WO2017066937A1 - Method for preparing graphene-polyester nanocomposite fiber - Google Patents

Abstract

A method for preparing a graphene-polyester nanocomposite fiber, comprising the following steps: a step of preparing a graphene-polyester composite masterbatch and a step of preparing a graphene-polyester nanocomposite fiber from the composite masterbatch. In addition, the excellent mechanical property and functional characteristics of graphene endow the nanocomposite fiber with functionalities such as high strength and antistatic property. Good dispersion and interfacial compatibility of surface-modified and modified graphene in a polyester polymer matrix enable the graphene to be efficiently and uniformly compounded with a polyester chip base material.

Description

Method for preparing graphene-polyester nano composite fiber Technical field

The invention relates to a preparation method of graphene-polyester nano composite fiber.

Background technique

Graphene is the thinnest two-dimensional nanomaterial known at present. Its crystal lattice is a hexagon formed by six carbon atoms, and its thickness is an atomic layer. The carbon atoms are connected by s bond, and the bonding mode is sp. ² Hybridization, these s bonds give graphene excellent mechanical properties and structural rigidity, and graphene is 100 times stronger than the best steel. Graphene is highly conductive and is the world's least resistive material; graphene is also a very good antibacterial material. Based on the mechanical properties of graphene, graphene can be added to the polymer matrix, which can improve the mechanical properties of the material, such as tensile strength, modulus, hardness, etc.; based on the excellent electrical properties of graphene, can be added to In the composite material, the insulator becomes a conductive material, and the effect is very obvious; it is also possible to add graphene to the composite material to increase the functionality that the composite material itself does not have, such as antibacterial property, flame retardancy, radiation resistance, and the like. Therefore, graphene nanocomposites have unparalleled advantages over other nanocomposites.

Polyester is an important variety in synthetic fibers. It is made from polyethylene terephthalate (PET), which is made by spinning and post-treatment. Polyester is the world's largest and most widely used synthetic fiber variety, with polyester accounting for more than 60% of the world's synthetic fiber production. It is widely used in textiles such as clothing, bedding, various decorative fabrics, special fabrics for defense and military industry, and other industrial fiber products. The production of traditional high-strength polyester yarns needs to be first viscous by polyester chips and then produced by polyester. The equipment required for this method is complicated, expensive, complicated in production process, and greatly increases production costs. At present, it is a simple and cost-effective preparation method to prepare high-performance polyester fiber by adding nanofiller to polyester polyester matrix. Liu Shanhe of Anhui Guoxing Biochemical Co., Ltd. invented a PET composite material containing attapulgite (Chinese invention patent CN103756265A), but the shortcoming of this method is that it is difficult to completely and uniformly disperse the attapulgite. The performance and subsequent use of PET composites are greatly limited to PET substrates. Yu Tianshi of Jiangnan University invented an antistatic nano-titanium dioxide composite polyester monofilament (Chinese invention patent CN104278350A), but the method is inefficient and unsuitable for large-scale production, and the prepared polyester monofilament has low strength and limited practicality. . Therefore, the current methods for preparing polyester nanocomposite fibers are mostly concentrated in the basic research and small trial exploration stages. The overall performance of nanocomposite fibers is not high, and there is no prospect of industrial production. Practical application value.

Summary of the invention

In view of the defects in the prior art, the object of the present invention is to provide a method for preparing graphene-polyester nanocomposite fibers; graphene has a perfect two-dimensional crystal structure, and its crystal lattice is composed of six carbon atoms. Hexagon, the thickness is an atomic layer. The carbon atoms are connected by s bonds, and the bonding mode is sp ² hybridization. These s bonds impart excellent mechanical properties and structural rigidity to graphene. Therefore, it is a good choice to use graphene to increase the breaking strength of polyester. The best choice for graphene-polyester nanocomposite fibers is graphene oxide functionalized by halogenated hydrocarbons. The functionalization of graphene oxide and polyester polyester is better, which helps graphene in polyester polyester. The matrix is uniformly dispersed to increase the strength of the graphene-polyester nanocomposite fiber. Ordinary industrial grade polyester polyester chips are dried and then composite granulated with graphene of different compositions, and then graphene-polyester nanocomposite fibers are prepared on a melt spinning machine.

