CN111663199A - A kind of preparation method of graphene modified PET blended fiber - Google Patents

Abstract

This invention relates to the field of chemical fibers. Addressing the problem of poor dispersibility in the existing graphene-modified fiber process, this invention discloses a method for preparing graphene-modified PET blended fibers, comprising the following steps: 1) modifying graphene with a cationic modifier; 2) preparing graphene-modified chips: blending modified cationic graphene, the modifier, and PET chip powder; 3) melting: melting the PET chips and the graphene-modified chips; 4) blending: spun from a composite spinneret to form blended fibers; 5) post-treatment: cooling, oiling, stretching, and winding the blended fibers. By improving the dispersibility of graphene sheets, the uniformity of graphene in the composite fiber is enhanced, resulting in high-performance graphene-modified PET composite fibers with excellent mechanical properties. A four-leaf clover-shaped composite fiber is prepared by spinning graphene masterbatch chips and PET chips using a composite spinneret.

Description

A kind of preparation method of graphene modified PET blended fiber

technical field

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

Background technique

Graphene is a new type of carbon material with excellent properties such as thermal conductivity, electrical conductivity, and good mechanical strength. It is praised as the most potential material in the 21st century by researchers at home and abroad. Because graphene has many outstanding properties, it is widely used in various fields such as chemistry, composite fibers, and catalyst supports. my country is rich in graphite reserves, and has formed a series of comprehensive industries, such as mining, processing, quality purification and so on. Nowadays, the annual output of graphite in my country has become the first in the world, which is about half of the world's total output, and the research and preparation process of graphene is also constantly developing, progressing and maturing. Therefore, the use of graphene in the modification of composite materials is a development where the trend is.

Polyester (PET) is the world's largest and most widely used synthetic fiber variety, accounting for more than 60% of the world's synthetic fiber output. PET has the advantages of high strength, excellent physical and mechanical properties, and good stability. It is a thermoplastic resin with excellent comprehensive properties. It is widely used in various fields, such as fibers, packaging, containers, plastics and so on. However, because the PET molecular chain contains a rigid group of benzene rings, the antistatic properties of PET are poor, which greatly limits the application of PET. There is static electricity on clothes, and a lot of dust will be adsorbed on the surface of clothes, causing it to stain clothes and affect the quality of products. Moreover, the electrification of the clothing will cause electric sparks between the clothing and the human body, which greatly affects the comfort of the clothing. More importantly, clothing with static electricity is easy to cause danger during processing, and even fire and explosion may occur in severe cases, affecting the personal safety of processing personnel. In order to give full play to the advantages of PET, such as low cost and high performance, it is of great significance to develop modified PET polyester fibers.

In recent years, the use of graphene and polymers to prepare functional fibers with conductive, antibacterial and far-infrared properties has become an important direction of current research. technical problems, and the resulting modified fibers have low strength.

Patent number CN201710138437.5, patent name "a graphene-tencel composite fiber and its preparation method" The invention discloses a graphene-tencel composite fiber and a preparation method thereof. Graphene solution and cellulose pulp are added with NMMO (N-methylmorpholine-N oxide) and water, mixed, dissolved, filtered, spun by dry spray wet process, and then finished by silk thread and graphene oxide finishing solution prepared. The Tencel composite fiber contains graphene and adopts the following steps: preparation of spinning solution, spinning, and yarn graphene finishing.

The disadvantage is that in the process of preparing the graphene polyurethane solution, the graphene sheets are prone to secondary agglomeration, resulting in poor dispersibility of graphene.

SUMMARY OF THE INVENTION

The present invention is to overcome the problem of poor dispersibility in the process of graphene-modified fibers in the prior art, and provides a preparation method of graphene-modified PET blended fibers. On the one hand, by improving the dispersion of graphene sheets themselves To improve the uniformity of graphene distribution in the composite fiber, to achieve the composite fiber of graphene modified PET with excellent performance, the fiber itself has good mechanical properties; on the other hand, by slicing the graphene masterbatch and PET chips are spun with a composite spinneret to obtain a graphene-modified composite fiber that integrates polyester with high elasticity, high renaturation, high oil absorption, high impact resistance, antistatic, antibacterial, and far-infrared properties. The preparation process is simple and the cost is saved.

In order to achieve the above object, the present invention adopts the following technical solutions:

A preparation method of graphene-modified PET blended fiber, comprising the following preparation steps:

1) modifying graphene with a cationic modifier;

2) Preparation of graphene modified chips: the modified cationic graphene, modifier and PET chip powder are blended, and then granulated by a twin-screw extruder to obtain graphene modified chips;

3) melting: the dried PET chips and the graphene modified chips are respectively melted by the screw extruder, and the obtained PET spinning melts and the graphene modified chips spinning melts;

4) Blending: two kinds of spinning melts are entered into the bi-component composite spinning assembly through respective corresponding pipes for spinning, and the two kinds of spinning melts are ejected from the composite spinneret to form blended fibers;

5) Post-treatment: after cooling, oiling, stretching and winding the above-mentioned blended fibers, the finished product is obtained.

