Epoxy resin composition having two-phase island-in-sea structure, composite material, and method for producing the same

Abstract

Provided are an epoxy resin composition having a two-phase island-in-sea structure, a composite material, and a method for producing the same. The epoxy resin composition having a two-phase island-in-sea structure comprises 50-120 parts by mass of a bisphenol-type glycidyl ether epoxy resin, 5-30 parts by mass of a low-viscosity aliphatic glycidyl ether epoxy resin, 50-120 parts by mass of an acid anhydride curing agent, 5-30 parts by mass of a polyether toughening agent, and 0-5 parts by mass of an accelerator. The epoxy resin composition and the epoxy resin composite material have a typical two-phase island-in-sea structure and have a clear toughening effect. The composite material produced has significantly improved impact toughness, improved flexural strength and flexural modulus, and after the epoxy resin is toughened by forming a two-phase island-in-sea structure, the toughening agent has a smaller effect on the tensile strength and tensile modulus of the material, and has almost no effect on the glass transition temperature.

Description

[Technical field]

[0001] This application claims priority to Chinese patent application No. 202210990323.4, filed on August 18, 2022, entitled "Epoxy resin composition with two-phase sea-island structure, composite material, and manufacturing method thereof," the entire contents of which are incorporated herein by reference.

[0002] The present application belongs to the technical field of epoxy resin composite materials, and specifically relates to an epoxy resin composition having a two-phase island-sea structure, a composite material, and a method for producing the same. [Background technology]

[0003] Epoxy resin is a resin base material for advanced composite materials and has excellent performance, especially in terms of wear resistance, mechanical properties, adhesive properties, chemical stability, electrical insulation, and adhesion to substrates, and can be seen in the fields of machinery, chemical industry, construction, rail transport, aerospace, etc. However, after epoxy resin is crosslinked and cured, a three-dimensional network structure is formed, the crosslink density is increased, the internal stress is improved, and the cured product is hard and brittle, has poor toughness and is prone to cleavage, limiting its application to high toughness composite materials, and therefore it is necessary to modify the epoxy resin to achieve the purpose of reinforcement and toughness.

[0004] At present, the common modification method is to add epoxy resin with flexible molecular chain, curing agent with flexible molecular chain or modifier with active terminal group to epoxy resin / acid anhydride system, disperse them at molecular level, and intercalate into the crosslinked network of epoxy resin by chemical bond, so as to make the whole epoxy crosslinked network flexible.For example, Chinese patent document with publication number CN108892776A discloses silicone modified epoxy resin and its preparation method, and by using polymethylphenylsiloxane modified bisphenol A type epoxy resin with Q-type POSS block, the good flexibility of polysiloxane can improve the toughness of modified epoxy resin, but such modification means can reduce the brittleness of epoxy resin to a certain extent, but inevitably sacrifice the rigidity and heat resistance of material.

[0005] Therefore, it is necessary to provide a modified epoxy resin material that, when used as a composite substrate material, has a significantly improved toughness and has little effect on the tensile strength, tensile modulus, and heat resistance of the material. Summary of the Invention

[0006] The problem to be solved by the present invention is to provide an epoxy resin composition having a two-phase island-in-sea structure, a composite material, and a manufacturing method thereof. The epoxy resin composition and the epoxy resin composite material have a typical two-phase island-in-sea structure, and have obvious toughening effects, and the composite material produced has significantly improved impact toughness, flexural strength and flexural modulus, and after the epoxy resin is toughened by forming a two-phase island-in-sea structure, the toughener has a smaller effect on the tensile strength and tensile modulus of the material, and has almost no effect on the glass transition temperature.

[0007] In order to solve the above problems, one aspect of the present application provides an epoxy resin composition having a two-phase island-in-sea structure, which includes, by mass, 50-120 parts of a bisphenol-type glycidyl ether epoxy resin, 5-30 parts of a low-viscosity aliphatic glycidyl ether epoxy resin, 50-120 parts of an acid anhydride curing agent, 5-30 parts of a polyether toughening agent, and 0-5 parts of an accelerator.

[0008] Preferably, the epoxy resin composition having a two-phase island-in-sea structure contains, by mass, 80 to 90 parts of a bisphenol-type glycidyl ether epoxy resin, 10 to 20 parts of a low-viscosity aliphatic glycidyl ether epoxy resin, 80 to 90 parts of an acid anhydride curing agent, 10 to 20 parts of a polyether toughening agent, and 0 to 2 parts of an accelerator.

