阅读说明：本技术 改性阻燃abs材料及其制备方法 (Modified flame-retardant ABS material and preparation method thereof ) 是由 黄浩 杨华军 蔡雄 于 2019-09-26 设计创作，主要内容包括：本发明涉及一种膨胀蛭石粉改性阻燃ABS材料及其制备方法。所述膨胀蛭石粉改性阻燃ABS材料由以下原料制备而成：ABS树脂、溴代三嗪、三氧化二锑、相容剂、有机化膨胀蛭石粉、润滑剂、主抗氧剂、辅抗氧剂和抗滴落剂。该膨胀蛭石粉改性阻燃ABS材料具有良好阻燃性能、耐热性、较高的材料光泽度以及流动性,可广泛应用于电子电器元件、仪器壳体等塑料制品中。(The invention relates to an expanded vermiculite powder modified flame-retardant ABS material and a preparation method thereof. The expanded vermiculite powder modified flame-retardant ABS material is prepared from the following raw materials: ABS resin, bromotriazine, antimony trioxide, a compatilizer, organic expanded vermiculite powder, a lubricant, a main antioxidant, an auxiliary antioxidant and an anti-dripping agent. The expanded vermiculite powder modified flame-retardant ABS material has good flame-retardant property, heat resistance, higher material glossiness and fluidity, and can be widely applied to plastic products such as electronic and electrical components, instrument shells and the like.)

1. The modified flame-retardant ABS material is characterized by being prepared from the following raw materials in parts by weight:

2. the modified flame-retardant ABS material according to claim 1 is prepared from the following raw materials in parts by weight:

3. the modified flame retardant ABS material of claim 1 or 2 wherein the compatibilizer is one or a combination of maleic anhydride grafted ABS, maleic anhydride and styrene copolymer SMA.

4. The modified flame-retardant ABS material according to any of claims 1 or 2, characterized in that the organized expanded vermiculite powder is organically treated with hyperbranched dispersant of hyperbranched polyester or hyperbranched dispersant of dendritic polyamidoamine; the hyperbranched dispersant is one or a combination of two of a hyperbranched dispersant containing terminal hydroxyl or a hyperbranched dispersant containing terminal amino.

5. The modified flame-retardant ABS material according to claim 4, wherein the hyperbranched dispersant containing terminal hydroxyl groups is selected from hyperbranched polyesters or hyperbranched dispersants of dendritic polyamidoamines;

the hyperbranched dispersant containing terminal amino groups is selected from hyperbranched dispersants of dendritic polyamidoamines.

6. The modified flame retardant ABS material of any one of claims 1 or 2 wherein the anti-dripping agent is modified polytetrafluoroethylene; the lubricant is ethylene bis stearamide; the antioxidant is a compound of beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid octadecyl ester and tri (2, 4-di-tert-butyl) phenyl phosphite.

7. The preparation method of the modified flame-retardant ABS material as claimed in any of claims 1 to 6, characterized by comprising the following steps:

(1) taking expanded vermiculite powder, adding a hyperbranched dispersant, and stirring and mixing on a high-speed stirrer under the condition of heating to obtain organic expanded vermiculite powder;

(2) mixing ABS resin, bromotriazine, antimony trioxide, a compatilizer, organic expanded vermiculite powder, a lubricant, an antioxidant and an anti-dripping agent on a high-speed mixer according to the weight parts of the raw materials of any one of claims 1 to 6;

(3) and (3) putting the uniformly mixed raw materials in the step (2) into a parallel double-screw extruder, and granulating after melt extrusion.

8. The method according to claim 6, wherein the process parameters of step (3) are as follows: the temperature of the first zone is 180-200 ℃, the temperature of the second zone is 185-205 ℃, the temperature of the third zone is 190-210 ℃, the temperature of the fourth zone is 185-205 ℃, the temperature of the fifth zone is 185-205 ℃, the temperature of the sixth zone is 185-205 ℃, the temperature of the seventh zone is 180-200 ℃, the temperature of the eighth zone is 180-200 ℃, the temperature of a machine head is 200-220 ℃, the rotating speed of a double-screw extruder is set to be 300-600 rpm, and the vacuum degree is set to be-0.04-0.06 MPa.

