A bismaleimide resin modifier and a modified bismaleimide resin

Abstract

The present application belongs to the technical field of polymer materials, and particularly relates to a bismaleimide resin modifier and a modified bismaleimide resin. The present application provides a bismaleimide resin modifier. By using the modifier, a modified bismaleimide resin can be prepared, which is prepared from raw materials including the following components by weight: 1-100 parts of a maleimide compound, 1-100 parts of an allyl compound, and 1-50 parts of the modifier. The modified bismaleimide resin has excellent mechanical properties, especially tensile strength, which greatly expands the application of the bismaleimide resin in the fields of building, electronic materials, aerospace and other potential fields, and has good application prospect.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials technology, specifically relating to a bismaleimide resin modifier and a modified bismaleimide resin. Background Technology

[0002] Bismaleimide resin is a type of resin system derived from polyimide resin systems. It is one of the most promising high-temperature thermosetting resins currently available. Due to its excellent heat resistance, dielectric properties, and mechanical properties, it has been widely used as an advanced resin-based composite material in machinery, transportation, aerospace, and electronics fields. Bismaleimide monomers are molecules terminated by two maleimide functional groups, typically containing multiple aromatic groups. They exhibit high structural stability, are not easily decomposed, and do not crack or deform under high-temperature environments. Furthermore, bismaleimide resins possess good processing and molding properties, and can be prepared into sheets, tubes, rods, films, and other shapes using various processing methods to meet diverse engineering needs. Considerations of performance and cost place bismaleimide resins between epoxy resins and cyanate esters, potentially filling gaps that epoxy resins cannot fill. Their price is more competitive compared to lower-performance (bifunctional) cyanate esters. Therefore, bismaleimide resins have experienced rapid development and widespread application over the past two decades.

[0003] However, there is still room for improvement in the mechanical properties of bismaleimide resins. Modification is one feasible method to enhance these properties. Allyl compound modification of bismaleimide resins is currently the most mature and successful toughening approach. The resulting copolymer systems are characterized by stable prepolymers, good solubility and adhesion, and tough, heat-resistant, and humid heat-resistant cured products, along with good electrical and mechanical properties. Amine compound chain extension modification of bismaleimide resins, particularly diamine modification, is a relatively simple way to address the brittleness problem. Sulfur-containing compound modification of bismaleimide resins utilizes the mechanism of strong nucleophilic hydrogen sulfide compounds attacking the double bonds on the maleimide ring. The modified bismaleimide resins exhibit properties similar to thermoplastic elastomers, with extremely high elongation at break and excellent environmental resistance. Rubber-modified bismaleimide resin: The active groups of the rubber modifier react with the imide rings in the bismaleimide resin to form blocks. During the curing process, these rubber blocks precipitate from the matrix, forming a two-phase structure. The rubber phase induces the energy dissipation process of the matrix, improving the yield deformation capacity of the matrix to achieve the purpose of toughening.

[0004] Although there are various modifiers and modification methods for bismaleimide resins in the existing technology, in order to meet the diverse material requirements of various application fields and further expand the application scope of bismaleimide resins, how to improve the composition and structure of bismaleimide resins and further enhance their mechanical properties remains an important issue in this field. Summary of the Invention

[0005] To address the problems of the prior art, the present invention aims to provide a bismaleimide resin modifier and a modified bismaleimide resin.

[0006] A modified bismaleimide resin is made from raw materials comprising the following components in parts by weight:

[0007] Maleimide compounds 1-100 parts

[0008] 1-100 parts of allyl compounds

[0009] Modifier 1-50 parts;

[0010] The modifier contains at least two molecules. Compounds with a specific structure.

[0011] Preferably, the modifier is selected from the following compounds, or salts thereof, or stereoisomers thereof, or solvates thereof:

[0012]

[0013]

[0014] Preferably, it is made from raw materials comprising the following components in parts by weight:

[0015] 52 samples of maleimide compounds

[0016] 39 allyl compounds

[0017] 10.11 parts modifier.

