Reaction type flame retardant oxazolinyl benzene melamine and preparation method thereof

Abstract

The invention relates to a reactive flame retardant oxazolinyl benzene melamine and a preparation method thereof, the oxazolinyl benzene melamine is synthesized and prepared by adopting isophthalonitrile, dicyandiamide and ethanolamine as raw materials through a two-step method, the raw material molar ratio of the isophthalonitrile to the dicyandiamide to a catalyst is 1: (1-4): (0.01-0.5), and the reaction type flame retardant oxazolinyl benzene melamine is prepared through a two-step method. The raw material molar ratio of the intermediate product 2-cyanobenzene melamine to the ethanolamine to the catalyst is 1: (1-4): (0.01-0.5). When the oxazolinyl benzene melamine prepared by the preparation method disclosed by the invention is used for retarding flame of polyester and nylon, the compatibility of a flame retardant and a polymer resin matrix is improved, and the addition amount of the flame retardant is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of reactive flame retardant preparation, in particular to a reactive flame retardant oxazoline benzocyanate melamine and a preparation method thereof. Background Art

[0002] Flame retardants are special substances that enhance the fire resistance of polymer materials. By adding flame retardants to materials and changing some of the characteristics of the materials themselves, it is possible to effectively prevent combustion or slow down the spread of fire. There are many types of flame retardants. From the perspective of chemical composition, they can be divided into inorganic and organic types.

[0003] Among them, organic flame retardants are divided into organophosphorus flame retardants, halogen flame retardants, nitrogen flame retardants, etc. Nitrogen flame retardants are further divided into additive nitrogen flame retardants and reactive nitrogen flame retardants. Nitrogen flame retardants have been favored in recent years due to their advantages such as halogen-free, low toxicity, low smoke, heat and light stability, and good flame retardant efficiency.

[0004] The triazine ring is an effective component of a common nitrogen-based flame retardant, and the benzene ring is beneficial to increasing the high-temperature carbon residue rate of the substance. The 2-oxazoline group has a high reactivity. According to reports, when the compound containing the oxazoline group is ring-opened in the range of 220-240°C, it can react with functional groups containing active hydrogen such as carboxyl, amine, and amide within 3-5 minutes, and can be used as a chain extender and tackifier for polyester and nylon compounds.

[0005] At present, there is no research on the market on nitrogen-based reactive flame retardants that introduce oxazoline groups into nitrogen-containing triazine ring flame retardants to modify nitrogen-containing reactive flame retardants in order to improve the flame retardant properties of polyester, nylon and other products. Summary of the invention

[0006] The present invention aims to solve the shortcomings existing in the background technology and provides a reactive flame retardant oxazoline benzocyanuramine and a preparation method thereof. When flame retardant polyester and nylon, the flame retardant molecules can be introduced into the polymer molecular structure through the reaction of the oxazoline group with the terminal carboxyl group and the terminal amine group of the polyester and nylon compounds, thereby improving the compatibility of the flame retardant with the polymer resin matrix and further reducing the amount of the flame retardant added.

[0007] To achieve the above object, the present invention provides the following technical solutions: The present invention provides a reactive flame retardant oxazoline benzocyanate melamine, which is prepared from raw materials including isophthalonitrile, dicyandiamide and ethanolamine, and has a chemical structural formula of: .

[0008] At the same time, the present invention also provides a method for preparing a reactive flame retardant oxazoline benzocyanate melamine, which is prepared and synthesized by a two-step method, specifically comprising the following steps: (1) adding a formulated amount of isophthalonitrile into a reaction kettle, and then sequentially adding a solvent, dicyandiamide and a catalyst, stirring and heating under reflux; (2) After the reaction is completed, centrifuge, wash the precipitate, and centrifuge to obtain 2-cyanophenyl melamine; (3) Add 2-cyanophenyl melamine into a reaction kettle, and then add a solvent, ethanolamine and a catalyst in sequence, and stir and heat under reflux; (4) after the reaction is completed, the solvent is distilled off under reduced pressure, washed, and centrifuged to obtain the oxazoline benzocyanate melamine product; (5) The solidified product after centrifugation is sent to a dryer for drying, and the dried product is sent to a crusher for crushing into powder, thereby obtaining a finished product of reactive flame retardant oxazoline-based benzocyanuric melamine.

[0009] Furthermore, the solvent in step (1) is n-butanol, and the solvent in step (3) is xylene.

