TWI909242B - Thermosetting resin and heat-resistant resin composition comprising the same - Google Patents

Abstract

A thermosetting resin and heat-resistant resin composition comprising the same is provided. The thermosetting resin composition includes bismaleimide resin, allyl-modified long-chain polymer resin and resin having a structure of formula A. The resin having a structure of formula A reacts with the allyl-modified long-chain polymer resin to form a network structure. The weight ratio of bismaleimide to the allyl-modified long-chain polymer resin is 0.75:1.25~1.25:0.75.

Description

Thermosetting resins and heat-resistant resin compositions comprising them

This invention relates to a resin composition, and more particularly to a thermosetting resin and a heat-resistant resin composition comprising the same.

Materials used in electronics, aerospace, and other fields typically require excellent electrical and mechanical properties as well as high heat resistance. Maleic anhydride polymers possess excellent electrical properties, high heat resistance, and high dimensional stability, but they are relatively hard and brittle after crosslinking and curing, resulting in poor mechanical properties. Adding rubber or toughening agents may affect the physical or dielectric properties of the polymer.

Therefore, how to improve the resin composition formula to take into account both high heat resistance and excellent mechanical and electrical properties, so as to further form composite materials and overcome the above-mentioned defects, has become one of the important issues that this business aims to solve.

The technical problem to be solved by this invention is to provide a thermosetting resin that addresses the shortcomings of existing technologies, comprising: bismaleimide resin, allyl long-chain polymer resin, and resin having the structure of formula A: (Formula A) A resin having the structure of Formula A reacts with the allyl long-chain polymer resin to form a network structure. The weight ratio of bismaleimide to the allyl long-chain polymer resin is 0.75:1.25 to 1.25:0.75.

In one embodiment of the present invention, the weight ratio of the bismaleimide to the allyl long-chain polymer resin is 0.9:1.1 to 1.1:0.9.

In one embodiment of the present invention, the bismaleimide is m-phenylene bismaleimide, 4,4'-bismaleimide diphenylmethane, bis(3-ethyl-5-methyl-4-maleiminobenzene)methane, or benzylmaleimide.

In one embodiment of the present invention, the weight ratio of the allyl long-chain polymer resin, the bismaleimide, and the resin having the structure of formula A is 100:85:15.

In one embodiment of the present invention, the allyl long-chain polymer resin is an allyl polybenzoxazine or an allyl-modified phenolic long-chain polymer.

To solve the above-mentioned technical problems, another technical solution adopted by the present invention is to provide a heat-resistant resin composition comprising: 15 to 25 parts by weight of epoxy resin, 10 to 20 parts by weight of benzoxazine resin and 50 to 60 parts by weight of thermosetting resin as described in claim 1.

In one embodiment of the invention, the heat-resistant resin composition further includes 2 to 6 parts by weight of a toughening agent, 2 to 6 parts by weight of a flame retardant, and 50 to 60 parts by weight of a filler.

In one embodiment of the invention, the heat-resistant resin composition further includes a solvent.

In one embodiment of the present invention, the solvent is toluene, γ-butyrolactone, methyl ethyl ketone, cyclohexanone, butanone, acetone, xylene, methyl isobutyl ketone, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, or a mixture thereof.

One of the beneficial effects of this invention is that the thermosetting resin and the heat-resistant resin composition containing it provided by this invention can form a network structure by means of "a resin having the structure of formula A reacting with the allyl long-chain polymer resin to form a network structure" and "the weight ratio of the bismaleimide to the allyl long-chain polymer resin being 0.75:1.25~1.25:0.75". This facilitates the formation of prepreg sheets with excellent electrical properties, excellent heat resistance, and low coefficient of expansion, making them suitable for applications such as HDI PCB (High-Density Interconnect PCB) and substrate-like boards.

To further understand the features and technical content of this invention, please refer to the following detailed description of this invention. However, the detailed description provided is for reference and explanation only and is not intended to limit this invention.

