CN113583351B

CN113583351B - High-temperature-resistant flame-retardant material and preparation method and application thereof

Info

Publication number: CN113583351B
Application number: CN202110879460.6A
Authority: CN
Inventors: 谢君; 孙兴旺; 赵培
Original assignee: Wuxi Aosheng New Material Technology Co ltd
Current assignee: Wuxi Aosheng New Material Technology Co ltd
Priority date: 2021-08-02
Filing date: 2021-08-02
Publication date: 2023-02-03
Anticipated expiration: 2041-08-02
Also published as: CN113583351A

Abstract

The invention discloses a high-temperature-resistant flame-retardant material, and a preparation method and application thereof, and belongs to the technical field of materials. The preparation raw materials comprise, by weight, 5-15 parts of terpolymer-diene, 4-8 parts of high-density polyethylene, 5-12 parts of low-melt-index block copolymer polypropylene, 2-8 parts of plasticizer, 10-16 parts of flame retardant, 0.3-0.7 part of dispersant, 0.8-1.4 parts of antioxidant, 0.2-0.8 part of colorant and the like. The material has strong high temperature resistance and flame retardant property, and the product prepared by the material, especially the automobile motor cover, can effectively maintain the shape of the product under the condition of 96h treatment at 130 ℃ or 200h treatment at 120 ℃, has high aging resistance and can reach A0 flame retardant standard. The preparation method of the high-temperature resistant flame-retardant material is simple and easy to operate. The corresponding preparation method of the automobile motor cover does not need foaming, only needs one mould, and can reduce waste and labor input.

Description

High-temperature-resistant flame-retardant material and preparation method and application thereof

Technical Field

The invention relates to the technical field of materials, and particularly relates to a high-temperature-resistant flame-retardant material, and a preparation method and application thereof.

Background

The motor cover is an important component on an automobile motor product, and is mainly used for accommodating the motor to play a certain protection role on the motor.

But the motor cover that automobile field generally used is relatively poor in high temperature resistance, can't satisfy the increasingly high temperature resistant requirement of present automobile motor cover, and simultaneously, the motor cover flame retardant efficiency who generally is suitable for at present is not good.

In view of this, the invention is particularly proposed.

Disclosure of Invention

One of the objectives of the present invention is to provide a high temperature resistant flame retardant material, which can simultaneously achieve better high temperature resistant and flame retardant effects.

The second purpose of the invention is to provide a preparation method of the high-temperature resistant flame-retardant material.

The invention also aims to provide application of the high-temperature-resistant flame-retardant material.

The invention also aims to provide the automobile motor cover made of the high-temperature-resistant flame-retardant material.

The invention can be realized as follows:

according to the first aspect, the invention provides a high-temperature-resistant flame-retardant material, which comprises, by weight, 5-15 parts of terpolymer-diene, 4-8 parts of high-density polyethylene, 5-12 parts of low-melt-index block copolymer polypropylene, 2-8 parts of a plasticizer, 10-16 parts of a flame retardant, 0.3-0.7 part of a dispersing agent, 0.8-1.4 parts of an antioxidant, 0.2-0.8 part of a coloring agent, 2-4 parts of a coupling agent, 1-3 parts of a lubricant and 45-55 parts of a filler.

In a preferred embodiment, the preparation raw material comprises 8-12 parts of terpolymer-diene, 5-7 parts of high-density polyethylene, 6-10 parts of low-melting-index block copolymer polypropylene, 4-6 parts of plasticizer, 12-15 parts of flame retardant, 0.4-0.6 part of dispersing agent, 0.9-1.2 parts of antioxidant, 0.4-0.6 part of coloring agent, 2.5-3.5 parts of coupling agent, 1.5-2.5 parts of lubricating agent and 48-52 parts of filler.

In a more preferred embodiment, the raw materials for preparation include 10 parts of terpolymer-diene, 6 parts of high density polyethylene, 8 parts of low melt index block copolymer polypropylene, 5 parts of plasticizer, 14 parts of flame retardant, 0.5 part of dispersant, 1 part of antioxidant, 0.5 part of colorant, 3 parts of coupling agent, 2 parts of lubricant and 50 parts of filler.

In an alternative embodiment, the terpolymer-diene includes at least one of designations 4725P, 1703P, 3702, 5601, 7001, and 9301.

In an alternative embodiment, the high density polyethylene comprises at least one of designations 5200B, 5301B, 5000S, 3300F, 6000F, MH, MH602 and MH 702.

In an alternative embodiment, the low melt index block co-polypropylene comprises at least one of the designations T30S, PP022, HP550J, F501, H5300, K8003, Y-130, F79S, 3365, and 5014.

In an alternative embodiment, the flame retardant comprises at least one of an inorganic flame retardant and a halogen-based flame retardant.

In an alternative embodiment, the flame retardant is an inorganic flame retardant.

In an alternative embodiment, the inorganic flame retardant comprises at least one of aluminum hydroxide and magnesium hydroxide.

In a preferred embodiment, the flame retardant comprises aluminum hydroxide and magnesium hydroxide in a weight ratio of 1.8 to 1.2.

In a more preferred embodiment, the aluminum hydroxide comprises at least one of the designations Space Rite S-3, space Rite S-11, and Space Rite S-23, or the magnesium hydroxide comprises at least one of the designations magshield S and magshield M.

In an alternative embodiment, the dispersant comprises at least one of stearic acid and calcium stearate.

In a preferred embodiment, the dispersant comprises stearic acid and calcium stearate in a weight ratio of 0.25 to 0.2 to 0.3.

In a more preferred embodiment, the stearic acid comprises at least one of the designations 1830, 1831, 1838, and 1839, or the calcium stearate comprises at least one of the designations BS-3818 and CSP-501.

In an alternative embodiment, the plasticizer comprises polyethylene wax; more preferably, the polyethylene wax comprises at least one of the designations 100, 200, 300, and 500.

