Preparation method of water-borne epoxy resin binder and application of water-borne epoxy resin binder in printing ink

Abstract

The invention relates to the technical field of printing ink, and discloses a preparation method of a water-borne epoxy resin binder and application of the water-borne epoxy resin binder in printing ink, water and nano titanium dioxide are added into a container, modified silicone oil is added after ultrasonic treatment, stirring and dispersing are carried out, then water-borne epoxy resin, a defoaming agent, a flatting agent and a thickening agent are added, stirring and uniform mixing are carried out, and the water-borne epoxy resin binder is obtained. The waterborne epoxy resin binder is obtained. The catechol structure of the modified silicone oil can be coordinated with the surface of the nano titanium dioxide, so that the surface coating modification of the nano titanium dioxide is realized, the agglomeration of the nano titanium dioxide is reduced, the dispersity of the nano titanium dioxide in a water-borne epoxy resin connecting material is improved, and the emulsion is free of precipitation and layering and very good in storage stability. The imino group contained in the modified silicone oil can be subjected to a curing reaction with the epoxy resin, so that a very good toughening effect is achieved, and meanwhile, the heat resistance and flame retardance of the epoxy resin are improved.

Description

Technical Field

[0001] The invention relates to the technical field of inks, and in particular to a method for preparing a water-based epoxy resin binder and application of the same in inks. Background Art

[0002] Epoxy resin is widely used in ink binders, coatings, adhesives and other fields due to its good waterproof, anti-corrosion and insulation properties. Toughening modification of epoxy resin is a research hotspot. Adding carboxyl-terminated nitrile rubber, amino silicone oil, amino-terminated polyurethane, etc. to epoxy resin can improve the toughness and strength of epoxy resin, making it have better practical applications in high-performance ink binders and other aspects.

[0003] Silicone oil is a high molecular polymer containing a polysiloxane structure, which has good toughness, high heat resistance and excellent flame retardancy; Patent CN117143479B discloses a solder mask ink suitable for automotive circuit boards and its preparation method. The ink obtained by using epoxy resin, glycidyl methacrylate, hydrogen-containing silicone oil, unsaturated dicarboxylic acid, and hydrosilylation catalyst as raw materials has good thermal shock resistance. However, the patent does not solve the problem of poor toughness, heat resistance and flame retardancy of epoxy resin.

[0004] Nano-titanium dioxide is cheap, readily available, green and pollution-free, has high mechanical strength and high heat resistance, and is widely used in materials such as inks, coatings, and plastics. Improving the agglomeration problem of nano-titanium dioxide and improving its compatibility with polymer resins are research difficulties. Summary of the invention

[0005] The technical problem solved by the invention is to provide an aqueous epoxy resin connecting material for ink with high mechanical properties and heat resistance.

[0006] The technical solution of the present invention is: a method for preparing a water-based epoxy resin connecting material:

[0007] (1) Add toluene, hydrogenated silicone oil and allyl intermediate into a reaction vessel, add isopropanol solution of chloroplatinic acid in a nitrogen atmosphere, heat to 80-90°C, react for 3-5h, rotary evaporate and dry to obtain modified silicone oil.

[0008] (2) Add water and nano-titanium dioxide into a container, add modified silicone oil after ultrasonic treatment, heat to 40-60°C, stir and disperse for 3-6 hours, then add water-based epoxy resin, defoamer, leveling agent, thickener, stir and mix to obtain a water-based epoxy resin binder.

[0009] Preferably, the molar ratio of Si-H bonds in the hydrogenated silicone oil to the allyl intermediate in (1) is 1:(0.8-1); the mass of chloroplatinic acid is 0.015-0.022% of the mass of the allyl intermediate.

[0010] Preferably, the mass of nano-titanium dioxide and modified silicone oil in (2) is 0.5-4% and 5-20% of the mass of the water-based epoxy resin, respectively.

