Recyclable epoxy resin-based glass polymer solid adhesive

Abstract

The application discloses a recyclable epoxy resin glass high-molecular solid adhesive, and particularly discloses a method for preparing the recyclable glass high-molecular solid adhesive, which comprises the following steps: S1, adding diglycidyl ether and diacid or acid anhydride into a tetrafluoroethylene mold, and performing first heating treatment to obtain a mixture; S2, performing second heating treatment and cooling treatment on the mixture together with a catalyst to obtain a polymer; and S3, performing slicing treatment on the polymer to obtain the solid adhesive. The method does not need a solvent and is simple in operation.

Description

Technical Field

[0001] This invention relates to the field of polymer materials, specifically to a recyclable epoxy resin-based glass polymer solid adhesive and its preparation method. Background Technology

[0002] People's daily lives and production are inseparable from the use of various adhesives. Among them, epoxy resin adhesives are a classic type of adhesive. Due to their excellent mechanical properties, they are widely used in daily life and production. However, traditional epoxy resin adhesives often require a two-component reaction, making the final bonding effect extremely sensitive to reaction conditions. The ratio, temperature, time, and stirring all affect the final bonding effect. Secondly, the curing process often causes approximately 4% volume shrinkage, which can also generate internal stress to some extent, affecting the final bonding effect. Furthermore, the products often contain solvents and other volatile components that can have certain health effects; and the irreversible cross-linked structure of the final product makes it impossible to reshape or recycle, putting pressure on environmental protection. In contrast, solid adhesives are not affected by solvents, do not experience volume shrinkage during the curing process, and do not contain volatile components, while also being very easy to use. However, solid adhesives often suffer from poor bonding performance.

[0003] Therefore, there is an urgent need to design a high-performance, environmentally friendly, sustainable, low-cost, and recyclable solid adhesive. Summary of the Invention

[0004] This invention addresses the shortcomings of existing traditional adhesives by designing a high-performance solid adhesive that requires no solvent, can be repeatedly recycled, and is biodegradable, utilizing commercially available raw materials. This promotes sustainable and recyclable technological development and provides new ideas for designing and preparing novel recyclable and environmentally friendly materials.

[0005] In one aspect of the invention, a method for preparing a recyclable glass polymer solid adhesive is provided. According to an embodiment of the invention, the method includes:

[0006] S1: Diglycidyl ether and diacid or acid anhydride are added into a tetrafluoroethylene mold and subjected to a first heat treatment to obtain a mixture;

[0007] S2: The mixture is subjected to a second heating and cooling treatment with the catalyst to obtain a polymer;

[0008] S3: The polymer is sliced ​​to obtain the solid adhesive. The method according to embodiments of the present invention does not require solvents, is simple to operate, and the solid adhesive prepared by the method according to embodiments of the present invention has high performance and can be recycled and reused multiple times; it is biodegradable. The method according to embodiments of the present invention activates the exchange reaction (ester exchange reaction) of thermosetting polymer materials at high temperature. When the exchange reaction occurs for a sufficiently long time, the crosslinking network of the material changes without changing the crosslinking density, thereby realizing direct deformation processing and direct recycling of thermosetting polymer materials. The recyclable glass-like polymer solid adhesive prepared by the method according to embodiments of the present invention includes, but is not limited to, epoxy resins.

[0009] According to embodiments of the present invention, the above method may further include at least one of the following additional technical features:

[0010] According to embodiments of the present invention, the diglycidyl ether is bisphenol A diglycidyl ether, 1,4-butanediol diglycidyl ether, neopentyl glycol diglycidyl ether, or 1,4-dihydroxybiphenyl diglycidyl ether.

[0011] According to an embodiment of the present invention, the structure of the bisphenol A diglycidyl ether is as follows:

[0012]

[0013] According to embodiments of the present invention, the diacid is an aliphatic diacid, an aryl diacid, or a polyethylene glycol diacid.

[0014] According to embodiments of the present invention, the dicarboxylic acid is adipic acid, heptanoic acid, octanoic acid, azelaic acid, sebacic acid, dodecyl dicarboxylic acid, hexadecyl dicarboxylic acid, octadecyl dicarboxylic acid, hexadecyl dicarboxylic acid, octadecyl dicarboxylic acid, eicosyl dicarboxylic acid, docosyl dicarboxylic acid, terephthalic acid, phthalic acid, isophthalic acid, or polyethylene glycol dicarboxylic acid.

[0015] According to an embodiment of the present invention, the aliphatic diacid is n1 is selected from 1-22.

[0016] According to an embodiment of the present invention, the aryl diacid is terephthalic acid, phthalic acid or isophthalic acid.

[0017] According to an embodiment of the present invention, the polyethylene glycol diacid is The molecular weight range is 400-2000.

[0018] According to embodiments of the present invention, the acid anhydride is glutaric anhydride, adipic anhydride, or succinic anhydride.

