High-toughness epoxy resin composition as well as preparation method and application thereof

Abstract

The invention relates to a high-toughness epoxy resin composition as well as a preparation method and application thereof. The high-toughness epoxy resin composition comprises resin A and a curing agent B, the resin A comprises the following components in parts by weight: 70-90 parts of epoxy resin; 2-10 parts of a polyether polymer A; 2 to 20 parts of a core-shell pre-dispersion liquid; 0.2 to 8 parts of an auxiliary agent; the curing agent B comprises the following components in parts by weight: 75-90 parts of an anhydride curing agent; 1-10 parts of a polyether polymer B; and 0.1-4 parts of a catalyst. The high-toughness epoxy resin composition is an anhydride curing system and has excellent cured product toughness, and a pressure vessel made of the high-toughness epoxy resin composition is excellent in performance (free of apparent cracks and good in transparency) and can be well applied to a high-pressure gaseous hydrogen storage pressure vessel.

Description

Technical Field

[0001] This invention relates to the field of polymer composite materials technology, and in particular to a high-toughness epoxy resin composition, its preparation method, and its application. Background Technology

[0002] Composite material pressure vessels possess advantages such as light weight, high specific strength, good fatigue resistance, and good corrosion resistance, and are gradually replacing heavy steel pressure vessels in numerous fields including automotive, fire fighting, medical, hydrogen storage, and oil and gas transportation. Filament winding is the main production process for composite material pressure vessels, offering advantages such as high fiber content, the ability to achieve equal strength structural designs, stable quality, and ease of automated production.

[0003] Epoxy resins are frequently used as matrix resins in filament winding processes due to their excellent adhesion, mechanical properties, and chemical stability. However, ordinary epoxy resins have limited toughness; anhydride-cured systems are brittle, while amine-cured systems have short pot lives and are unsuitable for long-term winding operations. Therefore, improving the toughness of epoxy resins through various methods has become a current research hotspot.

[0004] Currently, modifying epoxy resins with rubber elastomers is a common method. However, the addition of toughening agents such as rubber-modified toughening resins often leads to a significant decrease in resin strength and modulus. For example, the reaction of carboxylated nitrile rubber (CTBN) with epoxy resin can form a rubber phase in the epoxy resin matrix. These rubber phases can effectively absorb and disperse energy, but CTBN has a significant impact on the resin's strength and modulus. In addition, CTBN-modified epoxy has a high viscosity, which is unfavorable for the viscosity requirements of the winding process. Furthermore, pressure vessels made using this type of epoxy anhydride system are prone to surface cracking, fatigue, and poor burst performance.

[0005] Therefore, it is necessary to develop and provide an epoxy resin composition that, while ensuring good tensile strength and elastic modulus, also has excellent elongation at break and impact toughness, and at the same time, ensures good appearance when applied to pressure vessels. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a high-toughness epoxy resin composition, its preparation method, and its applications. The high-toughness epoxy resin composition is an anhydride curing system, exhibiting excellent cured product toughness. It can be well applied to high-pressure gaseous hydrogen storage pressure vessels, and the pressure vessels made from it exhibit excellent performance (no obvious cracks on the surface, good transparency).

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a high-toughness epoxy resin composition comprising resin A and curing agent B;

[0009] The resin A comprises the following components in parts by weight:

[0010] 70-90 parts epoxy resin;

[0011] Polyether polymer A: 2-10 parts;

[0012] 2-20 parts of core-shell predispersant;

[0013] 0.2-8 parts of auxiliary agent;

[0014] The curing agent B comprises the following components in parts by weight:

[0015] 75-90 parts of acid anhydride curing agent;

[0016] Polyether polymer B: 1-10 parts;

[0017] Catalyst 0.1-4 parts.