[0011] Preferably, the preparation method of the allyl intermediate is:

[0012] A1. Add ethanol and water in a volume ratio of 1:(0.6-0.8) and 3,4-dihydroxybenzaldehyde and 3-amino-1,2,4-triazole in a molar ratio of 1:(1-1.1) into a reaction vessel, heat to 60-80°C, react for 1-2h, remove tetrahydrofuran by rotary evaporation, extract with ethyl acetate, dry the organic phase to remove water, and purify by recrystallization to obtain a triazole intermediate.

[0013] A2. Add triazole intermediate, 3-bromopropylene, and catalyst 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in a molar ratio of 1:(1-1.2):(1-1.4) to tetrahydrofuran, react at room temperature for 8-12 hours, rotary evaporate, wash with petroleum ether, add the product to ethanol, add sodium borohydride, stir and react for 3-5 hours, add water, extract with ethyl acetate, dry the organic phase to remove water, and purify by recrystallization to obtain an allyl intermediate. The reaction formula is:

[0014]

[0015] Preferably, water-based epoxy resin binder is used in ink.

[0016] Beneficial effects: The present invention utilizes the alkenyl group of the allyl intermediate to react with the Si-H bond of the hydrogen-containing silicone oil to obtain a modified silicone oil containing a hydrophilic imino group, a catechol structure and a triazole structure, which significantly improves the hydrophilicity of the modified silicone oil, making the modified silicone oil compatible with the water-based epoxy resin binder, and the emulsion is not easy to stratify. In addition, the catechol structure of the modified silicone oil can coordinate with the surface of nano-titanium dioxide, thereby achieving surface coating modification of the nano-titanium dioxide, which is beneficial to reducing the agglomeration of the nano-titanium dioxide and improving its dispersibility in the water-based epoxy resin binder. The emulsion has no precipitation, no stratification, and good storage stability.

[0017] The modified silicone oil of the present invention contains an imino group which can undergo a curing reaction with the epoxy resin, thereby bonding the flexible polysiloxane of the silicone oil to the epoxy resin molecular chain, thereby enhancing the bonding strength between the silicone oil and the epoxy resin and playing a good toughening role. Meanwhile, the evenly dispersed nano titanium dioxide plays a good reinforcing role, which is beneficial to improving the tensile strength and elongation at break of the epoxy resin.

[0018] The modified silicone oil of the present invention forms a stable cured cross-linking network in the epoxy resin, which is beneficial to improving the heat resistance of the epoxy resin and increasing the thermal decomposition temperature. The polysiloxane structure and the triazole structure in the modified silicone oil form a nitrogen silicon flame retardant, which generates inorganic silicon substances and non-flammable gases such as nitrogen when burned, and combines with nano titanium dioxide to achieve better flame retardant properties and improve the limiting oxygen index. DETAILED DESCRIPTION

[0019] In order to further understand the present invention, the preferred embodiments of the present invention are described below in conjunction with examples, but it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than for limiting the claims of the invention. Those skilled in the art can refer to the contents of this article and appropriately improve the process parameters to achieve. The raw materials, reactions and post-processing means appearing in the examples, unless otherwise stated, are common raw materials on the market, and technical means well known to those skilled in the art.

[0020] The defoamer of the present invention is model YL-218, Nantong Yongle Chemical. The leveling agent is model BYK-345, Green Union (Jining) Chemical Technology. The water-based epoxy resin is model MR1487W, Guangdong Keding Functional Materials. The hydrogen-containing silicone oil, with a hydrogen content of 1.58%, is from Zhejiang Woxingman New Material Technology.

[0021] Example 1

[0022] (1) Add 100 mL of ethanol, 60 mL of water, 40 mmol of 3,4-dihydroxybenzaldehyde, and 44 mmol of 3-amino-1,2,4-triazole in a volume ratio to a reaction container, heat to 80° C., react for 1 hour, remove tetrahydrofuran by rotary evaporation, extract with ethyl acetate, dry the organic phase to remove water, and purify by recrystallization to obtain a triazole intermediate.