The following specific embodiments illustrate the implementation methods of the "thermosetting resin and heat-resistant resin composition comprising the thereof" disclosed in this invention. Those skilled in the art can understand the advantages and effects of this invention from the content disclosed in this specification. This invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of this invention. The following embodiments will further explain the relevant technical content of this invention in detail, but the disclosed content is not intended to limit the scope of protection of this invention.

It should be understood that the term "or" as used in this article may include, depending on the circumstances, any combination of one or more of the related listed items.

This invention provides a thermosetting resin comprising: a bismaleimide resin, an allyl long-chain polymer resin, and a resin having the structure of formula A. The bismaleimide resin may be m-phenylene-bismaleimide, 4,4'-bismaleimidodiphenyl methane, 3-ethyl-5-methyl-4-maleimidophenyl, or phenylmethane maleimide.

Specifically, resins with the A-structure can react with allyl long-chain polymers to form a network structure, providing high heat resistance and excellent electromechanical properties.

Furthermore, in one embodiment of the present invention, the resin having the structure of Formula A is synthesized by placing 17.9 g of 4-amino-2-fluorobenzotrifluoride (produced by Merck) and 150 g of dimethylacetamide (DMAC) in a 1-liter four-necked separable reaction flask equipped with a heating device, thermometer, stirrer, and cooling pipe. The mixture is heated to approximately 60°C and stirred until completely dissolved. Subsequently, while maintaining stirring, 10 g of maleic anhydride is gradually added over 20 minutes, and the temperature of the synthesis solution is raised to 90°C. Then, 1 g of 5-ethyl-2-methylpyridine is added. The mixture was gradually heated to 140°C and reacted for 1 hour. The reaction formula is shown in reaction formula A below, which yields resin BMI-F with the structure of formula A. Reaction A

Following the above, after reacting at 140°C for 1 hour, the temperature was lowered to room temperature, and 400 grams of methanol were added to precipitate the resin. After washing with methanol three times and drying, a resin with the structure of formula A was obtained.

On the other hand, the allyl long-chain polymer resin of the present invention can be acrylonitrile benzoxazine resin or acrylonitrile phenolic resin. Specifically, the allyl long-chain polymer resin of the present invention can be synthesized by the method described in the following synthesis examples 1 to 5.

[Synthetic Example 1] Preparation of propenylbenzoxazine (BZ-A) resin

100 grams of BPA-type benzoxazine resin (Yuan Hong BPA-BZ) and 300 grams of toluene were added to a 1-liter four-necked separable reaction flask equipped with a heating device, thermometer, stirrer, coolant, dropper, and pressure recovery device to form a synthesis solution. 15 grams of potassium hydroxide (KOH) were added, and the synthesis solution was heated to approximately 40°C and stirred uniformly. While maintaining stirring, 38 grams of allyl chloride were gradually added to the synthesis solution over 20 minutes, and the reaction was carried out for 1 hour. During this time, the temperature of the synthesis solution was gradually increased to approximately 90°C, and the solution was heated and maintained at approximately 90°C for 1 hour. The allyl chloride was then removed at 90°C under reduced pressure (90 mmHg). Heating and stirring were then stopped, 300 g of pure water was added, and the mixture was allowed to stand for approximately 20 minutes until the synthetic solution separated into two layers. The lower aqueous phase was removed, and the mixture was washed three times with water until the wash solution was neutral, yielding 410 g of a propenyl-grafted benzoxazine (BZ-A) toluene solution. The reaction formula is shown in Reaction Formula 1 below. Reaction 1

[Synthesis Example 2] Preparation of Acrylic Phenolic Resin (PN-A)

