Green toughening treatment technology of bio-based bisphenol A epoxy resin

Abstract

The invention discloses a green toughening treatment technology of bio-based bisphenol A epoxy resin. A eugenol-based curing agent AEESN and bisphenol A diglycidyl (DGEBA) are cured, the molar ratio of epoxy groups to amino groups in the AEESN is 1: (1.0-1.5), uniform mixing is performed at the temperature of 20-50 DEG C, curing is performed at the temperature of 60-110 DEG C, and a polymer sample is prepared. The obtained polymer has good mechanical performance at normal temperature. The epoxy resin is subjected to different degrees of low-temperature toughening treatment, so that the impact resistance is increased from 6.1 KJ / m < 2 > to 54.0 KJ / m < 2 >.

Description

Technical Field

[0001] The invention relates to the field of polymer materials, and in particular to a green toughening treatment technology for bio-based bisphenol A epoxy resin. Background Art

[0002] Epoxy resin (EP) has outstanding mechanical strength and good chemical stability. It has been widely used in aerospace, coatings, and construction industries. As the application scope of epoxy resin continues to expand, the structure of epoxy resin is also constantly evolving. It is widely used in the fields of construction, automobiles, and aerospace, especially in electrical and electronic equipment including electronic appliances, 5G fields, integrated circuit chips and their packaging components. The demand for epoxy resin is increasing. It cannot be ignored that petroleum-based epoxy resin also has disadvantages such as biological toxicity and environmental unfriendliness. The rapid development of bio-based raw materials in recent years has provided a more environmentally friendly raw material library for the research of the resin industry, and opened up a new way to effectively overcome the biosafety issues of traditional petrochemical products.

[0003] In addition, due to the rigid skeleton of epoxy monomer and curing agent, epoxy resin is relatively brittle, and the impact strength of traditional DGEBA epoxy resin is basically maintained at 10KJ / m 2 So how to change these structures and improve their impact resistance is a challenging task. Generally, it is generally believed that epoxy resin monomers or curing agents with flexible chains and hyperbranched chains are conducive to topological toughening. At the same time, by increasing the curing temperature, the impact strength of epoxy resin can also be significantly improved. However, these modification strategies based on changing the chemical structure of raw materials are still limited to small-scale laboratory research. Therefore, there is a certain degree of environmental pollution and difficulty in technology promotion.

[0004] In order to effectively solve the problem of high brittleness, the present invention provides a bio-based bisphenol A epoxy resin polymer and a low-temperature green treatment toughening technology for the polymer, so that the impact strength at room temperature is 6.1±0.79KJ / m 2 After low-temperature toughening, the impact strength of the polymer increases by up to 10 times. Summary of the invention

[0005] Purpose of the invention: The technical problem to be solved by the present invention is to provide a method for preparing bio-based bisphenol A epoxy resin in view of the shortcomings of the prior art.

[0006] The technical problem that the present invention also aims to solve is to provide a green toughening treatment technology for bio-based bisphenol A epoxy resin.

[0007] In order to solve the first technical problem mentioned above, the present invention discloses a method for preparing a bio-based bisphenol A epoxy resin, wherein the structural units A and B are polymerized to form a new binary polymer. The structural units A and B are respectively:

[0008]

[0009] The binary polymer composed of A and B has a repeating structural unit shown in the following formula:

[0010]

[0011] Among them, m≥2, n≥2.

[0012] The molar ratio of the epoxy group of the epoxy monomer DGEBA to the amino group of the bio-based diamine curing agent AEESN is 1:1.0-1.5, preferably 1:1.0-1.2, preferably 1:1.2;

[0013] The mixing temperature is 20-60°C, preferably 50°C; the curing temperature is 60-110°C, preferably 60-100°C;

[0014] In order to solve the above-mentioned second technical problem, the present invention discloses a green toughening treatment method for bio-based bisphenol A epoxy resin, specifically, the polymer is frozen and stored at a freezing temperature of -20°C to -200°C, preferably -20°C, -78°C, and -196°C, and the freezing storage time is 14 days.

[0015] Beneficial effects: Compared with the prior art, the present invention has the following advantages:

[0016] (1) The curing agent used in the present invention is derived from biomass, which is cheap and readily available, has high biological added value, and is highly biosafe;

[0017] (2) The polymer raw materials provided by the present invention are all liquid at room temperature, easy to mix, have low polymerization temperature, and the preparation process is simple and the conditions are mild;

[0018] (3) The polymer has relatively excellent mechanical properties and has high impact strength after toughening treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, and the above and / or other advantages of the present invention will become more clear.

