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

Abstract

Provided are a thermosetting resin composition, and a prepreg, a laminate and a printed circuit board using same. The thermosetting resin composition comprises a resin component comprising a modified cycloolefin copolymer and other unsaturated resins. The modified cycloolefin copolymer is a reaction product of maleic anhydride and a cycloolefin copolymer; the cycloolefin copolymer is a copolymerization product of a monomer A and a monomer B; the monomer A is selected from one of or a combination of at least two of norbornene, cyclopentadiene, dicyclopentadiene, tricyclopentadiene, and (I); and the monomer B is selected from one of or a combination of at least two of C2-C3 olefins and C2-C3 alkynes. The laminate prepared by using the provided thermosetting resin composition has good dielectric properties, peel strength and thermal resistance, and can satisfy the current requirements of properties for printed circuit board substrates in the field of high-frequency and high-speed communications.

Claims

1. A thermosetting resin composition, comprising a resin component, wherein the resin component comprises a modified cycloolefin copolymer, and other unsaturated resins; the modified cycloolefin copolymer is a reaction product of maleic anhydride and a cycloolefin copolymer.

2. The thermosetting resin composition according to claim 1, wherein the cycloolefin copolymer is a copolymerization product of a monomer A and a monomer B, and the monomer A is selected from one or a combination of at least two of norbornene, cyclopentadiene, dicyclopentadiene, tricyclopentadiene and ##STR00005## the monomer B is selected from one or a combination of at least two of C2-C3 olefin and C2-C3 alkyne.

3. The thermosetting resin composition according to claim 1, wherein the resin component comprises 5-30 wt % of the modified cycloolefin copolymer and 70-95 wt % of other unsaturated resins.

4. The thermosetting resin composition according to claim 1, 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 the 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 of 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 a mass of the maleic anhydride accounts for 10-70% of a mass of the cycloolefin copolymer.

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

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

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

16. 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.

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

18. The thermosetting resin composition according to claim 17, wherein the initiator is an azo initiator or a peroxide initiator.

19. 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, an bismaleimide resin, a cyanate resin, an allyl-modified benzoxazine resin, triallyl isocyanurate and triallyl cyanurate.

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

Description

DETAILED DESCRIPTION

[0077] 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 to the present application.

Preparation Example 1

[0078] A maleic anhydride-modified cycloolefin copolymer A-1 is provided, and its preparation steps are described below.

[0079] 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 anhydrous and anoxic treatment 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 standard atmospheric pressures controlled by adding ethylene, reacted at 40° C. for 2 h under this pressure, so as to obtain a cycloolefin copolymer.

[0080] Step 2. On the basis of Step 1, a maleic anhydride monomer with an amount of 10% of a mass of the cycloolefin copolymer obtained in Step 1 was added and reacted for 3 h, ensuring 15% of C═C double bonds remained. Due to the C═C double bonds contained in maleic anhydride, maleic anhydride could react with the double bonds in the cycloolefin copolymer and be grafted to molecular chains of the cycloolefin copolymer. 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 the maleic anhydride-modified cycloolefin copolymer denoted as A-1.

[0081] Using the gel permeation chromatography for detection, it was found that a number average molecular mass M.sub.n was 3510, and a molecular weight distribution index M.sub.W/M.sub.n was 1.52.

Preparation Example 2

[0082] A maleic anhydride-modified cycloolefin copolymer A-2 is provided, and its preparation steps are described below.

[0083] Step 1. Synthesis of a TCPD-ethylene 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 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 by adding ethylene, reacted at 40° C. for 2 h under this pressure, so as to obtain an unmodified unsaturated cycloolefin copolymer.

[0084] Step 2. On the basis of Step 1, a maleic anhydride monomer with an amount of 30% of a mass of the cycloolefin copolymer obtained in Step 1 was added and reacted for 3 h, ensuring 30% of C═C double bonds remained. Due to the C═C double bonds contained in maleic anhydride, maleic anhydride could react with the double bonds in the cycloolefin copolymer and be grafted to molecular chains of the cycloolefin copolymer. 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 the maleic anhydride-modified cycloolefin copolymer denoted as A-2.

[0085] Using the gel permeation chromatography for detection, it was found that a number average molecular mass M.sub.n was 5120, and a molecular weight distribution index M.sub.w/M.sub.n was 1.63.

Preparation Example 3

[0086] A maleic anhydride-modified cycloolefin 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.

[0087] Types and sources of the raw materials used in the above-mentioned examples are as follows:

[0088] (A) Cycloolefin Copolymer

[0089] A-1 Maleic anhydride-modified cycloolefin copolymer (prepared in Preparation Example 1);

[0090] A-2 Maleic anhydride-modified cycloolefin copolymer (prepared in Preparation Example 2);

[0091] A-3 Maleic anhydride-modified cycloolefin copolymer (prepared in Preparation Example 3);

[0092] (B) Other resins

[0093] B-1 Allyl-modified polyphenylene ether resin (Product Model PP501, Taiwan Chain Yee);

[0094] B-2 Polybutadiene (Product Model Nippo Soda B-3000);

[0095] B-3 Styrene-butadiene resin (Product Model Ricon 100);

[0096] B-4 Unmodified unsaturated cycloolefin copolymer (an intermediate product of Preparation Example 2)

[0097] B-5 Saturated cycloolefin copolymer (Product Model TOPAS 6017)

[0098] B-6 Epoxy resin (Product Model E-51 epoxy resin);

[0099] (C) Filler: Spherical silica powder (Product Model SFP-30M, Denka Chemical Industry Co., Ltd.);

[0100] (D) Flame retardant: Phenoxyphosphazene compound (Product Model SPB-100, Japan Otsuka Chemical Co., Ltd.);

[0101] (E) Initiator: Dicumyl peroxide (Shanghai Gaoqiao).

