Epoxy resin containing carbonate, its preparation method, epoxy cured product prepared therefrom, and method for degrading the epoxy cured product

Abstract

The present invention provides a carbonate-containing epoxy resin, a preparation method thereof, an epoxy cured product prepared therefrom, and a method for degrading the epoxy cured product. The carbonate-containing epoxy resin has a structure represented by formula (I) or formula (II), and each symbol in formula (I) and formula (II) is as defined in the specification. Thus, by reacting a carbonate group with an epoxy group, a carbonate-containing epoxy resin can be prepared, and the epoxy cured product obtained therefrom with a hardener has good thermal properties and mechanical properties and is biodegradable.

Description

Technical Field

[0001] The present invention relates to an epoxy resin, a preparation method thereof, an epoxy cured product prepared therefrom, and a method for degrading the epoxy cured product, and particularly to an epoxy resin containing a carbonate group, a preparation method thereof, an epoxy cured product prepared therefrom, and a method for degrading the epoxy cured product. Background Art

[0002] Currently, commercially available epoxy resins are mainly bisphenol A type bifunctional and novolac type polyfunctional. In synthesis, phenolic groups react with epichlorohydrin to form epoxy groups. Among them, the polyfunctional type is based on phenolic resin, and formaldehyde must be used in the preparation of phenolic resin. In addition to environmental protection issues, this method is also not conducive to the preparation of high molecular weight polyfunctional epoxy. The unique three-membered ring structure of epoxy resin can undergo various ring-opening reactions and can also be self-cured through catalysis. However, due to the difficulty of chain growth, the final homopolymer cured product has the disadvantage of poor performance. Therefore, most epoxy resins need to be copolymerized with epoxy resin hardeners to increase the crosslinking degree after curing. For current commercially available products, although the cured product has good physical properties, the generation of its crosslinked structure makes the product difficult to recycle, leading to an increasing issue of such waste.

[0003] Generally speaking, thermosetting materials have excellent thermal stability, chemical stability, and a high-density covalent bond crosslinked network structure, and are not easily dissolved and decomposed for recycling. If there are unstable bonds in the crosslinked network, the cured product has the potential to be degraded. In recent years, some studies have pointed out that the ester group has chemical decomposability and has been gradually applied to PET recycling. Therefore, if a similar concept can be introduced into epoxy resin, it is expected to have the opportunity to improve the degradability of waste and achieve the purpose of chemical recycling.

[0004] However, the preparation of ester groups is mainly formed by the reaction of carboxylic acid compounds with phenolic or alcohol compounds, and it is difficult to retain polyfunctional alcohol or phenolic groups for epoxidation during the preparation process. Therefore, it is restricted in the process of preparing derivative epoxy resins, resulting in no related products so far.

[0005] In view of this, how to synthesize an epoxy resin containing a carbonate group, and the cured product prepared therefrom has chemical degradability has become the goal of related industries. Summary of the Invention

[0006] An object of the present invention is to provide an epoxy resin containing a carbonate group and a preparation method thereof, which obtain a bifunctional or polyfunctional epoxy resin containing a carbonate group in its structure by reacting a polycarbonate or a carbonate compound with a molecule having an epoxy functional group under the catalysis of a catalyst. This epoxy resin can be directly used or can undergo subsequent reactions.

[0007] Another object of the present invention is to provide an epoxy cured product and a method for degrading the epoxy cured product, which cure a carbonate-containing epoxy resin to prepare the epoxy cured product, and the epoxy cured product can be degraded so that the product can be recycled and reused to reduce the environmental burden.

[0008] An embodiment of the present invention provides a carbonate-containing epoxy resin having a structure represented by Formula (I) or Formula (II):

[0009]

[0010]

[0011] Wherein, R 1 , R 2 , R 7 and R 8 are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, an alkoxy group having 1 to 6 carbon atoms, an aromatic group having 6 to 12 carbon atoms or a halogen atom, a and b are each independently an integer from 0 to 4, and e and f are each independently an integer from 0 to 5. X is a single bond, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, an oxygen atom, a sulfur atom, a sulfonyl group, a sulfinyl group, an acyl group, an aromatic group having 6 to 12 carbon atoms, a fluorene group, a structure represented by Formula (i) or Formula (ii):

[0012]

[0013]

[0014] Wherein, X 1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or an aromatic group having 6 to 12 carbon atoms. Y is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an isocyanurate, a structure represented by Formula (iii), Formula (iv) or Formula (v):

[0015]

[0016] Wherein, R 3 and R 4 are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, an alkoxy group having 1 to 6 carbon atoms, an aromatic group having 6 to 12 carbon atoms or a halogen atom, R 5 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, an alkoxy group having 1 to 6 carbon atoms, R 6is methylene, an alkyl group having 5 to 12 carbon atoms or a cycloalkyl group having 5 to 12 carbon atoms, c and d are each independently an integer from 0 to 4. Z is a single bond, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, an oxygen atom, a sulfur atom, a sulfonyl group, a sulfinyl group, an acyl group, an aromatic group having 6 to 12 carbon atoms, a fluorenyl group, a structure represented by formula (i) or formula (ii). n is the degree of polymerization, and 1 ≤ n ≤ 500, p is an integer from 1 to 11, q is an integer from 0 to 20, and r is an integer from 1 to 15.