[0018] This invention designs and optimizes the components of an epoxy resin composition, ensuring that the cured composition possesses good tensile strength and elastic modulus, as well as excellent elongation at break and impact toughness. Simultaneously, the pressure vessel made from this composition exhibits no obvious cracks, good transparency, and does not affect the display of pressure vessel labels or QR code scanning, making it well-suited for high-pressure gaseous hydrogen storage vessels. This invention satisfies the requirements of high strength, high toughness, and a glass transition temperature (Tg) meeting national standards for gas cylinders in epoxy anhydride systems, while simultaneously ensuring a good appearance for the pressure vessel. It effectively solves the technical problems of pressure vessels made from conventional epoxy resin compositions, such as easy cracking in the circumferential and shoulder areas, and poor fatigue and burst performance.

[0019] In this invention, the polyether polymer A in resin A, the core-shell pre-dispersion liquid and the epoxy resin component, as well as the polyether polymer B and the acid anhydride curing agent component in curing agent B, can all be well dispersed and compounded. By introducing polyether polymer A and the core-shell pre-dispersion liquid into resin A and introducing polyether polymer B into curing agent B for specific combination, the synergistic effect of the three can be achieved. This improves the toughness of the obtained high-toughness epoxy resin composition after curing while ensuring good strength. Consequently, when the high-toughness epoxy resin composition is applied to pressure vessels, the pressure vessels can still maintain good mechanical and appearance properties under pressure deformation, and have excellent transparency.

[0020] In this invention, polyether polymer A contains a large number of hydroxyl groups and flexible segments. The hydroxyl groups participate in the curing reaction and crosslink to form a stable crosslinked network structure. The flexible segments ensure that the obtained high-toughness epoxy resin composition has strong toughness after curing. The core-shell particles in the core-shell pre-dispersion liquid and polyether polymer B ensure the strength and certain toughness of the obtained high-toughness epoxy resin composition after curing. During the curing process, the epoxy-repellent part of polyether polymer B separates into islands, which can play a good synergistic role with the islands of core-shell particles in the core-shell pre-dispersion liquid, reducing residual stress and preventing the propagation of tip cracks. Thus, when the obtained epoxy resin composition is applied to pressure vessels, the pressure vessels can maintain good strength while also obtaining excellent toughness and appearance properties. In addition, when polyether polymer B is added to curing agent B, a small amount of hydroxyl groups in the structure of polyether polymer B pre-react with the anhydride curing agent to obtain a modified anhydride curing agent that improves toughness. At the same time, it inhibits the deCO2 behavior during the mixed storage of anhydride and catalyst, which is beneficial to improving the storage stability of the obtained curing agent composition.

[0021] The epoxy resin in resin A of the present invention can be 70, 72, 74, 76, 78, 80, 82, 84, 86, 88 or 90 parts by weight; the polyether polymer A can be 2, 3, 4, 5, 6, 7, 8, 9 or 10 parts by weight; the core-shell predispersant can be 2, 3, 5, 8, 10, 12, 14, 16, 18 or 20 parts by weight; and the additives can be 0.2, 0.5, 1, 2, 3, 4, 5, 6, 7 or 8 parts by weight. Specific values ​​between the above-mentioned values ​​are not exhaustively listed here for space limitations and for the sake of brevity.

[0022] The curing agent B of the present invention can contain 75, 78, 80, 82, 84, 86, 88 or 90 parts by weight of anhydride curing agent, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 parts by weight of polyether polymer B, and 0.1, 0.3, 0.5, 0.8, 1, 2, 3 or 4 parts by weight of catalyst. Specific values ​​between the above values ​​are not exhaustively listed here for space limitations and for the sake of brevity.

[0023] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. The purpose and beneficial effects of the present invention can be better achieved and realized through the following preferred technical solutions.

[0024] As a preferred embodiment of the present invention, the epoxy resin includes any one or a combination of at least two of glycidyl ether epoxy resin, glycidyl ester epoxy resin, glycidyl amine epoxy resin, alicyclic epoxy resin, or aliphatic epoxy resin.

