CN115928251A - A kind of preparation method of in-situ graphene modified PET fiber - Google Patents

Abstract

The invention relates to the technical field of graphene fiber preparation, and discloses a preparation method of in-situ graphene modified PET fibers, which comprises the following steps: (1) Adding a graphene material in the polymerization process of PET polyester to obtain a graphene modified PET raw material; (2) Carrying out melt spinning on the graphene modified PET raw material, and adding a PBT high polymer on line in the melting process to obtain the graphene modified PET fiber. In the preparation process of the PET, the graphene material is added in an in-situ polymerization manner, and due to the structural particularity, the PET fibers can be endowed with the functions of antibiosis, mite prevention, warm keeping, ultraviolet resistance and the like; in the fiber preparation process, the polybutylene terephthalate is added in a melting way in a master batch adding way, so that the spinnability of the fiber preparation and the strength of the fiber finished product can be improved.

Description

A kind of preparation method of in-situ graphene modified PET fiber

technical field

The invention relates to the technical field of preparing graphene fibers, in particular to a method for preparing in-situ graphene-modified PET fibers.

Background technique

Single-layer carbon graphene or single-layer annular boron nitride (white graphene) material has photoelectric effect due to its special structure, and the graphene fiber spun from it also has antibacterial, anti-mite, warm and anti-bacterial properties. UV and other functionalities have attracted great attention from the industry. However, mixing graphene into fiber polymers by online addition of masterbatches will easily cause graphene to agglomerate, destroy the layered structure, and distribute unevenly, resulting in a decrease in the functionality of the prepared fiber. At the same time, after the addition of graphene, the polymer fiber material is easy to become brittle, and it is easy to break during the preparation and use process, or the monofilament breaks to form quality problems such as hairs and hairballs, the production efficiency is low, and the use performance is poor. The bottleneck problem restricting the application and development of graphene in the fiber field.

The Chinese invention patent with publication number CN112301454A discloses a preparation method of PET-based graphene conductive fiber, including: 1) providing graphene/PET functional masterbatch and PET natural color chips, said graphene/PET functional masterbatch and PET The moisture content of natural color slice is lower than 30ppm; 2) described graphene/PET functional masterbatch and PET natural color slice are fed into twin-screw extruder after melting and blending by dynamic mixer, obtain PET-based graphene nascent fiber, so The dynamic mixer is a three-dimensional high-efficiency dynamic mixer; 3) PET-based graphene nascent fibers are drawn and heat-set to obtain PET-based graphene conductive fibers. However, the graphene fiber obtained by the melt blending of graphene/PET functional masterbatch and PET natural color chip has not improved the problem of easy embrittlement and end breakage of graphene in the fiber material, and the performance of the fiber has not been improved. poor.

Contents of the invention

In order to solve the above-mentioned technical problems, the present invention provides a method for preparing in-situ graphene-modified PET fibers. During the preparation of PET polyester, in-situ polymerization adds graphene materials, and in the fiber preparation process, the masterbatch The addition method melts and adds polybutylene terephthalate (PBT), so that the graphene-modified PET fiber has functionality while improving the strength and toughness of the fiber.

The purpose of the present invention is achieved through the following technical solutions:

The invention provides a kind of preparation method of in-situ graphene modified PET fiber, comprises the steps:

(1) Add graphene material in the polymerization process of PET polyester, obtain graphene modified PET raw material;

(2) The graphene-modified PET raw material is melt-spun, and the PBT polymer is added online during the melting process to obtain the graphene-modified PET fiber.

In the present invention, graphene material is added by in-situ polymerization in the preparation process of PET polyester. Due to the particularity of its structure, graphene with single-layer carbon structure or single-layer boron nitride (white graphene) can endow PET fiber with antibacterial and anti-mite , warmth and anti-ultraviolet functions. Moreover, in order to improve the quality problems such as brittleness and end breakage during the spinning or use of graphene fibers, polybutylene terephthalate (PBT) is added by melting and adding master batches during the fiber preparation process, The performance of this high polymer is close to that of PET, the two have good compatibility, and its rheological properties are very good, and it has good toughness. Adding an appropriate amount of PBT improves the spinnability of fiber preparation and the strength of finished fiber. If flexible macromolecules (PBT) are added to copolymerize during the polymerization process, the degree of polymerization of PET macromolecules will decrease, and the overall strength of the fiber will decrease.