In the present invention, modified graphene chips and PET chips are used as two components, and then a specially designed composite spinneret is used to prepare the modified graphene composite fibers with a four-leaf turf core structure. The modified graphene chips have good antistatic, antibacterial, far-infrared and other properties, and the PET chips maintain high elasticity, high renaturation, high oil absorption and high impact resistance; The cross-section is in the shape of a four-leaf clover, and the surface of the polyester component contains modified graphene components at even intervals, which has the characteristics of high strength and good elasticity. The modified graphene components at intervals are evenly distributed around the polyester component, making the The composite fiber has the performance advantages of the polyester component and the modified graphene component at the same time, and the preparation cost is low.

Preferably, the cationic modifier in step 1) is DMSO and/or tributylphosphine containing a long carbon chain.

The above-mentioned cationic modifier has cationic groups, and the cationic groups replace the functional groups on graphene oxide, so that the graphene has cations, and the dispersion effect between the cationic graphenes is better, and the addition of cations not only makes the graphene In addition to the good dispersibility of graphene, the subsequent spinning fibers also have good moisture absorption and perspiration effects.

Preferably, in step 2), the modifier used is one or more of cetyltrimethylammonium bromide, sodium lauryl sulfate, ethylenediamine and polyvinylpyrrolidone.

The addition of the modifier makes the mixing uniformity between the modified cationic graphene and the PET chip powder better, prevents the secondary agglomeration of the modified cationic graphene in the molten PET, and the bonding force between the two components is stronger. , the fluidity between the obtained mixed solutions is better.

Preferably, in step 2), the proportion of modified cationic graphene in the blend is 1%-5%, the proportion of PET chip powder is 98.9%-94%, and the proportion of modifier is 0.1%-1.

Preferably, the two components in the blended fiber in step 4) are of a sheath-core structure, including the PET spinning in the middle (A) and the graphene modified spinning (B) arranged at intervals around it.

Preferably, the cross-section of the blended fibers is a four-leaf clover shape.

The cross-section of the four-leaf clover fiber greatly increases the contact area between the two material components, so that the blended fiber has good mechanical properties while ensuring excellent antistatic ability, and can reduce the proportion of modified graphene in the fiber. Effectively reduce production costs.

Preferably, the intrinsic viscosity of the PET chips is 0.65±0.2dL/g, and the melting point is 240-265°C.

Preferably, when using a twin-screw extruder for melt granulation in step 3), the temperatures in the first to fifth zones of the screw are respectively 245-255°C, 260-270°C, 265-275°C, 265-275°C, 260- 270°C.

If the screw temperature is lower than this range, the molding will be poor; if the screw temperature is high, it will easily cause the degradation of the chips, which will affect the quality of the fibers in the subsequent processing.

Preferably, in step 4), the mass ratio of the graphene modified chips to the PET chips is 20:80-40:60; the screw temperature of the two-component composite spinning assembly is 280-310° C. The temperature of the box of the composite spinning assembly is 275-295°C.

If the temperature of the box is lower, the spinning condition will be poor, and the end will be easily broken; if the temperature of the box is higher, the strength of the fiber will be lower and the performance will be reduced.

Preferably, in step 5), the temperature of the first hot roll is 70-90° C., the temperature of the second hot roll is 130-180° C., and the stretching ratio is 3.0-4.0.

The temperature of the hot roll and the stretching ratio are controlled within the above range, which can make the fiber have better strength and suitable elongation at break.

Therefore, the present invention has the following beneficial effects:

(1) provide a kind of preparation method of graphene modified PET blended fiber, by improving the dispersibility of graphene sheet itself, to improve the uniformity of graphene distribution in the composite fiber, to achieve the graphene modification with excellent performance The composite fiber of PET is the fiber itself with good mechanical properties;

(2) By spinning the graphene master batch chips and the PET chips with a composite spinneret, a skin-core structure with a four-leaf clover structure is prepared, so as to obtain a polyester with high elasticity, high renaturation, high oil absorption, and high impact resistance. A graphene-modified composite fiber with properties such as antistatic, antistatic, antibacterial, and far-infrared properties in one, the preparation process is simple, and the cost is saved.

Description of drawings

Figure 1 is a cross-sectional view of a composite spinneret.

Fig. 2 is a schematic cross-sectional view of the composite fiber.

In the picture: A, PET spinning, B, graphene modified spinning.