[0010] Furthermore, the isophthalonitrile, dicyandiamide, ethanolamine, n-butanol and xylene are all of industrial grade. Furthermore, the catalysts in step (1) and step (3) are one or more of zinc chloride, cupric chloride, cobalt nitrate, copper sulfate, zinc acetate, copper acetate potassium hydroxide, sodium hydroxide, potassium n-butoxide, and sodium ethoxide. Furthermore, the two-step synthesis process is as follows: (1) isophthalonitrile, dicyandiamide and a catalyst are mixed in a raw material molar ratio of 1:(1-4):(0.01-0.5) to prepare 2-cyanobenzoguanamine, and the reaction formula is as follows: ; (2) 2-cyanobenzoguanamine, ethanolamine and a catalyst are mixed in a raw material molar ratio of 1:(1-4):(0.01-0.5) to prepare oxazolinylbenzoguanamine, and the reaction formula is as follows: .

[0011] Furthermore, in step (1), the reaction temperature in the reactor is 117° C. and the pressure is 0.1-0.2 Mpa. Furthermore, the reaction temperature in the reactor in step (3) is 125° C., the pressure is 0.1-0.2 Mpa, and the reduced pressure distillation pressure is 0.01 Mpa.

[0012] Furthermore, the drying temperature and the corresponding drying time in step (5) are as follows: when the drying temperature is 60° C., the corresponding drying time is 2.0 hours.

[0013] Furthermore, the drying temperature and the corresponding drying time in step (5) are as follows: when the drying temperature is 65° C., the corresponding drying time is 1.75 hours.

[0014] Furthermore, the drying temperature and the corresponding drying time in step (5) are as follows: when the drying temperature is 70° C., the corresponding drying time is 1.5 hours. Furthermore, in step (2) and step (4), pure water is used for washing three times.

[0015] Furthermore, the molar yield of the 2-cyanophenyl melamine product in step (2) is not less than 99%, and the purity is not less than 99.6%.

[0016] Furthermore, the molar yield of the oxazoline benzocyanate melamine in step (4) is not less than 85%, and the purity is 99.5%.

[0017] Beneficial effects of the present invention: (1) The present invention provides a reactive flame retardant oxazoline benzocyanate melamine, which is a novel nitrogen-based reactive flame retardant. When the flame retardant synthesized by the present invention is used to flame retard polyester and nylon, the flame retardant molecules can be introduced into the polymer molecular structure through the reaction of the oxazoline group with the terminal carboxyl group and the terminal amine group of the polyester and nylon compounds, thereby improving the compatibility of the flame retardant with the polymer resin matrix, thereby reducing the amount of flame retardant added.

[0018] (2) The present invention provides a method for preparing a reactive flame retardant oxazoline benzoguanamine. The method adopts a two-step reaction to prepare oxazoline benzoguanamine. The total yield of the product can reach more than 85% and the product purity can reach more than 99.5%.

[0019] During the preparation process, the product yield is greatly improved by controlling the ratio of reaction raw materials, catalyst selection, and adjustment of temperature conditions. It has the advantages of simple preparation process, non-toxic materials, high efficiency, low cost, and no smoke at high temperature. DETAILED DESCRIPTION

[0020] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0021] The disclosure below provides many different embodiments or examples to realize different structures of the present invention. In order to simplify the disclosure of the present invention, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present invention. In addition, the present invention can repeat reference numbers and / or reference letters in different examples. This repetition is for the purpose of simplicity and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides various specific examples of processes and materials, but those of ordinary skill in the art can be aware of the application of other processes and / or the use of other materials.

[0022] This embodiment provides a reactive flame retardant oxazoline benzocyanate melamine, which is prepared using raw materials including isophthalonitrile, dicyandiamide and ethanolamine, and has a chemical structural formula of: .

[0023] The reactive flame retardant oxazoline benzocyanate melamine product provided in this embodiment is a substance that has not yet been registered with a CAS number.

