CN110903597A

CN110903597A - Polyether-ether-ketone composite material and preparation method and application thereof

Info

Publication number: CN110903597A
Application number: CN201911168293.3A
Authority: CN
Inventors: 赵经纬; 江圣龙; 黄志辉; 种发瑞
Original assignee: Jiujiang Tianci High & New Material Co Ltd
Current assignee: Jiujiang Tianci High & New Material Co Ltd
Priority date: 2020-02-14
Filing date: 2020-02-14
Publication date: 2020-03-24

Abstract

The invention provides a polyether-ether-ketone composite material and a preparation method thereof. The polyetheretherketone composite comprises: 90-98 parts of polyether-ether-ketone, 2-10 parts of carbon fiber, 0.5-1 part of silane coupling agent, 0.5-1 part of paraffin oil and 0.2-0.5 part of antioxidant. Compared with unmodified polyetheretherketone, the polyetheretherketone composite material provided by the invention has the advantage that the mechanical property is remarkably improved. Meanwhile, the composite material disclosed by the invention has better heat resistance and is more suitable for being used in a high-temperature environment.

Description

Polyether-ether-ketone composite material and preparation method and application thereof

Technical Field

The invention belongs to the field of high polymer materials, and particularly relates to a composite material containing polyether-ether-ketone, and a preparation method and application thereof.

Background

Polyether ether ketone (PEEK) is a linear aromatic semi-crystalline thermoplastic plastic, has the performances of high temperature resistance, solvent resistance, aging resistance, hydrolysis resistance, extremely high specific strength, specific modulus and the like, can still maintain good comprehensive performance particularly in severe environments of high temperature and high humidity, and has extremely small deformation amount during use. The excellent performance makes the polyether-ether-ketone become the most popular special engineering plastic following fluoroplastic. As a substitute for steel, aluminum, copper, titanium, Polytetrafluoroethylene (PTFE), and other high-performance materials, PEEK has been widely used in the fields of medicine (such as artificial joints), automobiles (including aviation), electronic information, transmission pipelines, daily necessities (such as electronic cigarette housings), and the like.

However, the main problems of PEEK in the practical application process are (1) poor surface cohesiveness, weak interface bonding force with the filler, poor thermal conductivity, easy thermal expansion, thermal deformation and thermal fatigue; (2) the wear resistance still can not meet the requirements of engineering, such as bracket materials, sealing rings, valves and the like; (3) the PEEK has the melting temperature of 334 ℃, high melt viscosity, high processing temperature and unstable processing technology. With the development of technologies in various fields, higher and higher requirements are put forward on the performance of materials, modification research is carried out on PEEK, and the expansion of the application range of PEEK becomes a hotspot of research in the industry. At present, the physical modification of PEEK comprises polymer blending modification, fiber reinforcement modification, whisker modification, inorganic particle filling modification, synergistic modification and the like. The fiber reinforced modification can greatly improve the friction and wear performance and mechanical performance of the material. Short carbon fibers are commonly used PEEK-modified materials. The carbon fiber modified PEEK composite material has the characteristics of small thermal expansion coefficient, high specific heat capacity, capability of storing a large amount of heat energy, low heat conductivity and the like, and simultaneously, the carbon fiber can also enhance the performances of the composite material, such as thermal shock resistance, thermal friction resistance and the like. However, the carbon fiber has smooth and inert surface and poor adhesion with the matrix, so that the pure carbon fiber modified PEEK composite material has low interface adhesion strength and is easy to generate fiber agglomeration. When the material is acted by external force, the carbon fiber is easy to be pulled out of the matrix, and the load can not be effectively transmitted through the interface. The defects seriously affect the comprehensive performance of the composite material and limit the application field of the material.

Disclosure of Invention

In view of the defects of the prior art, the main object of the present invention is to provide a carbon fiber modified polyetheretherketone composite material. The carbon fiber in the composite material is uniformly dispersed in the PEEK polymer, and the interface bonding strength is high; the mechanical properties of the composite material are significantly improved, which can be applied in a wider range of applications, including replacing traditional metals as electronic cigarette housings. In addition, compared with pure polyetheretherketone, the polyetheretherketone composite material provided by the invention has low cost and has greater competitive advantage in the market.

