A high-toughness epoxy resin material and its preparation method

Abstract

This invention relates to the field of resin composite materials technology, specifically disclosing a high-toughness epoxy resin material and its preparation method. The high-toughness epoxy resin material, by weight, comprises: 40-60 parts epoxy resin A, 20-30 parts epoxy resin B, 20-40 parts epoxy resin C, 25-30 parts thermoplastic resin, 8-10 parts toughening agent, and 7-12 parts curing agent; the total weight of epoxy resin A, epoxy resin B, and epoxy resin C is 100 parts. Different types, epoxy groups, and molecular weights of epoxy resins are mixed as the matrix, further increasing the toughness of the resin matrix while considering both processability and performance. By controlling the compatibility and content of the thermoplastic resin, an inversion occurs between it and the epoxy resin, forming more interfaces. Monodisperse nanoparticles can effectively fill the free volume of the epoxy resin, simultaneously improving the mechanical properties and heat resistance of the resin, achieving the purpose of strengthening and toughening.

Description

Technical Field

[0001] This invention relates to the field of resin composite materials technology, and in particular to a high-toughness epoxy resin material and its preparation method. Background Technology

[0002] The rotors in aero engines typically operate at very high speeds. When struck by birds or hail, the engine blades are prone to breakage. Blade fragments can impact the casing containment ring. If the containment ring's strength is insufficient, the fragments can penetrate it, potentially damaging critical components such as the aircraft cabin, fuel tanks, hydraulic lines, and control circuits, severely jeopardizing flight safety. Ordinary epoxy resin matrices are brittle, resulting in prepregs with low structural strength and prone to interlayer cracking, making them unsuitable for the requirements of aero engine containment rings. Therefore, it is necessary to develop a high-toughness resin matrix that meets the requirements of engine casings. Summary of the Invention

[0003] In order to overcome the shortcomings of the prior art, the purpose of this invention is to provide a high-toughness epoxy resin material and its preparation method, so as to improve the mechanical properties of the resin.

[0004] The technical solution adopted in this invention is as follows:

[0005] In a first aspect, a high-toughness epoxy resin material, comprising, by weight parts:

[0006] 40-60 parts of epoxy resin A, 20-30 parts of epoxy resin B, 20-40 parts of epoxy resin C, 25-30 parts of thermoplastic resin, 8-10 parts of toughening agent, and 7-12 parts of curing agent;

[0007] The total weight of epoxy resin A, epoxy resin B, and epoxy resin C is 100 parts.

[0008] By using a mixture of epoxy resins of different types, epoxy groups, and molecular weights as the matrix, the toughness of the resin matrix is ​​further increased while taking into account both process and performance. The compatibility and content of thermoplastic resin are controlled to induce an inversion between the thermoplastic resin and the epoxy resin, forming more interfaces. Monodisperse nanoparticles can effectively fill the free volume of epoxy resin. Nanoparticles have nano-size effects, extremely large specific surface area, and strong interfacial interactions, giving them a high chance of physical or chemical bonding with epoxy molecular chains. This results in an ideal interface with forces much greater than van der Waals forces and moderate bonding strength, which causes particles to absorb energy and initiate microcracks. As crazes propagate in the epoxy resin, they are passivated and hindered by rigid particles, preventing destructive cracking. This achieves toughening of the epoxy resin, while also improving its heat resistance.

[0009] Optionally, the epoxy resin A is a low-viscosity epoxy resin, and the viscosity of the epoxy resin A is 300-900 mPa·s;

[0010] The epoxy resin A is one of resorcinol diglycidyl ether and bisphenol F diglycidyl ether.

[0011] Excessive viscosity is not conducive to the laying of epoxy resin materials, while insufficient viscosity causes severe resin flow in composite materials, making it impossible to accurately control the resin content and affecting the interlayer performance of the materials.

[0012] Optionally, the epoxy resin B is one or a mixture of several of the following: triglycidyl-p-aminophenol, triglycidyl-m-aminophenol, and triglycidyl ether triphenylmethane.