100 g of phenolic resin (Changchun-produced Phenolic Novolac) and 300 g of toluene were added to a reaction vessel, along with 15 g of potassium hydroxide (KOH). While stirring, 38 g of allyl chloride was gradually added to the synthesis solution over 20 minutes, and the reaction was carried out for 1 hour. The allyl chloride was then removed at 90°C under reduced pressure (90 mmHg). Heating and stirring were then stopped, 300 g of pure water was added, and the mixture was allowed to stand for approximately 20 minutes until the synthesis solution separated into two layers. The lower aqueous phase was removed, and the mixture was washed three times with water until the wash solution was neutral, yielding a 417 g toluene solution of propylene-grafted phenolic (PN-A) resin. The reaction formula is shown in Reaction Formula 2 below. Reaction 2

[Synthesis Example 3] Preparation of Acrylic Phenolic Resin (Nath-A)

100 g of naphthol aralkylphenol resin (SN-495 Nathpthlene phenolic Novolac, manufactured by Nippon Steel, Japan) and 300 g of toluene were added to a reaction vessel, along with 15 g of potassium hydroxide (KOH). While stirring, 38 g of allyl chloride was gradually added to the synthesis solution over 20 minutes, and the reaction was carried out for 1 hour. The allyl chloride was then removed at 90°C under reduced pressure at 90 mmHg. Subsequently, heating and stirring were stopped, 300 grams of pure water were added, and the mixture was allowed to stand for about 20 minutes until the synthetic solution separated into two layers. The lower aqueous phase was then removed, and the mixture was washed three times with water until the wash solution was neutral, thus obtaining a 421 g solution of propylene-grafted phenolic (Nath-A) resin toluene. The reaction formula is shown in reaction formula 3 below. Reaction 3

[Synthesis Example 4] Preparation of Acrylic Phenolic Resin (DCDPN-A)

100 g of DCDP phenolic resin (ERM-6105, manufactured by SONGWON, Korea) and 300 g of toluene were added to a reaction vessel, along with 15 g of potassium hydroxide (KOH). While stirring, 38 g of allyl chloride was gradually added to the synthesis solution over 20 minutes, and the reaction was carried out for 1 hour. The allyl chloride was then removed at 90°C under reduced pressure (90 mmHg). Heating and stirring were then stopped, 300 g of pure water was added, and the mixture was allowed to stand for approximately 20 minutes until the synthesis solution separated into two layers. The lower aqueous phase was removed, and the mixture was washed three times with water until the wash solution was neutral, yielding a 417 g toluene solution of propylene-grafted DCDPN phenolic resin (DCDPN-A). The reaction equation is shown in reaction equation 4 below. Reaction 4

[Synthesis Example 5] Preparation of Bisphenol Type Acrylic Phenolic Resin (BPN-A)

100 g of phenolic resin (4,40-diglycidyl biphenyl novolac resin (GPH-65) produced by DIC Japan) and 300 g of toluene were added to a reaction vessel, along with 15 g of potassium hydroxide (KOH). While maintaining stirring, 38 g of allyl chloride was gradually added to the synthesis solution over 20 minutes, and the reaction was carried out for 1 hour. The allyl chloride was then removed at 90°C under reduced pressure at 90 mmHg. Subsequently, heating and stirring were stopped, 300 grams of pure water were added, and the mixture was allowed to stand for about 20 minutes until the synthetic solution separated into two layers. The lower aqueous phase was then removed, and the mixture was washed three times with water until the wash solution was neutral, thus obtaining a 417 g solution of propylene-grafted Biphenyl phenolic resin (BPN-A) toluene. The reaction formula is shown in Reaction Formula 5 below. Reaction 5

Furthermore, the method for preparing the thermosetting resin of the present invention is described in Examples 1 to 9 below. The reaction formulas of Examples 1 to 9 are generally as shown in the following reaction formula 6. Reaction 6

[Implementation Example 1]

100g of the benzoxazine resin (BZ-A) of Synthesis Example 1 and 200g of methyl ethyl ketone (MEK) were added to a 1-liter four-necked separable reaction flask equipped with a heating device, thermometer, stirrer and cooling pipe device to form a synthesis solution. The synthesis solution was heated to about 70°C and stirred evenly to dissolve it. While maintaining stirring, 85 grams of 4,4'-bismaleimidodiphenyl methane resin and 15 grams of resin BMI-F with structure A were gradually added to the synthesis solution over 20 minutes. The temperature of the synthesis solution rose to approximately 110°C. The solution was heated and maintained at approximately 110°C for 1 hour. The reaction was then stopped, yielding a clear, brown solution. The product obtained was named BMBZ-1. When tested with a gelling machine at 200°C, the gelation time of BMBZ-1 was 346 seconds.