In order to achieve the technical effects, the invention adopts the following technical scheme:

a polyetheretherketone composite comprising:

90-98 parts of polyether-ether-ketone, 2-10 parts of carbon fiber, 0.5-1 part of silane coupling agent, 0.5-1 part of paraffin oil and 0.2-0.5 part of antioxidant.

Preferably, the polyetheretherketone composite comprises:

90-95 parts of polyether-ether-ketone, 8-10 parts of carbon fiber, 0.5-1 part of silane coupling agent, 0.5-1 part of paraffin oil and 0.2-0.5 part of antioxidant.

Preferably, the silane coupling agent and the paraffin oil are the same in parts by weight.

More preferably, the polyetheretherketone composite comprises:

90 parts of polyether-ether-ketone, 10 parts of carbon fiber, 1 part of silane coupling agent, 1 part of paraffin oil and 0.2-0.5 part of antioxidant.

As a preferred embodiment, the polyetheretherketone provided by the present invention consists of carbon fiber, polyetheretherketone, a silane coupling agent, paraffin oil and an antioxidant, the parts by weight of each component being as defined above.

Preferably, the polyetheretherketone is any of the commercially available polyetheretherketones, for example polyetheretherketone manufactured by Wedges, UK under the trade designation 450 PF.

Preferably, the carbon fibers have a length of 0.3 to 100 mm and a diameter of 6 to 7 μm.

Preferably, the silane coupling agent is selected from one or more of phenyl trimethoxy silane coupling agent, phenyl trichlorosilane coupling agent, diphenyl silane coupling agent and triphenyl chlorosilane coupling agent in any proportion.

Preferably, the antioxidant is selected from hindered phenol antioxidants; more preferably, the antioxidant is selected from one or more of antioxidant 264, antioxidant 1076, antioxidant CA and antioxidant 330 in any proportion.

The invention also aims to provide a preparation method of the polyetheretherketone composite material, which comprises the following steps:

(1) preparing the components according to the weight ratio;

(2) primary drying

Drying the polyether-ether-ketone;

(3) carbon fiber pretreatment

Diluting a silane coupling agent with paraffin oil, and then fully mixing the silane coupling agent with carbon fiber to obtain pretreated carbon fiber;

(4) high speed mixing

Uniformly mixing the dried polyether-ether-ketone obtained in the step (2), the pretreated carbon fiber obtained in the step (3) and an antioxidant in a high-speed mixing device to obtain a mixed material;

(5) extrusion granulation

Extruding and granulating the mixed material obtained in the step (4) by using a double-screw mixing extruder to obtain a granular material;

(6) secondary drying

And (5) drying the granular material obtained in the step (5) to obtain the granular material.

Preferably, the drying temperature of the step (2) and the step (6) is 100 ℃ and 150 ℃, and the drying time is 2-8 hours.

More preferably, the step (2) and the step (6) are carried out in a vacuum drying oven at a drying temperature of 100 ℃ and 150 ℃ for a drying time of 2-8 hours.

Preferably, in the step (5), the granular material is cylindrical granular material with the length of 2-6 mm.

The invention also aims to provide application of the polyether-ether-ketone composite material or the polyether-ether-ketone prepared by the preparation method in preparing parts which work in a high-temperature environment for a long time.

Preferably, the component operating in a high temperature environment for a long period of time includes, but is not limited to, an electronic cigarette accessory, in particular an electronic cigarette housing.

Preferably, the application refers to injection molding the polyetheretherketone composite in an injection molding apparatus.

Preferably, the process conditions of the injection molding are as follows: the injection temperature of the injection molding machine is 360-400 ℃, the injection pressure is 40-150MPa, the mold closing pressure is 20-80MPa, and the mold temperature is 150-200 ℃.

