Epoxy resin cured product and preparation method therefor

Abstract

Disclosed in the present invention are an epoxy resin cured product and a preparation method therefor. The epoxy resin cured product of the present invention is obtained by curing an epoxy resin matrix, an epoxy resin toughening modifier, and a curing agent. The epoxy resin toughening modifier is a polyether ester amide multi-block copolymer comprising three block components, i.e., aliphatic polyether, polyester, and polyamide, the multi-block copolymer can be dissolved in the epoxy resin matrix at normal temperature or while heating to obtain a corresponding modified epoxy resin, and during the curing of the epoxy resin, the multi-block copolymer precipitates and undergoes microphase separation. Due to a small microphase separation size, the transparency of the epoxy resin cured product is good. After the epoxy resin toughening modifier of the present invention is added, the toughness, impact strength and tensile strength of the epoxy resin cured product are significantly improved, the problems of insufficient toughness, high brittleness and the like of the epoxy resin cured product and a composite material comprising same are effectively alleviated, and a high-transparency epoxy resin can be prepared.

Description

An epoxy resin cured product and its preparation method Technical Field

[0001] This invention relates to the field of epoxy resins, and in particular to an epoxy resin cured product and its preparation method. Background Technology

[0002] Epoxy resins are among the most widely used thermosetting materials due to their excellent mechanical and chemical stability, heat resistance, corrosion resistance, electrical insulation, and bonding properties. They are extensively applied in anti-corrosion coatings, adhesives, electronic packaging materials, electrical insulation materials, and high-performance composite materials. However, the highly cross-linked structure of cured epoxy resins results in poor impact resistance, poor fracture toughness, and poor fatigue resistance, severely limiting their application in certain important fields such as advanced composite materials, structural adhesives, and ultra-low temperature toughness materials. Therefore, toughening modification of epoxy resins has become a research hotspot.

[0003] Currently, based on the toughening mechanism, epoxy resin toughening systems can be divided into homogeneous toughening systems and heterogeneous toughening systems. Homogeneous toughening systems are mainly achieved by introducing flexible segments onto the epoxy resin. This method not only presents certain difficulties in the design and synthesis of raw materials but also significantly reduces the strength of the epoxy resin. Heterogeneous toughening systems involve phase separation between the modifier and the epoxy resin matrix, and are typically multiphase structures with phase sizes on the submicron or micron scale.

[0004] Block copolymers can contain both miscible and immiscible epoxy resin blocks, providing a new method for toughening epoxy resins. Significant toughening effects can be achieved by adjusting the composition and structure of the block copolymers.

[0005] Currently, there is considerable research on the use of diblock and triblock copolymers as toughening agents for epoxy resins. For example, CN115160515A discloses the application of an amphiphilic liquid crystal block copolymer as a toughening agent for epoxy resins. This amphiphilic liquid crystal block copolymer is obtained by atom transfer radical polymerization or reversible addition-fragmentation chain transfer solution polymerization of polyethylene glycol methyl ether methacrylate or ethyl 2-(dimethylamino)methacrylate with biphenyl-based or diphenylethylene-based liquid crystal monomers. Although this toughening system exhibits good toughening effects on epoxy resins, its synthesis process consumes a large amount of organic solvents, resulting in high preparation costs and environmental unfriendliness, making it difficult to apply in actual production processes for toughening epoxy resins.

[0006] CN102348757A discloses a thermosetting composition containing a combination of amphiphilic block copolymers and polyols, and its thermosetting product. The epoxy resin toughening agent used is concentrated in amphiphilic polyether block copolymers having both miscible and immiscible blocks of epoxy resin, which exhibit good toughening effects on epoxy resins. However, this invention does not describe the toughening effect of multi-block copolymers in epoxy resins. Furthermore, the phase separation scale of diblock copolymers is large, limiting their toughening and modification effects on epoxy resins.

