High-strength toughened epoxy vinyl ester resin composition and preparation method thereof

Abstract

The invention provides a high-strength toughened epoxy vinyl ester resin composition, which is prepared by introducing a functional olefin monomer containing tert-butyl hindered amine into epoxy vinyl ester to obtain modified epoxy vinyl ester resin, and reacting the modified epoxy vinyl ester resin with isocyanate. A dynamic hindered urea covalent bond generated by the reaction enables a hindered urea group to have reversible dynamic property at room temperature, so that the rigidity of a casting body is superior to that of common vinyl resin; and when the material is subjected to external force, the dynamic hindered urea bond can be broken preferentially because the bond energy is lower than that of a covalent bond, so that energy is absorbed, stress is dissipated, and the toughness of the vinyl resin is improved. The high-strength toughened epoxy vinyl ester resin composition disclosed by the invention can be rapidly cured at room temperature, is excellent in comprehensive performance, and has improved rigidity and toughness at the same time.

Description

Technical Field

[0001] The invention relates to the technical field of vinyl ester resins, and in particular to a high-strength toughened epoxy vinyl ester resin composition and a preparation method thereof. Background Art

[0002] Epoxy vinyl ester resin, referred to as vinyl resin, is a type of unsaturated resin obtained by the ring-opening addition reaction of epoxy resin and acrylic acid or methacrylic acid, and then dissolved in cross-linking monomers such as styrene for dilution. The introduction of vinyl makes epoxy vinyl ester resin inherit the excellent mechanical properties of traditional epoxy resin while having the excellent processability and chemical corrosion resistance of unsaturated polyester. Although epoxy vinyl ester resin has excellent comprehensive performance and is widely used in industrial anti-corrosion, construction engineering and other fields. However, ordinary vinyl resin still has the common problems of traditional thermosetting resins, namely, high brittleness, poor impact resistance and low elongation at break.

[0003] Patent 202110374586.8 discloses a method for preparing a high-strength and high-toughness vinyl ester resin, first reacting a diisocyanate with a polyether diol to prepare an isocyanate-terminated polyurethane prepolymer (PUR), then reacting the polyurethane prepolymer (PUR) with the hydroxyl group of an epoxy resin to obtain a polyurethane-blocked modified epoxy resin (UE), and finally reacting with an unsaturated monocarboxylic acid to obtain a polyurethane-modified vinyl ester resin (VER). The preparation method of the invention not only blocks the flexible polyether segment into the resin structure, but also the presence of a carbamate bond increases the functionality of the vinyl ester resin. The resin casting obtained by the method has tensile strength and elongation at break increased to 72.73MPa and 12.51% respectively compared to the untoughened resin. However, the modification method has the problems of cumbersome synthesis steps, strict reaction temperature control, and difficult determination of isocyanate content. And the addition of a large amount of polyurethane flexible segments will also increase the viscosity of the resin and affect the curing speed of the casting.

[0004] Patent 202211380885.3 A toughened vinyl ester resin formula and its preparation method and application, using epoxy resin, inhibitor, catalyst, acrylic acid, and diluent as raw materials to synthesize vinyl ester resin; the invention uses diphenylmethane diisocyanate, polypropylene glycol, hydroxyethyl methacrylate, and catalyst as raw materials to synthesize polyurethane acrylate; vinyl ester resin, polyurethane acrylate and diaminodiphenyl sulfide, 1,1'-diaminoferrocene undergo amino-ene Michael addition reaction to obtain toughened vinyl ester resin. This method uses a large amount of DMF organic solvent in the preparation process, which is difficult to remove later, and too many polyurethane soft segments are introduced, and the DMF residue will plasticize, increasing toughness while sacrificing strength.

[0005] Patent 201911206917.6 discloses a method for synthesizing toughened modified vinyl ester resin. The method first obtains an isocyanate-terminated polyurethane prepolymer by reacting diisocyanate with a flexible diol, then introduces it into a bisphenol A type vinyl resin through a grafting reaction, and finally dissolves it in an olefin crosslinker to obtain a toughened vinyl resin. The resulting resin casting has an elongation at break of 15.03-22.18% and an impact strength of 31.24-43.18KJ / m 2 However, the introduction of a large number of polyurethane flexible segments by this synthesis method inevitably lowers the glass transition temperature of the material. The toughening effect is achieved at the expense of rigidity, and the tensile strength, tensile modulus and flexural strength of the material all decrease to varying degrees. Summary of the invention

[0006] In order to solve the above-mentioned problems existing in the vinyl ester resin in the prior art, the present invention provides a high-strength toughened epoxy vinyl ester resin composition and a preparation method thereof, wherein a functional olefin monomer containing tert-butyl hindered amine is introduced into epoxy vinyl ester, and the functional olefin monomer is used to prepare a modified resin having reversible dynamic hindered urea covalent cross-linking bond toughening through its high reactivity with isocyanate.