[0019] According to an embodiment of the present invention, the molar ratio of the diglycidyl ether to the diacid or anhydride is 2:1 to 1:2.

[0020] According to an embodiment of the present invention, the polymer has the following structure:

[0021]

[0022] R is n1 is 1-22; or The polyethylene glycol diic acid The molecular weight range is 400-2000.

[0023] According to an embodiment of the present invention, the amount of catalyst used is 2-10 mol% relative to the amount of the diacid or anhydride. According to an embodiment of the present invention, this ratio means that if the amount of diacid is 100 mol, then the amount of catalyst is 2-10 mol. According to an embodiment of the present invention, the catalytic effect is high, and a material with good mechanical properties can be obtained.

[0024] According to embodiments of the present invention, the organic amine catalyst is tetramethylguanidine, 1,8-diazabicyclo[5.4.0]undec-7-ene or 1,5,7-triazabicyclo[4.4.0]decene-5-ene.

[0025] According to embodiments of the present invention, the organometallic salt catalyst is zinc acetate, aluminum acetate, lead acetate, zinc acetylacetone, iron acetylacetone, aluminum acetylacetone, or lead acetylacetone.

[0026] According to an embodiment of the present invention, the temperature of the first heat treatment is 80-200°C. The inventors have found that excessively low temperatures can cause the raw materials to fail to melt, resulting in an uneven reaction.

[0027] According to an embodiment of the present invention, the first heat treatment time is 5-20 minutes. The inventors have found that too short a time will result in the raw materials not being completely melted and mixed, leading to an uneven reaction.

[0028] According to an embodiment of the present invention, the temperature of the second heat treatment is 80-200°C.

[0029] According to an embodiment of the present invention, the second heat treatment time is 5-20 minutes. The inventors have found that too short a time will result in insufficient viscosity, making subsequent hot pressing difficult.

[0030] According to an embodiment of the present invention, the slicing process is carried out at a temperature of 80-200°C and a pressure of 2-10 MPa. The inventors have found that if the temperature or pressure is outside this range, the exchange reaction efficiency may not be fast enough, resulting in an excessively long heating time.

[0031] According to an embodiment of the present invention, the thickness of the slice obtained after the slicing process is 0.03–10 mm. The inventors have found that this thickness allows the product to be processed to a custom thickness, demonstrating excellent utilization efficiency.

[0032] In another aspect, the present invention also provides a method for preparing a recyclable glass polymer solid adhesive. According to an embodiment of the present invention, the method includes:

[0033] S1: Add bisphenol A diglycidyl ether and diacid or anhydride in a molar ratio of 2:1-1:2 into a tetrafluoroethylene mold, heat to melt and stir thoroughly to obtain a mixture;

[0034] S2: Add 2-10 mol% of 1,5,7-tripropylheptaoxytrimethylammonium salt relative to the amount of the diacid or anhydride to the mixture, continue heating and stirring for 5-20 minutes until the system gradually thickens and can be drawn into threads, then stop heating to obtain the polymer;

[0035] S3: The cooled polymer is hot-pressed into thin sheets of 0.03–10 mm at a temperature of 80–200 °C and a pressure of 2–10 MPa. The sheets are then cut to suitable sizes to obtain the solid adhesive. The method according to embodiments of the present invention does not require solvents, is simple to operate, and the solid adhesive prepared by the method according to embodiments of the present invention has high performance and can be recycled and degraded multiple times.

[0036] In another aspect, the present invention also provides a recyclable glass polymer solid adhesive. According to an embodiment of the invention, the solid adhesive is prepared by the method described above.

[0037] This invention has at least one of the following technical effects:

[0038] 1) The preparation method according to the embodiments of the present invention does not require the use of solvents, and is low in cost;

[0039] 2) The process parameters of the preparation method according to the embodiments of the present invention are easy to control;

[0040] 3) The preparation method according to the embodiments of the present invention is simple:

[0041] 4) The solid adhesive according to embodiments of the present invention is reusable;

[0042] 5) Degradation of solid adhesives according to embodiments of the present invention. Attached Figure Description

[0043] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0044] Figure 1 The infrared spectrum of Embodiment 1 according to the present invention;

[0045] Figure 2 This describes the bonding effect of Embodiment 1 of the present invention on various metals;

[0046] Figure 3 This is a comparison of the adhesive strength of Example 1 of the present invention after being placed in water for 48 hours;

[0047] Figure 4 The adhesive strength is required for recycling and reuse according to Example 1 of the present invention. Detailed Implementation

[0048] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0049] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0050] Example 1:

[0051] The recyclable epoxy resin-based glass polymer solid adhesive used in this embodiment is a material that can undergo an internal transesterification reaction, and is cured by bisphenol A diglycidyl ether and dodecyl diacid.