The invention is a method for providing a novel nano-composite fiber for the existing industrial production of polyester filament yarn method, and compared with other existing methods: the process is extremely simple, the material performance is excellent and the price is low. In addition, graphene is easy to be uniformly compounded with the polyester polyester chip substrate due to its excellent mechanical properties and good interfacial compatibility with the polyester polyester polymer after modification of the modified graphene.

The invention is achieved by the following technical solutions:

The invention provides a preparation method of graphene-polyester nano composite fiber, comprising the following steps: a preparation step of graphene-polyester polyester composite master batch and a step of preparing the composite master batch into graphene-polyester nano composite fiber .

Preferably, the preparing step of the graphene-polyester polyester composite masterbatch specifically comprises: mixing the polyester polyester chips with graphene at a high speed, twin-screw extrusion, granulation, and obtaining.

Preferably, the type of graphene is selected from the group consisting of chemical vapor deposition (CVD) for preparing graphene, carbon dioxide supercritical expansion stripping graphene, chemically oxidized and stripped graphene oxide, coupling agent for modifying graphene oxide, and cationic surface activity. Agent modified graphene oxide, long-chain halogenated hydrocarbon modified graphene oxide (such as brominated dodecane modified graphene oxide, hexadecane bromide modified graphene oxide, brominated octadecane modified Graphene oxide, etc., high-temperature thermal expansion of reduced graphene oxide, low-temperature thermal expansion of reduced graphene oxide, electrochemical stripping of graphene, modified electrochemical stripping graphene, mechanical ball-milling stripping graphene, three-roll mill mechanical stripping graphene One or several of them.

Preferably, the polyester polyester chip needs to be dried before use;

Further, the moisture content in the dried polyester polyester chip is 50 ppm or less, preferably less than 30 ppm.

Moisture in polyester polyester chips is extremely detrimental to spinning. Undried polyester chips usually have a moisture content of about 0.4%. The moisture in the polyester chips is removed to avoid the violent hydrolysis of the polyester polymer during the spinning process. Therefore, it is extremely important to dry the polyester polyester chips.

Preferably, the mass ratio of the polyester polyester chip to the graphene is 100: (0.1-20).

Preferably, the high speed mixing mode comprises agitation at a speed of 10,000-25,000 rpm for 0.5-4 min.

In carrying out the above steps, the polyester polyester chips and graphene are dried, then cooled to room temperature, and subjected to a subsequent high-speed mixing step.

Preferably, in the twin-screw extrusion, the temperatures of one zone, two zones, three zones, four zones and five zones of the twin-screw extruder are: 265 ° C, 268 ° C, 270 ° C, 268 ° C, 265 ° C. If the temperature of each zone of the twin-screw extruder is low, the polyester polyester cannot be completely melted in the twin-screw extruder, the resistance during extrusion is large, and the polyester polyester which is not completely melted has poor fluidity, and graphene is in Uneven dispersion in polyester polyester; if the temperature of each zone of twin-screw extruder is higher, the degradation rate of polyester polyester at higher temperature will increase, which will affect the performance of subsequent products. Therefore, the temperature given by the patent of the present invention is relatively suitable. On the one hand, the graphene can be uniformly dispersed in the polyester polyester, and the composite master batch can be stably prepared; on the other hand, the degradation of the polyester polyester can be prevented.

More specifically, the step of twin-screw extrusion and granulation is specifically as follows: the polyester polyester chips and graphene are stirred in a common pulverizer at a speed of 10,000 to 25,000 rpm for 0.5 to 4 minutes, and the polyester polyester The size of the sliced and graphene reaches 18-200 mesh, then the pre-mixed polyester polyester chips and graphene are added to the feeding bin of the twin-screw extruder, and the main machine and the feeding bin are discharged. After the strips are uniform in color and free of bubbles, the strips are sent to a pelletizer for pelletizing, and the pellets are fed at the discharge port of the pelletizer. The masterbatch is the prepared graphene-polyester polyester compound. Masterbatch.

