TWI381009B - Phosphorus-containing bexzoxazine resin with various substituents and method for preparing the same - Google Patents

Description

Phosphorus-containing bifunctional Benzoxazine resin having different substituents and method for producing same

The present invention relates to a method for producing a phosphorus-containing bifunctional Benzoxazine resin, and more particularly to a method for synthesizing high purity, high yield Benzoxazine from a phosphorus-containing bisamine.

Phenolic resin is a commonly used thermosetting resin obtained by polycondensation of a phenolic monomer and an aldehyde monomer. Benzoxazine, which has been developed in recent years, is also a kind of phenolic resin, which is characterized by ring-opening hardening after heating. Compared with traditional phenolic resin, Benzoxazine has high glass transition temperature (Tg), high modulus (Modulus), low moisture absorption, good electrical properties, high coke residue (Char Yield), no need to strengthen acid during hardening. The catalyst, the by-product during hardening, and the small volume change rate during hardening.

However, the composition of the phenolic resin is carbon, hydrogen, oxygen, and it is easy to burn, which is a major disadvantage in its application. With the development of the electronics industry, product requirements are becoming thinner and lighter, so the traditional Pin Through Hole (PTH) has been developed into Surface Mount Technology (SMT): such as the ball-foot array matrix (Ball). Grid Array (BGA), Flip Chip Package, and Chip Size Package (CSP) package methods have driven the rapid development of printed circuit boards in the direction of "high density" and "multilayer". In addition, the semiconductor industry is increasingly demanding the high temperature and flame resistance requirements of materials. For electronic materials, the specification must reach UL-94 V-0, so the incomprehensibility of electronic materials is also an inevitable trend.

The flame-retardant Benzoxazine products currently available on the market must be blended with carbon fiber in their resins to increase their flame resistance. However, the mere use of its Benzoxazine resin is not a flame retardant effect, so how to make the Benzoxazine resin have flame retardant properties is a concern of many electronics industries. In order to make polymer materials have incombustible properties, many domestic and foreign scholars have also conducted related research. Therefore, some scholars have suggested that the introduction of alkyne, deoxybenzin or phosphorus-containing materials can improve the flame retardant properties of molecular materials.

It can be observed from many literatures that most of the bifunctional Benzoxazines are prepared from aromatic bisphenols and monofunctional amine monomers and formaldehyde, so we can introduce aromatics with flame retardant properties into aromatics. Among the bisphenols or monofunctional amines, for example, a bisphenol monomer having a phosphorus-oxygen bond or a derivative of DOPO is introduced to achieve the purpose of imparting flame retardant properties to Benzoxazine.

The literature on aromatic diamine-based bifunctional Benzoxazine monomers is quite rare. The main reason is that if the aromatic diamine is synthesized by the traditional route, it will produce a gel phenomenon. The main reason is that when the bisamine reacts with formaldehyde and phenol, the diamine will react with formaldehyde. An insoluble triazine intermediate product, therefore, the Benzoxazine monomer based on bisamine cannot be synthesized smoothly.

Therefore, in order to solve this problem, in the present invention, a novel synthetic route to synthesize a Benzoxazine monomer based on a bisamine is proposed by the concept of molecular design. And because of the electronics industry's need for flame retardancy, we have introduced phosphorus-containing groups in the structure of bisamines, using a series of phosphorus-containing diamines with various substituents as a matrix to synthesize flame retardant properties. Benzoxazine resin.

One aspect of the present invention is to provide a phosphorus-containing bifunctional Benzoxazine resin having a structure of the formula (I):

Wherein R1 to R3 are each selected from the group consisting of a hydrogen atom, a C1 to C6 alkyl group, a C3 to C6 cycloalkyl group, and a phenyl group. According to a specific embodiment, when R1 of the compound of the above formula (I) is a methyl group and R2 to R3 are a methyl group, the structural formula of the compound of the formula (I) may be:

According to another embodiment, when R1 of the compound of formula (I) is methyl and R2 to R3 are methyl, the structural formula of the compound of formula (I) may be:

According to a specific embodiment, when R1 of the compound of the above formula (I) is a methyl group and R2 to R3 are an ethyl group, the structural formula of the compound of the formula (I) may be:

According to a specific embodiment, when R1 of the compound of the above formula (I) is a phenyl group and R2 to R3 are a hydrogen atom, the structural formula of the compound of the formula (I) may be:

Another aspect of the present invention is to provide a phosphorus-containing bifunctional Benzoxazine resin having a diether having a structure of the formula (V):

Wherein R4 is one selected from the group consisting of C1 to C6 alkyl, C3 to C6 cycloalkyl and phenyl.

