CN111534882B - Preparation method of functionalized multi-walled carbon nanotube reinforced polyester fiber - Google Patents
Preparation method of functionalized multi-walled carbon nanotube reinforced polyester fiber Download PDFInfo
- Publication number
- CN111534882B CN111534882B CN202010442835.8A CN202010442835A CN111534882B CN 111534882 B CN111534882 B CN 111534882B CN 202010442835 A CN202010442835 A CN 202010442835A CN 111534882 B CN111534882 B CN 111534882B
- Authority
- CN
- China
- Prior art keywords
- polyester
- mwnt
- temperature
- fiber
- drafting
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
- D01F6/00—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof
- D01F6/88—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from mixtures of polycondensation products as major constituent with other polymers or low-molecular-weight compounds
- D01F6/92—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from mixtures of polycondensation products as major constituent with other polymers or low-molecular-weight compounds of polyesters
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
- D01D5/00—Formation of filaments, threads, or the like
- D01D5/08—Melt spinning methods
- D01D5/084—Heating filaments, threads or the like, leaving the spinnerettes
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
- D01D5/00—Formation of filaments, threads, or the like
- D01D5/08—Melt spinning methods
- D01D5/098—Melt spinning methods with simultaneous stretching
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
- D01F1/00—General methods for the manufacture of artificial filaments or the like
- D01F1/02—Addition of substances to the spinning solution or to the melt
- D01F1/10—Other agents for modifying properties
Abstract
The invention discloses a preparation method of an FMWNT reinforced polyester fiber, which comprises the following steps: s1, uniformly mixing the functionalized MWNT and high-viscosity PET or PEN in a high-speed mixer, and preparing into composite granules by a double-screw mixer or a double-rotor high-speed mixer; pre-crystallizing and drying the composite granules at 160-180 ℃; s2, preparing the cut granules into melt filaments through melt spinning; s3, cooling the molten strands with air at 20-90 ℃, 50-80% relative humidity and 10-20 m/min wind speed, and then winding into a bobbin to obtain the polyester/MWNT fiber; s4, storing the polyester/MWNT fibers for 20-28 h at the temperature of 25 ℃ and under the relative humidity of 65%; s5, the polyester/MWNT fiber enters an ethylene glycol, 1, 3-propylene glycol or 1, 2-propylene glycol bath at the temperature of 80-140 ℃ for primary drafting, is subjected to secondary drafting on a hot roller at the temperature of 180-200 ℃, is subjected to tertiary drafting on a hot roller at the temperature of 200-230 ℃, and is wound into a cylinder after shaping, air blowing cooling, surface residue removal and air blowing drying. The polyester fiber prepared by the method has good physical and mechanical properties, low price and easy industrialization.
Description
Technical Field
The invention relates to the field of high-performance fiber preparation, in particular to a preparation method of a functionalized multi-walled carbon nanotube reinforced polyester fiber.
Background
High-performance fibers, especially fibers with excellent physical and mechanical properties, are necessary materials for national defense and military industry, sports, industrial equipment and the like. Polyethylene terephthalate (PET), polytrimethylene terephthalate (PPT) and polyethylene naphthalate (PEN) are common raw materials for preparing industrial yarns, the high molecular weight polyester is obtained by further performing solid-phase tackifying or liquid-phase tackifying on the polyester prepared by conventional polycondensation reaction, and the high-strength industrial yarns can be prepared by indirect or direct melt spinning, so that the high-molecular weight polyester is widely applied to the fields of liquid conveying hoses, tire cords, ropes, cable sheaths, conveyor belts, inflatable tents and the like. Industrial & Engineering Chemistry Research, vol.54, 2015, p 9150, discloses that PET Industrial filaments have a tensile break strength of 8.29 cN/dtex. Although the strength of the industrial yarn is twice higher than that of the conventional fiber, and the preparation process needs to use high molecular weight polyester, the physical and mechanical properties of the industrial yarn cannot meet the use requirements of special places. The molecular chain of the polymer is easy to break when the spinning temperature is continuously increased, and the molecular weight is continuously increased, so that the entanglement density of the molecular chain is easy to increase, and high-rate drawing cannot be carried out. Ultra-high-strength fibers have been developed, or have a rigid molecular chain structure formed by conjugated double bonds, such as poly (p-phenylene terephthalamide), poly (2-hydroxy-6-naphthoic acid-p-hydroxybenzoic acid) copolymer, poly [2, 5-dihydroxy-1, 4-phenylenepyridobisimidazole ], etc., or have an ultra-high molecular weight, such as ultra-high molecular weight polyethylene fibers (UHMWPE). The intermolecular forces in the polymer having a conjugated double bond rigid molecular chain structure are large, and it is difficult to perform drawing treatment, whereas UHMWPE requires high-power drawing treatment after gel spinning to form a highly crystalline and oriented supramolecular structure.
Polyester is a cheap and widely available polymer material, and various attempts to improve the strength of polyester fibers have been made. Zengtian Zhengren et al (SEN' I GAKKAISHI, 2004, volume 60, 11, page 338)) disclose a technique for preparing ultra-high strength PET fibers by heating with a carbon dioxide laser during polyester spinning, specificallyIrradiating laser on the surface of melt trickle extruded from a single spinneret orifice with the aperture of 1.0mm, wherein the laser intensity is 0-240W/cm2The melt temperature can be increased by about 70 ℃, so that the melt trickle can be well drawn, high-orientation and high-crystallinity polyester fibers are formed, the tensile breaking strength of the polyester fibers can reach 10cN/dtex, and the PET molecular weight is reduced due to high-strength laser irradiation, so that the breaking strength of the fibers cannot be further increased. Masuda et al (International Polymer Processing, vol. XXV, 2010, No. 2, page 159)) reported that using 0.3mm diameter spinneret holes with laser heating to produce ultra-high strength polyester fibers achieved a tensile break strength of 12.1cN/dtex, a young's modulus of 1.68GPa, and an elongation at break of 9.1%.
