Process for the preparation of a low-saponifiable chloroepoxy resin

Abstract

The application discloses a preparation method of a saponifiable chloro epoxy resin, and the preparation method comprises the following steps: (1) mixing alcohol, a Lewis acid and an organic solvent, stirring, and then adding epichlorohydrin to obtain a chloro alcohol ether through reaction; (2) adding liquid alkali added with a surfactant into the chloro alcohol ether in step (1) through a porous membrane to be dispersed into fine liquid drops, stirring and reacting, and then performing reduced-pressure distillation to obtain the epoxy resin. The preparation method provided by the application not only shortens the ring-closing reaction time, but also reduces the saponifiable chloro content of the product, so that the epoxy resin with the saponifiable chloro content lower than 400 ppm is obtained, and the corrosion of the saponifiable chloro of the epoxy resin on electronic equipment is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of organic synthesis, and in particular to a preparation method of low-saponification-chlorine epoxy resin. BACKGROUND

[0002] Epoxy resin has excellent mechanical properties and chemical resistance, and has a wide range of applications in various fields such as coatings, adhesives, composites and corrosion-resistant materials. Due to the excellent electrical insulation and anti-puncture performance of epoxy resin, it is more widely used in the field of electronics and electrical appliances such as insulating coating, electronic encapsulant, printed circuit board (PCB), LED packaging, capacitor impregnation and molding compound than other resins. In the microelectronic field of ultra-precision or multi-layer IC packaging, the purity and processability of epoxy resin are required to be very high. The chlorine content of general liquid epoxy resin is more than 1000 ppm, which obviously cannot meet the requirements.

[0003] Zhang Junying (Zhang Junying, Li Jianhua, Li Jingjing, et al. Preparation of high purity and low hydrolyzable chlorine content epoxy resin [J]. Petroleum Chemical Industry, 2005, 34(11): 1091-1094.) uses NaH to reduce the hydrolyzable chlorine content to meet the high purity requirements, but the steps are complicated, the operation is complex, the wastewater is large, and a large amount of low-boiling-point solvent (such as tetrahydrofuran) that is easy to produce peroxide is used, which cannot be industrialized. Xia Yu (Xia Yu, Tao Chunzhu, Rugu Xing, et al. Performance research of molecular distillation bisphenol A epoxy resin [J]. Thermosetting Resin, 2012, 27(5): 48-51) uses molecular distillation method to obtain monomolecular epoxy resin, which has very low chlorine content, solving the problem of chlorine content in epoxy resin, but not solving the problem of process.

[0004] Therefore, how to provide a simple and efficient preparation method of low-saponification-chlorine epoxy resin is a technical problem that needs to be solved in the field at present. SUMMARY

[0005] The purpose of the present application is to provide a preparation method of low-saponification-chlorine epoxy resin, which can realize simple and efficient preparation of epoxy resin with less than 400 ppm of saponification chlorine.

[0006] The present application provides the following technical solutions:

[0007] A preparation method of low-saponification-chlorine epoxy resin, the preparation method comprises:

[0008] (1) mixing alcohol, Lewis acid and organic solvent, stirring and then adding epoxy chloropropane to obtain chloroalcohol ether by reaction;

[0009] (2) adding liquid alkali with surfactant into the chloroalcohol ether of step (1) by dispersing into fine droplets through a porous membrane, stirring and closing the ring reaction, and distilling under reduced pressure to obtain epoxy resin.

[0010] The technical concept of the present application is that the addition of surfactant reduces the surface tension between the alkali solution and the oil phase, and disperses the liquid alkali into small droplets of tens to thousands of nanometers by using a porous membrane, thereby improving the contact reaction efficiency between the two-phase reactants, and reducing the saponification chlorine content of the epoxy resin.

[0011] In step (1), the alcohol is selected from one or more of the following structural formulas:

[0012]

[0013] wherein R is an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, or an aromatic group.

[0014] Preferably, the alkyl group has 1-20 carbon atoms, and is a straight chain structure, a cyclic structure, or a branched structure.

[0015] Preferably, the alkyl group has one or more substituents, and when there are multiple substituents, the substituents can be the same or different, and the positions can be the same or different.

[0016] Preferably, the aromatic group can be a benzene ring, or a naphthalene ring, or various heterocyclic compounds such as pyridine, pyrimidine, quinoline, benzothiophene, and benzothiazole; when there are multiple substituents, the substituents can be the same or different, and the positions can be the same or different.

[0017] Further preferably, the alcohol is selected from one or a combination of at least two of hydrogenated bisphenol A, 1,4-butanediol, 1,6-hexanediol, polytetrahydrofuran, trihydroxy triglycidyl ether, p-tert-butylphenol, benzyl alcohol, n-propanol, or pentaerythritol.