Preferably, the step of preparing the composite masterbatch into a graphene-polyester nanocomposite fiber comprises: spinning the graphene-polyester polyester composite masterbatch, then slowly cooling, forming, oiling, stretching and winding That is, a graphene-polyester nanocomposite fiber is produced.

Further, the step of preparing the composite master batch into a graphene-polyester nano-composite fiber comprises: drying the graphene-polyester polyester composite master batch, and sending the dried composite master batch into the feeding bin , through the screw extruder into the spinning box for spinning, and then through the slow cooling device, the side blow cooling to form, oil, through the first roller, the second roller, the third roller and the last winding to produce graphene - Polyester nanocomposite fiber.

Preferably, the drying uses a polyester dryer, the drying temperature is 120-140 ° C, the time is not less than 4 hours, and the moisture content of the composite masterbatch after drying is less than 50 ppm.

Preferably, the temperatures of one, two, and three zones of the screw extruder are 280 ° C, 283 ° C, and 285 ° C, respectively.

Preferably, the spinning box has a temperature of 285 °C.

Preferably, the slow cooling device has a temperature of 290 ° C, including an annular retarder.

Preferably, the side blowing device has a temperature of 22 ° C, a humidity of 75%, and a wind speed of 0.4 m/s.

Preferably, the oiling oil tanker has a rotational speed of 15 r/min.

Preferably, the temperatures of the pair of rolls 1, the pair of rolls 2, and the pair of rolls 3 are 85 ° C, 110 ° C, and 125 ° C, respectively.

The specific preparation process is shown in Figure 2, and the production process parameters are shown in Table 1. The prepared graphene-polyester nanocomposite fiber is shown in Fig. 3.

We use halogenated hydrocarbons, functionally modify and modify graphene oxide, and then combine the modified graphene and polyester polyester in a twin-screw extruder to prepare graphene-polyester nanocomposite masterbatch, and finally compound The graphene-polyester nanocomposite fiber can be obtained by spinning the masterbatch directly on a melt spinning machine. The modification and the modified composite method are simple and easy, the graphene is uniformly dispersed in the polyester polyester, the interface compatibility is good, and it is suitable for mass production on the existing spinning device. The graphene-polyester nanocomposite fiber prepared by the composite masterbatch by the melt spinning machine has high strength, and has the functions of antibacterial, antistatic, anti-radiation, flame retardant, smooth and cool.

Polyester polyester chips do not need to undergo complex viscosity-increasing reactions, but can be combined with graphene for high-strength strength, and at the same time give the composite fiber multiple functions. This method is simple and easy to work with. The polyester melt spinning industrial production equipment and process technology are seamlessly connected, and high-performance and functional graphene-polyester nano-composite fibers can be prepared without modifying and upgrading existing equipment. In addition, the amount of graphene nanofiller added to the nanocomposite fiber is extremely small, so that the composite material has low cost, is easy to mass-produce, and has good operability and industrialization feasibility.

