CN111019341A - Toughened conductive flame-retardant polyamide 6 composite material and preparation method thereof - Google Patents
Toughened conductive flame-retardant polyamide 6 composite material and preparation method thereof Download PDFInfo
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- CN111019341A CN111019341A CN201911393632.8A CN201911393632A CN111019341A CN 111019341 A CN111019341 A CN 111019341A CN 201911393632 A CN201911393632 A CN 201911393632A CN 111019341 A CN111019341 A CN 111019341A
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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
- C08L77/00—Compositions of polyamides obtained by reactions forming a carboxylic amide link in the main chain; Compositions of derivatives of such polymers
- C08L77/02—Polyamides derived from omega-amino carboxylic acids or from lactams thereof
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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
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/02—Elements
- C08K2003/026—Phosphorus
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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
- C08K2201/00—Specific properties of additives
- C08K2201/001—Conductive additives
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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
- C08L2201/00—Properties
- C08L2201/02—Flame or fire retardant/resistant
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Abstract
The invention discloses a toughened conductive flame-retardant polyamide 6(PA6) composite material and a preparation method thereof, belonging to the technical field of modification of high polymer materials. The toughened conductive flame-retardant polyamide 6 composite material is prepared from the following components in parts by weight: PA 6: 50-60 parts; conductive carbon black: 10-20 parts; carbon Nanotube (CNT): 1-10 parts; a toughening agent: 5-10 parts; antioxidant: 5-10 parts; 10-20 parts of a flame retardant. The invention adopts the conductive carbon black and CNT composite filling to improve the conductivity of the PA6 material, improves the flame retardant property of the PA6 material through the flame retardant, and simultaneously toughens the PA6 through the toughening agent to keep the toughness of the PA6 material, thereby obtaining the flame retardant polyamide 6 composite material with high conductivity and high toughness, and being particularly suitable for being applied to the fields of industrial machinery, automobile parts, engineering structural members and the like.
Description
Technical Field
The invention relates to the field of modification of high polymer materials, in particular to a toughened, conductive and flame-retardant polyamide 6 composite material and a preparation method thereof.
Background
PA6, also known as Nylon 6, is a translucent or opaque opalescent crystalline polymer, also known under the chemical name polycaprolactam, and is one of the most commonly used engineering plastics.
The polyamide 6 has higher tensile strength and compressive strength and excellent chemical resistance, and the performance of the polyamide can be further improved by means of reinforcement, toughening and the like, so that the application range of the polyamide is widened.
Based on the continuous development of the automobile industry, the polyamide 6 material with excellent conductivity and good flame retardance has wide application prospect. However, in order to meet the performance requirements, a higher content of conductive filler and flame retardant is often required to be added, so that the mechanical properties, especially the impact resistance, of the material are greatly reduced, and the application of the conductive flame-retardant polyamide 6 is greatly limited.
Therefore, how to provide a toughened conductive flame-retardant polyamide 6 composite material and a preparation method thereof are problems to be solved by those skilled in the art.
Disclosure of Invention
In view of the above, the present invention aims to provide a toughened conductive flame-retardant polyamide 6 composite material and a preparation method thereof. By selecting a proper toughening agent and adjusting the optimal ratio of the flame retardant to the conductive filler, excellent electrical property and flame retardant property of the polyamide 6 material are successfully obtained, and sufficient toughness of the material is ensured, so that the conductive flame retardant polyamide 6 composite material with higher toughness is obtained, and the application range of the material is widened.
In order to achieve the purpose, the invention adopts the following technical scheme:
the toughened conductive flame-retardant polyamide 6 composite material comprises the following components in parts by weight: PA 6: 50-60 parts of conductive carbon black: 10-20 parts of CNT: 1-10 parts of a toughening agent: 5-10 parts of antioxidant: 5-10 parts of flame retardant and 10-20 parts of flame retardant.
Further, the reinforced and toughened conductive flame-retardant polyamide 6 composite material comprises the following components in parts by weight: PA 6: 51-59 parts of conductive carbon black: 10.5-19.5 parts of CNT: 2-9 parts of a toughening agent: 5.5-9.5 parts of antioxidant: 0.5-5.5 parts of flame retardant and 11-19 parts of flame retardant.
Further, the reinforced and toughened conductive flame-retardant polyamide 6 composite material comprises the following components in parts by weight:
by adopting the technical scheme, the technical effects are as follows: the toughened conductive flame-retardant polyamide material has excellent mechanical property, strong impact resistance, flame retardance and good electrical property.
Further, the PA6 is PA6 with a viscosity value of 2.2-2.5.
