阅读说明：本技术 一种细粒度聚磷酸哌嗪阻燃剂及其制备方法和应用 (Fine-grained polyphosphoric acid piperazine flame retardant and preparation method and application thereof ) 是由 金凤 常智俐 田志雄 孟喜 叶丹阳 李俊彬 姚小龙 何伟 谌能办 李凤宇 于 2020-07-16 设计创作，主要内容包括：本发明公开了一种细粒度聚磷酸哌嗪阻燃剂,所述细粒度聚磷酸哌嗪阻燃剂粒径D50<20μm；本发明还公开了该细粒度聚磷酸哌嗪阻燃剂的制备方法,先将乙酸加入反应装置中,在搅拌条件下加入哌嗪,升温；加入多聚磷酸,搅拌,100～110℃下反应；冷却至室温,过滤、干燥即得到细粒度的聚磷酸哌嗪阻燃剂。该方法可直接制备粒径较细的聚磷酸哌嗪阻燃剂,产物干燥后无需经过粉碎工序即可使用,反应后过滤所得乙酸滤液无需处理可直接用于下次反应。(The invention discloses a fine-grained piperazine polyphosphate fire retardant, wherein the grain size D50 of the fine-grained piperazine polyphosphate fire retardant is less than 20 mu m; the invention also discloses a preparation method of the fine-grained piperazine polyphosphate fire retardant, which comprises the steps of adding acetic acid into a reaction device, adding piperazine under the stirring condition, and heating; adding polyphosphoric acid, stirring, and reacting at 100-110 ℃; and cooling to room temperature, filtering and drying to obtain the polyphosphoric acid piperazine flame retardant with fine particle size. The method can be used for directly preparing the piperazine polyphosphate flame retardant with a fine particle size, the product can be used without a crushing process after being dried, and the acetic acid filtrate obtained by filtering after the reaction can be directly used for the next reaction without being processed.)

1. The fine-grained piperazine polyphosphate flame retardant is characterized in that the grain size D50 of the fine-grained piperazine polyphosphate flame retardant is less than 20 microns.

2. A preparation method of a fine-grained piperazine polyphosphate flame retardant is characterized by comprising the following steps:

s1: firstly, adding acetic acid into a reaction device, adding piperazine under the stirring condition, and heating;

s2: adding polyphosphoric acid, stirring, and reacting at 100-110 ℃;

s3: and cooling to room temperature, filtering and drying to obtain the fine-grained polyphosphoric acid piperazine flame retardant.

3. The preparation method of the fine-grained piperazine polyphosphate flame retardant according to claim 2, wherein the mass ratio of piperazine to acetic acid in the step S1 is 1: 6-1: 15.

4. The preparation method of the fine-grained piperazine polyphosphate flame retardant according to claim 2, wherein the temperature is increased to 70-80 ℃ in the step S1.

5. The method for preparing the piperazine polyphosphate flame retardant according to claim 2, wherein the molar ratio of piperazine to polyphosphoric acid in the step S2 is 1.5:1-4: 1.

6. The preparation method of the fine-grained piperazine polyphosphate flame retardant according to claim 2, wherein the reaction time in the step S2 is 4-8 h.

7. The preparation method of the fine-grained piperazine polyphosphate flame retardant according to claim 2, wherein the particle size D50 of the prepared piperazine polyphosphate is less than 20 μm.

8. The preparation method of the fine-grained piperazine polyphosphate flame retardant according to claim 2, wherein an acetic acid filtrate obtained by filtering after the reaction is finished is reused as a reaction solvent for the reaction.

9. The application of the fine-grained piperazine polyphosphate flame retardant is characterized in that the fine-grained piperazine polyphosphate flame retardant disclosed in claim 1 is directly used for flame retardant modification of a high polymer material.

Technical Field

The invention relates to the technical field of flame retardants, and particularly relates to a fine-grained piperazine polyphosphate flame retardant and a preparation method and application thereof.

