Flame-retardant epoxy resin composite material, composition, preparation method and application

Abstract

The present invention belongs to the technical field of flame-retardant materials, and specifically relates to a flame-retardant epoxy resin composite material, a composition, a preparation method, and an application thereof. The present invention comprises the following steps: mixing VC@D, a base, and tromethamine, and performing treatment after the reaction to obtain the flame-retardant epoxy resin composite material; a method for preparing the VC@D comprises the following steps: mixing VC and DOPO, and performing treatment after the reaction to obtain VC@D; a method for preparing the VC comprises the following steps: mixing cyanuric chloride and vanillin, and performing reaction after the reaction to obtain VC; and a method for preparing the VC comprises the following steps: mixing cyanuric chloride and vanillin, and performing reaction after the reaction to obtain VC. The present invention has high flame retardancy while maintaining good mechanical properties.

Description

Technical Field

[0001] The present invention belongs to the technical field of flame retardant materials, and in particular relates to a flame retardant epoxy resin composite material, a composition, a preparation method and an application. Background Art

[0002] With the rapid development of electronic information, epoxy resin (EP) and its corresponding composite materials, the primary electronic packaging material, have become widely used in the industry. However, epoxy resin is flammable and releases large amounts of heat and smoke when burned, posing a significant risk to people's lives and property. To further expand the application of this material, technologies with flame retardant and reinforcement properties have gradually entered the public's field of vision and daily life, providing a better life.

[0003] Compounds containing P elements can effectively improve the flame retardant properties of polymer composites, especially phosphaphenanthrene (such as DOPO), which can improve the flame retardant properties of EP to a certain extent. However, its flame retardant efficiency is low, so it needs to be modified to synthesize an integrated (containing acid source, gas source and nitrogen source) intumescent flame retardant with both N elements and OH functional groups, which can effectively improve its flame retardant properties. However, the addition of flame retardants will reduce the mechanical properties of EP. It is necessary to find EP materials with high flame retardant ability that can meet the mechanical property requirements. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a flame retardant epoxy resin composite material, composition, preparation method and application, which has high flame retardancy while maintaining good mechanical properties.

[0005] The embodiment of the present invention provides a method for preparing a flame-retardant epoxy resin composite material, comprising the steps of mixing VC@D, a base, and tromethamine, and after the reaction is completed, treating the mixture to obtain the flame-retardant epoxy resin composite material;

[0006] The preparation method of VC@D is as follows: VC and DOPO are mixed, and after the reaction is completed, the mixture is treated to obtain VC@D;

[0007] The preparation method of VC comprises the following steps: mixing cyanuric chloride and vanillin, reacting them, and then treating them after the reaction is completed to obtain VC.

[0008] In one embodiment, in the method for preparing the flame-retardant epoxy resin composite material, the base is sodium hydroxide and the reaction solvent is dichloromethane.

[0009] In one embodiment, in the method for preparing the flame-retardant epoxy resin composite material, the reaction temperature is 50-70° C., and the treatment method is filtration and drying.

[0010] In one embodiment, in the preparation method of VC@D, the reaction solvent is 1,4-dioxane.

[0011] In one embodiment, in the preparation method of VC@D, the reaction temperature is 70-90° C., and the treatment method is cooling, filtering, and drying.

[0012] In one embodiment, carbonate is further added in the preparation method of VC.

[0013] In one embodiment, in the preparation method of VC, the reaction solvent is acetone, the reaction temperature is 50-60° C., and the treatment method is cooling, filtering, washing, and drying.

[0014] An embodiment of the present invention provides a flame-retardant epoxy resin composite material, which is prepared by using the preparation method.

[0015] An embodiment of the present invention provides a composition comprising the flame-retardant epoxy resin composite material, and preferably further comprising a thermosetting resin, polylactic acid, or polypropylene resin.

[0016] The embodiment of the present invention provides an application of the flame-retardant epoxy resin composite material, wherein the flame-retardant epoxy resin composite material is added to a polymer material to improve the flame retardancy. The polymer material is a thermosetting resin, polylactic acid, or polypropylene resin.

[0017] The present invention has the beneficial effect that the flame-retardant epoxy resin composite material can be applied to thermosetting resins such as epoxy resin, as well as polymer materials such as polylactic acid and polypropylene. The flame-retardant epoxy resin composite material of the present invention significantly improves the flame retardancy of the polymer while maintaining good mechanical properties of the retainer. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is the infrared spectrum of VC and vanillin.

[0019] Figure 2 Infrared spectra of VC, DOPO, and VC@D.

[0020] Figure 3 Infrared spectra of VC@D, Tris, and VC@D@T.

[0021] Figure 4 SEM (a) and EDS surface scan spectra of VC@D@T, where (a) is the SEM image; (b) is the overall EDS surface scan spectrum, (c) is the C spectrum, (d) is the N spectrum, (e) is the O spectrum, and (f) is the P spectrum.

