the fourth-stage distillation temperature was 180 ° C, the vacuum degree was 5 Pa, and the heavy phase from the fourth-stage molecular distillation was the product, and finally 600 g of pentadecanol extract was obtained, of which cardol and 2-methyl cardol accounted for 75%; (2) Take 315g of pentadecylphenol extract, 4.08g of 33% aqueous solution of benzyltriethylammonium bromide (containing 1.36g of benzyltriethylammonium bromide) and 880g of epichlorohydrin, heat to 80℃ for etherification reaction for 1h, cool to 70℃, and continuously add 166g of 50% sodium hydroxide aqueous solution dropwise within 3h, control the reaction temperature at 70℃ during the addition, and continue to keep the temperature for 1h. Turn on the vacuum to recover excess epichlorohydrin, gradually increase the vacuum degree and temperature to control the liquid level in the reactor to be in a slightly boiling state, wait until the final temperature reaches 85℃, the vacuum degree reaches -0.099MPa, and no epichlorohydrin condenses out, the reaction is completed, and filter to obtain pentadecylphenol glycidyl ether; (3) 270 g of the above-obtained pentadecylphenol glycidyl ether was added with 9.0 g of 85% phosphoric acid, 36 g of deionized water, and 19.2 g of isopropyl alcohol. The mixture was refluxed at 100° C. for 2 h. A sample was taken to measure the epoxy value. When the epoxy value was lower than 0.003, 100 g of methylcyclohexane and 120 g of deionized water were added. 50% potassium hydroxide solution was then added to adjust the pH to 7.0. The mixture was stirred for 30 min. After standing for separation, the upper layer of oil was extracted and heated to 105° C. The solvent and residual water in the material were removed under vacuum to obtain a hydrolyzed product of pentadecylphenol glycidyl ether. (4) 206 g of the hydrolyzate of 15-hydroxy phenol glycerol ether and 3.45 g of a 30% potassium methoxide methanol solution were added to a high-pressure alkoxylation reactor, stirred for 5 minutes, and then heated to 100° C., vacuum-dried for 120 minutes, and sampled for testing. The water content was less than 0.1%. Nitrogen replacement was performed to reduce the oxygen content to less than 500 ppm. After the nitrogen replacement was completed, the materials in the reactor were heated to 135° C., 480 g of ethylene oxide was continuously added, and then 400 g of butylene oxide was continuously added for reaction. During the entire feeding period, the temperature in the reactor was controlled to be stable at 130° C. and the pressure was lower than 0.45 MPa. After the feeding was completed, the temperature was kept at 130° C. for 4 hours, then cooled to 100° C., vacuum-dried for 30 minutes, and then 20 g of deionized water and 1.7 g of butylene oxide were added. 85% phosphoric acid, stirred for 30 minutes, then added 0.4g of magnesium silicate, heated to 110°C, vacuum dehydrated to a water content of ≤0.1%, added 0.4g of diatomaceous earth, filtered to remove the generated phosphate, and obtained a silicon powder dispersant modified based on natural phenolic compounds.

[0032] Example 3 A method for preparing a silicon powder dispersant modified by a natural phenolic compound comprises the following steps: (1) 10 kg of decarboxylated cashew nut shell oil was filtered through a filter, preheated to 180 ° C, and then subjected to a four-stage molecular distillation to obtain a pentadecanol extract, wherein the first-stage distillation temperature was 205 ° C, the vacuum degree was 15 Pa, the light phase from the first-stage molecular distillation entered a second-stage molecular distiller, the second-stage distillation temperature was 195 ° C, the vacuum degree was 12 Pa, the heavy phase from the second-stage molecular distillation entered a third-stage molecular distiller, the third-stage distillation temperature was 190 ° C, the vacuum degree was 6 Pa, the heavy phase from the third-stage molecular distillation entered a fourth-stage molecular distiller, the fourth-stage distillation temperature was 185 ° C, the vacuum degree was 3 Pa, and the heavy phase from the fourth-stage molecular distillation was the product, and finally 450 g of a pentadecanol extract was obtained, of which cardol and 2-methyl cardol accounted for 89%; (2) Take 315g of pentadecylphenol extract, 4.08g of 33% aqueous solution of benzyltriethylammonium bromide (containing 1.36g of benzyltriethylammonium bromide) and 880g of epichlorohydrin, heat to 80℃ for etherification reaction for 1h, cool to 70℃, and continuously add 166g of 50% sodium hydroxide aqueous solution dropwise within 3h, control the reaction temperature at 70℃ during the addition, and continue to keep the temperature for 1h. Turn on the vacuum to recover excess epichlorohydrin, gradually increase the vacuum degree and temperature to control the liquid level in the reactor to be in a slightly boiling state, wait until the final temperature reaches 85℃, the vacuum degree reaches -0.099MPa, and no epichlorohydrin condenses out, the reaction is completed, and filter to obtain pentadecylphenol glycidyl ether; (3) 270 g of the above-obtained pentadecanol glyceryl ether was added with 9.0 g of 85% phosphoric acid, 36 g of deionized water, and 19.2 g of isopropyl alcohol. The mixture was refluxed at 100° C. for 2 h. A sample was taken to measure the epoxy value. When the epoxy value was lower than 0.003, 100 g of methylcyclohexane and 120 g of deionized water were added. Then, 50% potassium hydroxide solution was added to adjust the pH value to 7.0. The mixture was stirred for 30 min. After standing for separation, the upper layer of oil was extracted and heated to 105° C. The solvent and residual water in the material were removed under vacuum to obtain the hydrolyzed product of pentadecanol glyceryl ether.