[0018] In step (1), the molar ratio of the alcohol to epichlorohydrin is 1:1-10; the reaction temperature is 0°C-100°C, and the reaction time is 0.5-24 hours.

[0019] In step (1), the organic solvent is selected from methanol, ethanol, isopropanol, tert-butanol, tetrahydrofuran, 2-methyltetrahydrofuran, diethyl ether, dimethyl diethyl ether, methyl tert-butyl ether, 1,4-dioxane, 1,3-dioxane, dichloromethane, 1,2-dichloroethane, chloroform, carbon tetrachloride, C 4-12 saturated alkanes, C 3-12 fluorinated or chlorinated alkanes, benzene, toluene, xylene, mesitylene, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, acetone, N-methylpyrrolidone, acetonitrile, or C 3-12At least one or a combination of at least two of the saturated alkyl nitriles.

[0020] In step (2), the surfactant is a low HLB surfactant, including but not limited to soaps or divalent metal salts of carboxylic acids, soap salts of sulfonic acids, such as one or more of sodium alkylbenzene sulfonate, fatty alcohol polyoxyethylene ether, polyoxyethylene fatty alcohol ether, etc.

[0021] The mass ratio of the liquid caustic soda to the surfactant is 1:0.001-0.1. Preferably, the mass ratio of the liquid caustic soda solution to the surfactant is 1:0.009-0.014, and the concentration of the inorganic alkali in the liquid caustic soda solution is 50%.

[0022] In step (2), the liquid alkali is an inorganic alkali, and the inorganic alkali is selected from one or a combination of at least two of sodium hydroxide, potassium hydroxide, barium hydroxide, calcium hydroxide, aluminum hydroxide, lithium hydroxide, magnesium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate or potassium bicarbonate.

[0023] In step (2), the molar ratio of the liquid alkali to the alcohol is 1:(0.1-10); the ring-closing reaction temperature is 0-100° C., and the ring-closing reaction time is 0.5-24 hours.

[0024] In step (2), the porous membrane is any one or more of an SPG membrane, an Al2O3 membrane, and a Zr2O3 membrane, and the pore size of the porous membrane ranges from 0.05 to 20 μm. Preferably, the pore size of the porous membrane ranges from 0.2 to 8 μm.

[0025] Preferably, the easily saponifiable chlorine content of the epoxy resin is less than 400 ppm. Further preferably, the easily saponifiable chlorine content of the epoxy resin is less than 300 ppm.

[0026] The present invention also provides an epoxy resin obtained according to the preparation method.

[0027] The present invention also provides an application of the epoxy resin in electronic equipment.

[0028] The present invention has the following advantages and effects:

[0029] The reaction conditions involved in the preparation method provided by the present invention have good functional group tolerance and substrate universality, and the reaction conditions are mild, simple to operate, and efficient. The product synthesized by the preparation method provided by the present invention has low easily saponifiable chlorine content and is applicable to the electronics industry with higher requirements. The preparation method provided by the present invention can simply and efficiently obtain an epoxy resin with an easily saponifiable chlorine content of less than 400 ppm. The preparation method provided by the present invention not only shortens the ring-closure reaction time, but also reduces the easily saponifiable chlorine content of the product, thereby reducing the corrosion of electronic equipment by the easily saponifiable chlorine in the epoxy resin. DETAILED DESCRIPTION

[0030] For a better understanding of the present invention, the following examples are provided to further illustrate the present invention, but the present invention is not limited to the following examples.

[0031] Example 1

[0032] Chloroform (250 g), 1,6-hexanediol (118.2 g, 1 mol), and boron trifluoride etherate (1.2 g, 0.008 mol) were added to a three-necked flask and stirred at 40°C. Epichlorohydrin (194 g, 2.1 mol) was then added dropwise using a constant pressure funnel over 30 minutes. The reaction was continued for 1.5 hours. Subsequently, at the same reaction temperature, a NaOH solution (50%, 168 g, 2.1 mol) supplemented with sodium dodecylbenzenesulfonate (2.5 g) was passed through a Zr2O3 membrane (pore size 8 μm) and added to the reaction system at a flow rate of 2 ml / min. The reaction was continued for 3 hours before termination. Finally, the reaction mixture was washed with water and then distilled under reduced pressure at 130° C. to obtain the final product with a yield of 93.3%, an epoxy value of 0.69 mol / 100 g, a viscosity of 21.4 MPa·s, and an easily saponifiable chlorine content of 371.6 ppm.

