阅读说明：本技术 一种阻燃型pp塑料颗粒及其制备方法 (Flame-retardant PP plastic particle and preparation method thereof ) 是由 唐鹏 于 2020-05-28 设计创作，主要内容包括：本发明公开了一种阻燃型PP塑料颗粒,由如下重量份原料制成：PP树脂70-80份、阻燃剂20-25份、滑石粉20-22份、润滑分散剂3-4份、热稳定剂4-5份、抗氧剂3-4份；所述阻燃型PP塑料颗粒的制备方法如下：第一步、混料；第二步、将第一步中的混合料继续升高温度至100-110℃,继续在800-1000r/min转速下搅拌5-6min,自然冷却至室温后,得到预混物；第三步、将预混物置于平行双螺杆挤出机中经熔融挤、造粒,得到阻燃型PP塑料颗粒。本发明采用的阻燃剂不仅具有有机氮磷阻燃剂的高阻燃性和良好的相容性,而且具有无机镁阻燃剂无毒、抑烟、稳定的绿色优点,通过合理的配方及制备工艺,制备出具有优异的阻燃效果的PP塑料颗粒。(The invention discloses flame-retardant PP plastic particles which are prepared from the following raw materials in parts by weight: 70-80 parts of PP resin, 20-25 parts of flame retardant, 20-22 parts of talcum powder, 3-4 parts of lubricating dispersant, 4-5 parts of heat stabilizer and 3-4 parts of antioxidant; the preparation method of the flame-retardant PP plastic particle comprises the following steps: firstly, mixing materials; step two, continuously raising the temperature of the mixture obtained in the step one to 100-110 ℃, continuously stirring for 5-6min at the rotating speed of 800-1000r/min, and naturally cooling to room temperature to obtain a premix; and thirdly, placing the premix in a parallel double-screw extruder, and performing melt extrusion and granulation to obtain the flame-retardant PP plastic particles. The flame retardant adopted by the invention not only has high flame retardance and good compatibility of an organic nitrogen-phosphorus flame retardant, but also has the advantages of non-toxicity, smoke suppression and stable green of an inorganic magnesium flame retardant, and PP plastic particles with excellent flame retardant effect are prepared by a reasonable formula and a preparation process.)

1. The flame-retardant PP plastic particle is characterized by being prepared from the following raw materials in parts by weight: 70-80 parts of PP resin, 20-25 parts of flame retardant, 20-22 parts of talcum powder, 3-4 parts of lubricating dispersant, 4-5 parts of heat stabilizer and 3-4 parts of antioxidant;

The flame-retardant PP plastic particle is prepared by the following steps:

Firstly, weighing the raw materials according to the parts by weight, putting the raw materials into a high-speed mixer together, stirring and mixing, wherein the mixing temperature is 55-60 ℃, the rotating speed is 800-1000r/min, and the mixing time is 8-10min to obtain a mixture;

Step two, continuously raising the temperature of the mixture obtained in the step one to 100-110 ℃, continuously stirring for 5-6min at the rotating speed of 800-1000r/min, and naturally cooling to room temperature to obtain a premix;

And thirdly, placing the premix in a parallel double-screw extruder, and performing melt extrusion and granulation to obtain the flame-retardant PP plastic particles.

2. The flame-retardant PP plastic particle according to claim 1, wherein the lubricating dispersant is one or a mixture of ethylene bis-fatty acid amide and stearic acid in any ratio.

3. The flame retardant PP plastic particle of claim 1, wherein the heat stabilizer is an organic tin stabilizer or a calcium zinc composite stabilizer.

4. The flame retardant PP plastic particle according to claim 1, wherein the antioxidant is a mixture of phosphite antioxidant 168 and hindered phenol antioxidant 1010 in a mass ratio of 1: 2.

5. The flame retardant PP plastic particle according to claim 1, wherein the flame retardant is prepared by the following steps:

(1) Adding 3.0kg of hexamethylol melamine, 5.0kg of phosphorous acid and 3.0kg of hydrochloric acid into a reaction kettle provided with a reflux condenser tube, stirring for 70-90min at normal temperature, slowly dropwise adding 7.0kg of hydrochloric acid into the reaction kettle by using a constant-pressure titration funnel, controlling the dropping speed to ensure that the dropwise adding of the hydrochloric acid is finished within 2-3h, then continuously stirring for 110-120min, slowly increasing the temperature in the reaction kettle to 95-98 ℃, carrying out reflux stirring reaction for 8h, cooling, standing the reaction solution, then filtering and distilling to obtain an intermediate;

(2) Adding 2.2kg of magnesium carbonate and 1.8kg of intermediate prepared in the step (1) into a reaction kettle, stirring to completely dissolve the magnesium carbonate, adding ammonia water to adjust the pH value of a reaction solution to 8.0, heating the system to 98-100 ℃, carrying out reflux reaction for 10-12h, filtering, distilling, standing for 10-12h, filtering again, and placing a filter cake in a vacuum drying oven at 60 ℃ for drying for 7-8h to prepare the flame retardant.