[0007] A high-strength toughened epoxy vinyl ester resin composition comprises the following raw materials in parts by weight:

[0008]

[0009] The modified epoxy vinyl ester resin comprises the following raw materials: 35-50% bisphenol A epoxy resin, 10-24% organic unsaturated acid, 0.1-0.5% catalyst, 0.03-0.1% inhibitor, 22-41% olefin crosslinking agent, and 2-12% functional olefin monomer.

[0010] The dynamic crosslinking agent is a compound of any one or more of hexamethylene diisocyanate, isophorone diisocyanate, toluene diisocyanate, and diphenylmethane diisocyanate; the mass percentage of the dynamic crosslinking agent is the mass percentage of the functional olefin monomer × 0.0027 × the average molar mass of the dynamic crosslinking agent. The purpose of limiting the amount of the dynamic crosslinking agent is to ensure that the dynamic crosslinking agent reacts completely with the functional olefin monomer without any excess residue.

[0011] The functional olefin monomer is tert-butylaminoethyl methacrylate.

[0012] The bisphenol A epoxy resin is a bisphenol A epoxy resin with an epoxy equivalent of 186 to 192 g / mol; the organic unsaturated acid is selected from any one of methacrylic acid and acrylic acid.

[0013] Preferably, the bisphenol A epoxy resin is selected from E51 or E44.

[0014] The catalyst is one or a combination of benzyldimethylamine, benzyltrimethylammonium bromide, tetramethylammonium chloride, imidazole, and triphenylphosphine; the inhibitor is any one of hydroquinone, methylhydroquinone, and para-benzoquinone; and the olefin crosslinking agent is any one or more of styrene, methyl acrylate, methyl methacrylate, and butyl acrylate.

[0015] The initiator is methyl ethyl ketone peroxide; the accelerator is cobalt isooctanoate solution.

[0016] The structural fragment of the above-mentioned high-strength toughened epoxy vinyl ester resin composition is shown in the following formula (1):

[0017]

[0018] Among them, x1+x2+x3+x4+...+x n =0.18~0.27,y1+y2+y3+y4+...+y n =0.17~0.48,z1+z2+...+z n =0.01~0.08.

[0019] The preparation method of a high-strength toughened epoxy vinyl ester resin composition comprises the following steps: (1) adding bisphenol A epoxy resin into a reaction bottle, passing nitrogen protection, maintaining stirring state, and gradually heating to 80-90°C; (2) then dripping a mixed solution consisting of an organic unsaturated acid, a catalyst, and an inhibitor at a speed of 2-3 d / s, and after the dripping is completed, heating and controlling the temperature at 100-120°C until the acid value drops to 10 mgKOH / g and the reaction is completed; (3) when the reactants are cooled to 70-80°C, adding an olefin crosslinking agent and a functional olefin monomer, stirring evenly, and obtaining a modified epoxy vinyl ester resin; (4) mixing the modified epoxy vinyl ester resin, an initiator, a accelerator, and a dynamic crosslinking agent to form a high-strength toughened epoxy vinyl ester resin composition.

[0020] The mixing method of the above step (4) is as follows: first add the accelerator and stir for 2 to 5 minutes under the ambient temperature of -5 to 40 degrees; then add the initiator and stir for 2 to 5 minutes; after standing for 5 to 10 minutes, finally add the dynamic crosslinking agent before molding and use, and stir for 2 to 15 minutes according to different ambient temperatures before molding.

[0021] Dynamic crosslinking agents are mainly used to react with functional olefin monomers in modified epoxy vinyl ester resins to generate dynamic hindered urea covalent crosslinking bonds.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] (1) The introduced functional olefin monomer tert-butylaminoethyl methacrylate plays a role in diluting and reducing the viscosity of the resin, and the obtained resin has a moderate viscosity. In addition, the high reactivity between tert-butylamine and isocyanate makes the curing speed of the casting faster than that of the conventional epoxy vinyl ester resin.