[0025] It should be noted that in this invention, there are no special limitations on the selection of glycidyl ether epoxy resins, glycidyl ester epoxy resins, glycidyl amine epoxy resins, alicyclic epoxy resins, and aliphatic epoxy resins. Commonly used glycidyl ether epoxy resins, glycidyl ester epoxy resins, glycidyl amine epoxy resins, alicyclic epoxy resins, and aliphatic epoxy resins in the art are all applicable.

[0026] For example, the epoxy resins include, but are not limited to, commercially available products: Nan Ya NPEL-127 epoxy resin, Phoenix 0164 epoxy resin, Zhenzhengfeng MF-3285 epoxy resin, Saidal 2021P epoxy resin, Zhenzhengfeng MF-4101 epoxy resin, Xinyuan XY812 or Xinyuan XY636, etc.

[0027] Preferably, the polyether polymer A is a polyether polyol A.

[0028] Preferably, the polyether polyol A includes any one or a combination of at least two of low molecular weight polyether polyols, medium molecular weight polyether polyols, or high molecular weight polyether polyols, and is preferably a low molecular weight polyether polyol.

[0029] Preferably, the polyether polyol A is a low molecular weight polyether polyol and / or a medium molecular weight polyether polyol, and more preferably a low molecular weight polyether polyol.

[0030] It should be noted that in the polyether polyol A of the present invention, low molecular weight polyether polyol refers to polyether polyol with a weight average molecular weight of less than 1000; medium molecular weight polyether polyol refers to polyether polyol with a weight average molecular weight of 1000-5000; and high molecular weight polyether polyol refers to polyether polyol with a weight average molecular weight of more than 5000.

[0031] As a preferred embodiment of the present invention, the weight of the core-shell pre-dispersion liquid is 5-10 parts, for example, 5 parts, 5.5 parts, 6 parts, 6.5 parts, 7 parts, 7.5 parts, 8 parts, 8.5 parts, 9 parts, 9.5 parts or 10 parts, as well as specific values ​​between the above-mentioned values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0032] This invention optimizes the weight percentage of the core-shell pre-dispersion liquid, allowing for further control of its mass ratio with other components. This ensures the strength and toughness of the cured high-toughness epoxy resin composition, resulting in pressure vessels with no apparent cracks and good transparency when applied. At lower weight percentages, the cured high-toughness epoxy resin composition exhibits poor toughness and slight surface cracks in the pressure vessel. Conversely, at higher weight percentages, the cured high-toughness epoxy resin composition suffers from reduced strength and decreased transparency, affecting product label display and QR code recognition.

[0033] As a preferred embodiment of the present invention, the core-shell predispersant comprises a rubber CSR predispersant dispersed with glycidyl ether epoxy resin and / or a rubber CSR predispersant dispersed with alicyclic epoxy resin.

[0034] Preferably, the effective content of the core-shell predispersant is 40-45%, for example, it can be 40%, 40.5%, 41%, 41.5%, 42%, 42.5%, 43%, 43.5%, 44%, 44.5%, or 45%, as well as specific values ​​between the above-mentioned values. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific values ​​included in the range.

[0035] The core-shell predispersant of the present invention includes, but is not limited to, commercially available products such as Arkema XT-100, Arkema XT-151, Noterta FD2135, Kaneyuki MX-553, or Kaneyuki MX-962, etc.

[0036] As a preferred embodiment of the present invention, the additives include wetting agents and / or defoamers.

[0037] Preferably, the additives are wetting agents and defoamers.

[0038] Preferably, the wetting agent includes any one or a combination of at least two of the following: organosilicon surfactants, polyether-modified polysiloxane wetting agents, phosphate ester wetting agents, or fluorocarbon surfactants.

[0039] It should be noted that in this invention, there are no special limitations on the selection of organosilicon surfactants, polyether-modified polysiloxane wetting agents, phosphate ester wetting agents, and fluorocarbon surfactants. Commonly used organosilicon surfactants, polyether-modified polysiloxane wetting agents, phosphate ester wetting agents, and fluorocarbon surfactants in the art are all applicable.

