Preparation methods and applications of methyl ethyl ketone peroxide

Abstract

This invention relates to the field of methyl ethyl ketone peroxide (MEKP) production technology, specifically to a method for preparing MEKP and its applications. The method includes the following steps: adding [BMIM]PF6 ionic liquid to a reaction vessel, followed by a composite catalyst, triethyl borate, and MEKP; cooling and then adding H2O2 dropwise, heating to 20-30°C, and adding a MnHCF dispersion; cooling the reaction solution to crystallize, and filtering to obtain preliminary MEKP crystals; recovering the ionic liquid by vacuum distillation of the filtrate; dehydrating the solution using a vacuum membrane; adding polyurethane acrylate and DPGDA, then coating the solution with a gelatin-gum arabic wall material, and spray drying to obtain MEKP. This invention effectively solves the core pain points in MEKP production and applications through triple innovation: MnHCF bimetallic catalysis, borate ester stabilization, and microcapsule safety design. It demonstrates significant advantages in catalytic efficiency, storage stability, safety performance, and practical applications.

Description

Technical Field

[0001] This invention relates to the field of methyl ethyl ketone peroxide production technology, specifically to the preparation method and application of methyl ethyl ketone peroxide. Background Technology

[0002] Methyl ethyl ketone peroxide (MEKP) plays a crucial role in the field of materials synthesis as a core curing initiator for unsaturated polyester resins (UPRs). It initiates polymerization reactions by generating free radicals through decomposition, and its active oxygen content (AO%), low-temperature initiation efficiency, and storage stability are important technical indicators for evaluating its performance, directly affecting subsequent application results.

[0003] Current production technologies face multiple challenges. In terms of catalytic efficiency, traditional CeO2 catalysts suffer from slow reaction rates and long gel times due to weak electron transfer capabilities, and the presence of significant metal residues can cause yellowing of the stone, affecting the product's appearance. Regarding storage stability, the reactive and easily broken peroxide bonds result in an AO% decay rate exceeding 5% within 30 days, severely limiting the product's storage life and transportation range. In terms of safety, liquid MEKP has an impact sensitivity of only 2-3 J, posing a high safety risk during transportation and handling, potentially leading to accidents.

[0004] In practical applications, the shortcomings of existing technologies are also quite obvious. For thick-section materials, the exothermic peak temperature during curing is below 170℃, resulting in insufficient internal curing of the stone and affecting the overall structural strength and stability. In high-filler systems, the moisture and metal ions contained in the filler can interfere with the initiation process, causing the bubble defect rate to exceed 3%, reducing the product's pass rate and performance, and making it difficult to meet the needs of high-end application scenarios. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a method for preparing methyl ethyl ketone peroxide (MEKP). Through the triple innovation of MnHCF bimetallic catalysis, borate ester stabilization, and microcapsule safety design, the core pain points in MEKP production and application are effectively solved, and significant advantages are shown in catalytic efficiency, storage stability, safety performance and practical application.

[0006] The purpose of this invention is to provide an application of methyl ethyl ketone peroxide for the production of artificial stone, particularly for the preparation of quartz stone slabs, calcium stone slabs, and composite aluminum stone slabs.

[0007] This invention is achieved using the following technical solution:

[0008] The method for preparing methyl ethyl ketone peroxide includes the following steps:

[0009] (1) Add [BMIM]PF6 ionic liquid to the reactor, followed by the addition of composite catalyst, triethyl borate and methyl ethyl ketone;

[0010] (2) Cool down to 1-10℃, add H2O2 dropwise over 2-2.5 hours, and keep the temperature ≤15℃;

[0011] (3) Heat to 20-30℃, add MnHCF dispersion, and stir at 600rpm for 1.5-2.5 hours;

[0012] (4) Cool the reaction solution to -20 to -10℃ and crystallize for 8-9 hours. Filter to obtain preliminary crystals of methyl ethyl ketone peroxide. Distill the filtrate under reduced pressure to recover the ionic liquid. Dehydrate the preliminary crystals of methyl ethyl ketone peroxide under vacuum membrane until the moisture content is ≤0.2%. After adding polyurethane acrylate and DPGDA, coat the mixture with gelatin-gum arabic wall material and spray dry to obtain methyl ethyl ketone peroxide. Before spray drying, mix polyurethane acrylate, DPGDA and MEKP crystals, add gelatin-gum arabic aqueous solution, the mass ratio of gelatin to gum arabic is 1:1.2, and the total solid content of the coating solution is 15wt%.

[0013] The composite catalyst is an Amberlyst-15 / HPW composite support.

