High-strength hyperbranched halogen-free flame retardant as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of flame retardants, and relates to a high-strength hyperbranched halogen-free flame retardant as well as a preparation method and application thereof, the preparation method comprises the following steps: preparing a modified isocyanate silane coupling agent from bis (3-aminophenyl) phenylphosphine oxide and 3-isocyanatopropyltriethoxysilane; the preparation method comprises the following steps: preparing a modified amino silane coupling agent from triglyceride isocyanurate and 3-aminopropyltriethoxysilane; the high-strength hyperbranched halogen-free flame retardant is prepared from a modified isocyanate silane coupling agent and a modified amino silane coupling agent. The silane coupling agent is modified according to the principle that an isocyanate group on the surface of the silane coupling agent can chemically react with a tertiary amine group and an epoxy group can react with an amino group, the two modified silane coupling agents form the hyperbranched flame retardant after being hydrolyzed, the highly branched structure enables the intermolecular force to be small, and the hyperbranched flame retardant has the advantages of high flame retardance and high flame retardancy. And the flame retardant shows excellent mechanical strength and excellent flame retardant effect.

Description

Technical Field

[0001] The invention belongs to the technical field of flame retardants and relates to a high-strength hyperbranched halogen-free flame retardant and a preparation method and application thereof. Background Art

[0002] Polyurethane, which has excellent strength, toughness and impact resistance, is widely used in many fields. However, it is also a highly flammable polymer material. The high heat release rate and smoke release during combustion will pose a serious threat to people's lives and property safety, which greatly limits its further application. Therefore, it is a vital task to improve the flame retardant properties of polyurethane and reduce its fire risk.

[0003] At present, the most effective way to improve the flame retardancy of polyurethane is to add flame retardants to the matrix. New flame retardants containing elements such as phosphorus, nitrogen, and silicon have attracted much attention because of their strong flame retardant effect and low price. However, with the development of application requirements, simple phosphorus-based flame retardants can no longer meet the needs, and thus many synergistic flame retardant systems have emerged, such as phosphorus-nitrogen synergistic flame retardants. Multi-element synergistic flame retardants have both excellent flame retardant properties and advantages such as good smoke suppression effect, environmental friendliness, and good thermal stability. Taking the research of Chinese patent (publication number CN115160371A) as an example, they use 2-bromoethylamine hydrobromide, triethylamine and hexachlorocyclotriphosphazene to mix and react to obtain nitrogen-phosphorus synergistic flame retardant, and apply it to polyurethane. Studies have shown that nitrogen-phosphorus synergistic flame retardants absorb a large amount of heat during thermal decomposition and have good thermal stability. However, the flame retardant reaction steps are complicated, and the compatibility with the substrate is poor. The addition of a large amount of flame retardants will cause the mechanical properties of the composite material to decline, which is not conducive to practical application.

[0004] In view of this, the development of new flame retardants with the characteristics of high efficiency flame retardancy, halogen-free, low smoke generation and high strength is of great significance to the promotion and use of polyurethane materials. Summary of the invention

[0005] The present invention aims at the deficiencies of flame retardants in the prior art and provides a high-strength hyperbranched halogen-free flame retardant and a preparation method and application thereof.

[0006] One object of the present invention is achieved by the following technical solutions:

[0007] A method for preparing a high-strength hyperbranched halogen-free flame retardant, the preparation method comprising the following steps:

[0008] S1, dissolving bis(3-aminophenyl)phenylphosphine oxide in a solvent to obtain a first solution; dissolving 3-isocyanatepropyltriethoxysilane and a catalyst in a solvent to obtain a second solution; adding the first solution to the second solution and heating the solution to react, and obtaining a modified isocyanate silane coupling agent (AURORA-IPTS) after precipitation, filtration, washing and drying;

[0009] S2, dissolving triglycerol isocyanurate (TGIC) in a solvent to obtain a third solution; dissolving 3-aminopropyltriethoxysilane and a catalyst in a solvent to obtain a fourth solution; adding the third solution to the fourth solution and heating the solution to react, and obtaining a modified aminosilane coupling agent (TGIC-APTS) after precipitation, filtration, washing and drying;