[0033] (4) 206 g of the hydrolyzate of 15-hydroxy phenol glycerol ether and 3.45 g of 30% potassium methoxide methanol solution were added to a high-pressure alkoxylation reactor, stirred for 5 minutes, and then heated to 100 ° C., vacuum-dried and dehydrated with methanol for 120 minutes, sampled and tested, the water content was less than 0.1%, and nitrogen replacement was performed to make the oxygen content lower than 500 ppm; after the nitrogen replacement was completed, the materials in the reactor were heated to 135 ° C., 480 g of ethylene oxide was continuously added, and then 400 g of propylene oxide was continuously added to react. During the entire feeding period, the temperature in the reactor was controlled to be stable at 130 ° C. and the pressure was lower than 0.3 MPa. After the feeding was completed, the temperature was kept at 130 ° C. for 4 hours, then cooled to 100 ° C., vacuum-dried and degassed for 30 minutes, and then 20 g of deionized water and 1.7 g of propylene oxide were added. 85% phosphoric acid, stirred for 30 minutes, then added 0.4g of magnesium silicate, heated to 110°C, vacuum dehydrated to a water content of ≤0.1%, added 0.4g of diatomaceous earth, filtered to remove the generated phosphate, and obtained a silicon powder dispersant modified based on natural phenolic compounds.

[0034] Example 4 A method for preparing a silicon powder dispersant modified by a natural phenolic compound comprises the following steps: (1) 10 kg of decarboxylated cashew nut shell oil was filtered through a filter, preheated to 180 ° C, and then subjected to a four-stage molecular distillation to obtain a pentadecanol extract, wherein the first-stage distillation temperature was 205 ° C, the vacuum degree was 15 Pa, the light phase from the first-stage molecular distillation entered a second-stage molecular distiller, the second-stage distillation temperature was 195 ° C, the vacuum degree was 12 Pa, the heavy phase from the second-stage molecular distillation entered a third-stage molecular distiller, the third-stage distillation temperature was 190 ° C, the vacuum degree was 6 Pa, the heavy phase from the third-stage molecular distillation entered a fourth-stage molecular distiller, the fourth-stage distillation temperature was 185 ° C, the vacuum degree was 3 Pa, and the heavy phase from the fourth-stage molecular distillation was the product, and finally 450 g of a pentadecanol extract was obtained, of which cardol and 2-methyl cardol accounted for 89%; (2) Take 315g of pentadecylphenol extract, 4.08g of 33% aqueous solution of benzyltriethylammonium bromide (containing 1.36g of benzyltriethylammonium bromide) and 666g of epichlorohydrin, heat to 80℃ for etherification reaction for 1h, cool to 70℃, and continuously add 166g of 50% sodium hydroxide aqueous solution dropwise within 3h, controlling the reaction temperature at 70℃ during the addition. After the addition is complete, continue to keep the temperature for 1h, start vacuum to recover excess epichlorohydrin, gradually increase the vacuum degree and temperature to control the liquid level in the reactor to be in a slightly boiling state, wait until the final temperature reaches 85℃, the vacuum degree reaches -0.099MPa, and no epichlorohydrin condenses out, the reaction is completed, and filter to obtain pentadecylphenol glycidyl ether; (3) 270 g of the above-obtained pentadecylphenol glycidyl ether was added with 9.0 g of 85% phosphoric acid, 36 g of deionized water, and 19.2 g of isopropyl alcohol. The mixture was refluxed at 100° C. for 2 h. A sample was taken to measure the epoxy value. When the epoxy value was lower than 0.003, 100 g of methylcyclohexane and 120 g of deionized water were added. 50% potassium hydroxide solution was then added to adjust the pH to 7.0. The mixture was stirred for 30 min. After standing for separation, the upper layer of oil was extracted and heated to 105° C. The solvent and residual water in the material were removed under vacuum to obtain a hydrolyzed product of pentadecylphenol glycidyl ether. (4) Add 206g of the hydrolyzate of 15-hydroxy phenol glycerol ether and 3.45g of 30% potassium methoxide methanol solution into a high-pressure alkoxylation reactor, stir for 5 minutes, heat to 100°C, vacuum dehydrate and methanol for 120min, take samples for detection, the water content is less than 0.1%, and nitrogen replacement is performed to make the oxygen content lower than 500ppm; after the nitrogen replacement is completed, the materials in the reactor are heated to 135°C, 400g of ethylene oxide, 80g of butylene oxide, 80g of ethylene oxide, and 400g of butylene oxide are added in batches for reaction. During the entire feeding period, the temperature in the reactor is controlled to be stable at 130°C and the pressure is lower than 0.45MPa. After the feeding is completed, continue to keep the temperature at 130°C for 4h, cool to 100°C, vacuum degas for 30 minutes, and then add 20g of deionized water, 1.7g of 85% phosphoric acid, stirred for 30 minutes, then added 0.4g of magnesium silicate, heated to 110°C, vacuum dehydrated to a water content of ≤0.1%, added 0.4g of diatomaceous earth, filtered to remove the generated phosphate, and obtained a silicon powder dispersant modified based on natural phenolic compounds.