[0014] The molar ratio of H2O2 to methyl ethyl ketone is 1:(1.05-1.15); the amount of composite catalyst added is 2.0-5.0 wt% of the mass of methyl ethyl ketone; the amount of triethyl borate added is 0.1-0.3 wt% of the mass of methyl ethyl ketone; the amount of MnHCF dispersion added is 0.2-0.4 wt% of the mass of methyl ethyl ketone; the amount of polyurethane acrylate added is 2.0-4.0 wt% of the mass of methyl ethyl ketone; the amount of DPGDA added is 4.0-6.0 wt% of the mass of methyl ethyl ketone; and the amount of [BMIM]PF6 ionic liquid added is 8-12 vol% of the reactor volume.

[0015] The preparation method of the composite catalyst includes the following steps:

[0016] ①Immerse the dried Amberlyst-15 resin in 50% HPW impregnation solution and let it stand while stirring;

[0017] ② Transfer to a Buchner funnel and evacuate until no more liquid drips;

[0018] ③ Heat the remaining impregnation solution to 60°C, add the carrier that has been suctioned, and stir.

[0019] ④ Filter out the support and pre-dry it under vacuum at 60-62℃; then transfer it to a vacuum drying oven at 110-112℃ for activation to obtain the composite catalyst.

[0020] The Amberlyst-15 resin has a particle size of 0.6-0.8 mm and an ion exchange capacity of ≥4.8 mmol / g; the HPW loading rate is 28-32 wt%.

[0021] Amberlyst-15 resin pretreatment: Wash three times with 10 times the volume of deionized water, and vacuum dry at 60℃ for 12 hours.

[0022] The chemical formula of phosphotungstic acid (HPW) is H3PW. 12 O 40 • xH2O, purity ≥99%; Impregnation solution preparation: weigh HPW powder at 30% of the dry weight of the carrier, dissolve in 200mL of deionized water, and ultrasonically disperse for 20min at a power of 500W.

[0023] In step ①, the mixture is left to stand at room temperature for 2 hours, and then stirred intermittently once every 30 minutes; in step ③, it is stirred at a constant temperature of 55-60℃ for 1-2 hours; in step ④, the activation time is 2-2.5 hours.

[0024] The method for preparing the MnHCF dispersion includes the following steps:

[0025] I. Pre-fill the reactor with deionized water, pump equal volumes of K4[Fe(CN)6] solution and manganese salt solution into the reactor, adjust the pH to 1.8-2.2, stir continuously, and continue the reaction for 25-35 minutes after the addition is complete;

[0026] II. Aging and crystallization: Heat to 58-62℃, stir and age for 22-26 hours, then centrifuge, wash with deionized water until conductivity ≤60μS / cm, and vacuum dry for 11-13 hours;

[0027] III. Hydrogen reduction activation: In an N2 / H2 atmosphere, the temperature is raised to 198-202℃, held at that temperature, and then cooled under N2 protection to obtain powder;

[0028] IV. Preparation of dispersion: The powder obtained in step III is mixed with anhydrous ethanol at a mass ratio of 1:9, magnetically stirred and then ultrasonically treated to obtain MnHCF dispersion.

[0029] The concentration of the K4[Fe(CN)6] solution is 0.08-0.12M; the raw material for the manganese salt solution is MnCl2·4H2O, with a concentration of 0.08-0.12M.

[0030] In step I, the reactor temperature is 24-26℃, and the pH is adjusted by adding HCl dropwise; in step III, the heating rate is 4-6℃ / min with a volume ratio of N2 / H2 = (94-96):(4-6), and the holding time is 1.8-2.2 hours.

[0031] In step II, the heating rate is 2℃ / min, the aging process is maintained with stirring at 200rpm, and the vacuum drying temperature is 60-62℃; in step IV, the ultrasonic treatment power is 200W, the frequency is 40kHz, the time is 10-20min, and the ice bath temperature is controlled at ≤30℃.

[0032] The aforementioned application of methyl ethyl ketone peroxide is for the production of artificial stone, preferably for the preparation of quartz stone slabs, calcium stone slabs, and composite aluminum stone slabs.

[0033] The MnHCF bimetallic catalytic system is used, and its Fe 3+ / Mn 2+ The -C≡N system lowers the activation energy of the reaction, enabling rapid initiation at low temperatures and shortening gelation time. Triethyl borate coordinates with the peroxy bond (-OO-) of methyl ethyl ketone peroxide through its electron-deficient boron atom, forming a stable BO coordination bond. Simultaneously, the steric hindrance of the ethoxy group shields the peroxy bond, reducing its breakage probability and increasing the thermal decomposition temperature of the peroxy bond by 18°C, thus reducing storage degradation. Microencapsulation of gelatin and gum arabic increases the impact sensitivity from 2J to 8J, reducing operational accident rates and achieving intrinsically safe design.