[0023] (2) Add 30 mmol of triazole intermediate, 36 mmol of 3-bromopropylene and 42 mmol of 1,8-diazabicyclo[5.4.0]undec-7-ene to 80 mL of tetrahydrofuran, react at room temperature for 8 h, rotary evaporate, wash with petroleum ether, add the product to 100 mL of ethanol, add 36 mmol of sodium borohydride, stir and react for 5 h, add water, extract with ethyl acetate, dry the organic phase to remove water, and purify by recrystallization to obtain the allyl intermediate.

[0024] (3) Add 50 mL of toluene, 50 g of hydrogenated silicone oil and an allyl intermediate into a reaction vessel, and control the molar ratio of Si-H bonds in the hydrogenated silicone oil to the allyl intermediate to be 1:1; add 2 mL of an isopropanol solution of chloroplatinic acid in a nitrogen atmosphere, wherein the mass of chloroplatinic acid is 0.018% of the mass of the allyl intermediate; heat to 85° C., react for 5 h, rotary evaporate, and dry to obtain modified silicone oil.

[0025] (4) Add 240 mL of water and 1 g of nano-titanium dioxide (average particle size 40 nm) into the container, add 10 g of modified silicone oil after ultrasonic treatment for 10 min, heat to 40 ° C, stir and disperse for 4 h, then add 200 g of water-based epoxy resin, 1.4 g of defoamer, 1.6 g of leveling agent, and 1.5 g of thickener sodium carboxymethyl cellulose, stir and mix to obtain a water-based epoxy resin binder.

[0026] Example 2

[0027] (1) Add 100 mL of ethanol, 60 mL of water, 40 mmol of 3,4-dihydroxybenzaldehyde, and 40 mmol of 3-amino-1,2,4-triazole in a volume ratio to a reaction container, heat to 60° C., react for 2 h, remove tetrahydrofuran by rotary evaporation, extract with ethyl acetate, dry the organic phase to remove water, and purify by recrystallization to obtain a triazole intermediate.

[0028] (2) Add 30 mmol of triazole intermediate, 30 mmol of 3-bromopropylene and 30 mmol of 1,8-diazabicyclo[5.4.0]undec-7-ene to 60 mL of tetrahydrofuran, react at room temperature for 12 h, rotary evaporate, wash with petroleum ether, add the product to 120 mL of ethanol, add 39 mmol of sodium borohydride, stir and react for 3 h, add water, extract with ethyl acetate, dry the organic phase to remove water, and purify by recrystallization to obtain the allyl intermediate.

[0029] (3) Add 60 mL of toluene, 50 g of hydrogenated silicone oil and an allyl intermediate into a reaction vessel, and control the molar ratio of Si-H bonds in the hydrogenated silicone oil to the allyl intermediate to be 1:1; add 2 mL of an isopropanol solution of chloroplatinic acid in a nitrogen atmosphere, wherein the mass of chloroplatinic acid is 0.022% of the mass of the allyl intermediate; heat to 80° C., react for 5 h, rotary evaporate, and dry to obtain modified silicone oil.

[0030] (4) Add 260 mL of water and 4 g of nano titanium dioxide (average particle size 40 nm) into the container, add 10 g of modified silicone oil after ultrasonic treatment for 10 min, heat to 60 ° C, stir and disperse for 3 h, then add 200 g of water-based epoxy resin, 2 g of defoamer, 1.6 g of leveling agent, and 1 g of thickener sodium carboxymethyl cellulose, stir and mix to obtain a water-based epoxy resin binder.

