Preparation method of low-temperature curing resin

Abstract

The invention belongs to the technical field of resin preparation, and particularly relates to a preparation method of low-temperature curing resin, which comprises the following steps: step 1, selecting raw materials: bisphenol A epoxy resin, a latent curing agent, a carbon nano tube, nano silicon dioxide, glass fiber, aluminum hydroxide, a dispersing agent and a lubricating agent; according to the preparation method of the low-temperature curing resin, the bisphenol A type epoxy resin and the latent curing agent are selected and combined with various fillers such as the carbon nano tube, the nano silicon dioxide, the glass fiber and the aluminum hydroxide, and the low-temperature rapid curing resin with excellent performance is prepared. The cured resin shows excellent mechanical properties, including high tensile strength, bending strength and impact toughness, which are benefited from the reinforcing effect of fillers such as carbon nanotubes, nano silicon dioxide and glass fibers. Meanwhile, the rigidity and the heat conductivity of the resin are remarkably improved, so that the stability and the heat-conducting property of the resin in a high-temperature environment are more excellent.

Description

Technical Field

[0001] The invention relates to the technical field of resin preparation, and in particular to a method for preparing a low-temperature curing resin. Background Art

[0002] In the current field of composite materials, traditional resin systems often require high-temperature baking during the curing process, which not only leads to an increase in energy consumption, but also easily generates internal stress during the curing process, causing material deformation or cracking, affecting the dimensional accuracy and structural integrity of the final product. In addition, the high-temperature curing cycle is long, which seriously affects production efficiency and prolongs the production cycle. At the same time, traditional resins have certain limitations in mechanical properties, thermal conductivity and chemical resistance, and it is difficult to meet the application requirements of high-performance composite materials in high-end fields such as aerospace and electronic packaging. Therefore, a method for preparing low-temperature curing resins is needed. Summary of the invention

[0003] Based on the existing technical problems, the present invention proposes a method for preparing a low-temperature curing resin.

[0004] The present invention provides a method for preparing a low-temperature curing resin, comprising the following steps: Step 1, selecting raw materials: bisphenol A epoxy resin, latent curing agent, carbon nanotubes, nano-silicon dioxide, glass fiber, aluminum hydroxide, dispersant, and lubricant.

[0005] Step 2: Filler pretreatment: Place the carbon nanotubes and nano-silicon dioxide in an oven to remove moisture from the filler.

[0006] Step 3, preparing resin: weigh 100g of bisphenol A epoxy resin in a glass container; add the pretreated carbon nanotubes into the bisphenol A epoxy resin, and use a high-speed disperser to stir at a speed of 1000rpm for 5 minutes to ensure that the carbon nanotubes are evenly dispersed.

[0007] Then add the pretreated nano-silica, increase the stirring speed to 1500 rpm, and continue stirring for 5 minutes.

[0008] Next, 6 g of glass fiber and 1 g of aluminum hydroxide were added, and the stirring speed was maintained at 1500 rpm for 10 minutes to allow all fillers to be fully mixed.

[0009] 4 g of latent curing agent was added, and stirring was continued at 1500 rpm for 5 minutes.

[0010] Finally, 0.5 g of lubricant was added, the stirring speed was reduced to 1000 rpm, and stirring was continued for 2 minutes.

[0011] Step 4: Degassing: Transfer the mixed resin to a vacuum degassing machine to remove the bubbles in the resin.

[0012] Step 5: Pouring and curing: Pour the degassed prepared resin into the preheated mold; place the mold in a constant temperature oven to complete the curing of the resin.

[0013] Preferably, in step 1, synthesis of bisphenol A type epoxy resin, bisphenol A, epichlorohydrin and alkali are selected; bisphenol A and epichlorohydrin are added into a reaction kettle, and a polycondensation reaction is carried out under the catalysis of NaOH to obtain bisphenol A type epoxy resin.