[0034] Compared with the prior art, the beneficial effects of the present invention are:

[0035] (1) This invention effectively solves the core pain points in the production and application of MEKP through triple innovation of MnHCF bimetallic catalysis, borate ester stabilization, and microcapsule safety design, demonstrating significant advantages in catalytic efficiency, storage stability, safety performance, and practical application. Regarding catalytic efficiency, the Fe of MnHCF... 3+ / Mn 2+ The -C≡N system lowers the activation energy of the reaction, enabling rapid initiation at low temperatures and shortening the gelation time to 11.5-13.2 min, a 148% improvement over traditional CeO₂ catalysts, thus significantly increasing production efficiency. Simultaneously, the catalyst system avoids the degradation of CeO₂. 3+ Metal ion residues, Mn 2+ With a residual content of ≤5ppm, the problem of yellowing in stone is solved, ensuring the product's appearance quality. Regarding storage stability, the BOO five-membered chelate ring formed by triethyl borate increases the peroxide bond breaking energy by 25%, reducing the 30-day AO% decay rate to below 1%, a 589% reduction compared to traditional phosphate ester additives. This significantly extends the product's shelf life and reduces performance loss during transportation and storage. Safety performance optimization is particularly outstanding; the gelatin-gum arabic microencapsulation treatment increases the impact sensitivity of MEKP from 2J to 8J, reducing the accident rate by 97%. The transportation and use risks of liquid MEKP are significantly reduced, meeting the stringent safety requirements of industrial production.

[0036] (2) The methyl ethyl ketone peroxide prepared by this invention has significant advantages when applied to the production of artificial stone. When used in quartz stone slabs, it can increase the bending strength by 43.7% and reduce the bubble defect rate by 96%. When used in calcium stone slabs, it can shorten the demolding time by 32.8% and achieve a texture clarity of level 5. When used in composite aluminum plate stone, it can reduce the operation accident rate by 97%, reduce the VOC emission by 88.2%, and reduce the overall cost by 25.8%. Detailed Implementation

[0037] To make the objectives and technical solutions of this invention clearer, the invention will be further described in detail below.

[0038] The following are the manufacturers of some of the raw materials used in the examples and comparative examples:

[0039] Phosphotungstic acid: purity ≥99%, Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0040] Amberlyst-15 resin: DuPont;

[0041] Triethyl borate: Bailingwei Technology Co., Ltd.;

[0042] Polyurethane acrylate: Functionality 3, ZX Resins (China) Co., Ltd.;

[0043] DPGDA (Dipropylene glycol diacrylate): Changxing Materials Industry Co., Ltd.

[0044] Gelatin: Rousselot (China) Gelatin Co., Ltd.;

[0045] Gum Arabic: Lectra GmbH, France;

[0046] UPR resin: DSM (China) Co., Ltd.;

[0047] K4[Fe(CN)6]: Sinopharm Chemical Reagent Co., Ltd.;

[0048] MnCl2·4H2O: Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0049] [BMIM]PF6 ionic liquid: Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences;

[0050] CeO2 nanoparticles: Evonik Industries, Germany;

[0051] 239: AkzoNobel;

[0052] M-50: Perstop Group.

[0053] Test method:

[0054] Active oxygen content (AO%): ASTM E298 / ISO 11357;

[0055] Gel time: ASTM D2471;

[0056] Half-life at 50°C: DSC method (ISO 11357-5);

[0057] Impact sensitivity: GB / T 21567 (drop hammer test);

[0058] Metal residues: ICP-OES (GB / T 23942);

[0059] Moisture content: Karl Fischer titration (GB / T 6283);

[0060] Electrical conductivity: GB / T 11007-2008;

[0061] Flexural strength: GB / T 9966.1;

[0062] Bubble defect rate: cross-sectional microscopic image analysis (ISO 11998);

[0063] Exothermic peak temperature: DSC curing curve (ISO 11357-5);

[0064] Demolding time: Viscosity mutation method (ASTM D4473);

[0065] Texture clarity: Visual rating (1-5, refer to ISO 1302);

[0066] Peel strength: GB / T 2790 (180° peel test);

[0067] Thermal cycling cracking rate: GB / T 35160 (-40℃-80℃, 20 cycles);

[0068] VOC emissions: ISO 16000 (climate chamber method).

[0069] Example 1

[0070] The preparation method of the composite catalyst includes the following steps:

[0071] ①Immerse the dried Amberlyst-15 resin in 50% HPW impregnation solution and let it stand while stirring;

[0072] ② Transfer to a Buchner funnel and evacuate until no more liquid drips;

[0073] ③ Heat the remaining impregnation solution to 60°C, add the carrier that has been suctioned, and stir.

[0074] ④ Filter out the carrier and pre-dry it under vacuum at 62℃; then transfer it to a vacuum drying oven at 112℃ for activation to obtain the composite catalyst.

[0075] The Amberlyst-15 resin has a particle size of 0.6 mm and an ion exchange capacity of 4.8 mmol / g; the HPW loading rate is 28 wt%.

[0076] Amberlyst-15 resin pretreatment: Wash three times with 10 times the volume of deionized water, and vacuum dry at 60℃ for 12 hours.

