阅读说明：本技术 一种聚丙烯阻燃母粒、其制备方法和阻燃聚丙烯 (Polypropylene flame-retardant master batch, preparation method thereof and flame-retardant polypropylene ) 是由 袁文博 柳金章 赵明雷 刘振振 张晓通 郎贤忠 徐宾 王耀伟 栾波 于 2021-11-26 设计创作，主要内容包括：本发明提供了一聚丙烯阻燃母粒的制备方法,包括：A)磷酸和季戊四醇加热反应,得到季戊四醇磷酸酯；B)所述季戊四醇磷酸酯和三聚氰胺混合密炼进行成盐反应,得到阻燃剂；C)阻燃剂与聚丙烯、抗氧剂和润滑剂混合、密炼、挤出、造粒即得聚丙烯阻燃母粒。本发明在季戊四醇磷酸酯三聚氰胺盐的合成过程中加入少量聚丙烯,通过密炼机的混炼、挤出造粒制备了集酸源、碳源、气源于一体的聚丙烯无卤阻燃母粒。本发明产品在阻燃剂反应合成过程中直接制备,减少了粉尘污染,减少了粉体团聚,提高了阻燃剂在基材中的分散程度。同时母粒中阻燃剂浓度提高到了90％～95％,降低了母粒的生产成本。本发明中制备的阻燃聚丙烯具有很好的耐水性能。(The invention provides a preparation method of polypropylene flame-retardant master batch, which comprises the following steps: A) heating phosphoric acid and pentaerythritol to react to obtain pentaerythritol phosphate; B) mixing and banburying pentaerythritol phosphate and melamine for salt forming reaction to obtain a flame retardant; C) and mixing the flame retardant with polypropylene, an antioxidant and a lubricant, banburying, extruding and granulating to obtain the polypropylene flame-retardant master batch. In the invention, a small amount of polypropylene is added in the synthesis process of pentaerythritol phosphate melamine salt, and the polypropylene halogen-free flame-retardant master batch integrating an acid source, a carbon source and a gas source is prepared by mixing, extruding and granulating through an internal mixer. The product of the invention is directly prepared in the reaction synthesis process of the flame retardant, thereby reducing dust pollution, reducing powder agglomeration and improving the dispersion degree of the flame retardant in the base material. Meanwhile, the concentration of the flame retardant in the master batch is increased to 90-95%, and the production cost of the master batch is reduced. The flame-retardant polypropylene prepared by the method has good water resistance.)

1. The preparation method of the polypropylene flame-retardant master batch is characterized by comprising the following steps:

A) heating phosphoric acid and pentaerythritol to react to obtain pentaerythritol phosphate;

B) mixing and banburying pentaerythritol phosphate and melamine for salt forming reaction to obtain a flame retardant;

C) and mixing the flame retardant with polypropylene, an antioxidant and a lubricant, banburying, extruding and granulating to obtain the polypropylene flame-retardant master batch.

2. The method of claim 1, wherein the molar ratio of phosphoric acid to pentaerythritol is 1.95:1 to 2.05: 1; the molar ratio of the melamine to the pentaerythritol is 1.95: 1-2.05: 1.

3. The method according to claim 1, wherein the flame retardant accounts for 90-95% of the polypropylene flame-retardant master batch by mass.

4. The method of claim 1, wherein the antioxidant is one or more of antioxidant 1010, antioxidant 168, antioxidant 245, antioxidant 1098, DLTP or DSTP; the lubricant is one or more of EBS, montan wax, stearic acid or zinc stearate.

5. The method according to claim 1, wherein the temperature of the heating reaction in the step A) is 80-100 ℃; the time is 4-8 h.

6. The method according to claim 1, wherein the temperature of the salt forming reaction in step B) is 180-220 ℃.

7. The polypropylene flame-retardant master batch is characterized by being prepared by the preparation method of any one of claims 1 to 7.

8. The flame-retardant polypropylene is characterized by comprising the polypropylene flame-retardant master batch prepared by the preparation method of any one of claims 1 to 7, polypropylene and an auxiliary agent.

9. The flame retardant polypropylene according to claim 8, wherein the polypropylene flame retardant masterbatch is added in an amount of 14 wt% to 18 wt%; the auxiliary agent is calcium stearate and nano montmorillonite; the addition amount of the calcium stearate and the nano montmorillonite is 0.5 to 1.0 weight percent.

Technical Field

The invention relates to the field of preparation of flame-retardant master batch materials, in particular to a polypropylene flame-retardant master batch, a preparation method thereof and flame-retardant polypropylene.