[0007] Compared to diblock copolymers, multiblock copolymers exhibit better toughening and modification effects because their blocks can shuttle between multiple microregions. Furthermore, the smaller microphase separation scale results in weaker light scattering, leading to higher transparency in the cured epoxy resin.

[0008] Based on the above analysis, there is an urgent need to develop a multi-block copolymer as a toughening modifier for epoxy resins, so as to apply it to the toughening of epoxy resins, achieve a significant improvement in their tensile strength and impact strength, and achieve high transparency. Summary of the Invention

[0009] To address the aforementioned technical problems, this invention provides an epoxy resin cured product and its preparation method. The epoxy resin is toughened and modified using a multi-block copolymer, which is a polyether ester amide multi-block copolymer composed of aliphatic polyether, polyester, and polyamide. The polyether and polyester blocks exhibit good solubility in the epoxy resin matrix. This multi-block copolymer also possesses certain compatibility with the epoxy resin matrix, dissolving in it at room temperature or under heating to obtain a modified epoxy resin matrix. During epoxy resin curing, the multi-block copolymer precipitates and undergoes microphase separation. Due to the small scale of microphase separation in the system, a high-strength and tough epoxy resin cured product with good transparency can be prepared. After adding the epoxy resin toughening modifier of this invention, the toughness, impact strength, and tensile strength of the epoxy resin cured product are significantly improved without significantly affecting its transparency.

[0010] This invention is achieved through the following technical solution:

[0011] The first objective of this invention is to provide an epoxy resin cured product obtained by curing a modified epoxy resin, wherein the modified epoxy resin comprises the following components: an epoxy resin matrix, an epoxy resin toughening modifier, and a curing agent.

[0012] In one embodiment of the present invention, the epoxy resin toughening modifier is a polyether ester amide multiblock copolymer; the polyether ester amide multiblock copolymer is composed of three blocks: aliphatic polyether, aliphatic polyester and aliphatic polyamide.

[0013] The aliphatic polyether content is 60wt% to 90wt%; the aliphatic polyester content is 10wt% to 30wt%; the aliphatic polyamide content is 1wt% to 12wt%, and the sum of the contents of all components is 100wt%.

[0014] In one embodiment of the present invention, the epoxy resin matrix is ​​selected from bisphenol A type epoxy resins with an epoxy value of 0.1 to 0.6, including but not limited to one or more of E-12, E-44, E-51 and BE-188EL.

[0015] In one embodiment of the present invention, the curing agent is an amine curing agent; the amine curing agent is selected from one or more of ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine and isophoronediamine.

[0016] In one embodiment of the present invention, the chemical structural formula of the polyether ester amide multiblock copolymer is as follows:

[0017] Wherein, a is any integer from 2 to 6; b is any integer from 2 to 11; c is any integer from 2 to 4; d is any integer from 5 to 12; e is any integer from 4 to 68; f, g, and h are determined by the contents of aliphatic polyester, aliphatic polyether, and aliphatic polyamide, respectively; the block content of the aliphatic polyether is 60wt% to 90wt%; the block content of the aliphatic polyester is 10wt% to 30wt%; the block content of the aliphatic polyamide is 1wt% to 12wt%, and the sum of the contents of each component is 100wt%; the number average molecular weight of the multiblock copolymer is 6000g / mol to 50000g / mol.

[0018] In one embodiment of the present invention, the aliphatic polyether is preferably one or more of polyethylene oxide and polytetrahydrofuran; the number average molecular weight of the polyether block is 200 g / mol to 3000 g / mol.

[0019] In one embodiment of the invention, the aliphatic polyester is a polyaliphatic diacid glycol ester, preferably one or more selected from polyethylene adipate, polybutylene succinate, polyethylene tridecanoate, and polyethylene dodecanoate.

[0020] In one embodiment of the invention, the aliphatic polyamide is preferably one or more of nylon 1013, nylon 613, nylon 1213, nylon 104 and nylon 1012.

[0021] In one embodiment of the present invention, the mass ratio of the epoxy resin matrix to the epoxy resin toughening modifier is 200:1 to 10:1; the molar ratio of the amount of curing agent to the epoxy value of the epoxy resin matrix is ​​2:1 to 1:2, preferably 1:1.