According to the polyether-ether-ketone composite material provided by the invention, the carbon fibers are uniformly dispersed in the polyether-ether-ketone resin, the interfacial bonding force with a polymer is high, and the agglomeration phenomenon is avoided. As can be seen from the SEM morphology picture of the brittle fracture surface of the polyether-ether-ketone composite material, the carbon fibers are not agglomerated and are basically vertical to the brittle fracture surface (see figure 1 in particular). Such an orientation of the carbon fibres is also advantageous for increasing the mechanical strength of the composite material. In addition, the composite material provided by the invention has the characteristics of small thermal expansion coefficient, high specific heat capacity, low thermal conductivity and the like, and can store a large amount of heat energy; compared with unmodified polyether ether ketone resin, the composite material disclosed by the invention is better in heat resistance, and is particularly suitable for application scenes such as electronic cigarette shells and the like which need to be in a heating state frequently.

In addition, the addition of the carbon fiber in the polyether-ether-ketone composite material provided by the invention can reach 10%, and the dosage of polyether-ether-ketone is correspondingly reduced, so that the cost of the composite material is reduced.

Drawings

The present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a Scanning Electron Microscope (SEM) photograph of brittle sections of polyetheretherketone composites prepared in examples 1-5 and comparative examples 1-2. Wherein (a): comparative example 1, (b): example 1, (c): example 2, (d): example 3, (e): example 4, (f): example 5, (g): comparative example 2.

FIG. 2 is a Scanning Electron Microscope (SEM) photograph of a brittle section of the polyetheretherketone composite prepared in example 5. Wherein (a) and (b) are SEM photographs of different cross sections.

FIG. 3 is a Scanning Electron Microscope (SEM) photograph of a brittle section of the polyetheretherketone composite prepared in comparative example 2.

FIG. 4 is a bar graph showing the results of measuring the tensile strength of the composite polyetheretherketone specimens obtained in examples 1 to 8 and comparative examples 1 to 2.

Detailed Description

The technical solutions in the embodiments of the present invention will be further described below with reference to the embodiments of the present invention. It is apparent that the following examples are merely illustrative and are not intended to limit the scope of the present invention. Based on the spirit of the present disclosure, the embodiment of the present invention is obviously changed and adjusted by those skilled in the art, and all the embodiments are within the scope of the present invention.

Unless otherwise specified, raw materials, reagents, equipments, apparatuses and the like used in the following examples were purchased from commercial sources, and the methods used were those conventional in the art. Wherein:

polyether ether ketone: england Weggess 450PF

Carbon fiber: LXTD, a manufacturer of Shandong Lu fiber building materials science and technology Co., Ltd

Phenyl trimethoxysilane silane coupling agent: trade name Z-6124, Qufuchenguang chemical Co., Ltd

Phenyl trichlorosilane coupling agent: number KA-103, Japan shin-Etsu Co

Diphenyl silane coupling agent: KH560, Hengzhou Hengda chemical products Co., Ltd

Triphenylchlorosilane coupling agent: KH570, Hengzhou Hengda chemical products Co., Ltd

Paraffin oil: 500, Hengshui Diyi petrochemical Co Ltd

Antioxidant: 1076 Angel synthetic chemical Co., Ltd, Yixing City

EXAMPLES 1 to 5A polyetheretherketone composite

The raw materials of the polyetheretherketone composites of examples 1-5 are shown in table 1; the preparation method comprises the following steps:

(1) preparing raw materials according to the mixture ratio shown in table 1; wherein, the silane coupling agents adopt phenyltrimethoxysilane silane coupling agents KA-103, and the antioxidants adopt 1010;

(2) primary drying: and drying the PEEK powder for 4 hours in a vacuum drying oven at 100 ℃ to obtain the dried PEEK.

(3) Pretreating carbon fibers: diluting the silane coupling agent with paraffin oil with the same volume, and then fully mixing the silane coupling agent with the carbon fibers to ensure that the silane coupling agent is uniformly distributed on the surfaces of the carbon fibers to obtain the pretreated carbon fibers.

(4) High-speed mixing: and (3) placing the dried polyether-ether-ketone obtained in the step (2), the pretreated carbon fiber obtained in the step (3) and the antioxidant into a high-speed mixer for uniformly mixing to obtain a uniformly mixed material.