[0024] (2) The dynamic hindered urea covalent bond generated by the reaction is different from the traditional urea bond. Since the bulky tert-butyl side group replaces a hydrogen atom on the nitrogen, the orbital coplanarity of the amide bond is disturbed, which significantly reduces the bond energy of the amide bond, making the hindered urea group reversible and dynamic at room temperature. On the one hand, the introduction of dynamic cross-linking points increases the cross-linking degree of the resin, making the rigidity of the casting better than that of the usual vinyl resin; on the other hand, when the material is subjected to external force, the dynamic hindered urea bond will break first due to its lower bond energy than the covalent bond, thereby absorbing energy, dissipating stress, and improving the toughness of the vinyl resin.

[0025] (3) The high-strength toughened epoxy vinyl ester resin composition of the present invention can be quickly cured at room temperature, has excellent comprehensive performance, and has simultaneously improved rigidity (tensile strength, compressive strength) and toughness (elongation at break, impact strength). It can be used as the main resin of building structural adhesives, corrosion-resistant materials, and composite materials, and is widely used in the fields of construction, industry, transportation, etc. In addition, the modification method based on hindered amine dynamic bonds is also expected to be expanded to other engineering polymer materials. DETAILED DESCRIPTION

[0026] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solution 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 are within the scope of protection of the present invention.

[0027] The sources of raw materials used in each embodiment of the present application are shown in Table 1 below:

[0028] Table 1

[0029]

[0030]

[0031] In the following embodiments, the mixing method in the above step (4) is at room temperature. First, the accelerator is added and stirred for 5 minutes; then the initiator is added and stirred for 5 minutes; after standing for 5 minutes, the dynamic crosslinking agent is added before molding and used, and after stirring for 5 minutes, molding is completed.

[0032] Embodiment 1:

[0033] In a three-necked flask with a stirrer and a condenser, add 510g of E51, pass nitrogen protection, keep stirring, and gradually heat to 85°C. When the temperature rises to 80°C, start to drop a mixed solution consisting of 231g of methacrylic acid, 1g of benzyldimethylamine, 1.2g of benzyltrimethylammonium bromide, and 0.6g of p-benzoquinone at a rate of 2d / s. After the addition is completed, heat and control the temperature at 110°C until the acid value drops to 10mgKOH / g and the reaction is over. When the reactants are cooled to 80°C, add 180g of styrene, 70g of methyl methacrylate, and 40g of tert-butylaminoethyl methacrylate, and stir evenly to obtain hindered amine bond-modified epoxy vinyl ester resin.

[0034] Take 100g of hindered amine bond modified epoxy vinyl ester resin, add 1.5g of cobalt isooctanoate solution, 2.5g of methyl ethyl ketone peroxide, 0.8g of hexamethylene diisocyanate, and 1g of toluene diisocyanate in sequence, and the hindered amine bond modified high-strength toughened epoxy vinyl ester resin composition is formed. At room temperature, the mechanical properties are tested according to the requirements of GB / T50728-2008, and the results are as follows: gel time 10min, tensile strength 71.4MPa, compressive strength 96.3MPa, elongation at break 11.3%, impact strength 37.6KJ / m 2 .

[0035] Embodiment 2:

[0036] In a three-necked flask with a stirrer and a condenser, add 470g of E44, pass nitrogen protection, keep stirring, and gradually heat to 80°C. When the temperature rises to 80°C, start to drop a mixed solution consisting of 218g of methacrylic acid, 2.1g of imidazole, and 0.7g of methyl hydroquinone at a rate of 3d / s. After the dropwise addition is completed, heat and control the temperature at 120°C until the acid value drops to 10mgKOH / g and the reaction is completed. When the reactants are cooled to 75°C, add 400g of styrene, 80g of methyl acrylate, and 95g of tert-butylaminoethyl methacrylate, and stir evenly to obtain hindered amine bond-modified epoxy vinyl ester resin.