Graphene-modified PET fiber can obtain higher fiber strength and quality uniformity, specifically, the increase in production efficiency and the reduction in end-breakage rate. At the same time, the production efficiency of the fiber in downstream weaving is improved, the machine downtime rate and the cloth surface defect rate decline.

Preferably, the added amount of the graphene material is 1-1.5‰ of the PET polyester mass.

Preferably, the added amount of the PBT high polymer accounts for 2-4% of the mass of the graphene-modified PET raw material.

Preferably, the graphene material is graphene or monolayer boron nitride.

Preferably, the addition of graphene material in the polymerization process of PET polyester is the addition of graphene material in the middle and late stage of polycondensation reaction in the polymerization process.

In the preparation process of PET macromolecular materials, graphene and ethylene glycol are first prepared into a solution with a mass concentration of 50%, in order to avoid affecting the degree of polymerization of the two monomers of terephthalic acid (PTA) and ethylene glycol, thereby reducing Therefore, after the first pre-condensation of polymerization, after the polycondensation reaction is basically completed, a certain proportion of single-layer carbon graphene or boron nitride lamellar ring is added in the second pre-condensation link before the final polycondensation. A functional modified material with a special photoelectric effect to ensure that the graphene single-layer carbon graphene or boron nitride sheet rings are distributed on the surface of the macromolecular chain in a mosaic form, thereby maintaining the sheet-like ring shape of the modified material structure, and make it evenly distributed, so that the multi-functionality of the prepared polymer material such as antibacterial, anti-mite, anti-ultraviolet, far-infrared warmth and antistatic properties is more prominent, and the functional uniformity and durability of the fabric Good sex.

Preferably, the tow obtained by the melt spinning is sequentially subjected to first oiling, pre-network, hot roll stretching, second oiling, network and winding forming to obtain graphene-modified PET fibers.

During the fiber preparation process, oiling is applied twice to increase the oiling rate and oiling uniformity, improve fiber toughness and strength from the fiber macromolecular microstructure, and optimize the production process from the fiber preparation process to reduce fiber damage, thereby improving The performance of the obtained fiber.

Preferably, the mass concentration of oil used in the oil nozzle during the first oiling process is 13-15%; the mass concentration of the oil agent used in the oil nozzle during the second oiling process is 8-10%.

Preferably, the total oiling rate of the first oiling process and the second oiling process is 0.7-1.1%, wherein the oiling rate of the first oiling process is 70-80% of the total oiling rate.

The main function of the first oiling is to improve the bundling of individual fibers, thereby improving the stability of the tow running. It is necessary to ensure the emulsification and permeability of the oil, so a lower oil concentration and a higher oil concentration are used. High oiling capacity. In addition, the graphene fiber prepared by adding graphene to the polymer material has poor dispersion of inorganic additives in the polymer, especially in the fiber spinning process, and the unique sheet structure of graphene affects its performance at high temperature. Compatibility in the molecule, so it is easy to produce broken ends, hairs, etc. during the preparation or use of the tow, which increases the difficulty of spinning the fiber. The first oiling device is set before the hot roller device, and after the tow is obtained by melt spinning, the first oiling treatment is carried out immediately, and the simultaneous effect of the surface oil phase and the hot roller drafting can promote graphene in the fiber. compatibility and stability, which in turn can optimize the quality of graphene fibers.

The main function of the second oiling is to improve the strength and uniformity of the oil film on the fiber surface, strengthen the protection of the fiber surface, further improve the protection performance of the fiber in the subsequent network and winding process, reduce the breakage rate, and improve the weaving process. Tensile, wear-resistant and other properties during use.

Preferably, the yarn guides used for the tow in the melt spinning process are all rotating yarn guides.

