阅读说明：本技术 一种氨基封端的磷-硅-硼多功能元素阻燃剂及制备方法 (Amino-terminated phosphorus-silicon-boron multifunctional element flame retardant and preparation method thereof ) 是由 陈维旺 董雨桐 周晓猛 于 2021-09-18 设计创作，主要内容包括：一种氨基封端的磷-硅-硼多功能元素阻燃剂及制备方法。阻燃剂化学结构式如下：本发明效果：将磷、硅、硼三种阻燃元素结合到同一分子中,并采用氨基封端的方式,多功能元素能够协效阻燃,因此可有效提高阻燃效果和综合性能；能够在气相和凝聚相发挥阻燃作用,具有良好的热稳定性和成炭能力；不含卤素元素,不会对环境造成危害；具有活性端氨基,可通过交联、缩合等反应与基材进行化学接枝,使聚合物具有本征阻燃功能。制备方法具有反应条件温和、反应过程可控、产率较高等特点。(An amino-terminated phosphorus-silicon-boron multifunctional element flame retardant and a preparation method thereof. The chemical structural formula of the flame retardant is as follows: the invention has the following effects: three flame-retardant elements of phosphorus, silicon and boron are combined into the same molecule, and an amino end-capping mode is adopted, so that the multifunctional element can synergistically retard flame, and the flame-retardant effect and the comprehensive performance can be effectively improved; the flame retardant can play a flame retardant role in a gas phase and a condensed phase, and has good thermal stability and char forming capability; the halogen element is not contained, so that the environment is not damaged; has active terminal amino group, and can be chemically grafted with a base material through reactions such as crosslinking, condensation and the like, so that the polymer has an intrinsic flame retardant function. The preparation method has the following stepsMild reaction condition, controllable reaction process, high yield and the like.)

1. An amino-terminated phosphorus-silicon-boron multifunctional element flame retardant is characterized in that: the chemical structural formula of the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant is as follows:

2. a method for preparing the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant of claim 1, which is characterized by comprising the following steps: the preparation method comprises the following steps which are carried out in sequence:

(1) preparing an intermediate containing phosphorus-silicon element: in an inert gas environment, fully mixing 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide with vinyl triethoxysilane in an organic solvent under the action of a catalyst, continuously stirring at 80 ℃, and reacting for 24 hours to obtain a phosphorus-silicon element-containing intermediate;

(2) preparing an amino-terminated phosphorus-silicon-boron multifunctional element flame retardant: and adding trimethylboroxine and 3-aminopropyltriethoxysilane into the phosphorus-silicon element-containing intermediate, continuing to react for 4-10 hours at 100 ℃, filtering or rotationally evaporating the reaction liquid, washing and drying the solid matters by absolute ethyl alcohol to obtain the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant.

3. The method for preparing the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant according to claim 2, characterized in that: in the step (1), the molar ratio of the 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide to the vinyl triethoxysilane to the catalyst to the organic solvent is 100:100:5: 1000-2000.

4. The method for preparing the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant according to claim 2, characterized in that: in the step (2), the molar ratio of the phosphorus-silicon element-containing intermediate to trimethylboroxine to 3-aminopropyltriethoxysilane is 1-4: 1-2: 1-4.

5. The method for preparing the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant according to claim 2, characterized in that: in the step (1), the inert gas is selected from any one of nitrogen, helium and argon.

6. The method for preparing the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant according to claim 2, characterized in that: in the step (1), the catalyst is 2, 2-azobisisobutyronitrile.

7. The method for preparing the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant according to claim 2, characterized in that: in the step (1), the organic solvent is diethylene glycol dimethyl ether.

8. The method for preparing the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant according to claim 2, characterized in that: in the step (2), the drying temperature is 60 ℃.

Technical Field

The invention belongs to the technical field of halogen-free flame retardants and preparation thereof, and particularly relates to an amino-terminated phosphorus-silicon-boron multifunctional element flame retardant and a preparation method thereof.