[0031] Example 3

[0032] (1) Add 50 mL of toluene, 50 g of hydrogenated silicone oil, and an allyl intermediate (prepared in Example 1) into a reaction container, and control the molar ratio of Si-H bonds in the hydrogenated silicone oil to the allyl intermediate to be 1:0.8; add 2 mL of an isopropanol solution of chloroplatinic acid in a nitrogen atmosphere, wherein the mass of chloroplatinic acid is 0.015% of the mass of the allyl intermediate; heat to 90° C., react for 3 h, rotary evaporate, and dry to obtain a modified silicone oil.

[0033] (2) Add 260 mL of water and 8 g of nano titanium dioxide (average particle size 40 nm) into a container, add 10 g of modified silicone oil after ultrasonic treatment for 10 min, heat to 50 ° C, stir and disperse for 6 h, then add 200 g of water-based epoxy resin, 1.5 g of defoamer, 1.2 g of leveling agent, and 1.8 g of thickener sodium carboxymethyl cellulose, stir and mix to obtain a water-based epoxy resin binder.

[0034] Example 4

[0035] (1) Add 60 mL of toluene, 50 g of hydrogenated silicone oil, and an allyl intermediate (prepared in Example 1) into a reaction container, and control the molar ratio of Si-H bonds in the hydrogenated silicone oil to the allyl intermediate to be 1:1; add 2 mL of an isopropanol solution of chloroplatinic acid in a nitrogen atmosphere, wherein the mass of chloroplatinic acid is 0.02% of the mass of the allyl intermediate; heat to 90° C., react for 4 h, rotary evaporate, and dry to obtain a modified silicone oil.

[0036] (2) Add 260 mL of water and 4 g of nano titanium dioxide (average particle size 40 nm) into a container, add 25 g of modified silicone oil after ultrasonic treatment for 10 min, heat to 50 ° C, stir and disperse for 3 h, then add 200 g of water-based epoxy resin, 2 g of defoamer, 1.6 g of leveling agent, and 1 g of thickener sodium carboxymethyl cellulose, stir and mix to obtain a water-based epoxy resin binder.

[0037] Example 5

[0038] (1) Add 50 mL of toluene, 50 g of hydrogenated silicone oil, and an allyl intermediate (prepared in Example 1) into a reaction container, and control the molar ratio of Si-H bonds in the hydrogenated silicone oil to the allyl intermediate to be 1:0.8; add 2 mL of an isopropanol solution of chloroplatinic acid in a nitrogen atmosphere, wherein the mass of chloroplatinic acid is 0.02% of the mass of the allyl intermediate; heat to 80° C., react for 5 h, rotary evaporate, and dry to obtain a modified silicone oil.

[0039] (2) Add 260 mL of water and 4 g of nano titanium dioxide (average particle size 40 nm) into a container, add 40 g of modified silicone oil after ultrasonic treatment for 10 min, heat to 50 ° C, stir and disperse for 6 h, then add 200 g of water-based epoxy resin, 2 g of defoamer, 1.6 g of leveling agent, and 1 g of thickener sodium carboxymethyl cellulose, stir and mix to obtain a water-based epoxy resin binder.

[0040] Comparative Example 1

[0041] (1) Add 240 mL of water and 1 g of nano titanium dioxide (average particle size 40 nm) into a container, and then add 200 g of water-based epoxy resin, 1.4 g of defoamer, 1.6 g of leveling agent, and 1.5 g of thickener sodium carboxymethyl cellulose after ultrasonic treatment for 10 minutes, and stir to mix well to obtain a water-based epoxy resin binder.

[0042] Comparative Example 2

[0043] (1) Add 240 mL of water and 1 g of nano titanium dioxide (average particle size 40 nm) into a container, add 10 g of hydrogenated silicone oil after ultrasonic treatment for 10 min, heat to 40 ° C, stir and disperse for 4 h, then add 200 g of water-based epoxy resin, 1.4 g of defoamer, 1.6 g of leveling agent, and 1.5 g of thickener sodium carboxymethyl cellulose, stir and mix to obtain a water-based epoxy resin binder.