The multi-walled carbon nanotube (MWNT) is a multi-layered sp2The one-dimensional nano carbon material formed by curling the multi-layer graphite flakes (six-membered rings) consisting of hybridized carbon atoms has the tensile breaking strength as high as 63GPa, the Young modulus as high as 950GPa and the heat conductivity coefficient of 2000-6000W/(m.K), is a nano material with excellent performance, but because the cost is high, the nano carbon material is rarely directly used as a fiber material and used as an additive modifier, and has good application prospect in the field of preparation of mixtures. However, how to achieve uniform dispersion of MWNTs in polyesters is a long-standing problem in the industry. G.x.chen et al (Polymer, volume 47 2006, page 760 4) prepared aminated MWNTs, and melt-blended aminated MWNTs with polyamide 6, spun to prepare composite fibers loaded with different aminated MWNTs, and found that when the loading of the aminated MWNTs was 0.5 wt%, the strength of the composite fibers was increased by 42% and the modulus was increased by 35%. Chinese patent application publication No. CN104357941A discloses a method for grafting a styrene-maleic anhydride copolymer on the surface of graphene and MWNT to improve the affinity between the copolymer and polyamide 6 molecular chains, then the ratio of graphene/carbon nano tubes is adjusted to play the synergistic enhancement role of one-dimensional and two-dimensional nano materials, in-situ polymerization is carried out to prepare a polyamide 6/graphene/carbon nano tube mixture, and high-strength polymer fibers are obtained through melt spinning and post-treatment.
Although the physical and mechanical properties of the polymer/MWNT fiber prepared by the prior art are obviously improved compared with those of a comparative fiber, the physical and mechanical properties of the obtained polymer/MWNT fiber cannot exceed those of PET industrial yarn due to the lack of innovation in the aspects of controlling the miscibility between the MWNT and the polymer and causing the property deterioration due to the reduction of the molecular weight of the polymer.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a method for industrially preparing the functional multi-walled carbon nanotube (FMWNT) reinforced polyester fiber, and the prepared fiber has good physical and mechanical properties.
Therefore, the technical scheme of the invention is as follows:
a preparation method of FMWNT reinforced polyester fiber comprises the following steps:
s1, uniformly mixing 0.05-2 parts by mass of functionalized MWNT and 98-99.5 parts by mass of high-viscosity PET or PEN in a high-speed mixer; then the mixture is made into composite granules by a double-screw mixing roll or a double-rotor high-speed mixing roll,
or mixing the functionalized MWNT with terephthalic acid or naphthalenedicarboxylic acid and ethylene glycol with corresponding mass, adding a catalyst and an antioxidant, esterifying for 1-4 h at 150-210 ℃, and carrying out vacuum polycondensation for 8-10 h at 270-300 ℃ to prepare composite granules;
when the intrinsic viscosity of the composite pellets is lower than 0.95dL/g, tackifying treatment is required to increase the intrinsic viscosity to 0.95-1.10 dL/g. In the invention, the tackifying method comprises the following steps: and (3) tackifying the cut pellets in a rotary drum at 180-200 ℃ and 1.5-10 Pa for 8-12 h.
Pre-crystallizing and drying the composite granules at 160-180 ℃ for 10-20 min;
wherein the functionalized MWNT are hydroxylated, aminated or carboxylated MWNTs with the diameter of 30-50 nm, the length of 0.5-2.0 mu m and the water content of less than 60ppm, and the ratio of the number of functionalized carbon atoms is 2-5% of the total number of carbon atoms on the surface of the multi-walled carbon nano-tube.
And S2, carrying out melt spinning on the cut pellets obtained in the step S1 to prepare melt filaments, wherein the aperture of a spinneret orifice of melt spinning equipment is 0.15-0.25 mm, and the length-diameter ratio is 3: 1. The spinneret plate with small diameter is favorable for preparing the fiber with excellent physical and mechanical properties.
S3, cooling the molten filaments by air with the relative humidity of 50-80% and the wind speed of 10-20 m/min at the temperature of 20-90 ℃, and then winding into a cylinder to obtain the polyester/MWNT fiber. In the invention, the temperature of the spinning channel is set to be 20-90 ℃, and the aim of increasing the temperature of the channel is to slow down the solidification rate of the molten trickle so as to improve the drawing multiplying power. The heterogeneous nucleation of MWNT is helpful to increase the solidification rate of molten trickle, and the adoption of the same channel temperature as that in the conventional polyester spinning is not favorable for preparing the ultrahigh-strength polyester fiber.
S4, storing the polyester/MWNT fiber for 20-28 h at 25 ℃ under the environment with the relative humidity of 65%.
S5, in order to improve heating uniformity and drafting multiple, polyester/MWNT fibers firstly enter an ethylene glycol, 1, 3-propylene glycol or 1, 2-propylene glycol bath at 80-140 ℃ for primary drafting by 2.0-3.0 times, then are subjected to secondary drafting on a hot roller at 180-200 ℃ by 1.5-2.0 times, then are subjected to tertiary drafting on a hot roller at 200-230 ℃ by 1.5-2.0 times, finally are sized on a hot roller at 210-230 ℃, are subjected to room temperature air blowing and cooling, then are respectively washed in a deionized water bath and an oil solution bath containing a detergent at room temperature to remove residual ethylene glycol, 1, 3-propylene glycol or 1, 2-propylene glycol and an oiling agent, are subjected to air blowing and drying again and then are wound into a barrel, and the winding speed is 200-400 m/min. The ethylene glycol, the 1, 3-propylene glycol or the 1, 2-propylene glycol bath is used between the first drafting rollers, so that the fiber bundle is heated, the polyester can be infiltrated and plasticized, and the drafting multiple is improved.