[0037] Take 100g of hindered amine bond modified epoxy vinyl ester resin, add 1.5g of cobalt isooctanoate solution, 2.5g of methyl ethyl ketone peroxide, and 4.5g of isophorone diisocyanate in sequence, and the hindered amine bond modified high-strength toughened epoxy vinyl ester resin composition is formed. At room temperature, the mechanical properties are tested according to the requirements of GB / T50728-2008, and the results are as follows: gel time 6min, tensile strength 74.2MPa, compressive strength 98.8MPa, elongation at break 9.1%, impact strength 33.2KJ / m 2 .

[0038] Embodiment 3:

[0039] In a three-necked flask with a stirrer and a condenser, add 430g of E44, pass nitrogen protection, keep stirring, and gradually heat to 80°C. When the temperature rises to 80°C, start to drop a mixed solution consisting of 195g of methacrylic acid, 1.2g of imidazole, 0.7g of benzyldimethylamine, and 0.6g of methylhydroquinone at a rate of 3d / s. After the addition is completed, heat and control the temperature at 100°C until the acid value drops to 10mgKOH / g, and the reaction is completed. When the reactants are cooled to 70°C, add 200g of styrene, 60g of methyl acrylate, 40g of methyl methacrylate, and 50g of tert-butylaminoethyl methacrylate, and stir evenly to obtain hindered amine bond modified epoxy vinyl ester resin.

[0040] Take 100g of hindered amine bond modified epoxy vinyl ester resin, add 1.5g of cobalt isooctanoate solution, 2.5g of methyl ethyl ketone peroxide, 1g of hexamethylene diisocyanate, and 1.9 of isophorone diisocyanate in sequence, and the hindered amine bond modified high-strength toughened epoxy vinyl ester resin composition is formed. At room temperature, the mechanical properties are tested according to the requirements of GB / T50728-2008, and the results are as follows: gel time 13min, tensile strength 68.6MPa, compressive strength 91.2MPa, elongation at break 10.3%, impact strength 34.5KJ / m 2 .

[0041] Embodiment 4:

[0042] In a three-necked flask with a stirrer and a condenser, add 350g of E51, pass nitrogen protection, keep stirring, and gradually heat to 90°C. When the temperature rises to 80°C, start to drop a mixed solution consisting of 158g of methacrylic acid, 1g of tetramethylammonium chloride, 0.6g of triphenylphosphine, and 0.5g of hydroquinone at a rate of 2d / s. After the addition is completed, heat and control the temperature at 110°C until the acid value drops to 10mgKOH / g and the reaction is over. When the reactants are cooled to 75°C, add 230g of styrene, 50g of butyl acrylate, and 60g of tert-butylaminoethyl methacrylate, and stir evenly to obtain hindered amine bond modified epoxy vinyl ester resin.

[0043] Take 100g of hindered amine bond modified epoxy vinyl ester resin, add 1.5g of cobalt isooctanoate solution, 2.5g of methyl ethyl ketone peroxide, and 4.7g of diphenylmethane diisocyanate in sequence, and the hindered amine bond modified high-strength toughened epoxy vinyl ester resin composition is formed. At room temperature, the mechanical properties are tested according to the requirements of GB / T50728-2008, and the results are as follows: gel time 8min, tensile strength 72.3MPa, compressive strength 96.6MPa, elongation at break 9.4%, impact strength 33.7KJ / m 2 .

[0044] Embodiment 5:

[0045] In a three-necked flask with a stirrer and a condenser, add 410g of E51, pass nitrogen protection, keep stirring, and gradually heat to 90°C. When the temperature rises to 80°C, start to drop a mixed solution consisting of 155g of acrylic acid, 1.7g of tetramethylammonium chloride, and 0.5g of p-benzoquinone at a rate of 2d / s. After the dropwise addition is completed, heat and control the temperature at 115°C until the acid value drops to 10mgKOH / g and the reaction is over. When the reactants are cooled to 70°C, add 280g of styrene, 70g of methyl methacrylate, and 30g of tert-butylaminoethyl methacrylate, and stir evenly to obtain hindered amine bond-modified epoxy vinyl ester resin.

[0046] Take 100g of hindered amine bond modified epoxy vinyl ester resin, add 1.5g of cobalt isooctanoate solution, 2.5g of methyl ethyl ketone peroxide, and 1.5g of toluene diisocyanate in sequence, and then form a hindered amine bond modified high-strength toughened epoxy vinyl ester resin composition. At room temperature, the mechanical properties test was carried out according to the requirements of GB / T50728-2008, and the results are as follows: gel time 12min, tensile strength 70.1MPa, compressive strength 94.2MPa, elongation at break 10.6%, impact strength 36.1KJ / m 2 .