Background

Polypropylene (PP) has been widely used in daily life of people as a general plastic due to its excellent thermal stability, chemical stability, electrical insulation property, weather resistance, and the like. The processing can be carried out by injection molding, extrusion molding, blow molding and the like. The method is widely applied to the fields of household appliances, automobiles, intelligent houses, building materials and the like.

But the PP oxygen index is only about 18 percent, and belongs to a combustible material. In the combustion process, a large amount of heat and smoke are released, and the molten drops are accompanied, so that surrounding articles are easily ignited, and the life and property are greatly damaged.

In order to avoid fire, flame retardancy is required in many fields. The high crystallinity and flammability of PP makes it particularly difficult to achieve high flame retardant ratings. Therefore, it is necessary to conduct flame retardant studies on PP.

The flame retardant used for PP comprises halogen flame retardant, inorganic flame retardant, intumescent flame retardant and the like. The halogen flame retardant has excellent flame retardant effect, but generates a large amount of smoke and corrosive gas in the combustion process, thereby being harmful to the health of human bodies. Inorganic metal hydroxide is environment-friendly and toxic, but has low flame retardant efficiency, requires a higher addition amount to achieve the flame retardant effect, and seriously influences the mechanical properties of the material. The halogen-free phosphorus-nitrogen intumescent flame retardant has low smoke, low toxicity, environmental protection and high efficiency, and is an ideal PP flame retardant. However, the existing intumescent flame retardant still has the defects of poor water resistance and great influence on mechanical properties. In addition, most of the intumescent flame retardants for polypropylene are powder, so a great amount of dust pollution is generated in the processes of proportioning, mixing and production, the environment is worsened, the human health is harmed, and the screw is abraded.

Therefore, it is very necessary to provide a polypropylene flame-retardant master batch with high flame-retardant efficiency and good water resistance.

Disclosure of Invention

In view of the above, the technical problem to be solved by the invention is to provide a polypropylene flame-retardant master batch, and the flame-retardant polypropylene prepared from the polypropylene flame-retardant master batch has high flame-retardant efficiency and good water resistance.

The invention provides a preparation method of polypropylene flame-retardant master batch, which comprises the following steps:

A) heating phosphoric acid and pentaerythritol to react to obtain pentaerythritol phosphate;

B) mixing and banburying pentaerythritol phosphate and melamine for salt forming reaction to obtain a flame retardant;

C) and mixing the flame retardant with polypropylene, an antioxidant and a lubricant, banburying, extruding and granulating to obtain the polypropylene flame-retardant master batch.

Preferably, the molar ratio of the phosphoric acid to the pentaerythritol is 1.95: 1-2.05: 1; the molar ratio of the melamine to the pentaerythritol is 1.95: 1-2.05: 1.

Preferably, the flame retardant accounts for 90-95% of the polypropylene flame-retardant master batch by mass.

Preferably, the antioxidant is one or more of antioxidant 1010, antioxidant 168, antioxidant 245, antioxidant 1098, DLTP or DSTP; the lubricant is one or more of EBS, montan wax, stearic acid or zinc stearate.

Preferably, the temperature of the heating reaction in the step A) is 80-100 ℃; the time is 4-8 h.

Preferably, the temperature of the salt forming reaction in the step B) is 180-220 ℃.

The invention provides a polypropylene flame-retardant master batch which is prepared by the preparation method of any one of the technical schemes.

The invention provides an application of a halogen-free flame-retardant master batch, which comprises the polypropylene flame-retardant master batch prepared by the preparation method in any one of the technical schemes, polypropylene and an auxiliary agent.

Compared with the prior art, the invention provides a preparation method of polypropylene flame-retardant master batch, which comprises the following steps: A) heating phosphoric acid and pentaerythritol to react to obtain pentaerythritol phosphate; B) mixing and banburying pentaerythritol phosphate and melamine for salt forming reaction to obtain a flame retardant; C) and mixing the flame retardant with polypropylene, an antioxidant and a lubricant, banburying, extruding and granulating to obtain the polypropylene flame-retardant master batch. In the invention, a small amount of polypropylene is added in the synthesis process of pentaerythritol phosphate melamine salt, and the polypropylene halogen-free flame-retardant master batch integrating an acid source, a carbon source and a gas source is prepared by mixing, extruding and granulating through an internal mixer. The product of the invention is directly prepared in the reaction synthesis process of the flame retardant, thereby reducing dust pollution, reducing powder agglomeration and improving the dispersion degree of the flame retardant in the base material. Meanwhile, the concentration of the flame retardant in the master batch is increased to 90-95%, and the production cost of the master batch is reduced. The flame retardant integrates an acid source, a carbon source and a gas source, has high flame retardant efficiency, and can reach UL 94V-0 grade by adding 14-18 wt% of the flame retardant master batch. Meanwhile, the water solubility of the flame retardant is low, and the prepared flame-retardant polypropylene has good water resistance and completely passes the water resistance test of UL 746C.

