Method of Manufacturing Cured Phosphorus-Containing Flame-Retardant Epoxy Composite

Abstract

A phosphorus-containing polyester composite and method of manufacturing the same is related to the field of compound formulation. The composite is prepared by condensation under certain conditions of (A) a poly-functional phosphorus-containing aromatic hydroxy compound; (B) a difunctional aromatic acryl chloride compound and (C) a monofunctional aromatic phenol compound used as a blocking agent. The composite is used as a curing agent for epoxy. The phosphorus-containing polyester composite is reacted with the epoxy group of the epoxy to obtain non-halogen and flame-retardant cured composite being environment friendly and having low dielectric, low dielectric loss factor and high heat resistance. It can be used in an integrated circuit board and used as a semiconductor packaging material.

Claims

1. A method for preparing a cured phosphorus-containing flame-retardant epoxy composite, comprising: using the low-dielectric phosphorus-containing polyester composite independently or in combination with a conventional epoxy curing agent to react with epoxy under a high temperature so as to produce the cured phosphorus-containing flame-retardant epoxy composite, wherein the resulting flame-retardant epoxy composite is used as a base resin of a printed circuit board and a semiconductor packaging material.

2. The method of claim 1, wherein the mass content of phosphorus is in the range of 0.5-10%.

3. The method of claim 1, wherein the conventional epoxy curing agent is selected from phenol-formaldehydenovolac, o-cresol-formaldehydenovalac, bisphenol A-formaldehydenovolac, dicyandiamide, methylenedianiline and diamihodiphenylsulfone, or a combination thereof.

4. The method of claim 1, wherein the epoxy is selected from bisphenol A epoxy, bisphenol F epoxy, bisphenol S epoxy, dihydroxy diphenyl epoxy phenol novolac epoxy, o-cresol novolac epoxy, bisphenol A novolac epoxy, α-naphthol novolac epoxy, β-naphthol novolac epoxy, epoxy of copolymer of dicyclopentadiene and phenol, or a combination thereof.

5. The method of claim 1, wherein the method for preparing the cured phosphorus-containing flame-retardant epoxy composite is conducted under the presence of a curing accelerator.

6. The method of claim 5, wherein based on the total weight of epoxy and curing agent, the weight of the curing accelerator is in the range of 0.01-2.5%.

7. The method of claim 5, wherein the curing accelerator is one selected from 2-methylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 1 -benzyl-2-methylimidazole, 2-heptadecyl-1H-imidazole, 2-undecyl-1H-imidazole, triphenylphosphine, tributyl phosphine, trimethyl phosphate, triethyl phosphate, or a combination thereof.

Description

DETAILED DESCRIPTION

[0045] In order to make the description of the present invention more detailed and more comprehensive, various aspects and embodiments of the present invention are described below illustratively. However, these illustrated aspects and embodiments are not the only way for implementing or using the embodiments of the present invention. The embodiments disclosed hereinafter may be combined with or replaced by each other under beneficial situations, and alternatively other embodiments may be appended to an embodiment, without any further statement or illustration. In the following description, many specific details are illustrated so that readers can understand the following embodiments completely. However, the embodiments of the present invention may also be implemented without these specific details.

[0046] The present invention can be understood by referring to the following embodiments, and the following embodiments are only used for illustration, without limiting the range of the present invention.

1. Preparation Method of a Phosphorus-Containing Polyester Composite

Synthesis Example 1

[0047] 520 g bisphenol A, 324 g formaldehyde aqueous solution (with a mass concentration of 37%) and 24 g sodium hydroxide are added into a reaction kettle, and then stirring starts and the temperature is raised to 40° C. for 3 hours. Thereafter the temperature is increased to 65° C. for 3 hours, and then 1480 g n-butanol is added and refluxed for 12 hours. Then the material temperature is decreased to 55-60° C., and reduced pressure distillation is performed to remove about 1000 g n-butanol, so as to obtain an intermediate.

[0048] 1080 g DOPO (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) is added into the intermediate, and the material temperature is increased gradually from 80° C. to 180° C. in 2 hours and a reduced pressure is applied to the system at 120° C. to ensure that the n-butanol is discharged from the system in time. The material temperature is kept at 180° C. for 1 hour and then is decreased to 130° C., and the final product is pulled out to obtain a phosphorus phenolic resin P-1.

