TW201625705A - Low Dk phosphorous containing hardener useful for halogen free, flame retardant polymers and use - Google Patents

Abstract

The average value of n are 0~2, the average value of m are 0~1, the average value of y are 1~2, the average value of x are 1~10.

Description

Low dielectric phosphorus-containing flame retardant hardener and application thereof

The invention relates to a novel low dielectric halogen-free phosphorus-containing phenolic resin compound, which is applied to a glass fiber laminate, exhibits good flame retardancy, low dielectric and heat resistance, and is suitable for use in high performance printed circuit boards. .

In the past, in the epoxy resin flame retardant technology, when the epoxy resin was synthesized or formulated into an epoxy resin composition to introduce or add a halogen compound (such as tetrabromobisphenol A) to impart flame retardant properties, the bromine-containing epoxy resin has excellent properties. Flame-retardant properties, it is widely used in electronic materials requiring flame retardant properties, but the use of halogen flame retardants during combustion will release hydrogen bromide, tetrabromodiphenyl dioxin and tetrabromodibenzifur Sexual and toxic carcinogens have been banned by environmental regulations. From the perspective of environmental protection, today's phosphorus flame retardant systems are the better choice.

In recent years, a phosphorus-containing ring synthesized using a phenanthrene-containing phosphorus compound such as 3,4,5,6-dibenzo-1,2-oxophosphine-2 oxide (hereinafter abbreviated as DOPO) or ODOBP Oxygen resin is widely used in the production of halogen-free FR-4 copper-clad glass fiber laminates. Generally, the phosphorus content of the phosphorus-containing epoxy resin is 2.5% to 3.5%, and the phosphorus content is 1.8% to 2.7%. The flammability can reach UL94 V-0 (when the formula contains flame retardant substances such as phenolic resin, nitrogenous substances, etc., the phosphorus content can be lower). Phosphorus-containing epoxy resin is a reactive flame retardant. Halogen-free copper clad laminates made of it have good comprehensive performance, but with the environmental regulations such as ROHS and POHS, the lead-containing environmental hazard substances are banned, making printed electricity. Road board assembly needs to increase the soldering temperature. Therefore, the flame retardant polymer with high heat resistance, thermal stability, low hygroscopicity and high adhesion is expected to be increasingly added to the upstream material, and the formulation system using phenolic resin as the hardener is expected. It has excellent heat resistance and has been used in the lead-free process of printed circuit boards. The phenolic resin hardener accounts for about 20~40% of the formula weight, which results in insufficient phosphorus content and flame retardancy in the formulation of phosphorus-containing epoxy resin. Insufficient problem, in order to solve the above problems, the introduction of more phosphorus content in the synthesis reaction ensures flame retardancy, which in turn leads to an increase in molecular weight and a decrease in the density of hardened bridging, insufficient Tg of the hardened product, deterioration of thermal properties, and inability to meet the requirements of printed circuit boards. .

Recently, a novel technique for producing a phosphorus-containing phenolic resin hardener having a high phosphorus content has been gradually proposed to solve the above problems. The phosphorus-containing phenolic resin hardener is substituted into a glass fiber laminate to have a high Tg, excellent flame retardancy and heat resistance, but due to electrons. The high-frequency signal transmission of products requires faster transmission speed, and the continuous improvement of the low dielectric properties of the phosphorus-containing phenolic resin hardener is an important issue in the future.

With the development of high-speed and high-speed electronic products, and compliance with environmental regulations, the requirements for the ban on lead, halogen and other environmentally hazardous substances have led to an increase in the temperature of printed circuit board (PCB) assembly reflow, and the temperature increase is more rigorous for material reliability. And the high-frequency signal transmission of electronic products requires faster transmission speed, and the raw materials such as glass laminates on the upstream of printed circuit boards are required to have better heat resistance, low dielectric constant, halogen-free flame retardant properties, and phenolic resin novolac It is a resin formulation of hardener with excellent heat resistance and low water absorption. It has gradually become a formulation system trusted by lead-free processes. It is compatible with the production of halogen-free, lead-free process, low dielectric glass laminates, low dielectric. Phosphate-containing phenolic hardeners are new trends and issues in the future.