By adopting the technical scheme, the technical effects are as follows: if the viscosity is less than 2.2, the impact resistance of the composite material is low; if the viscosity is higher than 2.5, poor dispersion of the filler may result, the desired properties may not be achieved and the stability may be poor. And 2.2-2.5 of PA6 can not only fully disperse the filler, but also make the composite material have certain toughness.
Further, the conductive carbon black is carbon black having a resistivity of less than 10^3 Ω.
By adopting the technical scheme, the technical effects are as follows: the carbon black with lower resistivity is selected, so that the filling fraction is less, the excellent electrical property is achieved, and if the resistivity is too high, the filling fraction is increased, and the mechanical property of the material is reduced.
Further, the CNTs are single-walled carbon nanotubes or multi-walled carbon nanotubes.
By adopting the technical scheme, the technical effects are as follows: the carbon nano tube can reduce the resistance of the material and improve the conductivity, and simultaneously has synergistic effect with the carbon black, so that the adding proportion of the carbon black is reduced, and the loss of the mechanical property of the material is avoided.
Further, the toughening agent is POE grafted MAH.
By adopting the technical scheme, the technical effects are as follows: the POE grafted MAH can effectively combine the elastomer with the matrix resin and improve the impact strength of the composite material.
Further, the antioxidant is one or more of antioxidant 1010, antioxidant 168, antioxidant 1098 and antioxidant 608.
By adopting the technical scheme, the technical effects are as follows: the addition of an antioxidant can avoid degradation during processing.
Further, the flame retardant is red phosphorus flame-retardant master batch.
By adopting the technical scheme, the technical effects are as follows: the red phosphorus flame-retardant master batch can promote the charring effect in the combustion process, and has the flame-retardant effect.
On the other hand, the invention further provides a preparation method of the toughened conductive flame-retardant polyamide 6 composite material, which comprises the following steps:
s1, weighing the raw materials according to the proportion of the toughened conductive flame-retardant polyamide 6 composite material as claimed in any one of claims 1 to 8, and drying;
s2, adding the dried raw materials into a high-speed mixer for mixing, and extruding and granulating through an extruder under the conditions that the rotating speed is 240 plus 300rpm and the temperature of each zone is 180 plus 260 ℃ to obtain the toughened conductive flame-retardant polyamide 6 composite material.
Further, in step S1, the mixing temperature is 70 to 90 ℃, preferably 80 ℃.
Further, in step S1, the rotation speed of the mixing is 300-800 rpm.
Further, in step S2, the rotation speed of the mixing is 280 rpm.
Further, the temperature of each zone of the extruder comprises 180-200 ℃ of the first zone, 240-250 ℃ of the second zone, 240-250 ℃ of the third zone, 240-250 ℃ of the fourth zone, 240-250 ℃ of the fifth zone, 230-240 ℃ of the sixth zone, 230-240 ℃ of the seventh zone, 230-240 ℃ of the eighth zone, 230-240 ℃ of the ninth zone and 240-250 ℃ of the head.
According to the technical scheme, compared with the prior art, the toughened conductive flame-retardant polyamide 6 composite material and the preparation method thereof have the following technical effects:
the toughened conductive flame-retardant polyamide PA6 material provided by the invention is filled with the conductive carbon black and the carbon nano tubes in a composite manner, so that the material is endowed with excellent electrical properties on the premise of ensuring the mechanical properties of the material.
(1) The POE grafted MAH adopted by the invention ensures the full combination of the elastomer and the matrix resin and improves the impact property of the composite material; the red phosphorus flame-retardant master batch promotes the carbon forming effect in the combustion process, is convenient to process and disperse, and provides a better flame-retardant effect.
(2) The preparation method of the toughened conductive flame-retardant polyamide PA6 material provided by the invention has the advantages of excellent performance and wide processing window, and is suitable for application with higher requirements on flame retardance and electrical performance of the material.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all 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.
According to the toughened conductive flame-retardant polyamide PA6 material provided by the embodiment of the invention, the conductive performance of the material is enhanced by introducing the conductive carbon black and the carbon nano tubes; the impact resistance of the material is improved by introducing the toughener POE to graft MAH; by introducing the antioxidant, the decomposition condition of the material in the processing process is improved; the flame retardant performance of the material is realized by introducing the red phosphorus flame retardant master batch. On the other hand, the preparation method of the toughened conductive flame-retardant polyamide PA6 composite material provided by the embodiment of the invention is characterized in that PA6, conductive carbon black, CNT, an antioxidant, POE grafted MAH and red phosphorus flame-retardant master batches are added into a high-speed mixer in proportion and mixed uniformly, the extrusion process is optimized, the material is ensured to be dispersed fully, and the preparation method is suitable for the field with higher requirements on the conductivity and the flame retardant property of the material.