Synthesis Example 2

[0049] 490 g bisphenol F, 324 g formaldehyde aqueous solution (with a mass concentration of 37%) and 24 g sodium hydroxide are added into a reaction kettle, and then stirring starts and the temperature is raised to 40° C. for 3 hours. Thereafter the temperature is increased to 65° C. for 3 hours, and then 1480 g n-butanol is added and refluxed for 12 hours. Then the material temperature is decreased to 55-60° C., and reduced pressure distillation is performed to remove about 1000 g n-butanol, so as to obtain an intermediate.

[0050] 1080 g DOPO (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) is added into the intermediate, and the material temperature is increased gradually from 80° C. to 180° C. in 2 hours, and a reduced pressure applied to the system at 120° C. to ensure that the n-butanol is discharged from the system in time. The material temperature is kept at 180° C. for 1 h and then is decreased to 130° C., and the final product is pulled out to obtain a phosphorus phenolic resin P-2.

Synthesis Example 3

[0051] 372 g dihydroxy diphenyl, 324 g formaldehyde aqueous solution (with a mass concentration of 37%) and 24 g sodium hydroxide are added into a reaction kettle, and then stirring starts and the temperature is raised to 40° C. for 3 hours. Thereafter the temperature is increased to 65° C. for 3 hours, and then 1480 g n-butanol is added and refluxed for 12 hours. Then the material temperature is decreased to 55-60° C., and reduced pressure distillation is performed to remove about 1000 g n-butanol, so as to obtain an intermediate.

[0052] 1080 g DOPO (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) is added into the intermediate, and the material temperature is increased gradually from 80° C. to 180° C. in 2 hours, and a reduced pressure is applied to the system at 120° C. to ensure that the n-butanol is discharged from the system in time. The material temperature is kept at 180° C. for 1hour and then is decreased to 130° C., and the final product is pulled out to obtain a phosphorus phenolic resin P-3.

Synthesis Example 4

[0053] 542 g bisphenol F, 324 g formaldehyde aqueous solution (with a mass concentration of 37%) and 24 g sodium hydroxide are added into a reaction kettle, then stirring is started and the temperature is heated to 40° C. for 3 hours. Thereafter the temperature is increased to 65° C. for 3 hours, and then 1480 g n-butanol is added and refluxed for 12 hours. Then the material temperature is decreased to 55-60° C., and reduced pressure distillation is performed to remove about 1000 g n-butanol, so as to obtain an intermediate.

[0054] 1080 g DOPO (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) is added into the intermediate, and the material temperature is increased gradually from 80° C. to 180° C. in 2 hours, and a reduced pressure is applied to the system at 120° C. to ensure that the n-butanol is discharged from the system in time. The material temperature is kept at 180° C. for 1 h and then is decreased to 130° C., and the final product is pulled out to obtain a phosphorus phenolic resin P-4.

Synthesis Example 5

[0055] 372 g dicyclopentadiene phenol resin (Taiwan K.L. CHEMICALS K-DPP-85; softening point of 85° C.) 324 g formaldehyde aqueous solution (with a mass concentration of 37%) and 24 g sodium hydroxide are added into a reaction kettle, and then stirring starts, and the temperature is raised to 40° C. for 3 hours. Thereafter the temperature is increased to 65° C. for 3 hours, and then 1480 g n-butanol is added and refluxed for 12 hours. Then the material temperature is decreased to 55-60° C., and reduced pressure distillation is performed to remove about 1000 g n-butanol, so as to obtain an intermediate.

[0056] 1080 g DOPO (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) is added into the intermediate, and the material temperature is increased gradually from 80° C. to 180° C. in 2 hours, and a reduced pressure is applied to the system at 120° C. to ensure that the n-butanol is discharged from the system in time. The material temperature is kept at 180° C. for 1 hour and then is decreased to 130° C., and the final product is pulled out to obtain a phosphorus phenolic resin P-5.

Synthesis Example 6-13

[0057] The phosphorus phenolic resin and monofunctional aromatic phenol compound are dissolved in toluene, and then the solution of difunctional aromatic acryl chloride compound pre-dissolved in toluene is added, and then the temperature is increased to 80° C. under stirring. Thereafter a potassium hydroxide aqueous solution is added dropwise and reacted under 60° C. for 3 hours. After the reaction is completed, the solution stands for liquid separation, the lower brine layer is discharged and the upper layer is washed with water for three times and then the water layer is discharged to obtain a resin solution. The resin solution is dried at 80° C., and the dried resin is dissolved in the toluene to obtain a final resin solution. The detailed ratios of raw materials are as shown in table 1.