9. The preparation method according to claim 8, wherein the process parameters of the step (3) are as follows: the temperature of the first zone is 180-190 ℃, the temperature of the second zone is 185-195 ℃, the temperature of the third zone is 190-200 ℃, the temperature of the fourth zone is 185-195 ℃, the temperature of the fifth zone is 185-195 ℃, the temperature of the sixth zone is 185-195 ℃, the temperature of the seventh zone is 180-190 ℃, the temperature of the eighth zone is 180-190 ℃, the temperature of the machine head is 200-210 ℃, the rotating speed of the double-screw extruder is set to be 400-500 rpm, and the vacuum degree is set to be-0.04-0.06 MPa.

10. The production method according to any one of claims 7 to 9, wherein the screw shape of the parallel twin-screw extruder is a twin-screw flight, and the ratio L/D of the length L of the screw to the diameter D of the screw is 35 to 45.

Technical Field

The invention relates to the field of high polymer materials, and in particular relates to an expanded vermiculite powder modified flame-retardant ABS material and a preparation method thereof.

Background

Acrylonitrile-butadiene-styrene (ABS) has good chemical resistance and processability, high gloss and low cost. Due to the improvement of living standard of people, the fire-proof requirement of used plastic materials is higher and higher, for example, flame-retardant ABS materials used for household appliances, automobile parts and the like have the development trend that the V-0 grade is improved to the 5VA grade.

The vermiculite is a lamellar structure magnesium-containing aluminosilicate mineral, the volume of the vermiculite is increased by 6-15 times after being burnt at high temperature, and the density of the expanded vermiculite is 100-130 kg/m³The material has a fine air spacing layer, thereby being an excellent heat preservation, heat insulation and sound absorption material; the thermal conductivity is small, and the density is 50-200 kg/m³It is a good heat-insulating material. The expanded vermiculite powder with good quality has the maximum use temperature of 1100 ℃, has good electrical insulation, light volume weight, freezing resistance, heat preservation, heat insulation, sound absorption and other properties, but the application of the expanded vermiculite powder in the aspect of flame retardant synergy needs to be further researched.

In general, due to the addition of antimony bromide flame retardant, impact performance and glossiness of ABS materials are obviously reduced, so that the improvement of flame retardant effect is realized by optimizing flame retardant efficiency instead of improving the addition amount of the flame retardant. In the existing mode, functional filler is added into a flame-retardant ABS material, so that the flame-retardant effect of the flame-retardant ABS is improved.

In recent years, heat resistance of flame-retardant ABS has been improved at home and abroad, and a heat-resistant agent or Polycarbonate (PC) has been generally added. The addition of heat-resistant agents decreases the impact and flow properties of ABS materials, while the addition of PC resins increases impact, but both add cost. Currently, some studies on flame retardant ABS materials are made in the prior art, such as: chinese patent CN 106832736A discloses a high heat-resistant flame-retardant ABS material, which is composed of 60-80% by mass of ABS resin, 8-20% by mass of brominated flame retardant, 3-10% by mass of antimony flame retardant, 1-2% by mass of composite smoke suppressor, 1-5% by mass of inorganic flame-retardant synergist, 0.1-1% by mass of anti-dripping agent and 1-5% by mass of other processing aids; the inorganic flame-retardant synergist is any one or the combination of more than two of talcum powder, zinc borate, wollastonite and mica, and the flame-retardant synergistic effect of expanded vermiculite powder is not mentioned. Chinese patent CN 104072805A discloses a preparation method of a vermiculite-based composite flame retardant, which comprises the following components by mass: 20-35 parts of modified vermiculite, 30-45 parts of magnesium hydroxide, 15-25 parts of phosphorus flame retardant and 2-5 parts of silane coupling agent; the raw ore vermiculite with high interlayer water content and structural water content is adopted for acidizing, the vermiculite subjected to high-temperature expansion treatment is not utilized, the addition content of the flame retardant is high, and the material gloss is poor. Chinese patent CN 101503553A discloses a halogen-free flame-retardant high impact polystyrene composite material prepared by taking vermiculite as a flame retardant additive, the composite material is prepared by mixing vermiculite powder crushed to 100-500 meshes and a halogen-free flame retardant in a mass ratio of 1: 1-1: 10 to form a vermiculite composite flame retardant, banburying the vermiculite composite flame retardant and the high impact polystyrene in a mass ratio of 1: 1-1: 5, and performing injection molding; the natural vermiculite is ground and then added for use, the natural vermiculite is not directly added after high-temperature expansion treatment, the interlayer water content is high, and the phenomenon of serious material waste is easy to occur in an injection molding part. Chinese patent CN108250664A discloses a flame-retardant environment-friendly automotive interior panel and a preparation method thereof, wherein the flame-retardant environment-friendly automotive interior panel comprises the following raw materials: 20-60 parts of ABS resin, 40-80 parts of polycarbonate resin, 1-5 parts of lubricant, 5-10 parts of tourmaline powder, 5-10 parts of vermiculite powder, 2002-8 parts of polyethylene glycol, 50-70 parts of aniline, 50-70 parts of 10 wt% ammonium persulfate solution, 1-2 parts of concentrated sulfuric acid and 90-150 parts of distilled water; wherein the addition of the vermiculite powder mainly plays a role in bacteriostasis effect and negative ion release.