[0017] Another embodiment of the present invention provides a method for preparing an epoxy resin containing a carbonate, comprising providing a structure containing an aromatic carbonate group, providing a structure containing an epoxy group, and performing a catalytic step. The structure containing an aromatic carbonate group has a structure represented by formula (A1) or formula (A2):

[0018]

[0019] The structure containing an epoxy group has a structure represented by formula (B):

[0020]

[0021] The catalytic step is to mix the structure containing an aromatic carbonate group with the structure containing an epoxy group, and then obtain an epoxy resin containing a carbonate under the catalysis of a catalyst, which has a structure represented by formula (I) or formula (II):

[0022]

[0023] wherein, R 1 , R 2 , R 7 and R 8 are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, an alkoxy group having 1 to 6 carbon atoms, an aromatic group having 6 to 12 carbon atoms or a halogen atom, a and b are each independently an integer from 0 to 4, e and f are each independently an integer from 0 to 5. X is a single bond, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, an oxygen atom, a sulfur atom, a sulfonyl group, a sulfinyl group, an acyl group, an aromatic group having 6 to 12 carbon atoms, a fluorenyl group, a structure represented by formula (i) or formula (ii):

[0024]

[0025] wherein, X 1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or an aromatic group having 6 to 12 carbon atoms. Y is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an isocyanurate, a structure represented by formula (iii), formula (iv) or formula (v):

[0026]

[0027] Among them, R 3 and R 4 are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, an alkoxy group having 1 to 6 carbon atoms, an aromatic group having 6 to 12 carbon atoms, or a halogen atom, and R 5 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, or an alkoxy group having 1 to 6 carbon atoms, and R 6 is a methylene group, an alkyl group having 5 to 12 carbon atoms, or a cycloalkyl group having 5 to 12 carbon atoms. c and d are each independently an integer from 0 to 4. Z is a single bond, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, an oxygen atom, a sulfur atom, a sulfonyl group, a sulfinyl group, an acyl group, an aromatic group having 6 to 12 carbon atoms, a fluorenyl group, a structure represented by formula (i) or formula (ii). n is the degree of polymerization, and 1 ≤ n ≤ 500, m is an integer from 2 to 12, p is an integer from 1 to 11, q is an integer from 0 to 20, and r is an integer from 1 to 15.

[0028] According to the method for preparing the epoxy resin containing carbonate described in the previous paragraph, the catalyst may be selected from the group consisting of 4-dimethylaminopyridine, imidazole, pyridine, 2-methylimidazole, 3-methylimidazole, and 2-ethyl-4-methylimidazole.

[0029] According to the method for preparing the epoxy resin containing carbonate described in the previous paragraph, the addition amount of the catalyst may be 0.1 wt% to 5 wt% of the content of the structure containing an epoxy group.

[0030] According to the method for preparing the epoxy resin containing carbonate described in the previous paragraph, the equivalent ratio of the epoxy group of the structure containing an epoxy group to the carbonate group of the structure containing an aromatic carbonate group may be 1.3 to 10.0.

[0031] Another embodiment of the present invention provides an epoxy cured product obtained by curing the aforementioned epoxy resin containing carbonate.

[0032] According to the epoxy cured product described in the previous paragraph, the curing reaction is completed by mixing the epoxy resin containing carbonate and a hardener and heating.

[0033] According to the epoxy cured product described in the previous paragraph, the hardener may be a phenolic resin, an amine compound, an active ester compound, a carboxylic acid compound, a cyanate ester compound, an isocyanate compound, an acid anhydride compound, a benzoxazine, a polycarbonate, or a mixture thereof.

[0034] According to the epoxy cured product described in the previous paragraph, the curing temperature of the curing reaction may be 180°C to 240°C.

[0035] Another embodiment of the present invention provides a method for degrading an epoxy cured product, comprising providing the aforementioned epoxy cured product and performing a degradation step, wherein the degradation step is to react an amine-containing compound with the epoxy cured product to degrade the epoxy cured product.

[0036] Thereby, the epoxy resin containing carbonate of the present invention is obtained by mixing a structure containing a carbonate group and a structure containing an epoxy group and catalyzing through a catalyst, and forms an epoxy cured product with excellent properties under the addition of a hardener. It can be degraded to enable recycling and reuse, meeting environmental protection benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] To make the above and other objects, features, advantages and embodiments of the present invention more obvious and understandable, the description of the drawings is as follows:

[0038] Figure 1 It is a flowchart showing the steps of a method for preparing an epoxy resin containing carbonate according to an embodiment of the present invention.