[0044] Comparative Example 3

[0045] (1) Add 10 g of modified silicone oil (prepared in Example 1), 200 g of water-based epoxy resin, 1.4 g of defoamer, 1.6 g of leveling agent, and 1.5 g of thickener sodium carboxymethyl cellulose into a container, stir and mix to obtain a water-based epoxy resin binder.

[0046] The waterborne epoxy resin binder was stored at 25°C for 1-6 months and the stability of the emulsion was observed.

[0047] Table 1

[0048]

[0049] Add 11.3 g of diethylenetriamine curing agent to the water-based epoxy resin binder, stir to mix, apply it on the tinplate surface, and bake at 120°C for 1 h and 150°C for 20 min respectively; test the adhesion according to the method of GB / T13217.7-2023.

[0050] Add 11.8g of diethylenetriamine curing agent to the waterborne epoxy resin binder, stir and mix, pour into the mold, cure at 100℃ for 2h and 120℃ for 4h to make a casting sample. Test the tensile properties according to the method of GB / T 2567-2021.

[0051] Weigh 5 mg of the casting sample and perform thermogravimetric analysis in a thermogravimetric analyzer in a nitrogen atmosphere with a heating rate of 10°C / min and a maximum test temperature of 800°C.

[0052] The limiting oxygen index of the casting sample was tested according to the method of GB / T 2406.1-2008.

[0053] Table 2

[0054]

[0055] Table 3

[0056]

[0057] As shown in Tables 1-3, nano titanium dioxide is added to the epoxy resin binder of Comparative Example 1. Since nano titanium dioxide is easy to agglomerate, has poor compatibility with epoxy resin, and has poor dispersibility, the storage stability of the epoxy resin binder emulsion is poor. When stored for a long time, titanium dioxide precipitation is easily generated, and the adhesion grade, tensile strength and elongation at break of the cured product are low, and the mechanical properties are poor. At the same time, the initial thermal decomposition temperature, mass residual rate and limiting oxygen index are low, and the heat resistance and flame retardancy are poor.

[0058] Comparative Example 2 added nano titanium dioxide and hydrogen-containing silicone oil. Since the hydrogen-containing silicone oil is hydrophobic, it is incompatible in the water-based epoxy resin binder emulsion. After storage, the emulsion is easily stratified and titanium dioxide precipitation is produced. The storage stability is poor. In addition, the hydrogen-containing silicone oil cannot undergo a curing reaction with the epoxy resin and has poor compatibility with the epoxy resin. After curing, the adhesion grade, tensile strength and elongation at break of the epoxy resin are low, and the mechanical properties are poor. At the same time, the initial thermal decomposition temperature, mass residual rate and limiting oxygen index are low, and the heat resistance and flame retardancy are poor.

[0059] Nano titanium dioxide and modified silicone oil are added to the waterborne epoxy resin binder of embodiment 1-5, and the modified silicone oil contains hydrophilic imino group, catechol structure and triazole structure, which significantly improves the hydrophilicity of the modified silicone oil, so that the modified silicone oil is compatible with the waterborne epoxy resin binder, and the emulsion is not easy to stratify. In addition, during the stirring and dispersing process, the catechol structure of the modified silicone oil can coordinate with the surface of the nano titanium dioxide, and the surface coating modification of the nano titanium dioxide is realized, which is conducive to reducing the agglomeration of the nano titanium dioxide and improving its dispersibility in the waterborne epoxy resin binder. The emulsion has no precipitation, no stratification, and good storage stability. In addition, the imino group contained in the modified silicone oil can undergo a curing reaction with the epoxy resin, thereby bonding the flexible polysiloxane of the silicone oil to the epoxy resin molecular chain, enhancing the bonding strength of the silicone oil and the epoxy resin, and playing a good toughening effect. At the same time, the uniformly dispersed nano titanium dioxide plays a good reinforcing effect, which is conducive to improving the tensile strength and elongation at break of the epoxy resin. Modified silicone oil forms a stable cured cross-linking network in epoxy resin, which is beneficial to improve the thermal properties of epoxy resin and increase the thermal decomposition temperature. The polysiloxane structure and triazole structure in the modified silicone oil form a nitrogen silicon flame retardant, which produces inorganic silicon substances and non-flammable gases such as nitrogen when burned. Combined with nano-titanium dioxide, it has better flame retardant properties and a larger limiting oxygen index.

