CN103965389B - The gas-phase polymerization production method of CNT-polymer composite and device - Google Patents

Abstract

The invention discloses a gas-phase polymerization production method of a carbon nanotube-polymer composite material, comprising: providing a catalyst and a carbon nanotube; providing a polymerized monomer; polymerizing the monomer, the catalyst and the carbon nanotube in an anhydrous and oxygen-free environment Carrying out gas phase polymerization to obtain carbon nanotube-polymer composites in situ. Carbon nanotubes are one-dimensional nano-carbon materials with high strength and good electrical and thermal conductivity. In situ carbon nanotube-polymer composites obtained by gas-phase polymerization through this method, carbon nanotubes can replace carbon black to prevent the polymer from melting and bonding due to exothermic reaction, and make the composite material have good properties. Strength and electrical and thermal conductivity. The method is especially suitable for gas phase polymerization to produce low softening temperature polymer material (such as ethylene propylene rubber, etc.) compound. The invention also discloses a gas phase polymerization production device of carbon nanotube-polymer composite material.

Description

Gas-phase polymerization production method and device of carbon nanotube-polymer composite material

technical field

The invention relates to the field of basic chemical industry, in particular to a gas-phase polymerization production method and device of a carbon nanotube-polymer composite material.

Background technique

Ethylene-propylene rubber (EPR) is a general term for binary polymers (EPM) obtained by copolymerization of ethylene and propylene or terpolymers (EPDM) obtained by copolymerization of ethylene, propylene and non-conjugated diene monomers. Since the 1980s, it has been the fastest-growing synthetic rubber variety. Its output, production capacity and consumption are second only to styrene-butadiene rubber and polybutadiene rubber, ranking third among the world's seven largest synthetic rubber varieties.

At present, the liquid phase method is the main technology for producing ethylene-propylene rubber, but because the polymerization reaction is carried out in a solvent, the polymerization reaction yield is low, and the polymer mass fraction is generally controlled at 6-9%, and the highest is only 11-14%. Generally, when it exceeds 10%, the viscosity of the reactant increases significantly, which affects the mass transfer and heat transfer of the polymerization system, and violent polymerization will occur in severe cases. In addition, the solution polymerization process also has post-treatment processes such as solvent recovery and purification and catalyst removal, which makes the production process long, and the equipment investment and production costs are high.

Gas-phase method is a newly developed polyolefin production technology. Its process flow is short, no solvent or diluent is needed, and there is almost no discharge of three wastes. It is conducive to the protection of the ecological environment and can greatly reduce the total investment and production cost of the device. Therefore, more and more attention has been paid to it, and it has been applied in the production of ethylene-propylene rubber. In 1999, the former Union Carbide Corporation of the United States (now acquired by Dow Chemical) built a 91kt/a gas-phase ethylene-propylene rubber production plant. The main problem of gas phase production of ethylene propylene rubber is that the initial reaction rate is high during the polymerization process, the heat release is large, the temperature rise is severe in the initial stage of the reaction, and the production temperature is generally higher than the temperature at which the polymer begins to soften, which leads to the polymer Particles agglomerate and bond, and in severe cases, it will lead to loss of fluidization and cause danger. Adding fluidization aids is an effective way to prevent sticky polymers from sticking. The former United Carbon Company prevents the polymer particles from sticking during the reaction process by adding 5-30% (mass fraction) of inert particles such as carbon black, clay or silicon dioxide in the fluidized bed. In addition to preventing the bonding of polymer particles, these inert particles also improve the physical and mechanical properties of EPDM as reinforcing fillers, but there is still room for improvement in performance.

Carbon nanotubes (Carbonnanotubes, CNTs) are one-dimensional nanomaterials, which were discovered by Japanese scientist Iijima in 1991. Carbon nanotubes can be regarded as a seamless, hollow tubular structure composed of ^sp2 hybridized graphite sheets, which can be divided into single-walled carbon nanotubes and multi-walled carbon nanotubes according to the number of carbon layers. (including double-walled carbon nanotubes) have been mass-produced through fluidized bed technology. Carbon nanotubes have excellent mechanical properties, high aspect ratio, thermal stability and electrical conductivity: the average Young's modulus of carbon nanotubes is 1.8TPa, the bending strength is 14.2GPa, and the strength is 100 times higher than that of steel. The density is only one-sixth of that of steel; there is basically no oxidation in the air at 700°C; the conductivity of carbon nanotubes is as high as 1000-2000S/cm, and the current density that can be carried is high. Carbon nanotubes can be used not only as high-value-added functional materials (such as catalyst carriers, electronic components, electromagnetic shielding materials, energy storage materials, and adsorption materials, etc.), but also as reinforcing agents for high-performance composite materials (such as: reinforced rubber , plastics, ceramics and metals, etc.).

