Bisphenol A-based six-functional-group resin / glass fiber / diethylenetriamine composite material as well as preparation method and application thereof

Abstract

The invention discloses a bisphenol A-based hexa-functional-group resin / glass fiber / diethylenetriamine composite material and a preparation method and application thereof, and belongs to the technical field of epoxy resin composites.The preparation method includes the steps that bisphenol A and formaldehyde are heated and stirred to be uniform, then epoxy chloropropane and a NaOH aqueous solution are added, the mixture is heated and stirred to be uniform, then methyl ethyl ketone is added, desalting is conducted, and the bisphenol A-based hexa-functional-group resin / glass fiber / diethylenetriamine composite material is obtained; the preparation method comprises the following steps: mixing bisphenol A-based hexa-functional-group resin and diethylenetriamine, distilling the resin to obtain bisphenol A-based hexa-functional-group resin, uniformly mixing the bisphenol A-based hexa-functional-group resin and diethylenetriamine, coating a plurality of glass fibers with the mixture, and performing high-temperature curing, pressing and cooling to obtain the bisphenol A-based hexa-functional-group resin / glass fiber / diethylenetriamine composite material. The bisphenol A-based hexa-functional-group resin is crosslinked with diethylenetriamine, so that the molecular chain of the epoxy resin is tighter, a stable crosslinked structure is formed, the curing efficiency is improved, and the product has higher hardness and glass transition temperature. The glass fiber is doped, so that the mechanical property of the epoxy resin is remarkably improved.

Description

Technical Field

[0001] The invention belongs to the technical field of epoxy resin composite materials, and specifically relates to a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material and a preparation method and application thereof. Background Art

[0002] With the continuous growth of global electricity demand and the rapid development of long-distance, large-capacity, high-voltage direct current (HVDC) technology, the trend of miniaturization and integration of electronic and electrical equipment is becoming increasingly significant, which puts forward more stringent physical performance requirements for insulating materials. Insulating materials need to have excellent electrical insulation, thermal stability and mechanical strength to adapt to high voltage, high temperature and complex stress environments. However, while existing insulating materials meet these requirements, they still face many challenges, such as performance balance and long-term stability. It is urgent to break through these limitations through material modification to promote the further development of electronic and electrical equipment technology.

[0003] In the pursuit of high-performance insulating materials, epoxy resins have occupied an important position in the field of fiber-reinforced composites due to their excellent heat resistance, good adhesion and mechanical properties. The performance optimization of epoxy resins is inseparable from the careful design of their network structures, and the characteristics of the network structures are deeply affected by the functionality of epoxy resins. Improving the functionality of epoxy resins, especially increasing their functionality, has become an effective way to achieve high-strength and high-modulus epoxy resin systems. Multifunctional epoxy resins have therefore emerged and have attracted much attention for their enhanced mechanical, chemical, thermodynamic and electrical properties, while showing high glass transition temperatures, excellent decomposition temperature stability, long-term high-temperature service capabilities and good wet strength retention. However, despite the many advantages of multifunctional epoxy resins, their inherent defects such as high brittleness and easy hygroscopicity cannot be ignored. These limitations become more prominent with the increase of network crosslinking density, posing a severe challenge to the overall physical and mechanical properties and long-term service life of the material. Current research focuses on adjusting the type and structure of epoxy resin functional groups to explore their effects on the dynamic, mechanical and fracture properties of materials, in order to find the best solution to balance performance and defects.

[0004] In order to further improve the comprehensive performance of epoxy resin, researchers have tried to incorporate reinforcing materials such as glass fiber into it to form epoxy-based fiber composite materials. Although the mechanical properties and corrosion resistance have been improved to a certain extent, more innovative solutions are still needed to address the fundamental problems of the brittleness and low glass transition temperature of the multifunctional epoxy resin itself. Therefore, developing a new epoxy resin formula that can maintain strong electrical properties without sacrificing mechanical strength after curing, and achieving optimal matching of the main agent and the curing agent has become a technical problem that needs to be solved urgently in order to achieve the optimization of overall performance. Summary of the invention

[0005] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material and a preparation method and application thereof, so as to solve the technical problems of inherent brittleness, low glass transition temperature, weak physical and mechanical properties and short service life of existing multifunctional epoxy resins.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: The invention discloses a preparation method of a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material. The method comprises the following steps: heating and stirring bisphenol A and formaldehyde evenly, adding epichlorohydrin and a NaOH aqueous solution, heating and stirring evenly, adding methyl ethyl ketone, desalting and distilling the resin to obtain a bisphenol A-based hexafunctional resin, then mixing the bisphenol A-based hexafunctional resin and diethylenetriamine evenly and coating the mixture on a plurality of glass fibers, and curing at high temperature, pressing and cooling the mixture to obtain a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material.

