CN112143115B - Preparation method of flame-retardant polypropylene material - Google Patents
Preparation method of flame-retardant polypropylene material Download PDFInfo
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- CN112143115B CN112143115B CN202010990201.6A CN202010990201A CN112143115B CN 112143115 B CN112143115 B CN 112143115B CN 202010990201 A CN202010990201 A CN 202010990201A CN 112143115 B CN112143115 B CN 112143115B
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
- C08L23/02—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
- C08L23/10—Homopolymers or copolymers of propene
- C08L23/14—Copolymers of propene
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2423/00—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers
- C08J2423/02—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers not modified by chemical after treatment
- C08J2423/10—Homopolymers or copolymers of propene
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J3/00—Processes of treating or compounding macromolecular substances
- C08J3/20—Compounding polymers with additives, e.g. colouring
- C08J3/22—Compounding polymers with additives, e.g. colouring using masterbatch techniques
- C08J3/226—Compounding polymers with additives, e.g. colouring using masterbatch techniques using a polymer as a carrier
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
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- C08K2201/011—Nanostructured additives
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/04—Oxygen-containing compounds
- C08K5/14—Peroxides
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- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2201/00—Properties
- C08L2201/02—Flame or fire retardant/resistant
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Abstract
The invention discloses a preparation method of a flame-retardant polypropylene material, which comprises the following raw materials in parts by weight: 80-86 parts of polypropylene, 14-20 parts of flame retardant, 0.1-0.8 part of peroxide master batch, 0.1-0.5 part of antioxidant, 0.1-0.5 part of lubricant, 0.1-0.5 part of light stabilizer and 1-2 parts of carbon black, and the preparation method comprises the following steps: s1, adding polypropylene, peroxide master batches, an antioxidant and a lubricant into a high-pressure mixing pot, fully mixing, melting, plasticizing, blending by a double-screw extruder, and extruding and granulating to obtain polymer particles; and S2, adding the polymer particles, the flame retardant, the antioxidant, the lubricant, the light stabilizer and the carbon black into a high-mixing pot for premixing, melting by a double-screw extruder, blending, extruding, granulating and drying to obtain the flame-retardant polypropylene material. The flame-retardant polypropylene material is prepared by a two-step method, so that the flame-retardant property of the polypropylene material is effectively improved, and the material has low content of residual peroxide and high weather resistance.
Description
Technical Field
The invention relates to the field of high polymer materials, in particular to a preparation method of a flame-retardant polypropylene material.
Background
Polypropylene materials are one of five general-purpose resin materials, and are widely applied to the fields of packaging, electronics and the like because of the characteristics of light weight, easy processing and the like. However, since the polypropylene material has an oxygen index of about 17 to 18%, and is a flammable material, it has a limitation in use in many applications. The polypropylene material can be divided into homopolymerization type and copolymerization type, wherein the homopolymerization type polypropylene has poor toughness, particularly, a punched part is easy to crack when low-temperature impact is carried out, but the polypropylene material has good fluidity and high tensile strength, and is easy to carry out flame retardant modification on the polypropylene material. The copolymer polypropylene has improved low-temperature impact properties and better flexibility, but the fluidity of the copolymer polypropylene is slightly inferior to that of the homopolymer polypropylene.
At present, peroxide cooling master batches are added in the preparation of flame-retardant polypropylene materials, so that the flowability of a formula system is effectively improved, the flame-retardant effect of the system is improved, and the flame retardance of the materials is improved.
Disclosure of Invention
In order to solve the defects in the background art, the invention aims to provide a preparation method of a flame-retardant polypropylene material, which is characterized in that the flame-retardant polypropylene material is prepared by a two-step method, polypropylene and peroxide master batches are melted and blended, and then granulated to obtain pretreated polymer particles, and then the pretreated polymer particles are blended and granulated with a flame retardant, an antioxidant, a lubricant, a light stabilizer and carbon black, so that the flame retardant property of the polypropylene material is effectively improved, and meanwhile, the material has low content of residual peroxide and stronger weather resistance.
