Dicumyl peroxide and its preparation method and application

Abstract

The present invention relates to the technical field of cumene hydroperoxide production, specifically to cumene hydroperoxide and its preparation method and application. Cumene is mixed with a composite stabilizer, hydrogen peroxide and TiO 2 -PW catalyst are added, and the reaction is carried out at 65 °C for 1.5 hours under nitrogen protection; then the temperature is raised to 85 °C and the reaction is carried out for 4 hours; the obtained reaction solution is cooled to 40 °C, and the catalyst is recovered by filtration; the aqueous phase is removed by liquid separation, and the organic phase is washed with 5% sodium bicarbonate solution until neutral; then the unreacted cumene is removed by vacuum distillation, and then treated by molecular sieve adsorption decolorization and ethanol recrystallization, and cumene hydroperoxide is obtained after drying. By using a composite stabilizer, the present invention effectively inhibits the decomposition of hydrogen peroxide, improves the stability of the reaction system, reduces the occurrence of side reactions, and improves the production efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of dicumyl peroxide production, in particular to dicumyl peroxide and a preparation method and application thereof. Background Art

[0002] As an important organic peroxide, dicumyl peroxide (DCP) plays an irreplaceable role in many industrial fields. In the rubber vulcanization process, it can promote the cross-linking reaction of rubber molecular chains, improve the strength, elasticity and wear resistance of rubber, and is widely used in the production of rubber products such as tires and seals; in terms of plastic cross-linking, DCP can transform the molecular structure of plastics from linear to three-dimensional network, thereby improving the heat resistance, chemical stability and mechanical properties of plastics, and is widely used in the production of plastic products such as pipes and plates.

[0003] However, the current preparation technology of DCP has many drawbacks. From the perspective of catalysts, concentrated sulfuric acid is often used as a catalyst in traditional processes. Although concentrated sulfuric acid can promote the reaction to a certain extent, it is highly corrosive and causes great damage to production equipment. The annual corrosion rate of equipment exceeds 0.1mm, which not only increases the cost of equipment maintenance and replacement, but also poses a safety hazard; at the same time, the reaction will produce a large amount of waste acid that is difficult to handle, which is costly to handle and does not meet the current strict environmental protection requirements. In terms of catalytic effect, the activity and selectivity of existing catalytic systems are poor, resulting in frequent side reactions during the reaction, such as the sulfonation reaction of isopropylbenzene, which makes the product purity generally low, usually less than 98%, and the yield is also not ideal, generally less than 85%. Moreover, the content of by-products (such as isopropylphenol) in the product is relatively high, exceeding 5%, which undoubtedly increases the difficulty and cost of subsequent product purification. In addition, there are also problems with the stability and safety of the reaction system. During the reaction, hydrogen peroxide (H 2 O 2 ) have poor stability and are easily decomposed. The decomposition rate exceeds 15%, which not only reduces the utilization rate of raw materials but also may cause the reaction to run away. The metal ions in the system (such as Fe 3+ , Cu 2+ ) will catalyze H 2 O 2 The homolytic cleavage generates hydroxyl radicals (·OH), which further aggravates the occurrence of side reactions and affects product quality and production safety.

[0004] The demand for thermosetting inks continues to grow in industries such as electronic circuits and packaging printing. In the field of electronic circuits, when used for printing electronic components such as printed circuit boards, extremely high requirements are placed on the performance of the ink, such as conductivity, adhesion, and abrasion resistance; in the packaging printing industry, the ink is required to have good color expressiveness, weather resistance, and compatibility with different packaging materials. However, there are obvious technical bottlenecks in existing thermosetting inks. In terms of performance, the functions of traditional thermosetting inks are relatively single. Their conductivity is extremely poor, with a surface resistance as high as 10 15 Ω / sq, far from meeting the application scenarios with strict requirements for conductivity such as electronic packaging; when increasing the resin content to improve the abrasion resistance of the ink, the curing shrinkage rate will increase significantly, exceeding 3%, which causes the adhesion of the coating on the printing substrate to decrease. Through the cross-cut test, the adhesion grade is ≥1 level, affecting the printing quality and the service life of the product. In terms of dispersibility and stability, the components such as pigments and fillers in traditional inks are not evenly dispersed, and agglomeration and sedimentation are likely to occur during storage and use, resulting in uneven colors and decreased pattern clarity during printing; moreover, the single thermosetting method in the existing process requires treatment at high temperature (140 - 150°C) for a long time (>5 minutes), which not only has high energy consumption but is also not suitable for heat-sensitive substrates, limiting the application range of thermosetting inks. Summary of the Invention

[0005] In view of the above deficiencies in the prior art, the object of the present invention is to provide a diisopropylbenzene peroxide. By using a composite stabilizer, the decomposition of hydrogen peroxide is effectively inhibited, and the decomposition rate is reduced from 15% to 2.5%, significantly improving the stability of the reaction system, reducing the occurrence of side reactions, and greatly reducing the content of by-products.

[0006] Another object of the present invention is to provide a preparation method of diisopropylbenzene peroxide. By controlling the reaction temperature and time, as well as molecular sieve adsorption decolorization and ethanol recrystallization treatment, the yield of DCP is increased, the content of by-products is reduced, and the product is made purer.

[0007] The third object of the present invention is to provide an application of diisopropylbenzene peroxide. The prepared thermosetting ink has good comprehensive performance. The surface resistance is as low as 1.2×10 6 Ω / sq, with excellent conductivity, meeting the printing requirements for ink conductivity in electronic circuits and other fields.

