A method for preparing functionalized oligomeric PPO-modified phthalonitrile resin
By blending and copolymerizing functionalized low molecular weight PPO with phthalonitrile resin, the problems of high dielectric properties and high brittleness of phthalonitrile resin are solved, low curing temperature and high dielectric properties are improved, and production costs are reduced.
Patent Information
- Application Number
- CN202310411329.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-04-18
- Publication Date
- 2025-09-16
- Estimated Expiration
- 2043-04-18
AI Technical Summary
Phthalonitrile resin has high dielectric properties and is very brittle, has a high curing temperature and a long curing time, making it difficult to apply on a large scale; PPO has a high molecular weight and poor fluidity, making it difficult to process.
Functionalized low molecular weight PPO is blended and copolymerized with phthalonitrile resin, and dissolved by ultrasound, heating or stirring to prepare functionalized oligomeric PPO modified phthalonitrile resin, thereby reducing the curing temperature and improving the dielectric properties.
It effectively reduces the curing temperature and dielectric loss of phthalonitrile resin, improves toughness, maintains high heat resistance, reduces production costs, and improves dielectric properties and flame retardancy.
Smart Images
Figure CN116606548B_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of thermosetting resins and composite materials thereof, and specifically relates to a preparation method of a functionalized oligomeric PPO modified phthalonitrile resin. Background Art
[0002] With the rapid development of science and technology, the demand for various electronic devices and equipment has increased dramatically, and the dielectric properties of resin matrix have attracted much attention, especially in the field of PCB boards. As a high-performance thermosetting resin, phthalonitrile resin has an excellent heat resistance, which has attracted more and more attention in the electronics industry. In addition, it also has good mechanical properties, moisture resistance, chemical resistance, radiation resistance, flame retardancy and self-extinguishing, outstanding optical properties and electrical properties, and high glass transition temperature. It can be used as a resin matrix with extreme service performance composite materials, and has broad application prospects in high-tech fields such as aerospace, automobiles, and machinery. Although phthalonitrile dielectric properties have certain advantages over other resins, its dielectric constant and dielectric loss are higher, and it is necessary to improve its dielectric properties by molecular design or other methods. In addition, phthalonitrile resin is relatively brittle, has a high curing temperature, and a long curing time, and faces some difficulties in the process of actual application.
[0003] Polyphenylene ether (PPO) is a thermoplastic material with high glass transition temperature, good mechanical properties, low dielectric constant and dielectric loss, and excellent application potential in high-frequency and high-speed PCBs. However, the high molecular weight of PPO has low molecular design, high melt viscosity, and poor fluidity, making it difficult to process by melt injection molding or extrusion, which limits its large-scale application. Summary of the Invention
[0004] The present invention aims to overcome the problems of the prior art and provide a method for preparing a functionalized oligomeric PPO-modified phthalonitrile resin. In the present invention, a low-molecular-weight PPO containing functional groups is selected for blending and copolymerizing with a phthalonitrile resin. Since blending or copolymerizing thermoplastic and thermosetting polymers can synergistically enhance the properties of the polymer, the present invention reduces the curing temperature of the phthalonitrile resin while also improving its dielectric properties and toughness, without significantly compromising the high heat resistance and thermal stability of the phthalonitrile resin.
[0005] In order to achieve the purpose of the above invention, the specific technical solution of the present invention is:
[0006] A method for preparing a functionalized oligomeric PPO-modified phthalonitrile resin comprises the following steps:
[0007] (1) dissolving a certain amount of oligomeric PPO containing R2 groups in an organic solvent at room temperature, and dissolving the oligomeric PPO by ultrasonication, heating or stirring to obtain a uniform solution;
[0008] (2) adding a certain amount of phthalonitrile resin containing R1 group to the uniform solution obtained in step (1) at room temperature, and dissolving again by ultrasound, heating or stirring to obtain functionalized oligomeric PPO modified phthalonitrile resin;
[0009] The structural formulas of the oligomeric PPO containing R2 groups and the phthalonitrile resin containing R1 groups are:
[0010]
[0011] Furthermore, in the preparation method of the functionalized oligomeric PPO modified phthalonitrile resin, R1 in the phthalonitrile resin containing R1 groups is at least one of an amino group, a cyano group, a benzoxazine group, an imidazole group, an allyl group or other aromatic structures.