[0013] Optionally, the epoxy resin C is one or a mixture of several of bisphenol A diglycidyl ether, 4,5-epoxycyclohexane-1,2-dicarboxylic acid diglycidyl ester, and 1,2-cyclohexanedicarboxylic acid diglycidyl ester.

[0014] Optionally, the thermoplastic resin has a molecular weight ≤20000, and the thermoplastic resin is one or a mixture of several of polyethersulfone, polysulfone, polyphenylene ether, and polyaryletherketone.

[0015] When the thermoplastic resin content is low, the thermosetting / thermoplastic blend system will form an island phase with the thermoplastic resin-rich dispersed island phase and the thermosetting resin-rich continuous sea phase. As the content increases, the size of the thermoplastic-rich particles in the island phase continues to increase, and the phase structure will gradually transition from the island phase to a mixed state of island phase and bicontinuous phase. When the content continues to increase, the blend system undergoes phase inversion, forming an inversion structure in which interconnected thermosetting resin-rich particles are distributed in the thermoplastic resin-rich region. The inversion structure and bicontinuous phase exhibit higher toughness than the island phase and are necessary conditions for obtaining a high-toughness system.

[0016] Optionally, the toughening agent is one or a mixture of several of the following: core-shell structured nanospheres, nano-silica particles, nano-zinc oxide, and graphene.

[0017] The curing agent is one of dicyandiamide, diaminodiphenyl sulfone, and diaminodiphenylmethane.

[0018] Core-shell structured nanospheres can induce crazes and shear bands in epoxy resin materials to absorb energy. When rigid particles undergo plastic deformation, they can effectively inhibit the propagation of numerical cracks in the material and absorb energy, thereby achieving the purpose of toughening the material.

[0019] Optionally, the epoxy resin material has a tensile strength ≥80MPa, an elongation at break ≥3.5%, and an impact strength ≥20kJ / m. 2 Flexural strength ≥130MPa.

[0020] Secondly, a method for preparing a high-toughness epoxy resin material includes the following steps:

[0021] S1. Mix resin B with thermoplastic resin and stir at high temperature to obtain mixed component A;

[0022] S2. The toughening agent is dispersed into resin A at room temperature to obtain mixed component B;

[0023] S3, the curing agent and resin C are stirred at room temperature and then ground by a three-roll mill to obtain mixed component C;

[0024] S4. Cool down the mixed component A system, add mixed components B and C and stir to obtain a high-toughness epoxy resin matrix for winding prepreg;

[0025] S5. Obtain epoxy resin material.

[0026] Optionally, the stirring temperature in step S1 is 110-130℃;

[0027] The dispersion time in step S2 is 15-30 minutes;

[0028] The stirring temperature in step S3 is 20-40℃.

[0029] Optionally, the mixed component A system is cooled to 60-80°C.

[0030] The beneficial effects of this invention are as follows:

[0031] The epoxy resin matrix is ​​toughened by combining thermoplastic resin and nanoparticles in multiple layers, methods, and dimensions. The thermoplastic resin is distributed in the resin matrix and can undergo phase inversion during the curing process to generate more interfaces, effectively improving the toughness of the epoxy resin matrix. Monodisperse nanoparticles can effectively fill the free volume of the epoxy resin, thereby improving the mechanical properties and heat resistance of the resin at the same time, achieving the purpose of strengthening and toughening. Detailed Implementation

[0032] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0033] Example

[0034] A high-toughness epoxy resin material is prepared by the following steps:

[0035] S1: Add 30 parts of triglycidyl-p-aminophenol to a planetary stirred reactor and heat to 120°C; then add 28 parts of polyarylether ketone and stir for 2 hours to obtain mixed component A.

[0036] S2: Add 10 parts of organosilicon core-shell particles and 50 parts of resorcinol diglycidyl ether, and disperse mechanically at high speed for 30 minutes to obtain mixed slurry B.

[0037] S3: Add 10 parts of dicyandiamide and 20 parts of bisphenol A diglycidyl ether at room temperature and stir at room temperature for 20 minutes; grind the stirred components into mixed component C by a three-roll mill.