[0039] Figure 2 It is a flowchart showing the steps of a method for preparing an epoxy cured product according to another embodiment of the present invention.

[0040] Figure 3 It is a flowchart showing the steps of a method for degrading an epoxy cured product according to still another embodiment of the present invention.

[0041] Figure 4 It shows that of Example 1 1 1H-NMR spectrogram.

[0042] Figure 5 It shows that of Examples 2 to 4 1 1H-NMR spectrogram.

[0043] Figure 6 It shows that of Example 19 1 1H-NMR spectrogram.

[0044]

MAIN ELEMENT SYMBOL DESCRIPTION

[0045] 100: Method for preparing an epoxy resin containing carbonate

[0046] 200: Method for preparing an epoxy cured product

[0047] 300: Method for degrading an epoxy cured product

[0048] 110, 120, 130, 210, 220, 310, 320: Steps DETAILED DESCRIPTION OF THE EMBODIMENTS

[0049] The following will discuss various embodiments of the present invention in more detail. However, this embodiment can be an application of various inventive concepts and can be specifically implemented in various specific scopes. The specific embodiments are for illustrative purposes only and are not limited to the scope of the disclosure.

[0050] In the present invention, the compound structure is sometimes represented by a skeleton formula, which may omit carbon atoms, hydrogen atoms, and carbon-hydrogen bonds. If the functional group is clearly drawn in the structural formula, the drawn one shall prevail.

[0051] In the present invention, "carbonate-containing epoxy resin having a structure as shown in formula (I)" may be expressed as carbonate-containing epoxy resin shown in formula (I) or carbonate-containing epoxy resin (I) for the sake of brevity and fluency, and the representation of other compounds or groups may be deduced in the same manner.

[0052] <Carbonate-containing epoxy resin>

[0053] The present invention provides a carbonate-containing epoxy resin having a structure as shown in formula (I) or formula (II):

[0054]

[0055] Among them, R 1 , R 2 , R 7 and R 8 are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, an alkoxy group having 1 to 6 carbon atoms, an aromatic group having 6 to 12 carbon atoms, or a halogen atom, a and b are each independently an integer of 0 to 4, and e and f are each independently an integer of 0 to 5. X is a single bond, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, an oxygen atom, a sulfur atom, a sulfonyl group, a thionyl group, an acyl group, an aromatic group having 6 to 12 carbon atoms, a fluorene group, or a structure represented by formula (i) or formula (ii):

[0056]

[0057] Among them, X 1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an aromatic group having 6 to 12 carbon atoms. Y is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, isocyanurate, or a structure represented by formula (iii), formula (iv), or formula (v):

[0058]

[0059] Among them, R 3 and R4 Each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, an alkoxy group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, or a halogen atom, R 5 represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, or an alkoxy group having 1 to 6 carbon atoms, R 6 represents a methylene group, an alkyl group having 5 to 12 carbon atoms, or a cycloalkyl group having 5 to 12 carbon atoms, and c and d each independently represent an integer from 0 to 4. Z represents a single bond, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, an oxygen atom, a sulfur atom, a sulfonyl group, a sulfinyl group, an acyl group, an aryl group having 6 to 12 carbon atoms, a fluorenyl group, a structure represented by formula (i) or formula (ii). n represents the degree of polymerization, and 1 ≤ n ≤ 500, p is an integer from 1 to 11, q is an integer from 0 to 20, and r is an integer from 1 to 15.

[0060] Thereby, the epoxy resin containing a carbonate ester can be directly used or subjected to subsequent reactions due to the presence of the carbonate ester structure, and its degradability is improved by introducing the carbonate ester structure, achieving the purpose of chemical recycling.

[0061] <Preparation Method of Epoxy Resin Containing Carbonate Ester>

[0062] With reference to Figure 1 , which is a flowchart showing the steps of a preparation method 100 of an epoxy resin containing a carbonate ester according to an embodiment of the present invention. In Figure 1 , the preparation method 100 of the epoxy resin containing a carbonate ester includes step 110, step 120, and step 130.

[0063] Step 110 is to provide a structure containing an aromatic carbonate group, which has a structure represented by formula (A1) or formula (A2):

[0064]

[0065] Regarding R 1 , R 2 , R 7 , R 8 , X, a, b, e, f, and n, please refer to the above for their definitions and will not be elaborated here. Specifically, the structure containing an aromatic carbonate group can be, but is not limited to, a carbonate ester compound, a new carbonate plastic, or a polycarbonate recycling material, and the waste polycarbonate recycling material can be recycled from waste optical discs, which can reduce the environmental burden.

[0066] Step 120 is to provide a structure containing an epoxy group, which has a structure represented by formula (B):

[0067]

[0068] For the definition of Y, please refer to the above text and will not be elaborated here. m is an integer from 2 to 12.