[0007] Preferably, the usage ratio of bisphenol A: formaldehyde: epichlorohydrin: NaOH aqueous solution: methyl ethyl ketone is (0.8-1.2) mol: (4-6.5) mol: (3-5) mol: (2-4) mol: (50-100) mL; the mass fraction of the NaOH aqueous solution is 40%.

[0008] Preferably, the heating and stirring temperature is 55-70°C and the time is 2-4h.

[0009] Preferably, the temperature of heating and stirring is 70-90° C., and the time is 3-4 hours.

[0010] Preferably, the temperature of the distilled resin is 118° C., and the time of the distilled resin is 3-4 hours; the reaction yield of the bisphenol A-based hexafunctional resin is 76%-82%.

[0011] Preferably, the molar ratio of bisphenol A-based hexafunctional resin: diethylenetriamine: glass fiber is (45-55): (53-64): (8-12).

[0012] Preferably, the high temperature curing temperature is 70-85° C. and the high temperature curing time is 2-4 h.

[0013] Preferably, the pressing pressure is 50-60 psi; the pressing temperature is 85-90° C.; and the pressing time is 2-10 min.

[0014] The invention also discloses a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material prepared by the preparation method, which has a tensile strength of 64.8-68.4 MPa, a flexural strength of 142.5-146.6 MPa, an impact strength of 4.12-4.75 J / cm, and a glass transition temperature of 159-162°C.

[0015] The invention also discloses the use of the bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material prepared by the preparation method in the preparation of electronic component materials and insulating packaging materials.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The invention discloses a preparation method of a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material; by controlling the temperature, methyl ethyl ketone is removed at 79.6°C, water is removed at 100°C, and epichlorohydrin impurities are removed at 117.9°C, thereby obtaining a bisphenol A-based hexafunctional resin; the resin has multiple functional groups, and can react with glass fiber and diethylenetriamine to form a stable cross-linked structure, thereby improving the performance of the composite material. The bisphenol A-based hexafunctional resin and diethylenetriamine are uniformly mixed and coated on a number of glass fibers; by mixing the bisphenol A-based hexafunctional resin and diethylenetriamine, the reaction activity and cross-linking density of the resin can be increased, thereby improving the mechanical properties and chemical stability of the composite material. Coating on glass fibers can make full use of the high strength and high modulus characteristics of glass fibers and enhance the overall performance of the composite material; after high-temperature curing, pressing, and cooling, a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material is obtained; high-temperature curing can promote the cross-linking reaction of the functional groups in the resin to form a stable network structure, thereby improving the heat resistance and dimensional stability of the composite material. At the same time, the curing process can also eliminate the residual stress and bubbles in the material, improve the microstructure and performance of the material; the pressing process can make the fibers and resins in the composite material more closely combined, reduce pores and defects, and improve the density and mechanical properties of the composite material. In addition, pressing can also make the composite material obtain the desired shape and size. The cooling process can fix the shape and size of the composite material, while reducing the residual stress and deformation of the material. The obtained composite material has excellent mechanical properties, chemical stability and heat resistance, and can be widely used in aerospace, automobile, electronics and other fields. Bisphenol A-based hexafunctional resin is prepared by polymerization reaction of bisphenol A, formaldehyde and epichlorohydrin under alkaline medium conditions; this synthesis method can introduce multiple functional groups, so that the resin has higher reactivity and cross-linking ability. At the same time, bisphenol A as a raw material gives the resin excellent heat resistance and chemical stability. This resin, as the matrix of the composite material, can significantly improve the overall performance of the composite material.

[0017] The present invention also discloses a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material obtained by the above-mentioned preparation method; in terms of mechanical properties, the composite material exhibits good tensile and bending resistance, and its tensile strength range reaches 64.8-68.4MPa. This data not only indicates the stability of the material under tensile load, but also reflects the compactness and uniformity of its internal structure, ensuring the high efficiency and continuity of stress transfer. At the same time, the bending strength is as high as 142.5-146.6MPa, which highlights the excellent load-bearing and deformation resistance of the material under complex stress states, and provides a solid foundation for the lightweight and high-strength design of structural parts. In terms of impact toughness, the composite material also performs well, and its impact strength range reaches 4.12-4.75J / cm. This indicator not only reflects the excellent absorption and dispersion ability of the material to sudden impact loads, but also reveals the close interface bonding between its internal fibers and the matrix, effectively preventing the initiation and expansion of cracks, thereby significantly improving the overall toughness and damage resistance of the material. The composite material also exhibits excellent thermal stability, with a glass transition temperature of up to 159-162°C. This feature not only means that the material can maintain stable physical and chemical properties in high temperature environments and is not prone to thermal degradation or performance degradation, but also provides a strong guarantee for its long-term stable operation under extreme temperature conditions. The high glass transition temperature characteristic gives the composite material significant advantages in applications in high temperature environments such as aerospace, automobile manufacturing, and electronic appliances. In addition, the preparation process of the composite material also has good controllability and repeatability, which makes large-scale industrial production possible. Its unique component design and preparation technology not only optimizes and improves material performance, but also provides broad space for subsequent material modification and function expansion.