[0038] S4: Cool the system temperature of step S1 to 70℃; add mixed components B and C, and stir in the reactor for 30 minutes to obtain the high-toughness epoxy resin matrix of the composite prepreg.

[0039] Example 2

[0040] A high-toughness epoxy resin material is prepared by the following steps:

[0041] S1: Add 30 parts of triglycidyl-m-aminophenol to a planetary stirred reactor and heat to 120°C; then add 28 parts of polysulfone and stir for 2 hours to obtain mixed component A.

[0042] S2: Add 10 parts of organosilicon core-shell particles and 50 parts of bisphenol F diglycidyl ether, and disperse mechanically at high speed for 30 minutes to obtain mixed slurry B.

[0043] S3: Add 10 parts of dicyandiamide and 20 parts of 4,5-epoxycyclohexane-1,2-dicarboxylic acid diglycidyl ester at room temperature and stir at room temperature for 20 minutes; grind the stirred components into mixed component C by a three-roll mill.

[0044] S4: Cool the system temperature of step S1 to 70℃; add mixed components B and C, and stir in the reactor for 30 minutes to obtain the high-toughness epoxy resin matrix of the composite prepreg.

[0045] Example 3

[0046] A high-toughness epoxy resin material is prepared by the following steps:

[0047] S1: Add 20 parts of triglycidyl-p-aminophenol to a planetary stirred reactor and heat to 120°C; then add 28 parts of polyarylether ketone and stir for 2 hours to obtain mixed component A.

[0048] S2: Add 10 parts of organosilicon core-shell particles and 50 parts of resorcinol diglycidyl ether, and disperse mechanically at high speed for 30 minutes to obtain mixed slurry B.

[0049] S3: Add 10 parts of dicyandiamide and 30 parts of bisphenol A diglycidyl ether at room temperature and stir at room temperature for 20 minutes; grind the stirred components into mixed component C by a three-roll mill.

[0050] S4: Cool the system temperature of step S1 to 70℃; add mixed components B and C, and stir in the reactor for 30 minutes to obtain the high-toughness epoxy resin matrix of the composite prepreg.

[0051] Example 4

[0052] A high-toughness epoxy resin material is prepared by the following steps:

[0053] S1: Add 20 parts of triglycidyl-m-aminophenol to a planetary stirred reactor and heat to 120°C; then add 28 parts of polysulfone and stir for 2 hours to obtain mixed component A.

[0054] S2: Add 10 parts of nano silica particles and 50 parts of bisphenol F diglycidyl ether, and disperse mechanically at high speed for 30 minutes to obtain mixed slurry B.

[0055] S3: Add 10 parts of dicyandiamide and 30 parts of 4,5-epoxycyclohexane-1,2-dicarboxylic acid diglycidyl ester at room temperature and stir at room temperature for 20 minutes; grind the stirred components into mixed component C by a three-roll mill.

[0056] S4: Cool the system temperature of step S1 to 70℃; add mixed components B and C, and stir in the reactor for 30 minutes to obtain the high-toughness epoxy resin matrix of the composite prepreg.

[0057] Comparative Example

[0058] Comparative Example 1

[0059] A high-toughness epoxy resin material, which differs from Example 1 in that the amount of polyaryletherketone is 20 parts.

[0060] Comparative Example 2

[0061] A high-toughness epoxy resin material, which differs from Example 1 in that the amount of organosilicon core-shell particles is 5 parts.

[0062] Comparative Example 3

[0063] A high-toughness epoxy resin material, which differs from Example 2 in that the amount of polysulfone added is 40 parts.

[0064] Comparative Example 4

[0065] A high-toughness epoxy resin material differs from Example 3 in that step S2 involves adding 10 parts of organosilicon core-shell particles, 25 parts of resorcinol diglycidyl ether, and 25 parts of bisphenol F diglycidyl ether, and mechanically dispersing at high speed for 30 minutes to obtain mixed slurry B.