6. The preparation method of the flame retardant PP plastic particle according to claim 1, wherein the method comprises the following steps:

Firstly, weighing the raw materials according to the parts by weight, putting the raw materials into a high-speed mixer together, stirring and mixing, wherein the mixing temperature is 55-60 ℃, the rotating speed is 800-1000r/min, and the mixing time is 8-10min to obtain a mixture;

Step two, continuously raising the temperature of the mixture obtained in the step one to 100-110 ℃, continuously stirring for 5-6min at the rotating speed of 800-1000r/min, and naturally cooling to room temperature to obtain a premix;

And thirdly, placing the premix in a parallel double-screw extruder, and performing melt extrusion and granulation to obtain the flame-retardant PP plastic particles.

7. The method for preparing flame-retardant PP plastic granules according to claim 6, wherein in the third step, the extrusion parameters are as follows: 170-180 ℃ in the first area, 180-190 ℃ in the second area, 190-200 ℃ in the third area, 190-210 ℃ in the fourth area, 350-400r/min of screw rotation speed, 20-25Hz of feeding frequency, 3.0-4.0MPa of melt pressure and-0.03-0.06 MPa of vacuum degree.

Technical Field

The invention belongs to the technical field of PP (polypropylene) processing, and particularly relates to flame-retardant PP plastic particles and a preparation method thereof.

Background

The polypropylene (PP) is one of five general-purpose plastics, and the density is 0.90g/cm ³Is the second light polymer material (only larger than polymethylpentene, with a density of 0.85 g/cm) ³). Because of its utensil The plastic has the characteristics of good performance, small specific gravity, easy molding and processing and the like, and is widely applied to the automobile industry, the household appliances, the electronic instrument industry and the textile industry. However, since the limited oxygen index (OI value) of PP resin is very low, only 18, which is a flammable material, it cannot meet the use requirements of specific material in the field of fire protection, and thus it is limited to a certain extent when applied to the fields of household appliances, electronic instrument industry, textile industry, etc., and therefore, it is very important to improve the flame retardant property of PP plastics.

The Chinese patent with the patent number of CN201910646769.3 discloses a flame-retardant PP material and a preparation method thereof, wherein the flame-retardant PP material comprises the following components in percentage by mass: 48-63 parts of 64M40TPP resin, 48-63 parts of T30SPP resin, 20-35 parts of flame retardant, 15-17 parts of antioxidant, 8-12 parts of cross-linking agent, 12-14 parts of talcum powder, 5-8 parts of light calcium carbonate, 10-12 parts of modified additive and 10-12 parts of expandable graphite, wherein the flame retardant is any one of brominated flame retardant, phosphorus-nitrogen flame retardant or phosphorus flame retardant.

Disclosure of Invention

The invention aims to provide flame-retardant PP plastic particles and a preparation method thereof, wherein a self-made flame retardant is blended with PP resin, and the self-made flame retardant is an organic-inorganic hybrid phosphorus-nitrogen-magnesium flame retardant, not only has high flame retardance and good compatibility of an organic nitrogen-phosphorus flame retardant, but also has the advantages of non-toxicity, smoke suppression and stable green of an inorganic magnesium flame retardant, thereby avoiding the defects of the traditional flame retardant and also giving full play to the advantages of two flame retardants; the flame retardant has good thermal stability and good compatibility with a PP matrix, and can reduce the release of harmful corrosive gas and prolong the flame retardant time on the basis of improving the flame retardant effect and stability; the phosphorus-nitrogen flame retardant component contained in the flame retardant coating can play multiple flame retardant effects on the basis of gas phase and char formation, the char formation is promoted on the surface of the material, the carbon layer formed on the surface protects the lower-layer material, the decomposition of substances is delayed, a good flame retardant effect is achieved, and the PP plastic particles have excellent flame retardant performance.