[0018] Preferably, the maleimide compound is selected from at least one of bismaleimide diphenylmethane, bismaleimide diphenyl ether, (1,4-phenylene)bismaleimide, or m-phenylene bismaleimide;

[0019] And / or, the allyl compound is selected from at least one of diallyl bisphenol A or diallyl bisphenol S.

[0020] The present invention also provides a method for preparing the above-mentioned modified bismaleimide resin, comprising the following steps:

[0021] Step 1: Mix the allyl compound and the modifier evenly under heating conditions to obtain mixture A;

[0022] Step 2: Slowly add maleimide compounds to mixture A, and mix thoroughly to obtain liquid mixture B;

[0023] Step 3: Add liquid mixture B to the mold and let it solidify to obtain the final product.

[0024] Preferably, in step 1, the mixing temperature is 60℃-100℃;

[0025] And / or, in step 2, the mixing temperature is 130℃-150℃;

[0026] And / or, in step 3, the curing conditions are: curing at 150℃-180℃ for 3h-5h, and then curing at 220℃-250℃ for 6h-10h.

[0027] The present invention also provides the use of the above-described modified bismaleimide resin in the preparation of aerospace equipment, electronic materials, adhesives or coatings.

[0028] This invention also provides compounds of Formula I, or salts thereof, or stereoisomers thereof, or solvates thereof:

[0029]

[0030] The present invention also provides a method for preparing the above-mentioned compound, comprising the following steps:

[0031] Step 1: react p-hydroxybenzaldehyde with cyanuric chloride to obtain 2,4,6-tris(4-aldehydephenoxy)-1,3,5-triazine;

[0032]

[0033] Step 2: 2,4,6-tris(4-aldehydephenoxy)-1,3,5-triazine is reacted with allyltriphenylphosphonium bromide to give 2,4,6-tris(4-butadienylphenoxy)-1,3,5-triazine;

[0034] .

[0035] Preferably, in step 1, the reaction solvent is selected from at least one of dichloromethane, acetone, and tetrahydrofuran;

[0036] And / or, in step 1, the reaction is carried out in the presence of a base, wherein the base is selected from at least one of triethylamine, potassium carbonate, and sodium hydroxide;

[0037] And / or, in step 1, the reaction temperature is 30-60℃;

[0038] And / or, in step 2, the reaction solvent is selected from at least one of dichloromethane and tetrahydrofuran;

[0039] And / or, in step 2, the reaction is carried out in the presence of a base, wherein the base is selected from at least one of potassium tert-butoxide, butyllithium, and sodium methoxide;

[0040] And / or, in step 2, the reaction temperature is 20-40℃.

[0041] This invention provides a novel modifier for modifying bismaleimide resins. The modifier contains at least two conjugated diene structures linked to a benzene ring. Using this modifier, modified bismaleimide resins with excellent mechanical properties (especially tensile strength) can be produced. This greatly expands the applications of bismaleimide resins in construction, electronic materials, aerospace, and other potential fields, showing great promise for future applications.

[0042] Obviously, based on the above description of the present invention, and according to common technical knowledge and conventional methods in the field, various other modifications, substitutions, or alterations can be made without departing from the basic technical concept of the present invention.

[0043] The following detailed embodiments further illustrate the above-described content of the present invention. However, this should not be construed as limiting the scope of the present invention to the following examples. All technologies implemented based on the above-described content of the present invention fall within the scope of the present invention. Attached Figure Description

[0044] Figure 1 The 2,4,6-tris(4-aldehydephenoxy)-1,3,5-triazine and 2,4,6-tris(4-butadienylphenoxy)-1,3,5-triazine prepared in Example 1 1 H NMR results;

[0045] Figure 2 The DSC curves for manual mixing of BDM and TBPT at a 1:1 ratio, the BD curing process, and the BD / TBPT-5 curing process in Experiment Example 1 are shown.

[0046] Figure 3 The tensile strength, tensile modulus, elongation at break, and impact strength of the modified bismaleimide resin in Experiment Example 2 are characterization results. Detailed Implementation

[0047] Unless otherwise specified, all reagents and materials used in the following examples and experimental cases are commercially available products.