Chinese patent CN 104744874A discloses a high heat-resistant low-smoke flame-retardant ABS material and a preparation method thereof, which comprises 58-80% by mass of ABS resin, 8-20% by mass of brominated flame retardant, 3-10% by mass of antimony flame retardant, 1-2% by mass of composite smoke suppressor and 1-5% by mass of other processing aids; the vermiculite powder used is not mentioned to be subjected to a high-temperature expansion treatment. Chinese patent CN 107629382A discloses an ABS composite material for a fan remote controller shell, which comprises the following raw materials in parts by weight: 95-105 parts of main material, 1-2 parts of butyl phthalate, 1-2 parts of methyl silicone oil, 10-18 parts of carbon fiber, 5-14 parts of vermiculite powder, 2-8 parts of coconut shell carbon powder, 40-50 parts of precipitated barium sulfate, 2-4 parts of crosslinking agent, 1-2 parts of anti-aging agent MBZ and 1-2 parts of anti-aging agent BLE. The main materials comprise the following components in parts by weight: 45-66 parts of a methyl methacrylate-butadiene-styrene terpolymer, 20-30 parts of ABS resin and 14-20 parts of modified polyurethane; the vermiculite powders used are also not mentioned as having been subjected to a high-temperature expansion treatment.

Disclosure of Invention

Accordingly, there is a need for an ABS material that has good flame retardant properties, gloss, heat resistance and flowability, and can be applied to plastic products such as electronic and electrical components and instrument housings.

In order to achieve the purpose, the invention provides the following technical scheme:

the modified flame-retardant ABS material is prepared from the following raw materials in parts by weight:

in some of the examples, the composition is prepared from the following raw materials in parts by weight:

in some embodiments, the compatibilizer is one or a combination of maleic anhydride grafted ABS, maleic anhydride, and styrene copolymer SMA.

In some embodiments, the organic expanded vermiculite powder is organically treated with hyperbranched dispersant of hyperbranched polyester or hyperbranched dispersant of dendritic polyamidoamine.

The organic expanded vermiculite powder is organically treated by hyperbranched dispersant of hyperbranched polyester or hyperbranched dispersant of dendritic polyamidoamine; the hyperbranched dispersant is one or a combination of two of a hyperbranched dispersant containing terminal hydroxyl or a hyperbranched dispersant containing terminal amino.

In some of these embodiments, the anti-drip agent is a methyl methacrylate-styrene copolymer coated polytetrafluoroethylene; the lubricant is Ethylene Bis Stearamide (EBS); the antioxidant is a compound of beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid octadecyl ester (a main antioxidant) and tri (2, 4-di-tert-butyl) phenyl phosphite (an auxiliary antioxidant).