According to a specific embodiment, when R4 of the compound of the above formula (V) is a methyl group, the structural formula of the compound of the formula (V) may be:

Another aspect of the invention is to provide a method of preparing a phosphorus-containing bifunctional Benzoxazine.

According to a specific embodiment, the method of the present invention for preparing a phosphorus-containing bifunctional Benzoxazine can utilize a phosphorus-containing bisamine as a matrix to synthesize a phosphorus-containing Benzoxazine. The structure of the phosphorus-containing diamine is as follows:

Benzoxazine having a different structure was prepared by a series of reactions using a phosphorus-containing bisamine (IV) and 2-hydroxybenzaldehyde. In this embodiment, the method of making the Benzoxazine resin can be divided into the following three stages.

In the first stage of the reaction, the phosphorus-containing bisamine (IV) and 2-hydroxybenzaldehyde are first dissolved in a mixed solvent, and a Dean-Stark apparatus is set up to carry out the water removal reaction at boiling temperature. The reaction is carried out to firstly form a reaction intermediate (III) having an imine bond, followed by removing the hydrophobic solvent in the mixed solvent, waiting for the reaction system to fall to room temperature, and directly performing the second-stage reaction.

The mixed solvent which can be used in the first stage includes a reaction solvent such as DMAC/Toluene, NMP/Toluene, DMSO/Toluene, DMF/Xylene, DMAC/Xylene, NMP/Xylene, DMSO/Xylene. The hydrophobic solvent contains Toluene and Xylene.

In the second-stage reaction, after waiting for the completion of the first-stage reaction to room temperature, NaBH4 is directly added to the above reaction system, and the reduction reaction is carried out at room temperature, and then the reaction liquid is dropped into water to precipitate. Body (II).

In the third stage reaction, the reaction intermediate (II) is dissolved in a solvent, and then an aqueous formaldehyde solution (or polyoxymethylene) is placed in the reactor, stirred at 35 ° C for a while, and then the temperature is raised to reflux temperature. Finally, the solvent was removed by a rotary concentrator to give the final product (I). The solvent which can be used in the third stage comprises a reaction solvent such as Toluene, Xylene, CHCl ₃ or Dioxane.

According to this embodiment, the above three-stage reaction is represented by the chemical formula as follows:

Wherein R1 is selected from the group consisting of C1~C6 alkyl, C3~C6 cycloalkyl and phenyl; R2~R3 are respectively selected from hydrogen atom, C1~C6 alkyl, C3~C6 ring One of a group consisting of an alkyl group and a phenyl group.

According to another embodiment of the present invention, a phosphorus-containing Benzoxazine having an ether group can be synthesized by using a phosphorus-containing diether amine as a substrate, and the structure of the phosphorus-containing diether amine is as follows:

Wherein R4 is one selected from the group consisting of C1 to C6 alkyl groups, C3 to C6 cycloalkyl groups, and phenyl groups.

Phosphorus-containing Benzoxazine was synthesized in the same manner in a three-stage manner using this phosphorus-containing dietheramine (VIII). In the first stage of the reaction, the phosphorus-containing dietheramine (VIII) and 2-hydroxybenzaldehyde are first dissolved in a mixed solvent, and a Dean-Stark apparatus is set up to carry out the water removal reaction at the boiling temperature. The reaction is carried out to form a reaction intermediate (VII) having an imine bond, and then the hydrophobic solvent in the mixed solvent is removed, and the reaction system is allowed to fall to room temperature to directly carry out the second-stage reaction.

The mixed solvent which can be used in the first stage includes a reaction solvent such as DMAC/Toluene, NMP/Toluene, DMSO/Toluene, DMF/Xylene, DMAC/Xylene, NMP/Xylene, DMSO/Xylene. The hydrophobic solvent contains Toluene and Xylene.