Contents of the invention

The present invention is intended to at least partially solve the problem of polymer bonding or improve product performance. For this reason, an object of the present invention is to propose a gas-phase polymerization production method of carbon nanotube-polymer composite material with simple process, high yield and good product quality. Another object of the present invention is to provide a gas-phase polymerization production device for carbon nanotube-polymer composite materials.

The gas phase polymerization production method of carbon nanotube-polymer composite material according to the embodiment of the first aspect of the present invention includes the following steps: providing a catalyst and carbon nanotubes; providing polymerized monomers; the polymerized monomers, catalysts and carbon nanotubes Carbon nanotube-polymer composites were obtained in situ by gas-phase polymerization in an anhydrous and oxygen-free environment.

In one embodiment of the present invention, the outer diameter of the carbon nanotubes is less than 100 nm, and the average aspect ratio is not lower than 100.

In one embodiment of the present invention, the carbon nanotubes are pre-dispersed before gas-phase polymerization, and the average aggregate particle size of the carbon nanotubes after pre-dispersion is less than or equal to 5 μm, and the bulk density is 20-500 kg/m ³ .

In one embodiment of the present invention, the carbon nanotubes are subjected to dehydration, deoxidation and demetallization treatments before gas phase polymerization.

In one embodiment of the present invention, the polymerized monomers include a mixture of one or more of alkenes, alkynes and arenes.

In one embodiment of the present invention, the polymerized monomers include ethylene, propylene and a third comonomer, and the obtained carbon nanotube-polymer composite material is a carbon nanotube-ethylene-propylene rubber composite material.

In one embodiment of the present invention, the reaction temperature of the gas phase polymerization is 25-100° C., and the reaction pressure is 0.3-10 MPa.

In one embodiment of the present invention, the mass ratio of carbon nanotubes, catalyst (without solvent), and polymerizable monomers is 10-10 ⁶ :1:10 ⁴ -10 ⁷ .

In one embodiment of the present invention, part of the carbon nanotubes and all the catalysts are premixed in a solvent before performing gas phase polymerization, and the rest of the carbon nanotubes are added during the gas phase polymerization process, wherein the carbon nanotubes participating in the premixing The mass ratio to the catalyst (without solvent) is 0-10:1.

In one embodiment of the present invention, part of the monomers to be polymerized are pre-polymerized with carbon nanotubes and all catalysts, and then the remaining monomers to be polymerized and pre-polymerized products continue to be mainly polymerized, wherein the carbon input during the pre-polymerization The mass ratio of nanotube:catalyst (without solvent):polymerization monomer is 10-10 ⁶ :1:1-10 ³ .

In one embodiment of the present invention, the reaction temperature of the pre-polymerization is 25-40° C., and the reaction pressure is 0.3-1 MPa; the reaction temperature of the main polymerization is 50-100° C., and the reaction pressure is 1-10 MPa.

In one embodiment of the present invention, the gas phase polymerization is a semi-continuous process or a continuous process.

According to the gas-phase polymerization production device of carbon nanotube-polymer composite material according to the embodiment of the second aspect of the present invention, the production device includes a polymerization monomer raw material inlet, a carbon nanotube filling port, a catalyst filling port, and a material outlet And the stirred tank, ring pipe or fluidized bed of the tail gas outlet.

In one embodiment of the present invention, when the production device is a fluidized bed, the carbon nanotube injection port and the catalyst injection port are located above the gas distributor, and the distance d from the gas distributor satisfies min{50cm, 0.25 H}≤d≤max{100cm,0.5H}, where H is the bed height of the fluidized bed.

In one embodiment of the present invention, the carbon nanotube filling port is adjacent to the catalyst filling port, located above, below or outside the catalyst filling port.

In one embodiment of the present invention, the carbon nanotube injection port and the catalyst injection port are inserted obliquely into the production device from top to bottom, and the angle between them and the vertical direction is less than or equal to 90°.

In one embodiment of the present invention, the discharge port is located in the dense phase region, and the discharge port is lower than the carbon nanotube filling port and the catalyst filling port.