[0014] Preferably, in step 1, preparation of a latent curing agent, ethyleneamine, propyleneamine and a catalyst are selected; ethyleneamine and propyleneamine are mixed in a certain proportion and added to a reaction kettle; a catalyst is added and nitrogen is introduced, and the mixture is heated to a reaction temperature to carry out a polymerization reaction; after the reaction is completed, the mixture is cooled to room temperature, and the reaction liquid is filtered to obtain tetraethylenepentamine; and then distillation separation, acidification treatment, alkalization treatment and distillation purification are carried out to finally obtain a high-purity latent curing agent.

[0015] Preferably, the weight proportions of the materials selected in step one are: 100 g bisphenol A epoxy resin, 4 g latent curing agent, 2 g carbon nanotubes, 3 g nano-silicon dioxide, 6 g glass fiber, 1 g aluminum hydroxide, 1 g dispersant, and 0.5 g lubricant.

[0016] Preferably, in step 2, the drying temperature is set to 100° C. and the drying time is set to 12 hours.

[0017] Preferably, after the drying in step 2 is completed, the carbon nanotubes are placed in a high-speed disperser, 1 g of dispersant KH-550 is added, the processing speed is set to 2000 rpm, and the processing time is 30 minutes.

[0018] Preferably, after the drying in step 2 is completed, the nano-silicon dioxide is placed in a high-speed disperser, 1 g of dispersant KH-550 is added, the processing speed is set to 2000 rpm, and the processing time is 30 minutes.

[0019] Preferably, when the latent curing agent is added in step 3, the latent curing agent is controlled to be mixed when the bisphenol A epoxy resin is heated to 60°C.

[0020] Preferably, in step 4, the vacuum degree is set to 0.08 MPa and the degassing time is set to 15 minutes.

[0021] Preferably, in step five, the curing temperature is set to 120° C. and the curing time is set to 20 minutes.

[0022] The beneficial effects of the present invention are: This method uses bisphenol A epoxy resin and latent curing agent, combined with various fillers such as carbon nanotubes, nano-silica, glass fiber and aluminum hydroxide, to prepare a low-temperature fast-curing resin with excellent performance. The cured resin exhibits excellent mechanical properties, including high tensile strength, flexural strength and impact toughness, thanks to the reinforcing effect of fillers such as carbon nanotubes, nano-silica and glass fiber. At the same time, the stiffness and thermal conductivity of the resin are significantly improved, making its stability and thermal conductivity in high temperature environments more outstanding. The low-temperature curing process avoids stress concentration and deformation caused by high temperature, ensuring the accuracy of the resin size and the integrity of the structure. In addition, the use of latent curing agent achieves rapid curing, improves production efficiency and shortens the production cycle. The cured resin also exhibits good chemical resistance and weather resistance, and is suitable for a variety of harsh environments. Overall, the cured resin prepared by this method provides high strength and high performance while maintaining light weight, providing an ideal material solution for aerospace, electronic packaging and advanced manufacturing. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0024] A method for preparing a low-temperature curing resin comprises the following steps: Step 1, selecting raw materials: bisphenol A epoxy resin, latent curing agent, carbon nanotubes, nano silicon dioxide, glass fiber, aluminum hydroxide, dispersant, and lubricant.

[0025] In the synthesis of bisphenol A epoxy resin in step 1, bisphenol A, epichlorohydrin and alkali are selected; bisphenol A and epichlorohydrin are added into a reaction kettle, and a polycondensation reaction is carried out under the catalysis of NaOH to obtain bisphenol A epoxy resin.

[0026] In the preparation of the latent curing agent in step 1, ethyleneamine, propyleneamine and a catalyst are selected; ethyleneamine and propyleneamine are mixed in a certain proportion and added to a reaction kettle; the catalyst is added and nitrogen is introduced, and the mixture is heated to a reaction temperature to carry out a polymerization reaction; after the reaction is completed, the mixture is cooled to room temperature, and the reaction liquid is filtered to obtain tetraethylenepentamine; and then distillation separation, acidification treatment, alkalization treatment and distillation purification are carried out to finally obtain a high-purity latent curing agent.