[0018] The present invention also discloses the application of the bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material prepared by the above-mentioned preparation method in the preparation of electronic component materials and insulating packaging materials; in terms of electronic component materials, the composite material provides solid physical support for electronic components by virtue of its excellent mechanical properties. Its high tensile strength and flexural strength ensure that the components can maintain structural integrity when subjected to external forces, and are not prone to deformation or cracking, thereby improving the reliability and service life of the components. At the same time, the high glass transition temperature of the composite material gives the components excellent thermal stability, enabling them to work for a long time in a high temperature environment without performance degradation, which is crucial for improving the overall performance and stability of electronic equipment. In addition, the excellent electrical insulation performance of the composite material effectively isolates the interference of current on components, ensures the accurate transmission of electronic signals, and improves the electrical performance of components. In terms of insulating packaging materials, the application of the composite material is also outstanding. Its excellent insulation performance can effectively prevent the leakage of current in the packaging structure and protect the internal electronic components from the threat of safety hazards such as electric shock or short circuit. At the same time, the good processability of the composite material makes the packaging process simpler and more efficient, and can form a tight and uniform packaging layer, effectively isolating the components from the external environment and extending the service life of the electronic components. In addition, the high strength characteristics of the composite material also enhance the mechanical strength of the packaging structure, enabling it to better resist external shocks and vibrations, providing more reliable protection for electronic components. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The schematic diagram of the preparation of the bisphenol A-based hexafunctional resin of the present invention; Figure 2 FT-IR spectra of the bisphenol A based hexafunctional resin and industrial epoxy resin prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0021] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0022] The present invention is described below with reference to specific examples. It will be appreciated by those skilled in the art that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention in any way.

[0023] The experimental methods in the following examples are conventional methods unless otherwise specified. The raw materials, reagents, etc. used in the following examples are commercially available products unless otherwise specified.

[0024] The present invention is further described in detail below in conjunction with the accompanying drawings: The present invention discloses a method for preparing a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material; comprising: placing a 2L three-necked flask equipped with a mechanical stirrer and a condenser in a constant temperature heating device. Under alkaline conditions, 0.8-1.2 mol of bisphenol A and 4-6.5 mol of formaldehyde are added to the flask. Stir at a temperature of 55-70°C for 2-4 hours, then add 3-5 mol of epichlorohydrin to the reaction flask, and drop a NaOH aqueous solution (2-4 mol, mass fraction of 40%). After the addition is completed, the temperature is raised to 70-90°C, the reaction mixture is stirred for 3-4 hours, and then 50-100 mL of methyl ethyl ketone is added as a solvent to maintain the viscosity of the resin. Desalination is carried out by vacuum distillation, and then the resin is distilled at 118°C for 3-4 hours to remove excess water, methyl ethyl ketone and epichlorohydrin, and cooled at room temperature to obtain a dark yellow, odorless bisphenol A-based hexafunctional resin with a yield of 76%-82%. The reaction principle is as follows Figure 1As shown. Bisphenol A-based hexafunctional resin and diethylenetriamine are mixed evenly and coated on a number of glass fibers. After high-temperature curing, pressing and cooling, a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material is obtained; the bisphenol A-based hexafunctional resin is prepared by polymerization of bisphenol A, formaldehyde and epichlorohydrin under alkaline medium conditions. Among them, the molar ratio of bisphenol A-based hexafunctional resin: diethylenetriamine: glass fiber is (45-55): (53-64): (8-12). The performance of the composite material can be optimized by precisely controlling the dosage ratio of each component. A higher resin content can improve the strength and toughness of the composite material, while an appropriate amount of glass fiber can enhance the rigidity and wear resistance of the composite material. At the same time, an appropriate amount of diethylenetriamine as a curing agent can ensure the full curing of the resin and improve the stability and durability of the composite material.