[0077] The purity of phosphotungstic acid (HPW) is 99%; impregnation solution preparation: weigh HPW powder at 30% of the dry weight of the carrier, dissolve it in 200mL of deionized water, and ultrasonically disperse it for 20min at a power of 500W.

[0078] In step ①, let it stand at room temperature for 2 hours, and stir intermittently once every 30 minutes; in step ③, stir at a constant temperature of 60℃ for 1 hour; in step ④, the activation time is 2.5 hours.

[0079] The method for preparing MnHCF dispersion includes the following steps:

[0080] I. Prefill the reactor with deionized water, pump equal volumes of K4[Fe(CN)6] solution and manganese salt solution into the reactor, adjust the pH to 1.8, stir continuously, and continue the reaction for 35 minutes after the addition is complete;

[0081] II. Aging and crystallization: Heat to 58℃, stir and age for 22 hours, then centrifuge, wash with deionized water until the conductivity is 60μS / cm, and vacuum dry for 11 hours;

[0082] III. Hydrogen reduction activation: In an N2 / H2 atmosphere, the temperature is raised to 202℃, held at that temperature, and then cooled under N2 protection to obtain powder;

[0083] IV. Preparation of dispersion: The powder obtained in step III is mixed with anhydrous ethanol at a mass ratio of 1:9, magnetically stirred and then ultrasonically treated to obtain MnHCF dispersion.

[0084] The concentration of the K4[Fe(CN)6] solution is 0.08M; the raw material for the manganese salt solution is MnCl2·4H2O, with a concentration of 0.08M.

[0085] In step I, the reactor temperature is 26℃, and the pH is adjusted by adding HCl dropwise; in step III, the heating rate is 6℃ / min at a volume ratio of N2 / H2=94:6, and the holding time is 2.2 hours.

[0086] In step II, the heating rate is 2℃ / min, the aging process is maintained with stirring at 200rpm, and the vacuum drying temperature is 62℃; in step IV, the ultrasonic treatment power is 200W, the frequency is 40kHz, the time is 20min, and the ice bath temperature is controlled at 30℃.

[0087] The preparation method of methyl ethyl ketone peroxide includes the following steps:

[0088] (1) Add [BMIM]PF6 ionic liquid to the reactor, followed by the addition of composite catalyst, triethyl borate and methyl ethyl ketone;

[0089] (2) Cool down to 1℃, add H2O2 dropwise over 2.5 hours, and control the temperature at 15℃;

[0090] (3) Heat to 30°C, add MnHCF dispersion, and stir at 600 rpm for 2.5 hours;

[0091] (4) The reaction solution was cooled to -10℃ and crystallized for 9 hours. The solution was filtered to obtain preliminary crystals of methyl ethyl ketone peroxide. The filtrate was distilled under reduced pressure to recover the ionic liquid. The preliminary crystals of methyl ethyl ketone peroxide were dehydrated under vacuum membrane to a moisture content of 0.2%. After adding polyurethane acrylate and DPGDA, the solution was coated with gelatin-gum arabic wall material and spray-dried to obtain methyl ethyl ketone peroxide. The mass ratio of gelatin to gum arabic was 1:1.2, and the total solid content of the coating solution was 15 wt%.

[0092] The composite catalyst is an Amberlyst-15 / HPW composite support.

[0093] The molar ratio of H2O2 to methyl ethyl ketone is 1:1.05; the amount of composite catalyst added is 2.0 wt% of the mass of methyl ethyl ketone; the amount of triethyl borate added is 0.1 wt% of the mass of methyl ethyl ketone; the amount of MnHCF dispersion added is 0.2 wt% of the mass of methyl ethyl ketone; the amount of polyurethane acrylate added is 2.0 wt% of the mass of methyl ethyl ketone; the amount of DPGDA added is 4.0 wt% of the mass of methyl ethyl ketone; and the amount of [BMIM]PF6 ionic liquid added is 8 vol of the reactor volume.

[0094] Example 2

[0095] The preparation method of the composite catalyst includes the following steps:

[0096] ①Immerse the dried Amberlyst-15 resin in 50% HPW impregnation solution and let it stand while stirring;

[0097] ② Transfer to a Buchner funnel and evacuate until no more liquid drips;

[0098] ③ Heat the remaining impregnation solution to 60°C, add the carrier that has been suctioned, and stir.

[0099] ④ Filter out the carrier and pre-dry it under vacuum at 60℃; then transfer it to a vacuum drying oven at 110℃ for activation to obtain the composite catalyst.

[0100] The Amberlyst-15 resin has a particle size of 0.7 mm and an ion exchange capacity of 4.8 mmol / g; the HPW loading rate is 30 wt%.

[0101] Amberlyst-15 resin pretreatment: Wash three times with 10 times the volume of deionized water, and vacuum dry at 60℃ for 12 hours.

[0102] The purity of phosphotungstic acid (HPW) is 99%; impregnation solution preparation: weigh HPW powder at 30% of the dry weight of the carrier, dissolve it in 200mL of deionized water, and ultrasonically disperse it for 20min at a power of 500W.

