Polyether amine bismaleimide and synthesis and application thereof

Abstract

The invention discloses polyether amine bismaleimide as well as synthesis and application thereof. The polyether amine bismaleimide is a reactant of polyether amine and maleic anhydride, the melting point temperature of the polyether amine bismaleimide is-20-5 DEG C, the polyether amine bismaleimide is transparent liquid at normal temperature, the viscosity of bismaleimide resin can be effectively reduced, and the manufacturability of the bismaleimide resin can be improved. Blended resin prepared from polyether amine bismaleimide and BD resin is suitable for being used as a high-performance composite material resin matrix, and the obtained composite material resin matrix has application value in the fields of military industry, aerospace, electronics and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of bismaleimide synthesis and application, and specifically relates to polyetheramine bismaleimide and a synthesis method and application thereof. Background Art

[0002] Bismaleimide (BMI for short) is a type of bifunctional compound with maleimide as the active end group, which can be blended and copolymerized with a variety of unsaturated monomers to obtain thermosetting resin materials. Common allyl unsaturated monomers include diallyl bisphenol A (DABPA). Bismaleimide resin is widely used in military, aerospace, electronics and other fields due to its excellent high temperature resistance, moisture and heat resistance, insulation and flame retardancy.

[0003] The principle of BMI synthesis is to react diamine with two times the mole of maleic anhydride through cyclodehydration. The most advanced method for synthesizing BMI is azeotropic distillation dehydration, that is, toluene or xylene is used as solvent and high boiling point polar solvents such as N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc) are added, benzenesulfonic acid or p-toluenesulfonic acid is used as dehydrating agent, and azeotropic distillation dehydration is used to synthesize BMI monomer. The synthesis reaction process is all homogeneous, and the obtained product has high yield and stable product quality.

[0004] At present, the main commercial BMI monomers in China are diphenylmethane bismaleimide BDM. BDM has the largest usage and the widest application due to its easy availability of raw materials, low cost, and excellent comprehensive performance. However, BDM has problems such as high melting point and poor processability. Therefore, the BMI monomer category in the field of bismaleimide resin in China is single, which is difficult to meet the application needs brought about by scientific and technological progress. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art and provide a synthesis and application of polyetheramine bismaleimide. The polyetheramine bismaleimide is a long-chain structure containing a flexible group and is liquid at room temperature. It can effectively reduce the viscosity of bismaleimide resin and improve its process performance.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A polyetheramine bismaleimide, the structure of which is shown in the following formula (2):

[0008]

[0009] Among them, n 2 is 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10.

[0010] According to an embodiment of the present invention, the melting point of the polyetheramine bismaleimide represented by formula (2) is -20 to 5°C.

[0011] According to an embodiment of the present invention, the polyetheramine bismaleimide represented by formula (2) is in liquid state at room temperature (0-30° C.).

[0012] The present invention also provides a method for preparing the polyetheramine bismaleimide as shown in the above formula (2), comprising the following steps:

[0013] The polyetheramine represented by formula (1) is reacted with maleic anhydride.

[0014]

[0015] Among them, n 1 Same as n 2 , is 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10.

[0016] According to an embodiment of the present invention, the polyetheramine bismaleimide shown in formula (2) is prepared by the following method:

[0017] (1) maleic anhydride is added to a solvent, the polyetheramine represented by formula (1) is prepared into a solution, and the solution is added dropwise to the maleic anhydride solution, and the dropping speed is controlled so that the solution temperature does not exceed 30° C.;

[0018] (2) After the dropwise addition is completed, the reaction solution is stirred at 0-30°C for 1-12 hours;

[0019] (3) adding a dehydrating agent to perform azeotropic distillation until no more water is distilled out and cooling to room temperature;

[0020] (4) The reaction solution is subjected to rotary evaporation and extraction purification to obtain the polyetheramine bismaleimide represented by formula (2).

[0021] According to an embodiment of the present invention, the dehydrating agent is selected from one or both of benzenesulfonic acid and p-toluenesulfonic acid.