The graphene is high-temperature thermal expansion graphene and various functionalized modified and modified graphene, and the method is a twin-screw extruder for preparing graphene-polyester polyester nanocomposite masterbatch and polyester melt spinning (FDY spinning) Silk stretching one step method). Polyester polyester chips do not need to undergo complex viscosity-increasing reaction, but can be achieved by combining the spinning with graphene to achieve higher strength. This method is simple and easy, and can be used in the existing industrial production process of polyester melt spinning. The seams allow for the preparation of high performance and functional graphene-polyester nanocomposites without the need to retrofit and upgrade existing equipment. In addition, the amount of graphene nanofiller required in the nanocomposite fiber is extremely small, thereby saving cost and easily achieving mass production, and the feasibility is good. The problem of dispersion and compatibility of graphene in a polyester polyester matrix is the key to obtaining high performance nanocomposite fibers. Since the surface energy of the two-dimensional honeycomb structure of graphene is high, curling, lamination and agglomeration are liable to occur, which affects the uniform dispersion in the polyester polyester matrix, thereby seriously affecting the performance of the prepared composite fiber. Therefore, in order for graphene to truly exert its high performance and functional function in composite fiber materials, it is first necessary to solve the problem of uneven dispersion of graphene in the polyester polyester matrix, and only the graphene is uniformly dispersed in the polyester. Polyester base In the bulk material, the advantages of two-dimensional enhancement and low addition of graphene can be fully utilized, and the structural properties of the composite fiber material are uniform. If the uniform dispersion of graphene is not achieved in the composite fiber material, the composite material is prone to defects during the load transfer process, which greatly reduces the overall performance of the composite fiber material. How to improve the compatibility of graphene and polymer has always been the primary problem faced by researchers in the preparation of polymer composites. Graphene as a polymer-based reinforcement must be firmly bonded to the polymer molecules so that the stresses on the substrate are effectively transferred to the graphene sheets without interfacial sliding of the matrix and the nanofillers. To a certain extent, the dispersibility of graphene in the preparation of graphene-polyester nanocomposite fibers and its binding force with the polymer matrix are interrelated, that is, only by achieving uniform dispersion of graphene, graphene and Firmly linked and tightly bonded polyester polyester matrix. In the present invention, by using graphene which is simply modified and modified on the surface, a stable interaction between graphene and polyester polyester molecules is formed, and the interface bonding force between the two is large, and the excellent mechanical properties and functions of graphene are fully exerted. Properties to obtain high performance graphene-polyester nanocomposite fibers. Similar to montmorillonite, graphene is a two-dimensional sheet-like nanomaterial, which makes it an excellent nano-reinforcing material. At the same time, graphene itself also has high mechanical properties, and the nanocomposite fiber prepared by using the nanofiller will exhibit more excellent mechanical properties. Therefore, compared with the prior art, the breaking strength of the graphene-polyester nanocomposite fiber is greatly improved. The average rupture strength of graphene-polyester nanocomposite fibers is increased by 60% compared to conventional polyester. In addition, the high electrical conductivity, thermal conductivity and barrier properties of graphene will also give graphene-polyester nanocomposite fibers antistatic, heat, flame retardant and antibacterial properties.

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

1. Graphene is a two-dimensional honeycomb crystal composed of carbon atoms. It has unparalleled mechanical properties and electrical, thermal, antibacterial and anti-radiation functions. It is the thinnest and strongest material known at present. Therefore, compared with the prior art, the breaking strength of the graphene-polyester nanocomposite fiber is greatly improved.

2, melt blending to prepare graphene-polyester polyester masterbatch in a twin-screw extruder, the preparation of composite masterbatch is simple and easy, no need to add additional equipment, low production costs, so the use of melt blending is very beneficial Achieve industrialized continuous production. And melt blending generally does not require the use of solvents, and there is no exhaust gas and waste liquid discharge during the preparation process, which is an environmentally friendly green nanocomposite process.

3. The method adopts FDY spinning and stretching one-step method for spinning, and the process changes the process route of the conventional two-step method for manufacturing the fully drawn yarn into a one-step process route in which spinning and stretching are continuously performed, not only greatly The production process has been shortened, infrastructure investment has been reduced, and product quality, production efficiency and volume of packaging have been greatly improved. In addition, the POY wire can be directly prepared by a melt spinning machine, and then subjected to a texturing machine to obtain a stretched graphene-polyester nano-composite fiber material for use and performance in the field of other protective materials such as high-performance safety gloves.

4, polyester polyester chips do not need to undergo a complex viscosity-increasing reaction, but simply with the uniform dispersion of graphene - effective composite - melt spinning can achieve higher strength. The high-strength wire prepared by the method has the advantages of antistatic, antibacterial, anti-radiation, flame retardant, smooth and cool. The method is simple, and does not require modification of the existing industrial equipment for polyester spinning, simple operation, low production cost, easy industrialization and large-scale preparation. The breaking strength of ordinary polyester filament is usually around 3.1 cN/dtex, and the graphene-polyester nanocomposite fiber prepared by the patent technology has a breaking strength of 5.0 cN/dtex or more and a strength increase of 60%.