Detailed ways

General Example

A preparation method of graphene-modified PET blended fiber, comprising the following steps:

1) Preparation of modified graphene: under ice bath conditions, add graphite and sodium nitrate to a round-bottomed flask, pour in concentrated sulfur and stir to form a paste, slowly add potassium permanganate, control the temperature not to exceed 20 °C, and stir for 1.5 -2h. Then the temperature was raised to 35-40°C and kept for 2-2.5h. Distilled water was added dropwise and the temperature was raised to 98-100°C, at which point a golden yellow suspension appeared. Add hydrogen peroxide while hot, pour into distilled water, ultrasonically disperse 1-1.2h to obtain graphene oxide mixture, slowly add cationic modifier DMSO and/or tributylphosphine containing long carbon chain to the above mixture, stir for 10- 15min to get a reddish-brown precipitate, centrifuged, alternately washed with hydrochloric acid solution and distilled water for 3-5 times, vacuum freeze-dried for 22-24h to obtain a brown complex; ultrasonically dispersed the complex in distilled water, add hydrazine hydrate solution, at 78-80 The reaction was stirred in an oil bath for 10-12 h. After the reaction is completed, the system is a black suspension, washed with hydrochloric acid solution and distilled water alternately for 3-5 times, and vacuum freeze-dried to obtain black powdery modified graphene;

2) Preparation of modified graphene chips: after the modified graphene and the PET chip powder are respectively dried, the graphene powder, the PET chip powder and the modifier are added into a high-speed disperser for sufficient dispersion and mixing. The mixed powder is added to a twin-screw extruder for melt extrusion and granulation to obtain graphene-modified PET chips; the proportion of modified cationic graphene in the blend is 1%-5%, and the proportion of PET chip powder is It is 95%-98.9%, and the proportion of modifier is 0.1%-1%; the temperature of the first to fifth zones of the twin-screw extruder screw is 245-255 ℃, 260-270 ℃, 265-275 ℃, 265- 275℃, 260-270℃;

3) Melting: according to the mass ratio of 20:80-40:60, the graphene-modified PET chips and the PET chips are respectively dried and then melted by a screw extruder (280-310° C.), and the obtained graphene-modified PET chips are spun. Melt and PET chip spinning melt;

4) Blending: The two spinning melts enter the bi-component composite spinning assembly through their corresponding pipes respectively for spinning (the temperature of the spinning box is 275-295 ° C). The silk plate is ejected to form silk strips;

5) Post-processing: After the strands are cooled, oiled, stretched and shaped and wound (the temperature of the first hot roll is 70-90°C, the temperature of the second hot roll is 130-180°C; the stretching ratio is 3.0-4.0 ; side blowing wind speed 0.7-1.0m/s) to obtain modified graphene composite fibers; two components in the modified graphene composite fibers are combined in a skin-core type, and the fiber cross section is a four-leaf clover type.

Wherein, the intrinsic viscosity of the PET chips is 0.65±0.2 dL/g, the melting point is 240-265° C., and the moisture content of the dry chips is less than 50 ppm.

Example 1

A preparation method of graphene-modified PET blended fiber, comprising the following steps:

1) Preparation of modified graphene: under ice bath conditions, add graphite and sodium nitrate to a round-bottomed flask, pour in concentrated sulfur and stir to form a paste, slowly add potassium permanganate, control the temperature to 15°C, and stir for 1.8h . Then the temperature was raised to 37°C and held for 2.3h. Distilled water was added dropwise and the temperature was raised to 99°C, at which point a golden yellow suspension appeared. Add hydrogen peroxide while hot, pour into distilled water, ultrasonically disperse 1.1h to obtain graphene oxide mixture, slowly add cationic modifier DMSO and/or tributylphosphine containing long carbon chain to the above mixture, stir for 12min to obtain reddish-brown Precipitation, centrifugation, alternately washing with hydrochloric acid solution and distilled water 4 times, vacuum freeze drying for 23h to obtain a brown complex; ultrasonically dispersing the complex in distilled water, adding hydrazine hydrate solution, stirring and reacting in an oil bath at 79°C for 11h. After the reaction is completed, the system is a black suspension, washed 4 times with hydrochloric acid solution and distilled water alternately, and vacuum freeze-dried to obtain black powder modified graphene;

2) Preparation of modified graphene chips: after the modified graphene and the PET chip powder are respectively dried, the graphene powder, the PET chip powder and the modifier are added into a high-speed disperser for sufficient dispersion and mixing. The mixed powder is added to a twin-screw extruder for melt extrusion and granulation to obtain graphene-modified PET chips; the proportion of modified cationic graphene in the blend is 3%, and the proportion of PET chip powder is 96.5% , the proportion of modifier is 0.5%; the temperatures of the first to fifth zones of the twin-screw extruder screw are 250°C, 265°C, 270°C, 270°C, and 265°C, respectively;