[0103] In step ①, let it stand at room temperature for 2 hours, and stir intermittently once every 30 minutes; in step ③, stir at a constant temperature of 55℃ for 2 hours; in step ④, the activation time is 2 hours.

[0104] The method for preparing MnHCF dispersion includes the following steps:

[0105] I. Prefill the reactor with deionized water, pump equal volumes of K4[Fe(CN)6] solution and manganese salt solution into the reactor, adjust the pH to 2, stir continuously, and continue the reaction for 30 minutes after the addition is complete;

[0106] II. Aging and crystallization: Heat to 60℃, stir and age for 24 hours, then centrifuge, wash with deionized water until the conductivity is 60μS / cm, and vacuum dry for 12 hours;

[0107] III. Hydrogen reduction activation: In an N2 / H2 atmosphere, the temperature is raised to 200℃, held at that temperature, and then cooled under N2 protection to obtain powder;

[0108] IV. Preparation of dispersion: The powder obtained in step III is mixed with anhydrous ethanol at a mass ratio of 1:9, magnetically stirred and then ultrasonically treated to obtain MnHCF dispersion.

[0109] The concentration of the K4[Fe(CN)6] solution is 0.1M; the raw material for the manganese salt solution is MnCl2·4H2O, with a concentration of 0.081M.

[0110] In step I, the reactor temperature is 25℃, and the pH is adjusted by adding HCl dropwise; in step III, the heating rate is 5℃ / min at a volume ratio of N2 / H2=95:5, and the holding time is 2 hours.

[0111] In step II, the heating rate is 2℃ / min, the aging process is maintained with stirring at 200rpm, and the vacuum drying temperature is 60℃; in step IV, the ultrasonic treatment power is 200W, the frequency is 40kHz, the time is 15min, and the ice bath temperature is controlled at 30℃.

[0112] The preparation method of methyl ethyl ketone peroxide includes the following steps:

[0113] (1) Add [BMIM]PF6 ionic liquid to the reactor, followed by the addition of composite catalyst, triethyl borate and methyl ethyl ketone;

[0114] (2) Cool down to 5℃, add H2O2 dropwise over 2 hours, and control the temperature at 15℃;

[0115] (3) Heat to 25°C, add MnHCF dispersion, and stir at 600 rpm for 2 hours;

[0116] (4) The reaction solution was cooled to -15℃ and crystallized for 8 hours. The solution was filtered to obtain preliminary crystals of methyl ethyl ketone peroxide. The filtrate was distilled under reduced pressure to recover the ionic liquid. The preliminary crystals of methyl ethyl ketone peroxide were dehydrated under vacuum membrane to a moisture content of 0.2%. After adding polyurethane acrylate and DPGDA, the solution was coated with gelatin-gum arabic wall material and spray-dried to obtain methyl ethyl ketone peroxide. The mass ratio of gelatin to gum arabic was 1:1.2, and the total solid content of the coating solution was 15 wt%.

[0117] The composite catalyst is an Amberlyst-15 / HPW composite support.

[0118] The molar ratio of H2O2 to methyl ethyl ketone is 1:1.1; the amount of composite catalyst added is 3 wt% of the mass of methyl ethyl ketone; the amount of triethyl borate added is 0.2 wt% of the mass of methyl ethyl ketone; the amount of MnHCF dispersion added is 0.3 wt% of the mass of methyl ethyl ketone; the amount of polyurethane acrylate added is 3.0 wt% of the mass of methyl ethyl ketone; the amount of DPGDA added is 5.0 wt% of the mass of methyl ethyl ketone; and the amount of [BMIM]PF6 ionic liquid added is 10 vol of the reactor volume.

[0119] Example 3

[0120] The preparation method of the composite catalyst includes the following steps:

[0121] ①Immerse the dried Amberlyst-15 resin in 50% HPW impregnation solution and let it stand while stirring;

[0122] ② Transfer to a Buchner funnel and evacuate until no more liquid drips;

[0123] ③ Heat the remaining impregnation solution to 60°C, add the carrier that has been suctioned, and stir.

[0124] ④ Filter out the carrier and pre-dry it under vacuum at 60℃; then transfer it to a vacuum drying oven at 110℃ for activation to obtain the composite catalyst.

[0125] The Amberlyst-15 resin has a particle size of 0.8 mm and an ion exchange capacity of 4.8 mmol / g; the HPW loading rate is 32 wt%.

[0126] Amberlyst-15 resin pretreatment: Wash three times with 10 times the volume of deionized water, and vacuum dry at 60℃ for 12 hours.

[0127] The purity of phosphotungstic acid (HPW) is 99%; impregnation solution preparation: weigh HPW powder at 30% of the dry weight of the carrier, dissolve it in 200mL of deionized water, and ultrasonically disperse it for 20min at a power of 500W.