The invention also aims to provide a preparation method of the modified flame-retardant ABS material, which comprises the following specific technical scheme:

the preparation method of the modified flame-retardant ABS material is characterized by comprising the following steps:

(1) taking expanded vermiculite powder, adding a hyperbranched dispersant, and stirring and mixing on a high-speed stirrer under the condition of heating to obtain organic expanded vermiculite powder;

(2) mixing ABS resin, bromotriazine, antimony trioxide, a compatilizer, organic expanded vermiculite powder, a lubricant, an antioxidant and an anti-dripping agent on a high-speed stirrer according to the weight parts of the raw materials;

(3) and (3) putting the uniformly mixed raw materials in the step (2) into a parallel double-screw extruder, and granulating after melt extrusion.

In some of these embodiments, the process parameters of step (3) are as follows: the temperature of the first zone is 180-200 ℃, the temperature of the second zone is 185-205 ℃, the temperature of the third zone is 190-210 ℃, the temperature of the fourth zone is 185-205 ℃, the temperature of the fifth zone is 185-205 ℃, the temperature of the sixth zone is 185-205 ℃, the temperature of the seventh zone is 180-200 ℃, the temperature of the eighth zone is 180-200 ℃, the temperature of a machine head is 200-220 ℃, the rotating speed of a double-screw extruder is set to be 300-600 rpm, and the vacuum degree is set to be-0.04-0.06 MPa.

In some of the embodiments, the process parameters of step (3) are: the temperature of the first zone is 180-190 ℃, the temperature of the second zone is 185-195 ℃, the temperature of the third zone is 190-200 ℃, the temperature of the fourth zone is 185-195 ℃, the temperature of the fifth zone is 185-195 ℃, the temperature of the sixth zone is 185-195 ℃, the temperature of the seventh zone is 180-190 ℃, the temperature of the eighth zone is 180-190 ℃, the temperature of the machine head is 200-210 ℃, the rotating speed of the double-screw extruder is set to be 400-500 rpm, and the vacuum degree is set to be-0.04-0.06 MPa.

In some of these embodiments, the screw shape of the parallel twin screw extruder is a twin screw flight; the ratio L/D of the length L of the screw to the diameter D of the screw is 35 to 45.

The expanded vermiculite modified flame-retardant ABS material has the following principle:

the flame retardant mechanism of the common bromine-antimony compound flame retardant ABS mainly comprises the following aspects: antimony trioxide is heated and melted at the initial stage of combustion, a layer of protective film is coated on the surface of the material to isolate oxygen, and meanwhile, the melting generates endothermic reaction to reduce the combustion temperature of the material; at high temperature, the antimony trioxide is gasified to dilute the air at the burning position, thereby achieving the flame-retardant effect. The synergistic mechanism of the antimony trioxide and the bromotriazine during compounding use is that the bromotriazine is firstly decomposed to generate HBr and simultaneously generate SbOBr, and the SbOBr is decomposed by heating to absorb a large amount of heat and simultaneously generate SbBr₃。SbBr₃Br is generated at the burning position, and Br is combined with free radical H or HO with strong activity in the flame to terminate the chain reaction at the burning position, thereby achieving the function of flame retardance. Simultaneous SbOBr and SbBr₃The steam has high density, is attached to the surface of a combustion position, plays a role in isolating and diluting the air concentration and the concentration of gasified combustible substances, and is condensed into solid or liquid particles above the flame, so that the combustion speed is slowed down or gradually stopped.

The anti-dripping agent is fiberized under the shearing action of the extrusion screw to form a net structure in the material, the material is heated and shrunk during combustion to prevent the material from melting and dripping, and the flame retardance of the material can be improved; the talcum powder is a hydrous silicate mineral with an irregular lamellar structure, and can form a porous covering on the surface of the material when the material is combusted, so that the heat insulation effect is achieved, small molecular substances generated by plastic decomposition are prevented from diffusing to the surface, external oxygen is prevented from migrating inwards, the combustion reaction is slowed down, the influence of the irregular lamellar structure talcum powder on the gloss of ABS is large, the gloss is obviously reduced due to a small amount of the irregular lamellar structure talcum powder, and meanwhile, the rigidity of the material can be improved due to the lamellar structure; precipitated barium sulfate is of a nearly spherical structure, has a weak reinforcing effect, but has a small influence on the gloss of the material.