[0012]
[0013] In the oligomeric PPO containing R2 groups, R2 is at least one of a hydroxyl group, an allyl group, an alkynyl group and a maleimide group;
[0014]
[0015] Preferably, in the preparation method of the functionalized oligomeric PPO modified phthalonitrile resin, the molar ratio of the phthalonitrile resin containing the R1 group to the oligomeric PPO containing the R2 group is 1:1 to 1:19, for example, 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 1:11, 1:12, 1:13, 1:14, 1:15, 1:16, 1:17, 1:18, 1:19, etc.
[0016] Preferably, in the preparation method of the functionalized oligomeric PPO modified phthalonitrile resin, the organic solvent is any one of toluene, DMF, NMP, dioxane, or a mixture of toluene, DMF, NMP, dioxane with ethanol or butanone.
[0017] Preferably, in the preparation method of the functionalized oligomeric PPO modified phthalonitrile resin, the dissolution time in step (1) and step (2) is 10-25 min, for example, 10 min, 15 min, 20 min, 25 min; the dissolution temperature is 25-45°C, for example, 25°C, 30°C, 35°C, 40°C, 45°C.
[0018] Preferably, the solid content of the solution obtained in step (2) is 30wt%-60wt%, for example, 30wt%, 35wt%, 40wt%, 45wt%, 50wt%, 55wt%, 60wt%.
[0019] Another object of the present invention is to provide a functionalized oligomeric PPO modified phthalonitrile resin prepared by any of the above methods.
[0020] Furthermore, the number average molecular weight of the functionalized oligomeric PPO in the resin is 1000-5000 g / mol.
[0021] The third invention object of the present invention is to use the resin obtained by the above method to further prepare a composite material containing functionalized oligomeric PPO modified phthalonitrile resin, comprising the following steps:
[0022] The obtained functionalized oligomeric PPO modified phthalonitrile resin is coated and cured at elevated temperature to obtain a polymer film; or the obtained functionalized oligomeric PPO modified phthalonitrile resin is coated on a reinforcement for prepreg, and a composite material is obtained after curing and pressing.
[0023] Preferably, in the method for preparing a functionalized oligomeric PPO-modified phthalonitrile resin, the prepreg reinforcement is selected from glass fiber cloth, carbon fiber cloth, quartz fiber cloth or aramid fiber cloth.
[0024] Preferably, in the preparation method of the functionalized oligomeric PPO-modified phthalonitrile resin, the curing temperature of the resin film or composite material is higher than 200°C, for example, 200°C, 205°C, 210°C, 215°C, 220°C, 225°C, 230°C, 245°C, 250°C, 255°C, 260°C, etc.
[0025] Compared with the prior art, the present invention has the following beneficial effects:
[0026] (1) In this method, the high-performance, high-carbon residue, and high-dielectric phthalonitrile resin obtained by copolymerization not only greatly improves the dielectric properties and flame retardancy of the resin, but also greatly reduces production costs; it provides new ideas for the synthesis of other polymers with similar reaction mechanisms.
[0027] (2) The functionalized oligomeric PPO of the present invention can significantly improve the dielectric properties of phthalonitrile resins. Compared with traditional phthalonitrile resins, it effectively reduces the curing temperature and shortens the curing time of phthalonitrile resins. It can effectively reduce the dielectric constant and dielectric loss, improve the dielectric properties, and at the same time, does not adversely affect the thermal properties of phthalonitrile resins.
[0028] (3) Functionalized oligomeric PPO can reduce the curing temperature of phthalonitrile resin to a certain extent, increase the curing degree, and at the same time ensure its excellent heat resistance.
[0029] (4) Functionalized oligomeric PPO can improve the brittleness of phthalonitrile resin to a certain extent.