In the carbon nanotube-polymer composite material obtained in situ by gas phase polymerization of the production method and/or production device of the present invention, carbon nanotubes can replace carbon black to prevent polymers from melting and bonding due to exothermic reaction, It can also make the composite material have good strength and electrical and thermal conductivity. The method is especially suitable for gas phase polymerization to produce low softening temperature polymer material (such as ethylene propylene rubber, etc.) compound.

Description of drawings

Fig. 1 is a flow chart of a gas phase polymerization production method of a carbon nanotube-polymer composite material according to an embodiment of the present invention.

Fig. 2 is a flowchart of a gas-phase fluidized bed polymerization production device for carbon nanotube-polymer composite materials according to an embodiment of the present invention.

Figure 3 is a schematic diagram of the positional relationship between the carbon nanotube filling port and the catalyst filling port in Figure 2, wherein (a) the carbon nanotube filling port is located above the catalyst filling port, and (b) the carbon nanotube filling port is located at the catalyst filling port Below the fill port, (b) the carbon nanotube fill port is located outside the catalyst fill port.

Fig. 4 is a material tensile curve diagram of different anti-adhesive additives-ethylene propylene rubber composite samples.

detailed description

Embodiments of the present invention are described in detail below, examples of which are shown in the drawings, wherein the same or similar reference numerals designate the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the figures are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

In describing the present invention, it is to be understood that the terms "center", "longitudinal", "transverse", "length", "width", "height", "upper", "lower", "front", " The orientation or positional relationship indicated by "rear", "vertical", "horizontal", "inner", "outer", "axial", "radial", etc. is based on the orientation or positional relationship shown in the drawings, and is only In order to facilitate the description of the present invention and simplify the description, it does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.

The gas-phase polymerization production method and device of the carbon nanotube-polymer composite material according to the embodiment of the present invention will be described below with reference to the accompanying drawings.

Fig. 1 is a flow chart of the gas phase polymerization production method of carbon nanotube-polymer composite material according to the embodiment of the first aspect of the present invention. As shown in Figure 1, the method may include the following steps: A. providing catalyst and carbon nanotubes; B. providing polymerized monomers; C. polymerizing monomers, catalysts and carbon nanotubes in an anhydrous and oxygen-free environment for gas phase polymerization Obtain carbon nanotube-polymer composites in situ. In this method, the carbon nanotubes are not only used as an anti-adhesive additive to solve the problem of particle bonding during the polymerization reaction, but also used as a product modifier to make the composite material have good strength, electrical and thermal conductivity. The bulk density of carbon nanotubes is only one-third of that of carbon black, so the added mass of carbon nanotubes required to achieve the same anti-adhesive effect is less than that of carbon black, which can save the cost of additives. In addition, since the physical and chemical properties of carbon nanotubes are also superior to traditional materials such as carbon black, the effect of material modification is also more ideal.

It should be noted that since oxygen and water are not conducive to the polymerization reaction, it is necessary to carry out the gas phase polymerization in an anhydrous and oxygen-free environment. In order to ensure that the reaction system does not leak, the method of observing the vacuum degree or pressure with time after vacuuming or filling can be used for system leak detection. After leak detection, use the operation method of switching vacuum several times and filling inert gas (such as: high-purity nitrogen) to remove the water and oxygen in the production device to less than 100ppm, preferably less than 5ppm, before feeding.

It should also be noted that the polymerized monomers are generally provided in the gas phase. However, some liquid-phase polymerization monomers can also be injected into some gas-phase polymerization processes, and its function is to consume the heat of polymerization reaction through liquid-phase gasification, thereby suppressing the rise of the reaction temperature. Since a small amount of liquid-phase monomer is quickly gasified after being added to the production device, it is still gas-phase polymerization, and the principle of the present invention will not be changed.

In one embodiment of the present invention, the carbon nanotube used is a one-dimensional nanotube material formed by sp ² hybridization of carbon atoms, and the tube wall can be single-layer or multi-layer. From the perspective of composite material performance, carbon nanotubes with an outer diameter of less than 100 nm and an average aspect ratio of not less than 100 are preferred.