Background

Common thermoplastics or thermosets are readily flammable and are often treated with flame retardant modifications. The halogen flame retardant has the characteristics of high flame retardant efficiency, small filling amount and the like, and is the most widely applied flame retardant at present. However, since halogen flame retardants generate toxic substances such as dioxin and furan during combustion and are not degradable, the application of such flame retardants has been internationally limited, and some of them have been banned from use.

The halogen-free flame retardant mainly comprises phosphorus, nitrogen, silicon, boron, metal hydroxide, an intumescent flame retardant and the like. The halogen-free flame retardant has the characteristic of environmental friendliness, so the application range and the application field of the halogen-free flame retardant are continuously expanded. However, these flame retardants have various problems when used alone. For example, although phosphorus-based flame retardants can exhibit flame-retardant effects in the gas phase and condensed phase, they are difficult to char on oxygen-free substrates. The silicon flame retardant can form a Si-O-Si cross-linked structure during combustion, and covers the surface of combustible to play a role in protection, but the silicon flame retardant also has the problems of incompatibility with flame-retardant base materials and the like.

In order to obtain a better flame retardant effect and balance the relationship among the performances, the dosage and the cost of various flame retardants, the method is a common method for making up the deficiency of a single flame retardant element by fusing various flame retardant elements, and has become a current research hotspot. Chinese patent application No. CN201110026154 discloses a caged bicyclic phosphate siloxane flame retardant, which contains rigid caged bicyclic phosphate group and silicon element, and the phosphorus-silicon dual-function element design in the flame retardant can play a good synergistic flame retardant effect, shows good thermal stability and char formation ability, and can effectively reduce smoke generated in combustion. However, when the flame retardant is used for flame retarding nylon 6, the addition amount of the flame retardant exceeds 20 percent and can reach the grade of UL94-V0, so that the using amount of the flame retardant is higher. Chinese patent application No. CN200710068001 discloses a polyborosiloxane flame retardant and a preparation method thereof, the method solves the problems of difficult compounding and uneven dispersion caused by adding a boron compound and siloxane into a base material through physical mixing, and the flame retardant has good heat resistance and strong moisture absorption resistance, but only has certain flame retardance on polycarbonate with higher char formation.

In general, although the multifunctional element flame retardant disclosed in the prior art can show good flame retardant performance, the multifunctional element flame retardant also has the defects of large addition amount, single action range and the like. Therefore, there is a need to further develop halogen-free efficient flame retardants to better meet the diverse application requirements.

Disclosure of Invention

In order to solve the problems, the invention aims to provide an amino-terminated phosphorus-silicon-boron multifunctional element flame retardant and a preparation method thereof.

In order to achieve the purpose, the chemical structural formula of the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant provided by the invention is as follows:

the preparation method of the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant comprises the following steps in sequence:

(1) preparing an intermediate containing phosphorus-silicon element: in an inert gas environment, fully mixing 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide with vinyl triethoxysilane in an organic solvent under the action of a catalyst, continuously stirring at 80 ℃, and reacting for 24 hours to obtain a phosphorus-silicon element-containing intermediate;

(2) preparing an amino-terminated phosphorus-silicon-boron multifunctional element flame retardant: and adding trimethylboroxine and 3-aminopropyltriethoxysilane into the phosphorus-silicon element-containing intermediate, continuing to react for 4-10 hours at 100 ℃, filtering or rotationally evaporating the reaction liquid, washing and drying the solid matters by absolute ethyl alcohol to obtain the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant.

In the step (1), the molar ratio of the 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide to the vinyl triethoxysilane to the catalyst to the organic solvent is 100:100:5: 1000-2000.

In the step (2), the molar ratio of the phosphorus-silicon element-containing intermediate to trimethylboroxine to 3-aminopropyltriethoxysilane is 1-4: 1-2: 1-4.

In the step (1), the inert gas is selected from any one of nitrogen, helium and argon.

In the step (1), the catalyst is 2, 2-azobisisobutyronitrile.

In the step (1), the organic solvent is diethylene glycol dimethyl ether.

