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CN-121991436-A - Polypropylene resin composition with flame retardance, preparation method and application thereof

CN121991436ACN 121991436 ACN121991436 ACN 121991436ACN-121991436-A

Abstract

The invention relates to the technical field of polypropylene resin compositions, in particular to a polypropylene resin composition with flame retardance, a preparation method and application thereof. The flame-retardant polypropylene resin composition comprises, by mass, 20-40 parts of polypropylene resin, 45-65 parts of shell powder, 0.5-5.0 parts of compatilizer, 10-25 parts of flame retardant mixture and 0.1-2 parts of auxiliary agent, wherein the flame retardant mixture comprises ammonium polyphosphate, melamine polyphosphate, pentaerythritol and zinc borate ‌. The invention uses polypropylene resin as a polymer matrix, and fills high-content shell powder, so that the composition has flame retardance and good product quality, and can reduce raw material cost. The invention can prevent the structural object from collapsing in the fire disaster and effectively block the flame from spreading by utilizing the ceramic effect of the zinc borate. The present invention can manufacture a board having an attractive surface by using melamine polyphosphate having excellent heat resistance and suppressing gas generated by early decomposition of a flame retardant.

Inventors

  • HUANG XUANGUANG

Assignees

  • 中山铭祺电子科技有限公司

Dates

Publication Date
20260508
Application Date
20260319

Claims (10)

  1. 1. The polypropylene resin composition with flame retardance is characterized by comprising, by mass, 20-40 parts of polypropylene resin, 45-65 parts of shell powder, 0.5-5.0 parts of compatilizer, 10-25 parts of flame retardant mixture and 0.1-2 parts of auxiliary agent, wherein the flame retardant mixture comprises ammonium polyphosphate, melamine polyphosphate, pentaerythritol and zinc borate ‌.
  2. 2. The polypropylene resin composition having flame retardancy as claimed in claim 1, wherein the polypropylene resin is an ethylene-propylene block copolymer having an ethylene content of 3 to 15% and a melt index (MFI, 230 ℃ C./2.16 kg) of 5 to 30g/10min.
  3. 3. The flame retardant polypropylene resin composition according to claim 1, wherein the compatibilizing agent is maleic anhydride-grafted polypropylene having a grafting ratio of 0.5% or more than 0.5%.
  4. 4. The polypropylene resin composition having flame retardancy as claimed in claim 1, wherein the flame retardant mixture comprises, by mass, 5 to 15 parts of ammonium polyphosphate, 1 to 5 parts of melamine polyphosphate, 0.5 to 3 parts of pentaerythritol, 0.5 to 5 parts of zinc borate, and the polymerization degree of ammonium polyphosphate is 1000 or more.
  5. 5. The polypropylene resin composition with flame retardancy as claimed in claim 1, wherein the average particle size of the shell powder is 0.5-5.0 μm, the shell powder is surface-treated with a surface treatment agent, and the coating amount of the surface treatment agent is 0.1-3.0% of the weight of the shell powder.
  6. 6. The polypropylene resin composition having flame retardancy as claimed in claim 5, wherein the surface treatment agent is at least one selected from the group consisting of fatty acid, fatty acid salt and organosilane compound, and the shell powder is subjected to a dry modification surface treatment ‌.
  7. 7. The polypropylene resin composition having flame retardancy as claimed in claim 1, wherein the auxiliary agent comprises one or a combination of an antioxidant, a lubricant, a dispersant and a fluorine-based processing aid.
  8. 8. A method for producing a polypropylene resin composition having flame retardancy as defined in any one of claims 1 to 7, comprising the steps of, S1, drying raw materials; S2, in a double-screw extruder, adding the polypropylene resin, the shell powder, the compatilizer and part or all of the auxiliary agents into a main hopper, and adding the flame retardant mixture and the rest of the auxiliary agents through a side feeder; s3, in the process of the step S2, vacuum below-0.05 MPa is applied to an exhaust area of the double-screw extruder so as to remove moisture and volatile gas; and S4, extruding the final mixture through a die head, cooling, and cutting into a granule shape to obtain a finished product.
  9. 9. The method for producing a polypropylene resin composition having flame retardancy as claimed in claim 8, wherein the side feeding port of the side feeder is located at 40% -60% of the total length of the twin-screw extruder.
  10. 10. Use of a polypropylene resin composition having flame retardancy according to any one of claims 1 to 7, characterized in that the polypropylene resin composition is used as a building decoration material, an automotive interior material, a sheet material, a housing for electric parts, the sheet material being in the form of a sheet of a structure of a danplat sheet comprising a hollow layer or a solid structure.