[0048] Example 1: Bismaleimide Resin Modifier

[0049] This embodiment provides a bismaleimide resin modifier: 2,4,6-tris(4-butadienylphenoxy)-1,3,5-triazine (TBPT), whose structural formula is as follows:

[0050]

[0051] Its preparation method is as follows:

[0052]

[0053] Synthesis of 1,4,6-tris(4-aldehydephenoxy)-1,3,5-triazine

[0054] 0.1 mol of p-hydroxybenzaldehyde was completely dispersed in 200 mL of tetrahydrofuran under nitrogen flow. At room temperature, 0.1 mol of triethylamine and 0.03 mol of cyanuric chloride were added separately to the above system. The entire system was then reacted overnight at 50 °C. The mixture was filtered, and the solvent was evaporated to obtain the white target product.

[0055] 2. Synthesis of 2,4,6-tris(4-butadienylphenoxy)-1,3,5-triazine

[0056] 0.1 mol of allyltriphenylphosphonium bromide was completely dispersed in 300 mL of tetrahydrofuran under nitrogen flow. Then, 0.1 mol of potassium tert-butoxide was added to the system at 0 °C, and the reaction was allowed to proceed for 30 minutes. Finally, 0.03 mol of 2,4,6-tris(4-aldehydephenoxy)-1,3,5-triazine was added to the system at 0 °C, and the mixture was heated to 25 °C and reacted for another 12 hours, yielding 2,4,6-tris(4-butadienylphenoxy)-1,3,5-triazine after purification.

[0057] 2,4,6-Tris(4-aldehydephenoxy)-1,3,5-triazine and 2,4,6-tris(4-butadienylphenoxy)-1,3,5-triazine 1 The H NMR results are as follows Figure 1 As shown. 1 H NMR results (400MHz, DMSO)δ

[0058] (7.42-7.734H), δ6.90(1H), δ6.51(1H), δ6.32(1H), δ5.30-5.50(2H)). The positions and amounts of characteristic hydrogen atoms correspond to theoretical values, and the purity is high. This indicates the successful synthesis of 2,4,6-tris(4-aldehydephenoxy)-1,3,5-triazine and 2,4,6-tris(4-butadienylphenoxy)-1,3,5-triazine (TBPT).

[0059] Example 2 Modified bismaleimide resin

[0060] In this embodiment, a series of modified bismaleimide resins (BD / TBPT resins) were prepared according to the mass ratio, and the specific formulations are shown in Table 1.

[0061] Table 1 Specific Formulation of BD / TBPT Resin Matrix

[0062]

[0063]

[0064] Taking BD / TBPT-10 as an example, the preparation process of different resin matrices is illustrated as follows: First, 39g of DBA and 10.11g of TBPT (prepared according to the method of Example 1) were thoroughly mixed at 80°C. Then, the mixture was heated to 140°C, and 52g of BDM powder was slowly added. After 30 minutes, the resulting clear and transparent liquid was evacuated for another 30 minutes to completely remove the gas. Subsequently, the liquid was immediately poured into a preheated polytetrafluoroethylene mold for curing. The curing process was as follows: 2 hours at 150°C, 2 hours at 180°C, 4 hours at 220°C, and 4 hours at 250°C. After the above operations, BD / TBPT-10 was obtained.

[0065] The technical solution of the present invention will be further illustrated by the following experiment. The samples used in the experiment were prepared according to the method of Example 2.

[0066] Experimental Example 1: Effect of TBPT on the Curing Process of Bismaleimide Resin

[0067] I. Experimental Methods

[0068] The exothermic reaction during the curing process of bismaleimide resin was measured using a differential scanning calorimeter to determine the curing process.