In addition, the raw materials used in the comparative examples and examples: polyamide PA6-1: relative viscosity 2.4 (sulfuric acid process), polyamide PA6-2: relative viscosity 2.7 (sulfuric acid process), polyamide PA 6-3: relative viscosity 3.2 (sulfuric acid method), conductive carbon black: carbon black having a resistivity of less than 10^3 Ω; carbon nanotube: the diameter is 10-15 nm, and the toughening agent is 1: EPDM grafted MAH, toughener 2: POE grafted MAH, antioxidant: antioxidant 1010/168/1098/608, flame retardant 1: melamine cyanurate MCA, flame retardant 2: a red phosphorus flame retardant.
The product performance testing method comprises the following steps: mechanical properties: conductivity properties as evaluated according to ISO method: testing the surface resistance according to IEC60093, and testing the flame retardant property: flow properties according to UL94 test: the melt index was measured according to ISO 1133.
Comparative examples 1 to 3
Mixing the dried PA6 resin, conductive carbon black, carbon nano tubes, an antioxidant, a flame retardant and a toughening agent according to the proportion in Table 1, continuously and uniformly adding the mixture into a main machine cylinder of a double-screw extruder with a screw diameter of 35mm and a length-diameter ratio of L/D (L/D) of 36 by using a double-screw feeder, controlling the temperature of each section of the main machine cylinder in a segmented manner, sequentially controlling the temperature from a feed inlet to a machine head outlet at 180 ℃, 250 ℃, 245 ℃ and 250 ℃ and controlling the rotating speed of double screws at 280 revolutions per minute, cooling extruded strips by a water tank, and then pelletizing to obtain the PA6 modified particles. The prepared pellets were dried in a forced air oven at 120 ℃ for 4 hours, injection molded into standard sample bars with a plastic injection molding machine at 250 ℃ and the injection molded bars were immediately placed in a glass desiccator and subjected to a performance test after standing at room temperature for at least 24 hours. The test results are shown in Table 1
TABLE 1 compositions and Properties of comparative examples 1-3
As can be seen from the test results in table 1, polyamide composites were prepared with different PA6 resins. Impact properties are similar, the material prepared from PA6-1 has higher flowability than other resins, and is convenient to process, but the conductivity, flame retardant property and impact resistance of the material are greatly improved according to the old space.
Examples 1 to 3
Using the same processing techniques as in comparative examples 1-3 and selecting the formulation system with slightly better flow property in the above experiment as the basic formulation, the materials were prepared according to the ratios in Table 2, and the results of the property tests are shown in Table 2
TABLE 2 compositions and Properties of examples 1-3
The test results of the above embodiments show that the electrical property of the material can be significantly improved by increasing the content of the conductive filler, the impact property and the fluidity are slightly reduced, and the performance of the selected toughening agent 2 is superior to that of the toughening agent 1. The action mechanism is that the conductive filler is added, so that a conductive path is conveniently formed in the material, and the resistance is reduced. There is still room for improvement in the flame retardant properties of the material of this example.
Examples 4 to 5
The processing technology of comparative examples 1-3 is adopted, a formula system with slightly better performance in the previous examples is selected as a basic formula, the content of each component is adjusted, the materials are prepared according to the mixture ratio of table 3, and the performance test results are shown in table 3
TABLE 3 compositions and Properties of examples 4-5
From the test results of the above examples, it can be seen that flame retardant 2 performs better than flame retardant 1. The flame retardant content is increased, so that the material can reach the UL 94V 0 grade on the premise of having excellent conductivity and impact strength, and meanwhile, the fluidity can meet the molding processing requirements of different parts.
In summary, the toughened conductive flame-retardant polyamide 6 composite material provided by the embodiment of the invention is prepared by selecting the appropriate toughening agent, the conductive filler and the flame retardant, optimizing the proportion and improving the processing technology, so that the contradiction among the conductive performance, the flame retardant performance and the impact strength of the toughened polyamide 6 material is greatly improved, and the polyamide 6 composite material with high impact strength, excellent conductive performance and flame retardant performance is prepared.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (9)
1. The toughened conductive flame-retardant polyamide 6 composite material is characterized by comprising the following components in parts by weight: PA 6: 50-60 parts of conductive carbon black: 10-20 parts of CNT: 1-10 parts of a toughening agent: 5-10 parts of antioxidant: 5-10 parts of flame retardant and 10-20 parts of flame retardant.
2. The toughened conductive flame-retardant polyamide 6 composite material as claimed in claim 1, which is characterized by comprising the following components in parts by weight: PA 6: 51-59 parts of conductive carbon black: 10.5-19.5 parts of CNT: 2-9 parts of a toughening agent: 5.5-9.5 parts of antioxidant: 0.5-5.5 parts of flame retardant and 11-19 parts of flame retardant.