The main chain part of ABS or polystyrene chain segment in the compatilizer has good compatibility with ABS, and maleic anhydride with high active group in the compatilizer can react with hydroxyl or amino in the hyperbranched dispersant to form covalent bond, so that the interface strength of ABS resin and expanded vermiculite powder is improved, and the thickness and the adhesive force of a phase interface are improved, thereby improving the mechanical property and the gloss of the material, but excessive addition of the compatilizer can cause the viscosity of the material to be increased and the melt index to be reduced.

The unexpanded vermiculite powder contains interlayer hydrates and can cause poor surface decoration when directly added into the flame-retardant ABS. The amount of interlayer water depends on the hydration capacity of interlayer cations and the ambient temperature and humidity. Mg in vermiculite powder²⁺，Fe³⁺With Al³⁺The theoretical values of the enthalpy of hydration of (a) are 2044.28kJ/mol, 4494.7kJ/mol, 4955.79kJ/mol, respectively. The greater the enthalpy of hydration, the more heat is given off during the hydration of the metal ions and the hydrated cation M (H) is formed₂O)_n ^Z+The more stable, the less easily dehydrated after absorbing moisture. The vermiculite powder subjected to high-temperature burning expansion treatment has a fine air spacing layer, although interlayer water is reduced, a small amount of water is still absorbed and moistened to form a cluster particle, and the vermiculite powder is easy to disperse badly by direct addition, so that a good flame retardant effect and a good appearance effect cannot be achieved. In order to solve the problem, the invention organically treats the expanded vermiculite powder by adding the hyperbranched dispersant, adds the mutual cooperation of the compatilizer, the antimony bromide flame retardant and the ABS resin, and extrudes and granulates, so that the flame retardant effect and the appearance of the obtained product are stable. Since the hyperbranched dispersant contains hydroxyl or amino functional groups, the hyperbranched dispersant can be mixed with Mg of expanded vermiculite powder²⁺，Fe³⁺With Al³⁺Forming a complex structure, reacting maleic anhydride group with hydroxyl or amino in the compatilizer to form a stable covalent bond, improving the compatibility of the expanded vermiculite powder and ABS, and reducing the molecular weight of the expanded vermiculite powder and waterThe branching structure of the hyperbranched dispersant enables the expanded vermiculite powder to be dispersed more uniformly while the hydration ability is achieved, the dispersion degree of the expanded vermiculite powder on the surface of the ABS resin can be improved, the surface defect is effectively overcome, and the surface glossiness of the ABS material is improved. In the combustion process of the flame retardant material, the contact area between expanded vermiculite powder covered on the surface of the ABS resin and flame is increased, and the expanded vermiculite powder with a fine air spacing layer can reduce heat transfer to the ABS resin, so that the flame retardant effect is improved.

1)

2)

3)ABS-g-MAH+M(OH)_z→ABS-g-COO-M+H₂O

Wherein M is Mg, Fe or Al, and R-OH are hyperbranched dispersants containing hydroxyl.

Compared with the prior art, the invention has the following beneficial effects:

aiming at the problems of poor dispersion, easy generation of pits, low glossiness and stable flame retardant effect of the conventional expanded vermiculite powder modified flame retardant ABS material, the invention introduces a hyperbranched dispersant to carry out organic pretreatment on the expanded vermiculite powder, adds a compatilizer to improve the compatibility of the expanded vermiculite powder with the ABS resin and a flame retardant, improves the surface dispersion degree of the expanded vermiculite powder ABS resin by virtue of a branched structure of the hyperbranched dispersant, and solves the problems of low glossiness and unstable flame retardant effect of the flame retardant ABS material. The process is simple, the control is easy, the requirement on equipment is not high, the used equipment is general polymer processing equipment, the investment is not high, and the prepared flame-retardant ABS material has excellent flame retardant property, good glossiness and heat resistance and high fluidity. The expanded vermiculite powder modified flame-retardant ABS material prepared by the invention has good flame-retardant property, heat resistance, higher material glossiness and high fluidity, and can be widely applied to plastic products such as electronic and electrical components, instrument shells and the like.