[0025] The invention discloses a method for preparing a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material, comprising the following steps: preparing a fiber-reinforced composite material by using a bisphenol A-based hexafunctional resin and glass fiber in a ratio of 5:1. Diethylenetriamine (DETA) is used as a curing agent according to its ammonium hydroxide equivalent. The bisphenol A-based hexafunctional resin and DETA are uniformly mixed according to the required amount, and coated on 16 15cm glass fiber cloths by a hand lay-up process. The sheets are stacked on each other between two polytetrafluoroethylene sheets. All sheets are kept at a high temperature of 70-85°C between two plates of a molding press for 2-4 hours for curing, and finally a pressure of 50-60 psi is applied to press at 85-90°C for 2-10 minutes to flatten them. The prepared bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material is cooled at room temperature, taken out from the two plates of the molding press, and all dimensions of the composite sheet are measured after removing the polytetrafluoroethylene sheet. The bisphenol A-based hexafunctional resin and diethylenetriamine are cross-linked and doped with a glass fiber structure to obtain a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material with a high glass transition temperature and excellent heat resistance, which effectively improves the performance of epoxy resin models. The bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material (NCD) has a tensile strength of 64.8-68.4MPa, a flexural strength of 142.5-146.6MPa, an impact strength of 4.12-4.75J / cm, and a glass transition temperature of 159-162°C.

[0026] The present invention can control the curing degree of the resin and the performance of the composite material by adjusting the temperature and time of high-temperature curing. Appropriate curing temperature and time can ensure that the resin is fully cross-linked, and improve the heat resistance and mechanical properties of the composite material. By setting appropriate pressing parameters, the resin and glass fiber in the composite material can be ensured to be closely combined, the pores and defects can be reduced, and the density and mechanical properties of the composite material can be improved. By accurately controlling the dosage ratio of the raw materials and the concentration of the NaOH aqueous solution, the smooth progress of the resin synthesis can be ensured, and the performance of the resin can be optimized. This ratio can ensure that the resin has sufficient functional groups and reactivity, and provides a good basis for the preparation of subsequent composite materials. Appropriate heating and stirring temperature and time can promote the mixing and reaction of the raw materials, and ensure the uniformity and stability of the resin synthesis. Heating and stirring can further promote the synthetic reaction of the resin, and improve the cross-linking degree and performance of the resin. By distilling the resin, unreacted raw materials and by-products can be removed, and the purity of the resin can be improved. Higher distillation temperature and time can ensure sufficient distillation and purification of the resin. At the same time, the higher reaction yield shows that the preparation method has higher efficiency and feasibility.

[0027] The bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material prepared by the above-mentioned preparation method disclosed in the present invention is an epoxy resin composition with excellent chemical resistance and heat resistance, comprising bisphenol A-based hexafunctional resin, glass fiber and curing agent diethylenetriamine; the bisphenol A-based hexafunctional resin is generated by polymerization reaction of bisphenol A, formaldehyde and epichlorohydrin; through the cross-linking reaction of the bisphenol A-based hexafunctional resin and the curing agent diethylenetriamine having an amino group, the epoxy resin molecular chain is made tighter, the intermolecular force is enhanced, and it is also helpful to improve the curing speed and curing degree of the epoxy resin. Diethylenetriamine is used as a curing agent, and its amino group reacts with the epoxy group in the bisphenol A-based hexafunctional resin to form a stable cross-linked structure. Not only the curing efficiency of the epoxy resin is improved, but also the cured product has a higher hardness and glass transition temperature. The specific combination of the amino curing agent and the bisphenol A-based hexafunctional resin enables the two to give full play to their respective advantages during the curing process, thereby optimizing the performance of the epoxy resin, so that it has high hardness, high glass transition temperature and corrosion resistance. The addition of glass fiber significantly improves the mechanical properties of epoxy resin. The high strength and modulus of glass fiber make the composite material have higher hardness and toughness, suitable for various high load and impact environments.

[0028] The present invention discloses the application of the bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material prepared by the above-mentioned preparation method in the preparation of electronic component materials and insulating packaging materials; in terms of electronic component materials, the composite material provides a solid physical support for electronic components by virtue of its excellent mechanical properties, especially high tensile strength, flexural strength and impact toughness. Its high glass transition temperature ensures that the components can still maintain stable performance under high temperature environment, and is not prone to thermal aging or performance degradation, thereby significantly improving the reliability and service life of the components. In addition, the excellent electrical insulation performance of the composite material makes the components more stable in terms of electrical performance, and can effectively prevent the occurrence of safety problems such as current leakage or short circuit. These characteristics together provide a strong material guarantee for the miniaturization, lightweight and high performance of electronic components, and promote the continuous innovation and development of electronic component technology. In the field of insulating packaging materials, the application of the composite material also has significant advantages. Its good processing performance and formability make the packaging process more simple and efficient, and can accurately control the size and shape of the packaging structure. At the same time, the high insulation performance and heat resistance of the composite material enable the packaging structure to maintain stable electrical and mechanical properties in harsh environments such as high temperature and high humidity, and effectively resist interference and damage from the external environment. This not only improves the packaging quality and reliability of electronic components, but also provides a strong guarantee for the long-term stable operation of electronic products. More importantly, the preparation method of the composite material is highly controllable and repeatable, and can achieve large-scale industrial production to meet the large demand of the electronics industry for high-performance materials.