[0022] According to an embodiment of the present invention, the solvent is selected from a mixed solvent consisting of one of toluene and xylene, and one of N,N-dimethylformamide (DMF) and N,N-dimethylacetamide (DMAc).

[0023] According to an embodiment of the present invention, the extractant used for extraction is selected from a mixed solvent of one of butanone, ethyl acetate, toluene, chloroform, and dichloromethane and deionized water.

[0024] According to an embodiment of the present invention, the molar ratio of the polyetheramine represented by formula (1) to maleic anhydride is 1:1.0 to 8.0, for example, 1:1.0 to 5.0.

[0025] According to an embodiment of the present invention, the molar ratio of the polyetheramine represented by formula (1) to the dehydrating agent is 1:0.2 to 1.0, for example, 1:0.5 to 0.8.

[0026] According to an embodiment of the present invention, the concentration of the polyetheramine solution represented by formula (1) is a mass percentage selected from 10 to 30%, such as 15 to 25%.

[0027] According to an embodiment of the present invention, the solid content of the reaction solution is a mass percentage selected from 5 to 20%, such as 10 to 15%.

[0028] According to an embodiment of the present invention, the dropping speed of the polyetheramine solution represented by formula (1) is 1 to 10 mL / min, for example, 1.5 to 5 mL / min.

[0029] According to an embodiment of the present invention, the azeotropic distillation temperature is 80-130°C.

[0030] According to an embodiment of the present invention, the water separation time in step (3) is 3 to 8 hours.

[0031] According to an embodiment of the present invention, the rotary evaporation temperature during the purification process is 50-120°C, such as 80-100°C.

[0032] The present invention also provides a blended resin, denoted as BD-PEABMI, which is a blended resin of the above-mentioned polyetheramine bismaleimide, diphenylmethane bismaleimide (BDM) and diallyl bisphenol A (DABPA).

[0033] The present invention also provides a method for preparing the blended resin BD-PEABMI as described above, comprising the following steps:

[0034] DABPA and BDM react at high temperature, and the temperature is lowered to obtain BD resin; the BD resin is heated until it is melted, and then the polyetheramine bismaleimide represented by formula (2) is added and stirred until the resin is homogeneous and transparent.

[0035] According to an embodiment of the present invention, the polyetheramine bismaleimide represented by formula (2) used in the process of preparing the blended resin BD-PEABMI is a mixture of at least two of a monomer, a dimer and a multimer.

[0036] According to an embodiment of the present invention, the blended resin BD-PEABMI is prepared by the following method:

[0037] DABPA is stirred at high temperature and heated to 80-150°C, BDM is added, stirred until homogeneous and transparent, cooled and discharged to obtain BD resin; BD resin is heated until melted, polyetheramine bismaleimide represented by formula (2) is added at 80-150°C, stirred until the resin is homogeneous and transparent, cooled and discharged to obtain BD-PEABMI, a blended resin of polyetheramine bismaleimide and BD resin.

[0038] According to an embodiment of the present invention, the molar ratio of DABPA to BDM is 1:0.5-5, for example, 1:1-1.5.

[0039] According to an embodiment of the present invention, the mass ratio of the polyetheramine bismaleimide represented by formula (2) to the BD resin is 1-100wt%:1, for example, 1-10wt%:1, such as 2.5wt%:1 or 5wt%:1.

[0040] According to an embodiment of the present invention, the melting temperature of the DABPA and bismaleimide (BDM) is 120-150°C.

[0041] According to an embodiment of the present invention, the melting temperature of the polyetheramine bismaleimide represented by formula (2) and the BD resin is 120-130°C.

[0042] The present invention also provides a blended resin BD-PEABMI prepared by the method described above.

[0043] According to an embodiment of the present invention, the BD-PEABMI resin is homogeneous and transparent at room temperature (0-30° C.).

[0044] The present invention also provides the use of the above-mentioned blended resin BD-PEABMI as a composite resin matrix in the fields of military industry, aerospace, electronics, etc., such as cable covers, wings and PCB substrates.