Preferably, before the step S2, the intrinsic viscosity of the pellets is measured, and whether solid-phase tackifying is performed is determined according to whether the intrinsic viscosity of the pellet mixture in phenol/1, 1,2, 2-tetrachloroethane (mass ratio 3:2) is greater than 0.95dL/g, that is, when the intrinsic viscosity is 0.95 to 1.10dL/g, tackifying is not necessary; when the intrinsic viscosity is less than 0.95dL/g, it is indicated that the molecular chain length of the polyester is low and solid-phase thickening in a vacuum state is required. The tackifying method comprises the step of tackifying the cut pellets in a rotary drum at 180-200 ℃ and 1.5-10 Pa for 8-12 h.
Preferably, in the melt spinning in step S2, the temperatures of the screw zone IV, the bend and the pump base are 180-200, 190-250, 240-270, 270-310 and 270-310 ℃.
Preferably, in step S3, the winding speed is 2000 to 5000 m/min. The high winding speed is beneficial to improving the productivity and the orientation degree of the polyester molecular chain.
Preferably, in the step S1, the temperatures of the screw four regions and the die head of the double-screw mixing roll or the double-rotor high-speed mixing roll are 180-200, 190-250, 240-270, 270-280 and 270-280 respectively, and the extrusion rate is 10-30 kg/h.
Preferably, in step S5, the total draft ratio of the tertiary draft is controlled to be 5.0 to 7.5 times.
The intrinsic viscosity of the high-viscosity PET or PEN is 0.95-1.10 dL/g, and the preferable intrinsic viscosity is 1.05-1.10 dL/g.
The core of the invention is that 0.05-2 wt% of hydroxyl, amino or carboxylated MWNT dry powder with the diameter of 30-50 nm and the length of 0.5-2.0 mu mMWNT is added in the polyester granulating or polyester polymerizing process, the one-dimensional nano material containing functional groups is uniformly dispersed in polyester resin, can weaken pi-pi conjugate acting force between benzene rings or naphthalene rings on polyester molecular chains, form hydrogen bonds with carbonyl, reduce acting force and entanglement density between polyester molecular chains, induce the polyester molecular chains to form regular crystal structures on the surfaces of the polyester molecular chains, improve the crystallinity of fibers, and transfer the high physical and mechanical properties of the fibers into a polyester matrix, obtain the composite fibers with the tensile breaking strength of 12cN/dtex and the Young modulus of 250cN/dtex or more without the help of special heating means, and easily realize industrialization. Meanwhile, the speed of transferring heat from the screw sleeve to the polyester molecular chain in the processing process is improved, the time for realizing the crystal nucleus-free melting is reduced, and the stability in the melting and conveying process is improved.
The functionalized MWNT with the mass fraction of less than 0.05 percent is difficult to play a role in modification, and the mass fraction of more than 2 percent is easy to cause uneven dispersion and difficult spinning, so that the tensile strength and Young modulus of the fiber can not meet the requirements.
The functionalized MWNT have the diameter of 30-50 nm, are too small in diameter, too large in flexibility and large in length-diameter ratio, and are easy to form entanglement in polyester resin, so that the dispersion is difficult; too large diameter and too high rigidity, the uniformity of dispersion in the polyester is limited, and at the same time, the MWNT number becomes small, and the heterogeneous nucleation efficacy is lowered.
The length of the functionalized MWNT is 0.5-2.0 mu m, the length is too small, and the functionalized MWNT is easy to uniformly disperse in polyester resin, but has low van der Waals force with a polyester molecular chain and is not easy to play a role in reinforcement; too large a length and a large aspect ratio tend to form entanglement, making dispersion difficult and failing to exert a reinforcing effect.
The functionalized MWNTs are preferably MWNTs containing hydroxyl, amino or carboxyl functional groups capable of forming hydrogen bonds with a carbonyl group, O-H…O has a bond strength of 21kJ/mol, N-H…The bonding strength of O is 8kJ/mol, the interaction force among polyester molecular chains is further weakened, the thermal stability time and the processability of the polyester are favorably improved, and the physical and mechanical properties of the fiber are favorably improved by the hydrogen bonding effect after the fiber is formed.
The enhancement function is that the one-dimensional nano structure of MWNT is oriented along the axial direction of the fiber in the drafting process after the mixture melt is extruded from the spinneret orifice and distributed in the fiber to induce the polyester molecular chain to form regularly growing polymer string crystals on the surface of the fiber, so that the crystallinity and the crystallization regularity of the fiber are improved, when the fiber is subjected to external force to generate molecular chain sliding, the regular string crystals limit the sliding of the molecular chain, the stress is transferred to a wider range, and the mechanical locking force realizes the purpose of greatly improving the tensile breaking strength of the composite fiber.
The invention adopts functional MWNT with specific diameter and length as a reinforcement, realizes the regulation and control of pi-pi conjugation and hydrogen bonding between benzene rings or naphthalene rings in a polyester molecular chain by changing the diameter, the length, the type of functional groups, the addition amount and the like of the MWNT, further performs solid-phase tackifying on the polymer/MWNT, and improves the crystallinity and the orientation degree of the polyester fiber by adopting methods of melt spinning, oil bath heating and fractional drafting on the molded fiber, wherein the tensile strength of the prepared fiber is more than 12cN/dtex, the Young modulus is more than 200cN/dtex, and the elongation at break is 6-15%. The production process of the invention is easier to realize industrialization and has lower product price.