In an alternative embodiment, the antioxidant comprises at least one of designations 168/1010, 215, and 225.

In an alternative embodiment, the colorant comprises carbon black.

In a preferred embodiment, the carbon black includes at least one of the designations N219, N220, N231, and N299.

In an alternative embodiment, the coupling agent comprises a silane coupling agent.

In a preferred embodiment, the silane coupling agent includes at least one of grades KH530, KH570, KH792, KH561, KH560, KH550, KH470, a186, a174, a1120, a1871, a187, and a 1100.

In an alternative embodiment, the lubricant comprises a white oil, preferably a technical grade white oil.

In a preferred embodiment, the technical white oil comprises at least one of the

designations

3, 5, 7, 10, 15, 32, and 68.

In an alternative embodiment, the filler comprises at least one of calcium carbonate and barium sulfate.

In a preferred embodiment, the mesh size of the filler is 350-450 mesh.

In a second aspect, the present invention provides a method for preparing a high temperature resistant flame retardant material according to any of the previous embodiments, comprising the steps of: and extruding and molding the preparation raw materials mixed according to the proportion in an extruder.

In alternative embodiments, extrusion molding is performed using a combination of twin screw and single screw or a combination of twin screw and melt rod.

In an optional embodiment, the extrusion molding adopts a mode of combining a double screw and a single screw, the double screw is provided with 6 temperature zones, the temperature of the first temperature zone and the second temperature zone is 155-165 ℃, the temperature of the sixth temperature zone is 85-95 ℃, and the temperature of the rest temperature zones is 120-140 ℃; the working temperature of the single screw is 90-120 ℃.

In a preferred embodiment, the temperature of the first and second temperature zones of the twin screw is 160 ℃, the temperature of the sixth temperature zone is 90 ℃ and the temperature of the remaining temperature zones is 120 to 130 ℃.

In an alternative embodiment, the pressure between the vacuum venting section and the melt pump during the twin-screw extrusion is 1.7-2.2MPa.

In an alternative embodiment, extrusion molding further comprises cooling the extruded material.

In an alternative embodiment, the current of the motor corresponding to the cooling roller is 95-115A during the cooling process.

In an alternative embodiment, the cooling process comprises three cooling stages, the cooling temperatures of the three cooling stages being 55-65 ℃, 38-42 ℃ and 25-35 ℃ respectively, and the cooling times of the three cooling stages being 5-10s, 15-20s and 55-65s respectively.

In a third aspect, the present invention provides the use of a high temperature resistant flame retardant material according to any of the preceding embodiments, for example in an automobile, air conditioning, high-speed rail or building.

In an alternative embodiment, the high temperature resistant flame retardant material is used to make an automotive motor cover.

In a fourth aspect, the invention provides an automobile motor cover which is made of the high-temperature-resistant flame-retardant material in any one of the previous embodiments.

In a fifth aspect, the present invention provides a method for manufacturing an automobile motor cover according to any one of the previous embodiments, including the steps of: the high temperature resistant flame retardant material of the foregoing embodiment is molded into a desired shape in a mold of an automobile motor cover.

In an alternative embodiment, the number of moulds is 1.

In an alternative embodiment, the temperature at the edges of the mold is higher than the temperature in the middle of the mold.

The beneficial effect of this application includes:

according to the preparation method, the terpolymer-diene, the high-density polyethylene, the low-melting-index block copolymer polypropylene, the plasticizer, the flame retardant, the dispersant, the antioxidant, the coloring agent, the coupling agent, the lubricant and the filler are matched according to the proportion provided by the application, so that the obtained material has high temperature resistance and flame retardance, the product prepared by the preparation method, especially an automobile motor cover, can effectively maintain the shape of the product under the condition of 96h treatment at 130 ℃ or 200h treatment at 120 ℃, has high ageing resistance and can reach the A0 flame retardance standard. The preparation methods of the high-temperature-resistant flame-retardant material and the automobile motor cover are simple, easy to operate and suitable for industrial production.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIGS. 1 to 10 are graphs showing the performance test of each test sample in test example 1 in terms of flame retardancy, breaking, right-angle tearing, pant-type tearing, hardness, and heat shrinkage;

fig. 11 to 19 are graphs showing performance tests in terms of heat aging resistance, cold heat exchanger resistance, low temperature impact resistance and high temperature resistance of each test sample in test example 2.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The high temperature resistant flame retardant material provided by the present application, and the preparation method and application thereof are specifically described below.

The application provides a high-temperature-resistant flame-retardant material which comprises, by weight, 5-15 parts of terpolymer-diene, 4-8 parts of high-density polyethylene, 5-12 parts of low-melting-index block copolymer polypropylene, 2-8 parts of a plasticizer, 10-16 parts of a flame retardant, 0.3-0.7 part of a dispersing agent, 0.8-1.4 parts of an antioxidant, 0.2-0.8 part of a coloring agent, 2-4 parts of a coupling agent, 1-3 parts of a lubricant and 45-55 parts of a filler.

The terpolymer-diene may, for example, be 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, or 15 parts, or any other weight parts in the range of 5 to 15 parts.

The high density polyethylene may be 4 parts, 4.5 parts, 5 parts, 5.5 parts, 6 parts, 6.5 parts, 7 parts, 7.5 parts, 8 parts, or the like, or may be any other value within the range of 4 to 8 parts by weight.

The low melt index block copolymer polypropylene may be 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, etc., and may be any other value within the range of 5 to 12 parts by weight.

The plasticizer may be present in an amount of 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, 5 parts, 5.5 parts, 6 parts, 6.5 parts, 7 parts, 7.5 parts, 8 parts, or the like, or any other amount ranging from 2 to 8 parts by weight.