[0008] The present invention is realized by adopting the following technical solutions:

[0009] The preparation method of the diisopropylbenzene peroxide described includes the following steps:

[0010] (1) Mix cumene with a composite stabilizer and dehydrate under reduced pressure at 60°C until the water content ≤ 30 ppm;

[0011] (2) Add hydrogen peroxide and TiO 2 -PW catalyst, and react at 65 °C for 1.5 hours under nitrogen protection; then raise the temperature to 85 °C and react for 4 hours, and add TiO 2 -PW catalyst during this period to obtain a reaction solution;

[0012] (3) Cool the reaction solution obtained in step (2) to 40 °C, filter to recover the catalyst; separate the aqueous phase by liquid separation, and wash the organic phase with a sodium bicarbonate solution with a concentration of 4-6% until neutral; then remove the unreacted cumene by vacuum distillation, and then perform molecular sieve adsorption decolorization and ethanol recrystallization treatment, and dry to obtain diisopropylbenzene peroxide;

[0013] The composite stabilizer is obtained by mixing disodium ethylenediaminetetraacetate (EDTA-2Na) and sodium pyrophosphate (TSPP) in a mass ratio of 1:1;

[0014] The TiO 2 -PW catalyst is a composite catalyst composed of titanium dioxide and phosphotungstic acid.

[0015] Molecular sieve adsorption decolorization includes the following steps:

[0016] Molecular sieve pretreatment: 3A molecular sieve (pore size 0.3 nm, used to adsorb small molecule pigments and moisture).

[0017] Activation conditions: Temperature: 300 °C; Time: 4 hours; Atmosphere: Nitrogen protection.

[0018] Adsorption decolorization: Molecular sieve dosage: 5% of the mass of the crude product; Temperature: 40 ± 2 °C; Time: 2 hours (mechanical stirring, rotation speed 100 rpm); Endpoint control: Solution transmittance ≥ 95% (detected by UV-Vis, wavelength 450 nm).

[0019] Filtration and separation: Filtration equipment: Plate and frame filter press (filter cloth pore size 1 μm); Washing: Rinse the filter cake with a 10% ethanol solution (volume ratio 1:1).

[0020] 3A molecular sieve selectively adsorbs small molecule pigments (such as cumene oxidation products) and simultaneously removes trace moisture (to avoid abnormal growth of crystal nuclei during recrystallization). Compared with traditional activated carbon, the molecular sieve does not adsorb DCP, and the product loss rate < 0.5%.

[0021] Ethanol recrystallization includes the following steps:

[0022] Dissolution solvent ratio of the crude product: Crude DCP: Ethanol = 1:4 (mass ratio); Temperature: 60 °C (reflux dissolution, time 30 minutes).

[0023] Gradient cooling crystallization: Cooling procedure: 60°C → 40°C (rate 1°C / min); 40°C → 25°C (rate 0.5°C / min); Standing at 25°C: 4 hours.

[0024] Filtration and drying: Suction filtration with a Buchner funnel (vacuum degree -0.08 MPa); Washing twice with cold ethanol (0 - 5°C) (each time the dosage is 1 time the volume of the crystals); Drying: Temperature: 35°C (vacuum drying oven); Time: 12 hours; Finished product index: Purity ≥ 99.8% (HPLC), melting point 39.0 - 39.3°C (measured by DSC).

[0025] Gradient cooling controls the crystal growth rate to avoid encapsulating impurities, and cold ethanol washing removes surface residual low-melting by-products (such as diisopropyl ether).

[0026] The molar ratio of cumene to hydrogen peroxide is 1:(1.05 - 1.15), and the addition amount of TiO 2 -PW catalyst is 0.3 - 1.0% of the mass of cumene, and the addition amount of the composite stabilizer is 0.2 - 0.4% of the mass of cumene; In step (2), the additional TiO 2 -PW catalyst accounts for 0.1% of the total mass of the added TiO 2 -PW catalyst.

[0027] The purity of the dicumyl peroxide described is ≥ 99.8%, and the melting point is 38.5 - 39.5°C.

[0028] The preparation method of the TiO 2 -PW catalyst includes the following steps:

[0029] a. Calcining the nano-TiO 2 at 300°C for 2 hours;

[0030] b. Immersing the nano-TiO 2 treated in step a in a 0.5 mol / L phosphotungstic acid aqueous solution, and ultrasonically dispersing for 1 hour to obtain a mixed solution;

[0031] c. Evaporating the mixed solution obtained in step b to dryness at 80°C, drying at 120°C, and then calcining at 500°C for 3 hours to obtain the TiO 2 -PW catalyst.

[0032] The particle size of the nano-TiO 2 described is 20 nm, the specific surface area ≥ 150 m² / g, and the loading amount of the TiO 2 -PW catalyst is 10 - 15 wt%.

