THERMOSETTING RESIN COMPOSITION AND PREPREG, LAMINATE AND PRINTED CIRCUIT BOARD USING SAME

Abstract

Provided are a thermosetting resin composition and a prepreg, laminate and printed circuit board using same. The thermosetting resin composition comprises a resin component, the resin component comprising a modified cyclic olefin copolymer having a structure as shown in formula I and another unsaturated resin. By introducing a methacrylate end group having a certain polarity into a cyclic olefin copolymer, a modified cyclic olefin copolymer is formed. The modified cyclic olefin copolymer can form a thermosetting material by means of cross-linking with itself or another unsaturated resin, whereby the bonding property can be significantly improved while retaining the excellent dielectric properties of the cyclic olefin copolymer itself. The laminate prepared using the thermosetting resin composition has good dielectric properties, a good peel strength and a good heat resistance, and can meet all the performance requirements for printed circuit board substrates in the current high-frequency and high-speed communication field.

Claims

1. A thermosetting resin composition, comprising a resin component, wherein the resin component comprises a modified cycloolefin copolymer having a structure as shown in formula I, and other unsaturated resins; ##STR00020## wherein A is selected from one or at least two of ##STR00021## ##STR00022## ##STR00023## ##STR00024## ##STR00025## ##STR00026## ##STR00027## and ##STR00028## B is selected from one or at least two of ##STR00029## ##STR00030## ##STR00031## ##STR00032## ##STR00033## ##STR00034## n is an integer of 0-100, and * represents a linkage site of the group.

2. The thermosetting resin composition according to claim 1, wherein n is an integer of 10-80 in formula I.

3. The thermosetting resin composition according to claim 1 or 2, wherein the resin component comprises 5-30 wt% of the modified cycloolefin copolymer having the structure as shown in formula I and 70-95 wt% of other unsaturated resins.

4. The thermosetting resin composition according to any one of claims 1-3, wherein based on that a total part by weight of the thermosetting resin composition is 100 parts, the thermosetting resin composition comprises 10-90 parts of a resin component, 0-60 parts of a filler and 5-20 parts of a flame retardant.

5. A prepreg, comprising a reinforcing material, and the thermosetting resin composition according to claim 1 which is adhered to the reinforcing material after impregnating and drying.

6. A resin film, which is prepared by semi-curing the thermosetting resin composition according to claim 1 by baking and heating.

7. A resin-coated copper foil, which is prepared by coating the thermosetting resin composition according to claim 1 on a copper foil, and heating the same for a semi-cured state.

8. A laminate, comprising one or at least two stacked prepregs according to claim 5.

9. A metal foil clad laminate, comprising one or at least two stacked prepregs according to claim 5, and a metal foil covered on one or two sides of the one prepreg or the stacked prepregs.

10. A printed circuit board, which is prepared by removing part of the metal foil on the surface of the metal foil clad laminate according to claim 9 to form a circuit.

11. The thermosetting resin composition according to claim 1, wherein a number average molecular mass of the modified cycloolefin copolymer is 1000-150000.

12. The thermosetting resin composition according to claim 1, wherein in Unit A and Unit B of the modified cycloolefin copolymer, a number of units containing carbon-carbon double bonds accounts for 10-70% of a total number of Unit A and Unit B.

13. The thermosetting resin composition according to claim 1, wherein the other unsaturated resins are selected from one or a combination of at least two of an unmodified unsaturated cycloolefin copolymer, a polyphenylene ether resin containing double bonds as an end group, a modified or unmodified polybutadiene resin, a modified or unmodified polyisoprene resin, a bismaleimide resin, a cyanate resin, an allyl-modified benzoxazine resin, triallyl isocyanurate and triallyl cyanurate.

14. The thermosetting resin composition according to claim 1, wherein the other unsaturated resins comprise an unmodified unsaturated cycloolefin copolymer which accounts for 40-70% of a mass of the resin component.

15. The thermosetting resin composition according to claim 1, wherein the resin component further comprises a saturated resin.

16. The thermosetting resin composition according to claim 4, wherein the filler is an inorganic filler and/or an organic filler.

17. The thermosetting resin composition according to claim 4, wherein the flame retardant is selected from a bromine-containing flame retardant or a halogen-free flame retardant.

18. The thermosetting resin composition according to claim 17, wherein the halogen-free flame retardant is selected from one or a combination of at least two of a phosphate salt flame retardant, a phosphate flame retardant and a phosphazene flame retardant.

19. The thermosetting resin composition according to claim 1, wherein the thermosetting resin composition further comprises 0.1-3 parts of an initiator.

20. The thermosetting resin composition according to claim 19, wherein the initiator is an azo initiator or a peroxide initiator.