In the second-stage reaction, after waiting for the completion of the first-stage reaction to room temperature, NaBH4 is directly added to the above reaction system, and the reduction reaction is carried out at room temperature, and then the reaction liquid is dropped into water to precipitate. Body (VI).

In the third stage reaction, the reaction intermediate (VI) is dissolved in a solvent, and then an aqueous formaldehyde solution (or polyoxymethylene) is placed in the reactor, stirred at 35 ° C for a while, and then the temperature is raised to reflux temperature. Finally, the solvent was removed by a rotary concentrator to give the final product (V). The solvent which can be used in the third stage comprises a reaction solvent such as Toluene, Xylene, CHCl ₃ or Dioxane.

According to this embodiment, the above three-stage reaction is represented by the chemical formula as follows:

Wherein R 4 is one selected from the group consisting of C 1 -C 6 alkyl, C 3 -C 6 cycloalkyl and phenyl.

The advantages and spirit of the present invention will be further understood from the following detailed description of the invention.

In accordance with an embodiment of the present invention, a method of preparing a phosphorus-containing bifunctional Benzoxazine can be illustrated in Scheme 1, and Flowchart 1 is illustrated in the following specific examples.

Synthesis Example 1: Synthesis of Compound (I-A)

Take 21.32 g (0.05 mol) of phosphorus-containing diamine monomer (IV-A) and 12.82 g (0.105 mol) of 2-hydroxybenzaldehyde dissolved in DMAc/Toluene, stir in a three-neck reaction flask and set up Dean- The Dean-Stark unit performs a water removal reaction. The reaction was carried out at boiling temperature for 12 hours. At the end of the reaction, Toluene was removed to room temperature. NaBH4 was added to the three-necked flask in portions, and the reaction was stirred at room temperature for 24 hours. After the reaction was completed, the solution was dropped into deionized water to obtain white. The powder was precipitated, suction filtered and the cake was dried to give a white powder (II-A) 30.33 g, yield 95%.

Then, 10.0 g (0.0156 mol) of monomer (II-A) was dissolved in Toluene, and 1.4976 g (0.0499 mol) of Paraformaldehyde was placed in a three-neck reaction flask, and reacted at boiling temperature for 24 hours. The filtrate Toluene was drained using a rotary concentrator to give a pale yellow powder (IA) 10.27 g, yield 99%. Please refer to FIG. 1. FIG. 1 is a schematic diagram showing the 1H NMR of the I-A compound.

Synthesis Example 2: Synthesis of Compound (I-B)

Take 22.73 g (0.05 mol) of phosphorus-containing diamine monomer (IV-B) and 12.82 g (0.105 mol) of 2-hydroxybenzaldehyde dissolved in DMAc/Toluene, stir in a three-neck reaction flask and set up Dean- The Dean-Stark unit performs a water removal reaction. The reaction was carried out at boiling temperature for 12 hours. At the end of the reaction, Toluene was removed to room temperature. NaBH4 was added to the three-necked flask in portions, and the reaction was stirred at room temperature for 24 hours. After the reaction was completed, the solution was dropped into deionized water to obtain white. The powder was precipitated, suction filtered and the filter cake was dried to give white powder (II-B) 30.33 g, yield 91%.

Then, 10.0 g (0.0149 mol) of monomer (II-B) was dissolved in Toluene, and 1.437 g (0.0479 mol) of Paraformaldehyde was placed in a three-neck reaction flask, and reacted at boiling temperature for 24 hours. The filtrate Toluene was drained using a rotary concentrator to give a pale yellow powder (IB) of 10.09 g, yield 98%.

Synthesis Example 3: Synthesis of Compound (I-C)

Take the phosphorus diamine monomer (IV-C) 24.123 g (0.05 mol), 2-hydroxybenzaldehyde 12.82 g (0.105 mol) dissolved in DMAc/Toluene, stir in a three-neck reaction flask and set up Dean - The Dean-Stark unit performs a water removal reaction. The reaction was carried out at boiling temperature for 12 hours. At the end of the reaction, Toluene was removed to room temperature. NaBH4 was added to the three-necked flask in portions, and the reaction was stirred at room temperature for 24 hours. After the reaction was completed, the solution was dropped into deionized water to obtain white. The powder was precipitated, suction filtered and the filter cake was dried to give white powder (II-C) 32.66 g, yield 94%.