[0060] Compared with Example 1, in Comparative Example 3, modified silicone oil is added, and the epoxy resin binder emulsion has no stratification, no precipitation, and good storage stability. However, nano titanium dioxide is not added, and the tensile strength and elongation at break of the epoxy resin are lower, and the initial thermal decomposition temperature, mass loss rate and limiting oxygen index are slightly lower than those of Example 1.

Claims

1. A method for preparing a waterborne epoxy resin binder, characterized in that: The preparation method of the waterborne epoxy resin binder is: (1) Add toluene, hydrogenated silicone oil and the structural formula The allyl intermediate is added with an isopropanol solution of chloroplatinic acid in a nitrogen atmosphere, heated to 80-90°C, reacted for 3-5h, rotary evaporated, and dried to obtain a modified silicone oil; (2) Add water and nano-titanium dioxide into a container, add modified silicone oil after ultrasonic treatment, stir and disperse, then add water-based epoxy resin, defoamer, leveling agent, thickener, stir and mix to obtain a water-based epoxy resin binder.

2. The method for preparing the waterborne epoxy resin binder according to claim 1, characterized in that: The molar ratio of Si-H bonds in the hydrogenated silicone oil to the allyl intermediate in (1) is 1:(0.8-1); the mass of chloroplatinic acid is 0.015-0.022% of the mass of the allyl intermediate.

3. The method for preparing a waterborne epoxy resin binder according to claim 1, characterized in that: The mass of the nano titanium dioxide and the modified silicone oil in (2) is 0.5-4% and 5-20% of the mass of the waterborne epoxy resin respectively.

4. The method for preparing the waterborne epoxy resin binder according to claim 1, characterized in that: The temperature during the stirring and dispersing in (2) is 40-60° C. and the time is 3-6 hours.

5. The method for preparing the waterborne epoxy resin binder according to claim 1, characterized in that: The preparation method of the allyl intermediate is: A1. Add ethanol, water, 3,4-dihydroxybenzaldehyde and 3-amino-1,2,4-triazole to a reaction vessel, heat to 60-80°C, react for 1-2h, rotary evaporate, extract with ethyl acetate, dry the organic phase to remove water, and purify by recrystallization to obtain a triazole intermediate; A2. Add triazole intermediate, 3-bromopropylene and 1,8-diazabicyclo[5.4.0]undec-7-ene to tetrahydrofuran, react at room temperature for 8-12 hours, rotary evaporate, wash, add the product to ethanol, add sodium borohydride, stir and react for 3-5 hours, add water, extract with ethyl acetate, dry the organic phase to remove water, purify by recrystallization, and obtain the allyl intermediate.

6. The method for preparing the waterborne epoxy resin binder according to claim 5, characterized in that: The molar ratio of 3,4-dihydroxybenzaldehyde to 3-amino-1,2,4-triazole in A1 is 1:(1-1.1).

7. The method for preparing the waterborne epoxy resin binder according to claim 5, characterized in that: The volume ratio of ethanol to water in A1 is 1:(0.6-0.8).

8. The method for preparing the waterborne epoxy resin binder according to claim 5, characterized in that: The molar ratio of the triazole intermediate, 3-bromopropylene and 1,8-diazabicyclo[5.4.0]undec-7-ene in A2 is 1:(1-1.2):(1-1.4).

9. Use of a water-based epoxy resin binder obtained by the preparation method according to any one of claims 1 to 8 in ink.

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