The purpose of the invention can be realized by the following technical scheme:

The flame-retardant PP plastic particle is prepared from the following raw materials in parts by weight: 70-80 parts of PP resin, 20-25 parts of flame retardant, 20-22 parts of talcum powder, 3-4 parts of lubricating dispersant, 4-5 parts of heat stabilizer and 3-4 parts of antioxidant;

The flame-retardant PP plastic particle is prepared by the following steps:

Firstly, weighing the raw materials according to the parts by weight, putting the raw materials into a high-speed mixer together, stirring and mixing, wherein the mixing temperature is 55-60 ℃, the rotating speed is 800-1000r/min, and the mixing time is 8-10min to obtain a mixture;

Step two, continuously raising the temperature of the mixture obtained in the step one to 100-110 ℃, continuously stirring for 5-6min at the rotating speed of 800-1000r/min, and naturally cooling to room temperature to obtain a premix;

And thirdly, placing the premix in a parallel double-screw extruder, and performing melt extrusion and granulation to obtain the flame-retardant PP plastic particles.

Further, the lubricating dispersant is one or a compound of ethylene bis-fatty acid amide and stearic acid in any ratio.

Further, the heat stabilizer is an organic tin stabilizer or a calcium-zinc composite stabilizer.

Further, the antioxidant is a compound of phosphite antioxidant 168 and hindered phenol antioxidant 1010 which are mixed according to the mass ratio of 1: 2.

Further, the flame retardant is prepared by the following method:

(1) Adding 3.0kg of hexamethylol melamine, 5.0kg of phosphorous acid and 3.0kg of hydrochloric acid into a reaction kettle provided with a reflux condenser tube, stirring for 70-90min at normal temperature, slowly dropwise adding 7.0kg of hydrochloric acid into the reaction kettle by using a constant-pressure titration funnel, controlling the dropping speed to ensure that the dropwise adding of the hydrochloric acid is finished within 2-3h, then continuously stirring for 110-120min, slowly increasing the temperature in the reaction kettle to 95-98 ℃, carrying out reflux stirring reaction for 8h, cooling, standing the reaction solution, then filtering and distilling to obtain an intermediate;

(2) Adding 2.2kg of magnesium carbonate and 1.8kg of intermediate prepared in the step (1) into a reaction kettle, stirring to completely dissolve the magnesium carbonate, adding ammonia water to adjust the pH value of a reaction solution to 8.0, heating the system to 98-100 ℃, carrying out reflux reaction for 10-12h, filtering, distilling, standing for 10-12h, filtering again, and placing a filter cake in a vacuum drying oven at 60 ℃ for drying for 7-8h to prepare the flame retardant.

The preparation method of the flame-retardant PP plastic particles comprises the following steps:

Firstly, weighing the raw materials according to the parts by weight, putting the raw materials into a high-speed mixer together, stirring and mixing, wherein the mixing temperature is 55-60 ℃, the rotating speed is 800-1000r/min, and the mixing time is 8-10min to obtain a mixture;

Step two, continuously raising the temperature of the mixture obtained in the step one to 100-110 ℃, continuously stirring for 5-6min at the rotating speed of 800-1000r/min, and naturally cooling to room temperature to obtain a premix;

And thirdly, placing the premix in a parallel double-screw extruder, and performing melt extrusion and granulation to obtain the flame-retardant PP plastic particles.

Further, the extrusion parameters in the third step are: 170-180 ℃ in the first area, 180-190 ℃ in the second area, 190-200 ℃ in the third area, 190-210 ℃ in the fourth area, 350-400r/min of screw rotation speed, 20-25Hz of feeding frequency, 3.0-4.0MPa of melt pressure and-0.03-0.06 MPa of vacuum degree.

The invention has the beneficial effects that:

The self-made flame retardant is blended with PP resin, is an organic-inorganic hybrid phosphorus-nitrogen-magnesium flame retardant, has high flame retardancy and good compatibility of organic nitrogen-phosphorus flame retardants, and has the advantages of non-toxicity, smoke suppression and stability of inorganic magnesium flame retardants, so that the defects of the traditional flame retardant are avoided, and the advantages of two flame retardants are also exerted; the flame retardant has good thermal stability and good compatibility with a PP matrix, and can reduce the release of harmful corrosive gas and prolong the flame retardant time on the basis of improving the flame retardant effect and stability; the phosphorus-nitrogen flame retardant component contained in the flame retardant coating can play a role in multiple flame retardant effects on the basis of gas phase and char formation, and plays a role in promoting char formation on the surface of the material, and the carbon layer formed on the surface protects the lower-layer material, delays the decomposition of substances and achieves a good flame retardant effect;