Detailed Description

The invention provides a polypropylene flame-retardant master batch, a preparation method thereof and flame-retardant polypropylene, and a person skilled in the art can use the contents for reference and appropriately improve process parameters to realize the flame-retardant master batch. It is expressly intended that all such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the scope of the invention. While the methods and applications of this invention have been described in terms of preferred embodiments, it will be apparent to those of ordinary skill in the art that variations and modifications in the methods and applications described herein, as well as other suitable variations and combinations, may be made to implement and use the techniques of this invention without departing from the spirit and scope of the invention.

The invention provides a preparation method of polypropylene flame-retardant master batch, which comprises the following steps:

A) heating phosphoric acid and pentaerythritol to react to obtain pentaerythritol phosphate;

B) mixing and banburying pentaerythritol phosphate and melamine for salt forming reaction to obtain a flame retardant;

C) and mixing the flame retardant with polypropylene, an antioxidant and a lubricant, banburying, extruding and granulating to obtain the polypropylene flame-retardant master batch.

The preparation method of the polypropylene flame-retardant master batch provided by the invention comprises the following step of heating phosphoric acid and pentaerythritol to react to obtain pentaerythritol phosphate.

The above reaction of the present invention is preferably carried out in a reactor, and the present invention is not limited to a specific reactor, and is well known to those skilled in the art.

The molar ratio of phosphoric acid to pentaerythritol is preferably 1.95: 1-2.05: 1; wherein the temperature of the heating reaction is preferably 80-100 ℃; more preferably 80-95 ℃; the time is preferably 4-8 h; more preferably 4 to 7 hours.

And mixing and banburying the pentaerythritol phosphate and melamine for salt forming reaction to obtain the flame retardant.

Namely: pentaerythritol phosphate and melamine are added into a continuous banburying granulator and are uniformly stirred to obtain pentaerythritol phosphate melamine salt, namely the flame retardant of the invention.

The molar ratio of melamine to pentaerythritol is preferably 1.95: 1-2.05: 1.

The preferable temperature of the salt forming reaction is 180-220 ℃.

Namely: and carrying out a salt forming reaction on the generated pentaerythritol phosphate and melamine at the temperature of 180-200 ℃ to generate pentaerythritol phosphate melamine salt integrating an acid source, a carbon source and a gas source.

The flame retardant is mixed with polypropylene, an antioxidant and a lubricant, and then banburying, extrusion and granulation are carried out to obtain the polypropylene flame-retardant master batch.

Adding polypropylene, an antioxidant and a lubricant into an internal mixer, mixing uniformly and fully, and granulating through an extruder connected with the internal mixer in series to prepare the polypropylene flame-retardant master batch integrating an acid source, a carbon source and a gas source.

The added polypropylene plays a role of a carrier, and the pentaerythritol phosphate melamine salt can be uniformly loaded on the polypropylene, so that the agglomeration of the flame retardant is reduced, and the flame retardant efficiency is improved.

The extruder is a single-screw extruder, and in the single-screw extrusion granulation process, reactants fully react and are uniformly mixed with polypropylene to prepare the polypropylene flame-retardant master batch.

The mass percentage of the flame retardant in the polypropylene flame-retardant master batch is preferably 90-95%.

The mass ratio of the antioxidant to the polypropylene is 0.3: 100-0.8: 100, the mass ratio of the lubricant to the polypropylene is 0.1: 100-0.5: 100.

the antioxidant is one or more of antioxidant 1010, antioxidant 168, antioxidant 245, antioxidant 1098, DLTP or DSTP; the lubricant is one or more of EBS, montan wax, stearic acid or zinc stearate.

The invention firstly generates pentaerythritol phosphate (intermediate) by reacting phosphoric acid with pentaerythritol, uniformly stirs the intermediate and melamine by virtue of the strong stirring function of an internal mixer, then blends and mixes the intermediate and PP, and extrudes and granulates to prepare the special flame-retardant master batch for polypropylene.

The invention provides a polypropylene flame-retardant master batch which is prepared by the preparation method of any one of the technical schemes.