[0035] Example 5 A composite dispersion composition was prepared by adding pentaerythritol stearate to 100 g of the silicon powder dispersant prepared by the method of Example 4 so that the mass ratio of the silicon powder dispersant modified based on natural phenolic compounds and pentaerythritol stearate was 8:1. The mixture was mixed and stirred for 45 minutes to obtain a silicon powder dispersant modified based on natural phenolic compounds.

[0036] Example 6 Composite dispersion composition, pentaerythritol stearate was added to 100g of the silicon powder dispersant prepared by the method of Example 4, so that the mass ratio of the silicon powder dispersant modified based on natural phenolic compounds to pentaerythritol stearate was 4:1, and the mixture was stirred for 45 minutes to obtain a silicon powder dispersant modified based on natural phenolic compounds. Example 7 Composite dispersion composition, pentaerythritol stearate was added to 100g of the silicon powder dispersant prepared by the method of Example 4, so that the mass ratio of the silicon powder dispersant modified based on natural phenolic compounds to pentaerythritol stearate was 12:1, and the mixture was stirred for 45 minutes to obtain a silicon powder dispersant modified based on natural phenolic compounds. Comparative Example 1: A method for preparing a silicon powder dispersant modified by a natural cardanol compound comprises the following steps: (1) taking the light phase obtained from the secondary molecular distillation in Example 3, i.e., cardanol (cardanol content reaches 94%) for later use; (2) Take 315g of pentadecylphenol extract, 4.08g of 33% aqueous solution of benzyltriethylammonium bromide (containing 1.36g of benzyltriethylammonium bromide) and 880g of epichlorohydrin, heat to 80℃ for etherification reaction for 1h, cool to 70℃, and continuously add 166g of 50% sodium hydroxide aqueous solution dropwise within 3h, control the reaction temperature at 70℃ during the addition, and continue to keep the temperature for 1h. Turn on the vacuum to recover excess epichlorohydrin, gradually increase the vacuum degree and temperature to control the liquid level in the reactor to be in a slightly boiling state, wait until the final temperature reaches 85℃, the vacuum degree reaches -0.099MPa, and no epichlorohydrin condenses out, the reaction is completed, and filter to obtain pentadecylphenol glycidyl ether; (3) 270 g of the above-obtained pentadecylphenol glycidyl ether was added with 9.0 g of 85% phosphoric acid, 36 g of deionized water, and 19.2 g of isopropyl alcohol. The mixture was refluxed at 100° C. for 2 h. A sample was taken to measure the epoxy value. When the epoxy value was lower than 0.003, 100 g of methylcyclohexane and 120 g of deionized water were added. 50% potassium hydroxide solution was then added to adjust the pH to 7.0. The mixture was stirred for 30 min. After standing for separation, the upper layer of oil was extracted and heated to 105° C. The solvent and residual water in the material were removed under vacuum to obtain a hydrolyzed product of pentadecylphenol glycidyl ether. (4) 206 g of the hydrolyzate of 15-hydroxy phenol glycerol ether and 3.45 g of a 30% potassium methoxide methanol solution were added to a high-pressure alkoxylation reactor, stirred for 5 minutes, and then heated to 100° C., vacuum-dried for 120 minutes, and sampled for testing. The water content was less than 0.1%. Nitrogen replacement was performed to reduce the oxygen content to less than 500 ppm. After the nitrogen replacement was completed, the materials in the reactor were heated to 135° C., 480 g of ethylene oxide was continuously added, and then 400 g of butylene oxide was continuously added for reaction. During the entire feeding period, the temperature in the reactor was controlled to be stable at 130° C. and the pressure was lower than 0.45 MPa. After the feeding was completed, the temperature was kept at 130° C. for 4 hours, then cooled to 100° C., vacuum-dried for 30 minutes, and then 20 g of deionized water and 1.7 g of butylene oxide were added. 85% phosphoric acid, stirred for 30 minutes, then added 0.4g of magnesium silicate, heated to 110°C, vacuum dehydrated to a water content of ≤0.1%, added 0.4g of diatomaceous earth, filtered to remove the generated phosphate, and obtained a silicon powder dispersant modified based on natural phenolic compounds.