[0069] Step 130 is a catalytic step. After mixing a structure containing an aromatic carbonate group and a structure containing an epoxy group, an epoxy resin containing a carbonate is obtained under the catalysis of a catalyst, which has a structure shown in formula (I) or formula (II):

[0070]

[0071]

[0072] Regarding R 1 、R 2 、R 7 、R 8 For the definitions of X, Y, a, b, e, f, p and n, please refer to the above text and will not be elaborated here. In addition, the equivalent ratio of the epoxy group of the aforementioned structure containing an epoxy group to the carbonate group of the structure containing an aromatic carbonate group can be 1.3 to 10.0, preferably 2.0 to 10.0.

[0073] Specifically, when the structure containing an aromatic carbonate group is the structure shown in formula (A1), the synthesized epoxy resin containing a carbonate is the structure shown in formula (I), and the reaction equation is shown in Table 1 below.

[0074]

[0075] In addition, when the structure containing an aromatic carbonate group is the structure shown in formula (A2), the synthesized epoxy resin containing a carbonate is the structure shown in formula (II), and the reaction equation is shown in Table 2 below.

[0076]

[0077] The aforementioned catalyst may contain lone pairs of electrons and is selected from the group consisting of 4-dimethylaminopyridine (DMAP), imidazole, pyridine, 2-methylimidazole, 3-methylimidazole, 2-ethyl-4-methylimidazole. Thus, the lone pairs of electrons of the catalyst can act with the epoxy groups in the structure containing an epoxy group, which is beneficial to initiate the subsequent curing reaction. Specifically, the addition amount of the aforementioned catalyst can be 0.1 wt% to 5 wt% of the content of the structure containing an epoxy group.

[0078] Specifically, the epoxy resin containing carbonate of the present invention utilizes the reaction between the carbonate group in the structure containing an aromatic carbonate group and the epoxy group in the structure containing an epoxy group. To prove the above concept, the present invention first conducts a model reaction through Synthesis Example 1, reacting diphenyl carbonate and bisphenol A diglycidyl ether (DGEBA) under the catalyst pyridine. Specifically, 1.00 g (9.3 mmol) of diphenyl carbonate (107.1 g / eq) and 3.51 g (18.6 mmol) of bisphenol A diglycidyl ether (188 g / eq) are placed in a 100 mL three-necked flask. After heating to 100 °C to confirm dissolution, 0.0175 g of pyridine catalyst is added and the reaction is carried out for 8 hours. Then, spectroscopic analysis is performed on the product obtained according to Synthesis Example 1. The data of the hydrogen spectrum: 1 H-NMR(CDCl 3 ), δ = 1.62(12H, H d ), 2.73(2H, H a ), 2.88(2H, H a’ ), 3.33(2H, H b ), 3.92(2H, H c ), 4.12(2H, H j ), 4.16(2H, H c’ ), 4.25(4H, H l , H l’ ), 4.35(2H, H j’ ), 5.36(2H, H k ), 6.80(8H, H h ), 6.88(4H, H n ), 6.95(2H, H p ), 7.12(8H, H g ), 7.27(4H, H o ); The data of the carbon spectrum: 13 C-NMR(CDCl 3 ), δ = 31.0(C d ), 41.6(C e ), 44.7(C a ), 50.2(C b ), 67.0(C l ), 68.5(C c ), 68.7(C j ), 74.6(C k ), 113.9(C h ), 114.6(Cn )、121.2 (°C) p )、127.7 (°C) g )、129.5 (°C) o )、143.7 (°C) f )、154.1 (°C) q )、156.2 (°C) i )、158.1 (°C) m ); Infrared spectrum data: FTIR (KBr, cm -1 ): ν = 1750 (C=O stretch of carbonyl group); And high-resolution mass spectrometry data: High resolution LC-MS (ESI-MS) m / z: [M + calcd. for C 55 H 58 O 11 894.40 g / mol; anal. 894.4050 g / mol, where the theoretical epoxy equivalent is 483.11 g / eq, and the actual epoxy equivalent is 476 g / eq. The reaction equation of Synthesis Example 1 is shown in Table 3 below, and it was found that the carbonate group can react with the epoxy group.

[0079]

[0080] <Epoxy cured product>

[0081] The present invention further provides an epoxy cured product, which is obtained by curing the aforementioned epoxy resin containing a carbonate group, and the aforementioned curing reaction is briefly described as follows, where Figure 2 Figure 38 shows a flowchart of the steps of a method 200 for preparing an epoxy cured product according to another embodiment of the present invention. In Figure 2 , the method 200 for preparing an epoxy cured product includes step 210 and step 220. Figure 2 In

[0082] Step 210 is a mixing step, which is to mix the carbonate-containing epoxy resin and the hardener to obtain a curable composition. Specifically, through Step 210, the carbonate-containing epoxy resin and the hardener can form a precursor solution containing the curable composition. In addition, the solvent used in the precursor solution is used to help the carbonate-containing epoxy resin and the hardener blend. Therefore, as long as it can dissolve the carbonate-containing epoxy resin and the hardener and does not react with the aforementioned two, it can be used as the solvent in Step 210. For the details of the carbonate-containing epoxy resin, please refer to the foregoing, which will not be elaborated herein. The hardener of the present invention can be, but is not limited to, phenolic resin, amine compound, active ester compound, carboxylic acid compound, cyanate ester compound, isocyanate compound, acid anhydride compound, benzoxazine, polycarbonate or a mixture thereof.