The polypropylene flame-retardant master batch is directly prepared in the reaction synthesis process of the flame retardant, so that the dust pollution is reduced.

The polypropylene is added in the salifying reaction process of the flame retardant, so that the agglomeration of the flame retardant can be reduced, the flame retardant can be better dispersed in the polypropylene, meanwhile, the concentration of the flame retardant in the master batch is improved to 90-95%, and the production cost of the master batch is reduced.

The flame retardant integrates an acid source, a carbon source and a gas source, has high flame retardant efficiency, and can reach UL 94V-0 grade by adding 14-18 wt% of the flame retardant master batch. Meanwhile, the water solubility of the flame retardant is low, and the prepared flame-retardant polypropylene has good water resistance and can completely pass the water resistance test of UL 746C.

The present invention has been described clearly for the above specific preparation method, and is not described herein again.

The invention provides flame-retardant polypropylene, which comprises the polypropylene flame-retardant master batch prepared by the preparation method in any one of the technical schemes, polypropylene and an auxiliary agent.

The addition amount of the polypropylene flame-retardant master batch in the flame-retardant polypropylene is 14-18 wt%; the auxiliary agent is calcium stearate and nano montmorillonite.

Wherein the addition amount of the polypropylene is 80-85 wt%. The addition amount of the auxiliary agent is 1-2 wt%.

The invention also provides a preparation method of the flame-retardant polypropylene, which comprises the following steps:

and mixing, extruding and granulating the polypropylene flame-retardant master batch, the polypropylene and the auxiliary agent to obtain the flame-retardant polypropylene.

The invention provides an application of halogen-free flame-retardant PP master batch as a flame retardant of flame-retardant polypropylene, wherein the addition amount of the halogen-free flame-retardant PP master batch accounts for 14-18% of the total mass of the flame-retardant modified polypropylene. The application of the halogen-free flame-retardant PP master batch is specifically to perform mixing, extrusion and granulation on the polypropylene and the flame-retardant master batch in the mass fraction, injection molding of a flame-retardant and mechanical sample strip, and performing flame-retardant, mechanical and water-resistant performance tests.

Wherein the extrusion granulation temperature is preferably 190 ℃ to 210 ℃.

The invention provides a preparation method of polypropylene flame-retardant master batch, which comprises the following steps: A) heating phosphoric acid and pentaerythritol to react to obtain pentaerythritol phosphate; B) mixing and banburying pentaerythritol phosphate and melamine for salt forming reaction to obtain a flame retardant; C) and mixing the flame retardant with polypropylene, an antioxidant and a lubricant, banburying, extruding and granulating to obtain the polypropylene flame-retardant master batch. In the invention, a small amount of polypropylene is added in the synthesis process of pentaerythritol phosphate melamine salt, and the polypropylene halogen-free flame-retardant master batch integrating an acid source, a carbon source and a gas source is prepared by mixing, extruding and granulating through an internal mixer. The product of the invention is directly prepared in the reaction synthesis process of the flame retardant, thereby reducing dust pollution, reducing powder agglomeration and improving the dispersion degree of the flame retardant in the base material. Meanwhile, the concentration of the flame retardant in the master batch is increased to 90-95%, and the production cost of the master batch is reduced.

In order to further illustrate the present invention, the following describes the polypropylene flame retardant masterbatch, the preparation method thereof and the flame retardant polypropylene in detail with reference to the examples.

Example 1

3.4kg of pentaerythritol and 6.1kg of phosphoric acid are added into a 20L reactor, and the pentaerythritol phosphate is obtained after the reaction for 4 hours under the heat preservation at the temperature of 80 ℃. The pentaerythritol phosphate and 6.3kg of melamine were added to a continuous internal mixer and internally mixed at 90 ℃ for 20 minutes to allow the reactants to be fully mixed and to undergo a preliminary salt-forming reaction. Adding 1.75kg of polypropylene, 0.03kg of antioxidant 1010 and 0.02kg of antioxidant 168 into an internal mixer, internally mixing and granulating by an extruder with the internal mixer connected in series to prepare the polypropylene flame-retardant master batch.

Uniformly mixing 18 parts by mass of polypropylene flame-retardant master batch with 81 parts by weight of polypropylene K7726 and 1 part by weight of auxiliary agent, and mixing and granulating by using a double-screw extruder, wherein the extrusion temperature is set to 190-210 ℃.

