阅读说明：本技术 一种环氧树脂固化剂及制备方法 (Epoxy resin curing agent and preparation method thereof ) 是由 冯磊 张双柱 葛正国 于 2020-08-04 设计创作，主要内容包括：本发明公开了一种环氧树脂固化剂及制备方法,该环氧树脂固化剂包括如下重量份原料：组分A3-5份,组分B3-5份,碳纳米管30-50份；组分A具有很好的耐挥发性,在使用过程中不会出现挥发,进而保护使用者不会被迫吸食造成人体损伤；该组分B以甲基丙烯酸甲酯和丙烯酸丁酯为原料制得丙烯酸微球乳液,丙烯酸树脂本身具有很好的耐水性,进一步用正硅酸乙酯,使得丙烯酸表面连接纳米硅,进而γ-氨丙基三乙氧基硅烷发生水解产生硅醇,与丙烯酸/纳米硅复合微球表面的活性基团进行反应,产生硅氧键提升了耐水效果,使得组分A和组分B进一步嵌入碳纳米管中制得的固化剂,具有很好的耐水性且不易挥发,且能够增加环氧树脂的强度。(The invention discloses an epoxy resin curing agent and a preparation method thereof, wherein the epoxy resin curing agent comprises the following raw materials in parts by weight: 3-5 parts of component A, 3-5 parts of component B and 30-50 parts of carbon nano tube; the component A has good volatility resistance, and can not volatilize in the using process, so that the user can be protected from being forced to suck to cause human body injury; the component B is prepared by taking methyl methacrylate and butyl acrylate as raw materials to prepare acrylic acid microsphere emulsion, the acrylic resin has good water resistance, and further ethyl orthosilicate is used for connecting nano silicon on the surface of acrylic acid, so that gamma-aminopropyl triethoxysilane is hydrolyzed to generate silanol which reacts with active groups on the surface of the acrylic acid/nano silicon composite microsphere to generate silicon-oxygen bonds to improve the water resistance effect, so that the component A and the component B are further embedded into the curing agent prepared from the carbon nano tubes, and the acrylic acid microsphere emulsion has good water resistance and is not easy to volatilize, and can increase the strength of epoxy resin.)

1. An epoxy resin curing agent, which is characterized in that: the feed comprises the following raw materials in parts by weight: 3-5 parts of component A, 3-5 parts of component B and 30-50 parts of carbon nano tube;

the epoxy resin curing agent is prepared by the following steps:

step S1: adding carbon nano tubes into mixed acid, carrying out ultrasonic treatment for 1-1.5h under the conditions that the temperature is 60-65 ℃ and the frequency is 30-50kHz, then heating to 90-100 ℃, carrying out heat preservation for 3-5h, adding deionized water until the pH value is 6-7, centrifuging the filtrate for 5-10min under the condition that the rotation speed is 10000-12000r/min to remove supernatant, washing precipitates with deionized water until the pH value of a cleaning solution is 7, and drying to obtain modified carbon nano tubes;

step S2: adding the modified carbon nano tube prepared in the step S1 into deionized water, dispersing until the modified carbon nano tube is uniformly dispersed, adding the component A and the component B, stirring for 30-40min under the condition that the rotating speed is 300-500r/min, carrying out ultrasonic treatment for 1-1.5h under the condition that the frequency is 1-3MHz, filtering to remove filtrate, and drying the filter cake for 5-10h under the condition that the temperature is 70-80 ℃ to prepare the epoxy resin curing agent.

2. The epoxy resin curing agent according to claim 1, wherein: the mixed acid is prepared by mixing a sulfuric acid solution and a nitric acid solution in a volume ratio of 3:1, wherein the mass fraction of the sulfuric acid solution is 70-75%, and the mass fraction of the nitric acid solution is 60-70%.