[0083] Step 220 is a curing step, which causes the carbonate-containing epoxy resin and the hardener to crosslink to form an epoxy cured product. Specifically, the above-mentioned curable composition can be directly ground into powder and heated to a molten state, or the above-mentioned precursor solution can be heated to cause the carbonate-containing epoxy resin and the hardener to crosslink. Moreover, the final curing temperature for heating can be 80°C to 240°C, preferably 180°C to 240°C, and the heating time can be 1 hour to 6 hours. More specifically, the aforementioned heating method can adopt a multi-stage heating and curing method. For example, it is heated at 180°C, 200°C, and 220°C for 2 hours each. The curing temperature and heating time for heating can be adjusted flexibly according to the types of the carbonate-containing epoxy resin and the hardener used, and the present invention is not limited thereto.

[0084] <Method for Degrading Epoxy Cured Product>

[0085] Please refer to Figure 3 , which is a flowchart showing the steps of a method 300 for degrading an epoxy cured product according to another embodiment of the present invention. In Figure 3 , the method 300 for degrading an epoxy cured product includes Step 310 and Step 320.

[0086] Step 310 is to provide the aforementioned epoxy cured product. Step 320 is a degradation step, which is to react an amine group-containing compound with the aforementioned epoxy cured product to degrade the epoxy cured product.

[0087] The following specific examples are further used to demonstrate the present invention, which is beneficial to those of ordinary skill in the technical field to which the present invention pertains, and can be fully utilized and practiced without excessive interpretation, and these examples should not be regarded as limiting the scope of the present invention, but are used to illustrate the materials and methods for implementing the present invention.

[0088] <Example / Comparative Example>

[0089] <Preparation of Epoxy Resin Containing Carbonate>

[0090] Example 1: Take 1.0 g of diphenyl carbonate and 3.51 g of bisphenol A epoxy resin (Changchun Artificial Resin product code BE188). After heating to 100 °C to confirm dissolution at a ratio of the two in an equivalent ratio of 1:2, then add 0.0175 g of pyridine and react for 8 hours to obtain the epoxy resin DPC-EP containing carbonate of Example 1, with an epoxy equivalent of 476 g / eq (the theoretical value is 483 g / eq).

[0091] Example 2: Take 1.50 g of polycarbonate and 4.44 g of bisphenol A epoxy resin (Changchun Artificial Resin product code BE188). After heating to 200 °C in a nitrogen environment at a ratio of the two in an equivalent ratio of 1:2 to make it in a molten state and then cooling to 100 °C, add 0.0133 g of pyridine (0.3 wt% of DGEBA), and react for 8 hours under mechanical stirring to obtain a dark coffee-colored viscous liquid. After cooling it to room temperature, obtain the epoxy resin WPC-EP2 containing carbonate of Example 2, with an epoxy equivalent of 485 g / eq (the theoretical value is 503 g / eq).

[0092] Example 3: Take 1.50 g of polycarbonate and 6.66 g of bisphenol A epoxy resin (Changchun Artificial Resin product code BE188). After heating to 200 °C in a nitrogen environment at a ratio of the two in an equivalent ratio of 1:3 to make it in a molten state and then cooling to 100 °C, add 0.0199 g of pyridine (0.3 wt% of DGEBA), and the remaining steps are the same as those in Example 2 to obtain the epoxy resin WPC-EP3 containing carbonate of Example 3, with an epoxy equivalent of 333 g / eq (the theoretical value is 345 g / eq).

[0093] Example 4: Take 1.50 g of polycarbonate and 8.88 g of bisphenol A epoxy resin (Changchun Artificial Resin product code BE188). After heating to 200 °C in a nitrogen environment at a ratio of the two in an equivalent ratio of 1:4 to make it in a molten state and then cooling to 100 °C, add 0.0266 g of pyridine (0.3 wt% of DGEBA), and the remaining steps are the same as those in Example 2 to obtain the epoxy resin WPC-EP4 containing carbonate of Example 4, with an epoxy equivalent of 285 g / eq (the theoretical value is 293 g / eq).

[0094] Perform 1 1H-NMR analysis on Examples 1 to 4 to confirm the structures of Examples 1 to 4. Please refer to Figure 4 and Figure 5 whereFigure 4 Show the 1 1H-NMR spectrum of Example 1, Figure 5 Show the 1 1H-NMR spectra of Examples 2 to 4. From Figure 4 and Figure 5 the results, it can be seen that the products of Examples 1 to 4 are all epoxy resins containing carbonate.