Then, 10.0 g (0.0143 mol) of monomer (II-C) was dissolved in Toluene, and 1.381 g (0.046 mole) of Paraformaldehyde was placed in three. The reaction was carried out at a boiling temperature for 24 hours in a neck reaction flask. After the reaction was completed, the filtrate Toluene was drained using a rotary concentrator to obtain a pale yellow powder (I-C) 10.14 g, yield 98%.

Synthesis Example 4: Synthesis of Compound (I-D)

Take the phosphorus diamine monomer (IV-D) 24.426 g (0.05 mol), 2-hydroxybenzaldehyde 12.82 g (0.105 mol) dissolved in DMAc/Toluene, stir in a three-neck reaction flask and set up Dean - The Dean-Stark unit performs a water removal reaction. The reaction was carried out at boiling temperature for 12 hours. At the end of the reaction, Toluene was removed to room temperature. NaBH4 was added to the three-necked flask in portions, and the reaction was stirred at room temperature for 24 hours. After the reaction was completed, the solution was dropped into deionized water to obtain white. The powder was precipitated, suction filtered and the cake was dried to give white powder (II-D) 32.2 g, yield 92%.

Then, 10.0 g (0.0142 mol) of monomer (II-D) was dissolved in Toluene, and 1.37 g (0.0454 mol) of Paraformaldehyde was placed in a three-neck reaction flask, and reacted at boiling temperature for 24 hours. The filtrate Toluene was drained using a rotary concentrator to give a pale yellow powder (ID) of 10.291 g, yield 99%. Please refer to FIG. 2, which is a schematic diagram of 1H NMR of the I-D compound.

According to another embodiment of the present invention, the method of preparing a phosphorus-containing bifunctional Benzoxazine can be represented by the second scheme, and the second embodiment is illustrated in the following specific examples.

Synthesis Example 5: Synthesis of Compound (V-A)

Take the phosphorus diamine monomer (VIII-A) 30.53 g (0.05 mol), 2-hydroxybenzaldehyde 12.82 g (0.105 mol) dissolved in DMAc/Toluene, stir in a three-neck reaction flask and set up Dean - The Dean-Stark unit performs a water removal reaction. The reaction was carried out at boiling temperature for 12 hours. At the end of the reaction, the Toluene was removed to room temperature. NaBH _{4 was} added to the three-necked flask in portions, and the reaction was stirred at room temperature for 24 hours. After the reaction was completed, the solution was dropped into deionized water. The white powder was precipitated, suction filtered, and the filter cake was dried to white powder (VI-A) 38.26 g, yield 93%.

Then, 10.0 g (0.012 mol) of monomer (VI-A) was dissolved in Toluene, and 1.16 g (0.0388 mol) of Paraformaldehyde was placed in a three-neck reaction flask, and reacted at boiling temperature for 24 hours. The filtrate Toluene was drained using a rotary concentrator to give a pale yellow powder (VA) 10.084 g, yield 98%.

The features and spirit of the present invention will be more apparent from the detailed description of the preferred embodiments. On the contrary, the intention is to cover various modifications and equivalents within the scope of the invention as claimed. Therefore, the scope of the patented scope of the invention should be construed as broadly construed in the

Figure 1 is a schematic diagram showing the 1H NMR of the I-A compound.

Figure 2 is a schematic diagram showing the 1H NMR of the I-D compound.

Claims (2)

A phosphorus-containing bifunctional Benzoxazine resin having a structure of the formula (I): Wherein R1 to R3 are each selected from the group consisting of a hydrogen atom, a C1 to C6 alkyl group, a C3 to C6 cycloalkyl group, and a phenyl group, and when R1 is CH3 or C6H5, R2-R3 may not be H. A phosphorus-containing bifunctional Benzoxazine resin having a structure of the formula (V): Wherein R4 is one selected from the group consisting of C1 to C6 alkyl groups, C3 to C6 cycloalkyl groups, and phenyl groups.