Description

DETAILED DESCRIPTION

[0070] Technical solutions of the present application are further described below in conjunction with specific embodiments. Those skilled in the art should understand that the embodiments described herein are merely used for a better understanding of the present application and should not be construed as specific limitations on the present application.

Preparation Example 1

[0071] A modified norbornene-ethylene copolymer A-1 is provided, and its preparation steps are described below.

[0072] Step 1. Synthesis of an ethylene-norbornene copolymer: a 500 mL polymerization reactor dried by heating was subjected to vacuum and purged with nitrogen twice, and then subjected to vacuum again and injected with ethylene; then, 4 mL of a toluene solution of methylaluminoxane (1.5 mmol/mL), 66 mL of toluene with water and oxygen removed and 20 mL of a toluene solution of norbornene (2 mmol/mL) were added sequentially, injected with ethylene of 3 atmospheric pressures to saturation under mechanical stirring and, with 3 atmospheric pressures controlled through adding ethylene, reacted at 40° C. for 2 h under this pressure, and then added with an end-capping reagent of 5-norbomene-2-methanol (CAS: 13080-90-5) and reacted for 2 h.

[0073] Step 2. On the basis of Step 1 and with 3 standard atmospheric pressures controlled, hydrogen was injected, and the hydrogenation process was performed for 30 min, controlling a hydrogen amount and an addition time, and ensuring 15% of C=C double bonds remained. After the reaction was completed, the reaction liquid was poured into anhydrous methanol, and a large amount of white polymer was precipitated. The product obtained by filtration was washed with acetone for 3 times, then put into a vacuum oven and dried at 40° C. for 12 hours.

[0074] Step 3. the solid prepared in Step 2 was dissolved in a toluene solvent, methacryloyl chloride was slowly added dropwise in an ice bath (-5° C. to 5° C.) condition, and meanwhile, 2 g of triethylamine was added in three separate rounds as an acid binding agent (also as a catalyst), and the addition process of the methacryloyl chloride reagent was controlled at 30 min-60 min. After the addition, the mixture was then reacted for 5 h, the reaction liquid was poured into anhydrous methanol, and a large amount of white polymer was precipitated. The product obtained by filtration was washed with acetone for 3 times, then put into a vacuum oven and dried at 40° C. for 12 hours, so as to obtain a modified COC with methacrylate end groups, which was denoted as A-1.

[0075] Using the gel permeation chromatography for detection, it was found that a number average molecular mass M.sub.n was 3150, and a molecular weight distribution index M.sub.w/M.sub.n was 1.85.

Preparation Example 2

[0076] A modified TCPD-ethylene copolymer A-2 is provided, and its preparation steps are described below.

[0077] Step 1. Synthesis of an ethylene-tricyclopentadiene copolymer: a 500 mL polymerization reactor dried by heating was subjected to vacuum and purged with nitrogen twice, and then subjected to vacuum again and injected with ethylene; then, 4 mL of a toluene solution of methylaluminoxane (1.5 mmol/mL), 66 mL of toluene with anhydrous and anoxic treatment and 20 mL of a toluene solution of tricyclopentadiene (TCPD) (2 mmol/mL) were added sequentially, injected with ethylene of 3 atmospheric pressures to saturation under mechanical stirring and, with 3 standard atmospheric pressures controlled through adding ethylene, reacted at 40° C. for 2 h under this pressure, and then added with an end-capping reagent of 5-norbomene-2-methanol (CAS: 13080-90-5) and reacted for 2 h.

[0078] Step 2. On the basis of Step 1 and with 3 standard atmospheric pressures controlled, hydrogen was injected, and the hydrogenation process was performed for 30 min, controlling a hydrogen amount and an addition time, and ensuring 30% of C═C double bonds remained. After the reaction was completed, the reaction liquid was poured into anhydrous methanol, and a large amount of white polymer was precipitated. The product obtained by filtration was washed with acetone for 3 times, then put into a vacuum oven and dried at 40° C. for 12 hours, so as to obtain an unmodified unsaturated cycloolefin copolymer denoted as B-4.

[0079] Step 3. the solid prepared in Step 2 was dissolved in a toluene solvent, methacryloyl chloride was slowly added dropwise in an ice bath (-5° C. to 5° C.) condition, and meanwhile, 2 g of triethylamine was added in three separate rounds as an acid binding agent (also as a catalyst), and the addition process of the methacryloyl chloride reagent was controlled at 30 min-60 min. After the addition, the mixture was then reacted for 5 h, the reaction liquid was poured into anhydrous methanol, and a large amount of white polymer was precipitated. The product obtained by filtration was washed with acetone for 3 times, then put into a vacuum oven and dried at 40° C. for 12 hours, so as to obtain a modified COC with methacrylate end groups, which was denoted as A-2.