Drawings

FIG. 1 is a flow chart of a preparation process of the expanded vermiculite powder modified flame-retardant ABS material.

Detailed Description

In order that the invention may be more readily understood, reference will now be made to the following more particular description of the invention, examples of which are set forth below. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. These embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The invention provides a modified flame-retardant ABS material which is characterized by being prepared from the following raw materials in parts by weight: 60-76 parts of ABS resin; 14-20 parts of bromotriazine; 4-6 parts of antimony trioxide; 2-6 parts of a compatilizer; 4-8 parts of organic expanded vermiculite powder; 0.2-0.4 part of a lubricant; 0.4-0.6 part of antioxidant; 0.1-0.3 part of anti-dripping agent.

Preferably, the composition is prepared from the following raw materials in parts by weight: 65-71 parts of ABS resin; 16-18 parts of bromotriazine; 4-6 parts of antimony trioxide; 3-5 parts of a compatilizer; 5-7 parts of organic expanded vermiculite powder; 0.2-0.4 part of a lubricant; 0.4-0.6 part of antioxidant; 0.1-0.3 part of anti-dripping agent.

More preferably, the compound is prepared from the following raw materials in parts by weight: 67-69 parts of ABS resin; 16.5-17.5 parts of bromotriazine; 4.5-5.5 parts of antimony trioxide; 3.5-4.5 parts of a compatilizer; 5.5-6.5 parts of organic expanded vermiculite powder; 0.2-0.3 part of lubricant; 0.35-0.45 part of antioxidant; 0.2-0.3 part of anti-dripping agent.

Wherein the organic expanded vermiculite powder is organically treated by hyperbranched dispersant of hyperbranched polyester or hyperbranched dispersant of dendritic polyamidoamine.

Preferably, the hyperbranched dispersant is one or a combination of two of a hyperbranched dispersant containing a terminal hydroxyl group and a hyperbranched dispersant containing a terminal amino group.

Optionally, the hydroxyl-terminated hyperbranched dispersant is selected from hyperbranched polyesters or dendritic polyamidoamines; the hyperbranched dispersant containing terminal amino groups is selected from hyperbranched dispersants of dendritic polyamidoamines.

Preferably, the compatilizer is one or a combination of maleic anhydride grafted ABS, maleic anhydride and styrene copolymer SMA. More preferably, the compatilizer is styrene copolymer SMA, and the compatilizer is styrene copolymer SMA. The main chain part of ABS or polystyrene chain segment in the compatilizer has good compatibility with ABS, and maleic anhydride with high active group in the compatilizer can react with hydroxyl or amino in the hyperbranched dispersant to form covalent bond, so that the interface strength of ABS resin and expanded vermiculite powder is improved, and the thickness and the adhesive force of a phase interface are improved, thereby improving the mechanical property and the gloss of the material, but excessive addition of the compatilizer can cause the viscosity of the material to be increased and the melt index to be reduced.

Preferably, the anti-dripping agent is polytetrafluoroethylene coated by a methyl methacrylate-styrene copolymer.

Preferably, the lubricant is ethylene bis stearamide or magnesium stearate.

Preferably, the antioxidant comprises a main antioxidant and an auxiliary antioxidant, wherein the main antioxidant is beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid octadecyl ester; the auxiliary antioxidant is tris (2, 4-di-tert-butyl) phenyl phosphite. The antioxidant is a compound of a main antioxidant beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) octadecyl propionate and an auxiliary antioxidant tris (2, 4-di-tert-butyl) phenyl phosphite. Preferably, the primary and secondary antioxidants are present in a ratio of 1: (0.5-1.5), and further preferably 1: 1.

The preparation method of the modified flame-retardant ABS material is characterized by comprising the following steps: (1) taking expanded vermiculite powder, adding a hyperbranched dispersant, and stirring and mixing on a high-speed stirrer under the condition of heating to obtain organic expanded vermiculite powder; (2) mixing ABS resin, bromotriazine, antimony trioxide, a compatilizer, organic expanded vermiculite powder, a lubricant, an antioxidant and an anti-dripping agent on a high-speed mixer according to the weight parts of the raw materials of any one of claims 1 to 6; (3) and (3) putting the uniformly mixed raw materials in the step (2) into a parallel double-screw extruder, and granulating after melt extrusion.