In the step (2), the drying temperature is 60 ℃.

The amino-terminated phosphorus-silicon-boron multifunctional element flame retardant and the preparation method thereof provided by the invention have the following beneficial effects:

1. the flame retardant combines three flame retardant elements of phosphorus, silicon and boron into the same molecule, and adopts an amino end-capping mode, so that the multifunctional element can synergistically retard flame, thereby effectively improving the flame retardant effect and the comprehensive performance;

2. the flame retardant can play a flame retardant role in a gas phase and a condensed phase, and has good thermal stability and char forming capability;

3. the flame retardant does not contain halogen elements, and does not cause harm to the environment;

4. the flame retardant has active terminal amino groups, and can be chemically grafted with a base material through reactions such as crosslinking, condensation and the like, so that the polymer has an intrinsic flame retardant function.

5. The preparation method has the characteristics of mild reaction conditions, controllable reaction process, high yield and the like.

Drawings

FIG. 1 is an infrared spectrum of an amino-terminated phosphorus-silicon-boron multifunctional element flame retardant provided in example 1 of the present invention.

Detailed Description

The invention is described in detail below with reference to the figures and specific embodiments.

Example 1:

the preparation method of the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant provided by the embodiment comprises the following steps in sequence:

(1) preparing an intermediate containing phosphorus-silicon element: adding 100 parts of 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and 600 parts of diethylene glycol dimethyl ether into a dry three-neck round-bottom flask provided with a stirrer and a gas-guide tube, introducing nitrogen for protection, stirring and heating until the 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide is completely dissolved in the diethylene glycol dimethyl ether; then dissolving 100 parts of vinyl triethoxysilane and 5 parts of 2, 2-azobisisobutyronitrile into 400 parts of diethylene glycol dimethyl ether, stirring uniformly, dropwise adding into a round-bottom flask, and reacting at 80 ℃ for 24 hours to obtain a light yellow clear and transparent intermediate containing phosphorus-silicon elements;

(2) preparation of amino-terminated phosphorus-silicon-boron multifunctional element flame retardant: raising the temperature of the reaction system to 100 ℃, adding 100 parts of trioxyporoboroxine, dropwise adding 400 parts of 3-aminopropyltriethoxysilane after the trioxyporoboroxine is completely dissolved, and keeping the temperature at 100 ℃ for reacting for 6 hours; and then filtering or rotationally evaporating the reaction liquid, washing the solid matters by absolute ethyl alcohol, and then drying in an oven at the temperature of 60 ℃ to obtain a white solid powdery product, namely the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant.

Through tests, the chemical structural formula of the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant provided by the embodiment is as follows:

FIG. 1 is an infrared spectrum of the amino-terminated phosphorus-silicon-boron multifunctional flame retardant provided in this example.

As shown, the product FTIR: 1600cm^-1The left and right are skeleton vibration peak of benzene ring, 1211cm^-1And 917cm^-1Characteristic peaks of P ═ O and P-O-C respectively, 2900-3200 cm^-1is-NH₂1300-1500 cm of telescopic vibration peak^-1Is B-O absorption peak at 1138cm^-1Is the vibration absorption peak of Si-O-Si at about 685cm^-1、914cm^-1The deformation and stretching vibration peak of Si-O-B appear.

The yield of the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant is 41 percent. It was subjected to thermogravimetric analysis (air atmosphere, 20 ℃/min), T_5wt.％(mass loss 5%Temperature at (T) 187.4 ℃, T_10wt.％(temperature at 10% mass loss) was 351.9 ℃ and the char yield at 700 ℃ was 57.7%.