[0033] In the preparation process of DCP, the composite stabilizer plays a key role. Disodium ethylenediaminetetraacetate can chelate metal ions (such as Fe 3+ ) in the reaction system, making the residual Fe 3+ ≤0.1 ppm, effectively inhibiting the decomposition reaction of H 2 O 2 catalyzed by metal ions; Sodium pyrophosphate adjusts the pH value of the reaction solution to 5.5 - 6.0, avoiding the sulfonation side reaction of cumene under acidic conditions, thereby reducing the generation of by-products. The action mechanism of the TiO 2 -PW catalyst is that the nano-TiO 2 provides a large specific surface area, enabling phosphotungstic acid to be highly dispersed and stably loaded, and the Ti - O - W bonding structure endows the catalyst with unique catalytic active sites. At 65 °C, the reaction starts smoothly, which is beneficial to the activation of hydrogen peroxide; when the temperature is raised to 85 °C, the reaction rate increases, promoting the condensation reaction. Controlling the temperature in stages enables the reaction to proceed efficiently and orderly. In the purification stage after the reaction, due to its specific pore size (0.3 nm), 3A molecular sieve can selectively adsorb small molecule pigments and moisture, while avoiding the adsorption of DCP, reducing product loss; during the ethanol gradient recrystallization process, by controlling the cooling rate (the rate from 60 °C to 40 °C is 1 °C / min, and the rate from 40 °C to 25 °C is 0.5 °C / min), the DCP crystals grow slowly and evenly, effectively avoiding the entrapment of impurities, thereby improving the purity of the product.

[0034] The described dicumyl peroxide is prepared by the above preparation method of dicumyl peroxide.

[0035] The application of the described dicumyl peroxide is used for preparing thermosetting ink.

[0036] The preparation method of the described thermosetting ink includes the following steps:

[0037] Ⅰ. Mix epoxy acrylate resin, hyperbranched polyester acrylate, trimethylolpropane triacrylate, dicumyl peroxide, graphene nanosheets, pigments and additives at 60 °C with a planetary mixer for 30 minutes to form a homogeneous system, obtaining a premix.

[0038] Ⅱ. Premix graphene and trimethylolpropane triacrylate at a mass ratio of 1:10 and ball mill for 2 hours at 400 rpm to form a graphene dispersion; add the graphene dispersion to the premix and shear at high speed at 2000 rpm for 1 hour until the fineness ≤ 20 μm.

[0039] Ⅲ. Then grind it 3 times with a tungsten carbide three-roll mill to make the fineness ≤ 5 μm; then filter it through a 500-mesh filter under nitrogen pressure, and control the finished product viscosity to 2800 - 3200 cps to obtain the thermosetting ink.

[0040] The pigment described is phthalocyanine blue BGS, and the additives include leveling agent BYK-333, defoaming agent TegoFoamex 810, nano-silica, and benzophenone; the roll gap pressure of the tungsten carbide three-roll mill is 0.2 - 0.3 MPa; the trimethylolpropane triacrylate used in Step I is 70 - 80% of its total dosage; the trimethylolpropane triacrylate used in Step II is 20 - 30% of its total dosage.

[0041] The mass percentages of each raw material are as follows: epoxy acrylate resin (EA): 35 - 45%; hyperbranched polyester acrylate (HBPEA): 10 - 15%; trimethylolpropane triacrylate (TMPTA): 12 - 18%; dicumyl peroxide: 3 - 5%; graphene nanosheets: 0.1 - 0.5%; phthalocyanine blue BGS: 10 - 12%; nano-silica: 8 - 12%; benzophenone: 1 - 2%; leveling agent BYK-333: 0.5 - 1%; defoaming agent TegoFoamex 810: 0.3 - 0.8%; graphene: 1.2 - 1.8%.

[0042] In the preparation process of the thermosetting ink, the raw materials cooperate with each other to achieve a synergistic improvement in performance. Graphene nanosheets have excellent electrical conductivity and mechanical properties. After ball milling and dispersion, their ultrathin lamellae are evenly distributed in the ink system, and interface bonding occurs with the free radicals generated by the decomposition of DCP, not only constructing a conductive path but also enhancing the wear resistance of the ink. The three-dimensional structure of hyperbranched polyester acrylate (HBPEA) plays a role in reducing the viscosity in the system, facilitating the uniform dispersion of each component; its multiple acrylate groups can undergo cross-linking reactions with the free radicals generated by the decomposition of DCP to form a dense three-dimensional cross-linked network, thereby reducing the curing shrinkage rate and improving the adhesion and hardness of the ink. Benzophenone (BP) as a photoinitiator can rapidly generate free radicals under UV irradiation to initiate the pre-curing reaction, enabling the ink to be preliminarily cured in a short time; during the subsequent heating process at 130 °C, DCP further decomposes to generate free radicals, promoting the full cross-linking of the resin and acrylate monomers to achieve deep curing, making up for the deficiencies of UV curing and enhancing the overall curing effect and performance of the ink. Epoxy acrylate resin and hyperbranched polyester acrylate, as the main film-forming substances, provide the basic properties of the ink. Trimethylolpropane triacrylate participates in the cross-linking reaction to enhance the hardness and wear resistance of the ink. Diisopropylbenzene peroxide decomposes to generate free radicals under heating conditions, initiating the cross-linking reaction of the resin and acrylate monomers to form a three-dimensional network structure, causing the ink to cure into a film. Pigment phthalocyanine blue BGS imparts color to the ink, and nano-silica can adjust the rheological properties of the ink and promote the cross-linking reaction during heating. The leveling agent BYK-333 and the defoaming agent TegoFoamex 810 respectively improve the leveling property of the ink and eliminate bubbles. The raw materials cooperate with each other to jointly enhance the comprehensive performance of the thermosetting ink.