3. The epoxy resin curing agent according to claim 1, wherein: the component A is prepared by the following steps:

step A1: introducing chlorine gas into an isopropyl benzene reaction kettle under the illumination condition of the rotation speed of 100-;

step A2: adding monoethyl phthalate into tetrahydrofuran, stirring at the rotation speed of 150-200r/min until the monoethyl phthalate is completely dissolved, adding benzotriazole-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate and the intermediate 1 prepared in the step A1, continuously stirring for 2-3h at the temperature of 25-30 ℃, removing tetrahydrofuran under the vacuum condition, adding reactants into dichloromethane at the temperature of 85-90 ℃ until the reactants are completely dissolved, washing with a saturated sodium carbonate solution, standing for layering, drying with sodium sulfate, and distilling at the temperature of 85-90 ℃ to prepare an intermediate 2;

step A3: adding the intermediate 2 prepared in the step A2 and tetrahydrofuran into a reaction kettle, continuously stirring until the intermediate 2 is completely dissolved, adding a nitric acid solution into the reaction kettle, reacting at the rotation speed of 100-120r/min and the temperature of 60-65 ℃ to prepare an intermediate 3, adding the intermediate 3, iron powder and a hydrochloric acid solution into the reaction kettle, and reacting at the temperature of 30-40 ℃ for 1-1.5h to prepare an intermediate 4;

step A4: adding tetrabutyl titanate and ethanol into a reaction kettle, stirring until the tetrabutyl titanate and the ethanol are uniformly mixed, adding kaolin powder, carrying out ultrasonic treatment for 30-40min under the condition of the frequency of 30-50kHz, stirring for 30-40min under the conditions of the rotation speed of 300-80 ℃ and the temperature of 78-83 ℃, filtering to remove filtrate, adding a filter cake into deionized water, dispersing until the filtrate is uniformly dispersed, adding 4-dimethylaminopyridine and the intermediate 4 prepared in the step A3, stirring for 8-10h under the conditions of the rotation speed of 100-150r/min and the temperature of 40-50 ℃, filtering to remove the filtrate to obtain carrier amine, adding hydrazine hydrate and the ethanol into the reaction kettle, stirring until the hydrazine hydrate and the ethanol are uniformly mixed, adding the carrier amine, refluxing for 5-8h under the condition of the temperature of 80-85 ℃, the filtrate was removed by filtration to give component A.

4. The epoxy resin curing agent according to claim 3, wherein: the dosage of cumene and chlorine in the step A1 is 1:1, the dosage ratio of monoethyl phthalate, tetrahydrofuran, benzotriazole-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate and the intermediate 1 in the step A2 is 2-2.3g:10mL:3g:1.3-1.5mL, the dosage ratio of the intermediate 2 and nitric acid solution in the step A3 is 1:1-1.2, the mass fraction of the nitric acid solution is 30-40%, the dosage of the intermediate 3 and hydrochloric acid solution is 2-3g:5mL, the mass fraction of the hydrochloric acid solution is 10-15%, the dosage of iron powder is 3-5% of the mass of the intermediate 3, the dosage of tetrabutyl titanate in the step A4 is 3-3.5% of the mass of kaolin powder, the dosage of the filter cake and the intermediate 4 is 1-1.5g:3mL, the dosage of the 4-dimethylamino pyridine is 5-10% of the mass of the intermediate 4.

5. The epoxy resin curing agent according to claim 1, wherein: the component B is prepared by the following steps:

step B1: adding methyl methacrylate, butyl acrylate and potassium persulfate into a reaction kettle, mixing to prepare a mixed solution, adding xylene into the reaction kettle, stirring and dropwise adding the mixed solution at the conditions of the rotation speed of 150-;

step B2: regulating the pH value of the acrylic acid microsphere emulsion prepared in the step B1 to 4-5, adding tetraethoxysilane into the acrylic acid microsphere emulsion, carrying out heat preservation for 15-20h at the temperature of 50-60 ℃, centrifuging for 5-8min at the rotation speed of 4000-5000r/min, removing supernatant, washing the precipitate with deionized water for 2-3 times, and washing for 30-50s each time to prepare acrylic acid/nano silicon composite microspheres;

step B3: and D, adding the acrylic acid/nano-silicon composite microspheres prepared in the step B2 into tetrahydrofuran, dispersing until the acrylic acid/nano-silicon composite microspheres are uniformly dispersed, adding gamma-aminopropyl triethoxysilane, ethanol and sodium dodecyl benzene sulfonate, stirring for 30-40min at the rotation speed of 200-300r/min and the temperature of 40-50 ℃, heating to 60-65 ℃, adding ammonium persulfate, continuously stirring for 3-6h, and distilling to remove ethanol and tetrahydrofuran at the temperature of 80-90 ℃ to obtain the component B.