The flame retardant may be 10 parts, 10.5 parts, 11 parts, 11.5 parts, 12 parts, 12.5 parts, 13 parts, 13.5 parts, 14 parts, 14.5 parts, 15 parts, 15.5 parts, 16 parts or the like, and may be any other number of parts by weight within the range of 10 to 16 parts.

The dispersant may be 0.3 parts, 0.35 parts, 0.4 parts, 0.45 parts, 0.5 parts, 0.55 parts, 0.6 parts, 0.65 parts, 0.7 parts, or the like, or may be any other value within the range of 0.3 to 0.7 parts by weight.

The antioxidant may be 0.8 parts, 0.85 parts, 0.9 parts, 0.95 parts, 1 part, 1.05 parts, 1.1 parts, 1.15 parts, 1.2 parts, 1.25 parts, 1.3 parts, 1.35 parts, 1.4 parts, etc., or may be any other value within the range of 0.8 to 1.4 parts by weight.

The colorant may be 0.2 parts, 0.25 parts, 0.3 parts, 0.35 parts, 0.4 parts, 0.45 parts, 0.5 parts, 0.55 parts, 0.6 parts, 0.65 parts, 0.7 parts, 0.75 parts, 0.8 parts, or the like, and may be any other weight part value within the range of 0.2 to 0.8 parts.

The coupling agent may be present in an amount of 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, etc., or any other amount within the range of 2 to 4 parts by weight.

The lubricant may be 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, etc., and may be any other weight part value within the range of 1 to 3 parts.

The filler can be 45 parts, 46 parts, 47 parts, 48 parts, 49 parts, 50 parts, 51 parts, 52 parts, 53 parts, 54 parts or 55 parts, and the like, and can also be any other weight part value within the range of 45-55 parts.

It should be noted that the components provided in the present application can be freely combined within the above ranges, but the total weight of the combined components is preferably 100 parts, and further, the case where other materials can be additionally added is not excluded.

In this application, the terpolymer-diene (EPDM) may also be referred to as "ethylene-propylene-nonconjugated diene terpolymer" which has the characteristics of high temperature resistance and corrosion resistance. In a preferred embodiment, the terpolymer-diene used herein includes at least one of designations 4725P, 1703P, 3702, 5601, 7001, and 9301. By adopting the synthetic terpolymer-diene with the grade, the service life is longer than that of the traditional natural rubber EPDM, and the EPDM can resist the temperature of 175 ℃.

High Density Polyethylene (HDPE) is mainly used to help increase the ductility and strength of the product, and to regulate and cushion the balance between the stiffness and toughness of the material. It is worth mentioning that the use of only low melt index block copolymer polypropylene instead of high density polyethylene in the preparation of the raw material results in a material with high strength (rigidity) and brittle toughness, which is prone to cracking. In a preferred embodiment, the high density polyethylene used herein comprises at least one of designations 5200B, 5301B, 5000S, 3300F, 6000F, MH502, MH602, and MH 702.

Low melt index block copolymer polypropylene is obtained by polymerizing ethylene after removing unreacted propylene after the polymerization of propylene alone, and is actually a mixture of polypropylene, polyethylene and a terminal block copolymer, which on the one hand can have a certain degree of rigidity and on the other hand improves the impact resistance (especially low temperature impact resistance) of polypropylene. In a preferred embodiment, the low melt index block copolymer polypropylene used herein comprises at least one of the designations T30S, PP022, HP550J, F501, H5300, K8003, Y-130, F79S, 3365, and 5014. The low-melt-index block copolymerization polypropylene can be effectively combined with EPDM and high-density polyethylene and rearranged molecular chains, so that the strength of the material is improved.

Herein, the plasticizer includes polyethylene wax. In a preferred embodiment, the polyethylene wax used herein comprises at least one of the designations 100, 200, 300, and 500. It is worth noting that the plasticizer in the application can not adopt the common plasticizer for injection molding, otherwise the plastic uptake molding requirement required by the application can not be met.

The flame retardant may include at least one of an inorganic flame retardant and a halogen-based flame retardant. In a preferred embodiment, the flame retardant is an inorganic flame retardant, specifically including at least one of aluminum hydroxide and magnesium hydroxide. By reference, the flame retardant comprises aluminum hydroxide and magnesium hydroxide in a weight ratio of 1.8 to 1.2 (e.g. 1. In a preferred embodiment, the aluminum hydroxide used herein includes at least one of the trade designations of Space Rite S-3, space Rite S-11, and Space Rite S-23, and the magnesium hydroxide includes at least one of the trade designations of Magshield S and Magshield M.

The flame resistance of the material can be effectively improved under the condition of lower cost by taking the aluminum hydroxide and the magnesium hydroxide as the flame retardant, and the high-temperature resistant flame retardant material finally obtained can meet the requirement of A-0 flame retardant grade by matching the aluminum hydroxide and the magnesium hydroxide according to the proportion and matching with other raw materials; on one hand, the adoption of the halogen flame retardant can greatly increase the production cost and reduce the economic benefit, and on the other hand, the flame retardant effect can only meet the requirement of fire leaving to extinguishing in conventional unit time. Specifically, the traditional automobile industry requires that the automobile is ignited and extinguished within 100 seconds, most of materials at corresponding parts of the existing automobile can only realize the ignition and extinguishment within 70-80 seconds, and the materials provided by the application can realize the ignition and extinguishment within 15 seconds.

Herein, the dispersant may include at least one of stearic acid and calcium stearate. By reference, the dispersant comprises stearic acid and calcium stearate in a weight ratio of 0.25 to 0.3 (e.g., 0.25. In a preferred embodiment, stearic acid includes at least one of the designations 1830, 1831, 1838, and 1839 and calcium stearate includes at least one of the designations BS-3818 and CSP-501.