Due to the severe temperature rise in the initial stage of the polymerization process, it is very important to mix the catalyst and carbon nanotube powder at the moment of entering the production device. In order to improve the utilization rate of carbon nanotubes and the electrical conductivity, thermal conductivity, and strength properties of composite materials, carbon nanotube powders are pre-dispersed before being injected into the production device, and high-speed shearing, ultrasonic-assisted solvent dispersion-freeze drying and other dispersion methods can be used. , the average aggregate particle size of the carbon nanotubes after predispersion is less than or equal to 5 μm, and the bulk density of the carbon nanotubes is 20-500 kg/m ³ .

Due to the strong adsorption performance of carbon nanotubes, in order to avoid the adverse effects of adsorbed moisture and oxygen on the polymerization reaction, carbon nanotubes can be dehydrated and deoxidized by purging high-temperature inert gas before gas-phase polymerization, and the adsorbed Water and oxygen levels drop below 100ppm. And because metal catalysts are needed in the preparation process of carbon nanotubes, in order to avoid the adverse effects of residual metal catalysts on the performance of carbon nanotube-polymer composites, vacuum high temperature or inert flow atmosphere high temperature treatment methods can be used to volatilize the carbon The metal content in the nanotubes was reduced to less than 10 ppm. The actual degree of purification may depend on the requirements of the composite material.

In one embodiment of the present invention, the polymerized monomer may be a mixture including one or more of alkenes, alkynes and arenes. Preferably, the polymerized monomer includes ethylene, propylene and a third comonomer, and the carbon nanotube-polymer composite material obtained at this time is a carbon nanotube-ethylene-propylene rubber composite material.

In one embodiment of the present invention, the mass ratio of carbon nanotubes, catalyst (without solvent), and polymerizable monomers is 10-10 ⁶ :1:10 ⁴ -10 ⁷ . The ideal product can be obtained theoretically according to the feed ratio.

In one embodiment of the present invention, the reaction temperature of the gas phase polymerization should be controlled within the range of 25-65° C., and the reaction pressure within the range of 0.3-10 MPa. The ideal product can be obtained theoretically according to the reaction conditions.

In one embodiment of the present invention, in order to ensure that the catalyst can be fully mixed with the carbon nanotube powder, some carbon nanotubes and all the catalyst can be dispersed in an inert solvent (such as hexane) for premixing, and the rest of the carbon nanotubes The tubes are still added in the form of powder during the gas-phase polymerization process, wherein the mass ratio of the premixed carbon nanotubes to the catalyst (without solvent) is 0-10:1.

In one embodiment of the present invention, part of the monomers to be polymerized are pre-polymerized with carbon nanotubes and all catalysts, and then the remaining monomers to be polymerized and pre-polymerized products continue to be mainly polymerized, wherein the carbon input during the pre-polymerization The mass ratio of nanotube:catalyst (without solvent):polymerization monomer is 10-10 ⁶ :1:1-10 ³ . The pre-polymerization process can fully wrap the carbon nanotubes on the surface of the catalyst particles. It should be noted that not all the polymerized monomers put into the prepolymerization process are converted into polymers, and usually the mass ratio of the polymer obtained after prepolymerization to the catalyst is only 1-200:1. In addition, it should be noted that all the catalysts are consumed in the pre-polymerization, but not all the carbon nanotubes are necessarily consumed. Therefore, it is determined whether to continue to add carbon nanotubes during the main polymerization process according to the carbon nanotube content requirements of the final composite material.

In one embodiment of the present invention, the reaction conditions of pre-polymerization and main polymerization may be different. Taking the production of carbon nanotube-ethylene propylene rubber composite materials as an example, the reaction temperature of pre-polymerization is 25-40°C, and the reaction pressure is 0.3-1MPa; the reaction temperature of main polymerization is 50-100°C, and the reaction pressure is 1-10MPa.

In one embodiment of the present invention, the gas phase polymerization can be a semi-continuous process (catalyst and carbon nanotubes are added intermittently, polymerization monomer is added continuously, and the product of carbon nanotube-polymer composite material is unloaded intermittently), and it can also be continuous Process (continuously adding catalyst, carbon nanotubes and polymerized monomers, while continuously discharging the product of carbon nanotube-polymer composite material).