6. The epoxy resin curing agent according to claim 5, wherein: the mass ratio of the methyl methacrylate, the butyl acrylate and the potassium persulfate in the step B1 is 4:3:0.4-0.6, the mass ratio of the xylene to the mixed solution is 1:1, the mass of the toluene solution is 14-16% of the mass of the xylene, the toluene solution is toluene containing 0.5-0.8 mass percent of potassium persulfate, the mass ratio of the ethyl orthosilicate in the step B2 is 10-15% of the mass of the acrylic microsphere emulsion, the mass ratio of the gamma-aminopropyltriethoxysilane, the ethanol and the sodium dodecyl benzene sulfonate in the step B3 is 5mL:10mL:0.1-0.3g, and the mass ratio of the gamma-aminopropyltriethoxysilane is 3-5% of the mass of the acrylic acid/nano silicon composite microsphere.

7. The method for preparing an epoxy resin curing agent according to claim 1, wherein: the method specifically comprises the following steps:

step S1: adding carbon nano tubes into mixed acid, carrying out ultrasonic treatment for 1-1.5h under the conditions that the temperature is 60-65 ℃ and the frequency is 30-50kHz, then heating to 90-100 ℃, carrying out heat preservation for 3-5h, adding deionized water until the pH value is 6-7, centrifuging the filtrate for 5-10min under the condition that the rotation speed is 10000-12000r/min to remove supernatant, washing precipitates with deionized water until the pH value of a cleaning solution is 7, and drying to obtain modified carbon nano tubes;

step S2: adding the modified carbon nano tube prepared in the step S1 into deionized water, dispersing until the modified carbon nano tube is uniformly dispersed, adding the component A and the component B, stirring for 30-40min under the condition that the rotating speed is 300-500r/min, carrying out ultrasonic treatment for 1-1.5h under the condition that the frequency is 1-3MHz, filtering to remove filtrate, and drying the filter cake for 5-10h under the condition that the temperature is 70-80 ℃ to prepare the epoxy resin curing agent.

Technical Field

The invention belongs to the technical field of curing agent preparation, and particularly relates to an epoxy resin curing agent and a preparation method thereof.

Background

Epoxy resins are prepolymers of thermoplastic polymers, which have excellent mechanical and thermal properties and are widely used in various fields. The epoxy resin is thermoplastic linear structure, and after being heated, the solid resin can be softened and melted to be changed into viscous state or liquid state, and the viscosity of the liquid resin is reduced after being heated. The epoxy resin must react with the curing agent to convert the epoxy resin into a high polymer with a three-dimensional reticular cubic structure, and then the epoxy resin shows a series of excellent performances, so that the structure and the quality of the curing agent directly influence the application effect of the epoxy resin.

The existing epoxy resin curing agent has high volatility, so that a user can be forced to suck the curing agent when the curing agent is used, the human body is injured, the curing agent is subjected to water soaking after the epoxy resin is immobilized, and the curing agent is precipitated due to poor water resistance of the curing agent, so that the use performance of the epoxy resin is reduced.

Disclosure of Invention

The invention aims to provide an epoxy resin curing agent and a preparation method thereof.

The technical problems to be solved by the invention are as follows:

the existing epoxy resin curing agent has high volatility, so that a user can be forced to suck the curing agent when the curing agent is used, the human body is injured, the curing agent is subjected to water soaking after the epoxy resin is immobilized, and the curing agent is precipitated due to poor water resistance of the curing agent, so that the use performance of the epoxy resin is reduced.

The purpose of the invention can be realized by the following technical scheme:

an epoxy resin curing agent comprises the following raw materials in parts by weight: 3-5 parts of component A, 3-5 parts of component B and 30-50 parts of carbon nano tube;

the epoxy resin curing agent is prepared by the following steps:

step S1: adding carbon nano tubes into mixed acid, carrying out ultrasonic treatment for 1-1.5h under the conditions that the temperature is 60-65 ℃ and the frequency is 30-50kHz, then heating to 90-100 ℃, carrying out heat preservation for 3-5h, adding deionized water until the pH value is 6-7, centrifuging the filtrate for 5-10min under the condition that the rotation speed is 10000-12000r/min to remove supernatant, washing precipitates with deionized water until the pH value of a cleaning solution is 7, and drying to obtain modified carbon nano tubes;

step S2: adding the modified carbon nano tube prepared in the step S1 into deionized water, dispersing until the modified carbon nano tube is uniformly dispersed, adding the component A and the component B, stirring for 30-40min under the condition that the rotating speed is 300-500r/min, carrying out ultrasonic treatment for 1-1.5h under the condition that the frequency is 1-3MHz, filtering to remove filtrate, and drying the filter cake for 5-10h under the condition that the temperature is 70-80 ℃ to prepare the epoxy resin curing agent.