[0009] Preferably, the polyether toughening agent is one or more of polyoxypropylene glycol having a molecular weight of 200-4000 and polytetramethylene ether glycol having a molecular weight of 200-4000.

[0010] Preferably, the bisphenol glycidyl ether epoxy resin is one or a combination of a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, and a bisphenol S type epoxy resin.

[0011] Preferably, the low viscosity aliphatic glycidyl ether epoxy resin is one or a combination of more of n-butyl glycidyl ether, C12-C14 polyalkyl glycidyl ether, polyethylene glycol diglycidyl ether, ethylene glycol diglycidyl ether, 1,2-propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, diglycidyl ether, neopentyl glycol diglycidyl ether.

[0012] Preferably, the acid anhydride curing agent is one or a combination of more of tetrahydrophthalic anhydride, hexahydrophthalic anhydride, tetrahydromethylphthalic anhydride, hexahydromethylphthalic anhydride, trimellitic anhydride, tung oil anhydride, methylnadic anhydride, and maleic anhydride.

[0013] Another aspect of the present application provides a method for preparing the above epoxy resin composition having a two-phase islands-in-the-sea structure, which comprises the following steps: The bisphenol-type glycidyl ether epoxy resin, the low-viscosity aliphatic glycidyl ether epoxy resin, the acid anhydride curing agent, the polyether toughening agent, and the accelerator are mixed and stirred to obtain the epoxy resin composition having the two-phase sea-island structure.

[0014] Preferably, specifically, the method includes the following steps: In S1, the bisphenol-type glycidyl ether epoxy resin and the low-viscosity aliphatic glycidyl ether epoxy resin are mixed and subjected to a first ultrasonic emulsification to obtain a modified epoxy resin component. In S2, the acid anhydride curing agent, the polyether toughening agent and the accelerator are mixed and subjected to a second ultrasonic emulsification to obtain a modified curing agent component. In S3, the modified epoxy resin component and the modified curing agent component are mixed to obtain the epoxy resin composition having the two-phase island-sea structure.

[0015] Preferably, the first ultrasonic emulsification and / or the second ultrasonic emulsification has an ultrasonic frequency of 25 to 60 KHz and an ultrasonic output of 600 to 6000 W.

[0016] Another aspect of the present application provides an epoxy resin composite material obtained by combining a resin substrate material with a fiber-reinforced material, wherein the resin substrate material is the above-mentioned epoxy resin composition having a two-phase island-in-sea structure, or an epoxy resin composition having a two-phase island-in-sea structure produced by the above-mentioned production method.

[0017] Preferably, in the epoxy resin composite material, the mass fraction of the fiber reinforcement material is 20 to 40%.

[0018] Another aspect of the present application provides a method for producing the above epoxy resin-based composite material, which includes the following steps: In A1, an epoxy resin composition having the two-phase island-sea structure is produced. In A2, the epoxy resin composition having a two-phase island-in-sea structure is used to immerse a fiber-reinforced material, and the epoxy resin composite material is produced by a stretch molding process.

[0019] Compared with the prior art, the present application has the following beneficial effects:

[0020] The epoxy resin composition and epoxy resin composite material of the present application have a typical two-phase island-in-sea structure, and have obvious toughening effects. The epoxy resin composite material has significantly improved impact toughness, flexural strength and flexural modulus, and after forming a two-phase island-in-sea structure to toughen the epoxy resin, the toughener has little effect on the tensile strength and tensile modulus of the material, and has almost no effect on the glass transition temperature.

[0021] The method for producing an epoxy resin composition of the present invention is to mix a bisphenol-type glycidyl ether epoxy resin with a low-viscosity aliphatic glycidyl ether epoxy resin, and then perform ultrasonic emulsification, and the "cavitation" effect of ultrasonic emulsification can reduce the viscosity of the bisphenol-type glycidyl ether epoxy resin, improve the workability of the epoxy resin, and improve the fiber immersion effect during the production process, so that the epoxy resin composition is used in the production process of epoxy resin-based composite material products, and the internal fibers have a fast immersion speed and high immersion effect in the adhesive liquid. In addition, the acid anhydride curing agent, the polyether toughening agent, and the accelerator are mixed and then ultrasonically emulsified, and the "cavitation" effect of ultrasonic emulsification can uniformly disperse the toughening agent in the curing agent at a nanoscale level, providing the microenvironmental conditions necessary for the epoxy resin curing reaction and the formation of a uniformly distributed two-phase sea-island structure, thereby exerting a remarkable toughening effect. [Brief description of the drawings]