[0095] <Preparation of Epoxy Curing Agent>

[0096] For the epoxy resins containing carbonate synthesized in Examples 1 to 4, an equal equivalent of hardener was added, first ground into powder and then heated to 150 °C to be in a molten state. After stirring evenly, it was placed in an oven and heated to 160 °C for one hour, 180 °C for two hours, and 200 °C for two hours for curing; alternatively, the epoxy resins containing carbonate synthesized in Examples 1 to 4 and the hardener can be stirred until completely melted in a solution with a solid content of 20 wt%, poured into a mold and then cured to obtain the epoxy curing agents of Examples 5 to 16.

[0097] Specifically, the hardeners used in the present invention can be diaminodiphenylmethane (DDM), phenolic resin (PN), dicyandiamide (DICY), polycarbonate (PC), diphenyl ether tetracarboxylic dianhydride (ODPA), and phthalic anhydride (PAH). Taking Example 2 as an example, when different hardeners are selected, the prepared epoxy curing agents are shown in Table 4 below.

[0098]

[0099]

[0100] In addition, for the commercially available epoxy resins BE188 and BE501, an equal equivalent of hardener was added and the same curing steps as in Examples 5 to 16 were carried out to obtain the epoxy curing agents of Comparative Examples 1 to 4.

[0101] In detail, taking the hardener adding diaminodiphenylmethane as an example, adding an equal equivalent means that the epoxy equivalent is equal to the equivalent of active hydrogen, and taking the hardener adding polycarbonate as an example, adding an equal equivalent means that the epoxy equivalent is equal to the equivalent of carbonate group.

[0102] The epoxy resins and hardeners used in Examples 5 to 16 and Comparative Examples 1 to 4 are shown in Table 5 below.

[0103]

[0104]

[0105] <Thermal Property Evaluation>

[0106] The epoxy cured products of Examples 5 to 16 and Comparative Examples 1 to 4 were subjected to thermal property evaluation, which included glass transition temperature (T g ), 5% thermal weight loss temperature (T d5％ ), and char yield. The evaluation methods are as follows.

[0107] (I) Glass transition temperature: The storage modulus, the relationship between the Tan delta curve and temperature, and the glass transition temperature of the epoxy cured products prepared in Examples 5 to 16 and Comparative Examples 1 to 4 were measured using a Dynamic Mechanical Analyzer (DMA). Additionally, the glass transition temperature was measured using Thermo-Mechanical Analysis (TMA) under the condition of measuring at a heating rate of 5 °C / min.

[0108] (II) 5% thermal weight loss temperature and char yield: The 5% thermal weight loss temperature and the char yield at 800 °C of the samples were measured using Thermo-Gravimetric Analysis (TGA). The conditions for thermogravimetric analysis were to measure the weight change of the samples using a thermogravimetric analyzer under a nitrogen atmosphere at a heating rate of 20 °C / min. The 5% thermal weight loss temperature refers to the temperature at which the weight loss of the cured product sample reaches 5%. The higher the 5% thermal weight loss temperature, the better the thermal stability of the sample. The char yield at 800 °C refers to the residual weight ratio of the sample when the heating temperature reaches 800 °C. The higher the residual weight ratio at 800 °C, the better the thermal stability of the sample.

[0109] The measurement results of the glass transition temperature, storage modulus, thermal weight loss temperature, and char yield of Examples 5 to 16 and Comparative Examples 1 to 4 are shown in Table VI below.

[0110]

[0111] As can be seen from the results in Table VI, when DDM is used as the hardener, the glass transition temperature of the epoxy cured product obtained is higher than that of other hardeners. This is mainly because the functional number of the DDM hardener is greater than that of other hardeners, resulting in an increase in the crosslinking density and excellent thermal properties. However, the 5% thermal weight loss temperature is mainly related to the bonding after crosslinking. When PN is used as the hardener, the energy required to decompose the ether group is greater than that of the ester group and the amine group. Therefore, the epoxy cured product obtained has an excellent 5% thermal weight loss temperature. In addition, when PN and DDM are used as the hardeners, the main chain is mostly a benzene ring structure, which can have a closer molecule with the epoxy resin. Therefore, the char residue rate is relatively high. In addition, the epoxy resins containing carbonate in Examples 5 to 16 of the present invention can exhibit thermal properties similar to those of the commercially available epoxy resin cured products in Comparative Examples 1 to 4 after curing.

[0112] <Mechanical Property Evaluation>

[0113] Examples 5 to 16 and Comparative Examples 1 to 4 were evaluated for mechanical properties. The tensile strength and elongation at break were measured by a tensile test. The tensile test was measured at room temperature, and the test piece size was 5 cm long, 1 cm wide, and 0.04 to 0.10 mm thick. The measurement results of the tensile strength and elongation at break for Examples 5 to 16 and Comparative Examples 1 to 4 are shown in Table VII below.