The purpose of the invention can be realized by the following technical scheme:
a preparation method of a flame-retardant polypropylene material comprises the following raw materials in parts by weight: 80-86 parts of polypropylene, 14-20 parts of flame retardant, 0.1-0.8 part of peroxide master batch, 0.1-0.5 part of antioxidant, 0.1-0.5 part of lubricant, 0.1-0.5 part of light stabilizer and 1-2 parts of carbon black, and the preparation method comprises the following steps:
s1, adding polypropylene, peroxide master batches, an antioxidant and a lubricant into a high mixing pot, fully mixing to obtain a mixture A, and then carrying out melting, plasticizing and blending on the mixture A through a double-screw extruder, and then carrying out extrusion granulation to obtain polymer particles B;
s2, adding the polymer particles B, a flame retardant, an antioxidant, a lubricant, a light stabilizer and carbon black into a high mixing pot for premixing to obtain a mixture C, then melting and blending the mixture C through a double-screw extruder, extruding and granulating, and drying to obtain the flame-retardant polypropylene material.
Preferably, the flame retardant is a composite of an octabromine flame retardant and antimony trioxide, and the octabromine flame retardant is at least one of octabromo ether or octabromo bisphenol S ether.
Preferably, the peroxide master batch takes polypropylene as a carrier, and the main component of the peroxide master batch is at least one of di-tert-butyl peroxide (DTBP), 2, 5-dimethyl-1-2, 5-bis (tert-butylperoxy) -hexane (DHBP) and dicumyl peroxide (DCP).
Preferably, the carbon black is a channel black, and the carbon black has a particle size of 15 to 25nm.
Preferably, the light stabilizer is one or more of benzophenones, benzotriazoles, triazines, substituted acrylonitriles and Hindered Amines (HAL).
Preferably, the lubricant is a mixture of calcium stearate and an EBS lubricant according to the mass ratio of 1-3.
Preferably, the antioxidants include primary antioxidant 1010 and secondary antioxidant 168.
Preferably, the length ratio L: D of the twin-screw extruder in the step S1 and the step S2 is 30-40, the rotating speed of the screw is 260-450r/min, and the feeding speed is 8-20rpm.
Preferably, the temperature of each zone of the twin-screw extruder is set as follows: 170-200 ℃ in the first zone, 180-200 ℃ in the second zone, 180-200 ℃ in the third zone, 160-190 ℃ in the fourth zone, 160-190 ℃ in the fifth zone, 160-190 ℃ in the sixth zone, 160-190 ℃ in the seventh zone, 160-190 ℃ in the eighth zone, 170-190 ℃ in the ninth zone and 180-200 ℃ in the tenth zone.
The invention has the beneficial effects that:
the flame-retardant polypropylene material comprises components such as polypropylene, a flame retardant, peroxide master batches, an antioxidant, a lubricant, a light stabilizer, carbon black and the like, the flowability of a formula system is effectively improved through the peroxide master batches, the flame-retardant property of the composite material is effectively improved by combining the flame retardant, the weather resistance of the composite material is improved through the antioxidant and the light stabilizer, and a carbon black filler is added and uniformly dispersed in a polymer material to form a three-dimensional elastic network so as to enhance the stability of the polymer material;
the flame-retardant polypropylene material is prepared by a two-step method, the polypropylene and peroxide master batches are melted and blended, and then granulated to obtain the pretreated polymer particles, and the pretreated polymer particles are blended and granulated with the flame retardant, the antioxidant, the lubricant, the light stabilizer and the carbon black, so that the flame retardant property of the polypropylene material is effectively improved, and meanwhile, the material is low in residual peroxide content and has strong weather resistance.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious 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.
In the description of the present invention, it is to be understood that the terms "opening," "upper," "lower," "thickness," "top," "middle," "length," "inner," "peripheral," and the like are used in an orientation or positional relationship merely to facilitate description of the invention and to simplify the description, and are not intended to indicate or imply that the referenced components or elements must be in a particular orientation, constructed and operative in a particular orientation, and are not to be construed as limiting the invention.