[0024] Embodiment 1 This embodiment provides a method for preparing a reactive flame retardant oxazoline benzocyanate melamine, which uses isophthalonitrile, dicyandiamide and ethanolamine as raw materials and is prepared by a two-step synthesis method, specifically comprising the following steps: (1) Add the formulated amount of isophthalonitrile into a reactor, and add n-butanol, dicyandiamide and a catalyst in a volume 5 times that of isophthalonitrile in sequence. The reaction temperature in the reactor is 117°C, the pressure is 0.1-0.2 MPa, and the mixture is stirred, heated and refluxed for 4 hours; Among them, isophthalonitrile, dicyandiamide and catalyst are mixed and reacted in a raw material molar ratio of 1:1:0.01, and the reaction formula is as follows: ; (2) After the reaction is completed, the mixture is centrifuged, and the precipitate is washed three times with an equal volume of pure water to isophthalonitrile, and then centrifuged to obtain 2-cyanobenzoguanamine. The molar yield of the 2-cyanobenzoguanamine product is 99% and the purity is 99.6%; (3) Add the formulated amount of 2-cyanophenyl melamine into a reactor, and then add xylene, ethanolamine and a catalyst in an amount 5 times the volume of 2-cyanophenyl melamine in sequence. The reaction temperature in the reactor is 125°C, the pressure is 0.1-0.2 MPa, and the mixture is stirred, heated and refluxed for 4 hours; Among them, 2-cyanophenyl melamine, ethanolamine, and catalyst are mixed and reacted in a raw material molar ratio of 1:1:0.01, and the reaction formula is as follows: .

[0025] (4) After the reaction was completed, the pressure was reduced to 0.01 MPa to distill off the solvent, and an equal volume of purified water was added to wash three times with 2-cyanobenzoguanamine. The product was centrifuged to obtain the oxazolinebenzoguanamine product. The molar yield of the oxazolinebenzoguanamine was 85% and the purity was 99.5%.

[0026] (5) The solidified product after centrifugation is sent to a dryer, and after drying at a drying temperature of 60° C. for 2.0 hours, the dried product is sent to a pulverizer and pulverized into powder to obtain a finished product of reactive flame retardant oxazoline benzocyanate melamine.

[0027] In this embodiment, isophthalonitrile, dicyandiamide, ethanolamine, n-butanol and xylene are all of industrial grade; the catalyst in step (1) and step (3) is a mixture of zinc chloride, cobalt nitrate and sodium hydroxide.

[0028] Embodiment 2 This embodiment provides a method for preparing a reactive flame retardant oxazoline benzocyanate melamine, which uses isophthalonitrile, dicyandiamide and ethanolamine as raw materials and is prepared by a two-step synthesis method, specifically comprising the following steps: (1) Add the formulated amount of isophthalonitrile into a reactor, and add n-butanol, dicyandiamide and a catalyst in a volume 5 times that of isophthalonitrile in sequence. The reaction temperature in the reactor is 117°C, the pressure is 0.1-0.2 MPa, and the mixture is stirred, heated and refluxed for 7 hours; Among them, isophthalonitrile, dicyandiamide and catalyst are mixed and reacted in a raw material molar ratio of 1:4:0.5, and the reaction formula is as follows: ; (2) After the reaction is completed, the mixture is centrifuged, and the precipitate is washed three times with an equal volume of pure water to isophthalonitrile, and then centrifuged to obtain 2-cyanobenzoguanamine. The molar yield of the 2-cyanobenzoguanamine product is 99.2%, and the purity is 99.8%; (3) Add the formulated amount of 2-cyanophenyl melamine into a reactor, and then add xylene, ethanolamine and a catalyst in an amount 5 times the volume of 2-cyanophenyl melamine in sequence. The reaction temperature in the reactor is 125°C, the pressure is 0.1-0.2 Mpa, and the mixture is stirred, heated and refluxed for 7 hours; Among them, 2-cyanophenyl melamine, ethanolamine, and catalyst are mixed and reacted in a raw material molar ratio of 1:4:0.5, and the reaction formula is as follows: .

[0029] (4) After the reaction was completed, the pressure was reduced to 0.01 MPa to distill off the solvent, and an equal volume of purified water was added to wash three times with 2-cyanobenzoguanamine. The product oxazolinylbenzoguanamine was obtained by centrifugation. The molar yield of oxazolinylbenzoguanamine was 85.8% and the purity was 99.5%.

[0030] (5) The solidified product after centrifugation is sent to a dryer, and after drying at a drying temperature of 60° C. for 2.0 hours, the dried product is sent to a pulverizer and pulverized into powder to obtain a finished product of reactive flame retardant oxazoline benzocyanate melamine.