The gas phase polymerization production device of carbon nanotube-polymer composite material in the embodiment of the second aspect of the present invention is that the device includes a carbon nanotube filling port, a catalyst filling port, a polymerization monomer raw material inlet, a material outlet, and an exhaust gas outlet. stirred tank, loop or fluidized bed. Figure 2 is a schematic diagram of a gas-phase polymerization production device for carbon nanotube-polymer composite materials in the form of a fluidized bed. As shown in Fig. 2, the interface of the fluidized bed production device includes: polymer monomer raw material inlet 1, carbon nanotube filling port 2-1, catalyst filling port 2-2, material outlet 3 and tail gas outlet 4. It should be noted that technicians can also make the following detailed design according to actual needs: a gas distributor is installed at the lower part of the production device, and the purified polymerized monomer enters the fluidized bed evenly from the gas distributor. Polymerization monomer is used as raw material gas to fluidize the catalyst particles while the polymerization reaction occurs, and the heat of reaction is removed by the heat difference of the gas entering and leaving the production device or the gasification of part of the liquid phase feed. The top of the production unit is designed with an enlarged shape to facilitate particle deposition and reduce the amount of particles entrained in the gas. The unpolymerized polymerized monomer and diluent gas are separated from solid particles by a gas-solid separator and recycled. For easy maintenance, the gas-solid separator can be installed outside the production device, and the separated solid particles can be recycled back to the production device. The production rate depends on the injection rate of the catalyst and the concentration of the monomer in the circulating system, usually only the injection rate of the catalyst controls the production rate.

In one embodiment of the present invention, when the production device is a fluidized bed, the carbon nanotube injection port 2-1 and the catalyst injection port 2-2 are located above the gas distributor, and the distance from the gas distributor is not less than 50cm or a quarter of the bed height of the fluidized bed (take the smaller value of the two data), not higher than 100cm or one-half of the bed height of the fluidized bed (take the larger value of the two data).

In one embodiment of the present invention, the catalyst filling port 2-1 and the carbon nanotube filling port 2-2 are inserted obliquely into the production device from top to bottom, and the included angle with the vertical direction is less than or equal to 90°. That is, the production unit can be inserted horizontally. It is generally preferred to insert at an angle of less than 45 degrees from the vertical.

In one embodiment of the present invention, the carbon nanotubes are carried into the production device by gas flow. In order to ensure that the carbon nanotube powder is quickly wrapped on the surface of the catalyst particles, the carbon nanotube filling port 2-1 should be adjacent to the catalyst filling port 2-2. The carbon nanotube filling port 2-1 can be located above, below or outside the catalyst filling port 2-2, as shown in FIG. 3 . Wherein, when the carbon nanotube filling port 2-1 is located outside the catalyst filling port 2-2, a sleeve structure is adopted, the catalyst is injected from the tube, and the carbon nanotubes are brought in by the gas flow from the shell. It should be noted that although the filling ports shown in FIG. 3 are all filling ports in the horizontal direction, this is only for the convenience of illustration and should not be regarded as a limitation of the present invention. In practical application, it can also be adjusted to a filling port in an inclined direction as required.

In one embodiment of the present invention, the discharge port 3 is located in the dense phase region, and the discharge port 3 is lower than the carbon nanotube filling port 2-1 and the catalyst filling port 2-2. Setting the discharge port 3 in the dense phase area is beneficial to extract larger composite material particles.

According to the method of the present invention and/or the carbon nanotube-polymer composite material prepared in situ by gas phase polymerization using the device of the present invention has excellent electrical and mechanical properties, which is the effect that the addition of anti-sticking agents such as carbon black does not have . Table 1 shows the conductivity test results of the ethylene-propylene rubber composite samples assisted by different types of anti-adhesive additives with different contents.

The conductivity test results of different samples in table 1

It can be seen from Table 1 that the resistivity of the composite material decreases sharply with the increase of the carbon nanotube content. The carbon nanotube-ethylene propylene rubber composite material with a carbon nanotube content of 2.25% (mass percentage, the same below) can already meet the antistatic standard (resistivity 10 ⁴ -10 ⁷ Ωcm). When the carbon nanotube content is higher than 6.76%, the composite material has become a conductive material (resistivity is less than 10 ⁴ Ωcm). The conductivity of carbon nanotube-EPDM composites is better than that of conductive carbon black-EPDM composites. The resistivity of the composite material with 6.76% carbon nanotube content is similar to that of the composite material with 20.04% conductive carbon black content. That is, in order to obtain conductive composite materials, the amount of conductive carbon black added is 3 times that of carbon nanotubes. The excellent conductivity of carbon nanotubes-ethylene propylene rubber composites stems from the fact that carbon nanotubes are one-dimensional tubular nanomaterials. In addition to their excellent electrical conductivity, carbon nanotubes can be entwined with each other. Compared with spherical conductive carbon Black is easier to form a conductive network.