[0022] The drawings herein are incorporated into the specification and constitute a part of this specification, illustrate embodiments that are applicable to the present application, and are used together with the specification to interpret the principles of the present application. In order to more clearly explain the technical solutions of the embodiments of the present application, the drawings that need to be used in the description of the embodiments are briefly introduced below, and obviously, those skilled in the art can obtain other drawings based on these drawings without any creative efforts. [Figure 1] FIG. 2 is a scanning electron microscope image of the epoxy resin composite material of Example 1 of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The technical solution of the present invention will be described clearly and completely below with reference to the embodiments of the present invention, and of course, the described embodiments are only some of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments that a person skilled in the art can obtain without creative labor also belong to the protection scope of the present invention.

[0024] A first aspect of the present invention provides an epoxy resin composition having a two-phase islands-in-a-sea structure, which includes, by weight, 50-120 parts of a bisphenol-type glycidyl ether epoxy resin, 5-30 parts of a low-viscosity aliphatic glycidyl ether epoxy resin, 50-120 parts of an acid anhydride curing agent, 5-30 parts of a polyether toughening agent, and 0-5 parts of an accelerator.

[0025] In the epoxy resin composition having a two-phase island-in-the-sea structure of the present application, by adding a polyether toughening agent, spherical particles consisting of agglomerations of the polyether toughening agent become a dispersed phase in a continuous phase consisting of an epoxy resin crosslinked network, and the particles of the dispersed phase usually have a diameter of several μm or less, changing the epoxy resin cured material from a homogeneous system to a single multiphase system, i.e., an "island-in-the-sea structure" is formed. When the "island-in-the-sea structure" is formed, the cleavage resistance of the material is mutated and the fracture toughness of the material is greatly improved (several times, even tens of times), with little loss in the mechanical properties and heat resistance inherent to the material, an effect that cannot be compared with the flexibility modification of epoxy resin.

[0026] In some embodiments, the epoxy resin composition having a two-phase islands-in-the-sea structure includes, by weight, 80-90 parts of a bisphenol-type glycidyl ether epoxy resin, 10-20 parts of a low-viscosity aliphatic glycidyl ether epoxy resin, 80-90 parts of an acid anhydride curing agent, 10-20 parts of a polyether toughening agent, and 0-2 parts of an accelerator.

[0027] In some embodiments, the polyether toughening agent is one or more of polyoxypropylene glycols having a molecular weight of 200-4000 and polytetramethylene ether glycols having a molecular weight of 200-4000.

[0028] The specific type of polyether toughening agent selected in the embodiment of the present application is a polypropylene oxide compound in which polyoxypropylene glycol is end-blocked with alcoholic hydroxyl groups, its molecular structure is a polymer with a long-chain linear molecular structure, both ends are blocked with hydroxyl groups, the presence of ether bonds in the molecular chain greatly increases the flexibility of the molecular chain in the network structure, the polypropylene oxide segment is incompatible with the epoxy cured network structure, the polyether polyol precipitates during the curing process to form a dispersed phase structure, the epoxy resin is cured to form a continuous phase structure, and finally forms a two-phase "sea island structure", when the resin composition is used in a composite material and the composite material is subjected to the action of force, the dispersed phase generates stress concentrators, which induces a large number of silver strands and shear bands, which controls the growth of silver strands, stops the generation of silver strands, and induces shear deformation. Therefore, the "sea island structure" can prevent the progression of cracks and effectively exert the effect of toughening. Polytetramethylene ether glycol is considered to be a polyether toughening agent, and its toughening mechanism is similar to that of polyoxypropylene glycol.

[0029] In some embodiments, the bisphenol glycidyl ether epoxy resin may be one or more of a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, and a bisphenol S type epoxy resin.

[0030] In some embodiments, the low viscosity aliphatic glycidyl ether epoxy resin may be one or a combination of more of n-butyl glycidyl ether, C12-C14 polyalkyl glycidyl ether, polyethylene glycol diglycidyl ether, ethylene glycol diglycidyl ether, 1,2-propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, diglycidyl ether, neopentyl glycol diglycidyl ether.

[0031] The specific type of low-viscosity aliphatic glycidyl ether epoxy resin selected in the examples of the present application is a long-chain linear polymer, has excellent flexibility, can improve the toughness of the cured product, has a low relative molecular weight, a small viscosity, and good processability, and can be used as an active diluent to improve the pot life of the adhesive liquid.