Background

With the rapid development of Chinese economy, the consumption of the flame retardant is greatly increased, and the piperazine phosphate (polyphosphoric acid piperazine) flame retardant has the characteristics of no halogen, low smoke, low toxicity, good thermal stability, excellent flame retardant property and the like, meets the requirement of green chemistry, and is rapidly developed in recent years.

Polyphosphoric acid piperazine with the phosphoric acid unit length of 2.2-10 is prepared by taking polyphosphoric acid and piperazine as raw materials at present, the particle size (D50) of the polyphosphoric acid piperazine is less than 30 mu m, and the reaction can be carried out in solvents such as alcohols, aromatic alkanes and halogenated alkanes; by the method for preparing polyphosphoric acid piperazine by directly taking polyphosphoric acid and piperazine as raw materials in a solvent-free state, the obtained product has a relatively thick particle size, a crushing process is needed, the reaction is carried out at a high temperature, and the risk of yellowing of the product exists; polyphosphoric acid and anhydrous piperazine are used as starting materials, the polyphosphoric acid piperazine with high polymerization degree is synthesized by reacting in a heating type kneading machine for 3 hours at 230 ℃, and the obtained product can be used for subsequent reaction after being crushed by a jet mill.

The particle size and the particle size distribution of the polyphosphoric acid piperazine are important technical indexes influencing the service performance of the polyphosphoric acid piperazine; piperazine polyphosphate is used as an inorganic additive flame retardant, has larger property difference with an organic polymer material matrix, and has poorer dispersibility; after the polyphosphoric acid piperazine with large particle size is blended into a matrix in a blending mode, the mechanical property or the processing property of the flame-retardant high polymer material can be reduced. The particle size of the piperazine polyphosphate flame retardant prepared by the prior art is relatively large, the prepared piperazine polyphosphate with the coarse particle size needs to be subjected to fine granularity in order to promote the dispersion of the piperazine polyphosphate, improve the compatibility of the piperazine polyphosphate flame retardant with a high polymer material and improve the flame retardant property, the piperazine polyphosphate with the coarse particle size can be used for a flame retardant high polymer material after being crushed, and the piperazine polyphosphate flame retardant has the defects of complex process, high cost, incapability of being directly used for the flame retardant high polymer material and the like.

Disclosure of Invention

In view of the above problems, a first object of the present invention is to provide a fine-grained piperazine polyphosphate flame retardant; the particle size D50 of the fine-grained piperazine polyphosphate flame retardant is less than 20 mu m, and the flame retardant is not required to be crushed and can be directly used for flame retardant modification of high polymer materials.

The second purpose of the invention is to provide a preparation method of the fine-grained piperazine polyphosphate fire retardant, which takes polyphosphoric acid and piperazine as raw materials and acetic acid (industrial grade) as a solvent to directly prepare the fine-grained piperazine polyphosphate fire retardant, does not need to be crushed, and can be directly used for flame retardant modification of high polymer materials; simple process, easy realization and low cost.

The third purpose of the invention is to provide the application of the fine-grained piperazine polyphosphate fire retardant, and the fine-grained piperazine polyphosphate fire retardant can be directly used for flame retardant modification of high polymer materials without being crushed.

The first technical scheme adopted by the invention is as follows: a fine-grained piperazine polyphosphate flame retardant, wherein the grain size D50 of the fine-grained piperazine polyphosphate flame retardant is less than 20 microns.

The second technical scheme adopted by the invention is as follows: a preparation method of a fine-grained piperazine polyphosphate flame retardant comprises the following steps:

s1: firstly, adding acetic acid into a reaction device, adding piperazine under the stirring condition, and heating;

s2: adding polyphosphoric acid, stirring, and reacting at 100-110 ℃;

s3: and cooling to room temperature, filtering and drying to obtain the fine-grained polyphosphoric acid piperazine flame retardant.

Preferably, the mass ratio of piperazine to acetic acid in the step S1 is 1: 6-1: 15.

Preferably, the temperature is increased to 70-80 ℃ in the step S1.

Preferably, the molar ratio of piperazine to polyphosphoric acid in step S2 is 1.5:1 to 4: 1.