Figure 4 shows the test results of the mechanical properties of some of the above samples. It can be seen that both carbon nanotubes and conductive carbon black can enhance the mechanical properties of ethylene-propylene rubber. Appropriate addition of carbon nanotubes or conductive carbon black can increase the tensile strength and elongation at break of ethylene-propylene rubber. When the carbon nanotube content was 6.76% or the conductive carbon black content was 20.04%, the tensile strength of the composite was 1.3 and 1.2 times that of the blank sample, and the elongation at break increased by 17% and 40%, respectively. In the case of basically the same reinforcing effect, the amount of carbon nanotubes is only one-third of that of conductive carbon black. When the carbon nanotube content reaches 14.24%, the composite material is more rigid, showing that the tensile strength is 2.5 times that of the blank sample, while the elongation at break is only 15% of that of ethylene-propylene rubber. Such composite materials are stronger but less elastic and can be used to make parts that require strength.

In order to enable those skilled in the art to better understand the present invention, the applicant introduces five embodiments in detail below. It should be noted that the embodiments are only some preferred examples, and the protection scope of the present invention shall be determined by the claims of the application.

Example 1

The carbon nanotube-ethylene propylene rubber composite material is produced by polymerization in a gas-phase stirred tank.

Multi-walled carbon nanotubes with an average outer diameter of 20 nm and an average length-to-diameter ratio greater than 100 are selected. Purify carbon nanotubes by vacuum high-temperature treatment at a temperature of 1800°C and a vacuum higher than 10 ^-2 Pa for 5 hours; use high-speed shear to disperse the purified carbon nanotubes at a speed of 20,000 rpm , the time is 5 minutes, the average aggregated particle size of the dispersed powder is not more than 5 μm, and the bulk density of the powder is 20 kg/m ³ . 2.0 g of the purified and dispersed carbon nanotube powder was added into a stirred tank reactor, and 120 g of polypropylene particles (used as a matrix bed) were placed in the reactor in advance, with an average particle diameter of 2.5 mm. Adding to the reactor adopts the operation method of switching vacuum and filling high-purity nitrogen several times to reduce the concentration of water vapor and oxygen in the reactor to below 100ppm. The temperature of the stirred tank water bath jacket was set at 50° C., 5.2 mg of titanium-based catalyst and 3 mmol of triethylaluminum were successively added to the stirred tank reactor, and a mixed gas of ethylene and propylene was introduced (the molar ratio of ethylene to propylene was 1.7). The pressure in the reactor was maintained at 0.3 MPa (absolute pressure), and after 1 hour of reaction, 9.7 g of carbon nanotube-ethylene-propylene rubber composite was obtained, and the product was in the form of black powder, wherein the content of carbon nanotubes was 14.2%. The average particle size of the powder product is 100μm, which is easy to separate from the millimeter-sized polypropylene particles.

Example 2

Carbon nanotube-ethylene propylene rubber composites are produced by gas-phase bulk polymerization in the pre-polymerization reactor and the main polymerization reactor.

First, the carbon nanotube powder is purified at high temperature in a gas-phase fluidized bed at a temperature of 1800° C. in a flowing nitrogen atmosphere. Continuously feed the purified carbon nanotubes into the pre-polymerization gas-solid fluidized bed reactor. Under the conditions of 25°C and 0.3MPa, the catalyst and ethylene and propylene monomers are pre-polymerized. The mass ratio of the carbon nanotubes and the catalyst (without solvent) added to the pre-polymerization reactor is 10, and the catalyst (without solvent) and The mass ratio of the monomers is 10 ^-3 . The mass ratio of the polymer grown in the prepolymerization tank to the catalyst (without solvent) was 1. The solid phase (carbon nanotubes + catalyst + a small amount of polymer) in the prepolymerization reactor is continuously introduced into the main polymerization gas-solid fluidized bed reactor. Under the conditions of 50°C and 1MPa, feed ethylene, propylene and the third monomer for polymerization, the mass ratio of prepolymer to monomer is 10 ^-5 , and continuously discharge carbon nanotubes from the discharge port above the distributor- Ethylene Propylene Rubber Composite Products.

Example 3

Carbon nanotube-ethylene propylene rubber composites are produced by gas-phase bulk polymerization in the pre-polymerization reactor and the main polymerization reactor.