[0010] S3. Dissolve the modified isocyanate silane coupling agent (AURORA-IPTS) and the modified aminosilane coupling agent (TGIC-APTS) in a solvent to obtain a fifth solution, and add water to the solvent to obtain a sixth solution; add the fifth solution to the sixth solution, heat the solution and adjust the pH, then remove the solvent by rotary evaporation, and then wash and dry to obtain a high-strength hyperbranched halogen-free flame retardant (HBNPSi).

[0011] Preferably, the bis(3-aminophenyl)phenylphosphine oxide has a structural formula as shown in Formula I:

[0012]

[0013] Preferably, the 3-isocyanatepropyltriethoxysilane has a structural formula as shown in Formula II:

[0014]

[0015] The invention utilizes the isocyanate groups on the surface of 3-isocyanatepropyltriethoxysilane to chemically react with the amine groups in bis(3-aminophenyl)phenylphosphine oxide, thereby introducing phosphorus and nitrogen elements into the isocyanate silane coupling agent.

[0016] Preferably, the triglycerol isocyanurate (TGIC) has a structural formula as shown in Formula III:

[0017]

[0018] Preferably, the 3-aminopropyltriethoxysilane has a structural formula as shown in Formula IV:

[0019]

[0020] The invention utilizes the amino group in 3-aminopropyltriethoxysilane to react chemically with the epoxy group in triglycerol isocyanurate, thereby introducing nitrogen element into the aminosilane coupling agent.

[0021] Preferably, the catalyst mentioned herein is dibutyltin dilaurate (DBTDL).

[0022] Preferably, the solvent mentioned herein includes one or more of tetrahydrofuran, methanol, ethanol, isopropanol, ethyl acetate, acetone, and methyl ethyl ketone, and tetrahydrofuran is further preferred.

[0023] Preferably, in step S1, the mass ratio of bis(3-aminophenyl)phenylphosphine oxide to 3-isocyanatepropyltriethoxysilane is (0.5-5.0):1.0.

[0024] Preferably, in step S1, the concentration of bis(3-aminophenyl)phenylphosphine oxide in the first solution is 0.05 to 2.5 g / mL.

[0025] Preferably, in step S1, the ratio of 3-isocyanatepropyltriethoxysilane, catalyst and solvent in the second solution is (3-5) g: (0.1-0.5) g: (10-100) mL.

[0026] Preferably, in step S1, the mass ratio of the first solution to the second solution is 1:(0.5-2.0).

[0027] Preferably, in step S1, the reaction is carried out under an inert gas atmosphere, and the temperature is raised to 55-75° C. and then stirred for reaction for 1-5 hours.

[0028] The inert gas atmosphere mentioned herein may be a mixed gas of one or more of nitrogen, argon, and helium.

[0029] Preferably, in step S1, anhydrous ethanol is used for precipitation, filtration and washing at least 3 times, and drying at 90-100° C. for 10-20 hours.

[0030] Preferably, the reaction process in step S1 is shown in the following reaction formula I:

[0031]

[0032] In the step S1, the reaction process of reaction formula I uses bis(3-aminophenyl)phenylphosphine oxide as a modifier, and utilizes the surface amino groups thereof to chemically react with the isocyanate groups on 3-isocyanatepropyltriethoxysilane, thereby modifying the isocyanate silane coupling agent to obtain a modified isocyanate silane coupling agent (AURORA-IPTS).

[0033] Preferably, in step S2, the mass ratio of triglycerol isocyanurate to 3-aminopropyltriethoxysilane is (0.4-4.0):1.0.

[0034] Preferably, in step S2, the concentration of triglyceride isocyanurate in the third solution is 0.05-2.5 g / mL.

[0035] Preferably, in step S2, the ratio of 3-aminopropyltriethoxysilane, catalyst and solvent in the fourth solution is (3-6) g: (0.1-0.5) g: (10-100) mL.