[0032] In some examples, the anhydride curing agent may be one or a combination of more of tetrahydrophthalic anhydride, hexahydrophthalic anhydride, tetrahydromethylphthalic anhydride, hexahydromethylphthalic anhydride, trimellitic anhydride, tung oil anhydride, methylnadic anhydride, and maleic anhydride.

[0033] The specific types of acid anhydride curing agents selected in the examples of the present application provide excellent performance of epoxy resin cured products cured with acid anhydrides, excellent heat resistance and chemical stability, and are less volatile, less toxic, less irritating to the skin, more compatible with epoxy resins, have a smaller viscosity, can be modified by adding fillers, are advantageous in reducing costs, have a longer service life, and are easy to apply.

[0034] In some embodiments, the accelerator is a nucleophilic accelerator. Further, the nucleophilic accelerator may be triethylamine, benzyldimethylamine (BDMA), dimethylaminomethylphenol (DMP-10), tris(dimethylaminomethyl)phenol (DMP-30), 2-ethylhexanoate, 2-methylimidazole, 2-ethyl-4-methylimidazole, N,N-dimethylaniline, triethanolamine, naphthenate, octylate, and the like.

[0035] The specific type of nucleophilic accelerator used in the examples of this application has a dual catalytic action on the acid anhydride curing agent, that is, it has a catalytic action on not only the acid anhydride but also the epoxy resin. The catalytic action of the nucleophilic accelerator in the epoxy / acid anhydride curing system is to first generate oxygen anions and react with the acid anhydride to generate new carboxyl anions, which then react with the epoxy group to generate new alkoxy anions. Such reactions proceed alternately to form a polyester-type crosslinked structure, and can also initiate the catalytic polymerization reaction of the epoxy group to obtain a polyether crosslinked network structure. Most nucleophilic accelerators belong to Lewis bases, and the stronger the Lewis basicity, the smaller the steric hindrance of the substituents and the greater the catalytic activity, and the structure and performance of the accelerator greatly affect the crosslinking curing reaction rate and the performance of the cured product. The accelerator selected in this invention, such as DMP-30, is stable at room temperature, greatly extending the use period of the adhesive liquid, and when heated to about 100°C, it quickly decomposes to generate tertiary amines, generating a catalytic effect.

[0036] In some embodiments, the epoxy resin composition having a two-phase islands-in-the-sea structure further comprises 1 to 3 parts of a mold release agent.

[0037] In some examples, the release agent may be a metal stearate, such as barium stearate, calcium stearate, magnesium stearate, cadmium stearate, zinc stearate, lead stearate, and the like.

[0038] A second aspect of the present embodiment provides a method for preparing the above epoxy resin composition having a two-phase islands-in-the-sea structure, which includes the following steps: A bisphenol-type glycidyl ether epoxy resin, a low-viscosity aliphatic glycidyl ether epoxy resin, an acid anhydride curing agent, a polyether toughening agent, and an accelerator are mixed and stirred to obtain an epoxy resin composition having a two-phase sea-island structure.

[0039] In some embodiments, the method for preparing an epoxy resin composition having a two-phase islands-in-the-sea structure may further include the following steps. In S1, a bisphenol-type glycidyl ether epoxy resin and a low-viscosity aliphatic glycidyl ether epoxy resin are mixed and subjected to a first ultrasonic emulsification to obtain a modified epoxy resin component. In S2, the acid anhydride curing agent, the polyether toughening agent and the accelerator are mixed and subjected to a second ultrasonic emulsification to obtain a modified curing agent component. In S3, the modified epoxy resin component and the modified curing agent component are mixed to obtain an epoxy resin composition having a two-phase island-sea structure.

[0040] In the examples of the present application, the bisphenol-type glycidyl ether epoxy resin is mixed with the low-viscosity aliphatic glycidyl ether epoxy resin, and then ultrasonic emulsification is carried out. The "cavitation" effect of the ultrasonic emulsification modifies the bisphenol-type glycidyl ether epoxy resin. The viscosity of the modified bisphenol-type glycidyl ether epoxy resin is reduced, which improves the workability of the epoxy resin and improves the fiber immersion effect during the production process. Therefore, the epoxy resin composition is used in the production process of epoxy resin composite products, and the inner fibers are immersed in the adhesive liquid at a fast speed and have a high immersion effect.