[Implementation Example 2]

100g of the benzoxazine resin (BZ-A) of Synthesis Example 1 and 200g of butanone were added to a 1-liter four-necked separable reaction flask equipped with a heating device, thermometer, stirrer and cooling pipe device to form a synthesis solution. The synthesis solution was heated to about 70°C and stirred evenly to dissolve it. While maintaining stirring, 85 grams of bis(3-ethyl-5-methyl-4-maleimidophenyl)methane resin and 15 grams of resin BMI-F with formula A were gradually added to the synthesis solution over 20 minutes. The temperature of the synthesis solution rose to approximately 110°C. The solution was heated and maintained at approximately 110°C for 1 hour. The reaction was then stopped, yielding a clear, brown solution. The product obtained was named BMBZ-2. When tested with a gelling machine at 200°C, the gelation time of BMBZ-2 was 365 seconds.

[Implementation Example 3]

100 g of the benzoxazine resin (BZ-A) from Synthesis Example 1 and 200 g of butanone were added to a 1-liter four-necked separable reaction flask equipped with a heating device, thermometer, stirrer, and cooling pipe to form a synthesis solution. The synthesis solution was heated to approximately 70°C and stirred uniformly to dissolve it. While maintaining stirring, 85 g of benzylmaleimide (BMI-2300) and 15 g of resin BMI-F having the structure of formula A were gradually added to the synthesis solution over 20 minutes. At this time, the temperature of the synthesis solution rose to approximately 110°C. The synthesis solution was heated and maintained at approximately 110°C and reacted for 1 hour. The reaction is then stopped, yielding a clear, brown solution. The product obtained is called BMBZ-3. When tested with a gelling machine at 200°C, the gelation time of BMBZ-3 is 355 seconds.

[Implementation Example 4]

100 g of the propylene phenolic resin (PN-A) from Synthesis Example 2 and 200 g of butanone were added to a 1-liter four-necked separable reaction flask equipped with a heating device, thermometer, stirrer, and cooling pipe to form a synthesis solution. The synthesis solution was heated to approximately 70°C and stirred uniformly to dissolve it. While maintaining stirring, 85 g of 4,4'-bismaleimine diphenylmethane and 15 g of resin BMI-F having the structure of formula A were gradually added to the synthesis solution over 20 minutes. At this point, the temperature of the synthesis solution rose to approximately 110°C. The synthesis solution was heated and maintained at approximately 110°C and reacted for 1 hour. The reaction is then stopped, yielding a clear, brown solution. The product obtained is called BMPN-1. When tested with a gelling machine at 200°C, the gelation time of BMPN-1 is 346 seconds.

[Implementation Example 5]

100g of the propylene phenolic resin (PN-A) from Synthesis Example 2 and 200g of butanone were added to a 1-liter four-necked separable reaction flask equipped with a heating device, thermometer, stirrer, and cooling pipe to form a synthesis solution. The synthesis solution was heated to approximately 70°C and stirred uniformly to dissolve it. While maintaining stirring, 85g of bis(3-ethyl-5-methyl-4-maleiminobenzene)methane resin and 15g of resin BMI-F having the structure of formula A were gradually added to the synthesis solution over 20 minutes. At this point, the temperature of the synthesis solution rose to approximately 110°C. The synthesis solution was heated and maintained at approximately 110°C and reacted for 1 hour. The reaction is then stopped, yielding a clear, brown solution. The product obtained is called BMPN-2. When tested with a gelling machine at 200°C, the gelation time of BMPN-2 is 346 seconds.