[0036] Preferably, in step S2, the mass ratio of the third solution to the fourth solution is 1:(0.5-2.0).

[0037] Preferably, in step S2, the reaction is carried out under an inert gas atmosphere, and the temperature is raised to 55-75° C. and then stirred for reaction for 1-5 hours.

[0038] Preferably, in step S2, anhydrous ethanol is used for precipitation, filtration and washing at least 3 times, and drying at 90-100° C. for 10-20 hours.

[0039] Preferably, the reaction process in step S2 is shown in the following reaction formula II:

[0040]

[0041] In step S2, the reaction process of reaction formula II uses triglycerol isocyanurate as a modifier, and the epoxy groups on the surface of triglycerol are used to react chemically with the amino groups on 3-aminopropyltriethoxysilane, thereby modifying the aminosilane coupling agent to obtain a modified aminosilane coupling agent (TGIC-APTS).

[0042] Preferably, in step S3, the mass ratio of the modified isocyanate silane coupling agent to the modified aminosilane coupling agent is 1.0:(0.5-3.0).

[0043] Preferably, in step S3, the concentration of the modified isocyanate silane coupling agent in the fifth solution is 0.02-1.5 g / mL.

[0044] Preferably, in step S3, the mass ratio of water to solvent in the sixth solution is 1.0:(5.0-10.0).

[0045] Preferably, in step S3, the mass ratio of the fifth solution to the sixth solution is 1:(0.5-2.0).

[0046] Preferably, in step S3, after the temperature is raised to 55-75° C., an acid solution is added to adjust the pH to 3.5-4.5 and the reaction is continued with stirring for 1-5 hours.

[0047] Preferably, the acid solution for adjusting pH mentioned herein can be one or more of hydrochloric acid, sulfuric acid, nitric acid, acetic acid and phosphoric acid.

[0048] Preferably, in step S3, anhydrous ethanol is used for precipitation, filtration and washing at least 3 times, and drying at 90-100° C. for 10-20 hours.

[0049] Preferably, the reaction process in step S3 is shown in the following reaction formula III:

[0050]

[0051] In the step S3, the reaction process of reaction formula III uses a modified isocyanate silane coupling agent (AURORA-IPTS) and a modified aminosilane coupling agent (TGIC-APTS) to hydrolyze with H2O, wherein the silicon-oxygen bond breaks under the action of water to generate a silicon hydroxyl compound, and then the silicon hydroxyl group undergoes a condensation reaction with other silicon hydroxyl groups or silicon-oxygen bonds in water to obtain a high-strength hyperbranched halogen-free flame retardant (HBNPSi).

[0052] The second object of the present invention is achieved by the following technical solutions:

[0053] A high-strength hyperbranched halogen-free flame retardant is prepared by the above preparation method.

[0054] The third object of the present invention is achieved by the following technical solutions:

[0055] A high-strength flame-retardant and fire-resistant polymer material, wherein the raw materials for preparing the high-strength flame-retardant and fire-resistant polymer material include the high-strength hyperbranched halogen-free flame retardant.

[0056] Preferably, the high-strength flame-retardant and fire-resistant polymer material comprises 10-40 wt % of a high-strength hyperbranched halogen-free flame-retardant polyolefin flame retardant and 60-90 wt % of polyurethane.

[0057] Compared with the prior art, the present invention has the following beneficial effects:

[0058] 1. The present invention provides a high-strength hyperbranched halogen-free flame retardant. By regulating the structure of the molecular chain and introducing a grafted modified silane coupling agent, the chain entanglement between the molecular chains and the hydrogen bonding between the polymer molecules are utilized to prepare a hyperbranched polymer with high strength and containing phosphorus, nitrogen and silicon elements as a flame retardant. The phosphorus, nitrogen and silicon elements have a synergistic effect. These elements exert flame retardant properties in different mechanisms during the combustion process, which helps the flame retardant to achieve excellent flame retardant effects.