Further, the mixed acid is prepared by mixing a sulfuric acid solution and a nitric acid solution in a volume ratio of 3:1, wherein the mass fraction of the sulfuric acid solution is 70-75%, and the mass fraction of the nitric acid solution is 60-70%.

Further, the component A is prepared by the following steps:

step A1: introducing chlorine gas into an isopropyl benzene reaction kettle under the illumination condition of the rotation speed of 100-;

the reaction process is as follows:

step A2: adding monoethyl phthalate into tetrahydrofuran, stirring at the rotation speed of 150-200r/min until the monoethyl phthalate is completely dissolved, adding benzotriazole-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate and the intermediate 1 prepared in the step A1, continuously stirring for 2-3h at the temperature of 25-30 ℃, removing tetrahydrofuran under the vacuum condition, adding reactants into dichloromethane at the temperature of 85-90 ℃ until the reactants are completely dissolved, washing with a saturated sodium carbonate solution, standing for layering, drying with sodium sulfate, and distilling at the temperature of 85-90 ℃ to prepare an intermediate 2;

the reaction process is as follows:

step A3: adding the intermediate 2 prepared in the step A2 and tetrahydrofuran into a reaction kettle, continuously stirring until the intermediate 2 is completely dissolved, adding a nitric acid solution into the reaction kettle, reacting at the rotation speed of 100-120r/min and the temperature of 60-65 ℃ to prepare an intermediate 3, adding the intermediate 3, iron powder and a hydrochloric acid solution into the reaction kettle, and reacting at the temperature of 30-40 ℃ for 1-1.5h to prepare an intermediate 4;

the reaction process is as follows:

step A4: adding tetrabutyl titanate and ethanol into a reaction kettle, stirring until the tetrabutyl titanate and the ethanol are uniformly mixed, adding kaolin powder, carrying out ultrasonic treatment for 30-40min under the condition of the frequency of 30-50kHz, stirring for 30-40min under the conditions of the rotation speed of 300-80 ℃ and the temperature of 78-83 ℃, filtering to remove filtrate, adding a filter cake into deionized water, dispersing until the filtrate is uniformly dispersed, adding 4-dimethylaminopyridine and the intermediate 4 prepared in the step A3, stirring for 8-10h under the conditions of the rotation speed of 100-150r/min and the temperature of 40-50 ℃, filtering to remove the filtrate to obtain carrier amine, adding hydrazine hydrate and the ethanol into the reaction kettle, stirring until the hydrazine hydrate and the ethanol are uniformly mixed, adding the carrier amine, refluxing for 5-8h under the condition of the temperature of 80-85 ℃, the filtrate was removed by filtration to give component A.

Further, the dosage of cumene and chlorine in the step A1 is 1:1, the dosage ratio of the monoethyl phthalate, tetrahydrofuran, benzotriazole-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate and the intermediate 1 in the step A2 is 2-2.3g:10mL:3g:1.3-1.5mL, the dosage ratio of the intermediate 2 and nitric acid solution in the step A3 is 1:1-1.2, the mass fraction of the nitric acid solution is 30-40%, the dosage of the intermediate 3 and hydrochloric acid solution is 2-3g:5mL, the mass fraction of the hydrochloric acid solution is 10-15%, the dosage of iron powder is 3-5% of the mass of the intermediate 3, the dosage of tetrabutyl titanate in the step A4 is 3-3.5% of the mass of kaolin powder, the dosage of the filter cake and the intermediate 4 is 1-1.5g:3mL, the dosage of the 4-dimethylamino pyridine is 5-10% of the mass of the intermediate 4.

Further, the component B is prepared by the following steps:

step B1: adding methyl methacrylate, butyl acrylate and potassium persulfate into a reaction kettle, mixing to prepare a mixed solution, adding xylene into the reaction kettle, stirring and dropwise adding the mixed solution at the conditions of the rotation speed of 150-;

step B2: regulating the pH value of the acrylic acid microsphere emulsion prepared in the step B1 to 4-5, adding tetraethoxysilane into the acrylic acid microsphere emulsion, carrying out heat preservation for 15-20h at the temperature of 50-60 ℃, centrifuging for 5-8min at the rotation speed of 4000-5000r/min, removing supernatant, washing the precipitate with deionized water for 2-3 times, and washing for 30-50s each time to prepare acrylic acid/nano silicon composite microspheres;

step B3: and D, adding the acrylic acid/nano-silicon composite microspheres prepared in the step B2 into tetrahydrofuran, dispersing until the acrylic acid/nano-silicon composite microspheres are uniformly dispersed, adding gamma-aminopropyl triethoxysilane, ethanol and sodium dodecyl benzene sulfonate, stirring for 30-40min at the rotation speed of 200-300r/min and the temperature of 40-50 ℃, heating to 60-65 ℃, adding ammonium persulfate, continuously stirring for 3-6h, and distilling to remove ethanol and tetrahydrofuran at the temperature of 80-90 ℃ to obtain the component B.