In the present application, the antioxidant may include at least one of 168/1010 (where "168/1010 means that the oxidant 168 and the oxidant 1010 are compounded"), 215 and 225, that is, the antioxidant used in the present application is a compound antioxidant. In normal environment, ultraviolet irradiation or high temperature and the vibration etc. that the car produced at the normal driving in-process all can accelerate the material ageing, and some oxygen of anti-oxidant in this application can the separation, play the dispersion and carry out the effect protected to the outer layer, avoid outer material to take place to decompose and redox reaction, effectively prolong the life-span of material.

In the present application, the colorant may include carbon black, and further, other colorants may be used as needed. In a preferred embodiment, the carbon black includes at least one of the designations N219, N220, N231, and N299.

In the present application, the coupling agent includes a silane coupling agent, which mainly plays a role of coupling and plasticizing. In a preferred embodiment, the silane coupling agent includes at least one of grades KH530, KH570, KH792, KH561, KH560, KH550, KH470, a186, a174, a1120, a1871, a187, and a 1100.

In the present application, the lubricant may comprise a white oil, preferably a technical grade white oil. In a preferred embodiment, the technical white oil comprises at least one of the

designations

3, 5, 7, 10, 15, 32, and 68. The lubricant can prevent the shearing force of the material from being too high and reduce the friction force.

In the present application, the filler may include at least one of calcium carbonate and barium sulfate, which are mainly used to control the density and the molding condition of the material. In a preferred embodiment, the mesh size of the filler is 350-450 mesh (preferably 400 mesh). The calcium carbonate and the barium sulfate with the meshes can effectively improve the toughness and the ductility of the material. It is worth noting that the mesh number of the filler directly affects the plasticizing effect, and if the mesh number is too small, the plasticizing effect is poor due to the larger unit particle size, so that the toughness and ductility of the material are greatly reduced.

It is to be noted that the above-mentioned raw materials of the present application are commercially available.

Correspondingly, the application also provides a preparation method of the high-temperature-resistant flame-retardant material, which comprises the following steps: and extruding and molding the preparation raw materials mixed according to the proportion in an extruder.

The above mixing process can be performed by mechanical stirring, the stirring power can be 60-70KW, such as 60KW, 65KW or 70KW, etc., and the stirring time is preferably at least 5min, more preferably 5-10min, such as 5min, 6min, 7min, 8min, 9min or 10min.

By mixing the raw materials under the conditions, the raw materials can be fully and uniformly mixed, and the subsequent extrusion molding is facilitated.

In reference, the extrusion molding can adopt a mode of combining a double screw and a single screw, so that the defects of high loss and frequent replacement of parts can be avoided.

When extrusion molding is performed by combining a twin screw and a single screw, the twin screw has 6 temperature zones, the temperature of the first temperature zone and the second temperature zone is 155 to 165 ℃ (e.g., 155 ℃, 160 ℃, 165 ℃, etc.), the temperature of the sixth temperature zone is 85 to 95 ℃ (e.g., 85 ℃, 90 ℃, 95 ℃, etc.), and the temperature of the remaining temperature zones is 120 to 140 ℃ (e.g., 120 ℃, 125 ℃, 130 ℃, 135 ℃, 140 ℃, etc.).

In a preferred embodiment, the twin-screw first and second temperature zones have a temperature of 160 ℃, the sixth temperature zone has a temperature of 90 ℃ and the remaining temperature zones have a temperature of 125 ℃.

The working temperature of the single screw is 90-120 ℃ (such as 90 ℃, 95 ℃, 100 ℃, 115 ℃ or 120 ℃ and the like).

It is worth noting that the working temperature of the extrusion molding process described above in the present application is specifically set according to the specific raw material formula provided in the present application. If the temperature is too high, on one hand, the material is easily carbonized, so that the shearing heat of a material beating block and a plasticizing block in a screw rod is higher in the extrusion process, the viscosity of the material is increased, the resistance is increased, the situations of blockage, uneven discharging and material loss occur during discharging, and the loss rate is high; on the other hand, the material is easy to age in advance, and the subsequent process cannot be effectively carried out. If the temperature is too low, the material is likely to be incapable of physical melting, that is, incapable of being pushed and extruded forward in a colloidal state.

In an alternative embodiment, the pressure between the vacuum venting section and the melt pump during the twin screw extrusion process is 1.7 to 2.2MPa, such as 1.7MPa, 1.8MPa, 1.9MPa, 2MPa, 2.1MPa, or 2.2MPa, and the like. The solution pump is positioned between the vacuum exhaust section and the metering section.

By setting the pressure between the vacuum exhaust section and the melt pump in the above range, the pressure caused by excessive pressure can be avoided: firstly, materials are carbonized and agglomerated, so that discharge blockage and unstable discharge are caused, and the molding condition of products cannot be ensured; secondly, motor burning is caused after the motor runs under high load, and it is worth mentioning that the "burning" mentioned here has very important economic impact on the actual processing production, which at least results in the economic loss calculated by 10W.

Furthermore, in the preparation process, the extrusion equipment is externally connected with 2 vacuum pumps, the pressure of the vacuum pumps is about 0.08-0.095MPa, so that volatile substances, impurities and moisture generated by the raw materials in the preparation process are sucked out in the extrusion forming process, and the moisture content of the materials is reduced to be almost 0.

Further, the extruded material is cooled.

In reference, the current of the motor corresponding to the cooling roller can be set to 95-115A, such as 95A, 100A, 105A, 110A or 115A, during the cooling process.

In the present application, the cooling process comprises three cooling stages, wherein the cooling temperatures of the three cooling stages are 55-65 ℃ (preferably 60 ℃), 38-42 ℃ (preferably 40 ℃) and 25-35 ℃ (preferably 30 ℃), and the cooling times of the three cooling stages are 5-10s (such as 5s, 6s, 7s, 8s, 9s or 10s, etc.), 15-20s (such as 15s, 16s, 17s, 18s, 19s or 20s, etc.) and 55-65s (such as 55s, 58s, 60s, 62s or 65s, etc.), respectively.