The yarn guide in the fiber process adopts a rotating yarn guide, especially the yarn guide below the first oil nozzle and the yarn guide above and below the second oil nozzle all use a rotating yarn guide, so that the fiber yarn and the guide wire The friction of the device changes from sliding friction to static friction, thereby reducing the fluctuation of the thread running and the damage to the thread.

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

(1) Add graphene material by in-situ polymerization during the preparation of PET polyester. Due to its special structure, graphene with single-layer carbon structure or single-layer boron nitride (white graphene) can endow PET fiber with antibacterial and antibacterial properties. Functions such as mites, warmth and anti-ultraviolet;

(2) In the process of fiber preparation, polybutylene terephthalate (PBT) is melted and added by adding masterbatch. The performance of this polymer is similar to that of PET, the compatibility between the two is good, and its rheology The performance is very good and has good toughness. Adding an appropriate amount of PBT can improve the spinnability of fiber preparation and the strength of finished fiber;

(3) Two times of oiling are used to improve the oiling rate and oiling uniformity, improve the fiber toughness and strength from the fiber macromolecular microstructure, and optimize the production process from the fiber preparation process to reduce the damage to the fiber, thereby improving the yield fiber performance.

Detailed ways

The technical scheme of the present invention is described below with specific embodiment, but protection scope of the present invention is not limited to this:

Example 1

The preparation method comprises the following steps:

(1) Add single-layer carbon graphene with a mass fraction of 1‰ in the preparation process of PET polymer, and first prepare single-layer carbon graphene and ethylene glycol into a solution with a mass concentration of 50%; polycondensation reaction of PET polymer The temperature is 280°C, the reaction time is 6h, the vacuum degree is -0.15Mp, and the above-mentioned solution is added in the middle and late stages of the polycondensation reaction (after 4h of the polycondensation reaction), and graphene-modified PET chips are obtained;

(2) Graphene modified PET chips are melt-spun, blending PBT high polymers by online addition in the melting process, and the addition of PBT high polymers accounts for 2.0% of the quality of graphene modified PET chips; after that The tow is obtained by melt spinning, followed by the first oiling, pre-network, hot roll stretching, second oiling, network and winding forming to obtain graphene modified PET fiber (125dtex/72f graphene modified Polyester fiber POY). Wherein, the spinning speed is 3000m/min; the mass concentration of the oil agent used in the first oiling nozzle is 13%, and the oiling rate is 0.64%, and the mass concentration of the oiling agent used in the second oiling nozzle is 8%. The oiling rate is 0.16%, and the total oiling rate is 0.8%; the yarn guides below the first oiling nozzle and the upper and lower yarn guides of the second oiling nozzle all use rotating yarn guides.

The 125dtex/72f graphene-modified polyester fiber POY is elasticized to obtain the 75D/72F graphene-modified polyester fiber DTY, which is then made into a finished knitted fabric.

Example 2

The preparation method comprises the following steps:

(1) In the PET polymer preparation process, add a single-layer cyclic boron nitride with a mass fraction of 1.5‰, and first prepare a single-layer carbon graphene and ethylene glycol into a solution with a mass concentration of 50%; the PET polymer The temperature of the polycondensation reaction is 280°C, the reaction time is 6h, and the vacuum degree is -0.15Mp, and the solution is added in the middle and late stages of the polycondensation reaction (after 4h of the polycondensation reaction) to obtain graphene-modified PET slices;

(2) Graphene-modified PET chips are melt-spun, blending PBT high polymers in the melting process by online addition, and the addition of PBT high polymers accounts for 3.0% of the quality of graphene-modified PET chips; after that The tow is obtained by melt spinning, followed by the first oiling, pre-network, hot roll stretching, second oiling, network and winding forming to obtain graphene-modified PET fibers (75D/48f graphene-modified Polyester fiber FDY). Wherein, the spinning speed is 4000m/min; the mass concentration of the oil agent used in the first oiling nozzle is 14%, and the oiling rate is 0.70%, and the mass concentration of the oiling agent used in the second oiling nozzle is 9%. The oiling rate is 0.30%, and the total oiling rate is 1.0%. The yarn guides below the first oiling nipple and the upper and lower yarn guides of the second oiling nipple all use rotating yarn guides.