3) Melting: according to the mass ratio of 50:50, the graphene-modified PET chips and the PET chips are respectively dried and then melted by a screw extruder (300° C.), and the obtained graphene-modified PET chips spinning melt and PET chips spinning melt. wire melt;

4) Blending: The two spinning melts enter the bi-component composite spinning assembly through their respective pipes for spinning (the temperature of the spinning box is 280°C). The two spinning melts are spun from a special composite spinneret. Squirting to form filaments;

5) Post-processing: after the strands are cooled, oiled, stretched, shaped and wound (the temperature of the first hot roll is 75°C, the temperature of the second hot roll is 150°C; the stretching ratio is 3.5; the side blowing wind speed is 0.8m /s) to obtain a modified graphene composite fiber; the two components in the modified graphene composite fiber are combined in a skin-core type, and the fiber cross-section is a four-leaf clover type.

The specification of the self-crimping composite filament prepared by the above process is 100dtex/36f.

Example 2

The settings and working principles of this embodiment are the same as those of Embodiment 1, the differences are:

A preparation method of graphene-modified PET blended fiber, comprising the following steps:

1) Preparation of modified graphene: under ice bath conditions, add graphite and sodium nitrate to a round-bottomed flask, pour in concentrated sulfur and stir to form a paste, slowly add potassium permanganate, control the temperature not to exceed 20 °C, and stir for 1.5 -2h. Then the temperature was raised to 35-40°C and kept for 2-2.5h. Distilled water was added dropwise and the temperature was raised to 98-100°C, at which point a golden yellow suspension appeared. Add hydrogen peroxide while hot, pour into distilled water, ultrasonically disperse 1-1.2h to obtain graphene oxide mixture, slowly add cationic modifier DMSO and/or tributylphosphine containing long carbon chain to the above mixture, stir for 10- 15min to get a reddish-brown precipitate, centrifuged, alternately washed with hydrochloric acid solution and distilled water for 3-5 times, vacuum freeze-dried for 22-24h to obtain a brown complex; ultrasonically dispersed the complex in distilled water, add hydrazine hydrate solution, at 78-80 The reaction was stirred in an oil bath for 10-12 h. After the reaction is completed, the system is a black suspension, washed with hydrochloric acid solution and distilled water alternately for 3-5 times, and vacuum freeze-dried to obtain black powdery modified graphene;

2) Preparation of modified graphene chips: after the modified graphene and the PET chip powder are respectively dried, the graphene powder, the PET chip powder and the modifier are added into a high-speed disperser for sufficient dispersion and mixing. The mixed powder is added to a twin-screw extruder for melt extrusion and granulation to obtain graphene-modified PET chips; the proportion of modified cationic graphene in the blend is 1%-5%, and the proportion of PET chip powder is It is 95%-98.9%, and the proportion of modifier is 0.1%-1%; the temperature of the first to fifth zones of the twin-screw extruder screw is 245-255 ℃, 260-270 ℃, 265-275 ℃, 265- 275℃, 260-270℃;

3) Melting: according to the mass ratio of 20:80-40:60, the graphene-modified PET chips and the PET chips are respectively dried and then melted by a screw extruder (280-310° C.), and the obtained graphene-modified PET chips are spun. Melt and PET chip spinning melt;

4) Blending: The two spinning melts enter the bi-component composite spinning assembly through their corresponding pipes respectively for spinning (the temperature of the spinning box is 275-295 ° C). The silk plate is ejected to form silk strips;

5) Post-treatment: After the strands are cooled, oiled, stretched and shaped and wound (the temperature of the first hot roll is 70°C, the temperature of the second hot roll is 180°C; the stretching ratio is 3.0-4.0; 0.7-1.0 m/s) to obtain a modified graphene composite fiber; the two components in the modified graphene composite fiber are combined in a skin-core type, and the fiber cross-section is a four-leaf clover shape.

The specification of the self-crimping composite filament prepared by the above process is 100dtex/24f.

Example 3

The settings and working principles of this embodiment are the same as those of Embodiment 1, the differences are:

A preparation method of graphene-modified PET blended fiber, comprising the following steps:

1) Preparation of modified graphene: under ice bath conditions, add graphite and sodium nitrate to a round-bottomed flask, pour in concentrated sulfur and stir to form a paste, slowly add potassium permanganate, control the temperature not to exceed 20 °C, and stir for 1.5 -2h. Then the temperature was raised to 35-40°C and kept for 2-2.5h. Distilled water was added dropwise and the temperature was raised to 98-100°C, at which point a golden yellow suspension appeared. Add hydrogen peroxide while hot, pour into distilled water, ultrasonically disperse 1-1.2h to obtain graphene oxide mixture, slowly add cationic modifier DMSO and/or tributylphosphine containing long carbon chain to the above mixture, stir for 10- 15min to get a reddish-brown precipitate, centrifuged, alternately washed with hydrochloric acid solution and distilled water for 3-5 times, vacuum freeze-dried for 22-24h to obtain a brown complex; ultrasonically dispersed the complex in distilled water, add hydrazine hydrate solution, at 78-80 The reaction was stirred in an oil bath for 10-12 h. After the reaction is completed, the system is a black suspension, washed with hydrochloric acid solution and distilled water alternately for 3-5 times, and vacuum freeze-dried to obtain black powdery modified graphene;

2) Preparation of modified graphene chips: after the modified graphene and the PET chip powder are respectively dried, the graphene powder, the PET chip powder and the modifier are added into a high-speed disperser for sufficient dispersion and mixing. The mixed powder is added to a twin-screw extruder for melt extrusion and granulation to obtain graphene-modified PET chips; the proportion of modified cationic graphene in the blend is 1%-5%, and the proportion of PET chip powder is It is 95%-98.9%, and the proportion of modifier is 0.1%-1%; the temperature of the first to fifth zones of the twin-screw extruder screw is 245-255 ℃, 260-270 ℃, 265-275 ℃, 265- 275℃, 260-270℃;

3) Melting: according to the mass ratio of 20:80-40:60, the graphene-modified PET chips and the PET chips are respectively dried and then melted by a screw extruder (280-310° C.), and the obtained graphene-modified PET chips are spun. Melt and PET chip spinning melt;

4) Blending: The two spinning melts enter the bi-component composite spinning assembly through their corresponding pipes respectively for spinning (the temperature of the spinning box is 275-295 ° C). The silk plate is ejected to form silk strips;

5) Post-processing: After the strands are cooled, oiled, stretched and shaped and wound (the temperature of the first hot roll is 90°C, the temperature of the second hot roll is 130°C; the stretching ratio is 3.0-4.0; 0.7-1.0 m/s) to obtain a modified graphene composite fiber; the two components in the modified graphene composite fiber are combined in a skin-core type, and the fiber cross-section is a four-leaf clover shape.

The specification of the self-crimping composite filament prepared by the above process is 100dtex/36f.

Example 4

The settings and working principles of this embodiment are the same as those of Embodiment 1, the differences are:

A preparation method of graphene-modified PET blended fiber, comprising the following steps:

1) Preparation of modified graphene: under ice bath conditions, add graphite and sodium nitrate to a round-bottomed flask, pour in concentrated sulfur and stir to form a paste, slowly add potassium permanganate, control the temperature not to exceed 20 °C, and stir for 1.5 -2h. Then the temperature was raised to 35-40°C and kept for 2-2.5h. Distilled water was added dropwise and the temperature was raised to 98-100°C, at which point a golden yellow suspension appeared. Add hydrogen peroxide while hot, pour into distilled water, ultrasonically disperse 1-1.2h to obtain graphene oxide mixture, slowly add cationic modifier DMSO and/or tributylphosphine containing long carbon chain to the above mixture, stir for 10- 15min to get a reddish-brown precipitate, centrifuged, alternately washed with hydrochloric acid solution and distilled water for 3-5 times, vacuum freeze-dried for 22-24h to obtain a brown complex; ultrasonically dispersed the complex in distilled water, add hydrazine hydrate solution, at 78-80 The reaction was stirred in an oil bath for 10-12 h. After the reaction is completed, the system is a black suspension, washed with hydrochloric acid solution and distilled water alternately for 3-5 times, and vacuum freeze-dried to obtain black powdery modified graphene;

2) Preparation of modified graphene chips: after the modified graphene and the PET chip powder are respectively dried, the graphene powder, the PET chip powder and the modifier are added into a high-speed disperser for sufficient dispersion and mixing. The mixed powder is added to a twin-screw extruder for melt extrusion and granulation to obtain graphene-modified PET chips; the proportion of modified cationic graphene in the blend is 1%-5%, and the proportion of PET chip powder is It is 95%-98.9%, and the proportion of modifier is 0.1%-1%; the temperature of the first to fifth zones of the twin-screw extruder screw is 245-255 ℃, 260-270 ℃, 265-275 ℃, 265- 275℃, 260-270℃;

3) Melting: according to the mass ratio of 20:80-40:60, the graphene-modified PET chips and the PET chips are respectively dried and then melted by a screw extruder (280-310° C.), and the obtained graphene-modified PET chips are spun. Melt and PET chip spinning melt;

4) Blending: The two spinning melts enter the bi-component composite spinning assembly through their corresponding pipes respectively for spinning (the temperature of the spinning box is 275-295 ° C). The silk plate is ejected to form silk strips;

5) Post-processing: After the strands are cooled, oiled, stretched and shaped and wound (the temperature of the first hot roller is 80°C, the temperature of the second hot roller is 170°C; the stretching ratio is 3.0-4.0; 0.7-1.0 m/s) to obtain a modified graphene composite fiber; the two components in the modified graphene composite fiber are combined in a skin-core type, and the fiber cross-section is a four-leaf clover shape.