Example 2:

the preparation method of the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant provided by the embodiment comprises the following steps in sequence:

(1) preparing an intermediate containing phosphorus-silicon element: adding 100 parts of 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and 1600 parts of diethylene glycol dimethyl ether into a dry three-neck round-bottom flask provided with a stirrer and an air duct, introducing helium for protection, stirring and heating until the 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide is completely dissolved in the diethylene glycol dimethyl ether; then dissolving 100 parts of vinyl triethoxysilane and 5 parts of 2, 2-azobisisobutyronitrile into 400 parts of diethylene glycol dimethyl ether, stirring uniformly, dropwise adding into a round-bottom flask, and reacting at 80 ℃ for 24 hours to obtain a light yellow clear and transparent intermediate containing phosphorus-silicon elements;

(2) preparation of amino-terminated phosphorus-silicon-boron multifunctional element flame retardant: raising the temperature of the reaction system to 100 ℃, adding 200 parts of trioxygoroboroxine, dropwise adding 100 parts of 3-aminopropyltriethoxysilane after the trioxygoroxine is completely dissolved, and keeping the temperature at 100 ℃ for reacting for 6 hours; and then filtering or rotationally evaporating the reaction liquid, washing the solid matters by absolute ethyl alcohol, and then drying in an oven at the temperature of 60 ℃ to obtain a white solid powdery product, namely the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant.

The yield of the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant is 72 percent through tests. It was subjected to thermogravimetric analysis, T_5wt.％At 159.1 ℃ and T_10wt.％The char yield at 700 ℃ was 44.8% at 291.3 ℃.

Example 3:

the preparation method of the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant provided by the embodiment comprises the following steps in sequence:

(1) preparing an intermediate containing phosphorus-silicon element: adding 100 parts of 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and 1600 parts of diethylene glycol dimethyl ether into a dry three-neck round-bottom flask provided with a stirrer and an air duct, introducing helium for protection, stirring and heating until the 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide is completely dissolved in the diethylene glycol dimethyl ether; then dissolving 100 parts of vinyl triethoxysilane and 5 parts of 2, 2-azobisisobutyronitrile into 400 parts of diethylene glycol dimethyl ether, stirring uniformly, dropwise adding into a round-bottom flask, and reacting at 80 ℃ for 24 hours to obtain a light yellow clear and transparent intermediate containing phosphorus-silicon elements;

(2) preparation of amino-terminated phosphorus-silicon-boron multifunctional element flame retardant: raising the temperature of the reaction system to 100 ℃, adding 25 parts of trioxyporoboroxine, dropwise adding 25 parts of 3-aminopropyltriethoxysilane after the trioxyporoboroxine is completely dissolved, and keeping the temperature at 100 ℃ for reacting for 6 hours; and then filtering or rotationally evaporating the reaction liquid, washing the solid matters by absolute ethyl alcohol, and then drying in an oven at the temperature of 60 ℃ to obtain a white solid powdery product, namely the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant.

The yield of the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant is 45 percent through tests. It was subjected to thermogravimetric analysis, T_5wt.％At 140.2 ℃ and T_10wt.％The coke residue was 222.8 ℃ and the carbon residue rate was 45.7% at 700 ℃.

Example 4:

the preparation method of the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant provided by the embodiment comprises the following steps in sequence:

(1) preparing an intermediate containing phosphorus-silicon element: adding 100 parts of 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and 1600 parts of diethylene glycol dimethyl ether into a dry three-neck round-bottom flask provided with a stirrer and an air duct, introducing helium for protection, stirring and heating until the 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide is completely dissolved in the diethylene glycol dimethyl ether; then dissolving 100 parts of vinyl triethoxysilane and 5 parts of 2, 2-azobisisobutyronitrile into 400 parts of diethylene glycol dimethyl ether, stirring uniformly, dropwise adding into a round-bottom flask, and reacting at 80 ℃ for 24 hours to obtain a light yellow clear and transparent intermediate containing phosphorus-silicon elements;

(2) preparation of amino-terminated phosphorus-silicon-boron multifunctional element flame retardant: raising the temperature of the reaction system to 100 ℃, adding 133 parts of trioxygoroboroxine, dropwise adding 300 parts of 3-aminopropyltriethoxysilane after the trioxygoroxine is completely dissolved, and keeping the temperature at 100 ℃ for reacting for 6 hours; and then filtering or rotationally evaporating the reaction liquid, washing the solid matters by absolute ethyl alcohol, and then drying in an oven at the temperature of 60 ℃ to obtain a white solid powdery product, namely the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant.