If the cooling time is too short, the material is easy to have insufficient cooling rate, large shrinkage rate and incomplete annealing, so that the polarity of the surface of the material is large, and the performance of a finished product is influenced; the cooling time is too long, and the production and production efficiency is easily reduced.

In summary, by combining the preparation process provided by the application after the raw materials are mixed according to the application, the high-temperature-resistant flame-retardant material which can effectively maintain the shape of the product under the condition of processing at 130 ℃ for 96 hours or processing at 120 ℃ for 200 hours, has high aging resistance and can reach the flame-retardant standard of A0 can be obtained.

It should be noted that the extrusion molding process and conditions not mentioned in the present application can refer to the prior art, and are not described herein in detail.

In addition, the application also provides the application of the high-temperature resistant flame retardant material, for example, the high-temperature resistant flame retardant material can be used in automobiles (such as automobile motor covers or automobile interiors and the like), air conditioners, high-speed rails or buildings (such as building sound insulation plates), and especially in the preparation process of automobile motor covers.

Correspondingly, the application also provides an automobile motor cover which is made of the high-temperature-resistant flame-retardant material.

Further, the application also provides a preparation method of the automobile motor cover, which comprises the following steps: and (3) forming the high-temperature-resistant flame-retardant material into a required shape in a mold of an automobile motor cover.

Specifically, the motor cover is formed by cutting a plate after extrusion forming and then forming the motor cover through a die.

It is worth explaining that the high-temperature-resistant flame-retardant material provided by the application can be formed by only adopting 1 mold, and the temperature of the mold presents a valley type temperature curve with the temperatures at two sides higher than the middle temperature. The reason why the material for preparing the motor cover provided by the prior art needs to be molded into the motor cover by simultaneously using 2 molds (upper and lower matched molds) is that the preparation process provided by the application can meet the plastic uptake requirement of the material, so that the mold pressing is not needed. In addition, the foaming process in the prior art has still been avoided in the preparation process of this application, has reduced extravagant and artifical the input.

The features and properties of the present invention are described in further detail below with reference to examples.

Example 1

The embodiment provides a high-temperature resistant flame-retardant material, which is obtained through the following steps:

10 parts of terpolymer-diene (No. 4725P), 6 parts of high density polyethylene (No. 5000S), 8 parts of low melt index block copolymer polypropylene (No. K8003), 5 parts of plasticizer (No. 100# polyethylene wax), 14 parts of flame retardant (consisting of Space Rite S-3 aluminum hydroxide and magshield S magnesium hydroxide in a weight ratio of 5:7), 0.5 part of dispersant (consisting of 1830 stearic acid and BS-3818 calcium stearate in a weight ratio of 1:1), 1 part of antioxidant (No. 168/1010), 0.5 part of colorant (N219 carbon black), 3 parts of coupling agent (KH 530 silane coupling agent), 2 parts of lubricant (3 # technical grade white oil) and 50 parts of filler (400 mesh calcium carbonate) were mixed under a mechanical stirring condition of 65KW for 5min.

And extruding and molding the mixed raw materials by adopting a mode of combining a double screw and a single screw to obtain the high-temperature-resistant flame-retardant material.

The process conditions involved in the extrusion molding include:

the twin screw has 6 temperature zones, the first temperature zone and the second temperature zone are 160 ℃, the sixth temperature zone is 90 ℃, and the rest temperature zones are 125 ℃. The operating temperature of the single screw was 120 ℃.

In the process of double-screw extrusion, the pressure between a vacuum exhaust section and a melt pump is 2MPa, and the pressure of 2 vacuum pumps externally connected with the extrusion equipment is 0.09MPa.

And cooling the extruded material, wherein the current of a motor corresponding to the cooling roller is 110A, the cooling temperature of the three cooling stages is 60 ℃, 40 ℃ and 30 ℃, and the cooling time is 10s, 20s and 60s respectively.

Example 2

This example differs from example 1 only in the amounts of the ingredients used, and the specific materials used and the preparation conditions for each ingredient are the same as in example 1.

The high-temperature resistant flame retardant material in the embodiment is prepared from the following raw materials in parts by weight:

8 parts of terpolymer-diene, 7 parts of high-density polyethylene, 10 parts of low-melt-index block copolymer polypropylene, 4 parts of plasticizer, 15 parts of flame retardant, 0.4 part of dispersant, 1.2 parts of antioxidant, 0.4 part of colorant, 2.5 parts of coupling agent, 1.5 parts of lubricant and 58 parts of filler.

Example 3

This example differs from example 1 only in the amount of each ingredient used, and the specific materials and preparation conditions used for each ingredient are the same as in example 1.

12 parts of terpolymer-diene, 5 parts of high-density polyethylene, 6 parts of low-melt-index block copolymer polypropylene, 6 parts of plasticizer, 12 parts of flame retardant, 0.6 part of dispersant, 0.9 part of antioxidant, 0.6 part of colorant, 3.5 parts of coupling agent, 2.5 parts of lubricant and 48 parts of filler.

Example 4

15 parts of terpolymer-diene, 8 parts of high-density polyethylene, 12 parts of low-melt-index block copolymer polypropylene, 8 parts of plasticizer, 16 parts of flame retardant, 0.7 part of dispersant, 1.4 parts of antioxidant, 0.8 part of colorant, 4 parts of coupling agent, 3 parts of lubricant and 55 parts of filler.

Example 5

5 parts of terpolymer-diene, 4 parts of high-density polyethylene, 5 parts of low-melt-index block copolymer polypropylene, 2 parts of plasticizer, 10 parts of flame retardant, 0.3 part of dispersant, 0.8 part of antioxidant, 0.2 part of colorant, 2 parts of coupling agent, 1 part of lubricant and 45 parts of filler.