Detailed Description
The production process of the present invention will be described in detail with reference to specific examples.
Unless otherwise specified, the raw materials used in the following examples were dried to a water content of less than 60 ppm. Characterization of the composition, structure and properties of the polyester/MWNT fibers obtained, except where indicated, using the following equipment:
observing the surface appearances of the MWNT and the composite fiber by using a Hitachi S4800 scanning electron microscope; and a LLY-06 type electronic single fiber strength tester is adopted to test the mechanical properties of the pure polyester fiber and the composite fibers in each proportion. And (3) stretching each fiber at a constant speed, wherein the clamping distance is 10mm, the stretching speed is 10mm/min, and an average value is obtained by measuring each group of fibers 10 times. Young's modulus is the ratio of stress to strain at 1% deformation.
Example 1
A preparation method of an aminated MWNT reinforced polyester fiber comprises the following steps:
s1, 0.5 part by mass of aminated MWNT having an average diameter of 50nm and a length of 0.5 μm (the number of aminated carbon atoms is 2% of the number of carbon atoms on the surface of the MWNT), and 99.5 parts by mass of PEN pellets having an intrinsic viscosity of 1.08dL/g were mixed, and then treated at 1800rpm for 20min in a high-speed mixer, left to stand for 30min and then taken out. Then the mixture is added into a twin-screw extruder with the diameter of 25mm for melt extrusion once, the temperature of the four zones of the extruder and the temperature of a die head are respectively 200, 250, 270, 280 and 280 ℃, and the intrinsic viscosity of the obtained granules is 0.96 dL/g. The pellets are pre-crystallized at 170 ℃ and dried for 20min before being directly used for melt spinning.
S2, melt spinning: wherein the temperatures of the first zone to the fourth zone of the screw, the bent pipe and the pump seat of the single-screw extruder are respectively 200, 250, 270, 300 and 300 ℃; the diameter of the spinneret orifice of the melt spinning equipment is 0.20mm, the length-diameter ratio is 3:1, and the number of the orifices is 96.
S3, cooling the strand silk by an air channel with 90 ℃, 65% relative humidity and 20m/min wind speed, and then winding into a tube with the winding speed of 4000 m/min.
S4, storing the polyester/aminated MWNT fiber obtained in the step S3 at 25 ℃ under an environment with a relative humidity of 65% for 24 h.
S5, the polyester/aminated MWNT fiber obtained in the step S4 firstly enters a 1, 3-propylene glycol bath at 140 ℃ for primary drafting by 2.5 times, then is subjected to secondary drafting by 2.0 times on a hot roller at 200 ℃, is subjected to tertiary drafting by 1.5 times and total drafting by 7.5 times on a hot roller at 230 ℃, is finally shaped on the hot roller at 230 ℃, is cooled by air blowing at room temperature, then is washed in a deionized water bath and an oil bath containing a detergent at room temperature respectively to remove 1, 3-propylene glycol and an oiling agent on the surface, is wound into a cylinder after air blowing and drying again, and the winding speed is 350m/min, thus obtaining a finished product.
Through the observation of the fiber section, no agglomeration of MWNT is seen, and the tensile breaking strength of the composite fiber is 15cN/dtex, the Young modulus is 300cN/dtex, and the elongation at break is 8 percent.
Example 2
A method for preparing a carboxylated MWNT reinforced polyester fiber, comprising the steps of:
s1, mixing carboxylated MWNT (the number of carboxylated carbon atoms accounts for 5% of the number of carbon atoms on the surface of the MWNT) with the average diameter of 40nm and the length of 1.5 μm, 2, 6-naphthalene dicarboxylic acid (NDC) and ethylene glycol in a stainless steel reaction kettle, wherein the molar ratio of the ethylene glycol to the NDC is 2.8: 1; adding n-butyl titanate as catalyst in the amount of 8x10 of NDC-4mol, taking hindered phenol 1010 as an antioxidant, and taking the dosage of 1x10 of NDC-4And mol, purging the reaction kettle for 3 times by nitrogen, wherein the esterification reaction temperature is 210 ℃, gradually raising the temperature of the reaction kettle to 295 ℃ after 4 hours, reducing the pressure to 1.8Pa, extruding into strips after 6 hours, cooling, and granulating, wherein the inherent viscosity of the granules is 1.06 dL/g. The mass fraction of the carboxylated MWNT is 0.5 percent as determined by a dissolution, filtration and weighing method. The pellets are pre-crystallized at 190 ℃ and dried for 10min and then directly used for melt spinning.
S2, drying, cutting into granules, adding into a single screw extruder with the diameter of 25mm, setting the temperatures of a first area, a second area, a third area and a bent pipe of the screw to be 180, 220, 250, 280, 310 and 310 ℃ respectively, setting the temperature of a pump base to be 310 ℃, setting the diameter of a spinneret orifice of the melt spinning equipment to be 0.25mm, and setting the length-diameter ratio to be 3: 1.
S3, cooling the obtained strand silk by an air channel with the temperature of 20 ℃, the relative humidity of 65 percent and the wind speed of 12m/min, and then winding at the speed of 5000 m/min.
S4, storing the polyester/carboxylated MWNT fiber obtained in the step S3 for 24 hours at the temperature of 25 ℃ and the relative humidity of 65%.
S5, the fiber obtained in the step S4 is firstly put into a 1, 3-propylene glycol bath at 110 ℃ for primary drafting by 2.5 times, then is subjected to secondary drafting by 2.0 times on a hot roller at 200 ℃, is subjected to tertiary drafting by 1.5 times and total drafting multiple by 7.5 times on a hot roller at 230 ℃, is finally shaped on the hot roller at 230 ℃, is subjected to air blowing and cooling at room temperature, is washed in a deionized water bath and an oil bath respectively at room temperature to remove 1, 3-propylene glycol on the surface and oil, is subjected to air blowing and drying again and is wound into a barrel, and the winding speed is 280m/min, so that a finished product is obtained.