The raw materials used in the examples and comparative examples of the present invention are illustrated below, by way of example only and not by way of limitation:
copolymerized polypropylene resin: wuhan petrochemical K8003
Octabromo flame retardant: weifang modest quantity chemical company eight bromo ether
Antimony powder: antimony trioxide from Huaxingyiny Ltd
Peroxide master batch: is commercially available
Lubricant: calcium stearate, EBS lubricants are generally commercially available
Antioxidant: antioxidant 1010 antioxidant 168
Light stabilizer: benzotriazole UV326 and hindered amine light stabilizer UV3529
Carbon black: channel black, commercially available
Example 1
A preparation method of a flame-retardant polypropylene material comprises the following steps:
s1, fully mixing K800386 parts, 0.1 part of peroxide master batch, 0.3 part of antioxidant and 0.3 part of lubricant in a high mixing pot, melting, plasticizing and blending the obtained mixture A through a double-screw extruder, and then extruding and granulating to obtain polymer particles B, wherein the used double-screw extruder L is D =35, the rotating speed of a screw is 400r/min, the feeding speed is 12rpm, and the temperature of each area of the extruder is set as follows: a first zone of 200 ℃, a second zone of 180 ℃, a third zone of 180 ℃, a fourth zone of 185 ℃, a fifth zone of 180 ℃, a sixth zone of 185 ℃, a seventh zone of 180 ℃, an eighth zone of 180 ℃, a ninth zone of 180 ℃, and a tenth zone of 160 ℃;
s2, premixing the polymer particles B obtained after pretreatment with 14 parts of flame retardant, 0.2 part of antioxidant, 0.3 part of lubricant, 0.3 part of light stabilizer and 0.6 part of carbon black in a high mixing pot for 10min to obtain a mixture C, then performing extrusion granulation and drying to obtain the flame-retardant polypropylene material, wherein a double-screw extruder L is characterized in that D =40: first zone 170 ℃, second zone 180 ℃, third zone 185 ℃, fourth zone 160 ℃, fifth zone 170 ℃, sixth zone 180 ℃, seventh zone 180 ℃, eighth zone 180 ℃, ninth zone 180 ℃, tenth zone 185 ℃.
Example 2
The concrete operation was carried out as in example 1, except that the amount of the flame retardant added in the mass fraction in step S2 was 20 parts.
Example 3:
the specific operation was carried out as in example 1, except that the mass fraction of the peroxide master batch added in step S1 was 0.4 parts.
Example 4:
the concrete operation was carried out as in example 3, except that the amount of the flame retardant added in the mass fraction in step S2 was 20 parts.
Example 5:
the operation was carried out as in example 1 except that the mass fraction of the peroxide master batch added in step S1 was 0.8 part.
Example 6:
the concrete operation was carried out as in example 5, except that the amount of the flame retardant added in the mass fraction in step S2 was 20 parts.
Comparative example 1:
the specific procedure was as in example 1, except that no peroxide masterbatch was added in step S1.
Comparative example 2:
a preparation method of a flame-retardant polypropylene material comprises the following steps:
carrying out one-pot premixing on K800386 parts, 0.1 part of peroxide master batch, 14 parts of flame retardant, 0.2 part of antioxidant, 0.3 part of lubricant, 0.3 part of light stabilizer and 0.6 part of carbon black in a high mixing pot for 10min to obtain a mixture, then carrying out extrusion granulation and drying to obtain the flame-retardant polypropylene material, wherein a double-screw extruder L: D =40: first zone 170 ℃, second zone 180 ℃, third zone 185 ℃, fourth zone 160 ℃, fifth zone 170 ℃, sixth zone 180 ℃, seventh zone 180 ℃, eighth zone 180 ℃, ninth zone 180 ℃, tenth zone 185 ℃.
Comparative example 3:
the detailed operation was carried out in accordance with comparative example 2, except that the amount of the peroxide master batch was 0.8 part.