[0041] In the examples of the present application, an acid anhydride curing agent, a polyether toughening agent and an accelerator are mixed together and then ultrasonically emulsified. The "cavitation" effect of the ultrasonic emulsification modifies the curing agent, and the modified toughening agent is uniformly dispersed in the curing agent at the nanoscale level, providing the microenvironmental conditions necessary for the epoxy resin curing reaction and the formation of a uniformly distributed two-phase sea-island structure, thereby exerting a remarkable toughening effect.

[0042] In some embodiments, the first ultrasonic emulsification and / or the second ultrasonic emulsification is performed in a high power ultrasonic emulsifier.

[0043] In some embodiments, the first ultrasonic emulsification and / or the second ultrasonic emulsification has an ultrasonic frequency of 25-60 KHz and an ultrasonic power of 600-6000 W.

[0044] In some embodiments, the first ultrasonic emulsification and / or the second ultrasonic emulsification is performed at room temperature.

[0045] In some embodiments, a release agent may be added and mixed in step S2 to facilitate smooth release of the product from the mold.

[0046] A third aspect of the present invention provides an epoxy resin substrate composite material obtained by combining a resin substrate material with a fiber-reinforced material, the resin substrate material being the above-mentioned epoxy resin composition having a two-phase island-in-sea structure or an epoxy resin composition having a two-phase island-in-sea structure produced by the above-mentioned production method.

[0047] In the examples of the present application, the above-mentioned epoxy resin composition having a two-phase island-in-sea structure is used as the resin base material, which has a typical two-phase island-in-sea structure and has obvious toughening effect. The composite material produced has greatly improved impact toughness, improved flexural strength and flexural modulus. After forming a two-phase island-in-sea structure to toughen the epoxy resin, the effect of the toughener on the tensile strength and tensile modulus of the material is even smaller, and has almost no effect on the glass transition temperature.

[0048] In some embodiments, in the epoxy resin-based composite material, the mass fraction of the fiber reinforcement material may be 20-40%, which can further ensure the toughness, rigidity and heat resistance of the composite material.

[0049] A fourth aspect of the present embodiment provides a method for producing the above epoxy resin-based composite material, which includes the following steps: In A1, an epoxy resin composition having a two-phase island-in-sea structure is produced. In A2, a fiber-reinforced material is immersed in an epoxy resin composition having a two-phase island-in-sea structure, and an epoxy resin composite material is produced by a stretch molding process.

[0050] In some embodiments, step A2 may further include the following steps: In A21, the fiber reinforcement material is arranged according to the threading diagram. In A22, a fiber reinforced material is immersed in an epoxy resin composition having a two-phase islands-in-the-sea structure. In A23, the fiber-reinforced material after soaking is sequentially preformed, extruded and cured, pulled, cut, and finished to obtain an epoxy resin composite material.

[0051] (Example) The following examples will more specifically describe the contents of the present disclosure, but these examples are merely illustrative, and various modifications and changes within the scope of the present disclosure will be obvious to those skilled in the art. All parts, percentages, and ratios reported in the following examples are by weight unless otherwise specified, and all reagents used in the examples may be purchased commercially or obtained by synthesis according to conventional methods, and may be used as is without further treatment, and the equipment used in the examples is purchased commercially.

[0052] Example 1 The method for producing an epoxy resin composite material according to this embodiment includes the following steps.

[0053] <1. Production of epoxy resin composition having two-phase island-sea structure> In 101, 85 parts of bisphenol F type epoxy resin and 15 parts of 1,4-butanediol diglycidyl ether are mixed and ultrasonically emulsified at room temperature using a high-power ultrasonic emulsifier, with an ultrasonic frequency of 40 KHz and an ultrasonic output of 2000 W, to obtain a modified epoxy resin component.

[0054] In 102, 60 parts of tetrahydromethylphthalic anhydride, 20 parts of maleic anhydride, 10 parts of polyoxypropylene glycol with a molecular weight of 2000, 1 part of tris(dimethylaminomethyl)phenol (DMP-30) accelerator, and 2 parts of magnesium stearate as a release agent are mixed and ultrasonically emulsified at room temperature using a high-power ultrasonic emulsifier, with an ultrasonic frequency of 45KHz and an ultrasonic output of 2500W, to obtain a modified hardener component.

[0055] In 103, the modified epoxy resin component and the modified hardener component are mixed and mechanically stirred to obtain an epoxy resin composition having a uniformly dispersed two-phase island-in-sea structure.