[0040] Preferably, the wetting agent is in the range of 0.1-5 parts by weight, for example, 0.1 parts, 0.5 parts, 1 part, 2 parts, 3 parts, 4 parts or 5 parts, and specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0041] Preferably, the defoamer includes any one or a combination of at least two of the following: silicone defoamer, polyether defoamer, alcohol defoamer, fatty acid defoamer, or ester defoamer.

[0042] It should be noted that in this invention, there are no special limitations on the selection of the types of defoamers, such as silicone defoamers, polyether defoamers, alcohol defoamers, fatty acid defoamers, and ester defoamers. Commonly used silicone defoamers, polyether defoamers, alcohol defoamers, fatty acid defoamers, and ester defoamers in the art are all applicable.

[0043] Preferably, the defoamer is in the range of 0.1-3 parts by weight, for example, 0.1 parts, 0.3 parts, 0.5 parts, 0.8 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts or 3 parts, and specific values ​​between the above-mentioned values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0044] Preferably, the anhydride curing agent includes any one or a combination of at least two of aliphatic anhydride curing agents, alicyclic anhydride curing agents, or aromatic anhydride curing agents.

[0045] It should be noted that in this invention, there are no special limitations on the selection of the aliphatic anhydride curing agent, alicyclic anhydride curing agent, or aromatic anhydride curing agent. Commonly used aliphatic anhydride curing agents, alicyclic anhydride curing agents, or aromatic anhydride curing agents in the art are all applicable. For example, aliphatic anhydride curing agents include oxalic anhydride, maleic anhydride, adipic anhydride, or sebacic anhydride, etc.; alicyclic anhydride curing agents include methyltetrahydrophthalic anhydride (MTHPA), tetrahydrophthalic anhydride (THPA), hexahydrophthalic anhydride (HHPA), methylcyclohexenetetracarboxylic dianhydride (MCTC), nadic anhydride (NA), or methylnadic anhydride (MNA), etc.; aromatic anhydride curing agents include terephthalic anhydride (TPA), isophthalic anhydride (IPA), pyromellitic dianhydride (PMDA), or phenyltrimeric anhydride (TMA), etc.

[0046] Preferably, the catalyst comprises any one or a combination of at least two of the following: imidazole catalysts, tertiary amine catalysts, metal complex catalysts, or salt catalysts.

[0047] Preferably, the imidazole catalyst comprises any one or a combination of at least two of 2-methylimidazole, 2-ethyl-4-methylimidazole, or 2-phenylimidazole.

[0048] Preferably, the tertiary amine catalyst includes any one or a combination of at least two of triethylamine, benzyldimethylamine, or 2,4,6-tris(dimethylaminomethyl)phenol.

[0049] Preferably, the metal complex catalyst comprises stannous octoate and / or dibutyltin dilaurate.

[0050] Preferably, the salt catalyst comprises any one or a combination of at least two of benzyltriphenylphosphine bromide, benzyltriethylammonium chloride, or triphenylphosphine.

[0051] Preferably, the polyether polymer B is a polyether polyol B.

[0052] Preferably, the polyether polyol B includes any one or a combination of at least two of low molecular weight polyether polyols, medium molecular weight polyether polyols, or high molecular weight polyether polyols.

[0053] Preferably, the polyether polyol B is a low molecular weight polyether polyol and / or a medium molecular weight polyether polyol, and more preferably a medium molecular weight polyether polyol.

[0054] It should be noted that in the polyether polyol B of the present invention, low molecular weight polyether polyol refers to polyether polyol with a weight average molecular weight of less than 1000; medium molecular weight polyether polyol refers to polyether polyol with a weight average molecular weight of 1000-5000; and high molecular weight polyether polyol refers to polyether polyol with a weight average molecular weight of more than 5000.

[0055] This invention further preferably uses a low molecular weight polyether polyol for polyether polymer A and a medium molecular weight polyether polyol for polyether polymer B, which allows for better compounding of the two with the core-shell predispersant and epoxy resin. This results in a high-toughness epoxy resin composition that, after curing, exhibits superior strength and toughness. Consequently, when this high-toughness epoxy resin composition is applied to pressure vessels, the pressure vessels can achieve excellent toughness while maintaining excellent appearance and transparency.

[0056] Preferably, the mass ratio of resin A to curing agent B in the high-toughness epoxy resin composition is 100:(70-100), wherein (70-100) can be 70, 75, 80, 85, 90, 95 or 100, and specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0057] In a second aspect, the present invention provides another method for preparing a high-toughness epoxy resin composition as described in the first aspect, the method comprising the following steps:

[0058] Preparation of Resin A: Epoxy resin, polyether polymer A, core-shell pre-dispersion and additives are mixed to obtain resin A;

[0059] Preparation of curing agent B: Mix the acid anhydride curing agent, catalyst and polyether polymer B to obtain curing agent B.

[0060] As a preferred technical solution of the present invention, in the preparation of resin A, the mixing includes first heating and mixing epoxy resin, polyether polymer A and core-shell predispersant, and then adding additives for secondary mixing.

[0061] Preferably, the heating and mixing temperature is 60-120℃, for example, it can be 60℃, 70℃, 80℃, 90℃, 100℃, 110℃ or 120℃, and specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0062] Preferably, the heating and mixing time is 2-3 hours, for example, 2 hours, 2.1 hours, 2.2 hours, 2.3 hours, 2.4 hours, 2.5 hours, 2.6 hours, 2.7 hours, 2.8 hours, 2.9 hours, or 3 hours, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific values ​​included in the range.

[0063] Preferably, the heating and mixing are carried out under stirring.

[0064] Preferably, the stirring speed is 300-500 rpm, for example, it can be 300 rpm, 320 rpm, 340 rpm, 360 rpm, 380 rpm, 400 rpm, 420 rpm, 440 rpm, 460 rpm, 480 rpm or 500 rpm, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0065] Preferably, the additive needs to be cooled before being added.

[0066] Preferably, the cooling process involves reducing the system temperature to 20-60°C, for example, 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, or 60°C, as well as specific values ​​between these values. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific values ​​included in the range.

[0067] Preferably, the secondary mixing time is 1-2 hours, for example, it can be 1 hour, 1.1 hours, 1.2 hours, 1.3 hours, 1.4 hours, 1.5 hours, 1.6 hours, 1.7 hours, 1.8 hours, 1.9 hours or 2 hours, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0068] Preferably, the secondary mixing is carried out under stirring.

[0069] Preferably, the stirring speed is 300-500 rpm, for example, it can be 300 rpm, 320 rpm, 340 rpm, 360 rpm, 380 rpm, 400 rpm, 420 rpm, 440 rpm, 460 rpm, 480 rpm or 500 rpm, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0070] Specifically, the method for preparing resin A includes the following steps:

[0071] (1) Put epoxy resin, polyether polymer A and core-shell predispersant into a container and stir at 60-120℃ and 300-500rpm for 2-3 hours until homogeneous;

[0072] (2) Cool the system temperature of step (1) to 20-60℃, add the additives, and stir at 300-500 rpm for 1-2 h to obtain the resin A.

[0073] As a preferred technical solution of the present invention, in the preparation of curing agent B, the mixing includes first heating and mixing the acid anhydride curing agent and the catalyst, and then adding the polyether polymer B for secondary mixing.

[0074] Preferably, the heating and mixing temperature is 50-80℃, for example, it can be 50℃, 55℃, 60℃, 65℃, 70℃, 75℃ or 80℃, and specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0075] Preferably, the heating and mixing time is 2-3 hours, for example, 2 hours, 2.1 hours, 2.2 hours, 2.3 hours, 2.4 hours, 2.5 hours, 2.6 hours, 2.7 hours, 2.8 hours, 2.9 hours, or 3 hours, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific values ​​included in the range.

[0076] Preferably, the heating and mixing are carried out under stirring.

[0077] Preferably, the stirring speed is 300-500 rpm, for example, it can be 300 rpm, 320 rpm, 340 rpm, 360 rpm, 380 rpm, 400 rpm, 420 rpm, 440 rpm, 460 rpm, 480 rpm or 500 rpm, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0078] Preferably, the temperature of the secondary mixing is 50-80℃, for example, it can be 50℃, 55℃, 60℃, 65℃, 70℃, 75℃ or 80℃, as well as specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0079] Preferably, the secondary mixing time is 1-2 hours, for example, it can be 1 hour, 1.1 hours, 1.2 hours, 1.3 hours, 1.4 hours, 1.5 hours, 1.6 hours, 1.7 hours, 1.8 hours, 1.9 hours or 2 hours, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0080] Preferably, the secondary mixing is carried out under stirring.

[0081] Preferably, the stirring speed is 300-500 rpm, for example, it can be 300 rpm, 320 rpm, 340 rpm, 360 rpm, 380 rpm, 400 rpm, 420 rpm, 440 rpm, 460 rpm, 480 rpm or 500 rpm, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0082] In this invention, the catalyst and polyether polymer B in curing agent B are added sequentially under heating conditions, which can effectively improve the toughness of the resulting epoxy resin composition.

[0083] Specifically, the preparation method of the curing agent B includes the following steps:

[0084] (1) Add the anhydride curing agent and catalyst into a container and stir at 50-80℃ and 300-500 rpm for 2-3 hours until homogeneous;

[0085] (2) Add polyether polymer B to the system in step (1) and stir at 50-80℃ and 300-500 rpm for 1-2 h to obtain the curing agent B.

[0086] Thirdly, the present invention provides the application of the high-toughness epoxy resin composition as described in the first aspect in winding processes and articles.

[0087] Preferably, the article comprises a high-pressure gaseous hydrogen storage pressure vessel.

[0088] Compared with the prior art, the present invention has at least the following beneficial effects:

[0089] (1) By designing and optimizing the components of the epoxy resin composition, the present invention can ensure that the epoxy resin composition has good strength and excellent toughness after curing, and the glass transition temperature far exceeds the national standard requirements (Tg is 105℃); at the same time, the pressure vessel made there are no obvious cracks on the surface, the surface transparency is good, and it does not affect the display of the pressure vessel label and QR code scanning, so it can be well applied to high pressure gaseous hydrogen storage pressure vessels.

[0090] (2) The high-toughness epoxy resin composition provided by the present invention has a cured Tg of 115-135℃, a tensile strength of 74.89-80.57 MPa, an elastic modulus of 2850-3077 MPa, an elongation at break of 7.54-11.21%, and an impact toughness of 62.68-83.11 KJ / m. 2 The pressure vessel has no obvious cracks on its surface and good transparency. Detailed Implementation

[0091] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0092] Unless otherwise specified, all reagents and raw materials used in the following examples and comparative examples are commercially available products. Some raw material information is shown in Table 1.

[0093] Table 1

[0094]

[0095] Examples 1-8 and Comparative Examples 1-3

[0096] Examples 1-8 and Comparative Examples 1-3 each provide a high-toughness epoxy resin composition comprising the components in parts by weight as shown in Table 2, where the unit is “parts”.

[0097] Table 2

[0098]

[0099] In this context, " / " indicates nothing.

[0100] Examples 1-8 and Comparative Examples 1-3 were prepared using the following method, specifically including the following steps:

[0101] Preparation of resin A:

[0102] (1) Put epoxy resin, polyether polymer A and core-shell predispersant into a container and stir at 90°C and 400 rpm for 2.5 h until homogeneous;

[0103] (2) Cool the system temperature of step (1) to 50°C, add wetting agent and defoamer, and stir at 400 rpm for 1.5 h to obtain resin A.