[0029] Example 1 A method for preparing a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material comprises the following steps: A 2L three-necked flask equipped with a mechanical stirrer and a condenser was placed in a constant temperature heating device. In the presence of an alkaline medium, 1.0 mol of bisphenol A and 4.0 mol of formaldehyde were added to the flask. Stir at 55°C for 2h, then 3 mol of epichlorohydrin was added to the reaction flask, and an aqueous solution of NaOH (2.2 mol, 40% concentration solution) was added dropwise. After the addition was completed, the temperature was raised to 80°C, the reaction mixture was stirred for 3h, and then 50mL of methyl ethyl ketone was added as a solvent to maintain the viscosity of the resin. Desalination was performed by vacuum distillation, and then the resin was distilled at 118°C for 3h to remove excess water, methyl ethyl ketone and epichlorohydrin, and cooled at room temperature to obtain a dark yellow, odorless bisphenol A-based hexafunctional resin with a yield of 82%.

[0030] The reaction was carried out with a molar ratio of 50:60:10 of bisphenol A-based hexafunctional resin: diethylenetriamine: glass fiber. Diethylenetriamine was used as a curing agent. The bisphenol A-based hexafunctional resin and diethylenetriamine were mixed evenly according to the required amount and coated on 16 15cm glass fiber cloths by hand lay-up process. They were stacked on each other between two polytetrafluoroethylene sheets. All sheets were kept at 80℃ between the two plates of the molding press for 2h high temperature curing, and finally pressed at 85℃ for 2min with a pressure of 50 psi. The prepared bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material was cooled at room temperature, taken out from the two plates of the molding press, and all dimensions of the composite sheet were measured after removing the polytetrafluoroethylene sheet. The bisphenol A-based hexafunctional resin was cross-linked with diethylenetriamine and doped with a glass fiber structure to obtain a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material with high glass transition temperature and excellent heat resistance, which effectively improved the performance of epoxy resin models. The bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material (NCD) has a tensile strength of 68.4 MPa, a flexural strength of 146.6 MPa, an impact strength of 4.75 J / cm, and a glass transition temperature of 162°C.

[0031] See also Figure 1 This is a schematic diagram of the preparation principle of the bisphenol A-based hexafunctional resin of the present invention; as can be seen from the figure, the theoretical molar ratio of the reaction is bisphenol A: formaldehyde: epichlorohydrin = 1:1:1.

[0032] See also Figure 2 FT-IR spectra of the bisphenol A based hexafunctional resin and industrial epoxy resin prepared in Example 1 of the present invention; in the FT-IR spectrum, 3410.12 cm -1 The peak at 2966.24cm is due to the expansion and contraction of the -OH group, but the transmittance of this peak is lower than that of commercially available epoxy resins, indicating that more -OH groups are used in the reaction. -1 The sharp peak at 1612.03 cm indicates CH stretching vibration. -1 The peak at 1515.05cm represents the stretching vibration of the aromatic ring C=C. -1 The peak at 1268.32 cm represents the stretching vibration of the aromatic ring C - C. -1 The COC stretching peak is observed at 846.23 cm -1 The characteristic strong peak of COC on the ethylene oxide ring was observed, confirming the occurrence of polymerization reaction.

[0033] Example 2 A method for preparing a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material comprises the following steps: A 2L three-necked flask equipped with a mechanical stirrer and a condenser was placed in a constant temperature heating device. In the presence of an alkaline medium, 1.2 mol of bisphenol A and 4.0 mol of formaldehyde were added to the flask. Stir at 60°C for 2 hours, then add 3. mol of epichlorohydrin to the reaction flask, and drop into an aqueous solution of NaOH (2.5 mol, 40% concentration solution). After the addition was completed, the temperature was raised to 80°C, the reaction mixture was stirred for 3.5 hours, and then 55 mL of methyl ethyl ketone was added as a solvent to maintain the viscosity of the resin. Desalination was performed by vacuum distillation, and then the resin was distilled at 118°C for 4 hours to remove excess water, methyl ethyl ketone and epichlorohydrin, and cooled at room temperature to obtain a dark yellow, odorless bisphenol A-based hexafunctional resin with a yield of 80%.