Example 6

The present example differs from example 1 in that:

the grade of the terpolymer-diene is 3702, the grade of the high-density polyethylene is 5000S, the grade of the low-melting-index block copolymer polypropylene is T30S, the grade of the polyethylene wax is 200#, the grade of the aluminum hydroxide is S-11, the grade of the magnesium hydroxide is M (the weight ratio of the aluminum hydroxide to the magnesium hydroxide is 1.

Example 7

This example differs from example 1 in that:

the terpolymer-diene grade is 5601, the high density polyethylene grade is 6000F, the low melt index block copolymerized polypropylene grade is HP550J, the polyethylene wax grade is 300#, the aluminum hydroxide grade is S-23, the magnesium hydroxide grade is Magshield S (the weight ratio of the aluminum hydroxide to the magnesium hydroxide is 1.2), the stearic acid grade is 1838, the calcium stearate grade is CSP-501 (the weight ratio of the stearic acid to the calcium stearate is 0.25 to 0.3), the antioxidant grade is 225, the carbon black grade is N231, the coupling agent grade is A189, the industrial grade white oil grade is 7, and the filler is barium sulfate.

Example 8

This example differs from example 1 in that:

terpolymer-diene grades 7001 and 9301 (weight ratio 1:1), high density polyethylene grades 5301B and MH502 (weight ratio 1:1), low melt index block copolymer polypropylene grades F501 and H5300 (weight ratio 1:1), polyethylene wax grades 500# and 100# (weight ratio 1:1), aluminum hydroxide grades Space Rite S-23 and Space Rite S-11 (weight ratio 1:1), magnesium hydroxide grades magshift S and magshift M (weight ratio 3257 zxft 5657), stearic acid grades 1839 and 1830 (weight ratio 3264 zxft 5664), calcium stearate grades BS-3818 and CSP501 (weight ratio 1:1), stearic acid grades 1839 and 1830 (weight ratio 3264 zxft 32225 and calcium sulfate grade 31/3724 (weight ratio 3438), calcium sulfate grade 31 and calcium sulfate grade 3724 (weight ratio 3424 zxft 3724 a and 1:1) and calcium sulfate grade 31 (weight ratio 3424 and 3624 zxft 3724 and 3624 and 31N 31).

Example 9

The present example differs from example 1 in that: the flame retardant contained only aluminum hydroxide, i.e., the magnesium hydroxide in example 1 was replaced with an equivalent amount of aluminum hydroxide.

Example 10

This example differs from example 1 in that: the flame retardant was only magnesium hydroxide, i.e., the aluminum hydroxide in example 1 was replaced with an equivalent amount of magnesium hydroxide.

Example 11

The present example differs from example 1 in that: the dispersant contained only stearic acid, i.e., the calcium stearate in example 1 was replaced with an equal amount of stearic acid.

Example 12

The present example differs from example 1 in that: the dispersant contained only calcium stearate, i.e., the stearic acid in example 1 was replaced with an equivalent amount of calcium stearate.

Example 13

This example differs from example 1 in that: the mesh number of the filling material is 100 meshes.

Example 14

This example differs from example 1 in that:

the extrusion molding involves process conditions including:

the twin screw has 6 temperature zones, the first temperature zone and the second temperature zone are 155 ℃, the sixth temperature zone is 85 ℃, and the rest temperature zones are 120 ℃. The working temperature of the single screw was 90 ℃.

In the process of double-screw extrusion, the pressure between a vacuum exhaust section and a melt pump is 1.7MPa, and the pressure of 2 vacuum pumps externally connected with the extrusion equipment is 0.08MPa.

And cooling the extruded material, wherein the current of a motor corresponding to the cooling roller is 95A, the cooling temperature of the three cooling stages is 55 ℃, 38 ℃ and 25 ℃, and the cooling time is 10s, 20s and 65s respectively.

Example 15

This example differs from example 1 in that:

the extrusion molding involves process conditions including:

the twin screw has 6 temperature zones, the temperature of the first temperature zone and the second temperature zone is 165 ℃, the temperature of the sixth temperature zone is 95 ℃, and the temperature of the rest temperature zones is 140 ℃. The working temperature of the single screw was 120 ℃.

In the process of twin-screw extrusion, the pressure between a vacuum exhaust section and a melt pump is 2.2MPa, and the pressure of 2 vacuum pumps externally connected with the extrusion equipment is 0.095MPa.

And cooling the extruded material, wherein the current of a motor corresponding to a cooling roller is 115A, the cooling temperatures of the three cooling stages are 65 ℃, 42 ℃ and 35 ℃, and the cooling time is 5s, 15s and 55s.

Example 16

The high-temperature-resistant flame-retardant material provided by the embodiment 1 is directly molded by 1 preset mold of the automobile motor cover, and the temperature of the middle part of the mold is higher than the temperature of the edges of two sides of the mold, so that the automobile motor cover is obtained.

Comparative example

Taking example 1 as an example, the following comparative examples were set up:

comparative example 1 differs from example 1 in that: the usage of the terpolymer-diene is 15 parts, the usage of the high-density polyethylene is 10 parts, the usage of the low-melt-index block copolymer polypropylene is 15 parts, and the rest conditions are unchanged.

The material obtained in comparative example 1 cannot maintain the shape of the motor cover product under the condition of treatment at 130 ℃ for 96 hours or treatment at 120 ℃ for 200 hours after being formed into the motor cover (namely the product is softened when being placed into an oven after being formed), and can be softened, flow on the surface and even be broken, while the product obtained in example 1 is not placed into the oven after being formed.

Comparative example 2 differs from example 1 in that: the usage of the terpolymer-diene is 5 parts, the usage of the high-density polyethylene is 10 parts, the usage of the low-melt-index block copolymer polypropylene is 5 parts, and the rest conditions are unchanged.

