Modified bismaleimide resin composition, prepreg and copper foil substrate

Abstract

The invention discloses a modified bismaleimide resin composition which comprises the following components in parts by weight: 10-80 parts of bismaleimide, 5-50 parts of benzocyclobutene derivatives containing silicon-oxygen bonds and 10-60 parts of epoxy resin, and the modified bismaleimide resin composition is prepared from the following components in parts by weight: 10-80 parts of bismaleimide, 5-50 parts of benzocyclobutene derivatives containing silicon-oxygen bonds and 10-60 parts of epoxy resin. The bismaleimide and the benzocyclobutene derivative containing the silicon-oxygen bond are compounded, the benzocyclobutene derivative containing the silicon-oxygen bond can be subjected to ring opening isomerization under the action of heat to form very active diene, the isomerized diene and the bismaleimide are subjected to Diels-Alder addition, and the product obtained after addition has extremely high Tg and thermal decomposition temperature, so that the flame retardant property of the flame retardant is improved, and the flame retardant property of the flame retardant is improved. And the silicon-oxygen bond has good flexibility, can further improve the toughness of the resin, and has a certain stress absorption effect in the resin composition, so that good heat resistance and high-temperature modulus value are maintained, the water absorption rate of a resin system is further improved, and the CTE in the resin system is further reduced.

Description

Technical Field

[0001] The invention relates to the field of resin compositions, in particular to a modified bismaleimide resin composition, a prepreg and a copper foil substrate. Background Art

[0002] In recent years, with the rapid development of mobile Internet technology, people's demand for mobile data has continued to increase, and high-density interconnection technology (HDI) electronic products have also put forward higher requirements on their printed circuit board substrates.

[0003] At present, most of the industry uses bismaleimide as the raw material of the substrate. Although conventional bismaleimide has a high glass transition temperature and excellent heat resistance, it still has shortcomings such as poor toughness, high thermal expansion, and poor water absorption, which makes it difficult to meet the requirements of high-performance packaging substrates. Therefore, it is necessary to propose a new solution to improve the above problems. Summary of the invention

[0004] In view of this, the present invention aims to address the deficiencies in the prior art, and its main purpose is to provide a modified bismaleimide resin composition, a prepreg and a copper foil substrate, which introduces silicon-oxygen bonds into the resin system so that the resin has better flexibility and plays a certain stress absorption role in the resin composition, thereby maintaining good heat resistance and high temperature modulus value, while further improving the water absorption of the resin system and reducing the CTE in the resin system.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions:

[0006] A modified bismaleimide resin composition comprises the following components based on 100 parts by weight: 10-80 parts of bismaleimide, 5-50 parts of benzocyclobutene derivatives containing silicon-oxygen bonds and 10-60 parts of epoxy resin.

[0007] As a preferred embodiment, the molar ratio of the bismaleimide to the benzocyclobutene derivative containing a silicon-oxygen bond is (0.3-5):1.

[0008] As a preferred embodiment, the general structural formula of the bismaleimide is as follows:

[0009]

[0010] R 1 for

[0011]

[0012] One of the formulas 1 and 2, wherein n in both formula 1 and formula 2 is a positive integer of 1-5.

[0013] As a preferred embodiment, the benzocyclobutene derivative containing a silicon-oxygen bond is a benzocyclobutene silicone resin, and its structural formula is as follows:

[0014]

[0015] As a preferred embodiment, the epoxy resin is one or more of bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, bisphenol E epoxy resin, phosphorus-containing epoxy resin, nitrogen-containing epoxy resin, o-cresol epoxy resin, bisphenol A novolac epoxy resin, phenol novolac epoxy resin, cresol novolac epoxy resin, triphenylmethane epoxy resin, tetraphenylethane epoxy resin, biphenyl epoxy resin, naphthalene ring epoxy resin, dicyclopentadiene epoxy resin, isocyanate epoxy resin, aralkyl linear phenolic epoxy resin, alicyclic epoxy resin, glycidyl amine epoxy resin, glycidyl ether epoxy resin, and glycidyl ester epoxy resin.

[0016] As a preferred embodiment, 1-30 parts of a cross-linking auxiliary agent is further included.