[0034] The invention discloses a method for preparing a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material, comprising the following steps: reacting a bisphenol A-based hexafunctional resin: diethylenetriamine: glass fiber at a molar ratio of 50:55:9. Diethylenetriamine is used as a curing agent, and the bisphenol A-based hexafunctional resin and diethylenetriamine are mixed evenly according to the required amount, and coated on 16 15cm glass fiber cloths by a hand lay-up process. Stacking each other between two polytetrafluoroethylene sheets. All sheets are kept at a high temperature of 80°C between two plates of a molding press for 2 hours for curing, and finally pressed at 85°C for 4 minutes under a pressure of 50psi to flatten them. The prepared bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material is cooled at room temperature, taken out from the two plates of the molding press, and all dimensions of the composite sheet are measured after the polytetrafluoroethylene sheet is removed. The bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material (NCD) has a tensile strength of 65.3 MPa, a flexural strength of 143.2 MPa, an impact strength of 4.38 J / cm, and a glass transition temperature of 162°C.

[0035] Example 3 A method for preparing a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material comprises the following steps: A 2L three-necked flask equipped with a mechanical stirrer and a condenser was placed in a constant temperature heating device. In the presence of an alkaline medium, 1.0 mol of bisphenol A and 4.0 mol of formaldehyde were added to the flask. Stir at 55°C for 2h, then 3 mol of epichlorohydrin was added to the reaction flask, and an aqueous solution of NaOH (2.2 mol, 40% concentration solution) was added dropwise. After the addition was completed, the temperature was raised to 80°C, the reaction mixture was stirred for 3h, and then 50mL of methyl ethyl ketone was added as a solvent to maintain the viscosity of the resin. Desalination was performed by vacuum distillation, and then the resin was distilled at 118°C for 3h to remove excess water, methyl ethyl ketone and epichlorohydrin, and cooled at room temperature to obtain a dark yellow, odorless bisphenol A-based hexafunctional resin with a yield of 78%.

[0036] The invention discloses a method for preparing a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material, comprising the following steps: reacting a bisphenol A-based hexafunctional resin: diethylenetriamine: glass fiber at a molar ratio of 45:53:8. Diethylenetriamine is used as a curing agent, and the bisphenol A-based hexafunctional resin and diethylenetriamine are mixed evenly according to the required amount, and coated on 12 15cm glass fiber cloths by a hand lay-up process. Stacking each other between two polytetrafluoroethylene sheets. All sheets are kept at a high temperature of 80°C between two plates of a molding press for 2 hours for curing, and finally pressed at 85°C for 2 minutes under a pressure of 50 psi. The prepared bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material is cooled at room temperature, taken out from the two plates of the molding press, and all dimensions of the composite sheet are measured after the polytetrafluoroethylene sheet is removed. The bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material (NCD) has a tensile strength of 64.8 MPa, a flexural strength of 142.5 MPa, an impact strength of 4.12 J / cm, and a glass transition temperature of 160°C.

[0037] Example 4 A method for preparing a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material comprises the following steps: A 2L three-necked flask equipped with a mechanical stirrer and a condenser was placed in a constant temperature heating device. In the presence of an alkaline medium, 1.0 mol of bisphenol A and 3.5 mol of formaldehyde were added to the flask. Stir at 70°C for 2h, then 4 mol of epichlorohydrin was added to the reaction flask, and an aqueous solution of NaOH (2.2 mol, 40% concentration solution) was dripped in. After the addition was completed, the temperature was raised to 70°C, the reaction mixture was stirred for 3h, and then 50 mL of methyl ethyl ketone was added as a solvent to maintain the viscosity of the resin. Desalting was performed by vacuum distillation, and then the resin was distilled at 118°C for 3h to remove excess water, methyl ethyl ketone and epichlorohydrin, and cooled at room temperature to obtain a dark yellow, odorless bisphenol A-based hexafunctional resin with a yield of 76%.

[0038] The invention discloses a method for preparing a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material, comprising the following steps: reacting a bisphenol A-based hexafunctional resin: diethylenetriamine: glass fiber at a molar ratio of 55:64:12. Diethylenetriamine is used as a curing agent, and the bisphenol A-based hexafunctional resin and diethylenetriamine are mixed evenly according to the required amount, and coated on 16 12cm glass fiber cloths by a hand lay-up process. Stacking each other between two polytetrafluoroethylene sheets. All sheets are kept at a high temperature of 70°C between two plates of a molding press for 2 hours for curing, and finally pressed at 85°C for 4 minutes under a pressure of 50psi to flatten them. The prepared bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material is cooled at room temperature, taken out from the two plates of the molding press, and all dimensions of the composite sheet are measured after the polytetrafluoroethylene sheet is removed. The bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material (NCD) has a tensile strength of 67.5 MPa, a flexural strength of 145.9 MPa, an impact strength of 4.26 J / cm, and a glass transition temperature of 159°C.