[0045] The present invention also provides a cured product of the blended resin BD-PEABMI.

[0046] The present invention also provides a method for preparing the solidified product, which is obtained by degassing the blended resin BD-PEABMI as described above and then curing and heating it.

[0047] According to an embodiment of the present invention, the degassing is performed at 80-150°C.

[0048] According to an embodiment of the present invention, the curing temperature rising process is: 180°C / 2h, 200°C / 2h, 220°C / 2h, 250°C / 5h.

[0049] The beneficial effects of the present invention are:

[0050] The invention discloses a synthesis method and application of polyetheramine bismaleimide. The obtained polyetheramine bismaleimide is liquid at room temperature and has a melting point of -20 to 5°C. Melting it with bismaleimide resin can effectively reduce the viscosity of the bismaleimide resin and improve its processability. The polyetheramine bismaleimide of the invention can be melt-mixed with traditional BD resin in any proportion, and the obtained blended resin is homogeneous and transparent. The polyetheramine bismaleimide greatly improves the process performance of the resin, and the obtained mixed resin is suitable as a high-performance composite material resin matrix. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 The viscosity of the resin obtained in Comparative Example 1 and Examples 4-5 changes with time. DETAILED DESCRIPTION

[0052] The present invention will be further described below in conjunction with specific embodiments, but the present invention is not limited to the following embodiments.

[0053] The viscosity test method in the following embodiment is: the viscosity of the resin is tested at different temperatures by rheometer method, and the heating rate is 4°C / min.

[0054] Example 1

[0055] Add 27.45g maleic anhydride, 20ml DMAc and 220mL toluene to a three-necked flask equipped with a stirrer, a thermometer and a reflux condenser, and stir evenly. Take 14.29g polyetheramine oligomer (number average molecular weight is 190), 30ml DMAc and 30mL toluene to make a solution, add it dropwise to the maleic anhydride solution, and control the drop rate to 3mL / min; after the dropwise addition is completed, react at 25°C for 3h. Add 5.33g p-toluenesulfonic acid to the above system, heat to about 110°C, the solution becomes a light yellow transparent solution, continue to heat to boiling and separate water, observe the reflux and water separation conditions, no water will be separated after 5h of water separation reaction, and cool down. The reaction solution is evaporated at 95°C to remove the solvent, and dichloromethane and deionized water are added to extract and purify to obtain polyetheramine bismaleimide, which is a transparent liquid at room temperature.

[0056] Example 2

[0057] Add 25.43g maleic anhydride, 22mL DMAc and 210mL xylene to a three-necked flask equipped with a stirrer, a thermometer and a reflux condenser, and stir evenly. Take 19.34g polyetheramine oligomer (number average molecular weight is 248), 45mL DMAc and 30mL xylene to make a solution, add it dropwise to the maleic anhydride solution, and control the drop rate to 2.3mL / min; after the dropwise addition is completed, react at 25°C for 4h. Add 7.98g p-toluenesulfonic acid to the above system, heat to about 110°C, the solution becomes a light yellow transparent solution, continue to heat to boiling and separate water, observe the reflux and water separation conditions, no water will be separated after 6h of water separation reaction, and cool down. The reaction solution is evaporated at 100°C to remove the solvent, and dichloromethane and deionized water are added to extract and purify to obtain polyetheramine bismaleimide, which is a transparent liquid at room temperature.

[0058] Example 3

[0059] Add 26.67g of maleic anhydride, 25mL of DMF and 220mL of toluene to a three-necked flask equipped with a stirrer, a thermometer and a reflux condenser, and stir evenly. Take 24.4g of polyetheramine oligomer (number average molecular weight of 306), 50mL of DMF and 40mL of toluene to make a solution, add it dropwise to the maleic anhydride solution, and control the drop rate to 1.8mL / min; after the dropwise addition is completed, react at 25°C for 5.8h. Add 8.65g of p-toluenesulfonic acid to the above system, heat to about 112°C, the solution becomes a light yellow transparent solution, continue to heat to boiling and separate water, observe the reflux and water separation conditions, no water will be separated after 7h of water separation reaction, and cool down. The reaction solution is evaporated at 90°C to remove the solvent, and dichloromethane and deionized water are added to extract and purify to obtain polyetheramine bismaleimide, which is a transparent liquid at room temperature.