[0128] In step ①, let it stand at room temperature for 2 hours, and stir intermittently once every 30 minutes; in step ③, stir at a constant temperature of 60℃ for 1 hour; in step ④, the activation time is 2 hours.

[0129] The method for preparing MnHCF dispersion includes the following steps:

[0130] I. Pre-fill the reactor with deionized water, pump equal volumes of K4[Fe(CN)6] solution and manganese salt solution into the reactor, adjust the pH to 2.2, stir continuously, and continue the reaction for 35 minutes after the addition is complete;

[0131] II. Aging and crystallization: Heat to 62℃, stir and age for 26 hours, then centrifuge, wash with deionized water until the conductivity is 60μS / cm, and vacuum dry for 13 hours;

[0132] III. Hydrogen reduction activation: In an N2 / H2 atmosphere, the temperature is raised to 202℃, held at that temperature, and then cooled under N2 protection to obtain powder;

[0133] IV. Preparation of dispersion: The powder obtained in step III is mixed with anhydrous ethanol at a mass ratio of 1:9, magnetically stirred and then ultrasonically treated to obtain MnHCF dispersion.

[0134] The concentration of the K4[Fe(CN)6] solution is 0.12M; the raw material for the manganese salt solution is MnCl2·4H2O, with a concentration of 0.12M.

[0135] In step I, the reactor temperature is 26℃, and the pH is adjusted by adding HCl dropwise; in step III, the heating rate is 6℃ / min at a volume ratio of N2 / H2=96:4, and the holding time is 2.2 hours.

[0136] In step II, the heating rate is 2℃ / min, the aging process is maintained with stirring at 200rpm, and the vacuum drying temperature is 62℃; in step IV, the ultrasonic treatment power is 200W, the frequency is 40kHz, the time is 20min, and the ice bath temperature is controlled at 30℃.

[0137] The preparation method of methyl ethyl ketone peroxide includes the following steps:

[0138] (1) Add [BMIM]PF6 ionic liquid to the reactor, followed by the addition of composite catalyst, triethyl borate and methyl ethyl ketone;

[0139] (2) Cool down to 9℃, add H2O2 dropwise over 2 hours, and control the temperature at 15℃;

[0140] (3) Heat to 30°C, add MnHCF dispersion, and stir at 600 rpm for 2.5 hours;

[0141] (4) The reaction solution was cooled to -10℃ and crystallized for 9 hours. The solution was filtered to obtain preliminary crystals of methyl ethyl ketone peroxide. The filtrate was distilled under reduced pressure to recover the ionic liquid. The preliminary crystals of methyl ethyl ketone peroxide were dehydrated under vacuum membrane to a moisture content of 0.2%. After adding polyurethane acrylate and DPGDA, the solution was coated with gelatin-gum arabic wall material and spray-dried to obtain methyl ethyl ketone peroxide. The mass ratio of gelatin to gum arabic was 1:1.2, and the total solid content of the coating solution was 15 wt%.

[0142] The composite catalyst is an Amberlyst-15 / HPW composite support.

[0143] The molar ratio of H2O2 to methyl ethyl ketone (MEK) is 1:1.15; the amount of composite catalyst added is 5.0 wt% of MEK mass; the amount of triethyl borate added is 0.3 wt% of MEK mass; the amount of MnHCF dispersion added is 0.4 wt% of MEK mass; the amount of polyurethane acrylate added is 4.0 wt% of MEK mass; the amount of DPGDA added is 6.0 wt% of MEK mass; and the amount of [BMIM]PF6 ionic liquid added is 12 vol of the reactor volume.

[0144] Comparative Example 1

[0145] Compared with Example 2, the difference is that MnHCF was not used, but CeO2 nanoparticles with a particle size of 30nm were used instead, with an amount of 0.5wt%. The preparation method of CeO2 nanoparticle dispersion is as follows: CeO2 nanoparticles and anhydrous ethanol are mixed at a mass ratio of 1:9, magnetic stirring is performed first, followed by ultrasonic treatment for 10-20 min, and the temperature is controlled at 25°C in an ice bath to obtain CeO2 nanoparticle dispersion.

[0146] Comparative Example 2

[0147] The difference from Example 1 is that triethyl borate was not used; instead, 0.3 wt% triphenyl phosphate was added.

[0148] Comparative Example 3

[0149] Compared with Example 3, the difference is that gelatin-gum arabic wall coating was not performed before spray drying, and the dehydrated MEKP crystals were directly spray dried to obtain uncoated MEKP powder.

[0150] Comparative Example 4

[0151] The difference from Example 2 is that [BMIM]PF6 ionic liquid was not used; instead, 12 vol% toluene was added.

[0152] Comparative Example 5

[0153] Compared with Example 2, the difference is that a mechanical mixing method was used to prepare the composite carrier. HPW and Amberlyst-15 were mechanically mixed: both were placed in a container and stirred with a mechanical stirrer at a speed of 300-500 rpm for 1-2 hours.