The prepolymerization reactor, the main polymerization reactor and the carbon nanotube pretreatment method are the same as in Example 2. The purified carbon nanotubes are continuously fed into the prepolymerization reactor. The catalyst and ethylene and propylene monomers are pre-polymerized at 40°C and 1 MPa. The mass ratio of carbon nanotubes to the catalyst (without solvent) added to the pre-polymerization reactor is 10 ⁶ , and the catalyst (without solvent) and The mass ratio of the monomers is 10 ^-3 . The ratio of polymer to catalyst mass grown in the prepolymerization tank was 200. The solid phase (carbon nanotubes + catalyst + small amount of polymer) in the pre-polymerization reactor was continuously introduced into the main polymerization reactor. Under the conditions of 65°C and 10MPa, ethylene, propylene and the third monomer are fed to polymerize, the mass ratio of prepolymer to monomer is 10 ^-4 , and carbon nanometers are continuously discharged from the discharge port above the distributor. Tube - Ethylene Propylene Rubber Composite Product.

Example 4

Production of carbon nanotube-polypropylene composites by polymerization in a gas-phase fluidized bed reactor.

The carbon nanotube samples were ground to fine powder and treated at 1500 °C for 10 h under flowing Ar atmosphere. The fluidized bed reactor was replaced with flowing nitrogen to the content of moisture and oxygen below 100ppm, while nitrogen was heated to raise the temperature of the reactor to 70°C and maintain a pressure of 10MPa at the top of the fluidized bed. The nitrogen gas is replaced by propylene raw material gas and enters the reactor from the bottom of the fluidized bed through a gas distributor. Catalysts and carbon nanotubes are injected into the fluidized bed using a casing structure. Catalyst active components and additives are dissolved in cyclohexane, and injected into the fluidized bed reactor from the center tube of the sleeve at an angle of 30 degrees to the vertical direction, and the carbon nanotubes are carried by Ar from the shell of the sleeve to the same Angle injection reactor. In order to facilitate the full and rapid mixing of carbon nanotubes and catalysts, some carbon nanotubes are dispersed in cyclohexane solution and added to the reactor together with the catalyst. The mass of this part of carbon nanotubes is 10 times the mass of the catalyst (without solvent). The mass ratio of the total amount of carbon nanotubes added to the reactor to the catalyst (without solvent) is 10 ⁶ , and the mass ratio of the catalyst (without solvent) to monomer is 10 ^-7 . Catalyst and carbon nanotube injection ports are located 50 cm above the gas distributor. The height of the fluidized bed is greater than 100cm. There is a solid material discharge port (ie discharge port) 20 cm above the distributor, and the carbon nanotube-polypropylene composite material product is discharged intermittently or continuously.

Example 5

Production of carbon nanotube-polyethylene composites by gas phase polymerization in a loop reactor.

The reaction temperature is 100° C., the reaction pressure is 10 MPa, the mass ratio of carbon nanotubes to catalyst (without solvent) is 10, and the mass ratio of catalyst (without solvent) to ethylene monomer is 10 ⁻⁷ .

In the description of this specification, descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific examples", or "some examples" mean that specific features described in connection with the embodiment or example , structure, material or characteristic is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the described specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples and features of different embodiments or examples described in this specification without conflicting with each other.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention, those skilled in the art can make the above-mentioned The embodiments are subject to changes, modifications, substitutions and variations.

Claims (25)

1. the gas-phase polymerization production method of CNT-polymer composite, it is characterised in that comprise the following steps:

Catalyst and CNT are provided；

Polymerization monomer is provided；

Described polymerization monomer, catalyst and CNT carry out under anhydrous and oxygen-free environment gas-phase polymerization obtain in situ CNT- Polymer composite, wherein, before carrying out gas-phase polymerization by part CNT with whole catalyst common distribution molten Agent premixes, the addition when carrying out gas-phase polymerization processes of remaining CNT.

2. the method for claim 1, it is characterised in that the external diameter of described CNT is less than 100nm, averagely Draw ratio is not less than 100.

3. the method for claim 1, it is characterised in that described CNT before gas-phase polymerization through pre-dispersed place Reason, the average aggregate particle diameter of pre-dispersed rear described CNT is less than or equal to 5 μm, and bulk density is 20-500kg/m³。

4. the method for claim 1, it is characterised in that described CNT passes through dehydration before gas-phase polymerization, takes off Oxygen and demetalization process.