Preferably, the proportion of the expanded vermiculite powder and the hyperbranched dispersant in the step (1) is as follows: taking 100 parts of expanded vermiculite powder, and adding 4.5-5.5 parts of hydroxyl-terminated hyperbranched dispersant. Preferably, the heating condition is 85-90 ℃. Preferably, when the high-speed stirrer is used for stirring and mixing, the rotating speed of the stirrer is told to be 380-420 rpm; the treatment time is 14-16 min.

Preferably, the process parameters of step (3) are as follows: the temperature of the first zone is 180-200 ℃, the temperature of the second zone is 185-205 ℃, the temperature of the third zone is 190-210 ℃, the temperature of the fourth zone is 185-205 ℃, the temperature of the fifth zone is 185-205 ℃, the temperature of the sixth zone is 185-205 ℃, the temperature of the seventh zone is 180-200 ℃, the temperature of the eighth zone is 180-200 ℃, the temperature of a machine head is 200-220 ℃, the rotating speed of a double-screw extruder is set to be 300-600 rpm, and the vacuum degree is set to be-0.04-0.06 MPa.

More preferably, the process parameters of step (3) are: the temperature of the first zone is 180-190 ℃, the temperature of the second zone is 185-195 ℃, the temperature of the third zone is 190-200 ℃, the temperature of the fourth zone is 185-195 ℃, the temperature of the fifth zone is 185-195 ℃, the temperature of the sixth zone is 185-195 ℃, the temperature of the seventh zone is 180-190 ℃, the temperature of the eighth zone is 180-190 ℃, the temperature of the machine head is 200-210 ℃, the rotating speed of the double-screw extruder is set to be 400-500 rpm, and the vacuum degree is set to be-0.04-0.06 MPa.

Preferably, the screw of the parallel double-screw extruder is in a double-thread shape, the lead of the double-thread screw is large, the retention time of materials during extrusion is short, the degradation of the materials is reduced, the production efficiency is improved, and meanwhile, the plasticizing and dispersing capacity of the double-thread screw is stronger than that of a single-thread screw, so that the dispersing degree of the flame retardant is improved. Too large length-diameter ratio of the screw can cause that the heating time of the polymer becomes long, the flame retardant is degraded, the manufacturing and installation of the screw and the extruder are increased, the length-diameter ratio of the screw is too small, the dispersing capacity is poor, the production efficiency is not favorably improved, and the preferred ratio L/D of the length L of the screw to the diameter D of the screw is 35-45. When a parallel double-screw extruder is adopted, the anti-dripping agent in the raw material components is fiberized under the shearing action of an extruding screw to form a net structure in the material, and the material is heated and shrunk to prevent the material from melting and dripping during combustion, so that the flame retardance of the material can be improved.

The specific information of each raw material used in the examples of the present invention and the comparative examples is as follows:

ABS resin: selected from Ningbo le Jinyunhxing chemical Co., Ltd.

Expanded vermiculite powder: selected from Xinfa mining company, Inc., Linshou county, Hebei province.

Non-expanded vermiculite powder: selected from Xinfa mining company, Inc., Linshou county, Hebei province.

Anti-dripping agent: selected from Guangzhou entropy Innovative materials, Inc.

Antioxidant: the primary antioxidant is octadecyl beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate, and the secondary antioxidant is tris (2, 4-di-tert-butyl) phenyl phosphite, and is selected from Santa Laketchup, Guangzhou.

Lubricant: selected from XUEGANTAI chemical Co Ltd

Superfine talcum powder: selected from the group consisting of Heizhou Ustamen chemical Co., Ltd.

Hyperbranched dispersant containing terminal hydroxyl groups or terminal amino groups: a hyperbranched dispersant selected from hyperbranched polyesters or dendritic polyamidoamines of Waishaham molecular New materials, Inc.