[0017] As a preferred solution, the cross-linking auxiliary agent is an active ester.

[0018] As a preferred embodiment, the invention further comprises an initiator, an accelerator and a filler, wherein the weight of the initiator accounts for 0.01-5% of the total weight of the resin composition, and the initiator is dicumyl peroxide; the weight of the accelerator accounts for 0.01-5% of the total weight of the resin composition, and the accelerator is 2-ethyl-4-methylimidazole; the weight of the filler accounts for 0-70% of the total weight of the resin composition, and the filler is silicon dioxide.

[0019] A prepreg is prepared from the modified bismaleimide resin composition.

[0020] A copper foil substrate is prepared from the above-mentioned prepreg.

[0021] Compared with the prior art, the present invention has obvious advantages and beneficial effects. Specifically, it can be seen from the above technical solution that:

[0022] By compounding bismaleimide with a benzocyclobutene derivative containing a silicon-oxygen bond, the benzocyclobutene derivative containing a silicon-oxygen bond will be ring-opened and isomerized into a very active diene under the action of heat, and the isomerized diene will undergo a Diels-Alder addition reaction with bismaleimide. The product after the addition has an extremely high Tg and thermal decomposition temperature, and the silicon-oxygen bond has good flexibility, which can further improve the toughness of the resin and play a certain stress absorption role in the resin composition, thereby maintaining good heat resistance and high-temperature modulus value, while further improving the water absorption rate of the resin system and reducing the CTE in the resin system.

[0023] In order to more clearly illustrate the structural features and effects of the present invention, the present invention is described in detail below in conjunction with specific embodiments: DETAILED DESCRIPTION

[0024] The invention discloses a modified bismaleimide resin composition, which comprises the following components based on 100 parts by weight: 10-80 parts of bismaleimide, 5-50 parts of a benzocyclobutene derivative containing a silicon-oxygen bond, and 10-60 parts of an epoxy resin; wherein the molar ratio of the bismaleimide to the benzocyclobutene derivative containing a silicon-oxygen bond is (0.3-5):1.

[0025] The general structural formula of the bismaleimide is as follows:

[0026]

[0027] R 1 for

[0028]

[0029] One of the formulas 1 and 2, wherein n in both formula 1 and formula 2 is a positive integer of 1-5.

[0030] The benzocyclobutene derivative containing a silicon-oxygen bond is a benzocyclobutene silicone resin, and its structural formula is as follows:

[0031]

[0032] The epoxy resin is one or more of bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, bisphenol E epoxy resin, phosphorus-containing epoxy resin, nitrogen-containing epoxy resin, o-cresol epoxy resin, bisphenol A novolac epoxy resin, phenol novolac epoxy resin, cresol novolac epoxy resin, triphenylmethane epoxy resin, tetraphenylethane epoxy resin, biphenyl epoxy resin, naphthalene ring epoxy resin, dicyclopentadiene epoxy resin, isocyanate epoxy resin, aralkyl linear novolac epoxy resin, alicyclic epoxy resin, glycidyl amine epoxy resin, glycidyl ether epoxy resin, and glycidyl ester epoxy resin.

[0033] And, it further includes 1-30 parts of a crosslinking auxiliary agent, which is an active ester; it also includes an initiator, an accelerator and a filler, the weight of the initiator accounts for 0.01-5% of the total weight of the resin composition, and the initiator is diisopropylbenzene peroxide; the weight of the accelerator accounts for 0.01-5% of the total weight of the resin composition, and the accelerator is 2-ethyl-4-methylimidazole; the weight of the filler accounts for 0-70% of the total weight of the resin composition, and the filler is silicon dioxide.

[0034] The present invention also discloses a semi-cured film, which is prepared from the modified bismaleimide resin composition. The preparation process is as follows: first, the raw material components are mixed according to the components, and are mixed uniformly by stirring at a temperature greater than 200° C., thereby obtaining the modified bismaleimide resin composition. Next, the modified bismaleimide resin composition is placed in an appropriate amount of butanone solvent, and is stirred and mixed uniformly to obtain a glue solution with a solid weight percentage of 65%. The glue solution is impregnated and coated on an E glass fiber cloth of model 7628, and is baked in an oven at 160° C. for 5 minutes to obtain a semi-cured film.