5. the method as described in any one of claim 1-4, it is characterised in that the reaction temperature of described gas-phase polymerization is 25-100 DEG C, reaction pressure is 0.3-10MPa.

6. the method for claim 1, it is characterised in that CNT, catalyst, the quality of polymerization monomer three Ratio is 10-10⁶:1:10⁴-10⁷, wherein, described catalyst does not contains solvent.

7. method as claimed in claim 6, it is characterised in that the mass ratio of the CNT and catalyst that participate in premix is 0-10:1, wherein, described catalyst does not contains solvent.

8. the method for claim 1, it is characterised in that described gas-phase polymerization is semi-continuous process or continuous process.

9. the gas-phase polymerization production method of CNT-polymer composite, it is characterised in that comprise the following steps:

Catalyst and CNT are provided；

Polymerization monomer is provided；

Described polymerization monomer, catalyst and CNT carry out under anhydrous and oxygen-free environment gas-phase polymerization obtain in situ CNT- Polymer composite, wherein, first carries out prepolymerization by partially polymerized monomer with CNT and whole catalyst, then will Residue polymerization monomer proceeds main polymerization with prepolymerization product.

10. method as claimed in claim 9, it is characterised in that the external diameter of described CNT is less than 100nm, averagely Draw ratio is not less than 100.

11. methods as claimed in claim 9, it is characterised in that described CNT before gas-phase polymerization through pre-dispersed Processing, the average aggregate particle diameter of pre-dispersed rear described CNT is less than or equal to 5 μm, and bulk density is 20-500kg/m³。

12. methods as claimed in claim 9, it is characterised in that the process dehydration before gas-phase polymerization of described CNT, Deoxidation and demetalization process.

13. methods as claimed in claim 9, it is characterised in that described polymerization monomer includes in alkene, alkynes and aromatic hydrocarbons The mixture of one or more.

14. methods as claimed in claim 13, it is characterised in that described polymerization monomer includes that ethylene, propylene and the 3rd are altogether Poly-monomer, it is thus achieved that described CNT-polymer composite be CNT-EP rubbers composite.

15. methods as described in any one of claim 9-14, it is characterised in that the reaction temperature of described gas-phase polymerization is 25-100 DEG C, reaction pressure is 0.3-10MPa.

16. methods as claimed in claim 9, it is characterised in that CNT: catalyst: the mass ratio of polymerization monomer For 10-10⁶:1:10⁴-10⁷, wherein, described catalyst does not contains solvent.

17. methods as claimed in claim 16, it is characterised in that the CNT put in pre-polymerization process: catalyst: The mass ratio of polymerization monomer is 10-10⁶:1:1-10³, wherein, described catalyst does not contains solvent.

18. methods as claimed in claim 17, it is characterised in that described prepolymerized reaction temperature is 25-40 DEG C, instead Answering pressure is 0.3-1MPa；The reaction temperature of described main polymerization is 50-100 DEG C, and reaction pressure is 1-10MPa.

19. methods as claimed in claim 9, it is characterised in that described gas-phase polymerization is semi-continuous process or continuous process.

The gas-phase polymerization process units of 20. 1 kinds of CNT-polymer composites, it is characterised in that described process units Be include being polymerized raw material monomer entrance, CNT filler, catalyst filler, discharging opening and the stirred tank of offgas outlet, Endless tube or fluid bed.

21. devices as claimed in claim 20, it is characterised in that when described process units is fluid bed, CNT Filler and catalyst filler are positioned on gas distributor, and distance d away from gas distributor meets Min{50cm, 0.25H}≤d≤max{100cm, 0.5H}, wherein H is fluidized bed layer height.

22. devices as described in claim 20 or 21, it is characterised in that urge described in described CNT filler next-door neighbour Agent filler, is positioned at above described catalyst filler, lower section or outside.

23. devices as claimed in claim 22, it is characterised in that CNT filler and catalyst filler from upper and Declivity inserts process units, with vertical direction angle less than or equal to 90 °.

24. devices as claimed in claim 20, it is characterised in that described discharging opening is positioned in emulsion zone, and described discharging Mouth is less than described CNT filler and catalyst filler.

25. 1 kinds of CNT-EP rubbers composites, it is characterised in that described CNT-EP rubbers composite Gas-phase polymerization production method with the CNT-polymer composite in claim 1-8 or according to any one of 9-19 Or prepared by the gas-phase polymerization process units of the CNT-polymer composite according to any one of claim 20-24.