Through the observation of the fiber section, no agglomeration of MWNT is found, and the tensile breaking strength of the composite fiber is measured to be 13.2cN/dtex, the Young modulus is 225cN/dtex, and the breaking elongation is 12%.
Example 3
A method of making a hydroxylated MWNT reinforced polyester fiber comprising the steps of:
s1, 1.0 part by mass of hydroxylated MWNT (the number of hydroxylated carbon atoms accounts for 3% of the number of carbon atoms on the surface of the MWNT) having an average diameter of 30nm and a length of 1.0 μm was taken, mixed with 99.0 parts by mass of PET pellets (intrinsic viscosity 1.05dL/g), treated at 2000rpm for 10min in a high-speed mixer, allowed to stand for 20min, and then taken out. And adding the mixture into a double-rotor high-speed mixing extruder with the diameter of 25mm, carrying out melt extrusion once, wherein the temperatures of four zones of the extruder and a die head are respectively 200, 250, 265, 270 and 270 ℃, and the intrinsic viscosity of the obtained granules is 0.86 dL/g. The pellets are tackified in a rotary drum at 200 ℃ and 1.5Pa for 8h to ensure that the intrinsic viscosity reaches 1.10dL/g, and then the pellets are pre-crystallized at 180 ℃ and dried for 20min to be used for melt spinning.
S2, melt spinning: wherein, the temperatures of the first zone to the fourth zone of the screw, the bent pipe and the pump seat of the single screw extruder are respectively 200, 250, 270, 295 and 295 ℃; the diameter of the spinneret orifice of the melt spinning equipment is 0.18mm, the length-diameter ratio is 3:1, and the number of the orifices is 96.
S3, cooling the strand silk by an air channel with 70 ℃, 65% relative humidity and 16m/min wind speed, and winding into a tube with the winding speed of 3500 m/min.
S4, storing the polyester/hydroxylated MWNT fiber obtained in the step S3 for 22h in an environment with a temperature of 25 ℃ and a relative humidity of 65%.
S5, the polyester/hydroxylated MWNT fiber obtained in the step S4 firstly enters a 1, 3-propylene glycol bath at 100 ℃ to be subjected to primary drafting by 3 times, then is subjected to secondary drafting by 1.5 times on a hot roller at 200 ℃, and then is subjected to tertiary drafting by 1.5 times on a hot roller at 220 ℃, wherein the total drafting multiple is 6.75 times, finally, the fiber is shaped on the hot roller at 220 ℃, is subjected to air blowing and cooling at room temperature, then is washed in a deionized water bath and an oil bath containing a detergent at room temperature to remove surface oil stains and oil, is subjected to air blowing and drying again to be wound into a cylinder, and the winding speed is 300 m/min.
The fiber section observation shows that no MWNT agglomeration occurs, and the tensile breaking strength of the composite fiber is measured to be 12.5cN/dtex, the Young modulus is 210cN/dtex, and the breaking elongation is 13%.
Example 4
A method of making a hydroxylated MWNT reinforced polyester fiber comprising the steps of:
s1, mixing hydroxylated MWNT (the number of hydroxylated carbon atoms accounts for 5% of the number of carbon atoms on the surface of MWNT) with average diameter of 40nm and length of 1.2 μm, 1, 4-terephthalic acid (PTA) and ethylene glycol in a stainless steel reaction kettle at a molar ratio of ethylene glycol to PTA of 2.6, adding zinc acetate as catalyst in an amount of 4x10 of PTA-4mol; hindered phenol 1010 as antioxidant in the amount of 1x10 of PTA-4And (2) purging the reaction kettle for 3 times by nitrogen, performing esterification reaction at 200 ℃, gradually raising the temperature of the reaction kettle to 295 ℃ after 4 hours, controlling the pressure to be 1.5Pa, extruding into strips after 5 hours, cooling and granulating, wherein the intrinsic viscosity is 1.05dL/g, and the mass fraction of the hydroxylated MWNT is 2.0% as determined by a dissolving, filtering and weighing method. And granulating, pre-crystallizing at 180 ℃, drying for 15min, and directly using for melt spinning.
S2, melt spinning: wherein, the temperatures of the first zone to the fourth zone of the screw, the bent pipe and the pump seat of the single screw extruder are respectively 200, 250, 270, 295 and 295 ℃; the diameter of a spinneret orifice of the melt spinning equipment is 0.25mm, the length-diameter ratio is 3:1, and the number of the holes is 192.
S3, cooling the strand silk through an air channel with the temperature of 90 ℃, the relative humidity of 65% and the air speed of 16m/min, and then winding into a bobbin with the winding speed of 5000 m/min.
S4, storing the fiber obtained in the step S3 for 26h in an environment with the temperature of 25 ℃ and the relative humidity of 65 percent.
S5, the fiber obtained in the step S4 is firstly put into a glycol bath at 100 ℃ for primary drafting by 2.5 times, then is secondly drafted on a hot roller at 200 ℃ by 2.0 times, and is thirdly drafted on a hot roller at 230 ℃ by 1.5 times and the total draft multiple is 7.5 times, finally is shaped on a hot roller at 230 ℃, is blown and cooled by air at room temperature, and then is washed in a deionized water bath and an oil bath containing detergent at room temperature respectively to remove surface oil stains, is oiled, is blown and dried by air again and then is wound into a cylinder, and the winding speed is 350m/min, so that a finished product is obtained.