[0043] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0044] (1) By adopting a composite stabilizer (disodium ethylenediaminetetraacetate and sodium pyrophosphate mixed in a mass ratio of 1:1), the decomposition of hydrogen peroxide is effectively inhibited, reducing the decomposition rate from 15% to 2.5%, significantly improving the stability of the reaction system, reducing the occurrence of side reactions, greatly reducing the content of by-products, and using TiO 2 -PW catalyst, with the Ti-O-W bonding structure formed by loading phosphotungstic acid (PW) on the nano-TiO 2 support (specific surface area ≥ 150 m² / g), has unique Lewis acid sites (Ti 4+ ) and redox active sites (W=O bond), greatly enhancing the catalytic efficiency. The reaction conditions of staged temperature control (65 °C → 85 °C) precisely match H 2 O 2The activation and condensation reaction kinetics enabled the DCP yield to reach 95.1%, far higher than 82.3% of traditional sulfuric acid catalysis. Moreover, this catalyst could be recycled more than 10 times, and its activity could still remain above 95% after recycling. In the purification process, molecular sieve adsorption decolorization (3A molecular sieve) was adopted to selectively remove small-molecule pigments, avoiding product loss caused by traditional activated carbon adsorption, and the product loss rate was less than 0.5%. The ethanol gradient recrystallization (60°C → 25°C) process could accurately control crystal growth, and finally the purity of the obtained DCP was increased to above 99.8% (detected by HPLC), effectively improving the product quality.

[0045] (2) Graphene nanosheets (0.1 - 0.5%) were ball-milled and dispersed to form ultrathin lamellae (≤5 nm), which underwent interfacial bonding (C - O - C) with DCP free radicals, successfully constructing a conductive path, reducing the surface resistance of the ink to as low as 10 6 Ω / sq, and simultaneously significantly improving the wear resistance. After Taber testing, the weight loss was only 8 mg / 1000 times. Hyperbranched polyester acrylate (HBPEA) reduced the system viscosity due to its three-dimensional structure. Its high functionality (6 - 8 acrylate groups) and DCP synergistically formed a dense cross-linked network, reducing the curing shrinkage rate to 1.2%, which was significantly lower than that of traditional inks, effectively improving the comprehensive performance of the ink. The application of the photo-thermal dual-curing system also had great advantages. Benzophenone (BP) initiated pre-curing under UV irradiation (500 mJ / cm²), significantly reducing the thermal curing time from 8 minutes of traditional single thermal curing to 3 minutes. DCP underwent deep cross-linking at 130°C, making up for the problem of insufficient UV curing penetration, enabling the hardness of the ink to reach 2H (ASTM D3363) and the adhesion to reach grade 0 (no peeling), greatly improving the curing effect of the ink and the coating quality. Detailed implementation manners

[0046] In order to make the objectives and technical solutions of the present invention clearer and more understandable, the present invention will be further described in detail below.

[0047] The sources of some raw materials for the following examples, comparative examples, application examples, and application comparative examples are as follows:

[0048] Disodium ethylenediaminetetraacetate (EDTA - 2Na): Nantong Aokai Biotechnology Development Co., Ltd.;

[0049] Sodium pyrophosphate (TSPP): Shanghai Yiji Industrial Co., Ltd.;

[0050] Nano-titanium dioxide (TiO 2 ) : Shanghai Huijing Asian Nano New Materials Co., Ltd.;

[0051] Epoxy acrylate resin: Changxing Chemical Industry Co., Ltd.;

[0052] Hyperbranched polyester acrylate: DSM Group;

[0053] Trimethylolpropane triacrylate: BASF Corporation;

[0054] Graphene nanosheets: Nanjing Xianfeng Nano Material Technology Co., Ltd.;

[0055] Phthalocyanine blue BGS: BASF Corporation;

[0056] Nano silica: Cabot Corporation;

[0057] Benzophenone: Shandong Jinling Chemical Co., Ltd.;

[0058] Leveling agent BYK–333: BYK Chemie GmbH;

[0059] Defoaming agent TegoFoamex810: Evonik Industries AG.

[0060] Test method:

[0061] DCP yield: According to the chemical reaction equation, the mass of diisopropylbenzene peroxide theoretically generated is calculated based on the feeding amount of cumene in the reaction. After the reaction is completed, the diisopropylbenzene peroxide product obtained is separated and dried, and its mass is accurately weighed. The yield = (actual product mass ÷ theoretical product mass) × 100%.

[0062] DCP purity (HPLC): GB / T22313-2008 "Plastics - Determination of the purity of toluene diisocyanate for use in the production of polyurethanes".

[0063] Content of DCP by-products (GC): GB / T30921.2-2016 "Test methods for industrial purified terephthalic acid (PTA) - Part 2: Determination of the contents of 4-carboxybenzaldehyde (4-CBA) and p-toluic acid (p-TOL)".

[0064] Catalyst recycling times and activity: After each reaction is completed, the catalyst is filtered and recovered, washed with an appropriate solvent (such as ethanol) and dried. The recovered catalyst is used for the preparation reaction of diisopropylbenzene peroxide under the same conditions, and repeated multiple times (10 times). The yield of the product is measured after each reaction. Based on the yield of the first reaction, the retention rate of the yield of subsequent reactions is calculated to evaluate the recycling activity of the catalyst.

[0065] Surface resistance of the ink: GB / T2439-2001 "Rubber, vulcanized or thermoplastic - Determination of electrical resistivity for conductive and dissipative properties".

[0066] Ink adhesion (cross-cut method): GB / T 9286-1998 "Cross-Cut Test for Coatings of Paints and Varnishes".

[0067] Ink abrasion resistance: Tested using a Taber abrasion tester in accordance with relevant industry standards (ASTM D4060 "Standard Test Method for Abrasion Resistance of Organic Coatings by the Taber Abraser").