[0059] 2. The present invention provides a high-strength hyperbranched halogen-free flame retardant, which modifies the silane coupling agent by utilizing the principle that the isocyanate group on the surface of the silane coupling agent can chemically react with the tertiary amine group and the epoxy group can react with the amino group. The two modified silane coupling agents are hydrolyzed to form a hyperbranched flame retardant, which has a highly branched structure in space, small intermolecular forces, and no entanglement within and between molecules, thereby improving the stability and consistency of the material. The flame retardant exhibits excellent mechanical strength, which enables it to have a longer service life in harsh environments.

[0060] 3. The high-strength hyperbranched halogen-free flame retardant provided by the present invention adopts a three-dimensional highly branched structure design so that the flame retardant end is rich in epoxy groups, which can react with the amino group in the polyurethane, which is beneficial to further combine the flame retardant with the resin system, thereby enhancing the overall interface strength and improving the mechanical properties of the polyurethane composite material.

[0061] 4. In a high-strength hyperbranched halogen-free flame retardant provided by the present invention, hydrogen bonds are formed between the modified silane coupling agent molecules, which have self-repairing ability, can repair thermal damage by rearrangement of molecular chains at high temperatures, can effectively dissipate energy during stretching, and improve the mechanical strength and toughness of polyurethane composite materials.

[0062] 5. The high-strength hyperbranched halogen-free flame retardant provided by the present invention has a three-dimensional highly branched structure that increases the chain entanglement between molecules, helps to maintain the stability of the polyurethane composite material at high temperatures, thereby improving the thermal stability of the polyurethane composite material. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 This is a SEM characterization image of the high-strength hyperbranched halogen-free flame retardant of Example 1 of the present invention. DETAILED DESCRIPTION

[0064] The technical solution of the present invention is further described below in conjunction with specific embodiments and drawings. It should be understood that the specific embodiments described herein are only used to illustrate the present invention and are not used to limit the scope of the present invention. And the drawings used herein are only for better illustrating the disclosed content of the present invention and do not have a limiting effect on the scope of protection. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims attached to this application.

[0065] Example 1

[0066] The preparation method of the high-strength hyperbranched halogen-free flame retardant of this embodiment comprises the following steps:

[0067] S1. Add 6.8 g of bis(3-aminophenyl)phenylphosphine oxide to a single-necked flask filled with 40 mL of tetrahydrofuran, stir and dissolve completely under ultrasound, which is the first solution; at the same time, add 4.9 g of 3-isocyanatepropyltriethoxysilane and 0.2 g of catalyst dibutyltin dilaurate to a single-necked flask filled with 40 mL of tetrahydrofuran, stir and dissolve completely under ultrasound, which is the second solution; under a nitrogen atmosphere, gradually drop the first solution into the second solution at room temperature, heat to 60°C, maintain the temperature and stir for 2 hours; finally, precipitate and filter through anhydrous ethanol, wash three times with anhydrous ethanol, put into a vacuum oven at 100°C and dry for 12 hours to obtain a modified isocyanate silane coupling agent (AURORA-IPTS);

[0068] S2, adding 5.9g of triglycerol isocyanurate to a single-necked flask filled with 40mL of tetrahydrofuran, stirring and ultrasonicating until completely dissolved, which is the third solution; at the same time, adding 4.4g of 3-aminopropyltriethoxysilane and 0.2g of catalyst dibutyltin dilaurate to a single-necked flask filled with 40mL of tetrahydrofuran, stirring and ultrasonicating until completely dissolved, which is the fourth solution; under a nitrogen atmosphere, the third solution is gradually dropped into the fourth solution at room temperature, the temperature is raised to 60°C, and the temperature is maintained and stirred for 2h; finally, the solution is precipitated and filtered through anhydrous ethanol, washed three times with anhydrous ethanol, and dried in a vacuum oven at 100°C for 12h to obtain a modified aminosilane coupling agent (TGIC-APTS);