[0037] Comparative Example 2 A method for preparing a silicon powder dispersant modified by a natural phenolic compound comprises the following steps: (1) 10 kg of decarboxylated cashew nut shell oil was filtered through a filter, preheated to 180 ° C, and then subjected to a four-stage molecular distillation to obtain a pentadecanol extract, wherein the first-stage distillation temperature was 205 ° C, the vacuum degree was 15 Pa, the light phase from the first-stage molecular distillation entered a second-stage molecular distiller, the second-stage distillation temperature was 195 ° C, the vacuum degree was 12 Pa, the heavy phase from the second-stage molecular distillation entered a third-stage molecular distiller, the third-stage distillation temperature was 190 ° C, the vacuum degree was 6 Pa, the heavy phase from the third-stage molecular distillation entered a fourth-stage molecular distiller, the fourth-stage distillation temperature was 185 ° C, the vacuum degree was 3 Pa, and the heavy phase from the fourth-stage molecular distillation was the product, and finally 450 g of a pentadecanol extract was obtained, of which cardol and 2-methyl cardol accounted for 89%; (2) Take 315g of pentadecylphenol extract, 4.08g of 33% aqueous solution of benzyltriethylammonium bromide (containing 1.36g of benzyltriethylammonium bromide) and 880g of epichlorohydrin, heat to 80℃ for etherification reaction for 1h, cool to 70℃, and continuously add 166g of 50% sodium hydroxide aqueous solution dropwise within 3h, control the reaction temperature at 70℃ during the addition, and continue to keep the temperature for 1h. Turn on the vacuum to recover excess epichlorohydrin, gradually increase the vacuum degree and temperature to control the liquid level in the reactor to be in a slightly boiling state, wait until the final temperature reaches 85℃, the vacuum degree reaches -0.099MPa, and no epichlorohydrin condenses out, the reaction is completed, and filter to obtain pentadecylphenol glycidyl ether; (3) 270 g of the above-obtained pentadecylphenol glycidyl ether was added with 9.0 g of 85% phosphoric acid, 36 g of deionized water, and 19.2 g of isopropyl alcohol. The mixture was refluxed at 100° C. for 2 h. A sample was taken to measure the epoxy value. When the epoxy value was lower than 0.003, 100 g of methylcyclohexane and 120 g of deionized water were added. 50% potassium hydroxide solution was then added to adjust the pH to 7.0. The mixture was stirred for 30 min. After standing for separation, the upper layer of oil was extracted and heated to 105° C. The solvent and residual water in the material were removed under vacuum to obtain a hydrolyzed product of pentadecylphenol glycidyl ether. (4) 206 g of the hydrolyzate of pentadecanol glycerol ether and 3.45 g of a 30% potassium methoxide methanol solution were added to a high-pressure alkoxylation reactor, stirred for 5 minutes, and then heated to 100° C., vacuum-dried for 120 minutes, and sampled for testing. The water content was less than 0.1%. Nitrogen replacement was performed to reduce the oxygen content to less than 500 ppm. After nitrogen replacement, the materials in the reactor were heated to 135° C., and 880 g of ethylene oxide was continuously added for reaction. During the entire addition period, the temperature in the reactor was kept stable at 130° C., and the pressure was less than 0.45 MPa. After the addition was completed, the reactor was kept warm at 130° C. for 4 hours, cooled to 100° C., vacuum-dried for 30 minutes, and then 20 g of deionized water and 1.7 g of ethylene oxide were added. 85% phosphoric acid, stirred for 30 minutes, then added 0.4g of magnesium silicate, heated to 110°C, vacuum dehydrated to a water content of ≤0.1%, added 0.4g of diatomaceous earth, filtered to remove the generated phosphate, and obtained a silicon powder dispersant modified based on natural phenolic compounds.