[0114]

[0115] As can be seen from the results in Table VII, when PC is used as the hardener, its main chain is longer and the ester group of PC has a certain steric hindrance, which can cause higher molecular motion in the cured product, resulting in excellent tensile properties. In addition, the epoxy resins containing carbonate in Examples 5 to 16 of the present invention can exhibit mechanical properties similar to those of the commercially available epoxy resin cured products in Comparative Examples 1 to 4 after curing, and even generally superior to the results of Comparative Examples 1 to 4.

[0116] <Degraded Epoxy Cured Product>

[0117] Examples 17 to 19 are the results obtained from the degradation reactions of the epoxy cured products of Examples 8 to 10, respectively, while Comparative Examples 5 to 8 are the results obtained from the degradation reactions of the epoxy cured products of Comparative Examples 1 to 4, respectively. First, epoxy cured product films of Examples 8 to 10 and Comparative Examples 1 to 4 and 1-hexylamine were placed in a reactor. After the reaction was completed, 1-hexylamine was directly extracted using a vacuum concentrator, and Examples 17 to 19 and Comparative Examples 5 to 8 with the degradation completed were obtained. The types of epoxy cured products, reaction temperatures, reaction times, and residual weights required for Examples 17 to 19 and Comparative Examples 5 to 8 are listed in Table VIII below.

[0118]

[0119] Please refer to Figure 6 , which shows the 1 H-NMR spectrogram of Example 19. Specifically, Figure 6 (a) of 1 is the Figure 6 H-NMR spectrogram of the product after the aminolysis reaction of Example 10 and 1-hexylamine and evaporation of 1-hexylamine, while 1 (b) of

[0120] is the Figure 6 H-NMR spectrogram of the precipitate obtained by pouring the product after the aminolysis reaction of Example 10 and 1-hexylamine, evaporation of 1-hexylamine, and precipitation in methanol.

[0120] From Figure 6 the results, characteristic signals of 1,3-dihexylurea can be observed. The amine group signal (NH-CO-NH) of the urea structure is at 7.3 ppm, the methylene signals are at 2.9 ppm (H i ) and 1.2 - 1.4 ppm (H c-h ), and the methyl signal is at 0.8 ppm (H d ). Also, characteristic signals of phenoxy resin can be observed. The hydroxyl signal is at 5.3 ppm, the benzene ring signals are at 6.8 and 7.0 ppm, the methine and methylene signals are at 4.1 ppm (H b ) and 3.9 ppm (H a ) respectively, and the methyl signal is at 1.5 ppm (H c ). From Figure 6 the results and those in Table VIII, it can be shown that the epoxy cured product of Example 10 of the present invention has decomposability after reacting with an amino group-containing compound, and the residual weight of the epoxy cured product is 0%.

[0121] In addition, Example 8 and Example 9 also have partial degradability under the heating reaction of 1-hexylamine, with weight residues of 85% and 77% respectively. However, the epoxy cured products made from commercially available epoxy resins of Comparative Examples 1 to 4 showed no degradation even after the reaction time was extended to 24 hours under the same conditions, and the weight residues were all 100%. This proves that the synthesized epoxy resin containing carbonate has unique degradability and makes a significant contribution to the recycling and waste reduction of thermosetting materials.

[0122] In summary, the present invention obtains a bifunctional or polyfunctional epoxy resin containing carbonate groups through a simple one-step reaction. This preparation method can especially use recycled waste polycarbonate or carbonate compounds as raw materials, and has high atom efficiency, which helps to reduce the amount of polycarbonate waste. In addition, the epoxy resin containing carbonate of the present invention can react with a hardener to obtain an epoxy cured product with excellent properties, and has chemical degradability, which reduces the emission of thermosetting plastic waste and achieves the goal of sustainable utilization.

[0123] Although the present invention has been disclosed as above in the form of embodiments, it is not intended to limit the present invention. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be defined by the appended claims.