[Implementation Example 6]

100g of the propylene phenolic resin (PN-A) from Synthesis Example 2 and 200g of butanone were added to a 1-liter four-necked separable reaction flask equipped with a heating device, thermometer, stirrer, and cooling pipe to form a synthesis solution. The synthesis solution was heated to approximately 70°C and stirred uniformly to dissolve it. While maintaining stirring, 85g of benzyl maleimide (BMI-2300) and 15g of resin BMI-F having the structure of formula A were gradually added to the synthesis solution over 20 minutes. At this point, the temperature of the synthesis solution rose to approximately 110°C. The synthesis solution was heated and maintained at approximately 110°C and reacted for 1 hour. The reaction is then stopped, yielding a clear, brown solution. The product obtained is called BMPN-3. When tested with a gelling machine at 200°C, the gelation time of BMPN-3 is 346 seconds.

[Implementation Example 7]

100 g of the propylene phenolic resin (Nath-A) from Synthesis Example 3 and 200 g of butanone were added to a 1-liter four-necked separable reaction flask equipped with a heating device, thermometer, stirrer, and cooling pipe to form a synthesis solution. The synthesis solution was heated to approximately 70°C and stirred uniformly to dissolve it. While maintaining stirring, 85 g of bis(3-ethyl-5-methyl-4-maleiminobenzene)methane resin and 15 g of resin BMI-F having the structure of formula A were gradually added to the synthesis solution over 20 minutes. At this point, the temperature of the synthesis solution rose to approximately 110°C. The synthesis solution was heated and maintained at approximately 110°C and reacted for 1 hour. The reaction is then stopped, yielding a clear, brown solution. The product obtained is called BMNa. When tested with a gelling machine at 200°C, the gelation time of BMNa is 346 seconds.

[Implementation Example 8]

100 g of the acrylic phenolic resin (DCDPN-A) from Synthesis Example 4 and 200 g of butanone were added to a 1-liter four-necked separable reaction flask equipped with a heating device, thermometer, stirrer, and cooling pipe to form a synthesis solution. The synthesis solution was heated to approximately 70°C and stirred uniformly to dissolve it. While maintaining stirring, 85 g of bis(3-ethyl-5-methyl-4-maleiminobenzene)methane resin and 15 g of resin BMI-F having the structure of formula A were gradually added to the synthesis solution over 20 minutes. At this point, the temperature of the synthesis solution rose to approximately 110°C. The synthesis solution was heated and maintained at approximately 110°C and reacted for 1 hour. The reaction is then stopped, yielding a clear, brown solution. The product obtained is called BMDC. When tested with a gelling machine at 200°C, the gelation time of BMDC is 346 seconds.

[Implementation Example 9]

100 g of the bisphenol-type acrylic resin (BPN-A) from Synthesis Example 5 and 200 g of butanone were added to a 1-liter four-necked separable reaction flask equipped with a heating device, thermometer, stirrer, and cooling pipe to form a synthesis solution. The synthesis solution was heated to approximately 70°C and stirred uniformly to dissolve it. While maintaining stirring, 85 g of bis(3-ethyl-5-methyl-4-maleiminobenzene)methane resin and 15 g of resin BMI-F having the structure of formula A were gradually added to the synthesis solution over 20 minutes. At this point, the temperature of the synthesis solution rose to approximately 110°C. The synthesis solution was heated and maintained at approximately 110°C and reacted for 1 hour. The reaction is then stopped, yielding a clear, brown solution. The product obtained is called BMBPN. When tested with a gelling machine at 200°C, the gelation time of BMBPN is 346 seconds.

The composition and gelation time of Examples 1 to 9 are shown in Table 1. In Table 1, BMI-1 is 4,4'-bismaleimidodiphenyl methane resin; BMI-2 is bis(3-ethyl-5-methyl-4-maleimidophenyl)methane; and BMI-3 is phenylmethane maleimide (BMI-2300) resin. BMI-1, BMI-2, and BMI-3 are all produced by ACR.