[0068] Ink curing shrinkage rate: GB / T 1682-2014 "Determination of Low Temperature Brittleness of Vulcanized Rubber - Single Specimen Method".

[0069] Ink curing time: Place the test plate coated with ink in an oven at 130°C. Take out the test plate at regular intervals (1 minute), and use a hardness test pen or other suitable tool to check the curing degree of the ink. Record the time (in minutes) required for the ink to be completely cured.

[0070] Ink resistance to ethanol wiping: Dip a cotton ball in anhydrous ethanol, apply a certain pressure (500 g / cm²) on the surface of the cured ink film, and wipe back and forth at a constant speed (30 times per minute). Record the number of wiping times when obvious color fading (color becoming lighter, scratches appearing) occurs on the ink film.

[0071] In the following examples and comparative examples, the specific treatment conditions for molecular sieve adsorption decolorization and ethanol recrystallization are as follows:

[0072] Molecular sieve adsorption decolorization includes the following steps:

[0073] Molecular sieve pretreatment: 3A molecular sieve (pore size 0.3 nm, used for adsorbing small molecule pigments and moisture).

[0074] Activation conditions: Temperature: 300°C; Time: 4 hours; Atmosphere: Nitrogen protection.

[0075] Adsorption decolorization: Molecular sieve dosage: 5% of the mass of the crude product; Temperature: 40°C; Time: 2 hours (mechanical stirring, rotation speed 100 rpm); Endpoint control: Solution transmittance is 95% (detected by UV-Vis, wavelength 450 nm).

[0076] Filtration and separation: Filtration equipment: Plate and frame filter press (filter cloth pore size 1 μm); Washing: Rinse the filter cake with 10% ethanol solution (volume ratio 1:1).

[0077] 3A molecular sieve selectively adsorbs small molecule pigments and simultaneously removes trace moisture. Compared with traditional activated carbon, the molecular sieve does not adsorb DCP, and the product loss rate is 0.3%.

[0078] Ethanol recrystallization includes the following steps:

[0079] Ratio of solvents for dissolving the crude product: Crude DCP: Ethanol = 1:4 (mass ratio); Temperature: 60 °C (dissolved under reflux for 30 minutes).

[0080] Gradient cooling crystallization: Cooling program: 60 °C → 40 °C (rate 1 °C / min); 40 °C → 25 °C (rate 0.5 °C / min); Standing at 25 °C: 4 hours.

[0081] Filtration and drying: Filtration with a Buchner funnel (vacuum degree -0.08 MPa); Washing twice with cold ethanol (0 - 5 °C) (each time the dosage is 1 times the volume of the crystals); Drying: Temperature: 35 °C (in a vacuum drying oven); Time: 12 hours.

[0082] Example 1

[0083] TiO 2 Preparation method of -PW catalyst, comprising the following steps:

[0084] a. Calcinate the nano-TiO 2 at 300 °C for 2 hours;

[0085] b. Immerse the nano-TiO 2 treated in step a in an aqueous solution of 0.5 mol / L phosphotungstic acid, and ultrasonically disperse for 1 hour to obtain a mixed solution;

[0086] c. Evaporate the mixed solution obtained in step b to dryness at 80 °C, dry at 120 °C, and then calcine at 500 °C for 3 hours to obtain TiO 2 -PW catalyst.

[0087] The particle size of the nano-TiO 2 is 20 nm, the specific surface area is 150 m² / g, and the loading amount of the TiO 2 -PW catalyst is 12 wt%.

[0088] Preparation method of dicumyl peroxide, comprising the following steps:

[0089] (1) Mix cumene with a composite stabilizer, and dehydrate under reduced pressure at 60 °C until the water content is 30 ppm;

[0090] (2) Add hydrogen peroxide and TiO 2 -PW catalyst, react at 65 °C for 1.5 hours under nitrogen protection; then raise the temperature to 85 °C and react for 4 hours, and add TiO 2 -PW catalyst during the period to obtain a reaction solution;

[0091] (3) Cool the reaction solution obtained in step (2) to 40 °C, filter to recover the catalyst; separate and remove the aqueous phase, wash the organic phase with a 5% sodium bicarbonate solution until neutral; then remove the unreacted cumene by vacuum distillation, and then perform molecular sieve adsorption decolorization and ethanol recrystallization treatment. After drying, obtain diisopropylbenzene peroxide;

[0092] The composite stabilizer is obtained by mixing disodium ethylenediaminetetraacetate and sodium pyrophosphate in a mass ratio of 1:1.

[0093] Among them, the molar ratio of cumene to hydrogen peroxide is 1:1.1, and the addition amount of TiO 2 -PW catalyst is 0.6% of the mass of cumene, and the addition amount of the composite stabilizer is 0.3% of the mass of cumene; in step (2), the additional TiO 2 -PW catalyst accounts for 0.1% of the total mass of the added TiO 2 -PW catalyst.

[0094] Example 2

[0095] TiO 2 The preparation method of -PW catalyst includes the following steps:

[0096] a. Calcinate the nano-TiO 2 at 300 °C for 2 hours;

[0097] b. Immerse the nano-TiO 2 treated in step a in a 0.5 mol / L phosphotungstic acid aqueous solution, and ultrasonically disperse for 1 hour to obtain a mixed solution;

[0098] c. Evaporate the mixed solution obtained in step b to dryness at 80 °C, dry at 120 °C, and then calcine at 500 °C for 3 hours to obtain TiO 2 -PW catalyst.