The material obtained in comparative example 2 cannot maintain the shape of the motor cover product under the condition of processing at 130 ℃ for 96h or processing at 120 ℃ for 200h after being formed into the motor cover (namely, the product is softened after being formed and then put into an oven for processing), and can be softened, flow on the surface and even be broken, but the product obtained in example 1 is not put into the oven after being formed. Comparative example 3 differs from example 1 in that: the terpolymer-diene with the trade name of 4725P is replaced by the traditional natural rubber EPDM (with the trade name of DNR 4610.01).

The material obtained in comparative example 3 cannot maintain the shape of the motor cover product under the condition of processing at 130 ℃ for 96h or processing at 120 ℃ for 200h after being formed into the motor cover (namely, the product is softened after being formed and then put into an oven for processing), and can be softened, flow on the surface and even be broken, but the product obtained in example 1 is not put into the oven after being formed.

Comparative example 4 differs from example 1 in that: the part of the flame retardant is 4.5 parts, and the flame retardant consists of aluminum hydroxide with the trade name of Space Rite S-3 and magnesium hydroxide with the trade name of Magshield S according to the weight ratio of 1.

The flame retardant effect of the product obtained in the comparison document 4 can only reach B level at the highest.

It should be emphasized that, in the present application, it is not only necessary to achieve high flame retardant performance, but also necessary to make the molded motor cover have high flame retardant performance and high temperature resistance at the same time. The flame retardant substance has the problem of damaging molecular chains, the molded product has good flame retardant effect only when the flame retardant is in a proper range, and if the flame retardant is too much, the flame retardant has the flame retardant effect, but the plastic uptake requirement cannot be met, namely the product cannot be molded, and the motor cover cannot be obtained. In addition, the structure of the polymer is irregular, and in the aspect of performance research, only a single factor cannot be seen, but multiple factors are needed to influence each other. The scheme provided by the application is that all factors are mutually adjusted to enable the overall performance of the product to tend to be stable. Therefore, it cannot be determined that the flame retardant content is high, that is, the flame retardant performance of the corresponding product is high, but whether the molded product (motor cover) can be obtained under the condition that the flame retardant content is high and whether the obtained molded product has the corresponding flame retardant effect can be considered.

Comparative example 5 differs from example 1 in that: low density polyethylene (grade PE 475) is used to replace high density polyethylene with grade 5000S.

The product obtained in comparative document 5 has a breaking strength of less than 1MPa, a right-angle tear of less than 90N/2MM (up to 50N/2 MM), and a pants-type tear strength of about 15N/2MM.

Comparative example 6 differs from example 1 in that: the temperature of the first temperature zone and the second temperature zone of the twin screw is 200 ℃.

The material could not be prepared at all under the temperature condition of comparative example 6, and the problems of wool and charring occurred during the preparation process.

Comparative example 7 differs from example 1 in that: the pressure between the vacuum exhaust section and the melt pump was 3MPa.

The material could not be prepared under the pressure condition of comparative example 7, and the problems of material blocking, motor burning loss and material carbonization occurred during the preparation process.

Comparative example 8 differs from example 1 in that: the cooling temperatures of the three cooling stages of the cooling stage are 70 ℃, 45 ℃ and 30 ℃ respectively;

the above comparative example 8 provides that temperature stress is generated in the material during the manufacturing process and annealing is insufficient.

Comparative example 9 differs from example 1 in that: the cooling temperatures of the three cooling stages of the cooling stage were 50 deg.C, 35 deg.C and 30 deg.C, respectively.

Comparative example 9 above provides a preparation process that results in too rapid an anneal and a greater thermal shrinkage of the material.

Test examples

Taking the high temperature resistant flame retardant material prepared in example 1 as an example, 5 positions in the plate material are taken to correspond to the following 001-005 measurement samples, wherein 001, 002 and 003 respectively correspond to the left, middle and right positions in the plate material, the 5 measurement samples are subjected to flame retardance (refer to GB 8410-2006), density (refer to GB/T533-2008), hardness (refer to GB/T6031-1998) and heat shrinkage (refer to GB/T7767-2009), and the 001-003 samples are subjected to performance tests in terms of fracture (refer to GB/T528-2009), right-angle tear (refer to GB/T529-2008) and pant-type tear (refer to GB/T529-2008). The results are shown in tables 1 to 3 and fig. 1 to 10.

TABLE 1 flame retardance and fracture results

Table 2 right angle tear and pant tear results

TABLE 3 Density, hardness and Heat shrinkage results

FIG. 1 is a photograph of a sample before flame retardancy test (from left to right corresponding to sample No. 001 to 005, respectively), and FIG. 2 is a photograph of a sample after the test; FIG. 3 is a photograph of a sample before fracture performance test (from left to right corresponding to sample No. 001 to 003, respectively), and FIG. 4 is a photograph of a sample after test; FIG. 5 is a photograph of the sample before the right angle tear performance test (from left to right for samples No. 001 to 003, respectively), and FIG. 6 is a photograph of the sample after the test; FIG. 7 is a photograph of a sample before the test of the pant-type tear properties (from left to right for samples No. 001 to No. 003), and FIG. 8 is a photograph of a sample after the test; FIG. 9 is a graph showing the results of hardness tests (corresponding to samples No. 001 to 005 in order from the top left to the bottom right); fig. 10 is a photograph of sample No. 001 to 005 after the heat shrinkage performance test.

In addition, the results of the high temperature resistant flame retardant materials obtained in other examples of the present application, which were tested according to the same test method, show that the materials all have better flame retardant, rupture, right angle tear, pant type tear, density, hardness and heat shrinkage effects, but all are worse than those of example 1, wherein the effects of examples 2-3 are better than those of examples 4-5.

Test example 2

The high-temperature-resistant flame-retardant material provided by the embodiment 1 is molded according to two motor cover molds in different shapes respectively to obtain corresponding automobile motor cover products which are respectively marked as a product 1 and a product 2.