Synthesis Example 14-15

[0058] The dicyclopentadiene phenol resin (Taiwan K.L. CHEMICALS K-DPP-85; softening point at 85° C.) (8 eq) and monofunctional aromatic phenol compound are dissolved in toluene, and then the solution of difunctional aromatic acryl chloride compound pre-dissolved in toluene is added, and then the temperature is increased to 80° C. under stirring. Thereafter a potassium hydroxide aqueous solution is added dropwise and reacted under 60° C. for 3 hours. After the reaction is completed, the solution stands for liquid separation, the lower brine layer is discharged and the upper layer is washed with water for three times and then the water layer is discharged to obtain a resin solution. The resin solution is dried at 80° C., and the dried resin is dissolved in the toluene to obtain a final resin solution. The detailed ratios of raw materials are as shown in table 1.

TABLE-US-00001 TABLE 1 Item Number Synthesis Synthesis Synthesis Synthesis Synthesis Exampe 6 Example 7 Example 8 Example 9 Example 10 Product Name B-1 B-2 B-3 B-4 B-5 difunctional isophthaloyl 200 200 100 200 acryl dichloride chloride paraphthaloyi 100 100 compound chloride Phenolic -naphthol 25 25 25 25 compound o-phenylphenol 35 Phenolic phosphorus 420 resin phenolic resin P-1 phosphorus phenolic 400 resin P-2 phosphorus phenolic 350 resin P-3 phosphorus phenolic 430 resin P-4 phosphorus phenolic 380 resin P-5 Item Number Synthesis Synthesis Synthesis Synthesis Synthesis Example Example Example Example Example 11 12 13 14 15 Product Name B-6 B-7 B-8 C-1 C-2 difunctional isophthaloyl 100 200 100 200 200 acryl dichlonde chloride paraphtnaloyl 100 100 compound chloride phenolic -naphthol 25 25 25 compound o-phenylphenol 35 phenol 20 phenolic phosphorus 380 resin phenolic resin P-5 Compound (A-3) 300 Compound (A-4) 320 dicyclopentadiene 300 phenol resin K-DPP-85 dicyclopentadiene 300 phenol resin K-DPP-85

[0059] 2. Testing Results of Phosphorus-Containing Polyester Composite Applied in Copper Converted Laminate

Embodiments 1-8

[0060] Phosphorus-containing polyester composites (from B-1 to B-8), a conventional curing agent, bisphenol A novolac epoxy resin (BNE), o-cresol formaldehyde novolac epoxy resin (CNE) and phenol novolac epoxy (PNE) are mixed uniformly according to the weight ratios shown in table 2, with aluminium hydroxide, silica and imidazole-type curing accelerator in appropriate amount of solvent, then a glass fiber cloth is impregnated with the mixture by using a small-scale impregnation machine, the impregnated glass fiber cloth is heated at 170° C. for 150 seconds, and then cut and cured in a small-scale thermocompressor at 25 kg/cm.sup.2 under a temperature of 185° C. for 2 hours to obtain the non-halogen copper covered laminate.

Comparative Embodiments 1-2

[0061] Polyester composites (from C-1 to C-2), bisphenol A novolac epoxy resin (BNE), o-cresol formaldehyde novolac epoxy resin (CNE) and phenol novolac epoxy (PNE) are mixed uniformly according to the weight ratios shown in table 2, with aluminium hydroxide, silica, imidazole-type curing accelerator and a phosphate flame retardant PX-200 (Japan bus company) in appropriate amount of solvent, then a glass fiber cloth is impregnated with the mixture by using a small-scale impregnation machine, the impregnated glass fiber cloth is heated at 170° C. for 150 seconds, and then cut and cured in a small-scale thermocompressor at 25 kg/cm.sup.2 under a temperature of 185° C. for 2 hours to obtain the non-halogen copper covered laminate.

[0062] 1. Gelling Time of Novolac (Sec):

[0063] 0.3 ml novolac resin is placed on a heating plate of 170° C. to measure the gelling time thereof.

[0064] 2. Glass-Transition Temperature (° C.)

[0065] The used temperature rising rate=20° C./min, as measured by a differential scanning calorimeter (DSC).

[0066] 3. Flame Retardancy:

[0067] The test piece is cut into a rectangle of 0.5 in×4.7 in, then fired for 10 seconds with a blue flame having a flame height of 2 cm, and then the flame is removed, wherein the test piece is fired twice to record the automatic quench time after the flame is removed.

[0068] 4. Water Absorption (%):

[0069] The test piece is heated in a pressure cooker of 2 atm at 120° C. for 30 min.