[0033] Example 2

[0034] To a three-necked flask, dichloromethane (250 g), 1,4-butanediol (90.1 g, 1 mol), and boron trifluoride etherate (1.2 g, 0.008 mol) were added and stirred at 40°C. Epichlorohydrin (194 g, 2.1 mol) was added dropwise using a constant pressure funnel over 30 minutes. After completion of the addition, the reaction was continued for 3 hours. Subsequently, a 50% NaOH solution (168 g, 2.1 mol) supplemented with sodium dodecylbenzenesulfonate (1.5 g) was added to the reaction system through an SPG membrane (5 μm pore size) at a flow rate of 2 ml / min. The reaction was continued for 3 hours before termination. The resulting reaction mixture was washed with water and then distilled under reduced pressure at 130°C to obtain the final product with a yield of 95.1%, an epoxy value of 0.79 mol / 100 g, a viscosity of 19.7 mPa·s, and easily saponifiable chlorine of 347.6 ppm.

[0035] Example 3

[0036] Add dimethyl sulfoxide (250 g), hydrogenated bisphenol A (240.4 g, 1 mol), and boron trifluoride etherate (1.2 g, 0.008 mol) into a three-necked flask and stir at 55°C. Add epichlorohydrin (194 g, 2.1 mol) using a constant pressure funnel and add dropwise for 30 minutes. After the addition is complete, continue the reaction for 2.5 hours. The temperature was then raised to 85° C., and a NaOH solution (50%, 168 g, 2.1 mol) to which sodium dodecylbenzenesulfonate (2.4 g) was added was added to the reaction system through an Al2O3 membrane (pore size, 0.2 μm) at a flow rate of 2 ml / min. The reaction was continued for 2 hours to terminate the reaction. Finally, the resulting reaction mixture was washed with water and distilled under reduced pressure at 130° C. to obtain the final product with a yield of 91.7%, an epoxy value of 0.47 mol / 100 g, a viscosity of 2786.9 MPa·s, and an easily saponifiable chlorine content of 284.0 ppm.

[0037] Comparative Example 1

[0038] Chloroform (250 g), 1,6-hexanediol (118.2 g, 1 mol), and boron trifluoride etherate (1.2 g, 0.008 mol) were added to a three-necked flask and stirred at 40°C. Epichlorohydrin (194 g, 2.1 mol) was then added dropwise using a constant pressure funnel over 30 minutes. The reaction was continued for 1.5 hours. Subsequently, NaOH solution (50%, 168 g, 2.1 mol) and tetrabutylammonium bromide (1.2 g) were added at the same reaction temperature and allowed to react for 3 hours before terminating the reaction. The resulting reaction mixture was washed with water and then distilled under reduced pressure at 130°C to obtain the final product with a yield of 83.9%, an epoxy value of 0.67 mol / 100 g, a viscosity of 19.2 MPa·s, and easily saponifiable chlorine of 1971.6 ppm.

[0039] Comparative Example 2

[0040] Dichloromethane (250 g), 1,4-butanediol (90.1 g, 1 mol), and boron trifluoride etherate (1.2 g, 0.008 mol) were added to a three-necked flask and stirred at 40°C. Epichlorohydrin (194 g, 2.1 mol) was then added dropwise using a constant pressure funnel over 30 minutes. After completion, the reaction was continued for 3 hours. Subsequently, NaOH solution (50%, 168 g, 2.1 mol) and tetrabutylammonium chloride (1.2 g) were added dropwise at the same reaction temperature. The reaction was continued for another 3 hours before termination. The resulting reaction mixture was washed with water and then distilled under reduced pressure at 130°C to obtain the final product with a yield of 90.1%, an epoxy value of 0.78 mol / 100 g, a viscosity of 17.7 MPa·s, and easily saponifiable chlorine of 1267.5 ppm.

[0041] Comparative Example 3

[0042] To a three-necked flask was added dimethyl sulfoxide (250 g), hydrogenated bisphenol A (240.4 g, 1 mol), boron trifluoride etherate (1.2 g, 0.008 mol) and stirred at 55°C. Epoxy chloropropane (194 g, 2.1 mol) was added dropwise through a constant pressure funnel over 30 min. After the addition was completed, the reaction was continued for 2.5 hours. Then the temperature was raised to 85°C and a solution of sodium dodecylbenzenesulfonate (2.4 g) in NaOH (50%, 160 g, 2 mol) was added to the reaction system through an Al2O3 membrane (pore size 50 um) at a flow rate of 2 ml / min. The reaction was continued for 2 hours to complete the reaction. Finally, the obtained reaction mixture was washed with water and distilled under reduced pressure at 130°C to obtain the final product. The yield was 91.1%, the epoxy value was 0.47 mol / 100 g, the viscosity was 2272.1 mpa.s and the easy saponification chlorine was 644.7 ppm.