[0039] Example 5 A method for preparing a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material comprises the following steps: A 2L three-necked flask equipped with a mechanical stirrer and a condenser was placed in a constant temperature heating device. In the presence of an alkaline medium, 0.8 mol of bisphenol A and 5 mol of formaldehyde were added to the flask. Stir at 65°C for 3h, then add 3.5 mol of epichlorohydrin to the reaction flask, and drop into an aqueous solution of NaOH (2 mol, 40% concentration solution). After the addition was completed, the temperature was raised to 75°C, the reaction mixture was stirred for 3h, and then 80 mL of methyl ethyl ketone was added as a solvent to maintain the viscosity of the resin. Desalination was performed by vacuum distillation, and then the resin was distilled at 118°C for 3h to remove excess water, methyl ethyl ketone and epichlorohydrin, and cooled at room temperature to obtain a dark yellow, odorless bisphenol A-based hexafunctional resin with a yield of 78%.

[0040] The invention discloses a method for preparing a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material, comprising the following steps: reacting a bisphenol A-based hexafunctional resin: diethylenetriamine: glass fiber at a molar ratio of 55:55:10. Diethylenetriamine is used as a curing agent, and the bisphenol A-based hexafunctional resin and diethylenetriamine are mixed evenly according to the required amount, and coated on 16 12 cm glass fiber cloths by a hand lay-up process. Stacking each other between two polytetrafluoroethylene sheets. All sheets are kept at a high temperature of 75° C. between two plates of a molding press for 3 hours for curing, and finally a pressure of 55 psi is applied to press at 88° C. for 6 minutes to flatten it. The prepared bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material is cooled at room temperature, taken out from the two plates of the molding press, and after removing the polytetrafluoroethylene sheet, all dimensions of the composite sheet are measured.

[0041] Example 6 A method for preparing a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material comprises the following steps: A 2L three-necked flask equipped with a mechanical stirrer and a condenser was placed in a constant temperature heating device. In the presence of an alkaline medium, 1.1 mol of bisphenol A and 6.5 mol of formaldehyde were added to the flask. Stir at 70°C for 4 hours, then 5 mol of epichlorohydrin was added to the reaction flask, and an aqueous solution of NaOH (4 mol, 40% concentration solution) was dripped in. After the addition was completed, the temperature was raised to 90°C, the reaction mixture was stirred for 4 hours, and then 100 mL of methyl ethyl ketone was added as a solvent to maintain the viscosity of the resin. Desalination was performed by vacuum distillation, and then the resin was distilled at 118°C for 3.5 hours to remove excess water, methyl ethyl ketone and epichlorohydrin, and cooled at room temperature to obtain a dark yellow, odorless bisphenol A-based hexafunctional resin with a yield of 79%.

[0042] The invention discloses a method for preparing a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material, comprising the following steps: reacting a bisphenol A-based hexafunctional resin: diethylenetriamine: glass fiber at a molar ratio of 55:60:10. Diethylenetriamine is used as a curing agent, and the bisphenol A-based hexafunctional resin and diethylenetriamine are mixed evenly according to the required amount, and coated on 16 12cm glass fiber cloths by hand lay-up process. Stacking each other between two polytetrafluoroethylene sheets. All sheets are kept at a high temperature of 85°C between two plates of a molding press for 4 hours for curing, and finally a pressure of 60psi is applied to press at 90°C for 10 minutes to flatten it. The prepared bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material is cooled at room temperature, taken out from the two plates of the molding press, and all dimensions of the composite sheet are measured after the polytetrafluoroethylene sheet is removed.

[0043] Performance evaluation of bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite materials: 1. Tensile strength: Tensile strength measures the ability of a material to withstand forces that tend to pull it apart, and determines how far a material can stretch before breaking. The test was conducted on a UTM (Universal Testing Machine) Shimadzu AG 100, with a strain rate of 100% and a crosshead speed of 50 mm / min.

[0044] 2. Flexural strength: Flexural strength is the ability of a material to withstand a bending force applied perpendicular to its longitudinal axis. The stress caused by the bending load is a combination of compressive and tensile stresses. The bending properties are reported and calculated based on the maximum stress and strain occurring on the outer surface of the test bar. The test was performed on a UTM Shimadzu AG 100 with a crosshead speed of 1.2 mm / min.

[0045] 3. Impact strength: The results of the Izod impact test are expressed by the kinetic energy consumed by the pendulum to break the sample. The test specimens used in the test are notched specimens. The Izod impact strength is measured on the CEAST Izod tester.