[0060] Comparative Example 1

[0061] Add 1.5 mol of diallyl bisphenol A to a three-necked flask equipped with a stirrer and a thermometer, and add 1.5 mol of BDM when the temperature rises to 120°C. The melting temperature should not exceed 120°C. Stir until the phase is homogeneous and transparent, and cool and discharge to obtain BD resin.

[0062] Example 4

[0063] In a three-necked flask equipped with a stirrer and a thermometer, 100 g of the BD resin obtained in the above comparative example 1 was added, and when the temperature was raised to 130° C., 2.5 g of the polyetheramine bismaleimide prepared in Example 2 was added, and the melting temperature did not exceed 130° C. The mixture was stirred until homogeneous and transparent, and the temperature was lowered and the material was discharged to obtain a homogeneous and transparent BD-PEABMI-2.5wt% resin.

[0064] Example 5

[0065] In a three-necked flask equipped with a stirrer and a thermometer, 100 g of the BD resin obtained in the above comparative example 1 was added, and when the temperature was heated to 130° C., 5.0 g of the polyetheramine bismaleimide prepared in Example 2 was added, and the melting temperature did not exceed 130° C. The mixture was stirred until homogeneous and transparent, and the temperature was lowered and the material was discharged to obtain a homogeneous and transparent BD-PEABMI-5wt% resin.

[0066] Example 6

[0067] In a three-necked flask equipped with a stirrer and a thermometer, 100 g of the BD resin obtained in the above comparative example 1 was added, and when the temperature was heated to 130° C., 10 g of the polyetheramine bismaleimide prepared in Example 2 was added, and the melting temperature did not exceed 130° C. The mixture was stirred until homogeneous and transparent, and the temperature was lowered and the material was discharged to obtain a homogeneous and transparent BD-PEABMI-10wt% resin.

[0068] Example 7

[0069] The differences between the bismaleimide resins obtained in the above-mentioned comparative example 1 and examples 4-6 are as follows: the resin obtained in comparative example 1 is a BD resin; the resin obtained in example 4 is a blended resin obtained by adding 2.5 wt% of polyetheramine bismaleimide to BD resin; the resin obtained in example 5 is a blended resin obtained by adding 5.0 wt% of polyetheramine bismaleimide to BD resin; the resin obtained in example 6 is a blended resin obtained by adding 10 wt% of polyetheramine bismaleimide to BD resin. The purpose is to compare the viscosity-reducing effect of polyetheramine bismaleimide in BD resin. The viscosity-temperature curves of the three resins prepared in comparative example 1 and examples 4-5 were plotted under heating conditions (4°C / min), and the curve comparison diagram is shown in the attached figure. Figure 1 .from Figure 1 It can be clearly seen that polyetheramine bismaleimide can effectively reduce the viscosity of BD resin, and the greater the amount added, the greater the decrease in resin viscosity.

[0070] Example 7

[0071] The resins obtained in Comparative Example 1 and Examples 4 to 6 were placed in a vacuum drying oven, degassed at 120°C for 10 minutes, and then placed in a programmed temperature oven for curing to obtain respective cured resins. The curing temperature rise process was specifically: 180°C / 2h, 200°C / 2h, 220°C / 2h, 250°C / 5h. The heat resistance and mechanical properties of the resins were tested.

[0072] The above-mentioned cured resin was subjected to the following performance tests:

[0073] The flexural strength and flexural modulus are tested by a universal tensile machine according to the test standard GB / T 2567-2008.

[0074] The impact strength is tested using a simply supported beam impact machine in accordance with the test standard GB / T 2567-2008.

[0075] 5% thermal decomposition temperature (T 5％ ) was tested using a thermal analyzer with a heating rate of 10°C / min and a nitrogen protective gas flow rate of 50 mL / min.