[0066] Comparative Example 5

[0067] A high-toughness epoxy resin material differs from Example 3 in that step S2 involves adding 5 parts of organosilicon core-shell particles, 5 parts of nano-silica, and 50 parts of resorcinol diglycidyl ether, followed by mechanical high-speed dispersion for 30 minutes to obtain mixed slurry B.

[0068] The preparation methods of the high-toughness epoxy resin materials in Comparative Examples 1-4 are the same as those in Example 1.

[0069] Performance testing

[0070] The epoxy resin materials provided in Examples 1-4 and Comparative Examples 1-4 of this application were subjected to the following performance tests:

[0071] Epoxy resin materials were cast in accordance with GB / T 2567-2021 "Test Methods for Performance of Resin Castings", and the tensile strength, elongation at break, flexural strength and impact toughness of the resin castings were tested.

[0072] Five samples were taken for each embodiment and comparative example, and the average value of the test results was taken. The specific test results are shown in Table 1.

[0073] Table 1 Performance Results

[0074] Implementation Example Tensile strength / MPa Elongation at break / % Bending strength / MPa <![CDATA[Impact toughness / kJ / m 2 > Example 1 89 4.02 160 24.8 Example 2 81 3.53 145 21.7 Example 3 83 3.76 143 20.1 Example 4 73 2.56 118 16.7 Comparative Example 1 65 3.61 121 21.3 Comparative Example 2 83 2.07 145 15.4 Comparative Example 3 58 1.32 100 10.6 Comparative Example 4 76 3.17 124 19.5 Comparative Example 5 63 1.95 118 11.6

[0075] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-toughness epoxy resin material, characterized in that, According to the weight parts, it includes: 40-60 parts of epoxy resin A, 20-30 parts of epoxy resin B, 20-40 parts of epoxy resin C, 25-30 parts of thermoplastic resin, 8-10 parts of toughening agent and 7-12 parts of curing agent. The total weight of epoxy resin A, epoxy resin B, and epoxy resin C is 100 parts. The viscosity of epoxy resin A is 300 mPa·s-900 mPa·s; The epoxy resin A is resorcinol diglycidyl ether; The toughening agent is an organosilicon core-shell particle; The epoxy resin B is one or a mixture of several of the following: triglycidyl p-aminophenol, triglycidyl m-aminophenol, and triglycidyl ether triphenylmethane. The epoxy resin C is one or a mixture of several of the following: bisphenol A diglycidyl ether, 4,5-epoxycyclohexane-1,2-dicarboxylic acid diglycidyl ester, and 1,2-cyclohexanedicarboxylic acid diglycidyl ester. The thermoplastic resin has a molecular weight ≤20000, and the thermoplastic resin is one or a mixture of several of polyethersulfone, polysulfone, polyphenylene ether, and polyaryletherketone. The preparation method of the high-toughness epoxy resin material includes the following steps: S1. Mix epoxy resin B with thermoplastic resin and stir at high temperature to obtain mixed component A; S2. The toughening agent is dispersed in epoxy resin A at room temperature to obtain mixed component B; S3, curing agent and epoxy resin C are stirred at room temperature and then ground by a three-roll mill to obtain mixed component C; S4. Cool down the mixed component A system, add mixed components B and C and stir to obtain a high-toughness epoxy resin matrix for winding prepreg; S5. Obtain epoxy resin material.

2. The high-toughness epoxy resin material according to claim 1, characterized in that, The curing agent is one of dicyandiamide, diaminodiphenyl sulfone, and diaminodiphenylmethane.

3. The high-toughness epoxy resin material according to claim 1, characterized in that, The epoxy resin material has a tensile strength ≥80MPa, an elongation at break ≥3.5%, and an impact strength ≥20kJ / m. 2 Flexural strength ≥130MPa.

4. The method for preparing a high-toughness epoxy resin material according to claim 1, characterized in that, The stirring temperature in step S1 is 110-130℃; The dispersion time in step S2 is 15-30 minutes; The stirring temperature in step S3 is 20-40℃.

5. The method for preparing a high-toughness epoxy resin material according to claim 1, characterized in that, The mixed component A system was cooled to 60-80℃.