[0056] <2. Manufacturing of epoxy resin composite materials> In 201, glass fiber and glass fiber sewing felt are used as fiber reinforcement materials, the total amount of glass fiber and sewing felt accounts for 22% of the total mass of the composite material, and the fiber reinforcement materials are arranged according to the threading diagram.

[0057] At 202, a fiber reinforced material is impregnated with an epoxy resin composition having a two-phase islands-in-the-sea structure.

[0058] In step 203, the soaked fiber-reinforced material is sequentially preformed, extruded and cured, pulled, cut, and finished to obtain an epoxy resin composite material.

[0059] The microstructure of the obtained epoxy resin composite material was observed using a scanning electron microscope. As shown in Figure 1, it was found that a clear two-phase island-sea structure was formed in the epoxy resin composite material (area indicated by a block).

[0060] Example 2 The method for producing an epoxy resin composite material according to this embodiment includes the following steps.

[0061] <1. Production of epoxy resin composition having two-phase island-sea structure> In 101, 80 parts of bisphenol A type epoxy resin and 20 parts of C12-C14 polyalkyl glycidyl ether are mixed, and ultrasonic emulsified at room temperature using a high-power ultrasonic emulsifier, with an ultrasonic frequency of 35KHz and an ultrasonic output of 3000W, to obtain a modified epoxy resin component.

[0062] In 102, 55 parts of hexahydromethylphthalic anhydride, 25 parts of tetrahydromethylphthalic anhydride, 20 parts of polyoxypropylene glycol having a molecular weight of 800, 1 part of triethylamine as an accelerator, and 2 parts of zinc stearate as a release agent are mixed, and ultrasonically emulsified at room temperature using a high-power ultrasonic emulsifier, with an ultrasonic frequency of 35KHz and an ultrasonic output of 3000W, to obtain a modified hardener component.

[0063] In 103, the modified epoxy resin component and the modified hardener component are mixed and mechanically stirred to obtain an epoxy resin composition having a uniformly dispersed two-phase island-in-sea structure.

[0064] <2. Manufacturing of epoxy resin composite materials> In 201, glass fiber and glass fiber sewing felt are used as fiber reinforcement materials, the total amount of glass fiber and sewing felt accounts for 24% of the total mass of the composite material, and the fiber reinforcement materials are arranged according to the threading diagram.

[0065] At 202, a fiber reinforced material is immersed in an epoxy resin composition having a two-phase islands-in-the-sea structure.

[0066] In step 203, the soaked fiber-reinforced material is sequentially preformed, extruded and cured, pulled, cut, and finished to obtain an epoxy resin composite material.

[0067] Example 3 The method for producing an epoxy resin composite material according to this embodiment includes the following steps.

[0068] <1. Production of epoxy resin composition having two-phase island-sea structure> In 101, 90 parts of bisphenol A type epoxy resin and 10 parts of 1,2-propylene glycol diglycidyl ether are mixed, and ultrasonic emulsified at room temperature using a high-power ultrasonic emulsifier, with an ultrasonic frequency of 50KHz and an ultrasonic output of 3500W, to obtain a modified epoxy resin component.

[0069] In 102, 35 parts of tetrahydromethylphthalic anhydride, 45 parts of trimellitic anhydride, 15 parts of polytetramethylene ether glycol having a molecular weight of 2000, 1 part of 2-methylimidazole, and 2 parts of lead stearate as a release agent are mixed and ultrasonically emulsified at room temperature using a high-power ultrasonic emulsifier, with an ultrasonic frequency of 35KHz and an ultrasonic output of 3000W, to obtain a modified hardener component.

[0070] In 103, the modified epoxy resin component and the modified hardener component are mixed and mechanically stirred to obtain an epoxy resin composition having a uniformly dispersed two-phase island-in-sea structure.

[0071] <2. Manufacturing of epoxy resin composite materials> In 201, glass fiber and glass fiber sewing felt are used as fiber reinforcement materials, the total amount of glass fiber and sewing felt accounts for 21% of the total mass of the composite material, and the fiber reinforcement materials are arranged according to the threading diagram.

[0072] At 202, a fiber reinforced material is immersed in an epoxy resin composition having a two-phase islands-in-the-sea structure.

[0073] In step 203, the soaked fiber-reinforced material is sequentially preformed, extruded and cured, pulled, cut, and finished to obtain an epoxy resin composite material.