[0069] S3. Add 5.9 g of modified isocyanate silane coupling agent and 5.2 g of modified aminosilane coupling agent prepared in S1 and S2 into a single-necked flask filled with 40 mL of tetrahydrofuran, stir and dissolve completely under ultrasonic action, which is the fifth solution; after completely dissolving 0.72 mL of deionized water in 5 mL of tetrahydrofuran, gradually add the sixth solution dropwise at room temperature, heat to 60°C, adjust the pH to 4 with hydrochloric acid (0.1 M), maintain the temperature and stir for 2 hours; after removing tetrahydrofuran by rotary evaporation, wash three times with anhydrous ethanol, put it in a vacuum oven at 100°C and dry it for 12 hours to obtain a hyperbranched nitrogen-phosphorus-silicon flame retardant (HBNPSi).

[0070] The hyperbranched nitrogen-phosphorus-silicon flame retardant (HBNPSi) prepared in Example 1 was observed by electron microscopy (see Figure 1 ). Figure 1 This is a SEM characterization image of the high-strength hyperbranched halogen-free flame retardant of Example 1 of the present invention. Figure 1 It can be seen that the present invention successfully prepared a hyperbranched polymer flame retardant with high strength and containing phosphorus, nitrogen and silicon elements by regulating the structure of the molecular chain and introducing a grafted modified silane coupling agent, utilizing the chain entanglement between the molecular chains and the hydrogen bonding between polymer molecules.

[0071] Example 2

[0072] The difference between the preparation method of the high-strength hyperbranched halogen-free flame retardant in this embodiment and that in Embodiment 1 is that 13.6 g of bis(3-aminophenyl)phenylphosphine oxide is used in step S1.

[0073] Example 3

[0074] The difference between the preparation method of the high-strength hyperbranched halogen-free flame retardant in this embodiment and that in Embodiment 1 is that 10.2 g of bis(3-aminophenyl)phenylphosphine oxide is used in step S1.

[0075] Example 4

[0076] The difference between the preparation method of the high-strength hyperbranched halogen-free flame retardant in this embodiment and that in Embodiment 1 is that 3.4 g of bis(3-aminophenyl)phenylphosphine oxide is used in step S1.

[0077] Example 5

[0078] The difference between the preparation method of the high-strength hyperbranched halogen-free flame retardant in this embodiment and that in Embodiment 1 is that 17.6 g of triglycerol isocyanurate is used in step S2.

[0079] Example 6

[0080] The difference between the preparation method of the high-strength hyperbranched halogen-free flame retardant in this embodiment and that in Embodiment 1 is that 3.0 g of triglycerol isocyanurate is used in step S2.

[0081] Example 7

[0082] The difference between the preparation method of the high-strength hyperbranched halogen-free flame retardant in this embodiment and that in Embodiment 1 is that 10.4 g of the modified aminosilane coupling agent is used in step S3.

[0083] Example 8

[0084] The difference between the preparation method of the high-strength hyperbranched halogen-free flame retardant in this embodiment and that in Embodiment 1 is that 3.1 g of the modified aminosilane coupling agent is used in step S3.

[0085] Comparative Example 1

[0086] The difference between this comparative example and Example 1 is that 27.2 g of bis(3-aminophenyl)phenylphosphine oxide is used in step S1.

[0087] Comparative Example 2

[0088] The difference between this comparative example and Example 1 is that the amount of bis(3-aminophenyl)phenylphosphine oxide used in step S1 is 1.7 g.

[0089] Comparative Example 3

[0090] The difference between this comparative example and Example 1 is that 23.6 g of triglycerol isocyanurate is used in step S2.

[0091] Comparative Example 4

[0092] The difference between this comparative example and Example 1 is that 1.5 g of triglycerol isocyanurate is used in step S2.

[0093] Comparative Example 5

[0094] The difference between this comparative example and Example 1 is that step S1 of Example 1 is not performed, and specifically comprises the following steps:

[0095] Step S1 is the same as step S2 of Example 1.