The heat aging resistance, cold heat resistance, low temperature impact resistance and high temperature resistance of the above 2 products were measured in the following manners.

Wherein, the heat aging resistance is tested according to the method of JF03-1007-2010, and the specific method comprises the following steps: and (3) placing the assembly in a constant temperature box at 120 ℃ for 200h in a simulated actual loading mode, then placing the assembly at normal temperature for 1h, and inspecting the inner surface and the outer surface of the assembly. The method comprises the following steps: the visual observation shows that the phenomena of deformation, cracks, delamination, stickiness, wrinkling, chalking and the like do not occur.

The cold-heat resistance is tested according to the method of JF03-1007-2010, and specifically: the assembly simulation actual device manner was placed at-40 ℃/24h → room temperature/2 h → 90 ℃/24h → room temperature/2 h → 50 ℃ 95% RH/48h → room temperature/2 h as one cycle, three cycles were performed in total, and then the inner and outer surfaces of the assembly were inspected and the gap amount was measured. The method comprises the following steps: the appearance of the film was visually checked without deformation, cracking, delamination, stickiness, wrinkling, and powdering.

The low-temperature impact resistance is tested by referring to a method of JF07-1009-2014, and specifically comprises the following steps: placing the assembly in an actual device simulating mode in a constant temperature box at minus 40 ℃ for 24 hours, taking out the assembly, immediately and freely dropping a steel ball with the mass of 500g from the height of 500mm to impact the surface of the assembly, placing a fibrofelt with the thickness of about 10mm below the assembly, and inspecting the inner surface and the outer surface of the assembly. The method comprises the following steps: no cracking was observed visually.

The high temperature resistance is tested by referring to a method of JF03-1007-2010, and specifically comprises the following steps: and (3) placing the assembly in a thermostat at 130 ℃ for 96h in a simulated actual loading mode, then placing the assembly at normal temperature for 2h, and inspecting the inner surface and the outer surface of the assembly. The method comprises the following steps: the visual observation shows that the phenomena of deformation, cracks, delamination, stickiness, wrinkling, chalking and the like do not occur.

The results are shown in fig. 11 to 19.

Fig. 11 is a state diagram before the sample is subjected to the high temperature resistance test, and fig. 12 and 13 are state diagrams after the test. As can be seen from FIG. 13, the upper shell is acceptable, and the cracked part of the lower shell may be cracked due to extrusion deformation.

Fig. 14 is a diagram showing the sample before the cold-heat resistance test, and fig. 15 is a diagram showing the sample after the test. That is, the test specimen passed the test result in terms of cold heat resistance.

Fig. 16 is a state diagram before the sample is subjected to the low temperature impact resistance test, and fig. 17 is a state diagram after the test. That is, the test sample was qualified in terms of low temperature impact resistance.

Fig. 18 is a state diagram before the sample is subjected to the heat aging resistance test, and fig. 19 is a state diagram after the test. That is, the test sample passed the test results in terms of heat aging resistance.

The results show that: the test sample is qualified in the aspects of heat aging resistance, cold heat exchange resistance, low-temperature impact resistance and high-temperature resistance.

To sum up, the high-temperature-resistant flame-retardant material provided by the application has stronger high-temperature resistance and flame retardance, and a product prepared by the material, especially an automobile motor cover, can effectively maintain the shape of the product under the condition of 96h treatment at 130 ℃ or 200h treatment at 120 ℃, has higher ageing resistance and can reach the A0 flame-retardant standard. The preparation method of the high-temperature resistant flame-retardant material is simple and easy to operate. The corresponding preparation method of the automobile motor cover does not need foaming, only needs one mould, and can reduce waste and labor input.

The present invention has been described in terms of the preferred embodiment, and it is not intended to be limited to the embodiment. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The high-temperature-resistant flame-retardant material is characterized by being prepared by the following steps:

10 parts of terpolymer-diene with the trade name of 4725P, 6 parts of high-density polyethylene with the trade name of 5000S, 8 parts of low-melting index block copolymerization polypropylene with the trade name of K8003, 5 parts of polyethylene wax with the trade name of 100#, 14 parts of aluminum hydroxide with the trade name of Space Rite S-3 and magnesium hydroxide with the trade name of Magshield S according to the weight ratio of 5:7 as a flame retardant, 0.5 part of stearic acid with the trade name of 1830 and calcium stearate with the trade name of BS-3818 according to the weight ratio of 1:1 as a dispersing agent, 1 part of antioxidant with the trade name of 168/1010, 0.5 part of carbon black with the trade name of N219, 3 parts of silane coupling agent with the trade name of KH530, 2 parts of industrial grade white oil with the trade name of 3#, and 50 parts of 400-mesh calcium carbonate are mixed for 5min under the mechanical stirring condition of 65 KW;

extruding and molding the mixed raw materials in a mode of combining a double screw and a single screw to obtain a high-temperature-resistant flame-retardant material;

the process conditions involved in the extrusion molding include:

the twin screw has 6 temperature zones, the temperature of the first temperature zone and the second temperature zone is 160 ℃, the temperature of the sixth temperature zone is 90 ℃, and the temperature of the rest temperature zones is 125 ℃; the working temperature of the single screw is 120 ℃;

in the process of extruding the double screw, the pressure between the vacuum exhaust section and the melt pump is 2MPa, and the pressure of 2 vacuum pumps externally connected with the extruding equipment is 0.09MPa;

2. An automobile motor cover, characterized in that the automobile motor cover is made of the high temperature resistant flame retardant material as claimed in claim 1.

3. The method for manufacturing the motor cover of the automobile as claimed in claim 2, characterized by comprising the following steps: the high temperature resistant flame retardant material of claim 1 is molded into a desired shape in a mold of an automotive motor cover.

4. The method of claim 3, wherein the number of the molds is 1.

5. The method of claim 4, wherein the temperature of the mold edge is higher than the temperature of the mold center.