[0074] Example 4 The method for producing an epoxy resin composite material according to this embodiment includes the following steps.

[0075] <1. Production of epoxy resin composition having two-phase island-sea structure> In 101, 90 parts of bisphenol A type epoxy resin and 10 parts of ethylene glycol diglycidyl ether are mixed, and ultrasonic emulsified at room temperature using a high-power ultrasonic emulsifier, with an ultrasonic frequency of 55 KHz and an ultrasonic output of 4000 W, to obtain a modified epoxy resin component.

[0076] In 102, 80 parts of tetrahydromethylphthalic anhydride, 10 parts of methylnadic anhydride, 20 parts of polytetramethylene ether glycol with a molecular weight of 3000, 1 part of 2-ethyl-4-methylimidazole as an accelerator, and 2 parts of zinc stearate as a release agent are mixed and ultrasonically emulsified at room temperature using a high-power ultrasonic emulsifier, with an ultrasonic frequency of 30KHz and an ultrasonic output of 4500W, to obtain a modified hardener component.

[0077] In 103, the modified epoxy resin component and the modified hardener component are mixed and mechanically stirred to obtain an epoxy resin composition having a uniformly dispersed two-phase island-in-sea structure.

[0078] <2. Manufacturing of epoxy resin composite materials> In 201, the fiber reinforcement materials are glass fiber and glass fiber sewing felt, the total amount of the glass fiber and sewing felt accounts for 23.5% of the total mass of the composite material, and the fiber reinforcement materials are arranged according to the threading diagram.

[0079] At 202, a fiber reinforced material is immersed in an epoxy resin composition having a two-phase islands-in-the-sea structure.

[0080] In step 203, the soaked fiber-reinforced material is sequentially preformed, extruded and cured, pulled, cut, and finished to obtain an epoxy resin composite material.

[0081] Comparative Example 1 In the manufacturing method of the epoxy resin composite material of this comparative example, the manufacturing steps of the epoxy resin composite material are the same as those in Example 1, and the difference is that the manufacturing method of the epoxy resin composition includes the following steps.

[0082] In 101, 90 parts of bisphenol A type epoxy resin and 10 parts of ethylene glycol diglycidyl ether are mixed and stirred uniformly to obtain an epoxy resin component.

[0083] In 102, 80 parts of tetrahydromethylphthalic anhydride, 10 parts of methylnadic anhydride, 1 part of 2-ethyl-4-methylimidazole as an accelerator, and 2 parts of zinc stearate as a release agent are mixed and stirred uniformly to obtain a hardener component.

[0084] In 103, the epoxy resin component and the hardener component are mixed and after mechanical stirring, an epoxy resin composition is obtained.

[0085] Comparative Example 2 In the method for producing an epoxy resin composite material of this comparative example, the types and parts by mass of each production raw material were the same as those in Example 1, with the difference being that ultrasonic emulsification was not performed in step 101.

[0086] The epoxy resin composition prepared in this comparative example has a short pot life, and the composite material prepared using this composition has a certain color difference on the surface, and has obvious poor demolding phenomenon after a certain period of time after production, and at the same time, the mechanical properties are reduced to a certain extent.

[0087] Comparative Example 3 In the manufacturing method of the epoxy resin composite material of this comparative example, the types and mass parts of each manufacturing raw material are all the same as those in Example 1, with the difference being that ultrasonic emulsification is not performed in step 102.

[0088] The epoxy resin composition prepared in this comparative example has a significantly short pot life, and the composite material prepared using this composition has a low surface gloss, and after a certain period of time after production, there is white powder on the surface of the product, which appears intermittently, and the Tg value of the product is significantly reduced. It is analyzed that the hardener components are not mixed uniformly enough and do not reach sufficient contact at the molecular level. Testing the static mechanical properties and glass transition temperature of epoxy resin composites

[0089] The glass transition temperature and static mechanical properties of the epoxy resin composite materials obtained in the above Examples and Comparative Examples were tested. The test methods were as follows, and the test results are shown in Table 1.

[0090] DMA test: Test the samples using a DMA1 tester from METTLER TOLEDO Instruments, Switzerland. Test parameters: heating rate 20℃ / min, temperature range 30℃~150℃.

[0091] The test procedures for the mechanical properties of epoxy resin composite materials, such as tensile properties, bending properties and impact properties, refer to Chinese national standards GB / T 1447-2005, GB / T 1449-2005 and GB / T 1451-2005 respectively.