[0080] Through detection, it was found that a number average molecular mass M.sub.n was 6310, and a molecular weight distribution index M.sub.w/M.sub.n was 2.1.

Preparation Example 3

[0081] A modified TCPD-ethylene copolymer A-3 is provided, and its preparation method differs from Preparation Example 2 in that hydrogenation was performed in Step (2) until the content of carbon-carbon double bonds was 0.

[0082] Types and sources of the raw materials used in the examples below are as follows: [0083] (A) Cycloolefin Copolymer [0084] A-1 Methyl methacrylate-modified norbomene-ethylene copolymer (prepared in Preparation Example 1); [0085] A-2 Methyl methacrylate-modified TCPD-ethylene copolymer (prepared in Preparation Example 2); [0086] A-3 Methyl methacrylate-modified TCPD-ethylene copolymer (prepared in Preparation Example 3); [0087] (B) Other resins [0088] B-1 Allyl-modified polyphenylene ether resin (Product Model PP501, Taiwan Chain Yee); [0089] B-2 Polybutadiene (Product Model Japan Caoda B-3000); [0090] B-3 Styrene-butadiene resin (Product Model Ricon 100); [0091] B-4 Unmodified unsaturated cycloolefin copolymer (an intermediate product of Preparation Example 2) [0092] B-5 Saturated cycloolefin copolymer (Product Model TOPAS 6017) [0093] B-6 Epoxy resin (E51 epoxy resin); [0094] (C) Filler: Spherical silica powder (Product Model SFP-30M, Denka Chemical Industry Co., Ltd.); [0095] (D) Flame retardant: Phenoxyphosphazene compound (Product Model SPB-100, Japan Otsuka Chemical Co., Ltd.); [0096] (E) Initiator: Dicumyl peroxide (Shanghai Gaoqiao).

Examples 1-9

[0097] Examples 1-9 each provide a copper clad laminate, and its preparation method is described below.

Preparation of a Resin Varnish

[0098] Component A of a modified cycloolefin copolymer, Component B of other unsaturated resins except a modified cycloolefin copolymer, Component C of a filler, Component D of a flame retardant, and Component E of an initiator were added in a solvent of toluene with a proportion, and mixed uniformly, so as to obtain a resin varnish with a solid content of 65%.

Preparation of a Prepreg

[0099] The 2116# fiberglass cloth was used as a reinforcing material, impregnated with the prepared resin varnish, baked in an oven at 155° C. for 3 min, and prepared into the prepreg (bonding sheet).

Preparation of a Copper Clad Laminate

[0100] The prepreg was cut according to a certain size, and 6 prepregs were neatly stacked, covered with electrolytic copper foils of 35 .Math.m thickness on both sides, and heated and cured in a vacuum press, in which hot pressing conditions for preparing the copper clad laminate included: a temperature of 210° C., a pressure of 25 kg/cm.sup.2, and a pressing time of 90 min.

Comparative Example 1

[0101] A copper clad laminate is provided, which is different from Example 3 in that the modified cycloolefin copolymer A-1 was replaced with an unmodified unsaturated cycloolefin copolymer B-4.

Comparative Example 2

[0102] A copper clad laminate is provided, which is different from Example 3 in that the styrene-butadiene resin B-3 was replaced with an epoxy resin B-6.

Comparative Example 3

[0103] A copper-clad laminate is provided, which is different from Example 4 in that the unmodified unsaturated cycloolefin copolymer B-4 was replaced with a saturated cycloolefin copolymer B-5.

[0104] Types and amount (part by weight) of the raw materials used in Examples 1-9 and Comparative Examples 1-3 and performance data of the obtained copper clad laminates are shown in Table 1 and Table 2 below:

TABLE-US-00001 Raw material /Performance Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 A-1 20 / 15 / / 17 / A-2 / 17 15 15 17 / 17 A-3 / / / 15 / / / B-1 68 / / / 17 / / B-2 / 41 / / / 11 / B-3 / / 28 / / / / B-4 / / / 28 / 30 41 B-5 / / / / 24 / / B-6 / / / / / / / C / 30 30 30 30 30 30 D 10 10 10 10 10 10 10 E 2 2 2 2 2 2 2 Glass transition temperature Tg (DSC)/°C 203 217 214 211 201 221 224 Flammability (UL94) V-0 V-0 V-0 V-0 V-0 V-0 V-0 Thermal delamination time T-288/min >60 >60 >60 >60 >60 >60 >60 Peel strength (N/mm) 0.94 1.07 1.03 1.03 1.02 1.01 1.09 Thermal 434 428 421 421 421 422 431 Decomposition temperature Td5% (TGA, °C) Water absorption rate (%) 0.016 0.07 0.11 0.11 0.10 0.09 0.07 Dielectric constant Dk (SDPR 10 GHz) 3.51 3.58 3.61 3.65 3.61 3.61 3.50 Dielectric dissipation Df (SDPR 10 GHz) 0.0025 0.0025 0.0026 0.0025 0.022 0.0023 0.0021