[0035] The present invention also discloses a copper foil substrate, which is prepared from the above-mentioned prepreg; the manufacturing process is as follows: a metal copper foil with a thickness of 18 μm is placed on the upper and lower surfaces of the prepreg, and then placed in a vacuum hot press, and pressed for 4 hours at a pressure of 1.5 MPa and a temperature of 180-220° C. to obtain a laminate. This preparation method is used in the subsequent embodiments.

[0036] The raw materials used in the following examples and comparative examples are shown in Table 1:

[0037]

[0038] Table 1.

[0039] The preparation method of BMI-1 is as follows:

[0040] Add 12.9g (0.1mol) of dichlorodimethylsilane (Shanghai Bangcheng Chemical Co., Ltd.) to 50ml of DMF, and drop 18.9g (0.1mol) of N-(4-hydroxyphenyl) maleimide (Shanghai Tuojing New Materials Technology Co., Ltd.) in a mixture of 50ml of DMF and 7.9g (0.1mol) of pyridine at 0°C. Stir at room temperature for 4h. Add dropwise 34g (0.05mol) of hydroxyl-terminated polysiloxane (Shanghai Zhongyi Chemical Co., Ltd.) in a solution of 50mL of DMF and 7.9g (0.1mol) of pyridine at 0°C. After addition, stir at 40°C for 4h, leave overnight, pour into crushed ice, filter out the solid, wash with dilute sodium bicarbonate solution and water, and vacuum dry the product at 50°C for 10h to obtain yellow-red modified siloxane chain bismaleimide powder BMI-1, which is a mixture and has an average molar mass of 742g / mol. The reaction scheme of BMI-1 is as follows:

[0041]

[0042] The preparation method of BMI-2 is as follows:

[0043] Dichlorodiethylsilane was used to replace the dichlorodimethylsilane in BMI-1, and the remaining preparation steps were the same as those of BMI-1 to obtain a modified siloxane chain bismaleimide powder BMI-2, which was a mixture and had an average molar mass of 798 g / mol. The reaction flow of BMI-2 is as follows:

[0044]

[0045] The preparation method of BMI-3 is as follows:

[0046] Dissolve 10 mmol of dichlorodimethylsilane in 10 ml of DMF, add dropwise a solution of 18.9 g (0.1 mol) of N-(4-hydroxyphenyl)maleimide in 25 ml of DMF and 10 ml of pyridine at -5°C, stir at room temperature for 3 hours under nitrogen, then add dropwise a solution of hydroquinone in 15 ml of DMF and 10 ml of pyridine, react at room temperature for 4 hours to obtain BMI-3. The reaction flow of BMI-3 is as follows:

[0047]

[0048] The raw material ratios of Examples 1-12 and Comparative Examples 1-6 are shown in Table 2:

[0049]

[0050] Table 2 performs performance tests on the above multiple embodiments and comparative examples, and the test results are shown in Table 3:

[0051]

[0052] Table 3

[0053] The above data are analyzed. Examples 3 and 4, and Examples 5 and 6 all use the same raw materials. The difference is that in the reaction systems of Examples 4 and 6, the molar ratio of bismaleimide to the benzocyclobutene derivative containing a silicon-oxygen bond is not in the range of (0.3-5):1. The finished products obtained in Examples 4 and 6 are significantly inferior to those obtained in Examples 3 and 5 in terms of glass transition temperature, thermal decomposition temperature, peel strength, water absorption rate and thermal expansion coefficient. It can be seen that in the reaction system, when the molar ratio of bismaleimide to the benzocyclobutene derivative containing a silicon-oxygen bond is in the range of (0.3-5):1, the performance of the obtained product reaches the best.