75D/48f graphene modified polyester fiber FDY is made into finished knitted fabric.

Example 3

The preparation method comprises the following steps:

(1) Add single-layer carbon graphene with a mass fraction of 1.2‰ during the preparation of PET polymers, first prepare single-layer carbon graphene and ethylene glycol into a solution with a mass concentration of 50%; polycondensation reaction of PET polymers The temperature is 280°C, the reaction time is 6h, the vacuum degree is -0.15Mp, and the above-mentioned solution is added in the middle and late stages of the polycondensation reaction (after 4h of the polycondensation reaction), and graphene-modified PET chips are obtained;

(2) Graphene-modified PET chips are melt-spun, and blended with PBT high polymers by online addition in the melting process, the addition of PBT high polymers accounts for 4.0% of the quality of graphene-modified PET chips; after that The tow is obtained by melt spinning, followed by the first oiling, pre-network, hot roll stretching, second oiling, network and winding forming to obtain graphene modified PET fiber (175dtex/72f graphene modified Polyester fiber POY). Wherein, the spinning speed is 3100m/min; the mass concentration of the oil agent used in the first oiling nozzle is 15%, and the oiling rate is 0.60%, and the mass concentration of the oiling agent used in the second oiling nozzle is 10%. The oiling rate is 0.20%, and the total oiling rate is 0.8%. The yarn guides below the first oiling nozzle and the upper and lower yarn guides of the second oiling nozzle all use rotating yarn guides.

175dtex/72f graphene-modified polyester fiber POY is elasticized to obtain 100D/72F graphene-modified polyester fiber DTY, which is then made into finished knitted fabrics.

Comparative example 1

The difference from Example 3 is that only one oiling is carried out.

The preparation method comprises the following steps:

(1) Add single-layer carbon graphene with a mass fraction of 1.2‰ during the preparation of PET polymers, first prepare single-layer carbon graphene and ethylene glycol into a solution with a mass concentration of 50%; polycondensation reaction of PET polymers The temperature is 280°C, the reaction time is 6h, the vacuum degree is -0.15Mp, and the above-mentioned solution is added in the middle and late stages of the polycondensation reaction (after 4h of the polycondensation reaction), and graphene-modified PET chips are obtained;

(2) Graphene-modified PET chips are melt-spun, and blended with PBT high polymers by online addition in the melting process, the addition of PBT high polymers accounts for 4.0% of the quality of graphene-modified PET chips; after that The tow is obtained by melt spinning, and then through the first oiling, pre-network, hot roll stretching, network and winding forming, the graphene modified PET fiber (175dtex/72f graphene modified polyester fiber POY) is obtained. Among them, the spinning speed is 3100m/min; the mass concentration of the oil agent used in the first oiling nozzle is 15%, and the oiling rate is 0.80%; the lower yarn guide of the first oiling nozzle is a rotary yarn guide .

175dtex/72f graphene-modified polyester fiber POY is elasticized to obtain 100D/72F graphene-modified polyester fiber DTY, which is then made into finished knitted fabrics.

Comparative example 2

The difference from Example 3 is that the oiling rate of the first oiling is too low.

The preparation method comprises the following steps:

(1) Add single-layer carbon graphene with a mass fraction of 1.2‰ during the preparation of PET polymers, first prepare single-layer carbon graphene and ethylene glycol into a solution with a mass concentration of 50%; polycondensation reaction of PET polymers The temperature is 280°C, the reaction time is 6h, the vacuum degree is -0.15Mp, and the above-mentioned solution is added in the middle and late stages of the polycondensation reaction (after 4h of the polycondensation reaction), and graphene-modified PET chips are obtained;

(2) Graphene-modified PET chips are melt-spun, and blended with PBT high polymers by online addition in the melting process, the addition of PBT high polymers accounts for 4.0% of the quality of graphene-modified PET chips; after that The tow is obtained by melt spinning, followed by the first oiling, pre-network, hot roll stretching, second oiling, network and winding forming to obtain graphene modified PET fiber (175dtex/72f graphene modified Polyester fiber POY). Wherein, the spinning speed is 3100m/min; the mass concentration of the oil agent used in the first oiling nozzle is 15%, and the oiling rate is 0.50%, and the mass concentration of the oiling agent used in the second oiling nozzle is 10%. The oiling rate is 0.30%, and the total oiling rate is 0.80%. The lower yarn guide of the first oiling nozzle and the upper and lower yarn guides of the second oiling nozzle all use rotating yarn guides.