[0038] Comparative Example 3 A method for preparing a silicon powder dispersant modified by a natural phenolic compound comprises the following steps: (1) 10 kg of decarboxylated cashew nut shell oil was filtered through a filter, preheated to 180 ° C, and then subjected to a four-stage molecular distillation to obtain a pentadecanol extract, wherein the first-stage distillation temperature was 205 ° C, the vacuum degree was 15 Pa, the light phase from the first-stage molecular distillation entered a second-stage molecular distiller, the second-stage distillation temperature was 195 ° C, the vacuum degree was 12 Pa, the heavy phase from the second-stage molecular distillation entered a third-stage molecular distiller, the third-stage distillation temperature was 190 ° C, the vacuum degree was 6 Pa, the heavy phase from the third-stage molecular distillation entered a fourth-stage molecular distiller, the fourth-stage distillation temperature was 185 ° C, the vacuum degree was 3 Pa, and the heavy phase from the fourth-stage molecular distillation was the product, and finally 450 g of a pentadecanol extract was obtained, of which cardol and 2-methyl cardol accounted for 89%; (2) Take 315g of pentadecylphenol extract, 4.08g of 33% aqueous solution of benzyltriethylammonium bromide (containing 1.36g of benzyltriethylammonium bromide) and 880g of epichlorohydrin, heat to 80℃ for etherification reaction for 1h, cool to 70℃, and continuously add 166g of 50% sodium hydroxide aqueous solution dropwise within 3h, control the reaction temperature at 70℃ during the addition, and continue to keep the temperature for 1h. Turn on the vacuum to recover excess epichlorohydrin, gradually increase the vacuum degree and temperature to control the liquid level in the reactor to be in a slightly boiling state, wait until the final temperature reaches 85℃, the vacuum degree reaches -0.099MPa, and no epichlorohydrin condenses out, the reaction is completed, and filter to obtain pentadecylphenol glycidyl ether; (3) 270 g of the above-obtained pentadecylphenol glycidyl ether was added with 9.0 g of 85% phosphoric acid, 36 g of deionized water, and 19.2 g of isopropyl alcohol. The mixture was refluxed at 100° C. for 2 h. A sample was taken to measure the epoxy value. When the epoxy value was lower than 0.003, 100 g of methylcyclohexane and 120 g of deionized water were added. 50% potassium hydroxide solution was then added to adjust the pH to 7.0. The mixture was stirred for 30 min. After standing for separation, the upper layer of oil was extracted and heated to 105° C. The solvent and residual water in the material were removed under vacuum to obtain a hydrolyzed product of pentadecylphenol glycidyl ether. (4) 206 g of the hydrolyzate of pentadecanol glycerol ether and 3.45 g of a 30% potassium methoxide methanol solution were added to a high-pressure alkoxylation reactor, stirred for 5 minutes, and then heated to 100° C., vacuum-dried and dehydrated with methanol for 120 minutes. Samples were taken for testing, and the water content was less than 0.1%. Nitrogen replacement was performed to reduce the oxygen content to less than 500 ppm. After nitrogen replacement was completed, the materials in the reactor were heated to 135° C., and 880 g of butylene oxide was continuously added for reaction. During the entire addition period, the temperature in the reactor was kept stable at 130° C. and the pressure was less than 0.45 MPa. After the addition was completed, the reactor was kept warm at 130° C. for 4 hours, cooled to 100° C., vacuum-dried and degassed for 30 minutes, and then 20 g of deionized water and 1.7 g of butylene oxide were added. 85% phosphoric acid, stirred for 30 minutes, then added 0.4g of magnesium silicate, heated to 110°C, vacuum dehydrated to a water content of ≤0.1%, added 0.4g of diatomaceous earth, filtered to remove the generated phosphate, and obtained a silicon powder dispersant modified based on natural phenolic compounds.