The yield of the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant is tested to be 70%. It was subjected to thermogravimetric analysis, T_5wt.％At 184.6 ℃ and T_10wt.％The coke residue was 309.3 ℃ and the carbon residue rate was 60.4% at 700 ℃.

Example 5:

the preparation method of the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant provided by the embodiment comprises the following steps in sequence:

(1) preparing an intermediate containing phosphorus-silicon element: adding 100 parts of 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and 1600 parts of diethylene glycol dimethyl ether into a dry three-neck round-bottom flask provided with a stirrer and an air duct, introducing helium for protection, stirring and heating until the 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide is completely dissolved in the diethylene glycol dimethyl ether; then dissolving 100 parts of vinyl triethoxysilane and 5 parts of 2, 2-azobisisobutyronitrile into 400 parts of diethylene glycol dimethyl ether, stirring uniformly, dropwise adding into a round-bottom flask, and reacting at 80 ℃ for 24 hours to obtain a light yellow clear and transparent intermediate containing phosphorus-silicon elements;

(2) preparation of amino-terminated phosphorus-silicon-boron multifunctional element flame retardant: raising the temperature of the reaction system to 100 ℃, adding 167 parts of trioxygoroboroxine, dropwise adding 200 parts of 3-aminopropyltriethoxysilane after the trioxygoroxine is completely dissolved, and keeping the temperature at 100 ℃ for reacting for 6 hours; and then filtering or rotationally evaporating the reaction liquid, washing the solid matters by absolute ethyl alcohol, and then drying in an oven at the temperature of 60 ℃ to obtain a white solid powdery product, namely the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant.

Tested byThe yield of the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant is 75%. It was subjected to thermogravimetric analysis, T_5wt.％At 176.1 ℃ C, T_10wt.％The carbon residue rate was 214.8 ℃ and 700 ℃ was 60.1%.

Example 6:

(1) preparing an intermediate containing phosphorus-silicon element: adding 100 parts of 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and 1600 parts of diethylene glycol dimethyl ether into a dry three-neck round-bottom flask provided with a stirrer and an air duct, introducing helium for protection, stirring and heating until the 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide is completely dissolved in the diethylene glycol dimethyl ether; then dissolving 100 parts of vinyl triethoxysilane and 5 parts of 2, 2-azobisisobutyronitrile into 400 parts of diethylene glycol dimethyl ether, stirring uniformly, dropwise adding into a round-bottom flask, and reacting at 80 ℃ for 24 hours to obtain a light yellow clear and transparent intermediate containing phosphorus-silicon elements;

(2) preparation of amino-terminated phosphorus-silicon-boron multifunctional element flame retardant: raising the temperature of the reaction system to 100 ℃, adding 66.5 parts of trioxyporoboroxine, dropwise adding 100 parts of 3-aminopropyltriethoxysilane after the trioxyporoxine is completely dissolved, and keeping the temperature at 100 ℃ for reacting for 6 hours; and then filtering or rotationally evaporating the reaction liquid, washing the solid matters by absolute ethyl alcohol, and then drying in an oven at the temperature of 60 ℃ to obtain a white solid powdery product, namely the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant.

The yield of the amino-terminated phosphorus-silicon-boron multifunctional element flame retardant is 60 percent through testing. It was subjected to thermogravimetric analysis, T_5wt.％At 182.5 ℃ and T_10wt.％The coke residue was 209.0 ℃ and 55.2% at 700 ℃.

The amino-terminated phosphorus-silicon-boron multifunctional element flame retardant prepared in example 4 is applied to the flame-retardant modification of polymethacrylimide in a chemical grafting manner, and when the addition amount of the flame retardant is 15 wt.%, the flame-retardant polymethacrylimide can reach the grade of UL 94-V0. Table 1 shows the effect of the amount of flame retardant added on the flame retardancy of the substrate.

TABLE 1 influence of the amount of flame retardant added on the flame retardancy of the substrate