[0076] The glass transition temperature (Tg) was tested using a dynamic mechanical thermal analyzer with a test frequency of 1 Hz and a heating rate of 5 °C / min.

[0077] Table 1 Performance test results of the cured resins of Comparative Example 1 and Examples 4-6

[0078]

[0079] As described above, the present invention can safely and easily prepare polyetheramine bismaleimide, which has a melting point of -20 to 5°C and is liquid at room temperature. Mixing it with bismaleimide resin can effectively reduce the viscosity of the bismaleimide resin and improve its processability. As can be seen from Table 1, after adding polyetheramine bismaleimide, the heat resistance, bending strength and impact strength of the resin are improved. It can be seen that polyetheramine bismaleimide is a very excellent bismaleimide resin additive. The mixed resin prepared by introducing it has excellent processability, heat resistance and mechanical properties, and is suitable as a high-performance composite material resin matrix.

[0080] The above is an explanation of the embodiments of the present invention. However, the present invention is not limited to the above embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A polyetheramine bismaleimide, the structure of which is shown in the following formula (2): in, n 2 is 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10.

2. The polyetheramine bismaleimide according to claim 1, It is characterized in that Melting point is -20~5℃; Preferably, it is liquid at room temperature (0-30°C).

3. A method for preparing the polyetheramine bismaleimide according to claim 1 or 2, It is characterized in that The steps include: The polyetheramine represented by formula (1) is reacted with maleic anhydride. Among them, n 1 is 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10.

4. The preparation method according to claim 3, It is characterized in that The steps include: (1) maleic anhydride is added to a solvent, the polyetheramine represented by formula (1) is prepared into a solution, and the solution is added dropwise to the maleic anhydride solution, and the dropping speed is controlled so that the solution temperature does not exceed 30° C.; (2) After the dropwise addition is completed, the reaction solution is stirred at 0-30°C for 1-12 hours; (3) adding a dehydrating agent to perform azeotropic distillation until no more water is distilled out and cooling to room temperature; (4) The reaction solution is subjected to rotary evaporation and extraction purification to obtain the polyetheramine bismaleimide represented by formula (2).

5. A blended resin, denoted as BD-PEABMI, which is a blended resin of the polyetheramine bismaleimide according to claim 1 or 2, diphenylmethane bismaleimide (BDM) and diallyl bisphenol A (DABPA).

6. The method for preparing the blended resin according to claim 5, It is characterized in that The following steps are involved: DABPA and BDM react at high temperature, and the temperature is lowered to obtain BD resin; the BD resin is heated until it is melted, and then the polyetheramine bismaleimide according to claim 1 or 2 is added, and stirred until the resin is homogeneous and transparent.

7. The preparation method according to claim 6, It is characterized in that The polyetheramine bismaleimide used in the process of preparing the blended resin BD-PEABMI is a mixture of at least two of a monomer, a dimer and a multimer.

8. The preparation method according to claim 6 or 7, It is characterized in that The blended resin BD-PEABMI is prepared by the following method: DABPA is heated to 80-150°C under high temperature with stirring, BDM is added, stirred until homogeneous and transparent, cooled and discharged to obtain BD resin; BD resin is heated to melt, polyetheramine bismaleimide is added at 80-150°C, stirred until the resin is homogeneous and transparent, cooled and discharged to obtain BD-PEABMI, a blended resin of polyetheramine bismaleimide and BD resin; Preferably, the molar ratio of DABPA to BDM is 1:0.5-5; Preferably, the mass ratio of the polyetheramine bismaleimide represented by formula (2) to the BD resin is 1 to 100 wt%:1; Preferably, the melting temperature of DABPA and bismaleimide (BDM) is 120-150° C.; Preferably, the melting temperature of polyetheramine bismaleimide and BD resin is 120-130°C.

9. Use of the blended resin according to claim 5 as a composite resin matrix in the fields of military industry, aerospace, electronics, etc., such as cable covers, wings and PCB substrates. 10 . A cured resin, which is a cured product of the blended resin according to claim 5 .

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