[0022] The second objective of this invention is to provide a method for preparing a modified epoxy resin cured product, comprising the following steps: mixing an epoxy resin matrix with an epoxy resin toughening modifier, heating to 60°C to 150°C, stirring for 20 min to 1 h, mixing evenly, and cooling to room temperature; adding a curing agent and mixing evenly, and then heating and curing in a mold to obtain the epoxy resin cured product.

[0023] The technical solution of the present invention has the following advantages compared with the prior art:

[0024] 1. This invention provides an epoxy resin cured product and its preparation method. The epoxy resin toughening modifier proposed in this invention is a polyether ester amide multi-block copolymer. The polyether and polyester blocks, as flexible blocks, have good compatibility with the epoxy resin matrix, providing good flexibility and impact strength; while the polyamide blocks have poor compatibility with the epoxy resin matrix. Therefore, the toughening modifier of this invention can maintain good compatibility in the epoxy resin matrix, effectively improving its dispersion effect in the epoxy resin matrix, and can also precipitate and undergo microphase separation during epoxy resin curing, achieving a significant improvement in the toughness, impact strength, and tensile strength of the epoxy resin cured product.

[0025] 2. When the epoxy resin toughening modifier of the present invention is applied to the epoxy resin, the microphase separation scale in the system is very small, resulting in good transparency of the cured epoxy resin and without affecting the transparency of the epoxy resin. Attached Figure Description

[0026] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein...

[0027] Figure 1 is a stress-strain curve of the epoxy resin cured product in Example 1 of the present invention;

[0028] Figure 2 is a stress-strain curve of the epoxy resin cured product in Example 3 of the present invention;

[0029] Figure 3 is a stress-strain curve of the epoxy resin cured product in Example 4 of the present invention;

[0030] Figure 4 is a stress-strain curve of the epoxy resin cured product in Comparative Example 1 of the present invention.

[0031] Figure 5 is a comparison of the transparency of epoxy resin cured casting samples in the embodiments of the present invention;

[0032] Figure 6 is a comparison of the impact and tensile properties of the epoxy resin cured product in the embodiment of the present invention and the epoxy resin cured product in Comparative Example 1. Detailed Implementation

[0033] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0034] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, and the materials and reagents used are commercially available.

[0035] The CAS numbers of the organic reagents used in this invention are listed below:

[0036] Table 1

[0037] In the following embodiments of the present invention, the polyether ester amide multiblock copolymer is prepared by ring-opening-condensation cascade polymerization reaction. For specific preparation methods, please refer to patent CN116425983B - A high-impact polyether ester amide thermoplastic elastomer and its preparation method.

[0038] The polyether ester amide multiblock copolymer mBCP-1 was prepared by mixing musk T (10.0 g), polyethylene glycol (20.0 g, molecular weight 2000 g / mol), 1,10-decanediamine (0.6 g), and 15.0 μL of tetrabutyl titanate, under nitrogen purging and mechanical stirring, and reacting at 220 °C for 60 min. Quantitative nuclear magnetic resonance (NMR) spectroscopy of mBCP-1 revealed that the polyester block was polyethylene tridecanoate (PEB) with a content of 21%; the polyether block was polyethylene oxide (PEO) with a content of 73%; and the polyamide block was nylon 1013 with a content of 6%. The molecular weight of mBCP-1 was 6.5 kg / mol.

[0039] The polyether ester amide multiblock copolymer mBCP-2 was prepared by mixing musk T (10.0 g), polyethylene glycol (20.0 g, molecular weight 2000 g / mol), 1,10-decanediamine (0.6 g), and 15.0 μL of tetrabutyl titanate, under nitrogen purging, mechanical stirring, heating to 240 °C, and vacuum reaction for 60 min. Quantitative nuclear magnetic resonance (NMR) spectroscopy of mBCP-2 revealed that the polyester block was polyethylene tridecanoate (PEB) with a content of 25%; the polyether block was polyethylene oxide (PEO) with a content of 72%; and the polyamide block was nylon 1013 with a content of 3%. The molecular weight of mBCP-2 was 21.1 kg / mol.