The observation of the fiber section shows that no agglomeration of the hydroxylated MWNT occurs, and the tensile breaking strength of the composite fiber is measured to be 12.1cN/dtex, the Young modulus is 223cN/dtex, and the breaking elongation is 11%.
Example 5
1.0 part by mass of a hydroxylated MWNT having an average diameter of 50nm and a length of 1.5 μm (the number of hydroxylated carbon atoms accounts for 3% of the number of carbon atoms on the surface of the MWNT) was mixed with 99.0 parts by mass of PPT pellets (intrinsic viscosity: 0.70dL/g), treated at 2000rpm in a high-speed mixer for 10min, left to stand for 20min, and then taken out. Adding the mixture into a double-rotor high-speed mixing extruder with the diameter of 25mm, carrying out melt extrusion once, wherein the temperature of a four-zone extruder and a die head are respectively 250, 270, 290 and 290 ℃, the inherent viscosity of the cut granules is 0.55dL/g, after drying, tackifying for 10h in a vacuum rotary drum under the pressure of 2Pa, and increasing the inherent viscosity to 0.96 dL/g. The process conditions of example 2 were used for pre-crystallization, drying, spinning and post-drawing to obtain the final product.
The fiber section observation shows that no MWNT agglomeration occurs, and the tensile breaking strength of the composite fiber is measured to be 12.1cN/dtex, the Young modulus is 220cN/dtex, and the elongation at break is 15%.
Example 6
A method for preparing a carboxylated MWNT reinforced polyester fiber, comprising the steps of:
s1, 1.0 part by mass of carboxylated MWNT (the number of carboxylated carbon atoms accounts for 3% of the number of carbon atoms on the surface of the MWNT) having an average diameter of 40nm and a length of 1.5 μm was taken, mixed with 99.0 parts by mass of PET pellets (intrinsic viscosity 1.05dL/g), treated at 2000rpm for 10min in a high-speed mixer, allowed to stand for 20min, and then taken out. And adding the mixture into a double-rotor high-speed mixing extruder with the diameter of 25mm, carrying out melt extrusion once, wherein the temperatures of four zones of the extruder and a die head are respectively 200, 250, 265, 270 and 270 ℃, and the intrinsic viscosity of the obtained granules is 0.82 dL/g. The pellets are tackified in a rotary drum at 180 ℃ and 10Pa for 12h to ensure that the intrinsic viscosity reaches 1.06dL/g, and then the pellets are pre-crystallized at 190 ℃ and dried for 10min to be used for melt spinning.
S2, melt spinning: wherein, the temperatures of the first zone to the fourth zone of the screw, the bent pipe and the pump seat of the single screw extruder are respectively 200, 250, 270, 295 and 295 ℃; the diameter of the spinneret orifice of the melt spinning equipment is 0.18mm, the length-diameter ratio is 3:1, and the number of the orifices is 96.
S3, cooling the strand silk by an air channel with 60 ℃, 65% relative humidity and 16m/min wind speed, and then winding into a tube with the winding speed of 4000 m/min.
S4, storing the polyester/carboxylated MWNT fiber obtained in the step S3 for 28h in an environment with a temperature of 25 ℃ and a relative humidity of 65%.
S5, the polyester/carboxylated MWNT fiber obtained in the step S4 firstly enters a 1, 3-propylene glycol bath at 100 ℃ for primary drafting by 3 times, then undergoes secondary drafting by 1.5 times on a hot roller at 200 ℃, then undergoes tertiary drafting by 1.5 times on a hot roller at 220 ℃, the total drafting multiple is 6.75 times, finally the fiber is shaped on the hot roller at 220 ℃, is cooled by air blowing at room temperature, and then is washed in a deionized water bath and an oil bath containing detergent at room temperature to remove surface oil stains, oil solution is applied, and is wound into a cylinder after air blowing and drying again, and the winding speed is 300 m/min.
The fiber section observation shows that no FMWNT agglomeration occurs, and the tensile breaking strength of the composite fiber is measured to be 12.1cN/dtex, the Young modulus is 202cN/dtex, and the elongation at break is 14%.
Comparative example 1
A preparation method of MWNT reinforced PET fiber comprises the following steps:
the same composition, process and process parameters as in example 1 were used to prepare a PEN/MWNT fiber by using 0.5 part by mass of MWNT having an average diameter of 50nm and a length of 0.5. mu.m, instead of 0.5 part by mass of aminated MWNT having an average diameter of 50nm and a length of 0.5. mu.m in example 1 (the number of aminated carbon atoms is 2% of the total number of carbon atoms).
Through observation of the fiber section, MWNT are partially agglomerated, and the tensile breaking strength of the composite fiber is 6.2cN/dtex, the Young modulus is 180cN/dtex, and the elongation at break is 14%.
Comparative example 2
A process for preparing carboxylated MWNT reinforced PEN fibers, comprising the steps of:
the raw material composition, the process and the process parameters which are the same as those of the example 2 are adopted, and the difference is that the obtained strand silk is cooled by an air channel with the temperature of 18 ℃, the relative humidity of 65 percent and the air speed of 16m/min and then is wound at the speed of 5000 m/min.
The spinning process has more broken filaments, which causes frequent stop. Through observation of the fiber section, MWNT are partially agglomerated, and the tensile breaking strength of the composite fiber is 5.8cN/dtex, the Young modulus is 190cN/dtex, and the elongation at break is 23%.
From the test results of the two comparative examples, it can be seen that ultra-high strength fibers cannot be prepared by using the conventional MWNT and the conventional spinning shaft process parameters.