In order to solve the above problems, an object of the present invention is to provide a novel phosphorus-containing resin hardener which is excellent in flame retardancy, heat resistance and low dielectric constant suitable for a lead-free process of a PCB, and which is substituted into a glass fiber laminate made of a formulation. It meets UL-94V0 flame retardant requirements, dielectric constant of 4.0 (1GHz), after PCT 2hr water absorption by pressure cooker, 288 °C solder heat resistance for more than 10 minutes does not explode.

The novel low dielectric phosphorus-containing flame retardant phenolic hardener has a molecular structure such as the following chemical formula: Wherein n is the average value 0 to 2; m is the average value 0 to 1; y is the average value 0 to 2; and x is the average value 1 to 10.

The molecular structure design direction of the novel phosphorus-containing flame retardant phenolic hardener compound is to separate the phosphorus compound DOPO from the low dielectric compound 2,6 dimethyl phenol and the nitrogen compound melamine (the nitrogen and phosphorus synergistic effect is better). Branched on bisphenol A and bisphenol A phenolic resin polymer to produce excellent low dielectric properties and flame retardant effects.

The preparation method of the low dielectric phosphorus-containing flame retardant phenolic curing agent: Step (1): reacting 2,6-dimethylphenol with formaldehyde in the presence of a basic catalyst to form a phenolic resin compound resol. Step (2): further adding 2,6-dimethylphenol phenolic resin compound resol to bisphenol A under an acidic catalyst, and reacting with bisphenol A to prepare bisphenol A grafted 2,6-dimethyl Phenolic resin Novolac. Step (3), the obtained (2) is reacted with an aldehyde compound into a phenolic resin compound resol in the presence of a basic catalyst, and the phenolic resin compound resol is dissolved in a solvent, and continuously added to the DOPO, and the active hydrogen of the DOPO is extremely easy. Dehydration with the -CH2-OH group of the phenolic resin compound resol to form DOPO grafted to bisphenol A-2,6-dimethylphenol resin Novolac (abbreviated as BDPD). Step (4) Finally, a melamine aldehyde compound (High lmino-NH Melamine-Formaldehyde Resin, Allnex product name CYMEL-327) is added to the compound BDPD obtained in the step (3), and the melamine aldehyde compound reacts with the CH2-OH of the remaining resol of the BDPD.低Invented low dielectric phosphorus-containing flame retardant hardener (BDPDM for short). The reaction equation is as follows:

The low dielectric phosphorus-containing flame retardant hardener prepared according to the core of the invention has a high molecular structure and a low molecular even pitch characteristic introduced into the chemical molecular structure of 2,6 dimethylphenol and 2,6 dimethylphenol. The hydrophobic group has a lower dielectric constant than the general phenolic novolac hardener.

The phosphorus-containing flame retardant hardener of the present invention can be used for various applications, including insulating materials for high reliability motor/electronic components such as PCB printed circuit boards, EMC semiconductor packages, and coatings requiring excellent flame retardancy and heat stability. , adhesive.

FIG 1: a low dielectric phosphorous containing phenolic resin hardener ¹ H NMR spectrum ⁽¹ HNMR) disclosed in the present invention, the compounds were dissolved in _{DMSO-d 6 (DMSO-d} 6 Chemical shift chemical shiftδ = 2.48).

1. Chemical shift chemical shift δ 0.7~1.5 is the absorption of bisphenol A structure CH ₃ -C-CH ₃ .

2. Chemical shift chemical shift δ 1.9~2.1 is the absorption of Ph 2 CH ₃ structure.

3. Chemical shift chemical shift δ 3~3.8 is P-CH ₂ -Ph and Ph-CH ₂ -Ph absorption.

4. Chemical shift chemical shift δ 6.4~8 is the absorption of Ph-H.

5. Chemical shift chemical shift δ 9~9.3 is the absorption of Ph-OH.

6. Chemical shift chemical shift δ 6.2~6.4 is the absorption of N-H.

The invention will be more clearly understood from the following detailed description.