[0040] The preparation method of the polyether ester amide multiblock copolymer mBCP-3 is similar to that of mBCP-2, the only difference being that 1,6-hexanediamine is used instead of 1,10-decanediamine in equal mass. Quantitative nuclear magnetic resonance (NMR) spectroscopy of mBCP-3 revealed that the polyester block is polyethylene tridecanoate (PEB) with a content of 16%; the polyether block is polyethylene oxide (PEO) with a content of 80%; and the polyamide block is nylon 613 with a content of 4%. The molecular weight of mBCP-3 is 28.8 kg / mol.

[0041] The preparation method of the polyether ester amide multiblock copolymer mBCP-4 is similar to that of mBCP-1, except that it is prepared by mixing musk T (10.0 g), polyethylene glycol (30.0 g, molecular weight 3000 g / mol), 1,10-decanediamine (0.8 g), and 20.0 μL of tetrabutyl titanate. Quantitative nuclear magnetic resonance (NMR) spectroscopy of mBCP-4 revealed that the polyester block is polyethylene tridecanoate (PEB) with a content of 13%; the polyether block is polyethylene oxide (PEO) with a content of 83%; and the polyamide block is nylon 1013 with a content of 4%. The molecular weight of mBCP-4 is 11.7 kg / mol.

[0042] The preparation method of the polyether ester amide multiblock copolymer mBCP-5 is similar to that of mBCP-1, the only difference being that it is prepared by mixing musk T (10.0 g), polyethylene glycol (20.0 g, molecular weight 600 g / mol), 1,12-dodecanediamine (0.6 g), and 15.0 μL of tetrabutyl titanate. Quantitative nuclear magnetic resonance (NMR) spectroscopy of mBCP-5 revealed that the polyester block is polyethylene tridecanoate (PEB) with a content of 22%; the polyether block is polyethylene oxide (PEO) with a content of 75%; the polyamide block is nylon 1213 with a content of 3%; and the molecular weight of mBCP-5 is 15.9 kg / mol.

[0043] The preparation method of the polyether ester amide multiblock copolymer mBCP-6 is similar to that of mBCP-1, the only difference being that cyclic oligobutylene succinate is used instead of musk T in equal mass. Quantitative nuclear magnetic resonance (NMR) spectroscopy of mBCP-6 revealed that the polyester block was polybutylene succinate (PBS) at a content of 27%; the polyether block was polyethylene oxide (PEO) at a content of 70%; and the polyamide block was nylon 104 at a content of 3%. The intrinsic viscosity of mBCP-6 was 0.32 dL / g.

[0044] The preparation method of the polyether ester amide multiblock copolymer mBCP-7 is similar to that of mBCP-1, the only difference being that it is prepared by mixing musk T (10.0 g), polyethylene glycol (20.0 g, molecular weight 2000 g / mol), 1,10-decanediamine (1.5 g), and 15.0 μL of tetrabutyl titanate. Quantitative nuclear magnetic resonance (NMR) spectroscopy of mBCP-7 revealed that the polyester block is polyethylene tridecanoate (PEB) with a content of 18%; the polyether block is polyethylene oxide (PEO) with a content of 71%; and the polyamide block is nylon 1013 with a content of 11%. The molecular weight of mBCP-7 is 6.1 kg / mol.

[0045] The preparation method of the polyether ester amide multiblock copolymer mBCP-8 is similar to that of mBCP-1, with the only difference being that it is prepared by mixing 10.0 g of zen musk, 20.0 g of polytetrahydrofuran diol (mt. 1000 g / mol), 0.6 g of 1,10-decanediamine, and 15.0 μL of tetrabutyl titanate. Quantitative nuclear magnetic resonance (NMR) spectroscopy of mBCP-8 revealed that the polyester block is polyethylene dodecanoate (PED) with a content of 18%; the polyether block is polytetrahydrofuran (PTMO) with a content of 78%; the polyamide block is nylon 1012 with a content of 4%; and the molecular weight of mBCP-8 is 12.1 kg / mol.

[0046] The preparation method of the polyether ester amide multiblock copolymer mBCP-9 is similar to that of mBCP-2, with the only difference being that it is prepared by mixing musk T (16.5 g), polytetrahydrofuran diol (20.0 g, molecular weight 1000 g / mol), 1,10-decanediamine (3.5 g), and 8.0 μL of tetrabutyl titanate. Quantitative nuclear magnetic resonance (NMR) spectroscopy of mBCP-9 revealed that the polyester block is polyethylene tridecanoate (PEB) with a content of 21%; the polyether block is polytetrahydrofuran (PTMO) with a content of 60%; and the polyamide block is nylon 1013 with a content of 19%.

[0047] The preparation method of the polyether ester amide multiblock copolymer mBCP-10 is similar to that of mBCP-1, the only difference being that it is prepared by mixing musk T (25.8 g), polytetrahydrofuran diol (3.0 g, molecular weight 1000 g / mol), 1,10-decanediamine (4.2 g), and 6.0 μL of tetrabutyl titanate. Quantitative nuclear magnetic resonance (NMR) spectroscopy of mBCP-10 revealed that the polyester block is polyethylene tridecanoate (PEB) with a content of 61%; the polyether block is polytetrahydrofuran (PTMO) with a content of 11%; and the polyamide block is nylon 1013 with a content of 28%.

[0048] The preparation method of the polyether ester amide multiblock copolymer mBCP-11 is similar to that of mBCP-1, the only difference being that it is prepared by mixing musk T (16.5 g), polyethylene glycol (10.0 g, molecular weight 2000 g / mol), 1,10-decanediamine (3.5 g), and 6.0 μL of tetrabutyl titanate. Quantitative nuclear magnetic resonance (NMR) spectroscopy of mBCP-11 revealed that the polyester block is polyethylene tridecanoate (PEB) with a content of 41%; the polyether block is polyethylene oxide (PEO) with a content of 32%; and the polyamide block is nylon 1013 with a content of 27%.

[0049] In the following embodiments of the present invention, the intrinsic viscosity of the product was measured using an Ubbelohde viscometer, with m-cresol as the solvent and a temperature of 25°C.

[0050] In the following embodiments of the present invention, the tensile properties of the epoxy resin cured product were tested using an Instron-3365 universal testing machine (tensile rate: 10 mm / min, temperature: 20.0℃, humidity: 70.0%).

[0051] In the following embodiments of the present invention, the notched impact performance of simply supported beam epoxy resin cured products was tested using an FPP-01A impact testing machine in accordance with the GB / T 2567-2021 standard.

[0052] In the following embodiments of the present invention, the transmittance of epoxy resin cured products was tested using a Shimadzu UV-3150UV-vis spectrophotometer (temperature: 25°C, wavelength: 600nm).

[0053] Example 1

[0054] This embodiment provides a method for preparing epoxy resin cured products, the specific steps of which are as follows:

[0055] In this embodiment, the epoxy resin toughening modifier is a polyether ester amide multiblock copolymer mBCP-1.

[0056] 12.0g of BE-188EL epoxy resin was mixed with 0.60g of mBCP-1, heated to 70℃, stirred for 30min, and mixed evenly. The mixture was then cooled to room temperature. 2.64g of isophorone diamine was added and mixed evenly. The mixture was then cured at 40℃ for 1h, and then at 80℃, 120℃, and 160℃ for 2h in sequence to obtain epoxy resin cured product EP-1. Its stress-strain curve is shown in Figure 1.

[0057] The impact and tensile properties of the obtained epoxy resin cured products were tested, and the results are shown in Table 2. The light transmittance of epoxy resin cured product EP-1 was measured to be 94% compared to pure epoxy resin (comparative example EP).

[0058] Example 2

[0059] This embodiment provides a method for preparing an epoxy resin cured product, which is the same as the epoxy resin toughening modifier used in Example 1, except that: 12.0g of BE-188EL epoxy resin is mixed with 0.24g of mBCP-1, heated to 70°C, stirred for 1 hour, mixed evenly, and cooled to room temperature; 2.64g of isophorone diamine is added and mixed evenly, and then cured at 40°C for 1 hour, and then cured at 80°C, 120°C, and 160°C for 2 hours in sequence to obtain epoxy resin cured product EP-2.

[0060] The impact and tensile properties of the obtained epoxy resin cured product were tested, and the results are shown in Table 2.

[0061] Example 3

[0062] This embodiment provides a method for preparing an epoxy resin cured product, which is the same as the epoxy resin toughening modifier used in Example 1, except that: 12.0g of BE-188EL epoxy resin is mixed with 0.12g of mBCP-1, heated to 70℃, stirred for 20min, mixed evenly, and cooled to room temperature; 2.64g of isophorone diamine is added and mixed evenly, and then cured at 40℃ for 1h, and then at 80℃, 120℃, and 160℃ for 2h respectively to obtain epoxy resin cured product EP-3, whose stress-strain curve is shown in Figure 2.

[0063] The impact and tensile properties of the obtained epoxy resin cured product were tested, and the results are shown in Table 2.

[0064] Example 4

[0065] This embodiment provides a method for preparing epoxy resin cured products, the specific steps of which are as follows:

[0066] In this embodiment, the epoxy resin toughening modifier is a polyether ester amide multiblock copolymer mBCP-2.

[0067] 12.0g of BE-188EL epoxy resin was mixed with 0.60g of mBCP-2, heated to 130℃, stirred for 1h, and mixed evenly. The mixture was then cooled to room temperature. 2.64g of isophorone diamine was added and mixed evenly. The mixture was then cured at 40℃ for 1h, and then at 80℃, 120℃, and 160℃ for 2h in sequence to obtain epoxy resin cured product EP-4. Its stress-strain curve is shown in Figure 3.

[0068] The impact and tensile properties of the obtained epoxy resin cured products were tested, and the results are shown in Table 2. The light transmittance of epoxy resin cured product EP-4 was measured to be 83% compared with pure epoxy resin (comparative example EP).

[0069] Example 5

[0070] This embodiment provides a method for preparing epoxy resin cured products, the specific steps of which are as follows:

[0071] In this embodiment, the epoxy resin toughening modifier is a polyether ester amide multiblock copolymer mBCP-3.

[0072] The preparation process of the epoxy resin cured product is similar to that in Example 4, except that toughening agent mBCP-2 is replaced with toughening agent mBCP-3 of equal mass to obtain epoxy resin cured product EP-5.

[0073] The obtained epoxy resin cured products were subjected to impact and tensile property tests, and the results are shown in Table 2. The light transmittance of epoxy resin cured product EP-5 was measured to be 88% compared with pure epoxy resin (comparative example EP).

[0074] Example 6

[0075] This embodiment provides a method for preparing epoxy resin cured products, the specific steps of which are as follows:

[0076] In this embodiment, the epoxy resin toughening modifier is a polyether ester amide multiblock copolymer mBCP-4.

[0077] The preparation process of the epoxy resin cured product is similar to that in Example 1, except that toughening agent mBCP-1 is replaced with toughening agent mBCP-4 of equal mass to obtain epoxy resin cured product EP-6.

[0078] The impact and tensile properties of the obtained epoxy resin cured products were tested, and the results are shown in Table 2. The light transmittance of epoxy resin cured product EP-6 was measured to be 94% compared to pure epoxy resin (comparative example EP).

[0079] Example 7

[0080] This embodiment provides a method for preparing epoxy resin cured products, the specific steps of which are as follows:

[0081] In this embodiment, the epoxy resin toughening modifier is a polyether ester amide multiblock copolymer mBCP-5.

[0082] The preparation process of the epoxy resin cured product is similar to that in Example 4, except that toughening agent mBCP-2 is replaced with toughening agent mBCP-5 of equal mass to obtain epoxy resin cured product EP-7.

[0083] The impact and tensile properties of the obtained epoxy resin cured product were tested, and the results are shown in Table 2.

[0084] Example 8

[0085] This embodiment provides a method for preparing epoxy resin cured products, the specific steps of which are as follows:

[0086] In this embodiment, the epoxy resin toughening modifier is polyether ester amide multiblock copolymer mBCP-6.

[0087] The preparation process of the epoxy resin cured product is similar to that in Example 1, except that toughening agent mBCP-1 is replaced with toughening agent mBCP-6 of equal mass to obtain epoxy resin cured product EP-8.

[0088] The obtained epoxy resin cured products were subjected to impact and tensile property tests, and the results are shown in Table 2. The light transmittance of epoxy resin cured product EP-8 was measured to be 89% compared with pure epoxy resin (comparative example EP).

[0089] Example 9

[0090] This embodiment provides a method for preparing epoxy resin cured products, the specific steps of which are as follows:

[0091] In this embodiment, the epoxy resin toughening modifier is polyether ester amide multiblock copolymer mBCP-7.

[0092] The preparation process of the epoxy resin cured product is similar to that in Example 1, except that toughening agent mBCP-1 is replaced with toughening agent mBCP-7 of equal mass to obtain epoxy resin cured product EP-9.

[0093] The impact and tensile properties of the obtained epoxy resin cured product were tested, and the results are shown in Table 2.

[0094] Example 10

[0095] This embodiment provides a method for preparing epoxy resin cured products, the specific steps of which are as follows:

[0096] In this embodiment, the epoxy resin toughening modifier is polyether ester amide multiblock copolymer mBCP-8.

[0097] The preparation process of the epoxy resin cured product is similar to that in Example 4, except that toughening agent mBCP-2 is replaced with toughening agent mBCP-8 of equal mass to obtain epoxy resin cured product EP-10.

[0098] The impact and tensile properties of the obtained epoxy resin cured product were tested, and the results are shown in Table 2.

[0099] Comparative Example 1

[0100] This comparative example provides a method for preparing epoxy resin cured products, the specific steps of which are as follows:

[0101] 12.0g of BE-188EL epoxy resin was mixed with 2.64g of isophorone diamine. After the mixture was homogeneous, it was cured at 40℃ for 1h, and then cured at 80℃, 120℃ and 160℃ for 2h in sequence to obtain epoxy resin cured product EP. Its stress-strain curve is shown in Figure 4.

[0102] The impact and tensile properties of the obtained epoxy resin cured products were tested, and the results are shown in Table 2. As shown in Figure 5, the light transmittance of the modified epoxy resin cured products such as EP-1, EP-6, and EP-8 is close to that of the comparative example, indicating that the epoxy resin still maintains good light transmittance after the addition of toughening agents.

[0103] Comparative Example 2

[0104] The polyether ester amide multiblock copolymer provided in this comparative example is polyether ester amide multiblock copolymer mBCP-9. 12.0 g of BE-188EL epoxy resin was mixed with 0.60 g of mBCP-9, heated to 150°C, and stirred for 2 hours. mBCP-9 is incompatible with the epoxy resin matrix and cannot toughen or modify the epoxy resin.

[0105] Comparative Example 3

[0106] The polyether ester amide multiblock copolymer provided in this comparative example is polyether ester amide multiblock copolymer mBCP-10.

[0107] 12.0g of BE-188EL epoxy resin was mixed with 0.60g of mBCP-10, heated to 150℃, and stirred for 2h. mBCP-10 was incompatible with the epoxy resin matrix and could not toughen or modify the epoxy resin.

[0108] Comparative Example 4

[0109] The polyether ester amide multiblock copolymer provided in this comparative example is polyether ester amide multiblock copolymer mBCP-11.