[0046] 4. Glass transition temperature: The glass transition temperature measures the thermal stability of the material. The test was conducted on a differential scanning calorimeter (model DSC3500Sirius) from NETZSCH, Germany. The sample was heated from -20°C to 230°C in a nitrogen atmosphere, kept constant for 5 minutes to eliminate the thermal history, then cooled by -20°C, and heated to 200°C again. The gas flow rate was 50 mL / min, and the heating and cooling rates were both 10°C / min.

[0047] Table 1 Performance test results of the bisphenol A based hexafunctional resin / glass fiber / diethylenetriamine composite materials prepared in Examples 1-4 and the epoxy resin / glass fiber / diethylenetriamine composite materials prepared in the comparative example

[0048] Referring to Table 1, the performance test results of the bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite materials prepared in Examples 1-4 and the epoxy resin / glass fiber / diethylenetriamine prepared in the comparative example are shown. It can be seen from the table that the present invention combines the bisphenol A-based hexafunctional resin with diethylenetriamine, so that the product bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material has better mechanical properties and thermal stability than the epoxy resin used in industry. Compared with the traditional epoxy resin / glass fiber / diethylenetriamine (ECD), the tensile strength is 62.6 MPa, the tensile strength is 141.9 MPa, the impact strength is 3.89 J / cm, and the glass transition temperature is 158°C. The mechanical properties are significantly improved, which broadens the application range of the resin, has important practical application value, can meet engineering needs, and can achieve the purpose of the present invention.

[0049] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material, characterized in that: include: After heating and stirring bisphenol A and formaldehyde evenly, epichlorohydrin and NaOH aqueous solution are added, and after heating and stirring evenly, methyl ethyl ketone is added, and after desalting and distilling the resin, a bisphenol A-based hexafunctional resin is obtained. Then, the bisphenol A-based hexafunctional resin and diethylenetriamine are mixed evenly and coated on a number of glass fibers. After high-temperature curing, pressing and cooling, a bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material is obtained.

2. The method for preparing the bisphenol A based hexafunctional resin / glass fiber / diethylenetriamine composite material according to claim 1, characterized in that: The dosage ratio of bisphenol A: formaldehyde: epichlorohydrin: NaOH aqueous solution: methyl ethyl ketone is (0.8-1.2) mol: (4-6.5) mol: (3-5) mol: (2-4) mol: (50-100) mL; the mass fraction of the NaOH aqueous solution is 40%.

3. The method for preparing the bisphenol A based hexafunctional resin / glass fiber / diethylenetriamine composite material according to claim 1, characterized in that: The heating and stirring is performed at a temperature of 55-70° C. and for a time of 2-4 hours.

4. The method for preparing the bisphenol A based hexafunctional resin / glass fiber / diethylenetriamine composite material according to claim 1, characterized in that: The temperature of the heating and stirring is 70-90°C and the time is 3-4h.

5. The method for preparing the bisphenol A based hexafunctional resin / glass fiber / diethylenetriamine composite material according to claim 1, characterized in that: The temperature of the distilled resin is 118° C., and the time of the distilled resin is 3-4 hours. The reaction yield of the bisphenol A-based hexafunctional resin is 76%-82%.

6. The method for preparing the bisphenol A based hexafunctional resin / glass fiber / diethylenetriamine composite material according to claim 1, characterized in that: The molar ratio of the bisphenol A-based hexafunctional resin: diethylenetriamine: glass fiber is (45-55): (53-64): (8-12).

7. The method for preparing the bisphenol A based hexafunctional resin / glass fiber / diethylenetriamine composite material according to claim 1, characterized in that: The high temperature curing temperature is 70-85°C; the high temperature curing time is 2-4 hours.

8. The method for preparing the bisphenol A based hexafunctional resin / glass fiber / diethylenetriamine composite material according to claim 1, characterized in that: The pressing pressure is 50-60 psi; the pressing temperature is 85-90° C.; and the pressing time is 2-10 min.

9. A bisphenol A based hexafunctional resin / glass fiber / diethylenetriamine composite material, characterized in that: The bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material is prepared by the preparation method according to any one of claims 1 to 8, and has a tensile strength of 64.8-68.4 MPa, a flexural strength of 142.5-146.6 MPa, an impact strength of 4.12-4.75 J / cm, and a glass transition temperature of 159-162°C.

10. Use of the bisphenol A-based hexafunctional resin / glass fiber / diethylenetriamine composite material prepared by the preparation method according to any one of claims 1 to 8 in the preparation of electronic component materials and insulating packaging materials.

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