[0052] The specific preparation method of the recyclable epoxy resin-based glass polymer solid adhesive in this embodiment is as follows:

[0053] In a polytetrafluoroethylene mold, bisphenol A diglycidyl ether (340 mg, 1 mmol) and dodecyl diacid (230 mg, 1 mmol) were added and heated to melt at 160 °C. After stirring evenly, 1,5,7-triazabicyclo[4.4.0]dec-5-ene (14 mg) was added and heating and stirring continued for about 5 minutes. The resulting polymer solid was processed into a sheet with a thickness of about 0.25 mm using hot pressing technology at 180 °C, and finally the resulting solid adhesive was cut into the required shape using tools such as scissors.

[0054]

[0055] like Figure 1As shown: The structure was characterized using infrared spectroscopy to determine the functional groups in the polymer. Among them, 912 cm⁻¹ -1 No significant absorption was observed on either side, indicating that the free epoxy groups have been completely consumed by the reaction. The remaining absorptions originated from chemical bonds such as the benzene ring, OH, -CH2-, C=O, and COC.

[0056] Its bonding effect on various metals is shown in the figure. Figure 2 Where SS represents stainless steel, Fe represents iron, Al represents aluminum, and Cu represents copper, the roughness of the metals is r3.2. All metals were cleaned only with acetone and isopropanol before bonding, without any additional polishing process to increase the contact area.

[0057] The comparison of adhesive strength after 48 hours in water is shown below. Figure 3 After the sample was placed in tap water for 48 hours, the adhesive strength did not change significantly, indicating excellent water resistance.

[0058] Depend on Figure 4 It can be seen that the sample can be recycled three times and still retains about 82% of its original adhesive strength, indicating excellent reusability.

[0059] Example 2:

[0060] The specific recycling process for the recyclable epoxy resin-based glass polymer solid adhesive of Embodiment 1 of the present invention is as follows:

[0061] Collect recyclable epoxy resin-based glass polymer solid adhesive fragments with a knife or scissors, heat them to 80-200℃, apply hot pressing at 2-10MPa for 0.5-2 hours, cool to room temperature, and finally use scissors or other tools to cut the resulting solid adhesive into the required shape for reuse.

[0062] The above embodiments are illustrated using one example, but it should be understood that the present invention is not limited to the materials described above. Recyclable epoxy resin-based glass polymer solid adhesives that can undergo transesterification reactions can also be recycled.

[0063] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0064] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. Use of a polymer as a recyclable glass polymer-matrix solid adhesive, characterized in that, The polymer is prepared by the following method: S1: Diglycidyl ether and diacid or acid anhydride are added into a tetrafluoroethylene mold and subjected to a first heat treatment to obtain a mixture; S2: The mixture is subjected to a second heating and cooling treatment with the catalyst to obtain a polymer. When the polymer is used as a recyclable glass polymer solid adhesive, the polymer is sliced ​​to obtain the solid adhesive. Wherein, the diglycidyl ether is bisphenol A diglycidyl ether, 1,4-butanediol diglycidyl ether, neopentyl glycol diglycidyl ether or 1,4-dihydroxybiphenyl diglycidyl ether; The structure of the bisphenol A diglycidyl ether is as follows: ； The diacid is an aliphatic diacid, an aryl diacid, or a polyethylene glycol diacid; The aliphatic diacid is n1 is selected from 1-22; The aryl diacid is terephthalic acid, phthalic acid or isophthalic acid; The polyethylene glycol diacid is with a molecular weight range of 400-2000; The acid anhydride is glutaric anhydride, adipic anhydride, or succinic anhydride; The molar ratio of the diglycidyl ether to the diacid or anhydride is 2:1 to 1:2; The amount of the catalyst used relative to the amount of the diacid or anhydride is 2-10 mol% The catalyst is an organic amine catalyst or an organometal salt catalyst; The organic amine catalyst is tetramethylguanidine, 1,8-diazabicyclo[5.4.0]undec-7-ene or 1,5,7-triazabicyclo[4.4.0]decene-5-ene; The organometallic salt catalyst is zinc acetate, aluminum acetate, lead acetate, zinc acetylacetone, iron acetylacetone, aluminum acetylacetone, or lead acetylacetone.

2. Use according to claim 1, characterized in that, The structure of the polymer is R is , n1 is 1-22; or , polyethylene glycol diacid having a molecular weight range of 400-2000.

3. Use according to claim 1, characterized in that, The temperature of the first heat treatment is 80-200ºC; the time of the first heat treatment is 5-20 minutes.

4. Use according to claim 1, characterized in that, The temperature of the second heat treatment is 80-200ºC; the time of the second heat treatment is 5-20 minutes.

5. Use according to claim 1, characterized in that, The slicing process is carried out at a temperature of 80-200°C and a pressure of 2-10 MPa; the thickness of the slices obtained after the slicing process is 0.03-10 mm.

6. Use according to claim 1, characterized in that, The dicarboxylic acid is malonic acid, succinic acid, adipic acid, heptapic acid, octanoic acid, azelaic acid, sebacic acid, dodecyl diacid, hexadecyl diacid, octadecyl diacid, eicosyl diacid, and dodecyl diacid.

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