The most striking feature of the novel low dielectric phosphorus-containing hardener at the core of the present invention is the co-grafting of bisphenol A (ie, BPA) with 2,6-dimethylphenol (ie, 2,6 DMP) and melamine (ie, melamine). Phosphate phenolic hardener, which has high chemical structure and high-density benzene ring, polyfunctional phenolic phenolic group, and phosphorus-nitrogen flame retardant synergistic effect, so it has excellent flame retardancy, heat resistance and low Dielectric properties, the phosphorus content of the low dielectric phosphorus-containing hardener ranges from 5 to 9.5%, preferably from 6 to 9.5%, and the nitrogen content is from 0 to 2%.

Specifically, the method for preparing the core low dielectric phosphorus-containing hardener of the present invention comprises the step (1) of reacting 2,6-dimethylphenol with formaldehyde in the presence of a basic catalyst to form a phenolic resin compound resol. Step (2), further adding 2,6-dimethylphenol phenolic resin compound resol to bisphenol A under an acidic catalyst, and reacting with bisphenol A to prepare bisphenol A grafted 2,6-dimethyl Phenolic resin Novolac (BDP for short). Step (3), the obtained (2) is reacted with an aldehyde compound into a phenolic resin compound resol in the presence of a basic catalyst, and the phenolic resin compound resol is dissolved in a solvent, and continuously added to the DOPO, and the active hydrogen of the DOPO is extremely easy. Dehydration with the CH2-OH group of the phenolic resin compound resol to form DOPO grafted to bisphenol A-2,6 dimethylphenol resin Novolac (abbreviated as BDPD). Step (4) Finally, the melamine aldehyde compound (High lmino-NH Melamine-Formaldehyde Resin, Allnex product name CYMEL-327) is added to the compound BDPD obtained in the step (3), and the reaction of the melamine aldehyde compound with the CH2-OH of the remaining resol of BDPD is低Invented low dielectric phosphorus-containing flame retardant hardener (BDPDM for short). The specific chemical reaction formula for preparing the core low dielectric phosphorus-containing hardener of the present invention is as follows:

The method for preparing the low dielectric phosphorus-containing hardener of the present invention is described in more detail, and the steps (1) to (4) are as follows, in order to obtain the phenolic phenolic grafted on the bisphenol A with 2,6-dimethylphenol. Resin novolac, step (1) a. First react with formaldehyde under 2,6-dimethylphenol under a basic catalyst to form a phenolic resin compound resol. Wherein 2,6-dimethylphenol and aldehyde are reacted in a relative molar ratio of 1:1 to 1:5, and the reaction can be conducted at 30 to 70 ° C for 20 minutes to 5 hours, preferably 2, 6 Dimethylphenol and aldehyde are reacted in a relative molar ratio of 1:3 to 1:4, and the reaction temperature is 30 to 50 ° C, and the reaction time is 20~40 minutes. At the same time, the 2,6-dimethylphenol phenolic resin compound resol is less hydrophilic than the general phenolic resin compound resol, so it is easy to dissolve the 2,6-dimethylphenol phenolic resin compound resol with a solvent such as methyl isobutyl ketone (MIBK). The mixture is neutralized and washed with water to remove the residual alkaline catalyst and residual aldehyde in the water layer, thereby obtaining a high yield, and is not dissolved in water like the general phenolic resin compound resol, and the yield is low. The basic catalyst is not particularly limited as long as it is used in a resol reaction of a phenol resin compound, and comprises a basic catalyst selected from commercially available, such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate and an amine, and alkaline. The amount of catalyst used is 1 to 5% of the amount of polyoxymethylene (92%).