3. The toughened electrically conductive flame retardant polyamide 6 composite material according to claim 1 or 2, characterized in that the PA6 is PA6 with a viscosity of 2.2 to 2.5.
4. The toughened electrically conductive flame retardant polyamide 6 composite material according to claim 1 or 2, characterized in that the electrically conductive carbon black is carbon black having a resistivity of less than 10^3 Ω. cm.
5. The toughened conductive flame retardant polyamide 6 composite material as claimed in claim 1 or 2, wherein said CNTs are single-walled carbon nanotubes or multi-walled carbon nanotubes.
6. The toughened conductive flame retardant polyamide 6 composite material as claimed in claim 1 or 2, wherein the toughening agent is POE grafted MAH.
7. The toughened conductive flame retardant polyamide 6 composite material as claimed in claim 1 or 2, wherein the antioxidant is a mixture of one or more of antioxidant 1010, antioxidant 168, antioxidant 1098 and antioxidant 608.
8. The toughened conductive flame-retardant polyamide 6 composite material as claimed in claim 1 or 2, wherein the flame retardant is red phosphorus flame-retardant master batch.
9. The preparation method of the toughened conductive flame-retardant polyamide 6 composite material as claimed in claims 1 to 8, characterized by comprising the following preparation steps:
1) weighing the raw materials according to the mixture ratio of claim 1;
2) adding the dried raw materials into a high-speed mixer for mixing, continuously and uniformly adding the mixed materials into a main machine cylinder of a double-screw extruder with a screw diameter of 35mm and a length-diameter ratio L/D of 36 by using a double-screw feeder, wherein the temperature of each section of the main machine cylinder is controlled in a segmented manner, and the temperature of the main machine cylinder from a feed inlet to a machine head outlet is 180-200 ℃ in a first zone, 240-250 ℃ in a second zone, 240-250 ℃ in a third zone, 240-250 ℃ in a fourth zone, 240-250 ℃ in a fifth zone, 230-240 ℃ in a sixth zone, 230-240 ℃ in a seventh zone, 230-240 ℃ in an eighth zone, 230-240 ℃ in a ninth zone and 240-250 ℃ in a head. The rotating speed of the double screw is 280 revolutions per minute, and the extruded material strips are cooled by a water tank and then cut into granules to obtain the toughened conductive flame-retardant polyamide 6 composite material.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101081929A (en) * | 2007-06-08 | 2007-12-05 | 深圳市科聚新材料有限公司 | Composite material easy for coating thermoplastic elastomer and preparation method thereof |
| CN102558839A (en) * | 2011-12-21 | 2012-07-11 | 上海普利特复合材料股份有限公司 | Low odor, anti-static electricity, red phosphorus flame retardant thermoplastic composition and preparation method thereof |
| CN102863783A (en) * | 2012-10-15 | 2013-01-09 | 合肥利美科技有限公司 | High-toughness electric conduction nylon composite material and preparation method thereof |
| CN103382302A (en) * | 2013-07-02 | 2013-11-06 | 浙江俊尔新材料股份有限公司 | Red phosphorus flame-retardant nylon composition and preparation method thereof |
| CN108034231A (en) * | 2017-11-24 | 2018-05-15 | 广东威林工程塑料股份有限公司 | A kind of outdoor used in air exchange fan high-low temperature resistant high-dimensional stability and the PA composite materials of anti-UV agings and preparation method thereof |
-
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- 2019-12-31 CN CN201911393632.8A patent/CN111019341A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101081929A (en) * | 2007-06-08 | 2007-12-05 | 深圳市科聚新材料有限公司 | Composite material easy for coating thermoplastic elastomer and preparation method thereof |
| CN102558839A (en) * | 2011-12-21 | 2012-07-11 | 上海普利特复合材料股份有限公司 | Low odor, anti-static electricity, red phosphorus flame retardant thermoplastic composition and preparation method thereof |
| CN102863783A (en) * | 2012-10-15 | 2013-01-09 | 合肥利美科技有限公司 | High-toughness electric conduction nylon composite material and preparation method thereof |
| CN103382302A (en) * | 2013-07-02 | 2013-11-06 | 浙江俊尔新材料股份有限公司 | Red phosphorus flame-retardant nylon composition and preparation method thereof |
| CN108034231A (en) * | 2017-11-24 | 2018-05-15 | 广东威林工程塑料股份有限公司 | A kind of outdoor used in air exchange fan high-low temperature resistant high-dimensional stability and the PA composite materials of anti-UV agings and preparation method thereof |
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