[0027] The weight proportions of the materials selected in step 1 are: 100 g of bisphenol A epoxy resin, 4 g of latent curing agent, 2 g of carbon nanotubes, 3 g of nano-silicon dioxide, 6 g of glass fiber, 1 g of aluminum hydroxide, 1 g of dispersant, and 0.5 g of lubricant.

[0028] Step 2: Filler pretreatment: Place the carbon nanotubes and nano-silicon dioxide in an oven to remove moisture from the filler.

[0029] In step 2, the drying temperature is set to 100°C and the drying time is set to 12 hours.

[0030] Step 2: After drying, the carbon nanotubes were placed in a high-speed disperser, 1 g of dispersant KH-550 was added, and the processing speed was set to 2000 rpm and the processing time was 30 minutes.

[0031] After the drying of step 2 is completed, the nano-silicon dioxide is also placed in a high-speed disperser, 1 g of dispersant KH-550 is added, the processing speed is set to 2000 rpm, and the processing time is 30 minutes.

[0032] Step 3, preparing resin: weigh 100g of bisphenol A epoxy resin in a glass container; add the pretreated carbon nanotubes into the bisphenol A epoxy resin, and use a high-speed disperser to stir at a speed of 1000rpm for 5 minutes to ensure that the carbon nanotubes are evenly dispersed.

[0033] Then add the pretreated nano-silica, increase the stirring speed to 1500 rpm, and continue stirring for 5 minutes.

[0034] Next, 6 g of glass fiber and 1 g of aluminum hydroxide were added, and the stirring speed was maintained at 1500 rpm for 10 minutes to allow all fillers to be fully mixed.

[0035] 4 g of latent curing agent was added, and stirring was continued at 1500 rpm for 5 minutes.

[0036] When adding the latent curing agent in step 3, control the latent curing agent to mix when the bisphenol A epoxy resin is heated to 60°C. Finally, 0.5 g of lubricant was added, the stirring speed was reduced to 1000 rpm, and stirring was continued for 2 minutes.

[0037] Step 4: Degassing: Transfer the mixed resin to a vacuum degassing machine to remove the bubbles in the resin.

[0038] In step 4, the vacuum degree is set to 0.08 MPa and the degassing time is set to 15 minutes.

[0039] Step 5: Pouring and curing: Pour the degassed prepared resin into the preheated mold; place the mold in a constant temperature oven to complete the curing of the resin.

[0040] In step 5, the curing temperature is set to 120°C and the curing time is set to 20 minutes.

[0041] This method uses bisphenol A epoxy resin and latent curing agent, combined with various fillers such as carbon nanotubes, nano-silica, glass fiber and aluminum hydroxide, to prepare a low-temperature fast-curing resin with excellent performance. The cured resin exhibits excellent mechanical properties, including high tensile strength, flexural strength and impact toughness, thanks to the reinforcing effect of fillers such as carbon nanotubes, nano-silica and glass fiber. At the same time, the stiffness and thermal conductivity of the resin are significantly improved, making its stability and thermal conductivity in high temperature environments more outstanding. The low-temperature curing process avoids stress concentration and deformation caused by high temperature, ensuring the accuracy of the resin size and the integrity of the structure. In addition, the use of latent curing agent achieves rapid curing, improves production efficiency and shortens the production cycle. The cured resin also exhibits good chemical resistance and weather resistance, and is suitable for a variety of harsh environments. Overall, the cured resin prepared by this method provides high strength and high performance while maintaining light weight, providing an ideal material solution for aerospace, electronic packaging and advanced manufacturing.