Description

Polypropylene resin composition with flame retardance, preparation method and application thereof Technical Field The invention relates to the technical field of polypropylene resin compositions, in particular to a polypropylene resin composition with flame retardance, a preparation method and application thereof. Background Polypropylene resins are widely used in various industrial fields such as interior and exterior materials for buildings, sheet materials for logistics, interior materials for automobiles, etc., because of their excellent chemical resistance, moldability, low specific gravity, etc. However, polypropylene has a limiting oxygen index as low as about 17-18, is a very flammable material, and releases a large amount of heat during combustion, with the concomitant generation of flame-carrying molten drips, which can lead to rapid spread of fire, a significant drawback in its use. In order to solve the above-mentioned flammability problem, a method of adding a halogen flame retardant has been mainly used in the past. However, halogen-based flame retardants generate toxic gases including dioxin upon combustion, causing serious environmental safety problems. Therefore, in recent years, flame retardant technologies using halogen-free flame retardants such as phosphorus-based flame retardants and nitrogen-based flame retardants have been a focus of research. On the other hand, in order to ensure price competitiveness of the product, there is an attempt to highly fill the resin with an inorganic filler such as shell powder (calcium carbonate as a main component) and talc. However, when the content of the inorganic filler exceeds 45% by weight (45% by weight is contained), that is, in a high-filled system, the following significant drawbacks are encountered: First, flame retardant efficiency is significantly reduced. Due to the reduced relative content of matrix resin, the char layer formed by the flame retardant upon combustion is not strong enough to support the weight of the inorganic filler, resulting in collapse of the char layer and loss of barrier function. Second, processability is deteriorated. The addition of high inorganic filler increases the melt viscosity of the resin in an exponential manner, which leads to excessively high die pressure during extrusion molding, and easily causes melt fracture or shark skin phenomenon, thereby roughening the surface of the product. Furthermore, physical properties are degraded. The compatibility between the inorganic filler and the polymer resin matrix is poor, and the interfacial binding force is weak, so that the mechanical properties such as impact strength and the like of the final product are greatly reduced. Therefore, there is an urgent need to develop a novel polypropylene resin composition which can contain a high content of an inorganic filler and impart excellent flame retardancy to a material to achieve the UL 94V-0 level while ensuring a smooth surface quality of a molded article, and a molding process thereof. Disclosure of Invention In order to solve the above-mentioned problems of flammability of polypropylene resin, the prior art adopts a method of adding halogen flame retardant, but has the following problems that toxic gas is generated during combustion, environmental safety is caused, when the content of inorganic filler exceeds 45 wt%, the technical problems of flame retardant efficiency decline, processability deterioration and physical property decline occur in a high-filling system, the invention provides a method of using polypropylene resin as a polymer matrix, and the composition has flame retardance and good product quality while filling high content of shell powder, which specifically adopts the following technical scheme: The polypropylene resin composition with flame retardance comprises, by mass, 20-40 parts of polypropylene resin, 45-65 parts of shell powder, 0.5-5.0 parts of compatilizer, 10-25 parts of flame retardant mixture and 0.1-2 parts of auxiliary agent, wherein the flame retardant mixture comprises ammonium polyphosphate, melamine polyphosphate, pentaerythritol and zinc borate ‌. According to the invention, the flame retardant mixture containing ammonium polyphosphate, melamine polyphosphate, pentaerythritol and zinc borate is compounded in the polypropylene matrix, and the material has a good flame retardant effect under a high-content shell powder filling system of 45-65 parts by weight. In the combustion process, the synergistic effect of ammonium polyphosphate and pentaerythritol promotes the surface of the matrix to form an expanded carbon layer, and melamine polyphosphate is used as an air source to promote the foaming of the carbon layer, so that the heat insulation effect is improved. The zinc borate is melted at high temperature, so that a loose carbon layer structure due to the existence of a large amount of shell powder can be bonded, the compactness and strength of the carbon layer are enhanced, th