DRAWINGS

Other features, objects, and advantages of the present invention will become apparent from the Detailed Description of Description

Figure 1 is a process flow for preparing a graphene-polyester polyester masterbatch;

2 is a process flow for preparing a graphene-polyester nano-composite fiber;

Figure 3 is a physical diagram of a graphene-polyester nanocomposite fiber product.

detailed description

The invention will now be described in detail in connection with specific embodiments. The following examples are intended to further understand the invention, but are not intended to limit the invention in any way. It should be noted that a number of variations and modifications may be made by those skilled in the art without departing from the inventive concept. These are all within the scope of protection of the present invention.

Table 1 Process parameters of graphene-polyester nanocomposite fiber production

The following examples were carried out under the parameter settings as described in Table 1.

Example 1

The present embodiment provides a method for preparing a graphene-polyester nano composite fiber, comprising the steps of: preparing a graphene-polyester polyester composite masterbatch and preparing the composite masterbatch into a graphene-polyester nanocomposite fiber. step;

Step 1. The preparation step of the graphene-polyester polyester composite masterbatch (see Fig. 1) comprises: mixing the polyester polyester chip with graphene (the mass ratio of the two is 100:0.1) at a high speed, twin-screw extrusion, making Grain, that is:

Wherein the type of the graphene is selected from the group consisting of chemically oxidized and exfoliated graphene oxide, and then modified and modified by octadecyl bromide;

The polyester polyester chip needs to be dried before use; the moisture content in the dried polyester polyester chip is below 50 ppm;

In the above steps, the polyester polyester chips and graphene are dried, then cooled to room temperature, and then subjected to a subsequent high-speed mixing step; the high-speed mixing method is stirred at 10,000 rpm for 4 minutes, and the equipment used is a pulverizer. The particle size of the mixed material is 18-200 mesh.

In the twin-screw extrusion process, the temperature of one zone, two zones, three zones, four zones and five zones of the twin-screw extruder are: 265 ° C, 268 ° C, 270 ° C, 268 ° C, 265 ° C.

Step 2: preparing the composite masterbatch into a graphene-polyester nanocomposite fiber (see FIG. 2) comprises: spinning the graphene-polyester polyester composite masterbatch, then slowly cooling, forming, oiling, Stretching and winding, that is, making graphene-polyester nanocomposite fibers;

More specifically, the step of preparing the composite master batch into a graphene-polyester nano-composite fiber comprises: drying the graphene-polyester polyester composite master batch, feeding it into a feeding bin, and extruding through a screw The machine enters the spinning box for spinning, and then passes through the slow cooling device, the side blows the cooling to form and oil, and the graphene-polyester nano-composite fiber is formed by the first roller, the second roller, the third roller and the last winding. ;

The drying treatment is carried out by a polyester dryer, the drying temperature is 120-140 ° C, the drying time is 4 hours or more, and the moisture content of the composite master batch after drying is less than 50 ppm.

The graphene-polyester nanocomposite fiber prepared in this embodiment is shown in FIG.

Example 2

This embodiment is a modification of Embodiment 1, and also provides a method for preparing graphene-polyester nanocomposite fibers, except that the type of graphene is selected from the group consisting of reduced-temperature thermal expansion reduced graphene oxide.

Example 3

This embodiment is a modification of the embodiment 1, and also provides a method for preparing a graphene-polyester nanocomposite fiber, which is only in the quality of the polyester polyester chip and the graphene in the preparation process of the composite masterbatch. The ratio is 100:20; the high-speed mixing method is stirred at a speed of 25,000 rpm for 0.5 min. The composite masterbatch was then mixed with pure polyester polyester chips and spun, so that the content of graphene in the final graphene-polyester nanocomposite fiber was completely consistent with that of Example 1.

Example 4

This embodiment is a modification of Embodiment 1, and is also a method for preparing a graphene-polyester nanocomposite fiber, which is only in the ratio of the mass of the polyester polyester chip to the graphene in the preparation process of the composite masterbatch. It is 100:10; the high-speed mixing method is stirred at a speed of 20,000 rpm for 2.5 min. The composite masterbatch was then mixed with pure polyester polyester chips and spun, so that the content of graphene in the final graphene-polyester nanocomposite fiber was 5 times that of Example 1.