175dtex/72f graphene-modified polyester fiber POY is elasticized to obtain 100D/72F graphene-modified polyester fiber DTY, which is then made into finished knitted fabrics.

Comparative example 3

The difference from Example 3 is that the addition ratio of graphene is too high.

The preparation method comprises the following steps:

(1) Add single-layer carbon graphene with a mass fraction of 2.0‰ during the preparation of PET polymers, and first prepare single-layer carbon graphene and ethylene glycol into a solution with a mass concentration of 50%; the polycondensation reaction of PET polymers The temperature is 280°C, the reaction time is 6h, the vacuum degree is -0.15Mp, and the above-mentioned solution is added in the middle and late stages of the polycondensation reaction (after 4h of the polycondensation reaction), and graphene-modified PET chips are obtained;

(2) Graphene-modified PET chips are melt-spun, and blended with PBT high polymers by online addition in the melting process, the addition of PBT high polymers accounts for 4.0% of the quality of graphene-modified PET chips; after that The tow is obtained by melt spinning, followed by the first oiling, pre-network, hot roll stretching, second oiling, network and winding forming to obtain graphene modified PET fiber (175dtex/72f graphene modified Polyester fiber POY). Wherein, the spinning speed is 3100m/min; the mass concentration of the oil agent used in the first oiling nozzle is 15%, and the oiling rate is 0.60%, and the mass concentration of the oiling agent used in the second oiling nozzle is 10%. The oiling rate is 0.20%, and the total oiling rate is 0.8%. The yarn guides below the first oiling nozzle and the upper and lower yarn guides of the second oiling nozzle all use rotating yarn guides.

175dtex/72f graphene-modified polyester fiber POY is elasticized to obtain 100D/72F graphene-modified polyester fiber DTY, which is then made into finished knitted fabrics.

Comparative example 4

The difference from Example 3 is that the addition ratio of PBT is too low.

The preparation method comprises the following steps:

(1) Add single-layer carbon graphene with a mass fraction of 1.2‰ during the preparation of PET polymers, first prepare single-layer carbon graphene and ethylene glycol into a solution with a mass concentration of 50%; polycondensation reaction of PET polymers The temperature is 280°C, the reaction time is 6h, the vacuum degree is -0.15Mp, and the above-mentioned solution is added in the middle and late stages of the polycondensation reaction (after 4h of the polycondensation reaction), and graphene-modified PET chips are obtained;

(2) The graphene-modified PET chips are melt-spun, and the PBT high polymer is blended by online addition in the melting process, and the addition of the PBT high polymer accounts for 1.0% of the graphene-modified PET chip quality; after that The tow is obtained by melt spinning, followed by the first oiling, pre-network, hot roll stretching, second oiling, network and winding forming to obtain graphene modified PET fiber (175dtex/72f graphene modified Polyester fiber POY). Among them, the spinning speed is 3100 m/min; the mass concentration of the oil used in the first oiling nozzle is 15%, and the oiling rate is 0.60%, and the mass concentration of the oil used in the second oiling nozzle is 10%. The oiling rate is 0.20%, and the total oiling rate is 0.8%. The yarn guides below the first oiling nipple and the upper and lower yarn guides of the second oiling nipple all use rotating yarn guides.

175dtex/72f graphene-modified polyester fiber POY is elasticized to obtain 100D/72F graphene-modified polyester fiber DTY, which is then made into finished knitted fabrics.

Far-infrared emissivity: According to the standard of "GB/T 30127-2013 Testing and Evaluation of Far-infrared Properties of Textiles".