[0099] The particle size of nano-TiO 2 is 20 nm, the specific surface area is 150 m² / g, and the loading amount of TiO 2 -PW catalyst is 15 wt%.

[0100] The preparation method of diisopropylbenzene peroxide includes the following steps:

[0101] (1) Mix cumene with the composite stabilizer, and dehydrate under reduced pressure at 60 °C until the water content is 30 ppm;

[0102] (2) Add hydrogen peroxide and TiO 2 -PW catalyst, react at 65 °C for 1.5 hours under nitrogen protection; then raise the temperature to 85 °C and react for 4 hours, and add TiO 2 -PW catalyst during the period to obtain a reaction solution;

[0103] (3) Cool the reaction solution obtained in step (2) to 40 °C, filter to recover the catalyst; separate and remove the aqueous phase, wash the organic phase with a 4% sodium bicarbonate solution until neutral; then remove the unreacted cumene by vacuum distillation, and then perform molecular sieve adsorption decolorization and ethanol recrystallization treatment. After drying, cumene hydroperoxide is obtained;

[0104] The composite stabilizer is obtained by mixing disodium ethylenediaminetetraacetate and sodium pyrophosphate in a mass ratio of 1:1.

[0105] Among them, the molar ratio of cumene to hydrogen peroxide is 1:1.15, and the addition amount of TiO 2 -PW catalyst is 1.0% of the mass of cumene, and the addition amount of the composite stabilizer is 0.4% of the mass of cumene; in step (2), the additional TiO 2 -PW catalyst accounts for 0.1% of the total mass of the added TiO 2 -PW catalyst.

[0106] Example 3

[0107] Preparation method of TiO 2 -PW catalyst, including the following steps:

[0108] a. Calcinate the nano-TiO 2 at 300 °C for 2 hours;

[0109] b. Immerse the nano-TiO 2 treated in step a in a 0.5 mol / L phosphotungstic acid aqueous solution, and ultrasonically disperse for 1 hour to obtain a mixed solution;

[0110] c. Evaporate the mixed solution obtained in step b to dryness at 80 °C, dry at 120 °C, and then calcine at 500 °C for 3 hours to obtain TiO 2 -PW catalyst.

[0111] The particle size of nano-TiO 2 is 20 nm, the specific surface area is 150 m² / g, and the loading amount of TiO 2 -PW catalyst is 10 wt%.

[0112] Preparation method of cumene hydroperoxide, including the following steps:

[0113] (1) Mix cumene with the composite stabilizer, and dehydrate under reduced pressure at 60 °C until the water content is 30 ppm;

[0114] (2) Add hydrogen peroxide and TiO 2 -PW catalyst, react at 65 °C for 1.5 hours under nitrogen protection; then raise the temperature to 85 °C and react for 4 hours, and add additional TiO during this period2 -PW catalyst to obtain a reaction solution;

[0115] (3) Cool the reaction solution obtained in step (2) to 40 °C, filter to recover the catalyst; separate and remove the aqueous phase, wash the organic phase with a 6% sodium bicarbonate solution until neutral; then remove the unreacted cumene by vacuum distillation, and then perform molecular sieve adsorption decolorization and ethanol recrystallization treatment. After drying, obtain dicumyl peroxide;

[0116] The composite stabilizer is obtained by mixing disodium ethylenediaminetetraacetate and sodium pyrophosphate in a mass ratio of 1:1.

[0117] Among them, the molar ratio of cumene to hydrogen peroxide is 1:1.05, TiO 2 The addition amount of -PW catalyst is 0.3% of the mass of cumene, and the addition amount of the composite stabilizer is 0.2% of the mass of cumene; in step (2), the additional TiO 2 -PW catalyst accounts for 0.1% of the total mass of TiO 2 -PW catalyst added.

[0118] Comparative Example 1

[0119] The difference from Example 1 is that the stabilizer is EDTA-2Na.

[0120] Comparative Example 2

[0121] The difference from Example 2 is that the catalyst is changed to concentrated sulfuric acid.

[0122] Comparative Example 3

[0123] The difference from Example 3 is that the molecular sieve used is HZSM-5 molecular sieve.

[0124] Comparative Example 4

[0125] The difference from Example 1 is that no stabilizer is added.

[0126] Comparative Example 5

[0127] The difference from Example 1 is that the reaction temperature is 85 °C and the reaction is for 6 hours.

[0128] Comparative Example 6

[0129] The difference from Example 1 is that molecular sieve decolorization is not used. The prepared dicumyl peroxide is yellowish in color (small molecule pigments are not selectively adsorbed), and the residual trace moisture > 30 ppm, which affects the recrystallization process (abnormal growth of crystal nuclei) and reduces the crystal uniformity.

[0130] The test data of Examples 1-3 and Comparative Examples 1-6 are shown in Table 1.

[0131] Table 1: Test Data of Examples 1-3 and Comparative Examples 1-6

[0132]

[0133] Through the analysis of Table 1, it can be seen that: by chelating metal ions (Fe 3+ ≤0.1 ppm), side reactions are reduced (by-product content ≤ 1.5%); nano-TiO 2 (specific surface area ≥ 150 m² / g) is loaded with phosphotungstic acid to form a Ti-O-W bonding structure, which has both Lewis acid sites (Ti 4+ ) and redox active sites (W=O), with high catalytic efficiency (yield reaching 95.1%), and can be recycled more than 10 times (activity retention ≥ 90%). By controlling the temperature (65 °C → 85 °C), it matches the activation and condensation kinetics of H 2 O 2 and improves the reaction efficiency.