[0031] In this embodiment, isophthalonitrile, dicyandiamide, ethanolamine, n-butanol and xylene are all of industrial grade; the catalyst in step (1) and step (3) is a mixture of zinc chloride, cobalt nitrate and sodium hydroxide. Embodiment 3 This embodiment provides a method for preparing a reactive flame retardant oxazoline benzocyanate melamine, which uses isophthalonitrile, dicyandiamide and ethanolamine as raw materials and is prepared by a two-step synthesis method, specifically comprising the following steps: (1) Add the formulated amount of isophthalonitrile into a reactor, and add n-butanol, dicyandiamide and a catalyst in a volume 5 times that of isophthalonitrile in sequence. The reaction temperature in the reactor is 117°C, the pressure is 0.1-0.2 MPa, and the mixture is stirred, heated and refluxed for 5 hours; Among them, isophthalonitrile, dicyandiamide and catalyst are mixed and reacted in a raw material molar ratio of 1:3:0.3, and the reaction formula is as follows: ; (2) After the reaction is completed, the mixture is centrifuged, and the precipitate is washed three times with an equal volume of pure water to isophthalonitrile, and then centrifuged to obtain 2-cyanobenzoguanamine. The molar yield of the 2-cyanobenzoguanamine product is 99.2%, and the purity is 99.8%; (3) Add the formulated amount of 2-cyanophenyl melamine into a reactor, and then add xylene, ethanolamine and a catalyst in a volume 5 times that of 2-cyanophenyl melamine in sequence. The reaction temperature in the reactor is 125°C, the pressure is 0.1-0.2 MPa, and the mixture is stirred, heated and refluxed for 5 hours; Among them, 2-cyanophenyl melamine, ethanolamine, and catalyst are mixed and reacted in a raw material molar ratio of 1:3:0.3, and the reaction formula is as follows: .

[0032] (4) After the reaction was completed, the pressure was reduced to 0.01 MPa to distill off the solvent, and an equal volume of purified water was added to wash three times with 2-cyanobenzoguanamine. The product oxazolinylbenzoguanamine was obtained by centrifugation. The molar yield of oxazolinylbenzoguanamine was 85.5% and the purity was 99.8%.

[0033] (5) The solidified product after centrifugation is sent to a dryer, dried at 65°C for 1.75 hours, and then sent to a pulverizer to be pulverized into powder, thereby obtaining a finished product of reactive flame retardant oxazoline benzocyanate melamine.

[0034] In this embodiment, isophthalonitrile, dicyandiamide, ethanolamine, n-butanol and xylene are all of industrial grade; the catalyst in step (1) and step (3) is a mixture of cupric chloride, zinc acetate and potassium n-butoxide.

[0035] Embodiment 4 This embodiment provides a method for preparing a reactive flame retardant oxazoline benzocyanate melamine, which uses isophthalonitrile, dicyandiamide and ethanolamine as raw materials and is prepared by a two-step synthesis method, specifically comprising the following steps: (1) Add the formulated amount of isophthalonitrile into a reactor, and add n-butanol, dicyandiamide and a catalyst in a volume 5 times that of isophthalonitrile in sequence. The reaction temperature in the reactor is 117°C, the pressure is 0.1-0.2 MPa, and the mixture is stirred, heated and refluxed for 6 hours; Among them, isophthalonitrile, dicyandiamide and catalyst are mixed and reacted in a raw material molar ratio of 1:2:0.4, and the reaction formula is as follows: ; (2) After the reaction is completed, the mixture is centrifuged, and the precipitate is washed three times with an equal volume of pure water to isophthalonitrile, and then centrifuged to obtain 2-cyanobenzoguanamine. The molar yield of the 2-cyanobenzoguanamine product is 99%, and the purity is 99.7%; (3) Add the formulated amount of 2-cyanophenyl melamine into a reactor, and then add xylene, ethanolamine and a catalyst in an amount 5 times the volume of 2-cyanophenyl melamine in sequence. The reaction temperature in the reactor is 125°C, the pressure is 0.1-0.2 MPa, and the mixture is stirred, heated and refluxed for 6 hours; Among them, 2-cyanophenyl melamine, ethanolamine, and catalyst are mixed and reacted in a raw material molar ratio of 1:2:0.4, and the reaction formula is as follows: .

[0036] (4) After the reaction was completed, the pressure was reduced to 0.01 MPa to distill off the solvent, and an equal volume of purified water was added to wash three times with 2-cyanobenzoguanamine. The product oxazolinylbenzoguanamine was obtained by centrifugation. The molar yield of oxazolinylbenzoguanamine was 85.5% and the purity was 99.8%.

[0037] (5) The solidified product after centrifugation is sent to a dryer, dried at 65°C for 1.75 hours, and then sent to a pulverizer to be pulverized into powder, thereby obtaining a finished product of reactive flame retardant oxazoline benzocyanate melamine.