Table 1 Implementation Examples 1 2 3 4 5 6 7 8 9 code BMBZ-1 BMBZ-2 BMBZ-3 BMPN-1 BMPN-2 BMPN-3 BMNa BMDC BMBPN BZ-A 100 100 100 PN-A 100 100 100 Nath-A 100 DCDP-A 100 BPN-A 100 BMI-F 15 15 15 15 15 15 15 15 15 BMI-1 85 85 BMI-2 85 85 85 85 85 BMI-3 85 85 Gel time (seconds) 346 365 355 346 346 346 346 346 346

The heat-resistant resin composition of this invention can be prepared into a varnish-like form for subsequent processing by uniformly mixing and dissolving or dispersing the various components of the resin composition, including BMI-modified benzoxazine, fillers, and toughening agents, in a solvent using a homogenizer. The solvent can be any inert solvent that can dissolve or disperse the various components of the resin composition but does not react with those components. Solvents that can be used to dissolve or disperse the components of a resin composition include, but are not limited to: toluene, γ-butyrolactone, methyl ethyl ketone, cyclohexanone, butanone, acetone, xylene, methyl isobutyl ketone, N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), and N-methylpyrolidone (NMP). Each solvent can be used alone or in combination. There are no particular limitations on the amount of solvent used; in principle, it is sufficient to ensure that the components of the resin composition are uniformly dissolved or dispersed therein. In a preferred embodiment of the present invention, a mixture of toluene, methyl ethyl ketone, and γ-butyrolactone is used as the solvent.

Furthermore, Table 2 shows the composition and characteristics of embodiments E1 to E10 and comparative examples C1 to C3 of the heat-resistant resin composition of the present invention.

Table 2 (Unit: parts by weight) Implementation examples/comparative examples E1 E2 E3 E4 E5 E6 E7 E8 E9 E10 C1 C2 C3 Epoxy resin Long chain type 5 5 5 5 5 5 5 5 5 5 5 5 5 CNE 15 15 15 15 15 15 15 15 15 15 15 15 15 BZ Allyl-BZ 5 5 5 5 5 5 5 5 5 2.5 5 5 5 thermosetting resins ODA-BZ 10 10 10 10 10 10 10 10 10 7.5 10 10 10 BMBZ-1 55 BMBZ-2 55 BMBZ-3 55 BMPN-1 55 BMPN-2 55 BMPN-3 55 BMNa 55 BMDC 55 BMBPN 55 60 BMI-1 55 BMI-2 55 BMI-3 55 Resilience enhancer SEBS 5 5 5 5 5 5 5 5 5 5 5 5 5 Flame retardant SPB-100 5 5 5 5 5 5 5 5 5 5 5 5 5 filler SiO ₂ 55 55 55 55 55 55 55 55 55 55 55 55 55 substrate Cu Foil 1/3oz Cu Cu Cu Cu Cu Cu Cu Cu Cu Cu Cu Cu Cu Measuring physical properties Tg ( ^o C) 191 192 183 187 189 188 192 183 187 184 187 193 192 XY-CTE (ppm) 43 44 45 42 46 42 48 41 47 38 42 32 39 Next, intensity (lbf/in) 3.3 3.4 3.5 3.4 3.3 3.2 3.4 3.6 3.2 3.2 2.6 2.8 2.7 Heat resistance 288 ^° C Solder ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Water absorption (%) 0.45 0.47 0.43 0.42 0.41 0.38 0.39 0.38 0.42 0.45 0.62 0.66 0.75 Dk(10GHz) 3.92 3.98 3.94 3.96 3.94 3.98 3.97 3.96 3.93 3.96 4.17 4.19 4.18 Df(10GHz) 0.0083 0.0082 0.0085 0.0084 0.0083 0.0085 0.0086 0.0085 0.0082 0.0084 0.0105 0.0105 0.0115 Flexural endurance test (times) 30 34 33 27 32 29 32 33 32 28 12 16 13 Among them, ODA-BZ and Allyl-BZ are benzoxazine resins produced by Yuan Hong; the filler is 10um cut SiO2 produced by Sibico; the CNE epoxy resin is Chang Chun synthetic resin, and the long-chain epoxy resin is Huntsman PKFE; the toughening agent is styrene copolymer (SEBS) produced by Lee Chang Jung Co., Ltd.; SPB-100 is a phosphorus-based flame retardant; and the copper foil is H1 1/3 oz produced by Nan Ya Co., Ltd.