Claims (10)
1. A preparation method of a functionalized multi-walled carbon nanotube reinforced polyester fiber comprises the following steps:
s1, uniformly mixing 0.05-2 parts by mass of functionalized multi-walled carbon nanotubes and 98-99.5 parts by mass of high-viscosity PET or PEN in a high-speed mixer; then the mixture is made into composite granules by a double-screw mixing roll or a double-rotor high-speed mixing roll,
or mixing the functionalized multi-walled carbon nanotubes with terephthalic acid or naphthalenedicarboxylic acid and ethylene glycol of corresponding mass, adding a catalyst and an antioxidant, esterifying for 1-4 h at 150-210 ℃, and carrying out vacuum polycondensation for 8-10 h at 270-300 ℃ to prepare composite granules;
pre-crystallizing and drying the composite granules at 170-190 ℃ for 10-20 min;
wherein the functionalized multi-wall carbon nano tube is hydroxylated, aminated or carboxylated multi-wall carbon nano tube dry powder with the diameter of 30-50 nm, the length of 0.5-2.0 mu m and the water content of less than 60ppm, and the number of functionalized carbon atoms accounts for 2-5% of the total number of carbon atoms on the surface of the multi-wall carbon nano tube;
s2, carrying out melt spinning on the cut pellets obtained in the step S1 to prepare melt filaments, wherein the aperture of a spinneret orifice of melt spinning equipment is 0.15-0.25 mm, and the length-diameter ratio is 3: 1;
s3, cooling the molten filaments by air with the temperature of 20-90 ℃, relative humidity of 50-80% and wind speed of 10-20 m/min, and then winding into a cylinder to obtain the polyester/multi-walled carbon nanotube fiber;
s4, storing the polyester/multi-walled carbon nanotube fiber for 20-28 h at the temperature of 25 ℃ and the relative humidity of 65%;
s5, firstly, allowing polyester/multi-walled carbon nanotube fibers to enter an ethylene glycol, 1, 3-propylene glycol or 1, 2-propylene glycol bath at the temperature of 80-140 ℃ for primary drafting by 2.0-3.0 times, then performing secondary drafting on a hot roller at the temperature of 180-200 ℃ by 1.5-2.0 times, then performing tertiary drafting on a hot roller at the temperature of 200-230 ℃ by 1.5-2.0 times, finally shaping on a hot roller at the temperature of 210-230 ℃, cooling by room-temperature air blowing, washing in a deionized water bath and an oil solution bath containing a detergent at room temperature respectively, removing residual ethylene glycol, 1, 3-propylene glycol or 1, 2-propylene glycol, applying an oil solution, drying by air blowing again, and then winding into a drum, wherein the winding speed is 200-400 m/min.
2. The method of claim 1, wherein: in step S1, the intrinsic viscosity of the composite pellets is measured before pre-crystallization and drying, and when the intrinsic viscosity is less than 0.95dL/g, the pellets are tackified to an intrinsic viscosity of 0.95 to 1.10 dL/g.
3. The method of claim 2, wherein the method of viscosifying is: and (3) tackifying the cut pellets in a rotary drum at 180-200 ℃ and 1.5-10 Pa for 8-12 h.
4. The method of claim 1, wherein: in the step S2, when melt spinning is performed, the temperatures of the screw four zones, the bent pipe and the pump base are respectively 180-200 ℃, 190-250 ℃, 240-270, 270-310 ℃ and 270-310 ℃.
5. The method of claim 1, wherein: in step S3, the winding speed is 2000-5000 m/min.
6. The method of claim 1, wherein: in the step S1, the temperatures of the screw four regions and the die head of the double-screw mixing roll or the double-rotor high-speed mixing roll are respectively 180-200 ℃, 190-250 ℃, 240-270, 270-280 and 270-280 ℃, and the extrusion rate is 10-30 kg/h.