[0038] In this embodiment, isophthalonitrile, dicyandiamide, ethanolamine, n-butanol and xylene are all of industrial grade; the catalyst in step (1) and step (3) is a mixture of cupric chloride, zinc acetate and potassium n-butoxide.

[0039] Embodiment 5 This embodiment provides a method for preparing a reactive flame retardant oxazoline benzocyanate melamine, which uses isophthalonitrile, dicyandiamide and ethanolamine as raw materials and is prepared by a two-step synthesis method, specifically comprising the following steps: (1) Add the formulated amount of isophthalonitrile into a reactor, and add n-butanol, dicyandiamide and a catalyst in a volume 5 times that of isophthalonitrile in sequence. The reaction temperature in the reactor is 117°C, the pressure is 0.1-0.2 MPa, and the mixture is stirred, heated and refluxed for 7 hours; Among them, isophthalonitrile, dicyandiamide and catalyst are mixed and reacted in a raw material molar ratio of 1:4:0.5, and the reaction formula is as follows: ; (2) After the reaction is completed, the mixture is centrifuged, and the precipitate is washed three times with an equal volume of pure water to isophthalonitrile, and then centrifuged to obtain 2-cyanobenzoguanamine. The molar yield of the 2-cyanobenzoguanamine product is 99.3%, and the purity is 99.7%; (3) Add the formulated amount of 2-cyanophenyl melamine into a reactor, and then add xylene, ethanolamine and a catalyst in an amount 5 times the volume of 2-cyanophenyl melamine in sequence. The reaction temperature in the reactor is 125°C, the pressure is 0.1-0.2 Mpa, and the mixture is stirred, heated and refluxed for 7 hours; Among them, 2-cyanophenyl melamine, ethanolamine, and catalyst are mixed and reacted in a raw material molar ratio of 1:4:0.5, and the reaction formula is as follows: .

[0040] (4) After the reaction was completed, the pressure was reduced to 0.01 MPa to distill off the solvent, and an equal volume of purified water was added to wash three times with 2-cyanobenzoguanamine. The product was centrifuged to obtain the oxazolinebenzoguanamine product. The molar yield of the oxazolinebenzoguanamine was 85.6% and the purity was 99.8%.

[0041] (5) The solidified product after centrifugation is sent to a dryer, and after drying at a drying temperature of 60° C. for 2.0 hours, the dried product is sent to a pulverizer and pulverized into powder to obtain a finished product of reactive flame retardant oxazoline benzocyanate melamine.

[0042] In this embodiment, isophthalonitrile, dicyandiamide, ethanolamine, n-butanol and xylene are all of industrial grade; the catalyst in step (1) and step (3) is a mixture of copper sulfate, copper acetate, potassium hydroxide and sodium ethoxide.

[0043] Embodiment 6 This embodiment provides a method for preparing a reactive flame retardant oxazoline benzocyanate melamine, which uses isophthalonitrile, dicyandiamide and ethanolamine as raw materials and is prepared by a two-step synthesis method, specifically comprising the following steps: (1) Add the formulated amount of isophthalonitrile into a reactor, and add n-butanol, dicyandiamide and a catalyst in a volume 5 times that of isophthalonitrile in sequence. The reaction temperature in the reactor is 117°C, the pressure is 0.1-0.2 MPa, and the mixture is stirred, heated and refluxed for 7 hours; Among them, isophthalonitrile, dicyandiamide and catalyst are mixed and reacted in a raw material molar ratio of 1:4:0.5, and the reaction formula is as follows: ; (2) After the reaction is completed, the mixture is centrifuged, and the precipitate is washed three times with an equal volume of pure water to isophthalonitrile, and then centrifuged to obtain 2-cyanobenzoguanamine. The molar yield of the 2-cyanobenzoguanamine product is 99.3%, and the purity is 99.7%; (3) Add the formulated amount of 2-cyanophenyl melamine into a reactor, and then add xylene, ethanolamine and a catalyst in an amount 5 times the volume of 2-cyanophenyl melamine in sequence. The reaction temperature in the reactor is 125°C, the pressure is 0.1-0.2 Mpa, and the mixture is stirred, heated and refluxed for 7 hours; Among them, 2-cyanophenyl melamine, ethanolamine, and catalyst are mixed and reacted in a raw material molar ratio of 1:4:0.5, and the reaction formula is as follows: .