[0022] Figure 5TGA curves of VC@D@T and DOPO. DETAILED DESCRIPTION

[0023] The present invention will be further described below with reference to the embodiments to facilitate understanding of the technical solutions of the present invention. However, this should not be construed as limiting the scope of the present invention to the following implementation cases.

[0024] Example 1

[0025] A method for preparing a flame-retardant epoxy resin composite material, comprising the following steps:

[0026] 1) Preparation of VC: Weigh 4.61 g of cyanuric chloride, 12.93 g of vanillin, and 9.01 g of anhydrous Na2CO3.

[0027] In a 100ml three-necked flask, add 40ml of acetone, vanillin, and anhydrous Na2CO3. After stirring for 1 hour, add cyanuric chloride and heat to 56°C for 8 hours. After cooling to room temperature, filter the product, wash three times with 80°C deionized water, and finally dry in a 60°C oven for 24 hours to obtain VC, a white powder. The reaction process is as follows.

[0028]

[0029] 2) Preparation of VC@D: Weigh 2.66 g VC and 4.32 g DOPO.

[0030] Add 20ml of 1,4-dioxane and DOPO to a 50ml three-necked flask and stir at room temperature until completely dissolved. Slowly add VC and heat to 80°C for 4 hours. Pour the solution into ice water, filter, and dry in a 60°C oven for 24 hours to obtain the white powder product VC@D. The reaction process is as follows.

[0031]

[0032] 3) Preparation of VC@D@T: Weigh 2.35 g VC@D, 0.72 g Tris, and 0.24 g NaOH.

[0033] In a 50ml three-necked flask, add 20ml of dichloromethane, VC@D, and NaOH. Stirring begins, and the temperature is raised to 60°C. Tris reagent is then slowly added. After reacting for 6 hours, the product is filtered and dried in a 60°C oven for 24 hours to obtain a yellow powder, VC@D@T. The reaction process is as follows.

[0034]

[0035] Example 2

[0036] Chemical structure of VC@D@T

[0037] The hydroxyl group (Ph-OH) on vanillin will react with cyanuric chloride to form the intermediate product VC. Figure 1 The infrared spectra of vanillin and VC were compared and it was found that the phenolic hydroxyl group (3391 cm -1 ) absorption peak disappears in the infrared spectrum of VC. In addition, the 1699 cm -1 The stretching vibration peak of CH=O at 37° has been detected, which indicates that the intermediate product VC is generated after the reaction of vanillin with cyanuric chloride.

[0038] In the reaction between VC and DOPO, the DOPO group replaces the aldehyde group in VC to generate the intermediate product VC@D ( Figure 2 ).according to Figure 2 The infrared spectra of VC and DOPO show that the spectrum of VC@D shows the pH of DOPO (2430 cm -1 ) and CH=O (1699 cm -1 ) disappears. In addition, due to the presence of -OH functional groups in the product VC@D, the newly generated 3248 cm -1 The peak at can be assigned to the stretching vibration of -OH, indicating that the reaction to generate VC@D was successful.

[0039] Figure 3 The infrared spectra of Tris and VC@D are shown. It can be seen that the trihydroxyl group in Tris (3349 cm -1 ) merged into a broader peak after the reaction, indicating that substitution had occurred. At the same time, other characteristic peaks of VC@D, including the 1572 cm -1 , 1371 cm of C=N bond -1 and 922 cm of the POC bond -1 , which remains basically unchanged. This shows that VC@D@T has been successfully synthesized.

[0040] Example 3

[0041] Microscopic morphology

[0042] As a basic means of characterizing material morphology, SEM can intuitively reflect the basic morphology and structure of the sample. Figure 4 (a) is a particle of VC@D@T. It can be seen from the figure that some particles on the surface of the particle are tightly bound to the particle, and the rest is relatively flat, indicating that the reactant has been introduced on the basis of the original product.

[0043] EDS can analyze the composition of samples by utilizing the different characteristic energies of X-ray photons of different elements. Figure 4(bf) is the distribution diagram of C, O, N, and P elements on the particles of VC@D@T with a particle size of 50 μm. It can be seen that the distribution positions of the four elements roughly overlap, and among them, C element is the most dense, followed by O, P, and N elements, indicating that the structure within the sample is relatively uniform and the number of elements is relatively reasonable.

[0044] Example 4

[0045] Thermogravimetric analysis

[0046] The thermal stability of VC@D@T and DOPO was determined by TGA in a nitrogen atmosphere. The experimental results are shown in Figure 5 As can be seen, the carbon residue rate of VC@D@T at 450°C is as high as 50.5%, which is much higher than the carbon residue rate of DOPO (0.23%). In the subsequent heating process, the carbon residue rate is also much higher than that of DOPO. These results show that VC@D@T modified with vanillin and Tris has better carbon-forming properties than unmodified DOPO. This is because its molecules contain benzene rings and triazine ring structures, which give it high thermal stability and good carbon-forming properties.