Preferably, the reaction time in the step S2 is 4-8 h.

Preferably, the particle size D50 of the prepared piperazine polyphosphate is less than 20 μm.

Preferably, the acetic acid filtrate obtained after the completion of the reaction is filtered as a reaction solvent to be reused for the next reaction.

The third technical scheme adopted by the invention is as follows: the application of the fine-grained piperazine polyphosphate fire retardant is directly used for flame-retardant modification of a high polymer material.

The beneficial effects of the above technical scheme are that:

(1) the particle size D50 of the fine-grained piperazine polyphosphate flame retardant prepared by the invention is less than 20 mu m, and the flame retardant can be directly used for flame retardant modification of high polymer materials without being crushed.

(2) The method for preparing the fine-grained piperazine polyphosphate flame retardant disclosed by the invention directly prepares the fine-grained piperazine polyphosphate flame retardant by taking polyphosphoric acid and piperazine as raw materials and acetic acid (industrial grade) as a solvent, and has the advantages of no need of crushing, simple process, easiness in implementation and low cost.

(3) The acetic acid (industrial grade) solvent can be reused in the next reaction as a reaction solvent without other treatment after being filtered and recovered, so that the solvent recycling is realized, and the production cost is reduced.

(4) The invention does not need high-temperature condensation when preparing the fine-grained piperazine polyphosphate fire retardant, avoids the piperazine polyphosphate from yellowing, and has high whiteness of the prepared fine-grained piperazine polyphosphate fire retardant.

(5) The fine-grained piperazine polyphosphate flame retardant has good flame retardant performance and char forming performance, has good flame retardant effect in PP, PE, EP, PU and other materials, and is a halogen-free flame retardant with great market potential.

Drawings

FIG. 1 is a flow chart of a preparation process of a fine-grained piperazine polyphosphate flame retardant;

FIG. 2 is a particle size distribution diagram of a fine-grained piperazine polyphosphate flame retardant prepared in example 1 of the present invention;

FIG. 3 is a TG-DSC spectrum of a fine particle size piperazine polyphosphate flame retardant prepared in example 1 of the invention;

FIG. 4 is a particle size distribution diagram of a fine-grained piperazine polyphosphate flame retardant prepared in example 2 of the present invention;

FIG. 5 is a TG-DSC spectrum of a fine particle size piperazine polyphosphate flame retardant prepared in example 2 of the invention;

FIG. 6 is a particle size distribution diagram of a fine-grained piperazine polyphosphate flame retardant prepared in example 3 of the present invention;

FIG. 7 is a TG-DSC spectrum of fine particle size piperazine polyphosphate flame retardant prepared in example 3 of the invention.

Detailed Description

The present invention is further illustrated by the following specific examples, it should be noted that, for those skilled in the art, variations and modifications can be made without departing from the principle of the present invention, and these should also be construed as falling within the scope of the present invention.

The invention discloses a fine-grained piperazine polyphosphate flame retardant, wherein the grain size D50 of the fine-grained piperazine polyphosphate flame retardant is less than 20 mu m.

As shown in fig. 1, the fine-grained piperazine polyphosphate flame retardant is prepared by the following steps:

s1: adding acetic acid into a reaction device, adding piperazine under the stirring condition, and heating to 70-80 ℃; the mass ratio of piperazine to acetic acid is 1: 6-1: 15; the reaction device is a device capable of heating and refluxing, such as a reaction bottle, a reaction kettle and the like;

s2: adding polyphosphoric acid, stirring, and reacting for 4-8 h at 100-110 ℃; the molar ratio of the piperazine to the polyphosphoric acid is 1.5:1-4: 1;

s3: cooling to room temperature, filtering and drying to obtain the polyphosphoric acid piperazine flame retardant with fine particle size; the particle size D50 of the prepared fine-grained piperazine polyphosphate flame retardant is less than 20 mu m. After the reaction is finished, filtering the obtained acetic acid filtrate as a reaction solvent to be reused in the next reaction.