[0134] Application Example 1

[0135] A preparation method of thermosetting ink, comprising the following steps:

[0136] Ⅰ. Mix epoxy acrylate resin, hyperbranched polyester acrylate, trimethylolpropane triacrylate, dicumyl peroxide obtained in Example 1, graphene nanosheets, pigments and additives at 60 °C with a planetary mixer for 30 minutes to form a homogeneous system, obtaining a premix;

[0137] Ⅱ. Premix graphene and trimethylolpropane triacrylate at a mass ratio of 1:10 and ball mill for 2 hours at 400 rpm to form a graphene dispersion; add the graphene dispersion to the premix and shear at high speed at 2000 rpm for 1 hour until the fineness reaches 20 μm;

[0138] Ⅲ. Then grind it 3 times with a tungsten carbide three-roll mill to make the fineness 5 μm; then filter it through a 500-mesh filter under nitrogen pressure, and control the finished product viscosity to 3000 cps to obtain thermosetting ink.

[0139] The pigment is phthalocyanine blue BGS, and the additives include a leveling agent BYK-333, an antifoaming agent TegoFoamex810, nano-silica and benzophenone; the roll gap pressure of the tungsten carbide three-roll mill is 0.3 MPa; the trimethylolpropane triacrylate used in step Ⅰ is 75% of its total amount; the trimethylolpropane triacrylate used in step Ⅱ is 25% of its total amount.

[0140] The mass percentages of each raw material are as follows: epoxy acrylate resin: 42%; hyperbranched polyester acrylate: 13%; trimethylolpropane triacrylate: 15%; dicumyl peroxide: 4%; graphene nanosheets: 0.3%; phthalocyanine blue BGS: 11%; nano-silica: 10%; benzophenone: 1.5%; leveling agent BYK-333: 1%; defoaming agent TegoFoamex810: 0.7%; graphene: 1.5%.

[0141] Application Example 2

[0142] A preparation method of a thermosetting ink, comprising the following steps:

[0143] Ⅰ. Mix epoxy acrylate resin, hyperbranched polyester acrylate, trimethylolpropane triacrylate, the dicumyl peroxide obtained in Example 1, graphene nanosheets, pigments and additives at 60 °C with a planetary mixer for 30 minutes to form a homogeneous system, obtaining a premix;

[0144] Ⅱ. Premix graphene and trimethylolpropane triacrylate according to a mass ratio of 1:10, and ball mill at 400 rpm for 2 hours to form a graphene dispersion; add the graphene dispersion to the premix and shear at a high speed of 2000 rpm for 1 hour until the fineness reaches 20 μm;

[0145] Ⅲ. Then grind with a tungsten carbide three-roll mill for 3 times to make the fineness reach 5 μm; then filter through a 500-mesh filter screen under nitrogen pressure, and control the finished product viscosity to 2800 cps to obtain the thermosetting ink.

[0146] The pigment is phthalocyanine blue BGS, and the additives include leveling agent BYK-333, defoaming agent TegoFoamex810, nano-silica and benzophenone; the roll gap pressure of the tungsten carbide three-roll mill is 0.2 MPa; the trimethylolpropane triacrylate used in Step Ⅰ is 70% of its total dosage; the trimethylolpropane triacrylate used in Step Ⅱ is 30% of its total dosage.

[0147] The mass percentages of each raw material are as follows: epoxy acrylate resin: 45%; hyperbranched polyester acrylate: 10%; trimethylolpropane triacrylate: 14%; dicumyl peroxide: 5%; graphene nanosheets: 0.5%; phthalocyanine blue BGS: 12%; nano-silica: 8.6%; benzophenone: 2%; leveling agent BYK-333: 0.7%; defoaming agent TegoFoamex810: 0.8%; graphene: 1.4%.

[0148] Application Example 3

[0149] A preparation method of a thermosetting ink, comprising the following steps:

[0150] Ⅰ. Mix epoxy acrylate, hyperbranched polyester acrylate, trimethylolpropane triacrylate, dicumyl peroxide obtained in Example 2, graphene nanosheets, pigments and additives at 60 °C with a planetary mixer for 30 minutes to form a homogeneous system and obtain a premix;

[0151] Ⅱ. Premix graphene and trimethylolpropane triacrylate at a mass ratio of 1:10 and ball mill for 2 hours at 400 rpm to form a graphene dispersion; add the graphene dispersion to the premix and shear at high speed at 2000 rpm for 1 hour until the fineness reaches 20 μm;

[0152] Ⅲ. Then grind 3 times with a tungsten carbide three-roll mill to make the fineness reach 5 μm; then filter through a 500-mesh filter under nitrogen pressure, and control the finished product viscosity to 3200 cps to obtain a thermosetting ink.

[0153] The pigment is phthalocyanine blue BGS, and the additives include a leveling agent BYK-333, an antifoaming agent TegoFoamex810, nano-silica and benzophenone; the roll gap pressure of the tungsten carbide three-roll mill is 0.2 - 0.3 MPa; the trimethylolpropane triacrylate used in Step Ⅰ is 80% of its total amount; the trimethylolpropane triacrylate used in Step Ⅱ is 20% of its total amount.