Step (2) Further, 2,6-dimethylphenol phenolic resin compound resol is added dropwise to bisphenol A under an acidic catalyst to graft it with bisphenol A. The 2,6-dimethylphenol phenolic resin compound resol is added dropwise to the BPA containing the acid catalyst, and the 2,6-dimethylphenol phenolic resin compound resol is a single reactive group, which can be easily controlled and doubled in this way. The ratio of phenol A grafting to avoiding the self-polymerization of phenolic resin compound resol leads to excessive molecular weight (2,6-dimethylphenol phenolic resin compound resol self-polymerization is only dimer dimer), resulting in poor surface defects of glass film laminate processing prepreg The physical properties of the hardened product are drastically degraded. On the other hand, if the bisphenol A is first reacted under a basic catalyst to react the BPA phenolic resin compound resol to the 2,6 dimethylphenol reaction, since the one molar BPA has a four molar reaction group, the BPA phenolic resin compound Resol is a plurality of reactive groups, and the self-polymerization reaction inevitably causes the molecular weight to be too large, resulting in an unintended side reaction, resulting in undesirable results. The acidic catalyst used in the step (2) may comprise a commercially available acidic catalyst such as oxalic acid, methanesulfonic acid (MSA), p-toluenesulfonic acid (PTSA), sulfuric acid, hydrochloric acid, phosphoric acid or the like.

In this step (2), in order to avoid self-polymerization of the 2,6-dimethylphenol phenolic resin compound resol, the 2,6-dimethylphenol phenolic resin compound resol should be slowly added dropwise to the bisphenol A, wherein 2,6-dimethyl The phenol phenolic resin compound resol reacts with bisphenol A in a relative molar ratio of 1:1 to 2:1. The reaction can be carried out in the MIBK solvent system at 80-120 ° C for 2-6 hours, and the amount of acid catalyst is bisphenol. A dosage is 0.5%~2%.

Step (3) grafting BPA with a phenolic resin product of 2,6-dimethylphenol resol (abbreviated as BDP), and reacting with an aldehyde in the presence of a basic catalyst to form a phenolic resin compound resol, which is preferably selected as a basic catalyst. It is a low-boiling amine. After the reaction is completed, it is removed with water by vacuuming, thereby removing residual amine and residual aldehyde of water layer, and the temperature is controlled to <75 ° C to reduce resol self-polymerization. If NaOH is used as the catalyst, acid neutralization is required to produce sodium salts. Subsequent removal of the sodium salt by water washing may cause some products to be dissolved in water, and the organic layer and the water layer may not be layered by water. The problem of low product yield is caused by the method that the BPA grafted 2,6-dimethylphenol has a phenolic resin (BDP) to aldehyde molar ratio of 1:1 to 1:3, the reaction temperature is 40-80 ° C, and the reaction time is low. 1~6 hours, the yield is >99%, and the amount of alkaline catalyst is 1~5% of the amount of polyoxymethylene (92%).

The phenolic resin compound resol obtained in the step (3) is dissolved in the solvent propylene glycol monomethyl ether PM, and then added dropwise to the DOPO to react with DOPO to form a low dielectric phosphorus-containing hardener (abbreviated as BDPD). The phenolic resin compound resol (abbreviated as BDR) obtained in the step (3) is gradually added dropwise to the DOPO reaction, and the phenolic resin resol (BDR) and the DOPO molar ratio of the BPA grafted 2,6-dimethylphenol are 1 :1~1:3, the reaction temperature is controlled at 135~145 °C. During the dropwise addition reaction, the water produced by the reaction is immediately taken out because it is higher than the boiling point of water, because if water is present, The phenolic resin compound resol reacts slowly with DOPO, and does not react with DOPO, but causes a side reaction of self-polymerization of the phenolic resin compound resol, resulting in residual unreacted phosphorus-containing compound, leaving relatively low flame retardancy, physical properties, and target. The yield of the flame retardant hardener is low and the like. In order to reduce the above side reaction, the obtained phenolic resin compound resol is gradually added dropwise to the DOPO, and the concentration of the phenolic resin compound resol and water in the reaction system can be kept low by the dropping method, thereby reducing the phenolic resin compound resol Self-polymerization side reaction, the reaction time is added dropwise for 2 to 6 hours.