The specification of the self-crimping composite filament prepared by the above process is 100dtex/24f.

Example 5

The settings and working principles of this embodiment are the same as those of Embodiment 1, the differences are:

A preparation method of graphene-modified PET blended fiber, comprising the following steps:

1) Preparation of modified graphene: under ice bath conditions, add graphite and sodium nitrate to a round-bottomed flask, pour in concentrated sulfur and stir to form a paste, slowly add potassium permanganate, control the temperature not to exceed 20 °C, and stir for 1.5 -2h. Then the temperature was raised to 35-40°C and kept for 2-2.5h. Distilled water was added dropwise and the temperature was raised to 98-100°C, at which point a golden yellow suspension appeared. Add hydrogen peroxide while hot, pour into distilled water, ultrasonically disperse 1-1.2h to obtain graphene oxide mixture, slowly add cationic modifier DMSO and/or tributylphosphine containing long carbon chain to the above mixture, stir for 10- 15min to get a reddish-brown precipitate, centrifuged, alternately washed with hydrochloric acid solution and distilled water for 3-5 times, vacuum freeze-dried for 22-24h to obtain a brown complex; ultrasonically dispersed the complex in distilled water, add hydrazine hydrate solution, at 78-80 The reaction was stirred in an oil bath for 10-12 h. After the reaction is completed, the system is a black suspension, washed with hydrochloric acid solution and distilled water alternately for 3-5 times, and vacuum freeze-dried to obtain black powdery modified graphene;

2) Preparation of modified graphene chips: after the modified graphene and the PET chip powder are respectively dried, the graphene powder, the PET chip powder and the modifier are added into a high-speed disperser for sufficient dispersion and mixing. The mixed powder is added to a twin-screw extruder for melt extrusion and granulation to obtain graphene-modified PET chips; the proportion of modified cationic graphene in the blend is 1%-5%, and the proportion of PET chip powder is It is 95%-98.9%, and the proportion of modifier is 0.1%-1%; the temperature of the first to fifth zones of the twin-screw extruder screw is 245-255 ℃, 260-270 ℃, 265-275 ℃, 265- 275℃, 260-270℃;

3) Melting: according to the mass ratio of 20:80-40:60, the graphene-modified PET chips and the PET chips are respectively dried and then melted by a screw extruder (280-310° C.), and the obtained graphene-modified PET chips are spun. Melt and PET chip spinning melt;

4) Blending: The two spinning melts enter the bi-component composite spinning assembly through their corresponding pipes respectively for spinning (the temperature of the spinning box is 275-295 ° C). The silk plate is ejected to form silk strips;

5) Post-processing: after the strands are cooled, oiled, stretched, shaped and wound (the temperature of the first hot roll is 85 °C, the temperature of the second hot roll is 160 °C; the stretching ratio is 3.0-4.0; 0.7-1.0 m/s) to obtain a modified graphene composite fiber; the two components in the modified graphene composite fiber are combined in a skin-core type, and the fiber cross-section is a four-leaf clover shape.

The specification of the self-crimping composite filament prepared by the above process is 100dtex/36f.

Comparative Example 1 (The difference from Example 1 is that the graphene content in the graphene-modified PET chips exceeds the preferred ratio, and the proportion of graphene is 7%.)

The setting and working principle of this comparative example are the same as those of Example 1:

A preparation method of graphene-modified PET blended fiber, comprising the following steps:

1) Preparation of modified graphene: under ice bath conditions, add graphite and sodium nitrate to a round-bottomed flask, pour in concentrated sulfur and stir to form a paste, slowly add potassium permanganate, control the temperature to 15°C, and stir for 1.8h . Then the temperature was raised to 37°C and held for 2.3h. Distilled water was added dropwise and the temperature was raised to 99°C, at which point a golden yellow suspension appeared. Add hydrogen peroxide while hot, pour into distilled water, ultrasonically disperse 1.1h to obtain graphene oxide mixture, slowly add cationic modifier DMSO and/or tributylphosphine containing long carbon chain to the above mixture, stir for 12min to obtain reddish-brown Precipitation, centrifugation, alternately washing with hydrochloric acid solution and distilled water 4 times, vacuum freeze drying for 23h to obtain a brown complex; ultrasonically dispersing the complex in distilled water, adding hydrazine hydrate solution, stirring and reacting in an oil bath at 79°C for 11h. After the reaction is completed, the system is a black suspension, washed 4 times with hydrochloric acid solution and distilled water alternately, and vacuum freeze-dried to obtain black powder modified graphene;