Comparative example 1

This comparative example is the comparative example of Example 1, which is different from Example 1 in that the graphene added in the present comparative example was not modified and modified.

Comparative example 2

This comparative example is the comparative example of Example 1, which differs from Example 1 in that the graphene and polyester chips in this comparative example were not previously premixed by a high speed mixer and directly melt-composited in a twin-screw extruder.

Performance Testing

The performance of the fiber products prepared in the above examples and comparative examples was tested. The results are shown in Table 2:

Table 2

The specific embodiments of the present invention have been described above. It is to be understood that the invention is not limited to the specific embodiments described above, and various modifications and changes may be made by those skilled in the art without departing from the scope of the invention.

Claims (10)

A method for preparing a graphene-polyester nano composite fiber, comprising the steps of: preparing a graphene-polyester polyester composite masterbatch and preparing the composite masterbatch into a graphene-polyester nanocomposite fiber step. The method for preparing a graphene-polyester nanocomposite fiber according to claim 1, wherein the step of preparing the graphene-polyester polyester composite masterbatch comprises: mixing a polyester polyester chip with graphene at a high speed. Twin-screw extrusion, granulation, that is. The method for preparing a graphene-polyester nanocomposite fiber according to claim 1 or 2, wherein the graphene is selected from the group consisting of chemical vapor deposition to produce graphene, carbon dioxide supercritical expansion and exfoliation of graphene, and chemical oxidation. Exfoliated graphene oxide, coupling agent modified graphene oxide, cationic surfactant modified graphene oxide, long chain halogenated hydrocarbon modified graphene oxide, high temperature thermal expansion reduced graphene oxide, reduction by low temperature thermal expansion Graphene oxide, electrochemically stripped graphene, modified electrochemically stripped graphene, mechanically ball-milled stripped graphene, and three-roll mill mechanically stripped of one or more of graphene. The method for preparing a graphene-polyester nanocomposite fiber according to claim 2, wherein the polyester polyester chip is dried before use. The method for preparing a graphene-polyester nanocomposite fiber according to claim 2, wherein a mass ratio of the polyester polyester chip to graphene is 100: (0.1-20). The method for preparing a graphene-polyester nanocomposite fiber according to claim 2, wherein the high-speed mixing method comprises stirring at a speed of 10,000 to 25,000 rpm for 0.5 to 4 minutes. The method for preparing a graphene-polyester nanocomposite fiber according to claim 2, wherein in the twin-screw extrusion, one, two, three, four, and five zones of the twin-screw extruder The temperatures were: 265 ° C, 268 ° C, 270 ° C, 268 ° C, 265 ° C. The method for preparing a graphene-polyester nanocomposite fiber according to claim 1, wherein the step of preparing the composite masterbatch into a graphene-polyester nanocomposite fiber comprises: a graphene-polyester polyester composite mother The granules are spun, then slowly cooled, formed, oiled, drawn and wound to form a graphene-polyester nanocomposite fiber. The method for preparing a graphene-polyester nanocomposite fiber according to claim 8, wherein the step of preparing the composite masterbatch into a graphene-polyester nanocomposite fiber comprises: polymerizing the graphene-polyester The ester composite masterbatch is dried, and the dried composite masterbatch is fed into a feeding bin and passed through a screw extruder. Spinning into the spinning box, and then through the slow cooling device, side blowing cooling to form, oiling, through the first roller, the second roller, the third roller and the final winding to make graphene-polyester nanocomposite fiber. The method for preparing a graphene-polyester nanocomposite fiber according to claim 9, wherein the temperature of one, two, and three zones of the screw extruder is 280 ° C, 283 ° C, and 285 ° C, respectively; The drying treatment has a temperature of 120-140 ° C and a time of not less than 4 hours; The spinning box has a temperature of 285 ° C; The temperature of the slow cooling device is 290 ° C; The side blowing device has a temperature of 22 ° C, a humidity of 75%, and a wind speed of 0.4 m / s; The oiling oil tanker has a rotation speed of 15r/min; The temperatures of the pair of rolls 1, the pair of rolls 2, and the pair of rolls 3 were 85 ° C, 110 ° C, and 125 ° C, respectively.

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