(5) And (3) extruding and granulating: transferring the uniformly mixed material obtained in the step (4) to a double-screw compounding extruder, wherein the parameter setting of the extruder is based on the PEEK extruding parameter setting of the actual extruder; and cooling the extruded strips to normal temperature, and then cutting into granules, wherein the cut granules are cylindrical granular materials with the length of 2-6 mm.

(6) Secondary drying: and (4) drying the cut granular materials obtained in the step (5) in a vacuum drying oven at 100 ℃ for 4 hours to obtain dried granular materials.

(7) Injection molding: for the convenience of performance measurement, the granular materials after the secondary drying treatment of each example were prepared into ASTM D638 type IV dumbbell specimens by a conventional injection molding method; wherein the injection molding temperature of the injection molding machine is 390 ℃, the injection molding pressure is 80MPa, the mold closing pressure is 50MPa, and the mold temperature is 200 ℃.

TABLE 1 composition of polyetheretherketone for examples 1-5

Examples	PEEK(kg)	Carbon fiber (kg)	Silane coupling agent (kg)	Paraffin oil	Antioxidant (kg)
						1	98	2	1	1	0.4
2	96	4	1	1	0.4
						3	94	6	1	1	0.4
4	92	8	1	1	0.4
						5	90	10	1	1	0.4

Example 6A polyetheretherketone composite

The polyetheretherketone composite material of the embodiment comprises the following raw materials:

6 parts of carbon fiber, 94kg of polyether-ether-ketone, 1kg of phenyl trichlorosilane coupling agent, 1kg of paraffin oil and 0.4kg of antioxidant, wherein 1 part =1 kg.

Prepared essentially as in example 1, except that: the carbon fibers are pretreated with a phenyltrichlorosilane coupling agent.

Example 7A polyetheretherketone composite

6 parts of carbon fiber, 94kg of polyether-ether-ketone, 1kg of diphenyl silane coupling agent, 1kg of paraffin oil and 0.4kg of antioxidant, wherein 1 part =1 kg.

Prepared essentially as in example 1, except that: the carbon fibers are pretreated with a diphenylsilane coupling agent.

Example 8A polyetheretherketone composite

6 parts of carbon fiber, 94kg of polyether-ether-ketone, 1kg of triphenylchlorosilane coupling agent, 1kg of paraffin oil and 0.4kg of antioxidant, wherein 1 part =1 kg.

Prepared essentially as in example 1, except that: the carbon fiber is pretreated by a triphenylchlorosilane coupling agent.

Comparative example 1 a polyetheretherketone composite

The polyether-ether-ketone composite material of the comparative example comprises the following raw materials:

0 part of carbon fiber, 100 parts of polyether-ether-ketone, 1 part of phenyl trimethoxy silane coupling agent, 1 part of paraffin oil and 0.4 part of antioxidant; wherein 1 part =1 kg.

Prepared essentially as in example 1, except that: the carbon fiber pretreatment step is not needed, and the dried polyetheretherketone, the phenyltrimethoxysilane coupling agent, the paraffin oil and the antioxidant are uniformly mixed in a high-speed mixer.

Comparative example 2 a polyetheretherketone composite

6 parts of carbon fiber, 94 parts of polyether-ether-ketone, 0 part of silane coupling agent, 0 part of paraffin oil and 0 part of antioxidant; wherein 1 part =1 kg.

Prepared essentially as in example 1, except that: the carbon fiber pretreatment step is not needed, and the dried polyether-ether-ketone and the carbon fiber are uniformly mixed in a high-speed mixer.

Comparative example 3 a polyetheretherketone composite

12 parts of carbon fiber, 88 parts of polyether-ether-ketone, 1 part of phenyl trimethoxy silane coupling agent, 1 part of paraffin oil and 0.4 part of antioxidant; wherein 1 part =1 kg.

Prepared according to the same method as example 1; as a result, difficulty in extrusion occurs in "extrusion pelletization", so that the screw is damaged.