[0044] (4) After the reaction was completed, the pressure was reduced to 0.01 MPa to distill off the solvent, and an equal volume of purified water was added to wash three times with 2-cyanobenzoguanamine. The product was centrifuged to obtain the oxazolinebenzoguanamine product. The molar yield of the oxazolinebenzoguanamine was 85.3% and the purity was 99.8%.

[0045] (5) The solidified product after centrifugation is sent to a dryer and dried at 70°C for 1.5 hours. The dried product is then sent to a pulverizer and pulverized into powder to obtain a finished product of reactive flame retardant oxazoline-based benzocyanuramine.

[0046] In this embodiment, isophthalonitrile, dicyandiamide, ethanolamine, n-butanol and xylene are all of industrial grade; the catalyst in step (1) and step (3) is a mixture of copper sulfate, copper acetate, potassium hydroxide and sodium ethoxide.

[0047] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modifications to equivalent embodiments of the above disclosed technical contents without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A reactive flame retardant oxazoline benzoguanamine, characterized in that: It is prepared from raw materials including isophthalonitrile, dicyandiamide and ethanolamine, and its chemical structure is: 。 2. A method for preparing a reactive flame retardant oxazoline benzocyanate melamine, characterized in that: The synthesis is prepared by a two-step method, which specifically includes the following steps: (1) adding isophthalonitrile into a reaction kettle, and then sequentially adding a solvent, dicyandiamide and a catalyst, stirring and heating under reflux; (2) After the reaction is completed, centrifuge, wash the precipitate, and centrifuge to obtain 2-cyanophenyl melamine; (3) Add 2-cyanophenyl melamine into a reaction kettle, and then add a solvent, ethanolamine and a catalyst in sequence, and stir and heat under reflux; (4) after the reaction is completed, the solvent is distilled off under reduced pressure, washed, and centrifuged to obtain the oxazoline benzocyanate melamine product; (5) The solidified product after centrifugation is sent to a dryer for drying, and the dried product is sent to a crusher for crushing into powder, thereby obtaining a finished product of reactive flame retardant oxazoline-based benzocyanuric melamine.

3. The method for preparing the reactive flame retardant oxazoline benzocyanate melamine according to claim 2, characterized in that: The solvent in step (1) is n-butanol, and the solvent in step (3) is xylene.

4. The method for preparing the reactive flame retardant oxazoline benzoguanamine according to claim 3, characterized in that: The catalysts in step (1) and step (3) are one or more of zinc chloride, cupric chloride, cobalt nitrate, copper sulfate, zinc acetate, copper acetate potassium hydroxide, sodium hydroxide, potassium n-butoxide, and sodium ethoxide.

5. The method for preparing the reactive flame retardant oxazoline benzocyanate melamine according to claim 4, characterized in that: The two-step synthesis process is as follows: (1) isophthalonitrile: dicyandiamide: catalyst in a raw material molar ratio of 1: (1-4): (0.01-0.5) to prepare 2-cyanobenzoguanamine, the reaction formula is as follows: ； (2) 2-cyanobenzoguanamine: ethanolamine: catalyst are mixed in a raw material molar ratio of 1: (1-4): (0.01-0.5) to prepare oxazolinylbenzoguanamine, and the reaction formula is as follows: 。 6. The method for preparing the reactive flame retardant oxazoline benzoguanamine according to claim 2, characterized in that: The reaction temperature in the reactor in step (1) is 117° C. and the pressure is 0.1-0.2 MPa.

7. The method for preparing the reactive flame retardant oxazoline benzoguanamine according to claim 2, characterized in that: The reaction temperature in the reactor described in step (3) is 125° C., the pressure is 0.1-0.2 MPa, and the reduced pressure distillation pressure is 0.01 MPa.

8. The method for preparing the reactive flame retardant oxazoline benzocyanate melamine according to claim 2, characterized in that: The drying temperature and the corresponding drying time in step (5) are as follows: when the drying temperature is 60° C., the corresponding drying time is 2.0 hours.

9. The method for preparing the reactive flame retardant oxazoline benzoguanamine according to claim 2, characterized in that: The drying temperature and the corresponding drying time in step (5) are selected from one of the following parameters: When the drying temperature is 65°C, the corresponding drying time is 1.75 hours; Alternatively, when the drying temperature is 70° C., the corresponding drying time is 1.5 hours.

10. The method for preparing the reactive flame retardant oxazoline benzocyanate melamine according to claim 2, characterized in that: In step (2) and step (4), the mixture is washed with pure water three times.

Images