TABLE-US-00002 Raw material/ Performance Example 8 Example 9 Comparative Example 1 Comparative Example 2 Comparative Example 3 A-1 / / / 15 / A-2 21 8 / 15 15 A-3 / / / / 15 B-1 / 10 68 / / B-2 / / / / / B-3 / / / / / B-4 17 20 20 / / B-5 / / / / 28 B-6 / / / 28 C 50 50 / 30 30 D 10 10 10 10 10 E 2 2 2 2 2 Glass transition temperature Tg (DSC)/°C 201 218 211 181 191 Flammability (UL94) V-0 V-0 V-0 V-0 V-0 Thermal delamination time T-288/min >60 >60 >60 30 45 Peel strength (N/mm) 1.03 0.99 0.74 1.00 0.97 Thermal decomposition temperature Td5% (TGA, °C) 431 421 411 371 401 Water absorption rate (%) 0.018 0.21 0.14 0.35 0.17 Dielectric constant Dk (SDPR 10 GHz) 3.55 3.57 3.58 3.9 3.55 Dielectric dissipation Df (SDPR 10 0.0025 0.0024 0.0027 0.0045 0.0024 GHz)

[0105] Test methods for the above performance are as follows: [0106] (1) Glass transition temperature (T.sub.g): measured by using DSC test according to the DSC test method specified in IPC-TM-650 2.4.24; [0107] (2) Flammability: measured according to the flammability method specified in UL94; [0108] (3) Thermal delamination time measured by using a thermomechanical analyzer (TMA) instrument according to the T288 test method specified in IPC-TM-650 2.4.24.1; [0109] (4) Peel strength: measured according to IPC-TM-650 2.4.8 method; [0110] (5) Thermal decomposition temperature (T.sub.d5%): measured by using the thermogravimetric analysis (TGA) test according to the TGA test method specified in IPC-TM-650 2.4.24.6, and taking a temperature corresponding to 5% thermal weight loss as the thermal decomposition temperature; [0111] (6) Water absorption rate: measured according to the water absorption test method specified in IPC-TM-650 2.6.2.1; [0112] (7) Dielectric constant (D.sub.k) and dielectric dissipation factor (D.sub.f): measured according to the Split Post Dielectric Resonator (SPDR) method;

[0113] From the test results in Table 1 and Table 2, it can be seen that the copper clad laminate prepared by using the thermosetting resin composition provided in the present application had the glass transition temperature reaching 201-224° C., the temperature of 421-434° C. corresponding to 5% thermal weight loss, the peel strength reaching 0.92-1.09 N/mm, the thermal delamination time reaching more than or equal to 60 min, the dielectric constant D.sub.k (10 GHz) of 3.50-3.65, the dielectric dissipation factor D.sub.f (10 GHz) of 0.0021-0.0026, and the water absorption rate of 0.016-0.21%, and had good heat resistance, good dielectric properties, high peel strength, low water absorption rate, which was suitable for the high-frequency and high-speed communication field.

[0114] Among the examples, compared with Example 1, Comparative Example 1 used the unmodified unsaturated COC to replace the methacrylate-modified COC. Since the unmodified unsaturated COC had no polar group, the copper clad laminate using the same had poor peel strength.

[0115] Compared with Example 3, since Comparative Example 2 used the epoxy resin to replace the unsaturated styrene-butadiene resin, the dielectric properties of the prepared copper clad laminate deteriorated sharply, which could not satisfy high-frequency applications.

[0116] Compared with Example 4, Comparative Example 3 only used the commercial unmodified cycloolefin copolymer TOPAS 6017 without other unsaturated resins. Since there was no reactive C═C, a three-dimensional cross-linked network could not be formed. Therefore, the copper clad laminate using the copolymer had poor heat resistant properties such as Tg and solder dipping resistance.

[0117] The applicant has stated that although the specific embodiments of the present application is described above, the protection scope of the present application is not limited to the embodiments, and it should be apparent to those skilled in the art that variations or replacements, which are obvious for those skilled in the art without departing from the technical scope disclosed in the present application, all fall within the protection scope and the disclosure scope of the present application.