Ultraviolet transmittance: according to the standard of "AATCC183 Textile Anti-ultraviolet Radiation Performance Test Standard".

Antibacterial properties: According to the standard of "GB/T 20944.3-2008 Evaluation of Antibacterial Properties of Textiles Part 3 Oscillating Method".

Emissivity of negative oxygen ions: According to the standard of "GB/T 30127-2013 Testing and Evaluation of Far Infrared Properties of Textiles".

The finished knitted fabrics in Examples and Comparative Examples were subjected to performance tests, and the results are shown in Table 1.

Table 1

The fiber quality and performance of the graphene-modified PET fibers in the examples and comparative examples were tested during the preparation process and the downstream weaving process of the fibers, and the results are shown in Table 2.

Table 2

In Table 2, the calculation method of production efficiency is based on the ratio of the actual output of a machine per unit time to the theoretical output.

As shown in table 1, the present invention adds graphene material in situ polymerization in the preparation process of PET polyester, and the graphene of monolayer carbon structure or monolayer boron nitride (white graphene) can give due to the particularity of its structure. PET fiber has antibacterial, anti-mite, warm and anti-ultraviolet functions.

As shown in Table 2, Comparative Example 1 and Comparative Example 2 show that oiling rate and oiling uniformity are improved by two times of oiling, the fiber toughness and strength are improved from the fiber macromolecular microstructure, and the production is optimized from the fiber preparation process. The process can reduce the damage to the fiber, which can reduce the breakage rate and the performance of the fiber; while the oiling rate of the second oiling needs to be controlled in order to make the finished fiber strength better. Comparative example 3 and comparative example 4 show that the addition ratio of fiber preparation raw materials will affect the spinnability of the fiber and the performance of the fiber, and the fiber spun outside the scope of the present invention is prone to quality problems.

The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by the description of the present invention, or directly or indirectly used in other related technical fields, is the same. included in the scope of patent protection of the present invention.

Claims (9)

1. a kind of preparation method of in-situ graphene modified PET fiber is characterized in that, comprises the steps: (1) Add graphene material in the polymerization process of PET polyester to obtain graphene modified PET raw material; (2) The graphene-modified PET raw material is melt-spun, and PBT polymer is added online during the melting process to obtain graphene-modified PET fibers. 2. the preparation method of in-situ graphene modified PET fiber as claimed in claim 1, is characterized in that, the addition of described graphene material is to account for 1～1.5‰ of PET polyester quality. 3. the preparation method of in-situ graphene-modified PET fiber as claimed in claim 1, is characterized in that, the addition of described PBT high polymer is to account for 2～4% of graphene-modified PET raw material quality. 4. the preparation method of in-situ graphene-modified PET fiber as described in one of claim 1-3, it is characterized in that, described graphene material is graphene or monolayer boron nitride. 5. as the preparation method of the described in-situ graphene modified PET fiber of one of claim 1-3, it is characterized in that, described adding graphene material in the polycondensation process of PET polyester is the polycondensation reaction adding in polycondensation process Graphene material. 6. the preparation method of in-situ graphene-modified PET fiber as claimed in claim 1, is characterized in that, described melt spinning obtains tow and passes through first road oiling, pre-network, hot roller stretching, second successively. Road oiling, network and winding molding to obtain graphene modified PET fibers. 7. the preparation method of in-situ graphene-modified PET fiber as claimed in claim 6, is characterized in that, the mass concentration that oil nozzle uses oil agent is 13～15% when described first road oiling; When oiling, the mass concentration of the oil agent used in the nozzle is 8~10%. 8. the preparation method of in-situ graphene modified PET fiber as claimed in claim 6 or 7, is characterized in that, the total oiling rate of described first road oiling and second road oiling is 0.7～1.1%, wherein The oiling rate of the first oiling is 70~80% of the total oiling rate. 9. the preparation method of in-situ graphene-modified PET fiber as claimed in claim 1 or 6, is characterized in that, in described melt-spinning process, tow adopts yarn guide and is rotating yarn guide.