2) Preparation of modified graphene chips: after the modified graphene and the PET chip powder are respectively dried, the graphene powder, the PET chip powder and the modifier are added into a high-speed disperser for sufficient dispersion and mixing. The mixed powder is added to a twin-screw extruder for melt extrusion and granulation to obtain graphene-modified PET chips; the proportion of modified cationic graphene in the blend is 7%, and the proportion of PET chip powder is 92% , the proportion of modifier is 1%; the temperatures of the first to fifth zones of the twin-screw extruder screw are 250 °C, 265 °C, 270 °C, 270 °C, and 265 °C, respectively;

3) Melting: according to the mass ratio of 50:50, the graphene-modified PET chips and the PET chips are respectively dried and then melted by a screw extruder (300° C.), and the obtained graphene-modified PET chips spinning melt and PET chips spinning melt. wire melt;

4) Blending: The two spinning melts enter the bi-component composite spinning assembly through their respective pipes for spinning (the temperature of the spinning box is 280°C). The two spinning melts are spun from a special composite spinneret. Squirting to form filaments;

5) Post-processing: after the strands are cooled, oiled, stretched, shaped and wound (the temperature of the first hot roll is 75°C, the temperature of the second hot roll is 150°C; the stretching ratio is 3.5; the side blowing wind speed is 0.8m /s) to obtain a modified graphene composite fiber; the two components in the modified graphene composite fiber are combined in a skin-core type, and the fiber cross-section is a four-leaf clover type.

The specification of the self-crimping composite filament prepared by the above process is 100dtex/36f.

Comparative Example 2 (The difference from Example 1 is that skin-core composite spinning is performed, and the fiber structure is concentric.) This comparative example has the same setting and working principle as Example 1, the difference is:

A preparation method of graphene-modified PET blended fiber, comprising the following steps:

1) Preparation of modified graphene: under ice bath conditions, add graphite and sodium nitrate to a round-bottomed flask, pour in concentrated sulfur and stir to form a paste, slowly add potassium permanganate, control the temperature to 15°C, and stir for 1.8h . Then the temperature was raised to 37°C and held for 2.3h. Distilled water was added dropwise and the temperature was raised to 99°C, at which point a golden yellow suspension appeared. Add hydrogen peroxide while hot, pour into distilled water, ultrasonically disperse 1.1h to obtain graphene oxide mixture, slowly add cationic modifier DMSO and/or tributylphosphine containing long carbon chain to the above mixture, stir for 12min to obtain reddish-brown Precipitation, centrifugation, alternately washing with hydrochloric acid solution and distilled water 4 times, vacuum freeze drying for 23h to obtain a brown complex; ultrasonically dispersing the complex in distilled water, adding hydrazine hydrate solution, stirring and reacting in an oil bath at 79°C for 11h. After the reaction is completed, the system is a black suspension, washed 4 times with hydrochloric acid solution and distilled water alternately, and vacuum freeze-dried to obtain black powder modified graphene;

2) Preparation of modified graphene chips: after the modified graphene and the PET chip powder are respectively dried, the graphene powder, the PET chip powder and the modifier are added into a high-speed disperser for sufficient dispersion and mixing. The mixed powder is added to a twin-screw extruder for melt extrusion and granulation to obtain graphene-modified PET chips; the proportion of modified cationic graphene in the blend is 3%, and the proportion of PET chip powder is 96.5% , the proportion of modifier is 0.5%; the temperatures of the first to fifth zones of the twin-screw extruder screw are 250°C, 265°C, 270°C, 270°C, and 265°C, respectively;

3) Melting: according to the mass ratio of 50:50, the graphene-modified PET chips and the PET chips are respectively dried and then melted by a screw extruder (300° C.), and the obtained graphene-modified PET chips spinning melt and PET chips spinning melt. wire melt;

4) Blending: The two spinning melts enter the bi-component composite spinning assembly through their corresponding pipes for spinning (the temperature of the spinning box is 280°C), and the two spinning melts are spun from the skin-core composite spinning assembly. The filaments are formed by ejecting from the spinneret;

5) Post-processing: after the strands are cooled, oiled, stretched, shaped and wound (the temperature of the first hot roll is 75°C, the temperature of the second hot roll is 150°C; the stretching ratio is 3.5; the side blowing wind speed is 0.8m /s) to obtain a modified graphene composite fiber; the two components in the modified graphene composite fiber are combined in a skin-core type, and the fiber cross-section has a concentric circular structure.

The specification of the self-crimping composite filament prepared by the above process is 100dtex/36f.