Test example 1 determination of Properties of polyether Ether ketone composite materials of examples and comparative examples

1. SEM (scanning Electron microscope) morphology picture of brittle section

Samples of the polyetheretherketone composite material prepared in examples 1-5 and comparative examples 1-2 were taken and brittle-broken by liquid nitrogen freezing. SEM photographs of brittle fracture lines of respective samples were taken, and the obtained photographs are shown in FIG. 1, in which (a) is a brittle fracture SEM photograph of the sample of comparative example 1, (b) to (f) are brittle fracture SEM photographs of the samples of examples 1 to 5, respectively, and (g) is a brittle fracture SEM photograph of the sample of comparative example 2.

In the above FIG. 1, (b) to (f) show that the carbon fibers are uniformly dispersed in the matrix without aggregation, as compared with (a); and the carbon fiber and the polyetheretherketone are tightly combined, and no pore exists between the two materials. In addition, it can be seen from the figure that the carbon fibres are substantially perpendicular to the brittle fracture, i.e. the carbon fibres are strongly oriented within the matrix. (g) The circles in (a) show the presence of voids between the carbon fibers and the matrix, indicating that the adhesion of the carbon fibers to the polyetheretherketone is weak in the absence of the silane coupling agent. In the preparation process of the composite material, the melt, the screw and the inner wall of the charging barrel generate huge shearing force through the mixing and shearing action of the double screws, although the composite material can shear long fibers into shorter fibers and can uniformly mix the carbon fibers which are agglomerated together; however, this force also causes the carbon fibers that are not tightly bonded to the peek matrix to pull out of the matrix.

Bonding of carbon fibers to a polyetheretherketone matrix

Samples of the peek composite materials prepared in example 5 and comparative example 2 were taken and observed under a Scanning Electron Microscope (SEM) and photographed, respectively, in fig. 2 and 3.

SEM photographs of different sections shown in FIG. 2 show that the carbon fibers in the PEEK composite material are embedded in the PEEK matrix and are coated by the matrix, and the interface between the carbon fibers and the matrix is well combined. This facilitates the transfer of load from the matrix to the reinforcement carbon fibers, thereby increasing the tensile strength and tensile modulus of the material. While the carbon fiber of comparative example 2, which was not pretreated with a coupling agent, was added to PEEK, the carbon fiber could not be tightly bonded to the matrix even though it was mixed and sheared by twin screws, and it can be seen from fig. 3 that a certain void existed between the carbon fiber and the matrix, as indicated by the circles in the figure.

Mechanical property of polyether-ether-ketone composite material

The tensile strength of the composite polyetheretherketone specimens obtained in examples 1 to 8 and comparative examples 1 to 2 was measured according to the method described in ASTM D638, and the results are shown in FIG. 4. The tensile strength of the sample of comparative example was not determined due to the failed preparation of the composite polyetheretherketone of comparative example 3.

As can be seen from fig. 4:

(1) the carbon fiber can improve the mechanical property of the polyether-ether-ketone. Whether the carbon fiber is pretreated or not, the tensile strength of the polyetheretherketone composite material containing the carbon fiber is greater than that of pure polyetheretherketone.

(2) For the polyetheretherketone composite of the present invention, the tensile strength of the composite increased with increasing carbon fiber content in a certain range, especially in examples 4 and 5 with carbon fiber content of 8% and 10%, the tensile strength increased dramatically, significantly more than in the other examples. Examples 4 and 5 are preferred embodiments of the present invention. However, if the amount of the carbon fiber is more than 10 parts (i.e., the composite material of comparative example 3), the mechanical properties of the composite material are hardly increased further. Meanwhile, the inventor finds that the composite material is difficult to extrude and easy to damage a screw, and has high fluidity and high viscosity in a molten state, and is difficult to injection mold and process, so that the composite material cannot be practically applied.

(2) Comparative example 2, in which the carbon fiber was not pretreated with the silane coupling agent, had a tensile strength smaller than that of example 3, in which the amount of the carbon fiber was the same, and substantially equivalent to that of example 2, in which the amount of the carbon fiber was 4%. The reason for this is that the reinforcing effect of the carbon fibers cannot be sufficiently exhibited because the carbon fibers have poor adhesion to the polyetheretherketone matrix.

(3) Examples 6-8 used different silane coupling agents, but compared to example 3, which used the same amount of carbon fiber, there was no significant difference in mechanical properties between the composites. The different silane coupling agents can achieve better effect on the pretreatment of the carbon fiber, and the effect is equivalent.