Next, strength refers to the adhesion of the metal foil to the laminated prepreg sheet. The strength test is performed by tearing a 1/8-inch wide copper foil vertically from the board surface, and the strength required to express the strength of the adhesion.

The heat resistance test involves immersing the dried metal foil laminate in a solder bath at 288°C for 100 seconds, repeating the process three times. If the appearance remains unchanged, it indicates excellent heat resistance and is recorded as "○"; if there are bubbles or protrusions on the appearance, it indicates poor heat resistance and is recorded as "×".

The glass transition temperature (Tg) was measured using a Thermal Mechanical Analyzer (TMA) according to the method specified in IPC-TM-650 2.4.24.4.

The water absorption test is conducted according to IPC-TM-650 2.6.2. The copper foil of the test specimen is completely etched away, and its size is 10cm*10cm. First, the specimen is baked at 105℃ for half an hour, then placed in a drying oven to cool and weighed. Then, the specimen is immersed in pure water at 23℃ for 24 hours. After that, it is removed, wiped dry, and left to stand before being weighed. The degree of water absorption of the specimen can be calculated by subtracting the weight of the specimen before and after the treatment.

The dielectric constant (Dk) is measured according to the IPC-TM-650 2.5.5 testing specification. The dielectric constant represents the electronic insulation characteristics of the manufactured film; the lower the value, the better the electronic insulation characteristics. The dielectric loss (Df) is measured according to the IPC-TM-650 2.5.5 testing specification.

The X/Y axis coefficient of thermal expansion (CTE) was measured according to the IPC-TM-650-2.4.24 testing specification. A thermomechanical analyzer (TMA) was used to measure the coefficient of thermal expansion (CTE) of the sample at temperatures below Tg. The flexural endurance - MIT test (flexural endurance test) was measured according to JIS P8115, where R = 1.0 mm, 90-degree bending frequency 175 times/minute, and load 250g, to measure the number of bends the sample could withstand.

[Beneficial effects of the implementation]

One of the beneficial effects of this invention is that the thermosetting resin provided by this invention, namely the heat-resistant resin composition containing it, can form a network structure by "a resin having the structure of formula A reacting with the allyl long-chain polymer resin" and "the weight ratio of the bismaleimide to the allyl long-chain polymer resin is 0.75:1.25~1.25:0.75", which is conducive to forming a prepreg with excellent electrical properties, excellent heat resistance and low coefficient of expansion, and is suitable for applications such as HDI PCB (high-density interconnect PCB) and substrate-like boards.

In the resin composition of the present invention, the weight ratio of bismaleimide to the allyl long-chain polymer resin is 0.75:1.25~1.25:0.75, preferably 0.9:1.1~1.1:0.9, to facilitate the formation of prepreg sheets with excellent electrical properties, excellent heat resistance, and low coefficient of expansion.

Furthermore, the use of resins with the Formula A structure is beneficial to CTE and heat resistance. Moreover, this invention utilizes the low dielectric and low moisture absorption properties of resins with the Formula A structure to crosslink and cure them with allyl long-chain polymers into a resin composition with excellent thermal and electrical properties. The weight ratio of the allyl long-chain polymer, bismaleimide, and the resin with the Formula A structure is 100:85:15, which improves the efficiency of the allyl long-chain polymer reaction to form a network structure. Therefore, the thermosetting resin of this invention, when used to impregnate a substrate, can give the substrate better flexural strength.