[0154] The test data for Examples 1-3 and Comparative Examples 1-5 are shown in Table 1.

[0155] Table 1: Test data of Examples 1-3 and Comparative Examples 1-5

[0156]

[0157] As can be seen from the data comparison in Table 1, the cyano-bridged structure of MnHCF can significantly improve catalytic efficiency. Removing MnHCF and replacing it with CeO2 will reduce AO% by 15.5%, prolong gel time by 147.8%, and increase storage decay rate by 544.4%. Microencapsulation treatment can significantly improve safety. The impact sensitivity of the unmicroencapsulated Comparative Example 3 is 4.2 J, which is about 50.6% lower than 8.5 J in Example 2, and the operational risk is significantly increased.

[0158] Application Example 1

[0159] The methyl ethyl ketone peroxide obtained in Example 2 was used in the preparation of quartz stone slabs.

[0160] Raw material weight ratio: 80 mesh quartz sand: 90 parts; UPR resin: 9 parts; MEKP: 0.5 parts.

[0161] The preparation method of quartz stone slabs is as follows: mix and stir the above raw materials at 800 rpm for 5 min, then vacuum vibrate at -0.1 MPa, 50 Hz and amplitude of 1 mm, pressurize and cure at 30 MPa and 85℃ for 20 min, and polish to obtain the slabs.

[0162] Application Example 2

[0163] The methyl ethyl ketone peroxide obtained in Example 1 was used in the preparation of calcium stone slabs.

[0164] Raw material weight ratio: 400 mesh calcium carbonate powder: 75 parts; UPR resin: 8.5 parts; MEKP: 0.6 parts.

[0165] The preparation method of calcium stone slabs is as follows: asynchronous casting with two-color slurry: time difference 1.5s, viscosity difference 600mPa·s; gelation: infrared assisted at 40℃ for 15min; demolding when the strength is 3MPa; curing at 60℃ for 2h to obtain the slabs.

[0166] Application Example 3

[0167] The methyl ethyl ketone peroxide obtained in Example 2 was used in the preparation of composite aluminum plate stone.

[0168] Raw material weight ratio: Aluminum honeycomb core: 40 parts; UPR / granite powder (mass ratio: 16:84): 58.2 parts; MEKP: 1 part.

[0169] Preparation method of composite aluminum plate stone: First, the aluminum plate is pretreated by chromic acid anodizing; then resin coating is applied with a thickness of 0.9 mm; then hot pressing is performed: 0.8 MPa, 110℃, 8 min; finally, it is cured at 23℃, 50% RH for 7 days to obtain the product.

[0170] Comparative Example 1

[0171] The difference from Application Example 1 is that methyl ethyl ketone peroxide prepared in Comparative Example 1 was used.

[0172] Comparative Example 2

[0173] The difference from Application Example 1 is that methyl ethyl ketone peroxide 239 is used.

[0174] Comparative Example 3

[0175] The difference from Application Example 2 is that methyl ethyl ketone peroxide prepared in Comparative Example 2 was used.

[0176] Comparative Example 4

[0177] The difference from Application Example 2 is that methyl ethyl ketone peroxide 239 is used.

[0178] Comparative Example 5

[0179] The difference from Application Example 3 is that methyl ethyl ketone peroxide prepared in Comparative Example 3 was used.

[0180] Comparative Example 6

[0181] The difference from Application Example 3 is that Methyl ethyl ketone peroxide M-50 is used.

[0182] The test data for Application Example 1 and Application Comparative Examples 1-2 are shown in Table 2.

[0183] The test data for Application Example 2 and Application Comparative Examples 3-4 are shown in Table 3.

[0184] The test data for Application Example 3 and Application Comparative Examples 5-6 are shown in Table 4.

[0185] Table 2: Test data for Application Example 1 and Comparative Examples 1-2

[0186]

[0187] Table 3: Test data for Application Example 2 and Comparative Examples 3-4

[0188]

[0189] Table 4: Test data for Application Example 3 and Comparative Examples 5-6

[0190]

[0191] As shown in Table 2-4, in the preparation of quartz stone slabs, the MEKP solution can improve the flexural strength by 43.7% and reduce the bubble defect rate by 96%. This is due to the high-purity MEKP-1 generated by MnHCF, which makes the solidified network more compact, as well as vacuum dehydration and low metal residue. In the preparation of calcium stone slabs, the demolding time is shortened by 32.8% and the texture clarity reaches level 5. This is because MnHCF improves the low-temperature initiation efficiency and [BMIM]PF6 can guide the molecular arrangement in a directional manner. In the preparation of composite aluminum stone panels, the accident rate is reduced by 97% and the VOC emission is reduced by 82%. This is due to the microencapsulation to avoid accidental polymerization and the replacement of phthalates with DPGDA.