Step (4) When the reaction of step (3) is finished, the residual DOPO is analyzed <0.1% (GPC gel chromatography analysis), and finally the melamine aldehyde compound (High lmino-NH) Melamine-Formaldehyde Resin, ALLNEX product name CYMEL-327) was added to the compound BDPD obtained in the step (3) at 145 ° C, and the melamine aldehyde compound was reacted with the CH2-OH of the BDPD residual resol, and the melamine was grafted onto the BDPD compound to form the present. Inventing a low dielectric phosphorus-containing hardener, the melamine aldehyde compound and bisphenol A are reacted in a relative molar ratio of 0.05:1 to 0.5:1 for 1 to 2 hours, and the temperature is continuously increased to 185 ° C for 30 minutes to 1 hour. The unreacted CH2-0H group is completely reacted, and the low dielectric phosphorus-containing hardener has a phosphorus content ranging from 5 to 9.5%, preferably from 6 to 9.5%. The nitrogen content is 0~2%.

Preferred embodiments of the invention will be described in detail in accordance with the following examples.

Example 0 Synthesis of low dielectric phosphorus-containing hardener of the present invention:

(1) 2,6-dimethylphenol phenolic resin compound resol synthesis: 121.5 g (1 mol) 2,6-dimethylphenol, 97.2 g 92% paraformaldehyde (3 mol), 800 g pure water, 5.7 g 49.5% aqueous sodium hydroxide solution was placed in a 1000 ml reaction vessel, and reacted at 45 ° C for 20 minutes with heating and stirring. Then, it was neutralized by adding 30 g of 10% sulfuric acid aqueous solution, dissolved in 230 g of MIBK solvent, and the aqueous layer was drained, and then washed twice with 200 g of pure water, and the MIBK layer was taken to obtain 2,6-dimethylphenol phenolic resin compound resol. A total of 440 g of the MIBK solution was obtained in a yield of 80% (analyzed by HPLC high-efficiency liquid chromatography) to obtain a 2,6-dimethylphenol phenolic resin compound resol 0.75 mol.

(2) bisphenol A grafting 1 molar 2,6 dimethyl phenol phenolic resin (abbreviated as BDP) synthesis: bisphenol A 228g (1 mole) dissolved in 250g MIBK solution to 115 ° C, the temperature reached 115 ° C 2.1 g of 70% methanesulfonic acid, and the MIBK solution of the obtained 2,6-dimethylphenol phenolic resin compound resol of (1) was added dropwise to the MIBK solution of the above bisphenol A by a quantitative pump, and the dropping time was 6 hours. After the reaction was completed, 1.27 g of 49.5% NaOH was added to neutralize and 100 g of water was added at the same time. After stirring at 75 ° C for 10 minutes, the liquid layer was allowed to stand for separation, and the lower aqueous layer was drained. The upper organic phase was further added with 100 g of water at 75. ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° organic The layer was placed on a rotary evaporator at 175 ° C × 5 torr for 3 hours, and the solvent MIBK and the residual 2,6 dimethylphenol were removed to obtain 1 gram of bisphenol A grafted with 0.75 mole of 2,6 dimethylphenol phenol. The resin (abbreviated as BDP) had a total of 313.5 g and a yield of 95%.

(3) Synthesis of phenolic resin resol compound (abbreviated as BDPR) of bisphenol A grafted with 2,6-dimethylphenol: Weigh the above steps (2) bisphenol A grafted 2,6-dimethylphenol (BDP), plus 300g water, add 92% paraformaldehyde 97.8g (3 moles) plus catalyst triethylamine 15g, react at 60 ° C for four hours, after the end of the reaction, gradually reduce the vacuum to 10torr, the temperature of 75 ° C to remove water and three Ethylamine, when the temperature reached 75 ° C, propylene glycol monomethyl ether PM 180g was dissolved to obtain phenolic resin resol compound (abbreviated as BDPR) of bisphenol A grafted 2,6 dimethylphenol 400g, the yield was 99.5%.

(4) bisphenol A grafted 2,6 dimethylphenol phosphorus-containing phenolic resin (abbreviated as BDPD) synthesis: DOPO 626g (2.9 moles) was placed in the reaction tank, heated to 140 ° C to dissolve DOPO, and the steps ( 3) bisphenol A grafted 2,6 dimethylphenol phenolic resin resol compound (abbreviated as BDPR) was added dropwise to the reaction tank by quantitative pump, the reaction time was added dropwise for 4 hours, and the temperature was raised to 145 ° C after the completion of the dropwise addition reaction. The ripening reaction was carried out, the ripening reaction time was 2.5 hours, and the residual dopo was analyzed to be about 0.2%, that is, 991 g of a phosphorus-containing phenolic resin (abbreviated as BDPD) of bisphenol A grafted with 2,6-dimethylphenol was obtained, and the yield was 100%.