Comparative example 4:
the specific procedure was as in example 1, except that no light stabilizer was added in step S2.
Performance testing
The composites obtained in examples 1 to 6 and comparative examples 1 to 4 were subjected to the corresponding performance tests according to the following criteria: the melt index GB/T3682, tensile test GB/T1040.2, bending test GB/T9341, impact test GB/T1843.1, the flame standard being in accordance with the GBUL94 standard, the data obtained after ageing the UVB for 96 hours are shown in Table 1 below:
as can be seen from Table 1, the flame-retardant polypropylene material disclosed by the invention is excellent in flame retardant property and good in self-extinguishing property, so that the prepared flame-retardant polypropylene material V0 has the effects of flame retardance, lubrication, energy consumption saving and the like.
In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed.
Claims (7)
1. The preparation method of the flame-retardant polypropylene material is characterized by comprising the following raw materials in parts by weight: 80-86 parts of polypropylene, 14-20 parts of flame retardant, 0.1-0.8 part of peroxide master batch, 0.1-0.5 part of antioxidant, 0.1-0.5 part of lubricant, 0.1-0.5 part of light stabilizer and 1-2 parts of carbon black, and the preparation method comprises the following steps:
s1, adding polypropylene, peroxide master batches, an antioxidant and a lubricant into a high-speed mixing pot, fully mixing to obtain a mixture A, then melting, plasticizing and blending the mixture A through a double-screw extruder, and extruding and granulating to obtain polymer particles B;
s2, adding the polymer particles B, a flame retardant, an antioxidant, a lubricant, a light stabilizer and carbon black into a high mixing kettle for premixing to obtain a mixture C, then melting and blending the mixture C through a double-screw extruder, extruding and granulating, and drying to obtain a flame-retardant polypropylene material;
the polypropylene is copolymerized polypropylene;
the flame retardant is a compound of an octabromine flame retardant and antimony trioxide, and the octabromine flame retardant is at least one of octabromo ether or octabromo bisphenol S ether;
the peroxide master batch takes polypropylene as a carrier, and the main component of the peroxide master batch is at least one of di-tert-butyl peroxide (DTBP), 2, 5-dimethyl 1-2, 5-bis (tert-butylperoxy) -hexane (DHBP) and dicumyl peroxide (DCP).
2. The method for preparing flame retardant polypropylene material according to claim 1, wherein the carbon black is channel black, and the particle size of the carbon black is 15-25nm.
3. The method for preparing a flame retardant polypropylene material according to claim 1, wherein the light stabilizer is one or more of benzophenones, benzotriazoles, triazines, substituted acrylonitriles and Hindered Amines (HAL).
4. The preparation method of the flame-retardant polypropylene material according to claim 1, wherein the lubricant is a mixture of calcium stearate and an EBS lubricant according to a mass ratio of 1.
5. The method for preparing flame retardant polypropylene material according to claim 1, wherein the antioxidant comprises primary antioxidant 1010 and secondary antioxidant 168.
6. The method for preparing a flame retardant polypropylene material according to claim 1, wherein the length-to-diameter ratio L: D of the twin-screw extruder in the steps S1 and S2 is 30-40, the rotation speed of the screw is 260-450r/min, and the feeding speed is 8-20rpm.
7. The method for preparing the flame retardant polypropylene material according to claim 6, wherein the temperature of each zone of the twin-screw extruder is set as follows: 170-200 ℃ in the first zone, 180-200 ℃ in the second zone, 180-200 ℃ in the third zone, 160-190 ℃ in the fourth zone, 160-190 ℃ in the fifth zone, 160-190 ℃ in the sixth zone, 160-190 ℃ in the seventh zone, 160-190 ℃ in the eighth zone, 170-190 ℃ in the ninth zone, and 180-200 ℃ in the tenth zone.
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| CN103951876A (en) * | 2014-04-02 | 2014-07-30 | 合肥杰事杰新材料股份有限公司 | Environment-friendly type high-toughness and flame retardation polypropylene material as well as preparation method thereof |
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