7. The method of claim 1, wherein: in step S5, the total draft multiple of the tertiary draft is 5.0 to 7.5 times.
8. The method of claim 1, wherein: the intrinsic viscosity of the high-viscosity PET or PEN is 1.05-1.10 dL/g.
9. The method of claim 1, wherein: in step S5, the winding speed is 220-350 m/min.
10. A functionalized multi-walled carbon nanotube reinforced polyester fiber is characterized in that: prepared by the process of any one of claims 1-9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010442835.8A CN111534882B (en) | 2020-05-22 | 2020-05-22 | Preparation method of functionalized multi-walled carbon nanotube reinforced polyester fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010442835.8A CN111534882B (en) | 2020-05-22 | 2020-05-22 | Preparation method of functionalized multi-walled carbon nanotube reinforced polyester fiber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111534882A CN111534882A (en) | 2020-08-14 |
| CN111534882B true CN111534882B (en) | 2022-05-20 |
Family
ID=71972823
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010442835.8A Active CN111534882B (en) | 2020-05-22 | 2020-05-22 | Preparation method of functionalized multi-walled carbon nanotube reinforced polyester fiber |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111534882B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112301552B (en) * | 2020-10-29 | 2022-09-27 | 东华大学 | Polyolefin/polyester bicomponent fiber and preparation method of spun-bonded non-woven fabric thereof |
| CN112941645A (en) * | 2021-01-27 | 2021-06-11 | 嘉兴市博胜新材料股份有限公司 | Antistatic polyester yarn processing technology |
| CN114921860B (en) * | 2022-06-27 | 2023-04-28 | 浙江鼎艺新材料科技有限公司 | Fine denier chinlon 6DTY and production method thereof |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20090098350A (en) * | 2008-03-14 | 2009-09-17 | 금오공과대학교 산학협력단 | Pla/mwnt-g-pla including mwnt-g-pla and method for preparing the same |
| CN102899742A (en) * | 2012-11-07 | 2013-01-30 | 东华大学 | Electrically conductive composite fiber containing carbon nanotubes and preparation method of fiber |
| CN103102683A (en) * | 2013-02-17 | 2013-05-15 | 太原理工大学 | Preparation method of carbon nanotube/polyamide 66 composite material |
| CN103709741A (en) * | 2013-12-30 | 2014-04-09 | 深圳市三顺中科新材料有限公司 | CNT (Carbon Nano Tube)/nylon6 composite material and preparation method thereof |
| CN104357941A (en) * | 2014-11-04 | 2015-02-18 | 天津工业大学 | Graphene and multiwalled carbon nanotube synergetic enhanced polymer fiber and preparation method thereof |
| CN104357953A (en) * | 2014-11-17 | 2015-02-18 | 太原理工大学 | Preparation method of tough polylactic acid composite fiber |
| CN104975368A (en) * | 2015-07-27 | 2015-10-14 | 天津工业大学 | Multiwalled carbon nanotube and graphene reinforced modified regenerated protein fiber and preparation method thereof |
| CN107400232A (en) * | 2017-06-26 | 2017-11-28 | 杭州师范大学 | A kind of copolyesteramide of carbon nano-tube modification and its preparation method of fiber and application |
-
2020
- 2020-05-22 CN CN202010442835.8A patent/CN111534882B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20090098350A (en) * | 2008-03-14 | 2009-09-17 | 금오공과대학교 산학협력단 | Pla/mwnt-g-pla including mwnt-g-pla and method for preparing the same |
| CN102899742A (en) * | 2012-11-07 | 2013-01-30 | 东华大学 | Electrically conductive composite fiber containing carbon nanotubes and preparation method of fiber |
| CN103102683A (en) * | 2013-02-17 | 2013-05-15 | 太原理工大学 | Preparation method of carbon nanotube/polyamide 66 composite material |
| CN103709741A (en) * | 2013-12-30 | 2014-04-09 | 深圳市三顺中科新材料有限公司 | CNT (Carbon Nano Tube)/nylon6 composite material and preparation method thereof |
| CN104357941A (en) * | 2014-11-04 | 2015-02-18 | 天津工业大学 | Graphene and multiwalled carbon nanotube synergetic enhanced polymer fiber and preparation method thereof |
| CN104357953A (en) * | 2014-11-17 | 2015-02-18 | 太原理工大学 | Preparation method of tough polylactic acid composite fiber |
| CN104975368A (en) * | 2015-07-27 | 2015-10-14 | 天津工业大学 | Multiwalled carbon nanotube and graphene reinforced modified regenerated protein fiber and preparation method thereof |
| CN107400232A (en) * | 2017-06-26 | 2017-11-28 | 杭州师范大学 | A kind of copolyesteramide of carbon nano-tube modification and its preparation method of fiber and application |
Non-Patent Citations (2)
| Title |
|---|
| Structure and Properties of MWNTs-OH/PET FDY Composite Fiber;Wensheng Hou等;《Advanced Materials Research》;20110902(第332-334期);全文 * |
| Synthesis and Properties of Poly(ethylene 2,6-naphthalate)/MWNT Nanocomposites Prepared by in situ Polymerization(I)−Synthesis and Characterization−;Min Ho Jee等;《Textile Science and Engineering》;20081231;第45卷(第1期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111534882A (en) | 2020-08-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111534882B (en) | Preparation method of functionalized multi-walled carbon nanotube reinforced polyester fiber | |
| RU2746113C1 (en) | Graphene composite material and method of production thereof | |
| KR20190049614A (en) | Isotropic " ready-to-use " plastic pellets with highly entangled nanofibrils and their production methods | |
| KR101775142B1 (en) | A polyethylene multifilament fiber with high tenacity and its manufacturing process | |
| CN105862152A (en) | Production method for high-speed spinning low-stretching high-modulus low-shrinkage polyester industrial filaments | |
| CN113278268B (en) | High-toughness polyester composite material and preparation method thereof | |
| CN102277646B (en) | Method for manufacturing polyester industrial yarns with high size, high stability, high modulus and low shrink | |
| JP7059446B2 (en) | High modulus, low shrinkage, activated polyester industrial yarn and its manufacturing method | |
| CN101824664B (en) | Method for preparing high-strength polyester industrial yarns | |
| CN111411417A (en) | Graphene reinforced polyketone fiber and preparation method thereof | |
| CN110184678B (en) | Preparation method of graphene and liquid crystal polyester synergetic enhanced polymer fiber | |
| JP4617872B2 (en) | Polylactic acid fiber | |
| KR100602286B1 (en) | Polyester fiber and preparation thereof | |
| CN114232127B (en) | Ultralow-thermal-shrinkage polyester staple fiber and preparation method thereof | |
| CN115467045A (en) | Full-bio-based degradable composite elastic fiber and preparation method thereof | |
| KR20190088652A (en) | Manufacturing method of polyester filament with high-strength containing carbon black master batch | |
| JP2004100087A (en) | Recycled polyester fiber | |
| CN107326474B (en) | Graphene and polyester composite fiber for cord and preparation method thereof | |
| CN114015214B (en) | Polylactic acid/degradable polyester elastomer blend and preparation method thereof | |
| KR101772586B1 (en) | A polypropylene fiber with high tenacity and low shrinkage and its manufacturing process | |
| CN109750363B (en) | Preparation method of ultralow-shrinkage polyester industrial yarn | |
| US20210253824A1 (en) | Conductive polymeric composition and fiber yarn | |
| CN116288773A (en) | Special material for random copolymer polypropylene soft fiber and preparation method thereof | |
| JPH086205B2 (en) | Molecularly oriented molded product of ultra-high molecular weight ethylene / propylene copolymer | |
| JPS6149408B2 (en) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |