Adhesive composition, adhesive and use

Abstract

The present application relates to the technical field of adhesives, in particular to an adhesive composition, an adhesive and application, and a composite part. The adhesive composition comprises: an ionic liquid resin having a structure shown in formula I, a vinyl epoxy resin and a curing agent; wherein the curing agent is a free radical initiator; wherein in formula I, x is an integer selected from 1-10, y is an integer selected from 0-10, L ‑ is selected from anions. The adhesive prepared from the adhesive composition has good bonding force, can fill the gap between the metal sealing head and the plastic liner, has good low-temperature toughness, and further improves the sealing property of the plastic liner.

Description

Technical Field

[0001] This invention relates to the field of adhesive technology, specifically to an adhesive composition, an adhesive and its application, and a composite component. Background Technology

[0002] Plastic liner fabricated by injection molding typically consists of a metal end cap and an injection-molded part, which are then assembled and welded together. However, due to differences in the machining precision of the metal part and the precision of the plastic during processing, as well as the varying shrinkage rates of the metal and plastic during inflation and deflation, gaps of varying sizes often exist between the metal end cap and the injection-molded part during use. Some of these gaps can be filled by resin during subsequent winding, but a significant portion remains. Because ordinary winding resin is an epoxy system, it has poor toughness and low adhesion to both plastic and metal. During subsequent cycles, repeated thermal expansion and contraction, as well as deformation and compression of the liner, can easily cause it to detach from one of the phases.

[0003] To address the aforementioned issues, existing technologies generally employ two approaches for improvement. The first approach enhances the sealing effect by modifying the sealing structure, as exemplified by CN202121312277.X, CN201720862795.X, and CN2017109756818.3. However, these approaches suffer from complex structures and difficulties in processing. The second approach achieves sealing by improving the type of adhesive and its bonding method, as exemplified by CN202022505887.3. However, this approach has drawbacks, such as adhesive falling into the inner liner during later curing and affecting the sealing reliability of critical components.

[0004] To provide an effective way to improve the sealing performance between the metal end cap and the plastic inner liner, reduce hydrogen leakage, and have good fatigue tear resistance in view of the hydrogen filling and releasing characteristics, it is urgent to develop an adhesive that is easy to use, has good adhesion to both metals and plastics, and has good toughness. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned technical problems and provide an adhesive composition, an adhesive and its application, and a composite component. The adhesive has good bonding strength, can fill the gap between the metal end cap and the plastic liner, and has good low-temperature toughness, thereby improving the sealing performance of the plastic liner.

[0006] To achieve the above objectives, a first aspect of the present invention provides an adhesive composition comprising: an ionic liquid resin having the structure shown in Formula I, a vinyl epoxy resin, and a curing agent; wherein the curing agent is a free radical initiator;

[0007]

[0008] In Equation I, x is selected from integers from 1 to 10, y is selected from integers from 0 to 10, and L - Selected from anions.

[0009] A second aspect of the present invention provides an adhesive, said adhesive being prepared by reacting the adhesive composition provided in the first aspect;

[0010] The reaction conditions are as follows: temperature is 10-130℃, preferably 60-90℃; rotation speed is 100-1000rpm, preferably 300-800rpm; and time is 0.1-5h, preferably 0.1-2h.

[0011] The third aspect of the present invention provides the application of the adhesive provided in the second aspect in a plastic liner, preferably in a carbon fiber wound hydrogen storage cylinder with a plastic liner.

[0012] A fourth aspect of the present invention provides a composite component comprising an upper metal end cap and a lower gas cylinder liner, and an adhesive layer disposed between the metal end cap and the gas cylinder liner; wherein the adhesive layer is obtained by curing an adhesive provided in the second aspect.

[0013] Compared with the prior art, the present invention has the following advantages:

[0014] (1) The present invention uses ionic liquid resin and vinyl epoxy resin with the structure shown in Formula I as effective components of adhesive. Since the ionic liquid resin has double bonds, imidazole rings, amides and anions, under the premise of free radical initiator as curing agent, the ionic liquid resin and vinyl epoxy resin first undergo polymerization reaction and then epoxy reaction to obtain an adhesive with a dense cross-linked network structure. In this network structure, imidazole rings, hydroxyl groups and amides can generate a large number of hydrogen bonds with each other. In particular, specific anions can also participate in the formation of hydrogen bond network structure, thereby increasing the toughness and low temperature resistance of the adhesive. At the same time, due to the characteristics of ionic liquid resin, charge interaction can also greatly increase the toughness at low temperature.

[0015] (2) The adhesive provided by the present invention is applied to plastic liner, especially to carbon fiber wound hydrogen storage cylinders with plastic liner. The adhesive can quickly fill the gap between the metal end cap and the plastic liner, and improve the sealing performance of the liner for hydrogen. At the same time, the adhesive provided by the present invention has good toughness after curing, and will not break due to pressure deformation or gap changes in the liner during subsequent use. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a composite component provided by the present invention;

[0017] Figure 2This is a schematic diagram of the coating process of the adhesive provided by the present invention;

[0018] Figure 3 This is a schematic diagram of the formation of the adhesive layer provided by the present invention.

[0019] Explanation of reference numerals in the attached figures

[0020] 1. Metal end cap; 2. Base; 3. Gas cylinder liner; 4. Contact surface; 5. Scraper; 6. Flow transfer pump; 7. Adhesive; 8. Adhesive layer. Detailed Implementation

[0021] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0022] A first aspect of the present invention provides an adhesive composition comprising: an ionic liquid resin having the structure shown in Formula I, a vinyl epoxy resin, and a curing agent; wherein the curing agent is selected from free radical initiators;

[0023]

[0024] In Equation I, x is selected from integers from 1 to 10, y is selected from integers from 0 to 10, and L - Selected from anions.

[0025] In some embodiments of the present invention, preferably, the mass ratio of the ionic liquid resin to the vinyl epoxy resin is 1:0.05-0.5, for example, 1:0.05, 1:0.1, 1:0.2, 1:0.22, 1:0.25, 1:0.28, 1:0.3, 1:0.4, 1:0.5, and any value within any range of two such values, preferably 1:0.2-0.3. In the present invention, by controlling the mass ratio to satisfy the above range, the network structure of the adhesive is controlled, thereby controlling the toughness and low-temperature resistance of the adhesive.

[0026] In this invention, unless otherwise specified, the vinyl epoxy resin simultaneously has double bonds and epoxy groups. Preferably, the vinyl epoxy resin is selected from at least one of glycidyl methacrylate, glycidyl acrylate, and bisphenol A epoxy vinyl ester.

[0027] In some embodiments of the present invention, preferably, the mass ratio of the ionic liquid resin to the curing agent is 100:0.1-4, for example, 100:0.1, 100:0.5, 100:0.6, 100:0.7, 100:0.8, 100:0.9, 100:1, 100:1.5, 100:1.8, 100:2, 100:4, and any value within any range of any two values, preferably 100:0.1-2, more preferably 100:0.5-1. In the present invention, by controlling the amount of curing agent, the degree of reaction between the ionic liquid resin and the vinyl epoxy resin is controlled, thereby affecting the performance of the adhesive.

[0028] In some specific embodiments of the present invention, preferably, the curing agent is selected from at least one of sodium persulfate, potassium persulfate, azobisisobutyronitrile (AIBN), azobisisoheptanenitrile, dimethyl azobisisobutyrate, peroxybenzoic acid, peroxymethyl ethyl ketone, benzoyl peroxide, and cyclohexanone peroxide.

[0029] In this invention, the adhesive composition contains, in addition to the ionic liquid resin, vinyl epoxy resin and curing agent shown in Formula I, conventional resins, such as vinyl resins and / or epoxy resins.

[0030] In some specific embodiments of the present invention, preferably, the adhesive composition further includes an auxiliary resin; wherein the auxiliary resin is selected from at least one of 1-vinyl-3-methylimidazolium chloride, methyl methacrylate, bisphenol A epoxy resin and E51 type epoxy resin.

[0031] In some specific embodiments of the present invention, preferably, the mass ratio of the ionic liquid resin to the auxiliary resin is 100:0.1-2, for example, 100:0.1, 100:0.2, 100:0.3, 100:0.4, 100:0.5, 100:0.8, 100:1, 100:2, and any value within any range of any two values, preferably 100:0.1-0.5. In the present invention, the presence of the auxiliary resin is more beneficial for improving the elongation and bonding performance of the adhesive at low temperatures.

[0032] In a preferred embodiment of the present invention, the adhesive composition comprises the ionic liquid resin, the vinyl epoxy resin, and the curing agent.

[0033] In another preferred embodiment of the invention, the adhesive composition comprises the ionic liquid resin, vinyl epoxy resin, auxiliary resin and curing agent.

[0034] In some embodiments of the present invention, preferably, in formula I, L - Selected from NTf2 -Cl - I - ,Br - F - OH - Ac - CN - HS - , Preferred from NTf2 - Cl - OH - Ac - CN - HS - More preferably selected from NTf2 - Cl - .

[0035] In some embodiments of the present invention, in Formula I, x is selected from integers from 1 to 10, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, preferably integers from 1 to 5.

[0036] In some embodiments of the present invention, in Formula I, y is selected from integers from 0 to 10, for example, 0, 2, 3, 4, 5, 6, 7, 8, 9, 10, preferably integers from 0 to 5.

[0037] In this invention, the source of the ionic liquid resin having the structure of Formula I has a wide range of choices; it can be obtained commercially or prepared.

[0038] In some embodiments of the present invention, the ionic liquid resin is prepared by the following method:

[0039] (1) In a first solvent, the compound shown in Formula II and the compound shown in Formula III are subjected to a substitution reaction to obtain the compound shown in Formula IV;

[0040] (2) In an optional second solvent, the compound represented by Formula IV and an ion exchanger of general formula ML are subjected to an ion exchange reaction to obtain a structure having the structure represented by Formula I;

[0041]

[0042] Where x is selected from integers 1-10; y is selected from integers 0-10; L - The components are selected from anions, X is selected from Cl, I, Br, F; M is selected from alkali metals, specifically Li, Na, K.

[0043] In some embodiments of the present invention, in step (1), the conditions for the substitution reaction include: a temperature of 10-150°C and a time of 0.1-96 h; the molar ratio of the compound represented by Formula II to the compound represented by Formula III is 1:1-1.1, preferably 1:1-1.05.

[0044] In some embodiments of the present invention, in step (1), in the compound represented by formula II, y is selected from an integer from 0 to 10, preferably an integer from 0 to 5; in the compound represented by formula III, x is selected from an integer from 1 to 10, preferably an integer from 1 to 5; X is selected from Cl, I, Br, F, preferably Cl or Br.

[0045] In some embodiments of the present invention, in step (1), the first solvent is selected from organic solvents, preferably from THF, dioxane, acetonitrile, etc.

[0046] In some embodiments of the present invention, in step (2), the conditions for the ion exchange reaction include: a temperature of 10-150°C and a time of 0.1-96 h; the molar ratio of the compound represented by Formula IV to the ion exchanger is 1:1-1.1, preferably 1:1-1.05.

[0047] In some embodiments of the present invention, in step (2), the second solvent is selected from organic solvents, preferably from THF, dioxane, methanol, dichloromethane, etc.

[0048] A second aspect of the present invention provides an adhesive, said adhesive being prepared by reacting the adhesive composition provided in the first aspect;

[0049] The reaction conditions are as follows: temperature is 10-130℃, preferably 60-90℃; rotation speed is 100-1000rpm, preferably 300-800rpm; and time is 0.1-5h, preferably 0.1-2h.

[0050] The adhesive provided by this invention forms a cross-linked network structure with ionic liquid resin and vinyl epoxy resin. This network structure contains imidazole rings, amides, hydroxyl groups, and hydrogen bonds formed between them. In particular, specific anions can also participate in the formation of hydrogen bond network structure, thereby increasing the toughness and low-temperature resistance of the adhesive. At the same time, due to the characteristics of ionic liquid resin, charge interaction can also greatly increase the toughness at low temperatures.

[0051] In some embodiments of the present invention, preferably, the adhesive is obtained from the adhesive composition through a polymerization reaction and an epoxy reaction. In the present invention, the polymerization reaction involves the polymerization of an ionic liquid resin having the structure shown in Formula I and a vinyl epoxy resin under the action of a free radical initiator; the epoxy reaction involves the reaction of the amide in the ionic liquid resin with the epoxy group in the vinyl epoxy resin. That is, the adhesive composition provided by the present invention forms a dense cross-linked network structure through polymerization and epoxy reactions.

[0052] In some embodiments of the present invention, more preferably, the conditions for the polymerization reaction and the epoxide reaction are each independently: temperature of 10-130°C, preferably 60-90°C; rotation speed of 100-1000 rpm, preferably 300-800 rpm; and time of 0.1-5 h, preferably 0.1-2 h.

[0053] The third aspect of the present invention provides the application of the adhesive provided in the second aspect in a plastic liner, preferably in a carbon fiber wound hydrogen storage cylinder with a plastic liner.

[0054] A fourth aspect of the present invention provides a composite component comprising an upper metal end cap and a lower gas cylinder liner, and an adhesive layer disposed between the metal end cap and the gas cylinder liner.

[0055] The adhesive layer is obtained by curing the adhesive provided by the second aspect.

[0056] The adhesive provided by this invention has a moderate viscosity and is applied quickly and evenly to the underside of the metal end cap by smearing. When the metal end cap is bonded to the plastic inner liner, the adhesive is compressed and overflows from the gap between the metal end cap and the inner liner. It is cured at 10-130℃, preferably at 60-90℃ for rapid curing. The heat source can be removed after the adhesive is in a gel state, and the excess adhesive can be smoothed out with a scraper. After the inner liner is wrapped with carbon fiber and placed in the curing oven, the adhesive reacts and cures with the curing agent in the winding resin system at the curing temperature (110-130℃). Functionalized ionic liquid is used as the effective component of the adhesive, which has good compatibility and interactions such as coordination, hydrogen bonding, and charge, making it compatible with both nylon and metal. At the same time, the adhesive provided by this invention has good toughness after curing and will not break due to deformation of the inner liner or changes in gaps during subsequent use.

[0057] In some embodiments of the present invention, preferably, the curing conditions are: a temperature of 10-130°C, for example, 10°C, 20°C, 40°C, 60°C, 70°C, 80°C, 90°C, 100°C, 130°C, and any value within the range of any two values, preferably 60-90°C; and a time of 0.1-5h, for example, 0.1h, 0.5h, 1h, 1.5h, 2h, 5h, and any value within the range of any two values, preferably 0.1-2h.

[0058] The structural schematic diagram of the composite component provided by this invention is shown below. Figure 1 As shown, by Figure 1 It can be seen that the composite component consists of a metal end cap 1 on top, a gas cylinder liner 3 on the bottom, and an adhesive layer 8 between the two.

[0059] In some embodiments of the present invention, preferably, the thickness of the adhesive layer is 0.001-0.5 mm, for example, 0.001 mm, 0.005 mm, 0.01 mm, 0.05 mm, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.4 mm, 0.5 mm, and any value within the range of any two values, preferably 0.1-0.3 mm.

[0060] The adhesive layer prepared by the adhesive provided by the present invention has good elongation at break, bonding strength and low temperature resistance.

[0061] In some embodiments of the present invention, preferably, the adhesive layer has a bonding strength of ≥20MPa at 25°C, more preferably 20-30MPa, for example, 20MPa, 21MPa, 22MPa, 25MPa, 28MPa, 30MPa, and any value within the range of any two values.

[0062] In some embodiments of the present invention, preferably, the elongation at 25°C of the adhesive layer is ≥180%, preferably 180-250%, for example, 180%, 190%, 200%, 210%, 220%, 240%, 250%, and any value within a range of any two values.

[0063] In some embodiments of the present invention, preferably, the adhesive layer has a bonding strength of ≥20MPa at -40℃, more preferably 20-30MPa, for example, 20MPa, 21MPa, 22MPa, 25MPa, 28MPa, 30MPa, and any value within the range of any two values.

[0064] In some embodiments of the present invention, preferably, the elongation at -40°C of the adhesive layer is ≥40%, more preferably 40-60%, for example, 40%, 45%, 50%, 55%, 60%, and any value within a range of any two values.

[0065] In this invention, unless otherwise specified, the bonding strength at -40℃ and the bonding strength at 25℃ are measured using GB / T 39289-2020 Determination of Adhesive Bonding Strength for Metals and Plastics; the elongation at -40℃ and the elongation at 25℃ are measured using GB / T 528-2009 Tensile Stress-Strain Properties of Vulcanized Rubber or Thermoplastic Rubber.

[0066] In some embodiments of the present invention, preferably, the adhesive layer is prepared by the following method: applying the adhesive to the lower side of the metal end cap and pressing it into the inner liner of the gas cylinder, so that the adhesive fills the contact surface between the metal end cap and the inner liner of the gas cylinder and undergoes a curing reaction to obtain the adhesive layer.

[0067] One specific embodiment provided by the present invention is as follows: Figures 2-3 As shown, Figure 2 This is a schematic diagram of adhesive application. The metal end cap 1 is fixed on the base 2. The base 2 drives the metal end cap 1 to rotate slowly. The adhesive 7 is dripped onto the contact surface 4 (i.e., the contact surface 4 between the metal end cap 1 and the inner liner of the gas cylinder 3) through the flow delivery pump 6. The adhesive 7 is evenly applied to the contact surface 4 by the scraper 5. The scraper 5 and the contact surface 4 maintain a certain gap width to ensure the total amount of adhesive 4. At the same time, by setting the shape of the scraper 5, more adhesive is applied to the outer side than to the inner side. Figure 3 This is a schematic diagram of the formation of the adhesive layer. The metal end cap 1 coated with adhesive is pressed into the inner liner 3 of the gas cylinder through the pressing device 2, so that the adhesive and the inner liner 3 of the gas cylinder have good contact. During the pressing process, the outer adhesive can overflow through the contact surface 4 between the inner liner 3 of the gas cylinder and the metal end cap 1, forming an adhesive layer 8 to fill the gap between the two.

[0068] According to a particularly preferred embodiment of the present invention, an adhesive is prepared by reacting an adhesive composition, wherein the reaction conditions are: a temperature of 10-130°C, preferably 60-90°C; a rotation speed of 100-1000 rpm, preferably 300-800 rpm; and a reaction time of 0.1-5 h, preferably 0.1-2 h.

[0069] The adhesive composition comprises an ionic liquid resin having the structure shown in Formula I, a vinyl epoxy resin, and a curing agent; or, it comprises an ionic liquid resin having the structure shown in Formula I, a vinyl epoxy resin, an auxiliary resin, and a curing agent; wherein the auxiliary resin is selected from at least one of 1-vinyl-3-methylimidazolium chloride, methyl methacrylate, bisphenol A epoxy resin, and E51 type epoxy resin.

[0070] The curing agent is a free radical initiator;

[0071]

[0072] In Equation I, x is selected from integers from 1 to 5, y is selected from integers from 0 to 5, and L - Selected from NTf2 - Cl - OH - Ac - CN - HS - ;

[0073] The mass ratio of the ionic liquid resin to the curing agent is 100:0.1-4.

[0074] The mass ratio of the ionic liquid resin to the vinyl epoxy resin is 1:0.05-0.5.

[0075] The vinyl epoxy resin is selected from at least one of glycidyl methacrylate, glycidyl acrylate and bisphenol A epoxy vinyl ester;

[0076] The mass ratio of the ionic liquid resin to the auxiliary resin is 100:0.1-0.5.

[0077] The present invention will be described in detail below through embodiments.

[0078] The ionic liquid resins and epoxy resins used in the examples and comparative examples were all commercially available products.

[0079] Example 1

[0080] 100g of ionic liquid resin S1 (x=1, y=0, L selected from NTf2) having the structure shown in Formula I was used. - 20g of glycidyl acrylate and 0.8g of free radical initiator (AIBN) were reacted (at a temperature of 60℃, a rotation speed of 500rpm, and a time of 0.25h) to obtain adhesive W1.

[0081] Example 2

[0082] The method is the same as in Example 1, except that...

[0083] Replace the amount of the above free radical initiator (AIBN) with 1g;

[0084] Under the same conditions, adhesive W2 was obtained.

[0085] Example 3

[0086] The method is the same as in Example 1, except that...

[0087] Replace the amount of the above free radical initiator (AIBN) with 2g;

[0088] Under the same conditions, adhesive W3 was obtained.

[0089] Example 4

[0090] The method is the same as in Example 1, except that...

[0091] Replace the amount of the above free radical initiator (AIBN) with 0.1g;

[0092] Under the same conditions, adhesive W4 was obtained.

[0093] Example 5

[0094] The method is the same as in Example 1, except that...

[0095] Replace the amount of glycidyl acrylate with 50g;

[0096] Under the same conditions, adhesive W5 was obtained.

[0097] Example 6

[0098] The method is the same as in Example 1, except that...

[0099] Replace 0.8g of free radical initiator (AIBN) with 0.8g of free radical initiator (peroxybenzoic acid);

[0100] Under the same conditions, adhesive W6 was obtained.

[0101] Example 7

[0102] The method is the same as in Example 1, except that...

[0103] Replace 100g of ionic liquid resin S1 with 90g of ionic liquid resin S1 and 10g of methyl-3-methylimidazolium chloride.

[0104] Under the same conditions, adhesive W7 was obtained.

[0105] Example 8

[0106] The method is the same as in Example 1, except that...

[0107] Replace 20g of glycidyl acrylate with 10g of glycidyl acrylate and 10g of E51 epoxy resin.

[0108] Under the same conditions, adhesive W8 was obtained.

[0109] Examples 9-11

[0110] The method is the same as in Example 1, except that...

[0111] Change the type of ionic liquid resin, that is,

[0112] Replace ionic liquid resin S1 with ionic liquid resin S2 (x = 1, y = 0, L is selected from Cl) respectively. - ), ionic liquid resin S3 (x=1, y=2, L selected from NTf2) - ) and ionic liquid resin S4 (x = 6, y = 1, L selected from NTf2) - S1(x=1,y=0,L is selected from NTf2) - )

[0113] Under the same conditions, adhesives W9 and W11 were obtained respectively.

[0114] Comparative Example 1

[0115] The method is the same as in Example 1, except that...

[0116] The imidazole ring of ionic liquid resin S1 was replaced with a pyrrole ring to obtain ionic liquid resin DS1.

[0117] Under the same conditions, adhesive DW1 was obtained.

[0118] Comparative Example 2

[0119] The method is the same as in Example 1, except that...

[0120] The imidazole ring of ionic liquid resin S1 was replaced with a pyridine ring to obtain ionic liquid resin DS2.

[0121] Under the same conditions, adhesive DW2 was obtained.

[0122] Test case

[0123] The adhesives prepared in the above examples and comparative examples were respectively coated on the lower side of the metal end cap, and then contacted with the winding resin that overflowed through the metal end cap and cured (temperature 120°C; time 2h) to obtain an adhesive layer of 0.1 mm. The physical properties of the adhesive layers are listed in Table 1.

[0124] Table 1

[0125]

[0126] As can be seen from the results in Table 1, compared with Comparative Examples 1-2, the adhesive layers prepared by the adhesive provided by the present invention in Examples 1-11 have good elongation, bonding strength and low temperature resistance, especially with high elongation at -40℃ and bonding strength at -40℃.

[0127] Comparative Examples 1-2 show that because pyrrole and pyridine lack active hydrogen to initiate epoxy ring opening, their low degree of crosslinking results in high elongation at break and low strength.

[0128] Examples 1-4 regulate the elongation and bonding strength of the adhesive layer by adjusting the mass ratio of ionic liquid resin and curing agent. Compared with Example 1, Example 5 increases the amount of vinyl epoxy resin, resulting in a high degree of crosslinking of the adhesive, which leads to high bonding strength of the adhesive layer, but low elongation at break.

[0129] Compared to Example 1, Examples 7-8 respectively added vinyl resin and epoxy resin to regulate the degree of crosslinking of the adhesive, thereby affecting the performance of the adhesive layer.

[0130] Compared to Example 1, Examples 9-11 improved upon Example 1 by controlling the composition of the ionic liquid resin, especially the type of anion, NTF2. - Compared to Cl - It has better performance because it has more hydrogen bond acceptors, and the increased chain length is conducive to improving overall strength.

[0131] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. An adhesive composition, characterized in that, The adhesive composition comprises: an ionic liquid resin having the structure shown in Formula I, a vinyl epoxy resin, and a curing agent; wherein the curing agent is a free radical initiator; In Equation I, x is selected from integers from 1 to 10, y is selected from integers from 0 to 10, and L - Selected from anions.

2. The adhesive composition according to claim 1, wherein, The mass ratio of the ionic liquid resin to the vinyl epoxy resin is 1:0.05-0.5, preferably 1:0.2-0.

3.

3. The adhesive composition according to claim 1 or 2, wherein, The vinyl epoxy resin is selected from at least one of glycidyl methacrylate, glycidyl acrylate, and bisphenol A epoxy vinyl ester.

4. The adhesive composition according to any one of claims 1-3, wherein, The mass ratio of the ionic liquid resin to the curing agent is 100:0.1-4, preferably 100:0.1-2, and more preferably 100:0.5-1; Preferably, the curing agent is selected from at least one of sodium persulfate, potassium persulfate, azobisisobutyronitrile, azobisisoheptanenitrile, dimethyl azobisisobutyrate, peroxybenzoic acid, peroxymethyl ethyl ketone, benzoyl peroxide, and cyclohexanone peroxide.

5. The adhesive composition according to any one of claims 1-4, wherein, The adhesive composition further includes auxiliary resins; The auxiliary resin is selected from at least one of 1-vinyl-3-methylimidazolium chloride, methyl methacrylate, bisphenol A epoxy resin and E51 type epoxy resin; Preferably, the mass ratio of the ionic liquid resin to the auxiliary resin is 100:0.1-2, more preferably 100:0.1-0.5; More preferably, the adhesive composition comprises the ionic liquid resin, the vinyl epoxy resin, and the curing agent; or, the adhesive composition comprises the ionic liquid resin, the vinyl epoxy resin, the auxiliary resin, and the curing agent.

6. The adhesive composition according to any one of claims 1-5, wherein, In formula I, L - Selected from NTf2 - Cl - I - ,Br - F - OH - Ac - CN - HS - , Preferably, L - Selected from NTf2 - Cl - OH - Ac - CN - HS - ; More preferably, L - Selected from NTf2 - Cl - ; Preferably, x is selected from integers from 1 to 5, and y is selected from integers from 0 to 5.

7. An adhesive, characterized in that, The adhesive is prepared by reaction from the adhesive composition according to any one of claims 1-6; The reaction conditions are as follows: temperature is 10-130℃, preferably 60-90℃; rotation speed is 100-1000rpm, preferably 300-800rpm; and time is 0.1-5h, preferably 0.1-2h.

8. The application of the adhesive of claim 7 in a plastic liner, preferably in a carbon fiber wound hydrogen storage cylinder with a plastic liner.

9. A composite component, characterized in that, The composite component includes a metal end cap disposed on the top and a gas cylinder liner disposed on the bottom, as well as an adhesive layer disposed between the metal end cap and the gas cylinder liner; The adhesive layer is obtained by curing the adhesive described in claim 7.

10. The composite component according to claim 9, wherein, The curing conditions are: temperature of 10-130℃, preferably 60-90℃; time of 0.1-5h, preferably 0.1-2h. Preferably, the adhesive layer has a bonding strength of ≥20MPa at 25°C, more preferably 20-30MPa; and an elongation of ≥180% at 25°C, more preferably 180-250%. Preferably, the adhesive layer has a bonding strength of ≥20MPa at -40℃, more preferably 20-30MPa; and an elongation of ≥40% at -40℃, more preferably 40-60%. Preferably, the adhesive layer is prepared by the following method: applying the adhesive to the lower side of the metal end cap and pressing it into the inner liner of the gas cylinder, so that the adhesive fills the contact surface between the metal end cap and the inner liner of the gas cylinder and is cured to obtain the adhesive layer.

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