According to the invention, the PP plastic particles with excellent flame retardant effect are prepared through a reasonable formula and a reasonable preparation process, and the PP plastic particles are suitable for preparing parts with high precision requirements and are suitable for popularization and use.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The flame-retardant PP plastic particle is prepared from the following raw materials in parts by weight: 70-80 parts of PP resin, 20-25 parts of flame retardant, 20-22 parts of talcum powder, 3-4 parts of lubricating dispersant, 4-5 parts of heat stabilizer and 3-4 parts of antioxidant;

The lubricating dispersant is one or a compound of ethylene bis-fatty acid amide and stearic acid in any ratio;

The heat stabilizer is an organic tin stabilizer or a calcium-zinc composite stabilizer;

The antioxidant is a compound of phosphite antioxidant 168 and hindered phenol antioxidant 1010 which are mixed according to the mass ratio of 1: 2;

The flame retardant is prepared by the following method:

(1) Adding 3.0kg of hexamethylol melamine, 5.0kg of phosphorous acid and 3.0kg of hydrochloric acid into a reaction kettle provided with a reflux condenser tube, stirring for 70-90min at normal temperature, slowly dropwise adding 7.0kg of hydrochloric acid into the reaction kettle by using a constant-pressure titration funnel, controlling the dropping speed to ensure that the dropwise adding of the hydrochloric acid is finished within 2-3h, then continuously stirring for 110-120min, slowly increasing the temperature in the reaction kettle to 95-98 ℃, carrying out reflux stirring reaction for 8h, cooling, standing the reaction solution, then filtering and distilling to obtain an intermediate;

The mass fraction of the hydrochloric acid is 18 percent; in the step, alcoholic hydroxyl groups on hexamethylol melamine molecules react with P-H on phosphorous acid molecules, so that the phosphorous acid molecules are grafted on the hexamethylol melamine;

(2) Adding 2.2kg of magnesium carbonate and 1.8kg of intermediate prepared in the step (1) into a reaction kettle, stirring to completely dissolve the magnesium carbonate, adding ammonia water to adjust the pH value of a reaction solution to 8.0, heating the system to 98-100 ℃, carrying out reflux reaction for 10-12h, filtering, distilling, standing for 10-12h, filtering again, and placing a filter cake in a vacuum drying oven at 60 ℃ for drying for 7-8h to prepare the flame retardant;

Under the catalytic action of ammonia water, the intermediate molecules react with magnesium carbonate to form a magnesium compound;

The prepared flame retardant is an organic-inorganic hybrid phosphorus-nitrogen-magnesium flame retardant, not only has high flame retardancy and good compatibility of organic nitrogen-phosphorus flame retardants, but also has the advantages of non-toxicity, smoke suppression and stability of inorganic magnesium flame retardants, thereby avoiding the defects of the traditional flame retardant and playing the advantages of two flame retardants; the flame retardant has good thermal stability and good compatibility with a PP matrix, and can reduce the release of harmful corrosive gas and prolong the flame retardant time on the basis of improving the flame retardant effect and stability; the phosphorus-nitrogen flame retardant component contained in the flame retardant coating can play a role in multiple flame retardant effects on the basis of gas phase and char formation, and plays a role in promoting char formation on the surface of the material, and the carbon layer formed on the surface protects the lower-layer material, delays the decomposition of substances and achieves a good flame retardant effect;

The preparation method of the flame-retardant PP plastic particle comprises the following steps:

Firstly, weighing the raw materials according to the parts by weight, putting the raw materials into a high-speed mixer together, stirring and mixing, wherein the mixing temperature is 55-60 ℃, the rotating speed is 800-1000r/min, and the mixing time is 8-10min to obtain a mixture;

Step two, continuously raising the temperature of the mixture obtained in the step one to 100-110 ℃, continuously stirring for 5-6min at the rotating speed of 800-1000r/min, and naturally cooling to room temperature to obtain a premix;

Thirdly, placing the premix in a parallel double-screw extruder, and performing melt extrusion and granulation to obtain the flame-retardant PP plastic particles, wherein the extrusion parameters are as follows: 170-180 ℃ in the first area, 180-190 ℃ in the second area, 190-200 ℃ in the third area, 190-210 ℃ in the fourth area, 350-400r/min of screw rotation speed, 20-25Hz of feeding frequency, 3.0-4.0MPa of melt pressure and-0.03-0.06 MPa of vacuum degree.