[0054] At the same time, Example 1-6 and Example 7-12 are compared. The only difference between Example 7-12 and Example 1-6 is that Example 1-6 uses homemade bismaleimide as a raw material, and Example 7-12 uses commercially available bismaleimide as a raw material. The finished product prepared by Example 7-12 is not much different from the finished product prepared by Example 1-6 in terms of thermal decomposition temperature and glass transition temperature, but has a significant decline in peel strength, water absorption rate and thermal expansion coefficient. It can be seen that the final product obtained by compounding the benzocyclobutene derivative containing a silicon-oxygen bond with BMI-1, BMI-2, and BMI-3 has better performance;

[0055] Moreover, the finished products prepared in Example 10 and Example 12 have the best performance in Examples 7-12, while the finished products prepared in Example 4 and Example 6 have the worst performance in Examples 1-6, presenting a completely opposite result. It is obvious that when the benzocyclobutene derivative containing a silicon-oxygen bond is compounded with BMI-1, BMI-2, and BMI-3 in a molar ratio of (0.3-5):1, the various compounds obtained after the reaction form a synergistic effect in the resin system, further improving the defects of the resin composition, so that its excellent performance can be further optimized;

[0056] Furthermore, it can be clearly seen from Comparative Examples 1-6 that the performance of the finished product obtained by not adding the benzocyclobutene derivative containing silicon-oxygen bonds to the resin system shows a significant decline in all aspects compared with Examples 1-12. Moreover, by comparing Comparative Examples 1-3 and Comparative Examples 4-6, the water absorption rate and thermal expansion coefficient of Comparative Examples 1-3 using homemade bismaleimide are far worse than those of Comparative Examples 4-6 using commercially available bismaleimide. Referring to Examples 1-12, after introducing benzocyclobutene derivative containing silicon-oxygen bonds into the resin system, the product performance of Example 1-6 using homemade bismaleimide is better than that of Example 7-12 using commercially available bismaleimide. It can be seen that the benzocyclobutene derivative containing silicon-oxygen bonds has a greater improvement on BMI-1, BMI-2, and BMI-3.

[0057] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A modified bismaleimide resin composition, characterized in that: The invention comprises the following components based on 100 parts by weight: 10-80 parts of bismaleimide, 5-50 parts of benzocyclobutene derivatives containing silicon oxygen bonds and 10-60 parts of epoxy resin.

2. The modified bismaleimide resin composition according to claim 1, characterized in that: The molar ratio of the bismaleimide to the benzocyclobutene derivative containing a silicon-oxygen bond is (0.3-5):

1.

3. The modified bismaleimide resin composition according to claim 1, characterized in that: The general structural formula of the bismaleimide is as follows: R1 is or One of the formulas 1 and 2, wherein n in both formula 1 and formula 2 is a positive integer of 1-5.

4. The modified bismaleimide resin composition according to claim 1, characterized in that: The benzocyclobutene derivative containing a silicon-oxygen bond is a benzocyclobutene silicone resin, and its structural formula is as follows:

5. The modified bismaleimide resin composition according to claim 1, characterized in that: The epoxy resin is one or more of bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, bisphenol E epoxy resin, phosphorus-containing epoxy resin, nitrogen-containing epoxy resin, o-cresol epoxy resin, bisphenol A novolac epoxy resin, phenol novolac epoxy resin, cresol novolac epoxy resin, triphenylmethane epoxy resin, tetraphenylethane epoxy resin, biphenyl epoxy resin, naphthalene ring epoxy resin, dicyclopentadiene epoxy resin, isocyanate epoxy resin, aralkyl linear novolac epoxy resin, alicyclic epoxy resin, glycidyl amine epoxy resin, glycidyl ether epoxy resin, and glycidyl ester epoxy resin.

6. The modified bismaleimide resin composition according to claim 1, characterized in that: The invention further comprises 1-30 parts of a cross-linking auxiliary agent.

7. The modified bismaleimide resin composition according to claim 6, characterized in that: The cross-linking auxiliary agent is an active ester.

8. The modified bismaleimide resin composition according to claim 1, characterized in that: The invention further comprises an initiator, an accelerator and a filler, wherein the weight of the initiator accounts for 0.01-5% of the total weight of the resin composition, and the initiator is dicumyl peroxide; the weight of the accelerator accounts for 0.01-5% of the total weight of the resin composition, and the accelerator is 2-ethyl-4-methylimidazole; the weight of the filler accounts for 0-70% of the total weight of the resin composition, and the filler is silicon dioxide.

9. A prepreg, characterized in that: The modified bismaleimide resin composition is prepared from any one of claims 1 to 8.

10. A copper foil substrate, characterized in that: Prepared from the prepreg according to claim 9.

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