[0030] (5) Since the functionalized oligomeric PPO contains active functional groups and has a relatively small molecular weight, it can be combined with the phthalonitrile resin by chemical bonding without causing phase separation, which is beneficial to the consistency of the blended resin and reduces defects. BRIEF DESCRIPTION OF THE DRAWINGS
[0031] Figure 1 DSC curves of modified phthalonitrile monomers with different allyl-containing oligomeric PPO contents
[0032] Figure 2 Rheological modulus of 10wt% hydroxyl-containing oligomeric PPO modified phthalonitrile
[0033] Figure 3 The dielectric constant curve of phthalonitrile cured products modified with oligomeric PPO containing different allyl groups at 220℃
[0034] Figure 4 TGA curves of phthalonitrile cured products modified with oligomeric PPO containing different hydroxyl groups at 220°C DETAILED DESCRIPTION
[0035] The present invention will be described in further detail below in conjunction with specific embodiments. However, this should not be construed as limiting the scope of the present invention to the following embodiments, as all technologies implemented based on the present invention fall within the scope of the present invention.
[0036] In the following examples, the chemical structure of the phthalonitrile resin used is The chemical structure of the oligomeric PPO containing functional groups used is Example 1:
[0037] Step 1: 0.1 mol of hydroxyl-terminated oligomeric PPO having a molecular weight of 2000 g / mol was dissolved in NMP at room temperature to obtain a mixture.
[0038] Step 2: Place the mixture in an ultrasonicator and sonicate at 35° C. for 20 min until the hydroxyl-terminated oligomeric PPO is completely dissolved to obtain a solution.
[0039] Step 3: Add 0.9 mol of aminophthalonitrile resin to the solution obtained in step 2 at room temperature and mix well to obtain a blend. The solid content of the blend is 60 wt%.
[0040] Step 4: The blend obtained in step 3 is evenly coated on a glass fiber cloth, and then dried in a vacuum oven at 160° C. for 20 minutes to obtain a prepreg cloth; this operation is repeated to obtain a multi-layer prepreg cloth.
[0041] Step 5: 8 layers of prepreg cloth obtained in step 4 were hot-pressed and cured in a press at 200°C for two hours to obtain a laminate with a thickness of approximately 1.2 mm.
[0042] The hydroxyl-terminated oligomeric PPO with a molecular weight of 2000 g / mol was purchased from Jining Huakai Resin Co., Ltd., NMP was purchased from Chengdu Kelong Chemical Company, aminophthalonitrile resin was homemade in the laboratory, and glass fiber cloth was purchased from Chongqing Canyue New Materials Co., Ltd.
[0043] The obtained hydroxy polyphenylene ether-aminophthalonitrile resin glass fiber reinforced composite laminate was tested and found to have a flexural strength of 480 MPa, a flexural modulus of 4.7 GPa, a CTE of 38 ppm / °C, a glass transition temperature of 247°C, an initial decomposition temperature of 462°C, a dielectric constant of 4.48 at 1 MHz, a dielectric loss of 0.018, and a saturated water absorption rate of 1.17%.
[0044] Example 2:
[0045] Step 1: Dissolve 0.05 mol of allyl-terminated oligomeric PPO having a molecular weight of 4000 g / mol in a DMF / acetone mixed solvent at room temperature to obtain a mixture.
[0046] Step 2: The mixture was placed in an ultrasonicator and ultrasonicated at 30° C. for 15 min until the allyl-terminated oligomeric PPO was completely dissolved to obtain a solution.
[0047] Step 3: Add 0.95 mol of phthalonitrile resin containing benzoxazine groups into the solution at room temperature and mix well to obtain a blend solution with a solid content of 30 wt%.
[0048] Step 4: The blend solution obtained in step 3 is coated in a blast oven and cured by heating. The curing procedure is 120°C, 140°C, 160°C, 200°C for one hour respectively, and 240°C for two hours to obtain a resin film.
[0049] The allyl-terminated oligomeric PPO with a molecular weight of 4000 g / mol was purchased from Jining Huakai Resin Co., Ltd., DMF and acetone were purchased from Chengdu Kelong Chemical Company, and the phthalonitrile resin containing benzoxazine groups was homemade in the laboratory.
[0050] The obtained allyl polyphenylene ether-benzoxazine phthalonitrile resin film has an initial decomposition temperature of 490° C., a glass transition temperature of 260° C., a dielectric constant of 2.98 at 1 MHz, a dielectric loss of 0.008, and a saturated water absorption rate of 0.54%.
[0051] Example 3:
[0052] Step 1: dissolving 0.3 mol of maleimide-terminated oligomeric PPO having a molecular weight of 5000 g / mol in a toluene / ethanol mixed solvent at room temperature to obtain a mixture.
[0053] Step 2: Place the mixture in step 1 into an ultrasonicator and ultrasonicate at 25° C. for 20 min until an allyl-terminated oligomeric PPO solution is obtained.
[0054] Step 3: Add 0.7 mol of phthalonitrile resin containing an imidazole structure to the solution obtained in step 2 at room temperature to prepare a blend with a solid content of 50%.
[0055] Step 4: The blend obtained in step 3 is evenly coated on a glass fiber cloth, and then dried in a vacuum oven at 160° C. for 20 minutes to obtain a prepreg cloth.
[0056] Step 5: 8 layers of prepreg cloth obtained in step 4 were hot-pressed and cured in a press at 240°C for two hours to obtain a laminate with a thickness of approximately 1.2 mm.
[0057] The maleimide-terminated oligomeric PPO with a molecular weight of 5000 g / mol was purchased from Jining Huakai Resin Co., Ltd., toluene and ethanol were purchased from Chengdu Kelong Chemical Company, the phthalonitrile resin containing imidazole structure was homemade in the laboratory, and the glass fiber cloth was purchased from Chongqing Canyue New Materials Co., Ltd.
[0058] The obtained maleimide-based polyphenylene ether-phthalonitrile resin glass fiber reinforced composite laminate was tested to have a flexural strength of 542 MPa, a flexural modulus of 3.47 GPa, and a fracture toughness greater than 164 J / m 2 , CTE is 43ppm / ℃, glass transition temperature is 288℃, initial decomposition temperature is 481℃, dielectric constant is 4.26 at 1MHz, dielectric loss is 0.019, and saturated water absorption is 1.01%.
[0059] Example 4:
[0060] Step 1: Dissolve 0.3 mol of amino-terminated oligomeric PPO with a molecular weight of 2000 g / mol in a DMF / acetone mixed solvent at room temperature to obtain a mixture.
[0061] Step 2: The mixture was placed in an ultrasonicator and ultrasonicated at 30° C. for 30 min until the amino-terminated oligomeric PPO was completely dissolved to obtain a solution.
[0062] Step 3: Add 0.7 mol of allyl phthalonitrile resin to the solution at room temperature and mix well to obtain a blend solution with a solid content of 60 wt%.
[0063] Step 4: Pour the blend obtained in step 3 into an iron mold preheated at 130°C and vacuum to remove the solvent.
[0064] Step 5: The melt obtained in step 2 is kept at 240° C. for curing for 2 hours, and then cooled and demolded to obtain a resin casting body.
[0065] Among them, amino-terminated oligomeric PPO with a molecular weight of 2000 g / mol was purchased from Jining Huakai Resin Co., Ltd., DMF and acetone were purchased from Chengdu Kelong Chemical Company, allyl phthalonitrile resin was homemade in the laboratory, and glass fiber cloth was purchased from Chongqing Canyue New Materials Co., Ltd.
[0066] The obtained amino polyphenylene ether-allyl phthalonitrile resin casting was tested: its bending strength was 572Mpa, the bending modulus was 4.63GPa, and the fracture toughness was greater than 170J / m 2 , CTE is 49ppm / ℃, glass transition temperature is 288℃, dielectric constant is 3.11 at 1MHz, dielectric loss is 0.007, and saturated water absorption is 1.13%.
[0067] Comparative Example 1:
[0068] The same method and steps as in Example 1 were used, except that the molecular weight of the oligomeric PPO was set to be higher than 10,000 g / mol. As a result, the obtained blended composite material exhibited phase separation, resulting in microscopic and macroscopic uneven distribution, affecting the mechanical and dielectric properties of the material.
[0069] Comparative Example 2:
[0070] A hydroxy polyphenylene ether-aminophthalonitrile resin glass fiber reinforced composite laminate was prepared using the same method and steps as in Example 1; the only difference being that the curing temperature during the two-hour hot pressing curing in a press at 200°C was changed to 180°C. The resulting cured product had a low crosslinking density and low mechanical strength and could not be used as a material.
[0071] Comparative Example 3:
[0072] The same method and steps as in Example 1 were used, except that the hydroxyl-terminated oligomeric PPO was replaced with PPO without functional groups, and then copolymerized with the phthalonitrile resin. In this case, the cured product was prone to phase separation, secondary relaxation occurred at lower temperatures (<150°C), and the heat resistance was poor.
[0073] The above-described embodiments are merely preferred implementations of the present invention, but the scope of protection of the present invention is not limited thereto. It should be noted that, without departing from the principles of the present invention, those skilled in the art may make various improvements and modifications based on the technical solution and patent concept of the present invention, and such improvements and modifications shall also be considered within the scope of protection of the present invention.
Claims
1. A method for preparing a functionalized oligomeric PPO modified phthalonitrile resin, characterized in that The number average molecular weight of the functionalized oligomeric PPO is 1000-5000 g / mol; the specific method comprises the following steps: (1) Dissolving a certain amount of oligomeric PPO containing R2 groups in an organic solvent at room temperature, and dissolving it by ultrasonication, heating or stirring to obtain a uniform solution; (2) adding a certain amount of phthalonitrile resin containing R1 group to the uniform solution obtained in step (1) at room temperature, and dissolving again by ultrasonication, heating or stirring to obtain functionalized oligomeric PPO modified phthalonitrile resin; The dissolution time in step (1) and step (2) is 10-25 minutes, and the dissolution temperature is 25-45°C; The structural formulas of the oligomeric PPO containing R2 groups and the phthalonitrile resin containing R1 groups are: 、 ; R1 in the phthalonitrile resin containing R1 groups is a benzoxazine group; R2 in the oligomeric PPO containing R2 groups is an allyl group.
2. The method for preparing a functionalized oligomeric PPO modified phthalonitrile resin according to claim 1, wherein: The molar ratio of the phthalonitrile resin containing the R1 group to the oligomeric PPO containing the R2 group is 1:1 to 1:
19.
3. The method for preparing a functionalized oligomeric PPO modified phthalonitrile resin according to claim 1, wherein: The organic solvent is any one of toluene, DMF, NMP, dioxane, or a mixture of toluene, DMF, NMP, dioxane with ethanol or butanone.
4. The method for preparing a functionalized oligomeric PPO modified phthalonitrile resin according to claim 1, wherein: The solid content of the solution dissolved in step (2) is 30wt%-60wt%.
5. The functionalized oligomeric PPO modified phthalonitrile resin prepared according to the method according to any one of claims 1 to 4.
6. A method for preparing a functionalized oligomeric PPO-modified phthalonitrile resin composite material using the resin according to claim 5, characterized in that The following steps are involved: The obtained functionalized oligomeric PPO modified phthalonitrile resin is coated and cured at elevated temperature to obtain a polymer film; or the obtained functionalized oligomeric PPO modified phthalonitrile resin is coated on a reinforcement for prepreg, and a composite material is obtained after curing and pressing.
7. The method for preparing the functionalized oligomeric PPO modified phthalonitrile resin composite material according to claim 6, wherein: The reinforcement for the prepreg is selected from glass fiber cloth, carbon fiber cloth, quartz fiber cloth or aramid fiber cloth.
8. The method for preparing the functionalized oligomeric PPO modified phthalonitrile resin composite material according to claim 6, wherein: The curing temperature of the resin film or composite material is higher than 200°C.