4. Heat resistance of polyether-ether-ketone composite material

DSC and TG analysis of the composite material can find that: as the carbon fiber content increases, the initial decomposition temperature increases. This phenomenon can be explained by the fact that the shielding effect of the carbon fibers hinders the decomposition of the polymer to some extent. Because the thermal conductivity of the carbon fiber is higher than that of the PEEK matrix, heat can be effectively transmitted and absorbed through the carbon fiber, and thus the thermal stability of the composite material is increased along with the increase of the content of the carbon fiber. The maximum decomposition temperature of the polyether-ether-ketone composite material also increases along with the increase of the content of the carbon fiber, and the result further shows that the polyether-ether-ketone composite material can improve the thermal stability of the polyether-ether-ketone composite material. The composite specific thermal decomposition test data is summarized in table 2.

Table 2 results of thermal property test of peek composite materials of comparative example 1 and examples 1 to 5

In summary, the present invention provides a carbon fiber polyetheretherketone composite. The carbon fiber in the composite material has strong adhesive force with the polyether-ether-ketone; compared with unmodified polyetheretherketone, the mechanical property of the composite material is obviously improved. Meanwhile, the composite material disclosed by the invention has better heat resistance and is more suitable for being used in a high-temperature environment. With the addition of the carbon fiber, the consumption of the polyetheretherketone is reduced, the cost of the composite material is reduced, and the problems of high cost and high price of the polyetheretherketone product are solved to a certain extent, so that the polyetheretherketone composite material can be more widely applied to the fields of automobiles, aerospace, processing and manufacturing and the like, and is particularly suitable for being used as a material of electronic cigarette heating accessories (such as a shell).

Therefore, the scope of the present invention should not be limited to the disclosure of the embodiments, but includes various alternatives and modifications without departing from the scope of the present invention, which is defined by the claims of the present patent application.

Claims

1. A polyetheretherketone composite comprising:

2. The polyetheretherketone composite of claim 1, wherein the polyetheretherketone composite comprises:

3. The polyetheretherketone composite of claim 1 or 2, wherein the silane coupling agent and the paraffinic oil are in the same parts by weight.

4. The polyetheretherketone composite of claim 3, wherein the polyetheretherketone composite comprises:

5. A polyetheretherketone composite material consisting of carbon fibres, polyetheretherketone, a silane coupling agent, paraffin oil and an antioxidant, the parts by weight of the components being as defined in any one of claims 1 to 4.

6. The polyetheretherketone of any of claims 1 to 5, wherein the polyetheretherketone is any of commercially available polyetheretherketone;

preferably, the carbon fiber has a length of 0.3-100 mm and a diameter of 6-7 μm;

preferably, the silane coupling agent is selected from one or more of phenyl trimethoxy silane coupling agent, phenyl trichlorosilane coupling agent, diphenyl silane coupling agent and triphenyl chlorosilane coupling agent in any proportion;

7. A method of preparing a polyetheretherketone composite according to any one of claims 1 to 6, comprising:

(1) preparing the components according to the weight ratio;

(2) primary drying

Drying the polyether-ether-ketone;

(3) carbon fiber pretreatment

(4) high speed mixing

(5) extrusion granulation

(6) secondary drying

8. The method according to claim 7, wherein the drying temperature of the steps (2) and (6) is 100 ℃ and 150 ℃, and the drying time is 2-8 hours;

more preferably, the step (2) and the step (6) are carried out in a vacuum drying oven, the drying temperature is 100 ℃ and 150 ℃, and the drying time is 2-8 hours;

9. Use of a polyetheretherketone composite material according to any one of claims 1 to 6 or polyetheretherketone prepared by the method of preparation according to claim 7 or 8 for the preparation of a component operating in a high temperature environment for a long period of time.

10. Use according to claim 9, wherein said components that operate in a high temperature environment for long periods of time include, but are not limited to, electronic cigarette accessories, in particular electronic cigarette housings;

preferably, the application refers to injection molding the polyetheretherketone composite in an injection molding apparatus;