[0069] II. Experimental Results

[0070] like Figure 2As shown, the DSC curve of manually mixed BDM and TBPT at a 1:1 ratio exhibits three peaks: the first endothermic peak is the melting peak of BDM powder, the second exothermic peak is the reaction exothermic peak of BDM and TBPT, and the third peak is the exothermic peak of BDM self-polymerization. Compared with the BD prepolymer, the DSC curve of the BD / TBPT-5 prepolymer shows a smaller exothermic peak at 150℃, which belongs to the reaction exothermic peak of BDM and TBPT. The onset temperature of this peak is significantly lower than that of the reaction exothermic peak of BDM and DBA. The lower the temperature of the DSC exothermic peak, the higher the macroscopic reactivity of the system. Macroscopic reactivity is jointly controlled by the concentration of reactive centers, the reactivity of functional groups, and the chain segment diffusion rate. If the concentration of reactive centers is kept constant and the chain segment diffusion rate is not considered, the macroscopic reactivity can reflect the reactivity of functional groups. Therefore, the above DSC results indicate that the reactivity of TBPT with BDM is higher than that with DBA.

[0071] In addition, the curing temperature of the system at different heating rates was measured using the experimental data mentioned above, and the curing temperature at which the heating rate was zero was obtained by extrapolation, thereby determining the optimal curing temperature range of BD / TBPT resin.

[0072] Experimental Example 2: Effect of 2,4,6-tris(4-butadienylphenoxy)-1,3,5-triazine on the mechanical properties of bismaleimide resin

[0073] I. Experimental Methods

[0074] The tensile strength and tensile modulus of bismaleimide resin were measured using a universal tensile testing machine; the impact strength of bismaleimide resin was measured using an impact testing machine in a simply supported beam configuration.

[0075] II. Experimental Results

[0076] like Figure 3 As shown, the tensile strength of bismaleimide resins increases with increasing TBPT content. Specifically, BD / TBPT-10 achieves a tensile strength of 100 MPa, a 49% increase compared to BD's 67 MPa. Furthermore, tensile modulus, elongation at break, and impact strength are also significantly improved.

[0077] The above experimental results show that the addition of TBPT can effectively improve the tensile strength, tensile modulus, elongation at break and impact strength of bismaleimide resin, thus obtaining a modified bismaleimide resin with improved mechanical properties.

[0078] The amount of TBPT added has a significant impact on the properties of modified bismaleimide resin. On the other hand, the amount of TBPT added affects the molding process properties of BD / TBPT resin. With increasing TBPT content, the viscosity of the system increases during prepolymerization, making the molding process of the cast body more complex. Therefore, the BD / TBPT-10 system is the optimal formulation considering both mechanical properties and molding process properties.

[0079] In summary, this invention provides a novel modifier for modifying bismaleimide resins. Using this modifier, modified bismaleimide resins with excellent mechanical properties (especially tensile strength) can be produced. Therefore, this invention has excellent application prospects.

Claims

1. A modified bismaleimide resin, characterized in that, It is made from raw materials comprising the following components in parts by weight: Maleimide compounds 1-100 parts 1-100 parts of allyl compounds Modifier 1-50 parts; The modifier is .

2. The modified bismaleimide resin according to claim 1, characterized in that, It is made from raw materials comprising the following components in parts by weight: 52 samples of maleimide compounds 39 allyl compounds Modifier 10.11 parts.

3. The modified bismaleimide resin according to claim 1, characterized in that: The maleimide compound is selected from at least one of bismaleimide diphenylmethane, bismaleimide diphenyl ether, (1,4-phenylene) bismaleimide or m-phenylene bismaleimide; And / or, the allyl compound is selected from at least one of diallyl bisphenol A or diallyl bisphenol S.

4. The method for preparing the modified bismaleimide resin according to any one of claims 1-3, characterized in that, The steps include the following: Step 1: Mix the allyl compound and the modifier evenly under heating conditions to obtain mixture A; Step 2: Slowly add maleimide compounds to mixture A, and mix thoroughly to obtain liquid mixture B; Step 3: Add liquid mixture B to the mold and let it solidify to obtain the final product.

5. The preparation method according to claim 4, characterized in that: In step 1, the mixing temperature is 60℃-100℃; And / or, in step 2, the mixing temperature is 130℃-150℃; And / or, in step 3, the curing conditions are: curing at 150℃-180℃ for 3h-5h, and then curing at 220℃-250℃ for 6h-10h.

6. The use of the modified bismaleimide resin according to any one of claims 1-3 in the aerospace machinery, electronics industry, resin matrix of advanced composite materials, high-temperature insulating materials, adhesives or coatings.

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