[0047] Embodiment 6:

[0048] In a three-necked flask with a stirrer and a condenser, add 380g of E51, pass nitrogen protection, keep stirring, and gradually heat up to 85°C. When the temperature rises to 80°C, start to drop a mixed solution consisting of 172g of methacrylic acid, 1.8g of benzyldimethylamine, and 0.6g of hydroquinone at a rate of 3d / s. After the addition is completed, heat up and control the temperature at 110°C until the acid value drops to 10mgKOH / g and the reaction is completed. When the reactants are cooled to 80°C, add 300g of styrene, 100g of methyl methacrylate, and 40g of tert-butylaminoethyl methacrylate, and stir evenly to obtain hindered amine bond-modified epoxy vinyl ester resin.

[0049] Take 100g of hindered amine bond modified epoxy vinyl ester resin, add 1.5g of cobalt isooctanoate solution, 2.5g of methyl ethyl ketone peroxide, and 2g of hexamethylene diisocyanate in sequence, and the hindered amine bond modified high-strength toughened epoxy vinyl ester resin composition is formed. At room temperature, the mechanical properties are tested according to the requirements of GB / T50728-2008, and the results are as follows: gel time 10min, tensile strength 71.2MPa, compressive strength 95.1MPa, elongation at break 9.2%, impact strength 33.3KJ / m 2 .

[0050] Embodiment 7:

[0051] In a three-necked flask with a stirrer and a condenser, add 360g of E51, pass nitrogen protection, keep stirring, and gradually heat to 90°C. When the temperature rises to 80°C, start to drop a mixed solution consisting of 90g of acrylic acid, 1.4g of benzyltrimethylammonium bromide, and 0.45g of hydroquinone at a rate of 2d / s. After the dropwise addition is completed, heat and control the temperature at 120°C until the acid value drops to 10mgKOH / g and the reaction is over. When the reactants are cooled to 80°C, add 180g of styrene, 80g of methyl acrylate, and 45g of tert-butylaminoethyl methacrylate, and stir evenly to obtain hindered amine bond-modified epoxy vinyl ester resin.

[0052] Take 100g of hindered amine bond modified epoxy vinyl ester resin, add 1.5g of cobalt isooctanoate solution, 2.5g of methyl ethyl ketone peroxide, 1.2g of hexamethylene diisocyanate, 0.8g of diphenylmethane diisocyanate, and 1.4g of toluene diisocyanate in sequence, and the hindered amine bond modified high-strength toughened epoxy vinyl ester resin composition is formed. At room temperature, the mechanical properties are tested according to the requirements of GB / T50728-2008, and the results are as follows: gel time 9min, tensile strength 73.9MPa, compressive strength 95.3MPa, elongation at break 9.8%, impact strength 35.3KJ / m 2 .

[0053] Comparative Example 1:

[0054] In a three-necked flask with a stirrer and a condenser, add 510g of E51, pass nitrogen protection, keep stirring, and gradually heat to 85°C. When the temperature rises to 80°C, start to drop a mixed solution consisting of 231g of methacrylic acid, 1g of benzyldimethylamine, 1.2g of benzyltrimethylammonium bromide, and 0.6g of p-benzoquinone at a rate of 2d / s. After the addition is completed, heat and control the temperature at 110°C until the acid value drops to 10mgKOH / g and the reaction is over. When the reactants are cooled to 80°C, add 180g of styrene, 70g of methyl methacrylate, and 40g of tert-butylaminoethyl methacrylate, and stir evenly to obtain hindered amine bond-modified epoxy vinyl ester resin.

[0055] Take 100g of hindered amine bond modified epoxy vinyl ester resin, add 1.5g of cobalt isooctanoate solution and 2.5g of methyl ethyl ketone peroxide in sequence, without adding dynamic crosslinking agent, to obtain an untoughened hindered amine bond modified epoxy vinyl ester resin composition. At room temperature, mechanical properties were tested according to the requirements of GB / T50728-2008, and the results were as follows: gel time 19min, tensile strength 60.3MPa, compressive strength 84.3MPa, elongation at break 6.1%, impact strength 25.7KJ / m 2 .