[0092] [Table 1]

[0093] Of course, the above examples are merely illustrative and do not limit the embodiments. Those skilled in the art can make other different types of modifications or variations in addition to the above description. It is not possible to cover all embodiments here. Any obvious changes or variations caused thereby still fall within the scope of protection of the present invention.

Claims

1. 50 to 120 parts by mass of a bisphenol-type glycidyl ether epoxy resin; 5 to 30 parts by mass of a low-viscosity aliphatic glycidyl ether epoxy resin; 50 to 120 parts by mass of an acid anhydride hardener; 5 to 30 parts by weight of a polyether toughening agent; 0 to 5 parts by weight of an accelerator; 1. An epoxy resin composition having a two-phase island-in-the-sea structure comprising:

2. 80 to 90 parts by mass of a bisphenol-type glycidyl ether epoxy resin; 10 to 20 parts by mass of a low viscosity aliphatic glycidyl ether epoxy resin; 80 to 90 parts by mass of an acid anhydride hardener; 10 to 20 parts by weight of a polyether toughening agent; 0 to 2 parts by weight of an accelerator; 2. The epoxy resin composition having a two-phase islands-in-the-sea structure according to claim 1 ,

3. The polyether toughening agent is one or more of polyoxypropylene glycol having a molecular weight of 200 to 4000 and polytetramethylene ether glycol having a molecular weight of 200 to 4000; The epoxy resin composition having a two-phase island-in-sea structure according to claim 1.

4. The bisphenol glycidyl ether epoxy resin is one or a combination of a bisphenol A epoxy resin, a bisphenol F epoxy resin, and a bisphenol S epoxy resin, The low-viscosity aliphatic glycidyl ether epoxy resin is one or a combination of a plurality of n-butyl glycidyl ether, C12-C14 polyalkyl glycidyl ether, polyethylene glycol diglycidyl ether, ethylene glycol diglycidyl ether, 1,2-propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, diglycidyl ether, and neopentyl glycol diglycidyl ether; The acid anhydride curing agent is one or a combination of two or more of tetrahydrophthalic anhydride, hexahydrophthalic anhydride, tetrahydromethylphthalic anhydride, hexahydromethylphthalic anhydride, trimellitic anhydride, tung oil anhydride, methylnadic anhydride, and maleic anhydride. The epoxy resin composition having a two-phase island-in-sea structure according to claim 1.

5. A method for producing an epoxy resin composition having a two-phase island-sea structure according to any one of claims 1 to 4, comprising the steps of: a step of mixing and stirring the bisphenol-type glycidyl ether epoxy resin, the low-viscosity aliphatic glycidyl ether epoxy resin, the acid anhydride curing agent, the polyether toughening agent, and the accelerator to obtain the epoxy resin composition having the two-phase sea-island structure; A manufacturing method comprising:

6. in particular, A step S1 of mixing the bisphenol-type glycidyl ether epoxy resin and the low-viscosity aliphatic glycidyl ether epoxy resin and performing a first ultrasonic emulsification to obtain a modified epoxy resin component; A step S2 of mixing the acid anhydride curing agent, the polyether toughening agent, and the accelerator, and performing a second ultrasonic emulsification to obtain a modified curing agent component; A step S3 of mixing the modified epoxy resin component and the modified curing agent component to obtain the epoxy resin composition having the two-phase sea-island structure; The method of claim 5, comprising:

7. The first ultrasonic emulsification and / or the second ultrasonic emulsification has an ultrasonic frequency of 25 to 60 KHz and an ultrasonic output of 600 to 6000 W. The method according to claim 6.

8. An epoxy resin composite material obtained by compounding a resin substrate material and a fiber reinforced material, The resin substrate material is an epoxy resin composition having a two-phase island-sea structure according to any one of claims 1 to 4, or an epoxy resin composition having a two-phase island-sea structure produced by the production method according to any one of claims 5 to 7. Epoxy resin-based composite material.

9. In the epoxy resin-based composite material, the mass fraction of the fiber reinforcement material is 20 to 40%. The epoxy resin composite material according to claim 8.

10. A method for producing the epoxy resin composite material according to claim 8 or 9, comprising the steps of: A step A1 of producing an epoxy resin composition having a two-phase island-sea structure; A step A2 of immersing a fiber-reinforced material in the epoxy resin composition having a two-phase island-in-sea structure and producing the epoxy resin-based composite material by a stretch molding process; A manufacturing method comprising:

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