(5) Synthesis of bisphenol A grafted 2,6-dimethylphenol and melamine-containing phosphorus phenolic resin (abbreviated as BDPDM): followed by step (4), analysis of phosphorus content of bisphenol A grafted 2,6-dimethylphenol Phenolic resin (abbreviated as BDPD) has a dopo residual amount of <0.2%, and a melamine aldehyde compound (methyl etherified melamine and formaldehyde, ALLNEX product name CYMEL-327, 90% solid in butanol) 71.7 g (0.25 m) was added at 145 °C. After reacting for 1 hour, the temperature is raised to 185 ° C for 1 hour, and then the vacuum is depressurized for 30 minutes to remove the solvent PM, etc., thereby obtaining the low dielectric phosphorus-containing phenolic resin hardener of the present invention - bisphenol A grafted 2,6 dimethyl A total of 1032 g of a phosphorus-containing phenolic resin of phenol and melamine (abbreviated as BDPDM) has a phosphorus content of 8.9%, a nitrogen content of 1%, and a yield of 99.5%.

FT-IR results: phenol-hydroxyl group and amine group: 3226 cm ^-1 , P = 0 1197 cm ^-1 /1280 cm ^-1 , POC (aryl group) 921 cm ^-1 /1117 cm ^-1 , PC aryl 1431 cm ^-1 .

¹ H-NMR results: chemical shift δ 0.7~1.5 is the absorption of CH ₃ -C-CH ₃ , chemical shift δ 1.9~2.1 is the absorption of Ph-CH ₃ . The chemical shift of chemical shift δ 3~3.8 is the absorption of P-CH ₂ -Ph and Ph-CH ₂ -Ph. The chemical shift of chemical shift δ 6.4~8 is the absorption of Ph-H. The chemical shift of chemical shift δ 9~9.3 is the absorption of Ph-OH. Chemical shift chemical shift δ 6.2 ~ 6.4 is the absorption of NH.

Example 1~3

The use of the low dielectric phosphorus-containing flame retardant hardener of the present invention for a glass fiber laminate, a Varnish formulation having excellent flame retardancy, heat resistance and low dielectric constant, the formulation composition of which is detailed in the table (a ), using a solvent such as propylene glycol monomethyl ether (PM) or methyl ethyl ketone or acetone to adjust a resin varnish (Varnish) formulation having a solid content of 65%, preparing a glass fiber laminate by a conventional method, and impregnating the 7628 glass fiber cloth The resin liquid is then dried at 170 ° C (the temperature of the impregnation machine) for several minutes. By adjusting the drying time, the minimum melt viscosity of the prepreg after drying can be adjusted to be between 4000 and 10000 poise, and finally the eight prepreg layers are stacked. Control the temperature rise program between two 35-um thick copper foils at a pressure of 25 kg/cm ² : After hot pressing, a 1.6 mm thick copper foil substrate was obtained.

Comparative example 1~2

When the low dielectric phosphorus-containing flame retardant hardener of the present invention is not used, and other flame retardants are used as comparative examples, Comparative Example 1 uses a bromine-based flame retardant TBBA, and Comparative Example 2 uses a general bisphenol A phenolic resin hardener ( Nanya Plastics Co., Ltd. model NPEH-720HA65) and phosphorus epoxy resin, the formulation of which is detailed in Table (2).

It can be seen from the above test results that the glass fiber laminate prepared by substituting the phosphorus-containing low dielectric phenolic hardener of the present invention has a dielectric constant Dk of at least 4.0, and the dielectric constant can be lowered from 4.6 to 4.2 as compared with the comparative example. It shows that the phosphorus-containing low dielectric phenolic curing agent has the effect of lowering the dielectric constant, and is suitable for a printed circuit board for high-frequency high-speed signal transmission.