Further, the mass ratio of the methyl methacrylate, the butyl acrylate and the potassium persulfate in the step B1 is 4:3:0.4-0.6, the mass ratio of the xylene to the mixed solution is 1:1, the mass of the toluene solution is 14-16% of that of the xylene, the toluene solution is toluene containing 0.5-0.8% of potassium persulfate, the mass ratio of the ethyl orthosilicate in the step B2 is 10-15% of that of the acrylic microsphere emulsion, the mass ratio of the gamma-aminopropyltriethoxysilane, the ethanol and the sodium dodecylbenzene sulfonate in the step B3 is 5mL:10mL:0.1-0.3g, and the mass ratio of the gamma-aminopropyltriethoxysilane is 3-5% of that of the acrylic acid/nano silicon composite microspheres.

A preparation method of an epoxy resin curing agent specifically comprises the following steps:

step S1: adding carbon nano tubes into mixed acid, carrying out ultrasonic treatment for 1-1.5h under the conditions that the temperature is 60-65 ℃ and the frequency is 30-50kHz, then heating to 90-100 ℃, carrying out heat preservation for 3-5h, adding deionized water until the pH value is 6-7, centrifuging the filtrate for 5-10min under the condition that the rotation speed is 10000-12000r/min to remove supernatant, washing precipitates with deionized water until the pH value of a cleaning solution is 7, and drying to obtain modified carbon nano tubes;

step S2: adding the modified carbon nano tube prepared in the step S1 into deionized water, dispersing until the modified carbon nano tube is uniformly dispersed, adding the component A and the component B, stirring for 30-40min under the condition that the rotating speed is 300-500r/min, carrying out ultrasonic treatment for 1-1.5h under the condition that the frequency is 1-3MHz, filtering to remove filtrate, and drying the filter cake for 5-10h under the condition that the temperature is 70-80 ℃ to prepare the epoxy resin curing agent.

The invention has the beneficial effects that: the invention prepares a component A in the process of preparing an epoxy resin curing agent, isopropyl benzene is taken as a raw material, substitution reaction is carried out on isopropyl benzene and chlorine under the illumination condition to convert two hydrogen on isopropyl into chlorine, then the isopropyl benzene and liquid ammonia react to convert chlorine into amino to prepare an intermediate 1, further phthalic acid monoethyl ester is used to protect two amino groups on the intermediate to prepare an intermediate 2, the intermediate 2 is inserted into nitro group at para position of benzene ring under the action of nitric acid solution to prepare an intermediate 3, further iron powder is used to reduce nitro group into amino group to prepare an intermediate 4, kaolin powder is modified by tetrabutyl titanate to convert hydroxyl on the surface of the kaolin powder into carboxyl, and then amidation reaction is carried out on the intermediate 4 under the action of 4-dimethylamino pyridine to fix molecules of the intermediate 4 on the surface of the kaolin powder, and then hydrazine hydrate is used for deprotection, so that the protected amino group is deprotected, compared with the traditional amine curing agent, the component A has good volatility resistance, and can not volatilize in the use process, thereby protecting a user from being forced to absorb to cause human body damage; and a component B is prepared, the component B takes methyl methacrylate and butyl acrylate as raw materials to prepare acrylic acid microsphere emulsion, the acrylic resin has good water resistance, the acrylic acid surface is further connected with nano silicon by using ethyl orthosilicate, and then the gamma-aminopropyl triethoxysilane is hydrolyzed to generate silanol which reacts with active groups on the surface of the acrylic acid/nano silicon composite microsphere to generate silicon-oxygen bonds to improve the water resistance effect, so that the component A and the component B are further embedded into the carbon nano tube to prepare the curing agent, and the curing agent has good water resistance and is difficult to volatilize, and can increase the strength of the epoxy resin.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.