[0056] Comparative Example 2:

[0057] In a three-necked flask with a stirrer and a condenser, add 510g of E51, pass nitrogen protection, keep stirring, and gradually heat to 85°C. When the temperature rises to 80°C, start to drop a mixed solution consisting of 231g of methacrylic acid, 1g of benzyldimethylamine, 1.2g of benzyltrimethylammonium bromide, and 0.6g of p-benzoquinone at a rate of 2d / s. After the dropwise addition is completed, heat and control the temperature at 110°C until the acid value drops to 10mgKOH / g and the reaction is completed. When the reactants are cooled to 80°C, add 220g of styrene and 70g of methyl methacrylate, and stir evenly to obtain hindered amine bond modified epoxy vinyl ester resin.

[0058] Take 100g of hindered amine bond modified epoxy vinyl ester resin, add 1.5g of cobalt isooctanoate solution, 2.5g of methyl ethyl ketone peroxide, 0.8g of hexamethylene diisocyanate, and 1g of toluene diisocyanate in sequence when using, and obtain an untoughened hindered amine bond modified epoxy vinyl ester resin composition. At room temperature, the mechanical properties test was carried out according to the requirements of GB / T50728-2008, and the results are as follows: gel time 18min, tensile strength 63.1MPa, compressive strength 86.5MPa, elongation at break 5.6%, impact strength 24.6KJ / m 2 .

[0059] Comparative Example 3:

[0060] In a three-necked flask with a stirrer and a condenser, add 510g of E51, pass nitrogen protection, keep stirring, and gradually heat to 85°C. When the temperature rises to 80°C, start to drop a mixed solution consisting of 231g of methacrylic acid, 1g of benzyldimethylamine, 1.2g of benzyltrimethylammonium bromide, and 0.6g of p-benzoquinone at a rate of 2d / s. After the addition is completed, heat and control the temperature at 110°C until the acid value drops to 10mgKOH / g and the reaction is completed. When the reactants are cooled to 80°C, add 220g of styrene and 70g of methyl methacrylate, stir evenly to obtain unmodified epoxy vinyl ester resin.

[0061] Take 100g of unmodified epoxy vinyl ester resin, add 1.5g of cobalt isooctanoate solution and 2.5g of methyl ethyl ketone peroxide in sequence, and obtain an untoughened and unmodified epoxy vinyl ester resin composition. At room temperature, the mechanical properties test was carried out according to the requirements of GB / T50728-2008, and the results are as follows: gel time 25min, tensile strength 62.3MPa, compressive strength 87.6MPa, elongation at break 5.9%, impact strength 26.9KJ / m 2 .

[0062] Comparative Example 4:

[0063] In a three-necked flask with a stirrer and a condenser, add 510g of E51, pass nitrogen protection, keep stirring, and gradually heat to 85°C. When the temperature rises to 80°C, start to drop a mixed solution consisting of 231g of methacrylic acid, 1g of benzyldimethylamine, 1.2g of benzyltrimethylammonium bromide, and 0.6g of p-benzoquinone at a rate of 2d / s. After the addition is completed, heat and control the temperature at 110°C until the acid value drops to 10mgKOH / g and the reaction is completed. When the reactants are cooled to 80°C, add 180g of styrene, 70g of methyl methacrylate, and 40g of 2-aminoethyl methacrylate, and stir evenly to obtain a modified epoxy vinyl ester resin.

[0064] Take 100g of modified epoxy vinyl ester resin, add 1.5g of cobalt isooctanoate solution, 2.5g of methyl ethyl ketone peroxide, 0.8g of hexamethylene diisocyanate, and 1g of toluene diisocyanate in sequence, and the modified epoxy vinyl ester resin composition is formed. At room temperature, the mechanical properties are tested according to the requirements of GB / T50728-2008, and the results are as follows: gel time 24min, tensile strength 58.7MPa, compressive strength 82.4MPa, elongation at break 5.9%, impact strength 23.2KJ / m 2 .

[0065] Comparative Example 5:

[0066] Take 100g of Shanghai Fengzhan bisphenol A epoxy vinyl ester resin 901, add 1.5g of cobalt isooctanoate solution, 2.5g of methyl ethyl ketone peroxide, 0.8g of hexamethylene diisocyanate, and 1g of toluene diisocyanate in sequence to obtain an epoxy vinyl ester resin composition. At room temperature, the mechanical properties were tested according to the requirements of GB / T50728-2008, and the results were as follows: gel time 18min, tensile strength 58.2MPa, compressive strength 88.9MPa, elongation at break 5.75%, impact strength 26.2KJ / m 2 .