Example 2

3.4kg of pentaerythritol and 6.1kg of phosphoric acid are added into a 20L reactor, and the pentaerythritol phosphate is obtained after the reaction for 4 hours under the heat preservation at the temperature of 80 ℃. The pentaerythritol phosphate and 6.3kg of melamine were added to a continuous internal mixer and internally mixed at 80 ℃ for 30 minutes to fully mix the reactants and carry out a preliminary salt-forming reaction. Adding 1.75kg of polypropylene, 0.03kg of antioxidant 1010 and 0.02kg of antioxidant 168 into an internal mixer, internally mixing and granulating by an extruder with the internal mixer connected in series to prepare the polypropylene flame-retardant master batch.

Uniformly mixing 18 parts by mass of polypropylene flame-retardant master batch with 81 parts by weight of polypropylene K7726 and 1 part by weight of auxiliary agent, and mixing and granulating by using a double-screw extruder, wherein the extrusion temperature is set to 190-210 ℃.

Example 3

Adding 3.4kg of pentaerythritol and 6.3kg of phosphoric acid into a 20L reactor, and reacting for 4 hours at the temperature of 80 ℃ to obtain pentaerythritol phosphate. The pentaerythritol phosphate and 6.5kg of melamine were added to a continuous internal mixer and internally mixed at 90 ℃ for 20 minutes to fully mix the reactants and carry out a preliminary salt-forming reaction. Adding 1.8kg of polypropylene, 0.03kg of antioxidant 1010 and 0.02kg of antioxidant 168 into an internal mixer, internally mixing and granulating by an extruder with the internal mixer connected in series to prepare the polypropylene flame-retardant master batch.

Uniformly mixing 18 parts by mass of polypropylene flame-retardant master batch with 81 parts by weight of polypropylene K7726 and 1 part by weight of auxiliary agent, and mixing and granulating by using a double-screw extruder, wherein the extrusion temperature is set to 190-210 ℃.

Example 4

Adding 3.4kg of pentaerythritol and 6.3kg of phosphoric acid into a 20L reactor, and reacting for 4 hours at the temperature of 80 ℃ to obtain pentaerythritol phosphate. The pentaerythritol phosphate and 6.5kg of melamine were added to a continuous internal mixer and internally mixed at 90 ℃ for 20 minutes to fully mix the reactants and carry out a preliminary salt-forming reaction. Adding 1.5kg of polypropylene, 0.03kg of antioxidant 1010 and 0.02kg of antioxidant 168 into an internal mixer, internally mixing and granulating by an extruder with the internal mixer connected in series to prepare the polypropylene flame-retardant master batch.

Uniformly mixing 16 parts by mass of polypropylene flame-retardant master batch with 83 parts by weight of polypropylene K7726 and 1 part by weight of auxiliary agent, and mixing and granulating by using a double-screw extruder, wherein the extrusion temperature is set to 190-210 ℃.

Example 5

Adding 3.4kg of pentaerythritol and 6.3kg of phosphoric acid into a 20L reactor, and reacting for 4 hours at the temperature of 80 ℃ to obtain pentaerythritol phosphate. The pentaerythritol phosphate and 6.5kg of melamine were added to a continuous internal mixer and internally mixed at 90 ℃ for 20 minutes to fully mix the reactants and carry out a preliminary salt-forming reaction. Adding 0.9kg of polypropylene, 0.03kg of antioxidant 1010 and 0.02kg of antioxidant 168 into an internal mixer, internally mixing and granulating by an extruder with the internal mixer connected in series to obtain the polypropylene flame-retardant master batch.

Uniformly mixing 14 parts by weight of polypropylene flame-retardant master batch, 85 parts by weight of polypropylene K7726 and 1 part by weight of auxiliary agent, and mixing and granulating by using a double-screw extruder, wherein the extrusion temperature is set to 190-210 ℃.

Comparative example 1

A commercially available flame retardant FR201 (ammonium polyphosphate series PP halogen-free flame retardant) was selected.

Comparative example 2

A commercially available flame retardant FR601 (piperazine pyrophosphate series PP halogen-free flame retardant) was selected.

Application examples

The flame-retardant polypropylene was prepared by mixing the flame-retardant master batches of the above examples and comparative examples with polypropylene (brand K7726) according to the formulation of table 1, and the performance test results are shown in table 2.

TABLE 1

TABLE 2

The tests show that when 14-18% of flame-retardant master batch is added, the polypropylene (K7726) can achieve 1.5mm V-0 level flame retardance and can pass the water resistance test of UL 746C. Compared with comparative examples 1 and 2, the PP flame-retardant master batch prepared by the invention has high flame retardant property, good water resistance and excellent mechanical property.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.