Claims

1. An epoxy resin containing a carbonate, characterized in that it has a structure shown in formula (I) or formula (II): Among them, R 1 , R 2 , R 7 and R 8 are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, an alkoxy group having 1 to 6 carbon atoms, an aromatic group having 6 to 12 carbon atoms or a halogen atom, a and b are each independently an integer from 0 to 4, and e and f are each independently an integer from 0 to 5; wherein, X is a single bond, an alkyl group with 1 to 12 carbon atoms, a cycloalkyl group with 3 to 12 carbon atoms, an oxygen atom, a sulfur atom, a sulfonyl group, a sulfinyl group, an acyl group, an aromatic group with 6 to 12 carbon atoms, a fluorenyl group, a structure shown in formula (i) or formula (ii): wherein, X 1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms; wherein, Y is an alkyl group with 1 to 12 carbon atoms, an alkoxy group with 1 to 12 carbon atoms, an isocyanurate, a structure shown in formula (iii), formula (iv) or formula (v): Among them, R 3 and R 4 are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, an alkoxy group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, or a halogen atom, and R 5 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, or an alkoxy group having 1 to 6 carbon atoms, and R 6 is a methylene group, an alkyl group having 5 to 12 carbon atoms, or a cycloalkyl group having 5 to 12 carbon atoms, and c and d are each independently an integer from 0 to 4; wherein, Z is a single bond, an alkyl group with 1 to 12 carbon atoms, a cycloalkyl group with 3 to 12 carbon atoms, an oxygen atom, a sulfur atom, a sulfonyl group, a sulfinyl group, an acyl group, an aromatic group with 6 to 12 carbon atoms, a fluorenyl group, the said structure shown in formula (i) or formula (ii); and wherein, n is the degree of polymerization, and 1 ≤ n ≤ 500, p is an integer from 1 to 11, q is an integer from 0 to 20 and r is an integer from 1 to 15.

2. A method for preparing an epoxy resin containing a carbonate, characterized in that it comprises: providing a structure containing an aromatic carbonate group, which has a structure shown in formula (A1) or formula (A2): providing a structure containing an epoxy group, which has a structure shown in formula (B): and performing a catalytic step, which is to mix the structure containing an aromatic carbonate group with the structure containing an epoxy group, and then obtain an epoxy resin containing a carbonate under the catalysis of a catalyst, which has a structure shown in formula (I) or formula (II): wherein, R 1 , R 2 , R 7 and R 8 are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, an alkoxy group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms or a halogen atom, a and b are each independently an integer from 0 to 4, and e and f are each independently an integer from 0 to 5; wherein, X is a single bond, an alkyl group with 1 to 12 carbon atoms, a cycloalkyl group with 3 to 12 carbon atoms, an oxygen atom, a sulfur atom, a sulfonyl group, a sulfinyl group, an acyl group, an aromatic group with 6 to 12 carbon atoms, a fluorenyl group, a structure shown in formula (i) or formula (ii): wherein, X 1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms; wherein, Y is an alkyl group with 1 to 12 carbon atoms, an alkoxy group with 1 to 12 carbon atoms, an isocyanurate, a structure shown in formula (iii), formula (iv) or formula (v): wherein, R 3 and R 4 are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, an alkoxy group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, or a halogen atom, and R 5 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, or an alkoxy group having 1 to 6 carbon atoms, and R 6 is a methylene group, an alkyl group having 5 to 12 carbon atoms, or a cycloalkyl group having 5 to 12 carbon atoms, and c and d are each independently an integer from 0 to 4; wherein, Z is a single bond, an alkyl group with 1 to 12 carbon atoms, a cycloalkyl group with 3 to 12 carbon atoms, an oxygen atom, a sulfur atom, a sulfonyl group, a sulfinyl group, an acyl group, an aromatic group with 6 to 12 carbon atoms, a fluorenyl group, the said structure shown in formula (i) or formula (ii); wherein, n is the degree of polymerization, and 1 ≤ n ≤ 500, m is an integer from 2 to 12, p is an integer from 1 to 11, q is an integer from 0 to 20 and r is an integer from 1 to 15.

3. The method for preparing an epoxy resin containing a carbonate according to claim 2, characterized in that the catalyst is selected from the group consisting of 4-dimethylaminopyridine, imidazole, pyridine, 2-methylimidazole, 3-methylimidazole, 2-ethyl-4-methylimidazole.

4. The method for preparing an epoxy resin containing a carbonate according to claim 3, characterized in that the addition amount of the catalyst is 0.1 weight percentage to 5 weight percentage of the content of the structure containing an epoxy group.

5. The method for preparing an epoxy resin containing a carbonate according to claim 2, characterized in that the equivalent ratio of the epoxy group of the structure containing an epoxy group to the carbonate group of the structure containing an aromatic carbonate group is 1.3 to 10.

0.

6. An epoxy cured product, characterized in that It is obtained by curing reaction of the epoxy resin containing carbonate as described in claim 1.

7. The epoxy cured product as described in claim 6, characterized in that, the curing reaction is completed by mixing the epoxy resin containing carbonate and a hardener and heating.

8. The epoxy cured product as described in claim 7, characterized in that, the hardener is a phenolic resin, an amine compound, an active ester compound, a carboxylic acid compound, a cyanate ester compound, an isocyanate compound, an acid anhydride compound, benzoxazine, a polycarbonate or a mixture thereof.

9. The epoxy cured product as described in claim 7, characterized in that, the curing temperature of the curing reaction is 180 °C to 240 °C.

10. A method for degrading an epoxy cured product, characterized in that, comprising: providing the epoxy cured product as described in claim 6; and performing a degradation step, which is to react a compound containing an amino group with the epoxy cured product to degrade the epoxy cured product.

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