[0104] Preparation of curing agent B:

[0105] (1) Add the anhydride curing agent and catalyst into a container and stir at 65°C and 400 rpm for 2.5 h until homogeneous;

[0106] (2) Add polyether polymer B to the system in step (1) and stir at 65°C and 400 rpm for 1.5 h to obtain the curing agent B.

[0107] The high-toughness epoxy resin compositions obtained in Examples 1-8 and Comparative Examples 1-3 were subjected to performance tests, and the test methods / standards are as follows:

[0108] 1. Resin A and curing agent B in a high-toughness epoxy resin composition were mixed and cured (80℃×2 h + 110℃×1 h + 130℃×2 h) to obtain an epoxy resin material, which was then subjected to the following tests:

[0109] (1) Glass transition temperature (Tg): Tested according to GB / T 19466.2-2004;

[0110] (2) Tensile strength, elastic modulus, elongation at break and impact toughness: all were tested in accordance with GB / T 2567-2021.

[0111] II. After mixing resin A and curing agent B in a high-toughness epoxy resin composition to wet fibers, the mixture is wound and cured (80℃×2 h+110℃×1 h+130℃×2 h) to obtain a high-pressure gaseous hydrogen storage pressure vessel, which is then subjected to the following tests:

[0112] (1) Appearance of pressure vessel: Observe the appearance of the high-pressure gaseous hydrogen storage pressure vessel after self-tightening under 69 MPa pressure; no obvious cracks perpendicular to the fiber or cracks along the fiber direction indicate excellent; no obvious cracks along the fiber direction and a small number of slight cracks perpendicular to the fiber indicate good; obvious cracks perpendicular to the fiber and cracks along the fiber direction, and some cracks are relatively deep, indicate poor.

[0113] (2) Transparency: Observe the label display and QR code scanning results of the high-pressure gaseous hydrogen storage pressure vessel; clear and visible labels and easy-to-identify QR codes indicate excellent quality, while identifiable labels and QR codes indicate good quality.

[0114] The test results are shown in Table 3.

[0115] Table 3

[0116]

[0117] The test results show that:

[0118] (1) As can be seen from Examples 1 to 8, by designing and optimizing the components of the epoxy resin composition, the present invention enables the epoxy resin composition to have excellent toughness while ensuring strength after curing. It can be well applied to high-pressure gaseous hydrogen storage pressure vessels, with excellent appearance properties, no obvious cracks, and good transparency. Among them, the Tg of the obtained epoxy resin composition after curing is 115-135℃, the tensile strength is 74.89-80.57 MPa, the elastic modulus is 2850-3077 MPa, the elongation at break is 7.54-11.21%, and the impact toughness is 62.68-83.11 KJ / m. 2 .

[0119] (2) As can be seen from Examples 1-2 and Examples 6-8, compared with Examples 1-2 and Example 7, the weight fraction of the core-shell pre-dispersion liquid in Example 6 is lower, and the toughness of the high-toughness epoxy resin composition after curing is significantly worse, and slight cracks appear on the surface of the pressure vessel. In Example 8, the weight fraction of the core-shell pre-dispersion liquid is higher, and the strength of the high-toughness epoxy resin composition after curing is worse, and the apparent transparency of the pressure vessel is reduced. This shows that by optimizing the weight fraction of the core-shell pre-dispersion liquid, the present invention can further control its mass ratio with other components, thereby ensuring the strength and toughness of the obtained high-toughness epoxy resin composition after curing. As a result, when the high-toughness epoxy resin composition is applied to the pressure vessel, the pressure vessel can have no obvious cracks and good apparent transparency.

[0120] (3) By comparing Example 1 with Comparative Examples 1-3, it can be seen that the present invention can achieve the synergistic effect of polyether polymer A and core-shell pre-dispersion liquid in resin A and polyether polymer B in curing agent B by introducing them in a specific combination. This can improve the toughness of the obtained high-toughness epoxy resin composition after curing while ensuring good strength. As a result, the pressure vessel can still maintain good mechanical properties and appearance properties when it is under pressure deformation, and has excellent transparency. However, when any one of the three components is missing, the impact toughness of the obtained high-toughness epoxy resin composition after curing will decrease, and the appearance properties of the pressure vessel will deteriorate, with obvious cracks appearing.