[0020] Figure 1 The infrared test curve of Example 1

[0021] Figure 2Results of impact resistance test of polymer DGEBA / AEESN after low-temperature toughening treatment at different temperatures DETAILED DESCRIPTION

[0022] The experimental methods described in the following examples are conventional methods unless otherwise specified; the reagents and materials described are commercially available unless otherwise specified.

[0023] Example 1 Preparation of DGEBA / AEESN Polymer

[0024] DGEBA (2.72 g, 8 mmol) and curing agent AEESN (1.72 g, 4.8 mmol) were weighed into a reaction bottle, mixed thoroughly at 50°C, and then injected into the mold prepared for the impact test sample. The temperature was slowly increased at a rate of 1.5°C / min under a nitrogen atmosphere, and the mixture was kept at 60°C for 2 h, 80°C for 1 h, and 100°C for 1 h, and then naturally cooled to room temperature to obtain the polymer DGEBA / AEESN.

[0025] Example 2 Low temperature toughening treatment

[0026] The polymer DGEBA / AEESN was stored at different degrees of low temperature for 14 days. Storage at -20℃ in a freezer; storage at -78℃ in dry ice; storage at -196℃ in liquid nitrogen. After the low temperature treatment, the sample was naturally restored to room temperature and stored for 14 days before testing.

[0027] The degree of polymerization of Example 1 was determined by infrared data, such as Figure 1 The infrared absorption peak of the stretching vibration of ethylene oxide in the epoxy monomer DGEBA is 860 cm -1 and 910cm -1 , while in the DGEBA / AEESN system these characteristic peaks disappeared, indicating that the epoxy resin was completely polymerized.

[0028] The mechanical properties of the untreated samples were tested, and the tensile strength was 55±14.2MPa and the bending strength was 104.8±12.9MPa. The impact resistance of the samples treated at room temperature and at different degrees of low temperature toughening was tested, and the results are as follows: Figure 2 Example 1 The impact strength of polymer DGEBA / AEESN at room temperature is 6.1±0.79 KJ / m 2 After being stored at -20℃ for two weeks, the impact resistance increased to 53.6±7.78KJ / m 2 , reaching 10.6 times. Even if the temperature is further reduced, the impact performance will not be significantly affected. After being stored at -78℃ for two weeks, the impact resistance test result is 54.01±4.81KJ / m 2After being stored at -196℃ for two weeks, the impact resistance test result was 46.6±11.6KJ / m 2 .

[0029] The present invention provides a green toughening treatment technology for bio-based bisphenol A epoxy resin. There are many methods and ways to implement the technical solution. The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention. All components not specified in this embodiment can be implemented by existing technologies.

Claims

1. A green toughening treatment technology for bio-based bisphenol A epoxy resin, characterized in that The structures of the bio-based curing agent AEESN and epoxy monomer DGEBA used are as follows: 。 2. A green toughening treatment technology for bio-based bisphenol A epoxy resin, characterized in that Structural units A and B are polymerized to form a new type of binary polymer. The structural units A and B are: The binary polymer composed of A and B has a repeating structural unit shown in the following formula: Among them, m≥2, n≥2.

3. A green toughening treatment technology for bio-based bisphenol A epoxy resin, characterized in that The substrate preparation method is to mix the bio-based curing agent AEESN with the epoxy monomer DGEBA and then perform injection molding and curing.

4. A green toughening treatment technology for bio-based bisphenol A epoxy resin according to claim 3, characterized in that The substrate preparation ratio is that the molar ratio of the epoxy group of the bio-based curing agent AEESN to the amino group is 1:1.0-1.5; the mixing temperature is 20-50°C; and the curing temperature is 60-110°C.

5. The green toughening treatment technology of bio-based bisphenol A epoxy resin according to claim 3, characterized in that The substrate has an average tensile strength of greater than 50 MPa, an average bending strength of greater than 100 MPa, and an average impact strength of greater than 6 KJ / m at room temperature. 2 .

6. The green toughening treatment technology of bio-based bisphenol A epoxy resin according to claim 3, characterized in that The substrate toughening method is low-temperature freezing treatment, wherein the low temperature range is 0°C to -200°C, and the test temperature is 25°C.

7. The green toughening treatment technology of bio-based bisphenol A epoxy resin according to claim 3, characterized in that After low-temperature green toughening treatment, the average impact strength of the substrate increases from 6.1KJ / m 2 Increased to 54.0KJ / m 2 .

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