On the other hand, the heat-resistant resin composition of the present invention comprises 15 to 25 parts by weight of epoxy resin, 10 to 20 parts by weight of benzoxazine resin, and 50 to 60 parts by weight of the thermosetting resin of Examples 1 to 9. When the content of epoxy resin is less than 15 parts by weight, the toughness of the heat-resistant resin composition is poor; when the content of epoxy resin is greater than 25 parts by weight, the impact resistance of the cured heat-resistant resin composition deteriorates. When the content of benzoxazine resin is less than 10 parts by weight, the moisture absorption rate of the heat-resistant resin composition deteriorates; when the content of benzoxazine resin is greater than 20 parts by weight, the cured heat-resistant resin composition becomes too brittle, resulting in poor processability. When the content of thermosetting resin is less than 50 parts by weight, the heat resistance of the heat-resistant resin composition is poor. When the content of thermosetting resin is greater than 60 parts by weight, it will affect the processing performance of the heat-resistant resin composition.

Preferably, the heat-resistant resin composition of the present invention comprises 18 to 22 parts by weight of epoxy resin, 13 to 16 parts by weight of benzoxazine resin, and 53 to 56 parts by weight of thermosetting resin of Examples 1 to 9. In a preferred embodiment of the present invention, the epoxy resin is composed of long-chain epoxy resin and CNE epoxy resin in a weight ratio of 1:3, and the benzoxazine resin is composed of Allyl-BZ and ODA-BZ in a weight ratio of 1:2. This results in a heat-resistant resin composition with good high-temperature insulation, strong arc resistance and tracking resistance. After curing, this heat-resistant resin composition can produce a material with high crosslinking density and improved flexibility, making it more suitable for applications in electronics, aerospace and other fields.

The above-disclosed content is merely a preferred feasible embodiment of the present invention and is not intended to limit the scope of the patent application of the present invention. Therefore, all equivalent technical changes made using the contents of the present invention's description and drawings are included within the scope of the patent application of the present invention.

Claims (7)

A thermosetting resin comprising: a bismaleimide resin, wherein the bismaleimide is m-phenylene bismaleimide, 4,4'-bismaleimide diphenylmethane, bis(3-ethyl-5-methyl-4-maleiminophenyl)methane, or benzylmaleimide; an allyl long-chain polymer resin, wherein the allyl long-chain polymer resin is allyl polybenzoxazine or an allyl-modified phenolic long-chain polymer; and a resin having the structure of formula A: Formula A; wherein the resin having the structure of Formula A reacts with the allyl long-chain polymer resin to form a network structure, and the resin having the structure of Formula A is synthesized from 4-amino-2-fluorotrifluorobenzo, dimethylacetamide, maleic anhydride and 5-ethyl-2-methylpyridine; wherein the weight ratio of the bismaleimide to the allyl long-chain polymer resin is 0.75:1.25~1.25:0.75. The thermosetting resin as described in claim 1, wherein the weight ratio of the bismaleimide to the allyl long-chain polymer resin is 0.9:1.1 to 1.1:0.9. The thermosetting resin as claimed in claim 1, wherein the weight ratio of the allyl long-chain polymer resin, the bismaleimide and the resin having the structure of formula A is 100:85:15. A heat-resistant resin composition comprising: 15 to 25 parts by weight of an epoxy resin; 10 to 20 parts by weight of a benzoxazine resin; and 50 to 60 parts by weight of a thermosetting resin as described in claim 1. The heat-resistant resin composition as described in claim 4 further comprises 2 to 6 parts by weight of a toughening agent, 2 to 6 parts by weight of a flame retardant, and 50 to 60 parts by weight of a filler. The heat-resistant resin composition as described in claim 4 further includes a solvent. The heat-resistant resin composition as described in claim 6, wherein the solvent is toluene, γ-butyrolactone, methyl ethyl ketone, cyclohexanone, butanone, acetone, xylene, methyl isobutyl ketone, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, or a mixture thereof.