1. Varnish gel time

The varnish reactivity test is to combine the epoxy resin solution with the hardener dicydiamide solution (dissolved in solvent DMF, solution concentration = 13.3%), the accelerator 2-imidazole (2-phenyl imidazole) or 2-methylimidazole. A (2-methyl imidazole) solution (dissolved in solvent DMF, solution concentration = 14.28%) was used to prepare a varnish mixture. The varnish mixture was dropped to about 0.3 ml on a hot plate, and the hot plate temperature was 170 ° C, and the time required for gelation was recorded.

2. Prepreg gel time

The prepreg test method is that 0.2 mg of the prepreg powder is weighed and placed on a hot plate, and the hot plate temperature is 170 ° C, and the time required for gelation is recorded.

3. Water absorption test (PCT pressure cooker 2 hours)

The water absorption rate test method is to cut the substrate after etching into a 5 cm ² square test piece, and after drying in an oven at 105 ° C for 2 hr, the test piece is placed in a pressure cooker, the pressure cooker condition is 2 atm × 120 ° C, and after passing through the pressure cooker for 120 min, the recording test is performed. The difference in weight before and after the pressure cooker is the water absorption rate at the initial weight of the test piece.

4. 288 ° C solder heat resistance (2 hours via PCT pressure cooker)

The test method is to immerse the above-mentioned pressure cooker test piece in a 288 ° C soldering furnace to record the time required for the test piece to blast.

5. Dielectric constant test: The test method is that a 5 cm×5 cm square test piece of a glass fiber laminate with a ketone foil removed is baked in an oven at 105° C. for 2 hr, and the thickness is measured by a thickness measuring instrument, and then the test piece is sandwiched into a dielectric constant measuring instrument. The data of 3 points was measured and averaged.

6. Dissipation factor test: The test method is that a 5 cm×5 cm square test piece of a glass fiber laminate with a ketone foil removed is baked in an oven at 105° C. for 2 hr, and the thickness is measured by a thickness measuring instrument, and then the test piece is sandwiched into a dielectric constant measuring instrument. The data of 3 points was measured and averaged.

7. Temperature of glass transition test: A differential scanning calorimeter (DSC) was used, and the heating rate was 20 ° C / min.

8. Flame retardant test: The flame retardancy of the sample was tested according to the UL-94 standard method.

Claims (3)