[0070] 5. Dielectric Loss (1 GHz):

[0071] The test piece is cut into a square of 5 cm×5 cm, plate thicknesses at three positions of the plate is measured, and then the test piece is clamped into a dielectric analyzer to measure the dielectric loss and then take the mean of the measured values.

[0072] 6. Dielectric Constant (1 GHz):

[0073] The etched substrate is cut into a square test piece of 5 cm.sup.2, baked for 2 hours in an oven at 105° C., taken out and then is tested by a plate thickness tester to obtain the plate thicknesses at three positions thereon. Then the test piece is clamped in a dielectric tester to test the data of three positions and then obtain a mean value.

[0074] The present invention has been described by referring to the aforementioned embodiments, and based thereon various variations can be made by researchers skilled in the art The scope of the present invention includes various variations falling into the scope and spirit of the appended claims.

[0075] Table 2 shows the testing results of the copper covered laminate.

TABLE-US-00002 TABLE 2 resin formulation and physical properties thereof Embod- Embod- Embod- Embod- Embod- Embod- Embod- Embod- Comparative Comparative iment iment iment iment iment iment iment iment Embodiment Embodiment 1 2 3 4 5 6 7 8 1 2 Resin BNE 35 35 35 20 20. 20 30 30 25 20 Resin PNE 10 10 10 10 10 10 0 0 5 10 Resin CNE 55 55 55 70 70 70 70 70 70 70 Phosphorus- 48 Containing Polyester Composite B-1 Phosphorus- 46 Containing Polyester Composite B-2 Phosphorus- 42 Containing Polyester Composite B-3 Phosphorus- 50 Containing Polyester Composite B-4 Phosphorus- 40 Containing Polyester Composite B-5 Phosphorus- 42 Containing Polyester Composite B-6 Phosphorus- 40 Containing Polyester Composite B-7 Phosphorus- 40 Containing Polyester Composite B-8 Phosphorus- 40 Containing Polyester Composite C-1 Phosphorus- 40 Containing Polyester Composite C-1 Flame 20 20 20 20 20 20 20 20 Retardant (aluminium hydroxide) Phosphate 30 30 Flame Retardant PX-200 Filling 10 10 10 10 10 10 10 10 10 10 Material silica) Accelerator 0.4 0.4 0.4 0.4 0.4 2MI (PHR) Accelerator 0.4 0.4 0.4 0.5 0.5 2PI (PHR) Phosphorus 1.20 1.30 1.30 1.16 1.16 1.20 1.35 1.24 1.30 1.30 Content (%) Gelling 350 345 335 350 344 332 330 375 363 370 Time (sec) Glass- 172 170 174 180 170 178 176 174 160 150 Transition Temperature (° C.) Flame 94V-0 94V-0 94V-0 94V-0 94V-0 94V-0 94V-0 94V-0 94V-1 94V-1 Retardancy Coefficient 40/238 48/243 42/235 36/213 31/201 38/218 40/232 43/235 41/232 35/220 of Thermal Expansion (α1/α2) Water 0.22 0.25 0.26 0.23 0.26 0.28 0.25 0.37 0.38 0.35 Absorption of PCT 2HR (%): Dielectric 3.9 3.9 3.7 3.9 3.9 3.9 3.7 3.7 3.8 3.8 Constant (1 GHz) Dielectric 0.005 0.005 0.005 0.005 0.005 0.005 0.004 0.004 0.004 0.004 loss factor (1 GHz)

[0076] It can be seen from the aforementioned table that in embodiments 1-8, the phosphorus-containing polyester composite of the instant disclosure can achieve a flame retardancy at UL94V-0. As compared, in the comparative embodiments 1-2, although additional flame retardants are added, only a flame retardancy as the UL94V-1 can be achieved. In terms of Tg, the phosphorus-containing polyester composite of the present invention can achieve a Tg over 170° C., while the comparative embodiments 1-2 can only achieve a Tg up to 160° C. At 1 GHz, a dielectric constant below 3.9 can be achieved in all of the embodiments, and at 1 GHz, a dielectric loss factor below 0.005 can be achieved in all of the embodiments. The heat resistance and flame retardancy of all of the embodiments comply with the IPC specifications. Therefore the composite of the present invention is applicable to the field of manufacture of high-ranking copper covered laminate material.

[0077] Although the invention has been disclosed with reference to the above embodiments, these embodiments are not intended to limit the invention. It will be apparent to those of skills in the art that various modifications and variations can be made without departing from the spirit and scope of the invention. Therefore, the scope of the invention shall be defined by the appended claims.