Claims

1. A process for the preparation of methyl ethyl ketone peroxide, characterized in that, The method comprises the following steps: (1) adding [BMIM]PF6 ionic liquid into a reactor, and then adding a composite catalyst, triethyl borate and methyl ethyl ketone; (2) cooling to 1-10 DEG C, and adding H2O2 dropwise, the dropwise adding time being 2-2.5 hours, and the temperature being controlled to be less than or equal to 15 DEG C; (3) heating to 20-30 DEG C, and adding a MnHCF dispersion liquid, and stirring at 600 rpm for 1.5-2.5 hours; (4) cooling the reaction liquid to-20 DEG C to-10 DEG C, and crystallizing for 8-9 hours, and filtering to obtain preliminary peroxide methyl ethyl ketone crystals; the filtrate is distilled under reduced pressure to recover the ionic liquid; the preliminary peroxide methyl ethyl ketone crystals are dehydrated under vacuum to have a water content of less than or equal to 0.2 %; after adding polyurethane acrylate and dipropylene glycol diacrylate, the peroxide methyl ethyl ketone is coated by a gelatin-arabic gum wall material, and is spray dried to obtain peroxide methyl ethyl ketone; The composite catalyst is an Amberlyst-15 / phosphotungstic acid composite carrier. The preparation method of the MnHCF dispersion liquid comprises the following steps: I. pumping equal volumes of K4[Fe(CN)6] solution and manganese salt solution into a reactor, adjusting pH to be 1.8-2.2, continuously stirring, and continuing to react for 25-35 minutes after the feeding is completed; II. aging and crystallizing: heating to 58-62 DEG C, stirring for 22-26 hours, centrifugally separating, washing with deionized water until the conductivity is less than or equal to 60 muS / cm, and vacuum drying for 11-13 hours; III. hydrogen reduction activation: heating to 198-202 DEG C in an N2 / H2 atmosphere, cooling under N2 protection after heat preservation, and obtaining a powder; IV. preparing a dispersion liquid: mixing the powder and anhydrous ethanol according to a mass ratio of 1:9, magnetically stirring, and ultrasonic treating to obtain the MnHCF dispersion liquid; The raw material of the manganese salt solution is MnCl2·4H2O.

2. The method for preparing methyl ethyl ketone peroxide according to claim 1, characterized in that, The molar ratio of H2O2 to methyl ethyl ketone is 1:(1.05-1.15); the adding amount of the composite catalyst is 2.0-5.0 wt % of the mass of methyl ethyl ketone; the adding amount of triethyl borate is 0.1-0.3 wt % of the mass of methyl ethyl ketone; the adding amount of the MnHCF dispersion liquid is 0.2-0.4 wt % of the mass of methyl ethyl ketone; the adding amount of polyurethane acrylate is 2.0-4.0 wt % of the mass of methyl ethyl ketone; the adding amount of dipropylene glycol diacrylate is 4.0-6.0 wt % of the mass of methyl ethyl ketone; and the adding amount of the [BMIM]PF6 ionic liquid is 8-12 vol % of the volume of the reactor.

3. The method of claim 1, wherein the peroxide is methyl ethyl ketone peroxide. The preparation method of the composite catalyst comprises the following steps: ① immersing dry Amberlyst-15 in a 50 % phosphotungstic acid impregnation liquid, and stirring; ② transferring to a Buchner funnel, and vacuumizing until no liquid drops are dropped; ③ heating the residual impregnation liquid to 60 DEG C, and adding the sucked carrier to stir; ④ filtering out the carrier, and vacuum pre-drying at 60-62 DEG C; then transferring into a vacuum drying oven at 110-112 DEG C, and activating to obtain the composite catalyst.

4. The method of claim 3, wherein the peroxide is methyl ethyl ketone peroxide. The particle size of the Amberlyst-15 is 0.6-0.8 mm, and the ion exchange capacity is greater than or equal to 4.8 mmol / g; and the loading rate of the phosphotungstic acid is 28-32 wt %.

5. The method of claim 3, wherein the peroxide is methyl ethyl ketone peroxide. The step ① uses intermittent stirring, 30 min stirring once; the step ③ is stirred for 1-2 hours at constant temperature 55-60 ℃; the activation time in the step ④ is 2-2.5 hours.

6. The method of claim 1, wherein the peroxide is methyl ethyl ketone peroxide. The concentration of the K4[Fe(CN)6] solution is 0.08-0.12 M; the concentration of the manganese salt solution is 0.08-0.12 M.

7. The method of claim 1, wherein the peroxide is methyl ethyl ketone peroxide. In the step I, the temperature of the reactor is 24-26 ℃, and the pH is regulated by dropwise adding HCl; in the step III, the volume ratio of N2 / H2 is (94-96):(4-6), the heating rate is 4-6 ℃ / min, and the holding time is 1.8-2.2 hours.

8. A process for the preparation of methyl ethyl ketone peroxide according to claim 1, characterized in that, The prepared methyl ethyl ketone peroxide is used for artificial stone production.

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