[0121] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A high toughness epoxy resin composition, characterized by, The high-toughness epoxy resin composition comprises resin A and curing agent B; The resin A comprises components in the following weight proportions: Epoxy resin 70-90 parts; Polyether polymer A 2-10 parts; Core-shell pre-dispersion 2-20 parts; Auxiliary agent 0.2-8 parts; The curing agent B comprises components in the following weight proportions: Anhydride curing agent 75-90 parts; Polyether polymer B 1-10 parts; Catalyst 0.1-4 parts.

2. The high toughness epoxy resin composition according to claim 1, characterized in that, The epoxy resin comprises any one of glycidyl ether epoxy resin, glycidyl ester epoxy resin, glycidyl amine epoxy resin, alicyclic epoxy resin or aliphatic epoxy resin or a combination of at least two of them.

3. The high toughness epoxy resin composition according to claim 1 or 2, characterized in that, The polyether polymer A is polyether polyol A; Preferably, the polyether polyol A comprises any one of low molecular weight polyether polyol, medium molecular weight polyether polyol or high molecular weight polyether polyol or a combination of at least two of them; Preferably, the polyether polyol A is low molecular weight polyether polyol and / or medium molecular weight polyether polyol, and further preferably low molecular weight polyether polyol.

4. The high toughness epoxy resin composition according to any one of claims 1 to 3, characterized in that, The core-shell pre-dispersion is in a weight proportion of 5-10 parts; Preferably, the core-shell pre-dispersion comprises glycidyl ether epoxy resin dispersed rubber CSR pre-dispersion and / or alicyclic epoxy resin dispersed rubber CSR pre-dispersion; Preferably, the effective content of the core-shell pre-dispersion is 40-45%.

5. The high toughness epoxy resin composition according to any one of claims 1 to 4, characterized in that, The auxiliary agent comprises wetting agent and / or defoaming agent; Preferably, the auxiliary agent is wetting agent and defoaming agent; Preferably, the wetting agent is in a weight proportion of 0.1-5 parts; Preferably, the defoaming agent is in a weight proportion of 0.1-3 parts.

6. The high toughness epoxy resin composition according to any one of claims 1 to 5, characterized in that, The anhydride curing agent comprises any one of aliphatic anhydride curing agent, alicyclic anhydride curing agent or aromatic anhydride curing agent or a combination of at least two of them; Preferably, the catalyst comprises any one of imidazole catalyst, tertiary amine catalyst, metal complex catalyst or salt catalyst or a combination of at least two of them.

7. The high toughness epoxy resin composition according to any one of claims 1 to 6, characterized in that, The polyether polymer B is polyether polyol B; Preferably, the polyether polyol B comprises any one of low molecular weight polyether polyol, medium molecular weight polyether polyol or high molecular weight polyether polyol or a combination of at least two of them; Preferably, the polyether polyol B is low molecular weight polyether polyol and / or medium molecular weight polyether polyol, and further preferably medium molecular weight polyether polyol.

8. The high toughness epoxy resin composition according to any one of claims 1 to 7, characterized in that, The mass ratio of resin A to curing agent B in the high-toughness epoxy resin composition is 100:(70-100).

9. A process for the production of a high toughness epoxy resin composition as claimed in any one of claims 1 to 8, characterized in that, The preparation method comprises the following steps: Preparation of resin A: mixing epoxy resin, polyether polymer A, core-shell pre-dispersion and auxiliary agent to obtain resin A; Preparation of curing agent B: mixing anhydride curing agent, catalyst and polyether polymer B to obtain curing agent B.

10. Application of the high-toughness epoxy resin composition according to any one of claims 1-8 in winding process and products.

Images