[0043] The product properties of Examples 1-3 and Comparative Examples 1-3 are shown in Table 1. As can be seen from Table 1, dispersing the alkali solution through the porous membrane is essentially beneficial to the ring closure reaction, and the ring closure reaction is more complete, which has a more obvious effect on reducing the easy saponification chlorine. The smaller the pore size of the porous membrane, the more beneficial to the dispersion of liquid alkali, and the more beneficial to the reaction.

[0044] Table 1: Product properties of Examples 1-3 and Comparative Examples 1-3

[0045]

[0046] The above is only a preferred embodiment of the present application, of course, cannot be limited to the scope of the present application, should be noted that, for those skilled in the art, without departing from the principles of the present application, can make a number of improvements and changes, these improvements and changes are also considered to be within the scope of the present application.

Claims

1. A method for preparing a low-saponifiable chlorine epoxy resin, characterized in that: The preparation method comprises: (1) Mixing alcohol, Lewis acid and organic solvent, stirring and adding epichlorohydrin to react to obtain chlorohydrin ether; (2) Liquid alkali with added surfactant is dispersed into fine droplets through a porous membrane and added to the chlorohydrin ether of step (1) for stirring and reaction, and then distilled under reduced pressure to obtain epoxy resin.

2. The method for preparing a low-saponifiable chlorine epoxy resin according to claim 1, wherein: In step (1), the alcohol is selected from one or more of the following structural formulas: 、 、 、 ； Wherein, R is an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group or an aromatic group.

3. The method for preparing a low-saponifiable chlorine epoxy resin according to claim 1 or 2, wherein: The alcohol is selected from one or a combination of at least two of hydrogenated bisphenol A, 1,4-butanediol, 1,6-hexanediol, polytetrahydrofuran, trihydroxy triglycidyl ether, p-tert-butylphenol, benzyl alcohol, n-propanol or pentaerythritol.

4. The method for preparing a low-saponifiable chlorine epoxy resin according to claim 1, wherein: In step (1), the molar ratio of the alcohol to epichlorohydrin is 1:1-10; the reaction temperature is 0°C-100°C; and the reaction time is 0.5-24 hours.

5. The method for preparing a low-saponifiable chlorine epoxy resin according to claim 1, wherein: In step (1), the organic solvent is selected from tetrahydrofuran, 2-methyltetrahydrofuran, ether, dimethyl ethyl diether, methyl tert-butyl ether, 1,4-epoxyhexadecane, 1,3-epoxyhexadecane, dichloromethane, 1,2-dichloroethane, chloroform, carbon tetrachloride, C 4-12 Saturated alkanes, C 3-12 Fluorinated or chlorinated alkanes, benzene, toluene, xylene, trimethylbenzene, dimethyl sulfoxide, N , N -dimethylformamide, N , N -Dimethylacetamide, acetone, N -methylpyrrolidone, acetonitrile or C 3-12 One or a combination of at least two of the saturated alkyl nitriles.

6. The method for preparing a low-saponifiable chlorine epoxy resin according to claim 1, wherein: In step (2), the surfactant is selected from one or a combination of at least two of polyoxyethylene fatty alcohol ether, fatty alcohol polyoxyethylene ether, sodium alkyl sulfonate or sodium alkylbenzene sulfonate; and the mass ratio of the liquid caustic soda to the surfactant is 1:0.001~0.

1.

7. The method for preparing a low-saponifiable chlorine epoxy resin according to claim 1, wherein: In step (2), the liquid alkali is selected from one or a combination of at least two of sodium hydroxide, potassium hydroxide, barium hydroxide, calcium hydroxide, aluminum hydroxide, lithium hydroxide, magnesium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate or potassium bicarbonate.

8. The method for preparing a low-saponifiable chlorine epoxy resin according to any one of claims 1 or 6-7, characterized in that: The molar ratio of the liquid alkali to the alcohol is 1:0.1-10; the ring-closing reaction temperature is 0-100° C.; and the ring-closing reaction time is 0.5-24 hours.

9. The method for preparing a low-saponifiable chlorine epoxy resin according to claim 1, wherein: In step (2), the porous membrane is selected from one or a combination of at least two of an SPG membrane, an Al2O3 membrane, and a Zr2O3 membrane; the pore size of the porous membrane ranges from 0.05 to 20 μm.

10. The method for preparing a low-saponifiable chlorine epoxy resin according to claim 1, wherein: The easily saponifiable chlorine content of the epoxy resin is less than 400 ppm.

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