A low dielectric phosphorus-containing phenolic resin hardener having the following structure: Wherein n is the average value 0 to 2; m is the average value 0 to 1; y is the average value 0 to 2; and x is the average value 0 to 10. The preparation method of the low dielectric phosphorus-containing phenolic resin hardener according to claim 1, comprising the following steps (1) to (4): step (1) a. first with 2,6 dimethylphenol The basic catalyst reacts with formaldehyde to form a phenolic resin compound resol, wherein 2,6-dimethylphenol reacts with the aldehyde at a relative molar ratio of 1:1 to 1:5, and the reaction can be guided at 30 to 70 ° C. 20 minutes to 5 hours, preferably 2,6-dimethylphenol and aldehyde are reacted in a relative molar ratio of 1:3 to 1:4, the reaction temperature is 30 to 50 ° C, the reaction time is 20 to 40 minutes, and the alkali is used. The catalyst is not particularly limited as long as it is used in a resol reaction of a phenol resin compound, and contains a commercially available basic catalyst such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate and an amine, and an alkaline contact. The amount of the medium used is 1 to 5% of the amount of polyoxymethylene (92%). The 2,6-dimethylphenol phenolic resin compound resol was dissolved in a solvent methyl isobutyl ketone (MIBK), neutralized, and washed with water to remove residual alkali catalyst and residual aldehyde in the aqueous layer. Step (2) and then 2,6-dimethylphenol phenolic resin compound resol under acidic catalyst It was added dropwise to bisphenol A to be grafted with bisphenol A. The 2,6-dimethylphenol phenolic resin compound resol was added dropwise to the BPA containing the acid catalyst. The acidic catalyst used in the step (2) may comprise a commercially available acidic catalyst such as oxalic acid, methanesulfonic acid (MSA), p-toluenesulfonic acid (PTSA), sulfuric acid, hydrochloric acid, phosphoric acid or the like. The 2,6-dimethylphenol phenolic resin compound resol reacts with bisphenol A in a relative molar ratio of 1:1 to 2:1, and the reaction can be carried out in the MIBK solvent system at 80-120 ° C for 2-6 hours. The amount of acidic catalyst is 0.5%~2% of bisphenol A. Step (3) grafting BPA with a phenolic resin product of 2,6-dimethylphenol resol (abbreviated as BDP), and reacting with an aldehyde in the presence of a basic catalyst to form a phenolic resin compound resol, which is preferably selected as a basic catalyst. As a low-boiling amine, after the reaction is completed, it is removed with water by vacuuming, thereby removing residual amine and residual aldehyde of water layer, and the temperature is controlled to <75 ° C to reduce resol self-polymerization. In this step, BPA grafted 2,6-dimethylphenol has a phenolic resin (BDP) to aldehyde molar ratio of 1:1 to 1:3, a reaction temperature of 40 to 80 ° C, a reaction time of 1 to 6 hours, and a yield of >99. %, the amount of alkaline catalyst is 1~5% of the amount of polyoxymethylene (92%). The phenolic resin compound resol obtained in the step (3) is dissolved in the solvent propylene glycol monomethyl ether PM, and then added dropwise to the DOPO to react with the DOPO to form a low dielectric phosphorus-containing hardener (abbreviated as BDPD), and the BPA is grafted with 2,6 dimethyl The phenolic resin resol (BDR) and DOPO molar ratio of phenol are 1:1~1:3, and the reaction temperature is controlled at 135~145 °C, and the reaction time is 2~6 hours. Step (4) When the reaction of the step (3) is completed, the residual DOPO is analyzed by <0.1% (GPC gel chromatography analysis), and finally the melamine aldehyde compound is added to the compound (BD) of the step (3) at 145 ° C to make the melamine aldehyde compound and BDPD residual resol CH2-OH reaction, melamine grafted BDPD compound to form the low dielectric phosphorus-containing hardener of the present invention, melamine aldehyde compound and bisphenol A reacted in a relative molar ratio of 0.05:1 to 0.5:1 1~2 hours, continue to increase the temperature to 185 ° C for 30 minutes to 1 hour, the unreacted CH2-0H group is completely reacted, the low dielectric phosphorus-containing hardener has a phosphorus content ranging from 5 to 9.5%, preferably 6 To 9.5 %. The nitrogen content is 0~2%. An epoxy resin varnish composition for a glass laminate comprising the following components: (i) a dicyclopentadiene-phenol polyfunctional epoxy resin (DCPD polyfunctional epoxy resin) or any other polyfunctional phenolic epoxy resin Resin), the amount of use accounts for 10 to 70% of the total amount of the resin (the total amount of resin is equal to the sum of the components 1 to 4). (2) 2,6-dimethylphenol aldehyde difunctional epoxy resin or any other bifunctional epoxy resin, the amount of which is 0 to 30% of the total amount of the resin. (3) Hardener 1: The phenolic resin hardener or the bisphenol A type phenolic resin hardener, the amount of use accounts for 0~30% of the total amount of the resin. (4) Hardener 2: The novel low dielectric phosphorus-containing hardener of the present invention is used in an amount of 10 to 40% of the total amount of the resin. (5) Filler: It can be cerium oxide, aluminum hydroxide, etc., and the amount used is 0~45% of the total formulation varnish. (6) It is an appropriate amount of hardening accelerator and solvent, wherein the hardening accelerator may be imidazole, quaternary amine, and quaternary phosphonium salt, and dimethylimidazole, diphenylimidazole, etc. are more commonly used, and a suitable accelerator The amount used is 0.01 to 0.2 phr (without the epoxy resin main agent, no hardener is included). The solvent may be a ketone, an ether alcohol or the like, such as acetone, methyl ethyl ketone, cyclohexanone, dimethoxyethanol (MCS), propylene glycol methyl ether (PM), etc., and a suitable solid content of 55 to 70%.