[0154] The mass percentages of each raw material are as follows: epoxy acrylate: 35%; hyperbranched polyester acrylate: 13.2%; trimethylolpropane triacrylate: 18%; dicumyl peroxide: 5%; graphene nanosheets: 0.2%; phthalocyanine blue BGS: 11%; nano-silica: 12%; benzophenone: 2%; leveling agent BYK-333: 1%; antifoaming agent TegoFoamex810: 0.8%; graphene: 1.8%.

[0155] Application Comparative Example 1

[0156] The difference from Application Example 1 is that graphene is not added;

[0157] Application Comparative Example 2

[0158] The difference from Application Example 2 is that HBPEA is not added.

[0159] Application Comparative Example 3

[0160] The difference from Application Example 3 is that DCP is replaced with benzoyl peroxide (BPO).

[0161] Application Comparative Example 4

[0162] The difference from Application Example 1 is that BP is not added (only thermosetting).

[0163] Application Comparative Example 5

[0164] The difference from Application Example 1 is that the DCP prepared in Comparative Example 1 is used.

[0165] In the performance test of the thermosetting ink, it is necessary to perform a standardized coating operation on the inks obtained from the application examples and application comparative examples. The specific steps are as follows:

[0166] Substrate pretreatment: Select a printed circuit board (PCB) as the substrate, wipe the surface with anhydrous ethanol to remove grease and dust, and dry it for later use.

[0167] Ink coating: Pour the ink into a coater, and use a wire bar coater (wire diameter 25 μm) to coat it on the surface of the substrate, controlling the wet film thickness to be 20 μm. After coating, let it stand for 5 minutes (room temperature 25 °C) to allow the ink to level.

[0168] Curing treatment: UV pre-curing: Use a UV curing machine (wavelength 365 nm, light intensity 500 mJ / cm²), irradiate for 3 minutes to preliminarily crosslink the ink.

[0169] Thermosetting: Place the pre-cured sample in an oven at 130 °C and heat for 3 minutes to complete deep curing.

[0170] Test sample preparation: The cured ink film needs to be placed in a constant temperature and humidity environment (25 °C, humidity 50%) for 24 hours. After ensuring stable performance, carry out subsequent tests.

[0171] The test data of Application Examples 1-3 and Application Comparative Examples 1-5 are shown in Table 2.

[0172] Table 2: Test data of Application Examples 1-3 and Application Comparative Examples 1-5

[0173]

[0174] Through the analysis of Table 2, it can be seen that: in terms of conductivity, graphene nanosheets (0.1-0.5%) build a conductive path, and the surface resistance is as low as 1.2×10 6 Ω / sq. In terms of wear resistance and adhesion, hyperbranched polyester acrylate (HBPEA) and DCP crosslink synergistically, the curing shrinkage rate is reduced to 1.2% (traditional 3.5%), and the adhesion reaches grade 0 (no peeling). UV pre-curing (3 minutes) combined with DCP thermosetting (130 °C) shortens the total curing time to 3 minutes, and the hardness reaches 2H.

Claims

1. A method for preparing dicumyl peroxide, characterized in that: The following steps are involved: (1) Mix cumene and composite stabilizer and dehydrate under reduced pressure at 60°C until the water content is ≤30ppm; (2) adding hydrogen peroxide and TiO2-PW catalyst, reacting at 65°C for 1.5 hours under nitrogen protection; then raising the temperature to 85°C for 4 hours, during which TiO2-PW catalyst was added to obtain a reaction solution; (3) The reaction solution obtained in step (2) is cooled to 40° C., and the catalyst is recovered by filtration; the aqueous phase is separated and the organic phase is washed with a 4-6% sodium bicarbonate solution until it is neutral; unreacted cumene is removed by vacuum distillation, and then decolorized by molecular sieve adsorption and recrystallized with ethanol, and dried to obtain dicumyl peroxide; The composite stabilizer is obtained by mixing disodium ethylenediaminetetraacetate and sodium pyrophosphate in a mass ratio of 1:1; The TiO2-PW catalyst is a composite catalyst composed of titanium dioxide and phosphotungstic acid; The molecular sieve is 3A molecular sieve with a pore size of 0.3 nm.

2. The method for preparing dicumyl peroxide according to claim 1, characterized in that: The molar ratio of cumene to hydrogen peroxide is 1:(1.05-1.15), the amount of TiO2-PW catalyst added is 0.3-1.0% of the mass of cumene, and the amount of composite stabilizer added is 0.2-0.4% of the mass of cumene; in step (2), the added TiO2-PW catalyst accounts for 0.1% of the total mass of the TiO2-PW catalyst added.

3. The method for preparing dicumyl peroxide according to claim 1, characterized in that: The purity of the dicumyl peroxide is ≥99.8%, and the melting point is 38.5-39.5°C.

4. The method for preparing dicumyl peroxide according to claim 1, characterized in that: The preparation method of the TiO2-PW catalyst comprises the following steps: a. Calcine nano-TiO2 at 300°C for 2 hours; b. The nano-TiO2 treated in step a was immersed in a 0.5 mol / L aqueous phosphotungstic acid solution and ultrasonically dispersed for 1 hour to obtain a mixed solution; c. The mixed solution obtained in step b was evaporated to dryness at 80 ℃, dried at 120 ℃, and calcined at 500 ℃ for 3 hours to obtain a TiO2-PW catalyst.

5. The method for preparing dicumyl peroxide according to claim 4, characterized in that: The particle size of the nano-TiO2 is 20nm, the specific surface area is ≥150m² / g, and the loading amount of the TiO2-PW catalyst is 10-15wt%.

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