[0110] 12.0g of BE-188EL epoxy resin was mixed with 0.60g of mBCP-11, heated to 150℃, and stirred for 2 hours. mBCP-11 was incompatible with the epoxy resin matrix and could not toughen or modify the epoxy resin.

[0111] Table 2 Impact toughness and tensile strength of epoxy resin materials

[0112] Impact strength is used to characterize the toughness of epoxy resin cured products. As shown in Table 2, after adding the toughening agent of the present invention, as shown in Examples 1-10, the toughness and strength of the epoxy resin cured products are significantly improved. The impact strength can be increased by more than 100%, and the strength can be increased by more than 40%, as shown in Figure 6. Obviously, the above examples are merely illustrative and not intended to limit the implementation. For those skilled in the art, other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all embodiments here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. An epoxy resin cured product, characterized by, It is obtained by curing modified epoxy resin; the modified epoxy resin comprises the following components: epoxy resin matrix, epoxy resin toughening modifier and curing agent; The epoxy resin toughening modifier is a polyether ester amide multiblock copolymer; the polyether ester amide multiblock copolymer is composed of three blocks: aliphatic polyether, aliphatic polyester and aliphatic polyamide; The aliphatic polyether content is 60wt% to 90wt%; the aliphatic polyester content is 10wt% to 30wt%; the aliphatic polyamide content is 1wt% to 12wt%, and the sum of the contents of all components is 100wt%.

2. The epoxy resin cured product according to claim 1, characterized by The epoxy resin matrix is ​​selected from bisphenol A type epoxy resin with an epoxy value of 0.1 to 0.6; the bisphenol A type epoxy resin is selected from one or more of E-12, E-44, E-51 and BE-188EL.

3. The epoxy resin cured product according to claim 1, characterized by The curing agent is an amine curing agent; the amine curing agent is selected from one or more of ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine and isophoronediamine.

4. The epoxy resin cured product according to claim 1, characterized in that, The chemical structural formula of the polyether ester amide multiblock copolymer is shown below: Wherein, a is any integer from 2 to 6; b is any integer from 2 to 11; c is any integer from 2 to 4; d is any integer from 5 to 12; e is any integer from 4 to 68; f, g, and h are determined by the contents of the aliphatic polyester, aliphatic polyether, and aliphatic polyamide, respectively; and the number-average molecular weight of the multiblock copolymer is 6000 g / mol to 50000 g / mol.

5. The epoxy resin cured product according to claim 1, characterized in that, The aliphatic polyether is polyethylene oxide and / or polytetrahydrofuran; the number average molecular weight of the aliphatic polyether is 200 g / mol to 3000 g / mol.

6. The epoxy resin cured product according to claim 1, characterized in that, The aliphatic polyester is a polyaliphatic diacid glycol ester; the polyaliphatic diacid glycol ester is selected from one or more of polyethylene adipate, polybutylene succinate, polyethylene tridecanoate, and polyethylene dodecanoate.

7. The epoxy resin cured product according to claim 1, characterized in that, The aliphatic polyamide is selected from one or more of nylon 1013, nylon 613, nylon 1213, nylon 104, and nylon 1012.

8. The epoxy resin cured product according to claim 1, characterized in that, The mass ratio of the epoxy resin matrix to the epoxy resin toughening modifier is 200:1 to 10:1; And / or, the molar ratio of the amount of curing agent to the epoxy value of the epoxy resin matrix is ​​2:1 to 1:

2.

9. The epoxy resin cured product according to claim 1, characterized in that, The light transmittance of the cured epoxy resin is greater than 80% of that of pure epoxy resin.

10. A method for preparing epoxy resin cured products, characterized in that, The method includes the following steps: mixing epoxy resin matrix with epoxy resin toughening modifier, heating to 60℃~150℃, stirring for 20min~1h, mixing evenly, and cooling to room temperature; adding curing agent and mixing evenly, then heating and curing in a mold to obtain the epoxy resin cured product.

Images