[0067] Comparative Example 6:

[0068] Take 100g of Shanghai Fuchen Bisphenol A Epoxy Vinyl Ester Resin 854, add 1.5g of cobalt isooctanoate solution, 2.5g of methyl ethyl ketone peroxide, 0.8g of hexamethylene diisocyanate, and 1g of toluene diisocyanate in sequence to obtain an epoxy vinyl ester resin composition. At room temperature, the mechanical properties were tested according to the requirements of GB / T50728-2008, and the results were as follows: gel time 26min, tensile strength 57.2MPa, compressive strength 76.3MPa, elongation at break 6.3%, impact strength 27.5KJ / m 2 .

[0069] From the above test results, it can be seen that compared with the unmodified resin composition, the hindered amine bond modified high-strength toughened epoxy vinyl ester resin composition prepared in the present application has a faster curing speed, and after curing, the tensile strength of the resin casting is 68.6-74.2MPa, the compressive strength is 91.2-98.8MPa, the elongation at break is 9.1-11.3%, and the impact strength is 33.2-37.6KJ / m 2 , flexibility and strength have been significantly improved.

[0070] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A high-strength toughened epoxy vinyl ester resin composition, characterized in that: The invention comprises the following raw materials in parts by weight: The modified epoxy vinyl ester resin comprises the following raw materials: 35-50% bisphenol A epoxy resin, 10-24% organic unsaturated acid, 0.1-0.5% catalyst, 0.03-0.1% inhibitor, 22-41% olefin crosslinking agent, and 2-12% functional olefin monomer.

2. A high-strength toughened epoxy vinyl ester resin composition according to claim 1, characterized in that: The dynamic crosslinking agent is a compound of any one or more of hexamethylene diisocyanate, isophorone diisocyanate, toluene diisocyanate, and diphenylmethane diisocyanate; the mass percentage of the dynamic crosslinking agent is the mass percentage of the functional olefin monomer×0.0027×the average molar mass of the dynamic crosslinking agent.

3. A high-strength toughened epoxy vinyl ester resin composition according to claim 1, characterized in that: The functional olefin monomer is tert-butylaminoethyl methacrylate.

4. A high-strength toughened epoxy vinyl ester resin composition according to claim 1, characterized in that: The bisphenol A epoxy resin refers to a bisphenol A epoxy resin with an epoxy equivalent of 186 to 192 g / mol; the organic unsaturated acid is selected from any one of methacrylic acid and acrylic acid.

5. A high-strength toughened epoxy vinyl ester resin composition according to claim 1, characterized in that: The catalyst is one or a combination of benzyldimethylamine, benzyltrimethylammonium bromide, tetramethylammonium chloride, imidazole, and triphenylphosphine; the inhibitor is any one of hydroquinone, methyl hydroquinone, and p-benzoquinone; and the olefin crosslinking agent is any one or more of styrene, methyl acrylate, methyl methacrylate, and butyl acrylate.

6. A high-strength toughened epoxy vinyl ester resin composition according to claim 1, characterized in that: The initiator is methyl ethyl ketone peroxide; the accelerator is cobalt isooctanoate liquid.

7. A method for preparing a high-strength toughened epoxy vinyl ester resin composition according to any one of claims 1 to 6, characterized in that: The method comprises the following steps: (1) adding bisphenol A epoxy resin into a reaction bottle, passing nitrogen for protection, maintaining stirring state, and gradually heating up to 80-90 DEG C; (2) then dripping a mixed solution consisting of an organic unsaturated acid, a catalyst, and an inhibitor at a speed of 2-3 d / s, and after the dripping is completed, heating up and controlling the temperature at 100-120 DEG C until the acid value drops to 10 mgKOH / g and the reaction is completed; (3) when the reactants are cooled to 70-80 DEG C, adding an olefin crosslinking agent and a functional olefin monomer, stirring evenly, and obtaining a modified epoxy vinyl ester resin; (4) mixing the modified epoxy vinyl ester resin, an initiator, a accelerator, and a dynamic crosslinking agent to form a high-strength toughened epoxy vinyl ester resin composition.

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