Modified polyphenyl ether resin as well as preparation method and application thereof

Abstract

The invention provides modified polyphenyl ether resin as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing polyphenyl ether with hydroxyl groups at two ends, an end-capping reagent, a catalyst and an organic solvent, and carrying out modification treatment and post-treatment to obtain the modified polyphenyl ether resin. The modified polyphenyl ether resin provided by the invention has good dielectric properties.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, and more specifically, to a modified polyphenylene ether resin, a preparation method thereof, and an application thereof. Background Art

[0002] Polyphenylene ether, also known as poly(phenylene oxide) or polyphenylene ether, is a general engineering plastic. Polyphenylene ether is a resin polymer synthesized by the oxidative coupling reaction of disubstituted phenol in the presence of a metal salt / amine under the action of oxygen. Polyphenylene ether has excellent water and steam resistance, and the products have high tensile strength, impact strength, and creep resistance. In addition, due to the high symmetry of the polyphenylene ether molecular chain, it has a small polarity, excellent dimensional stability, and electrical properties with a low and stable dielectric constant and small dielectric loss. Therefore, polyphenylene ether is widely used in the fields of electricity, automobiles, cables, photovoltaic power generation, etc.

[0003] Copper clad laminate (CCL) is an important sheet material for printed circuit board (PCB). With the gradual development of the PCB industry towards high-speed transmission, light and thin directions, the demand for copper clad laminate is increasing. Low molecular weight polyphenylene ether capped with (meth)acrylic anhydride or 4-chloromethylstyrene has been widely used, but the two capping agents and the additives added in the synthesis process are expensive, resulting in high costs of low molecular weight polyphenylene ether with double bonds in copper clad laminates, and there are also problems such as uneven molecular weight of modified polyphenylene ether products and high catalyst residues. Therefore, there is an urgent need in the market for functionalized polyphenylene ether resins with low costs and simultaneously maintaining or improving the dielectric constant and dissipation factor. Summary of the Invention

[0004] In order to solve the above problems in the prior art, the purpose of the present invention is to provide a modified polyphenylene ether resin, a preparation method thereof, and an application thereof. The modified polyphenylene ether resin of the present invention has good dielectric properties.

[0005] In order to achieve the above purpose, according to a preparation method of a modified polyphenylene ether resin of the present invention, it includes:

[0006] Mix polyphenylene ether with hydroxyl groups at both ends, a capping agent, a catalyst, and an organic solvent, carry out modification treatment, and then carry out post-treatment to obtain the modified polyphenylene ether resin;

[0007] The polyphenylene ether with hydroxyl groups at both ends has a structure as shown in Formula I:

[0008]

[0009] Wherein, R1 and R2 are each independently selected from primary alkyl groups of C1-C6, secondary alkyl groups of C1-C6, aryl groups of C6-C12, and Y is selected from any one or a combination of two or more of Formulas 1 to 6;

[0010]

[0011] Among them, R3, R4, and R5 are each independently H, an alkyl group having 1 to 12 carbon atoms, a halogen, a halogenated alkyl group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms containing a phenolic hydroxyl group, or an alkoxy group having 1 to 12 carbon atoms;

[0012] m and n are each independently selected from 1 to 50;

[0013] The capping agent has a structure shown in Formula II:

[0014]

[0015] Among them, Ra is selected from alkyl groups having 1 to 12 carbon atoms.

[0016] The present invention provides a method for preparing a modified polyphenylene ether at low cost, which has double bonds and hydroxyl groups at both ends, and the capping group is connected to the polyphenylene ether resin through an ether bond, which is more hydrolysis-resistant than an ester bond. Moreover, the two end groups of the modified polyphenylene ether resin of the present invention not only contain polymerizable double bonds, but also have OH groups. Therefore, the modified polyphenylene ether resin can not only improve the heat resistance of the copper clad laminate, but also further improve the dielectric constant and dielectric loss.

[0017] In some preferred embodiments of the present invention, the preparation method of the capping agent of Formula II can refer to ACSSustainable Chem.Eng.2023,11,8308-8316.

[0018] In some preferred embodiments of the present invention, Ra is selected from straight-chain alkyl groups having 2 to 4 carbon atoms.

[0019] In some preferred embodiments of the present invention, R1 and R2 are each independently methyl, ethyl, propyl, or butyl; preferably, R1 and R2 are methyl;

[0020] In some preferred embodiments of the present invention, Y is selected from a methylene group or an ether bond.

[0021] In some preferred embodiments of the present invention, m and n are each independently selected from 1 to 30; preferably, m and n are each independently selected from 1 to 20; preferably, m and n are each independently selected from 1 to 10; preferably, m and n are each independently selected from 1 to 8.

[0022] In some preferred embodiments of the present invention, the sum of m and n ≥ 3; preferably, the sum of m and n ≥ 4.

[0023] Through the above preferred conditions, it is beneficial to better control the product structure, obtain a modified polyphenylene ether resin with a lower molecular weight, and further improve its electrical properties.

[0024] In some preferred embodiments of the present invention, R6 is selected from linear alkyl groups having 2 to 4 carbon atoms.

[0025] In some preferred embodiments of the present invention, the molar amount of the capping agent is 2 to 6 times, preferably 2.1 to 4 times, that of the polyphenylene ether having hydroxyl groups at both ends.

[0026] In some preferred embodiments of the present invention, the molar amount of the catalyst is 1 to 10 times, preferably 4 to 6 times, that of the polyphenylene ether having hydroxyl groups at both ends.

[0027] In some preferred embodiments of the present invention, the mass concentration of the polyphenylene ether having hydroxyl groups at both ends in the organic solvent is 20 to 40%.

[0028] In some preferred embodiments of the present invention, the organic solvent includes one or a combination of two or more of benzene, toluene, ethylbenzene, chlorobenzene, bromobenzene, dichloromethane, chloroform, carbon tetrachloride, trichloroethane, tetrahydrofuran, and carbon disulfide; preferably, the organic solvent includes one or a combination of two or more of benzene, toluene, ethylbenzene, carbon tetrachloride, and chloroform; preferably, the organic solvent includes toluene and / or ethylbenzene.

[0029] In some preferred embodiments of the present invention, the catalyst includes one or a combination of two or more of sodium hydroxide, potassium hydroxide, sodium hydride, sodium methoxide, sodium ethoxide, boron trifluoride diethyl ether complex, and quaternary ammonium salts; wherein, the quaternary ammonium salts include one or a combination of two or more of tetrabutylammonium bromide, trimethylbenzylammonium chloride, trioctylmethylammonium chloride, cetyltrimethylammonium bromide, and triethylbenzylammonium chloride; preferably, the catalyst includes one or a combination of two or more of sodium hydroxide, potassium hydroxide, sodium methoxide, and boron trifluoride diethyl ether complex.

[0030] In some preferred embodiments of the present invention, the temperature of the modification treatment is 20 to 150 °C;

[0031] Preferably, the temperature of the modification treatment is 90 to 140 °C.

[0032] The reaction conditions of the present invention are relatively mild.

[0033] In some preferred embodiments of the present invention, the post-treatment includes: precipitating the solution obtained after the modification treatment in a poor solvent and then drying.

[0034] According to another aspect of the present invention, there is provided a modified polyphenylene ether resin prepared by the above preparation method, which has a structure as shown in Formula III:

[0035]

[0036] In some preferred embodiments of the present invention, the number-average molecular weight of the modified polyphenylene ether resin is 500 to 10,000;

[0037] Preferably, the number-average molecular weight of the modified polyphenylene ether resin is 1,500 to 3,000.

[0038] According to another aspect of the present invention, there is provided an application of the above-mentioned modified polyphenylene ether resin in the preparation of a copper clad laminate.

[0039] Compared with the prior art, the present invention provides a preparation method of a modified polyphenylene ether resin with low cost and simple process. When the modified polyphenylene ether resin is applied to a copper clad laminate, it exhibits good heat resistance and dimensional stability, and at the same time, the dielectric constant and dielectric loss are further improved. Detailed Embodiments

[0040] In order to have a clearer understanding of the technical features, objectives and beneficial effects of the present invention, the technical solutions of the present invention are described in detail below, but it should not be construed as a limitation on the implementable scope of the present invention.

[0041] Example 1:

[0042] This example provides a modified polyphenylene ether resin, and the preparation method includes:

[0043] 150 g of a polyphenylene ether resin with a number-average molecular weight of 1,500 and having the structure of Formula I-1 and 225 g of toluene were added to a 1,000 mL four-necked flask equipped with a stirrer, a condenser, a thermometer and a nitrogen inlet tube. The temperature was raised to 90 °C. After complete dissolution, the atmosphere in the four-necked flask was replaced with nitrogen, and then 1 g of sodium hydroxide as a catalyst was added. Then, 30.24 g of a capping agent having the structure of Formula II-1 was added dropwise, and the addition was completed within 1 hour. Stirring was continued for 4 hours, and the temperature was lowered to 30 - 40 °C. Then, the above reaction solution was added dropwise to 1,000 g of methanol, and a white solid was precipitated and filtered. The white solid was dried in a vacuum oven at 80 °C for 8 h to obtain a modified polyphenylene ether resin P1, and the number-average molecular weight of P1 was 1,750.

[0044] The nuclear magnetic resonance results showed that the terminal hydroxyl peak attributed to the unmodified PPO-2OH at δ = 4.38 ppm completely disappeared, characteristic peaks of the double bond of vinyl ether appeared at chemical shifts of δ = 4.15 ppm and 6.46 ppm, and a characteristic peak of the hydroxyl group formed by the ring opening of glycidyl ether appeared at δ = 3.75 ppm. The results indicated that the modified polyphenylene ether resin was successfully synthesized.

[0045] Formula I-1 is:

[0046]

[0047] Formula Ⅱ-1 is as follows:

[0048]

[0049] Example 2:

[0050] This example provides a modified polyphenylene ether resin, and the preparation method includes:

[0051] Add 150 g of polyphenylene ether resin with a number-average molecular weight of 2000 and having the structure of Formula Ⅰ-1 and 350 g of toluene into a 1000 mL four-necked flask equipped with a stirrer, a condenser, a thermometer and a nitrogen inlet tube. Heat up to 100 °C. After complete dissolution, replace the atmosphere in the four-necked flask with nitrogen, and then add 2.12 g of boron trifluoride ether complex as a catalyst. Then, dropwise add 25.9 g of a capping agent having the structure of Formula Ⅱ-1, and finish dropping within 1 hour. Continue stirring for 6 hours, cool down to 30 - 40 °C, and then drop the above reaction solution into 1000 g of methanol. Precipitate and filter to obtain a white solid. After drying in a vacuum oven at 80 °C for 8 h, the modified polyphenylene ether resin P2 is obtained. The number-average molecular weight of P2 is 2252.

[0052] The NMR results show that the terminal hydroxyl peak attributed to the unmodified PPO-2OH at δ = 4.38 ppm completely disappears, characteristic peaks of the double bond of vinyl ether appear at chemical shifts of δ = 4.13 ppm and 6.42, and a characteristic peak of the hydroxyl group formed by the ring opening of glycidyl ether appears at δ = 3.72 ppm. The results indicate that the modified polyphenylene ether resin P2 is successfully synthesized.

[0053] Example 3:

[0054] This example provides a modified polyphenylene ether resin, and the preparation method includes:

[0055] Add 150 g of polyphenylene ether resin with a number-average molecular weight of 3000 and having the structure of Formula Ⅰ-1 and 600 g of ethylbenzene into a 1000 mL four-necked flask equipped with a stirrer, a condenser, a thermometer and a nitrogen inlet tube. Heat up to 140 °C. After complete dissolution, replace the atmosphere in the four-necked flask with nitrogen, and then add 0.45 g of sodium methoxide as a catalyst. Then, dropwise add 28.8 g of a capping agent having the structure of Formula Ⅱ-1, and finish dropping within 1 hour. Continue stirring for 8 hours, cool down to 30 - 40 °C, and then drop the above reaction solution into 1000 g of methanol. Precipitate and filter to obtain a white solid. After drying in a vacuum oven at 80 °C for 8 h, the modified polyphenylene ether resin P3 is obtained. The number-average molecular weight of P3 is 3256.

[0056] The NMR results showed that the terminal hydroxyl peak attributed to PPO-2OH before modification at δ = 4.38 ppm completely disappeared, characteristic peaks of the double bond of vinyl ether appeared at chemical shifts δ = 4.09 ppm and 6.38 ppm, and a characteristic peak of the hydroxyl group formed by the ring-opening of glycidyl ether appeared at δ = 3.69 ppm. The results indicated the successful synthesis of the modified polyphenylene ether resin P3.

[0057] Example 4:

[0058] This example provides a modified polyphenylene ether resin, and the preparation method includes:

[0059] Add 150 g of polyphenylene ether resin with a number average molecular weight of 2000 having the structure of Formula I-2 and 350 g of toluene into a 1000 mL four-necked flask equipped with a stirrer, a condenser, a thermometer, and a nitrogen inlet tube. Heat up to 100 °C. After complete dissolution, replace the atmosphere in the four-necked flask with nitrogen, then add 2.12 g of boron trifluoride etherate as a catalyst, and then dropwise add 25.9 g of a capping agent having the structure of Formula II-1. Finish the dropwise addition within 1 hour, continue stirring for 6 hours, cool down to 30 - 40 °C, then drop the above reaction solution into 1000 g of methanol, precipitate and filter to obtain a white solid, and dry it in a vacuum oven at 80 °C for 8 h to obtain the modified polyphenylene ether resin P4, and the number average molecular weight of P4 is 2253.

[0060] The NMR results showed that the terminal hydroxyl peak attributed to PPO-2OH before modification at δ = 4.35 ppm completely disappeared, characteristic peaks of the double bond of vinyl ether appeared at chemical shifts δ = 4.21 ppm and 6.51 ppm, and a characteristic peak of the hydroxyl group formed by the ring-opening of glycidyl ether appeared at δ = 3.78 ppm. The results indicated the successful synthesis of the modified polyphenylene ether resin.

[0061] Formula I-2 is:

[0062]

[0063] Example 5:

[0064] This example provides a modified polyphenylene ether resin, and the preparation method includes:

[0065] In a 1000 mL four-necked flask equipped with a stirrer, a condenser, a thermometer and a nitrogen inlet tube, 150 g of a polyphenylene ether resin with a number-average molecular weight of 2000 having the structure of Formula I-1 and 350 g of toluene were added. The temperature was raised to 100 °C. After complete dissolution, the atmosphere in the four-necked flask was replaced with nitrogen, and then 2.12 g of boron trifluoride ether complex as a catalyst was added. Then, 28.5 g of a capping agent having the structure of Formula II-2 was added dropwise, and the addition was completed within 1 hour. Stirring was continued for 6 hours, and the temperature was lowered to 30-40 °C. Then, the above reaction solution was added dropwise to 1000 g of methanol, and a white solid was precipitated and filtered. After drying in a vacuum oven at 80 °C for 8 h, the modified polyphenylene ether resin P5 was obtained. The number-average molecular weight of P5 was 2252.

[0066] The NMR results showed that the terminal hydroxyl peak attributed to the unmodified PPO-2OH at δ = 4.38 ppm completely disappeared, characteristic peaks of the double bond of vinyl ether appeared at chemical shifts of δ = 4.05 ppm and 6.33, and a characteristic peak of the hydroxyl group formed by the ring-opening of glycidyl ether appeared at δ = 3.65 ppm. The results indicated that the modified polyphenylene ether resin P5 was successfully synthesized.

[0067] Formula II-2 is:

[0068]

[0069] Example 6:

[0070] This example provides a modified polyphenylene ether resin, and the preparation method includes:

[0071] Synthesized according to the steps of Example 1, except that 1.5 g of potassium hydroxide was used to replace 1 g of sodium hydroxide, and the modified polyphenylene ether resin P6 was obtained. The number-average molecular weight of P6 was 2250.

[0072] The NMR results showed that the terminal hydroxyl peak attributed to the unmodified PPO-2OH at δ = 4.38 ppm completely disappeared, characteristic peaks of the double bond of vinyl ether appeared at chemical shifts of δ = 4.16 ppm and 6.48, and a characteristic peak of the hydroxyl group formed by the ring-opening of glycidyl ether appeared at δ = 3.76 ppm. The results indicated that the modified polyphenylene ether resin P6 was successfully synthesized.

[0073] Comparative Example 1:

[0074] This comparative example provides a modified polyphenylene ether resin, and the preparation method includes:

[0075] In a 1000 mL four-necked flask equipped with a stirrer, a condenser, a thermometer, and a nitrogen inlet tube, 150 g of a polyphenylene ether resin with a number-average molecular weight of 2000 and having the structure of Formula I-1 and 350 g of toluene were added. The temperature was raised to 30 °C. After complete dissolution, the atmosphere in the four-necked flask was replaced with nitrogen, and then 9.5 g of trioctylmethylammonium chloride as a catalyst was added. Then, 28.5 g of allyl glycidyl ether as a capping agent was added dropwise, and the addition was completed within 1 hour. Stirring was continued for 6 hours, and the temperature was lowered to 30 - 40 °C. Then, the above reaction solution was added dropwise to 1000 g of methanol, and a white solid was precipitated and filtered. After drying in a vacuum oven at 80 °C for 8 h, the modified polyphenylene ether resin S1 was obtained. The number-average molecular weight of S1 was 2170.

[0076] The NMR results showed that the terminal hydroxyl peak attributed to PPO-2OH before modification at δ = 4.38 ppm completely disappeared, characteristic peaks of the double bond of allyl appeared at chemical shifts of δ = 5.24 ppm and 5.96, and a characteristic peak of the hydroxyl group formed by the ring-opening of glycidyl ether appeared at δ = 3.64 ppm. The results indicated that the modified polyphenylene ether resin S1 was successfully synthesized.

[0077] Comparative Example 2:

[0078] This comparative example provides a modified polyphenylene ether resin, and the preparation method includes:

[0079] In a 1000 mL four-necked flask equipped with a stirrer, a condenser, a thermometer, and a nitrogen inlet tube, 150 g of a polyphenylene ether resin with a number-average molecular weight of 2000 and having the structure of Formula I-1 and 350 g of toluene were added. The temperature was raised to 80 °C. After complete dissolution, the atmosphere in the four-necked flask was replaced with nitrogen, and then 9.5 g of trioctylmethylammonium chloride as a catalyst was added. Then, 34.8 g of epichlorohydrin as a capping agent was added dropwise, and the addition was completed within 1 hour. Stirring was continued for 8 hours, and the temperature was lowered to 30 - 40 °C. Then, the above reaction solution was added dropwise to 1000 g of methanol, and a white solid was precipitated and filtered. After drying in a vacuum oven at 80 °C for 8 h, the epoxy propane-capped modified polyphenylene ether resin S2 was obtained.

[0080] The NMR results showed that the terminal hydroxyl peak attributed to PPO-2OH before modification at δ = 4.38 ppm completely disappeared, and characteristic peaks of the epoxy functional group appeared at chemical shifts of δ = 3.55 - 3.64 ppm. The results indicated that the modified polyphenylene ether resin S2 was successfully synthesized.

[0081] To further illustrate the beneficial effects of the present invention, the compounds and their compositions provided by the present invention were used to prepare prepregs and copper clad laminates, and their dielectric constant Dk and dielectric loss factor Df were tested according to the test methods in the industry standard IPC-TM-650.

[0082] The glass transition temperature (Tg) was measured using a TA Discovery 250 differential scanning calorimeter (DSC) within a temperature range of 0 to 300 °C at a heating rate of 10 °C / min.

[0083] In the specific embodiments of the present invention, the number-average molecular weight of the modified polyphenylene ether resin was measured using an Agilent 1260 gel permeation chromatography (GPC) with a differential detector, a PL-gel, mixed-D chromatographic column of 300 mm (L) × 7.5 mm (ID), chloroform as the solvent, and a narrow-distribution polystyrene from Agilent as the standard, with a molecular weight range of 162 to 364000. The prepregs and copper-clad laminates were prepared according to the industry's general methods as follows: The modified polyphenylene ether resin or the composition containing the modified polyphenylene ether resin and other components were added to toluene in the proportions shown in Table 1, with the solid component concentration being 60 wt%, and then stirred for 60 minutes to obtain a composition solution. After impregnating this composition solution into a glass cloth (type 1506), it was heated and dried at 130 °C for approximately 3 minutes to obtain the prepreg. Eight prepregs were stacked, copper foils were covered on both the upper and lower sides thereof, and cured at 240 °C and 5 MPa for 2 h in a press to obtain the copper-clad laminate.

[0084] Table 1

[0085]

[0086] From the experimental results of the above examples and comparative examples, it can be seen that the plates made of the modified polyphenylene resin prepared by the present invention all have good thermal stability and lower Dk and Df values, indicating that the polyphenylene ether resin of the present invention maintains the good Dk and Df properties of the original polyphenylene ether resin.

Claims

1. A method for preparing a modified polyphenylene ether resin, characterized in that: include: The polyphenylene ether with hydroxyl groups at both ends, a capping agent, a catalyst, and an organic solvent are mixed, and subjected to modification treatment and post-treatment to obtain the modified polyphenylene ether resin; The polyphenylene ether with hydroxyl groups at both ends has a structure as shown in Formula I: Wherein, R1 and R2 are each independently selected from a C1-C6 primary alkyl group, a C1-C6 secondary alkyl group or a C6-C12 aryl group, and Y is selected from any one or a combination of two or more of Formulas 1 to 6; Wherein, R3, R4, and R5 are each independently H, C1-C12 alkyl, halogen, C1-C12 haloalkyl, C6-C12 aryl containing phenolic hydroxyl group, or C1-C12 alkoxy; m and n are independently selected from 1 to 50; The capping agent has a structure as shown in Formula II: Wherein, Ra is selected from C1 to C12 alkyl groups.

2. The preparation method according to claim 1, characterized in that: Ra is selected from a C2-C4 straight chain alkyl group; and / or, R1 and R2 are each independently methyl, ethyl, propyl or butyl; and / or, Y is selected from a methylene or ether bond; and / or, m and n are each independently selected from 1 to 30; and / or, The sum of m and n is ≥ 3; and / or, R6 is selected from C2-C4 straight chain alkyl groups.

3. The preparation method according to claim 1, characterized in that: The molar amount of the end-capping agent is 2 to 6 times that of the polyphenylene ether with hydroxyl groups at both ends.

4. The preparation method according to claim 1, characterized in that: The molar amount of the catalyst is 1 to 10 times that of the polyphenylene ether with hydroxyl groups at both ends.

5. The preparation method according to claim 1, characterized in that: The mass concentration of the polyphenylene ether having hydroxyl groups at both ends in the organic solvent is 20-40%; and / or, The organic solvent includes one or a combination of two or more of benzene, toluene, ethylbenzene, chlorobenzene, bromobenzene, dichloromethane, chloroform, tetrachloromethane, trichloroethane, tetrahydrofuran, and carbon disulfide; and / or, The catalyst includes one or a combination of two or more of sodium hydroxide, potassium hydroxide, sodium hydride, sodium methoxide, sodium ethoxide, boron trifluoride ether complex, and quaternary ammonium salt; wherein the quaternary ammonium salt includes one or a combination of two or more of tetrabutylammonium bromide, trimethylbenzylammonium chloride, trioctylmethylammonium chloride, hexadecyltrimethylammonium bromide, and triethylbenzylammonium chloride.

6. The preparation method according to claim 1, characterized in that: The temperature of the modification treatment is 20-150°C.

7. A modified polyphenylene ether resin prepared by the preparation method according to any one of claims 1 to 6.

8. The modified polyphenylene ether resin according to claim 7, characterized in that The modified polyphenylene ether resin has a structure as shown in Formula III:

9. The modified polyphenylene ether resin according to claim 7, characterized in that: The number average molecular weight of the modified polyphenylene ether resin is 500 to 10,000.

10. Use of the modified polyphenylene ether resin prepared by the preparation method according to any one of claims 1 to 6 or the modified polyphenylene ether resin according to any one of claims 7 to 9 in preparing a copper clad laminate.

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