Examples 1-9

[0102] Examples 1-9 each provide a copper clad laminate, and its preparation method is described below.

[0103] (1) Preparation of a Resin Varnish

[0104] 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 liquid with a solid content of 65%.

[0105] (2) Preparation of a Prepreg

[0106] The 2116# fiberglass cloth was used as a reinforcing material, infiltrated with the prepared resin liquid, baked in an oven at 155° C. for 3 min, and prepared into the prepreg (bonding sheet).

[0107] (3) Preparation of a Copper Clad Laminate

[0108] The prepreg was cut according to a certain size, and 6 prepregs were neatly stacked, covered with electrolytic copper foils of 35 μm thickness on both sides, and cured in a vacuum press with pressure and heat, 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

[0109] A copper clad laminate is provided, which is different from Example 1 in that the maleic anhydride-modified cycloolefin copolymer A-1 was replaced with an unmodified unsaturated cycloolefin copolymer B-4.

Comparative Example 2

[0110] 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

[0111] 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.

[0112] 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 TABLE 1 Raw material/ Example Example Example Example Example Example Example Performance 1 2 3 4 5 6 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 201 218 215 210 200 220 225 transition temperature Tg (DSC)/° C. Flammability V-0 V-0 V-0 V-0 V-0 V-0 V-0 (UL94) Thermal >60 >60 >60 >60 >60 >60 >60 delamination time T-288/min Peel strength 0.92 1.08 1.02 1.05 1.01 1.03 1.09 (N/mm) Thermal 431 427 423 420 423 421 435 decomposition temperature Td5 % (TGA, ° C.) Water 0.018 0.08 0.2 0.12 0.10 0.09 0.09 absorption rate (%) Dielectric 3.54 3.59 3.75 3.66 3.62 3.61 3.50 Constant Dk (SDPR 10 GHz) Dielectric 0.0026 0.0024 0.003 0.0025 0.022 0.0023 0.0021 dissipation Df (SDPR 10 GHz)

TABLE-US-00002 TABLE 2 Raw material/ Comparative Comparative Comparative Performance Example 8 Example 9 Example 1 Example 2 Example 3 A-1 / / / 15 / A-2 21 8 / 15 15 A-3 / / / / 15 B-1 / / 68 / / B-2 / / / / / B-3 / 10 / / / B-4 17 20 20 / 28 B-5 / / / / / B-6 / / / 28 / C 50 50 / 30 30 D 10 10 10 10 10 E 2 2 2 2 2 Glass transition 201 217 217 180 202 temperature Tg (DSC)/° C. Flammability V-0 V-0 V-0 V-0 V-0 (UL94) Thermal >60 >60 >60 30 40 delamination time T-288/min Peel strength 0.92 0.97 0.84 1.01 0.88 (N/mm) Thermal 431 421 410 373 415 decomposition temperature Td5 % (TGA, ° C.) Water 0.018 0.20 0.15 0.34 0.12 absorption rate (%) Dielectric 3.54 3.58 3.54 3.9 3.75 Constant Dk (SDPR 10 GHz) Dielectric 0.0026 0.0025 0.0023 0.0043 0.0033 dissipation Df (SDPR 10 GHz)

[0113] Test methods for the above performance are as follows:

[0114] (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;

[0115] (2) Flammability: measured according to the flammability method specified in UL94;

[0116] (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;

[0117] (4) Peel strength: measured according to IPC-TM-650 2.4.8 method;

[0118] (5) Thermal decomposition temperature (T.sub.d5%): measured by using the thermogravimetric nnalysis (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;

[0119] (6) Water absorption rate: measured according to the water absorption test method specified in IPC-TM-650 2.6.2.1;

[0120] (7) Dielectric constant (D.sub.k) and dielectric dissipation factor (D.sub.f): measured according to the Split Post Dielectric Resonator (SPDR) method;

[0121] 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 200-225° C., the temperature of 420-435° C. corresponding to 5% thermal weight loss, the peel strength reaching 0.91-1.09 N/mm, the thermal delamination time reaching more than or equal to 60 min, the dielectric constant D.sub.k (10 GHz) of 3.5-3.75, the dielectric dissipation factor D.sub.f (10 GHz) of 0.0021-0.003, and the water absorption rate of 0.018-0.2%, and had good heat resistance, dielectric properties, high peel strength, low water absorption rate, which was suitable for high-frequency and high-speed communication fields.

[0122] In the present application, a saturated resin can also be added. For example, an appropriate amount of saturated COC was added in Example 5 due to its good dielectric properties, but the prepared copper clad laminate had low Tg and peel strength.

[0123] Among the examples, compared with Example 1, Comparative Example 1 used the unmodified unsaturated COC to replace the maleic anhydride-modified COC. Since the unmodified unsaturated COC had no polar group, the peel strength of the prepared copper clad laminate was poor.

[0124] Compared with Example 3, since Comparative Example 2 used the epoxy resin to replace the unsaturated styrene-butadiene resin, the prepared copper clad laminate had very poor dielectric properties and heat resistance, which could not satisfy high-frequency applications.

[0125] Compared with Example 4, Comparative Example 3 only used the commercial non-modified cycloolefin copolymer TOPAS 6017 without other unsaturated resins. Since there is no reactive C═C, a three-dimensional cross-linked network cannot be formed. Thus the copper clad laminate using the copolymer had poor heat resistant properties such as Tg and solder dipping resistance, and poor peel strength.

[0126] 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 technical scope and the disclosure scope of the present application.