[0047] Example 5

[0048] Epoxy composite curing

[0049] Weigh a certain amount of E-44 epoxy resin into a three-necked flask and heat with stirring at 95°C until fluidized. Add 5wt% filler (VC@D@T and nano-calcium carbonate, weight ratio: 4:1) in batches and stir until uniform. Weigh a certain amount of DDM curing agent (E-44:DDM, weight ratio: 4.5:1) and add it in batches until completely dissolved. Quickly pour the mixture into a mold preheated at 90°C and let it sit for 3-5 minutes. Place the mold in a vacuum oven and evacuate for 10 minutes before heating. Cure at 120°C for 2 hours, 150°C for 2 hours, and 180°C for 1 hour before removing.

[0050] Comparative Example 1

[0051] Compared with Example 5, the difference is that only 5 wt% of nano calcium carbonate is used as the filler, and the rest remains unchanged.

[0052] Comparative Example 2

[0053] Compared with Example 5, the difference is that the filler is 5 wt% filler (the weight ratio of VC@D and nano-calcium carbonate is 4:1), and the rest remains unchanged.

[0054] Comparative Example 3

[0055] Compared with Example 5, the difference is that no filler is added and the rest remains unchanged.

[0056] Example 6

[0057] Flame retardant performance test: measured by cone calorimeter according to ISO 5660 test method.

[0058] The peak heat release of control group 3 (pure epoxy resin) is 1101kW / m 2 When 5wt% of nano calcium carbonate was added, the peak power (Comparative Example 1) dropped to 771 kW / m 2 When 5 wt% VC@D was added, the peak value of the comparative example 2 dropped to 693 kW / m 2 When 5 wt% of VC@D@T was added, the peak value (Example 1) further decreased to 642 kW / m 2 , and the peak area is the smallest, indicating that VC@D@T and nano-calcium carbonate have good flame retardant properties.

[0059] Example 7

[0060] Mechanical properties test: measured using a universal testing machine according to ISO 527-1 test method.

[0061] The tensile strength and elongation at break of Comparative Example 3 were 40.4 MPa and 4.86%, respectively;

[0062] When 5 wt% of nano-calcium carbonate was added, the tensile strength (Comparative Example 1) increased to 47.7 MPa, and the elongation at break decreased slightly;

[0063] When 5 wt% VC@D was added, its (Comparative Example 2) tensile strength and elongation at break decreased to 35.7 MPa and 3.86%;

[0064] After adding 5 wt% VC@D@T, although the tensile strength and elongation at break of Example 1 are lower than those of the pure resin, they increase to 39.5 MPa and 4.73% compared with those of Comparative Example 2, indicating that the combination of nano-calcium carbonate and VC@D@T has better mechanical properties.

[0065] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of protection of the present application is limited to these examples. In line with the present application, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of different aspects of one or more embodiments of the present application as described above, which are not provided in detail for the sake of simplicity.

[0066] The one or more embodiments of this application are intended to encompass all such substitutions, modifications, and variations that fall within the broad scope of this application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of one or more embodiments of this application should be included in the protection of this application.

Claims

1. A method for preparing a flame retardant epoxy resin composite material, characterized in that: VC@D, alkali and tromethamine are mixed, and after the reaction is completed, the mixture is treated to obtain a flame-retardant epoxy resin composite material; The preparation method of VC@D is as follows: VC and DOPO are mixed, and after the reaction is completed, the mixture is treated to obtain VC@D; The preparation method of VC comprises the following steps: mixing cyanuric chloride and vanillin, reacting them, and then treating them after the reaction is completed to obtain VC.

2. The preparation method according to claim 1, wherein In the preparation method of the flame-retardant epoxy resin composite material, the base is sodium hydroxide and the reaction solvent is dichloromethane.

3. The preparation method according to claim 1, wherein In the preparation method of the flame-retardant epoxy resin composite material, the reaction temperature is 50-70° C., and the treatment method is suction filtration and drying.

4. The preparation method according to any one of claims 1 to 3, wherein: In the preparation method of VC@D, the reaction solvent is 1,4-dioxane.

5. The preparation method according to any one of claims 1 to 3, wherein: In the preparation method of VC@D, the reaction temperature is 70-90° C., and the treatment method is cooling, filtering, and drying.

6. The preparation method according to any one of claims 1 to 3, wherein: In the preparation method of VC, carbonate is also added.

7. The preparation method according to any one of claims 1 to 3, wherein: In the preparation method of VC, the reaction solvent is acetone, the reaction temperature is 50-60° C., and the treatment method is to cool, filter, wash, and dry.

8. A flame retardant epoxy resin composite material, characterized in that: The product is prepared by the preparation method according to any one of claims 1 to 7.

9. A composition characterized in that: It comprises the flame-retardant epoxy resin composite material as claimed in claim 8.

10. An application of the flame-retardant epoxy resin composite material according to claim 8, characterized in that: The flame retardant epoxy resin composite material is used for adding into polymer materials to improve the flame retardant performance.

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