[0096] S2. Add 5.2 g of the modified aminosilane coupling agent prepared in S1 into a single-necked flask containing 40 mL of tetrahydrofuran, stir and dissolve completely under ultrasonic action, which is the third solution; after completely dissolving 0.72 mL of deionized water in 5 mL of tetrahydrofuran, gradually add the fourth solution dropwise at room temperature, heat to 60°C, adjust the pH to 4 with hydrochloric acid (0.1 M), maintain the temperature and stir for 2 hours; after removing tetrahydrofuran by rotary evaporation, wash three times with anhydrous ethanol, put it in a vacuum oven at 100°C and dry it for 12 hours to obtain the final product.

[0097] Comparative Example 6

[0098] The difference between this comparative example and Example 1 is that step S2 of Example 1 is not performed, and specifically comprises the following steps:

[0099] Step S1 is the same as step S1 in Example 1.

[0100] S2. Add 5.9 g of the modified isocyanate silane coupling agent prepared in S1 into a single-necked flask containing 40 mL of tetrahydrofuran, stir and dissolve completely under ultrasonic action, which is the third solution; after completely dissolving 0.72 mL of deionized water in 5 mL of tetrahydrofuran, gradually add the fourth solution dropwise at room temperature, heat to 60°C, adjust the pH to 4 with hydrochloric acid (0.1 M), maintain the temperature and stir for 2 hours; after removing tetrahydrofuran by rotary evaporation, wash three times with anhydrous ethanol, put it in a vacuum oven at 100°C and dry it for 12 hours to obtain the final product.

[0101] Comparative Example 7

[0102] The difference between this comparative example and Example 1 is that all raw materials are directly mixed for preparation, which specifically includes the following steps:

[0103] Weigh 6.8 g of bis(3-aminophenyl)phenylphosphine oxide, 4.9 g of 3-isocyanatepropyltriethoxysilane, 5.9 g of isocyanuric acid triglyceride and 4.4 g of 3-aminopropyltriethoxysilane, stir and mix them evenly to obtain the final product.

[0104] The final products prepared in the above examples and comparative examples were applied to isocyanate / polyol polyurethane, wherein the final products accounted for 25wt% of the total mass; the mechanical properties and flame retardant properties of the obtained polymer material were tested, and the specific results are shown in Table 1.

[0105] Table 1 Performance test results of embodiments and comparative examples

[0106] Example Tensile strength / Mpa Elongation at break / % Flame retardant Example 1 46.8 694 V-0 Example 2 39.6 815 V-0 Example 3 43.2 746 V-0 Example 4 44.4 734 V-1 Example 5 45.3 714 V-0 Example 6 39.8 803 V-1 Example 7 45.7 701 V-0 Example 8 40.2 807 V-0 Comparative Example 1 27.2 927 V-1 Comparative Example 2 28.8 909 V-2 Comparative Example 3 30.8 874 V-1 Comparative Example 4 31.8 863 V-1 Comparative Example 5 30.1 879 HB Comparative Example 6 25.8 945 V-2 Comparative Example 7 21.6 631 V-1

[0107] Among them, the flame retardancy level decreases gradually from V-0, V-1, V-2 to HB. The specific standards are as follows:

[0108] V-0: After two 10-second combustion tests on the sample, the flame goes out within 30 seconds and no burning material falls off;

[0109] V-1: After two 10-second combustion tests on the sample, the flame goes out within 60 seconds and no burning material falls off;

[0110] V-2: After two 10-second combustion tests on the sample, the flame goes out within 60 seconds, and the burning material may fall off;

[0111] HB: The lowest flame retardant grade. According to the UL94 standard, for samples with a thickness of 3 to 13 mm, the burning speed is less than 40 mm / min; for samples with a thickness of less than 3 mm, the burning speed is less than 70 mm / min; or the sample goes out before the 100 mm / min mark.