[0039] Performance testing A silicon powder dispersant and a composite dispersing composition modified with a natural phenolic compound prepared in the examples and comparative examples were added to deionized water to prepare a 30% cutting fluid, and the same size silicon wafers were cut in the same cutting machine for testing; Table 1 Performance Test Results As can be seen from Table 1, the dispersant and composite dispersion composition of the present application have comprehensive properties such as dispersing silicon wafers, lubrication, and penetration, which are beneficial to cutting and can achieve excellent comprehensive effects when used in diamond wire cutting fluids. It can be seen from Examples 1-3 that with the increase in the content of cardol-modified polyether, the effect of the cutting fluid is greatly improved, which may be due to the good wettability, permeability, and lubricity of cardol-modified polyether for silicon powder; it can be seen from Example 1 and Comparative Examples 2-3 that the present application can improve the cutting effect by preparing polyether segments with specific side chain groups; and Example 4 further improves the dispersing effect of the dispersant on silicon powder and debris by adjusting the group position, which is beneficial to cutting; Examples 5-7 show that the dispersed composite composition of the present application can further improve the dispersing and wetting effect on silicon powder, and it can be seen from Example 1 and Comparative Example 1 that the cardol-modified polyether is superior to the cardanol-modified polyether in the dispersion process.

[0040] The above are all preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A silicon powder dispersant modified by natural phenolic compounds, characterized in that: The dispersant includes cardol modified polyether, and its structural formula is as shown in Formula I: In Formula I, R 1 C 15 H 25 -、C 15 H 27 -、C 15 H 29 -、C 15 H 31 - at least one straight-chain hydrocarbon structure; R 2 is H- or CH3-; (A 1 O)m and (A 2 O)n is a homopolyoxyalkylene segment, A 1 Including -CH2CH2-, -CH2CH(CH3)- or -CH2CH(CH2CH3)-, -CH2CH2O- in the whole (A 1 O)m polyoxyalkylene chain segments account for 50%-100%, and m is an integer of 2-50; A 2 Including -CH2CH2-, -CH2CH(CH3)- or -CH2CH(CH2CH3)-, -CH2CH2O- in the whole (A 2 O)n polyoxyalkylene chain segments account for 0-50%; n is an integer of 2-50.

2. The silicon powder dispersant modified by natural phenolic compounds according to claim 1, characterized in that: The preparation method of the dispersant comprises the following steps: (1) obtaining a pentadecylphenol extract by multi-stage molecular distillation of cashew nut shell oil; (2) taking a pentadecylphenol extract, adding a catalyst I and a halopropylene oxide to carry out an etherification reaction, then adding a ring-closing agent, continuing the reaction, and purifying to obtain pentadecylphenol glycidyl ether; (3) taking the above-mentioned pentadecylphenol glycidyl ether, adding protonic acid, deionized water and solvent, and reacting to obtain a hydrolyzate of pentadecylphenol glycidyl ether; (4) The hydrolyzate of the pentadecylphenol glycerol ether and the catalyst II are stirred evenly, dehydrated, replaced with nitrogen, and 1,2-epoxyalkylene is added to react, and then post-treated to obtain a silicon powder dispersant modified by a natural phenolic compound.

3. The silicon powder dispersant modified by natural phenolic compounds according to claim 2, characterized in that: The total amount of cardol and 2-methyl cardol in the pentadecylphenol extract of (1) accounts for 50-90% of the total amount of the extract.

4. The silicon powder dispersant modified by natural phenolic compounds according to claim 2, characterized in that: The mass ratio of the pentadecylphenol extract to the halogenated epoxypropane in (2) is 1:(1.35-2.95).

5. The silicon powder dispersant modified by natural phenolic compounds according to claim 2, characterized in that: The solvent in (3) is an alcohol, an alkyl ether alcohol or a ketone having a boiling point of 60-150°C.

6. The silicon powder dispersant modified by natural phenolic compounds according to claim 2, characterized in that: The 1,2-alkylene oxide in (4) includes at least one of ethylene oxide, propylene oxide or butylene oxide.

7. A composite dispersed composition, characterized in that: The composite composition comprises the silicon powder dispersant modified by natural phenolic compounds according to any one of claims 1 to 6 and pentaerythritol C 12-22 Fatty acid esters.

8. A composite dispersion composition according to claim 7, characterized in that: Silica powder dispersant modified by natural phenolic compounds and pentaerythritol C 12-22 The mass ratio of fatty acid lipids is (5-8):1.

Images