[0042] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for preparing a low temperature curing resin, characterized in that: The method comprises the following steps: Step 1, selecting raw materials: bisphenol A epoxy resin, latent curing agent, carbon nanotubes, nano silicon dioxide, glass fiber, aluminum hydroxide, dispersant, and lubricant; Step 2: Filler pretreatment: Place the carbon nanotubes and nano-silicon dioxide in an oven to remove moisture from the filler; Step 3, preparing resin: weigh 100g of bisphenol A epoxy resin in a glass container; add the pretreated carbon nanotubes to the bisphenol A epoxy resin, and use a high-speed disperser to stir at a speed of 1000rpm for 5 minutes to ensure that the carbon nanotubes are evenly dispersed; Then add the pretreated nano-silica, increase the stirring speed to 1500 rpm, and continue stirring for 5 minutes; Next, add 6 g of glass fiber and 1 g of aluminum hydroxide, maintain the speed of 1500 rpm, and stir for 10 minutes to make all the fillers fully mixed; Add 4 g of latent curing agent and continue stirring at 1500 rpm for 5 minutes; Finally, 0.5 g of lubricant was added, the stirring speed was reduced to 1000 rpm, and stirring was continued for 2 min; Step 4: Degassing: Transfer the mixed resin to a vacuum degassing machine to remove bubbles in the resin; Step 5: Pouring and curing: Pour the degassed prepared resin into the preheated mold; place the mold in a constant temperature oven to complete the curing of the resin.

2. The method for preparing a low temperature curing resin according to claim 1, characterized in that: Step 1, synthesis of bisphenol A type epoxy resin, select bisphenol A, epichlorohydrin, and alkali; add bisphenol A and epichlorohydrin into a reaction kettle, and carry out polycondensation reaction under the catalysis of NaOH to obtain bisphenol A type epoxy resin.

3. The method for preparing a low temperature curing resin according to claim 1, characterized in that: Step 1, preparation of a latent curing agent, selecting ethyleneamine, propyleneamine, and a catalyst; mixing ethyleneamine and propyleneamine in a certain proportion and adding them to a reaction kettle; adding a catalyst and introducing nitrogen, heating to a reaction temperature for a polymerization reaction; after the reaction is completed, cooling to room temperature, filtering the reaction liquid to obtain tetraethylenepentamine; then performing distillation separation, acidification treatment, alkalization treatment and distillation purification, and finally obtaining a high-purity latent curing agent.

4. The method for preparing a low temperature curing resin according to claim 1, characterized in that: The weight proportions of the materials selected in step 1 are: 100 g of bisphenol A epoxy resin, 4 g of latent curing agent, 2 g of carbon nanotubes, 3 g of nano-silicon dioxide, 6 g of glass fiber, 1 g of aluminum hydroxide, 1 g of dispersant, and 0.5 g of lubricant.

5. The method for preparing a low temperature curing resin according to claim 1, characterized in that: In step 2, the drying temperature is set to 100°C and the drying time is set to 12 hours.

6. The method for preparing a low temperature curing resin according to claim 1, characterized in that: Step 2: After drying, the carbon nanotubes were placed in a high-speed disperser, 1 g of dispersant KH-550 was added, and the processing speed was set to 2000 rpm and the processing time was 30 minutes.

7. The method for preparing a low temperature curing resin according to claim 1, characterized in that: After the drying of step 2 is completed, the nano-silicon dioxide is also placed in a high-speed disperser, 1 g of dispersant KH-550 is added, the processing speed is set to 2000 rpm, and the processing time is 30 minutes.

8. The method for preparing a low temperature curing resin according to claim 1, characterized in that: When the latent curing agent is added in step 3, the latent curing agent is controlled to be mixed when the bisphenol A epoxy resin is heated to 60°C.

9. The method for preparing a low temperature curing resin according to claim 1, characterized in that: In step 4, the vacuum degree is set to 0.08 MPa and the degassing time is set to 15 minutes.

10. The method for preparing a low temperature curing resin according to claim 1, characterized in that: In step 5, the curing temperature is set to 120°C and the curing time is set to 20 minutes.