[0112] As shown in Table 1, it can be seen from Examples 1 to 8 that the polyurethane composite materials obtained by using the materials and proportions in the technical solution of the present invention have good mechanical properties and heat resistance; in Comparative Example 1, due to the excessive addition of bis(3-aminophenyl)phenylphosphine oxide, the molecular agglomeration and uneven distribution lead to a decrease in the mechanical properties of the polyurethane composite material; in Comparative Example 2, the amount of bis(3-aminophenyl)phenylphosphine oxide added is too low, and the mechanical properties are not well enhanced. At the same time, the reduction of phosphorus element leads to a decrease in the heat resistance of the polyurethane composite material; in Comparative Example 3, the amount of triglycerol isocyanurate added is too high, so that the grafting ratio is increased, the free volume is reduced, the hardness of the obtained polyurethane composite material is large, and the elongation at break is reduced; in Comparative Example 4, the amount of triglycerol isocyanurate added is too high, so that the grafting ratio is increased, the free volume is reduced, the hardness of the obtained polyurethane composite material is large, and the elongation at break is reduced. The amount is too low, the reduction of phosphorus element leads to the decrease of heat resistance of polyurethane composite material, and the reduction of epoxy group makes it impossible for flame retardant to be effectively grafted on polyurethane, the tensile strength of the obtained polyurethane composite material is reduced, and the mechanical properties are reduced; in comparative example 5, no modified isocyanate silane coupling agent is added, lacking the synergistic effect of phosphorus element, and the overall flame retardant performance is deteriorated; in comparative example 6, no modified aminosilane coupling agent is added, the grafting ratio is significantly reduced, the tensile strength of the obtained polyolefin cable material is reduced, and the lack of nitrogen element makes its flame retardant performance unable to reach V-0, and the heat aging resistance is reduced; in comparative example 7, polyurethane is directly physically mixed with various raw materials, and no chemical reaction is carried out between the raw materials, resulting in uneven distribution between the components, resulting in greatly reduced mechanical properties of the final product.

[0113] The various aspects, embodiments, and features of the present invention should be considered to be illustrative in all aspects and not limiting of the present invention, the scope of which is defined solely by the claims. Other embodiments, modifications, and uses will be apparent to those skilled in the art without departing from the spirit and scope of the claimed invention.

[0114] In the preparation method of the present invention, the order of each step is not limited to the order listed. For those skilled in the art, without creative work, the order of each step is also within the protection scope of the present invention. In addition, two or more steps or actions can be performed simultaneously.

[0115] Finally, it should be noted that the specific embodiments described herein are merely examples of the present invention, and are not intended to limit the implementation methods of the present invention. A person skilled in the art of the present invention may make various modifications or supplements to the specific embodiments described, or replace them in a similar manner. It is not necessary and impossible to provide all examples of all implementation methods here. However, these obvious changes or modifications derived from the essential spirit of the present invention still fall within the scope of protection of the present invention, and interpreting them as any additional limitation is contrary to the spirit of the present invention.

Claims

1. A method for preparing a high-strength hyperbranched halogen-free flame retardant, characterized in that: The preparation method comprises the following steps: S1, dissolving bis(3-aminophenyl)phenylphosphine oxide in a solvent to obtain a first solution; dissolving 3-isocyanatepropyltriethoxysilane and a catalyst in a solvent to obtain a second solution; adding the first solution to the second solution and heating the solution to react, and obtaining a modified isocyanate silane coupling agent after precipitation, filtration, washing and drying; S2, dissolving triglycerol isocyanurate in a solvent to obtain a third solution; dissolving 3-aminopropyltriethoxysilane and a catalyst in a solvent to obtain a fourth solution; adding the third solution to the fourth solution and heating the solution to react, and obtaining a modified aminosilane coupling agent after precipitation, filtration, washing and drying; S3, dissolving the modified isocyanate silane coupling agent and the modified aminosilane coupling agent in a solvent to obtain a fifth solution, and adding water to the solvent to obtain a sixth solution; adding the fifth solution to the sixth solution to react at a high temperature and adjusting the pH, and then removing the solvent by rotary evaporation, and then washing and drying to obtain a high-strength hyperbranched halogen-free flame retardant; The bis(3-aminophenyl)phenylphosphine oxide has a structural formula as shown in Formula I: The 3-isocyanatepropyltriethoxysilane has a structural formula as shown in Formula II: The triglycerol isocyanurate (TGIC) has a structural formula as shown in Formula III: The 3-aminopropyltriethoxysilane has a structural formula as shown in Formula IV:

2. The preparation method according to claim 1, characterized in that: In the step S1, the mass ratio of bis(3-aminophenyl)phenylphosphine oxide to 3-isocyanatepropyltriethoxysilane is (0.5-5.0):1.

0.

3. The preparation method according to claim 1, characterized in that: In step S1, the concentration of bis(3-aminophenyl)phenylphosphine oxide in the first solution is 0.05 to 2.5 g / mL; And / or, in step S1, the ratio of 3-isocyanatepropyltriethoxysilane, catalyst and solvent in the second solution is (3-5) g: (0.1-0.5) g: (10-100) mL; And / or, in step S1, the mass ratio of the first solution to the second solution is 1:(0.5-2.0); And / or, in step S1, the reaction is carried out under an inert gas atmosphere, the temperature is raised to 55-75° C., and the reaction is stirred for 1-5 hours; And / or, in step S1, anhydrous ethanol is used for precipitation, filtration and washing at least 3 times, and drying at 90-100° C. for 10-20 hours.

4. The preparation method according to claim 1, characterized in that: In the step S2, the mass ratio of triglycerol isocyanurate to 3-aminopropyltriethoxysilane is (0.4-4.0):1.

0.

5. The preparation method according to claim 1, characterized in that: In step S2, the concentration of triglycerol isocyanurate in the third solution is 0.05 to 2.5 g / mL; And / or, in step S2, the ratio of 3-aminopropyltriethoxysilane, catalyst and solvent in the fourth solution is (3-6) g: (0.1-0.5) g: (10-100) mL; And / or, in step S2, the mass ratio of the third solution to the fourth solution is 1:(0.5-2.0); And / or, in step S2, the reaction is carried out under an inert gas atmosphere, the temperature is raised to 55-75° C., and the reaction is stirred for 1-5 hours; And / or, in step S2, anhydrous ethanol is used for precipitation, filtration and washing at least 3 times, and drying at 90-100° C. for 10-20 hours.

6. The preparation method according to claim 1, characterized in that: In the step S3, the mass ratio of the modified isocyanate silane coupling agent to the modified aminosilane coupling agent is 1.0:(0.5-3.0).

7. The preparation method according to claim 1, characterized in that: In step S3, the concentration of the modified isocyanate silane coupling agent in the fifth solution is 0.02 to 1.5 g / mL; And / or, in step S3, the mass ratio of water to solvent in the sixth solution is 1.0:(5.0-10.0); And / or, in step S3, the mass ratio of the fifth solution to the sixth solution is 1:(0.5-2.0); And / or, in step S3, after heating to 55-75° C., an acid solution is added to adjust the pH to 3.5-4.5 and the reaction is continued with stirring for 1-5 hours; And / or, in step S3, anhydrous ethanol is used for precipitation, filtration and washing at least 3 times, and drying at 90-100° C. for 10-20 hours.

8. A high-strength hyperbranched halogen-free flame retardant, characterized in that: It is prepared by the preparation method according to any one of claims 1 to 7.

9. A high-strength flame-retardant and fire-resistant polymer material, characterized in that: The raw material for preparing the high-strength flame-retardant and fire-resistant polymer material includes a high-strength hyperbranched halogen-free flame retardant as described in claim 8.

10. A high-strength flame-retardant and fire-resistant polymer material according to claim 9, characterized in that: The high-strength flame-retardant and fire-resistant polymer material comprises 10-40 wt% of a high-strength hyperbranched halogen-free flame-retardant polyolefin flame retardant and 60-90 wt% of polyurethane.

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