Comparative example 3 (the difference from the embodiment is that the temperature of the spinning box and the temperature of the heating roller are beyond the optimal range during the spinning process; the temperature of the spinning box is 305°C, the temperature of the first heating roller is 105°C; the temperature of the second heating roller 185°C.)

A preparation method of graphene-modified PET blended fiber, comprising the following steps:

1) Preparation of modified graphene: under ice bath conditions, add graphite and sodium nitrate to a round-bottomed flask, pour in concentrated sulfur and stir to form a paste, slowly add potassium permanganate, control the temperature to 15°C, and stir for 1.8h . Then the temperature was raised to 37°C and held for 2.3h. Distilled water was added dropwise and the temperature was raised to 99°C, at which point a golden yellow suspension appeared. Add hydrogen peroxide while hot, pour into distilled water, ultrasonically disperse 1.1h to obtain graphene oxide mixture, slowly add cationic modifier DMSO and/or tributylphosphine containing long carbon chain to the above mixture, stir for 12min to obtain reddish-brown Precipitation, centrifugation, alternately washing with hydrochloric acid solution and distilled water 4 times, vacuum freeze drying for 23h to obtain a brown complex; ultrasonically dispersing the complex in distilled water, adding hydrazine hydrate solution, stirring and reacting in an oil bath at 79°C for 11h. After the reaction is completed, the system is a black suspension, washed 4 times with hydrochloric acid solution and distilled water alternately, and vacuum freeze-dried to obtain black powder modified graphene;

2) Preparation of modified graphene chips: after the modified graphene and the PET chip powder are respectively dried, the graphene powder, the PET chip powder and the modifier are added into a high-speed disperser for sufficient dispersion and mixing. The mixed powder is added to a twin-screw extruder for melt extrusion and granulation to obtain graphene-modified PET chips; the proportion of modified cationic graphene in the blend is 3%, and the proportion of PET chip powder is 96.5% , the proportion of modifier is 0.5%; the temperatures of the first to fifth zones of the twin-screw extruder screw are 250°C, 265°C, 270°C, 270°C, and 265°C, respectively;

3) Melting: according to the mass ratio of 50:50, the graphene-modified PET chips and the PET chips are respectively dried and then melted by a screw extruder (300° C.), and the obtained graphene-modified PET chips spinning melt and PET chips spinning melt. wire melt;

4) Blending: The two spinning melts enter the bi-component composite spinning assembly through their corresponding pipes for spinning (the temperature of the spinning box is 305°C), and the two spinning melts are produced from a special composite spinneret. Squirting to form filaments;

5) Post-processing: After the strands are cooled, oiled, stretched, shaped and wound (the temperature of the first hot roll is 105 °C, the temperature of the second hot roll is 185 °C; the stretching ratio is 3.5; the side blowing wind speed is 0.8m /s) to obtain a modified graphene composite fiber; the two components in the modified graphene composite fiber are combined in a skin-core type, and the fiber cross-section is a four-leaf clover type.

The specification of the self-crimping composite filament prepared by the above process is 100dtex/36f.

Comparative Example 4 (The difference from the example is that the graphene is not cationically modified.)

A preparation method of graphene-modified PET blended fiber, comprising the following steps:

1) Preparation of graphene chips: after the graphene and the PET chip powder are respectively dried, the graphene powder, the PET chip powder and the modifier are added into a high-speed disperser for sufficient dispersion and mixing. The mixed powder is added to a twin-screw extruder for melt extrusion and granulation to obtain graphene-modified PET chips; the proportion of modified cationic graphene in the blend is 1%-5%, and the proportion of PET chip powder is It is 95%-98.9%, and the proportion of modifier is 0.1%-1%; the temperature of the first to fifth zones of the twin-screw extruder screw is 245-255 ℃, 260-270 ℃, 265-275 ℃, 265- 275℃, 260-270℃;

2) Melting: according to the mass ratio of 50:50, the graphene-modified PET chips and the PET chips are respectively dried and then melted by a screw extruder (300° C.), and the obtained graphene-modified PET chips spinning melt and PET chips are spinning. wire melt;

3) Blending: The two spinning melts enter the bi-component composite spinning assembly through their corresponding pipes for spinning (the temperature of the spinning box is 280°C). The two spinning melts are spun from a special composite spinneret. Squirting to form filaments;

4) Post-treatment: After the strands are cooled, oiled, stretched, shaped and wound (the temperature of the first hot roll is 75 °C, the temperature of the second hot roll is 150 °C; the stretching ratio is 3.5; the side blowing wind speed is 0.8m /s) to obtain a modified graphene composite fiber; the two components in the modified graphene composite fiber are combined in a skin-core type, and the fiber cross-section is a four-leaf clover type.

The specification of the self-crimping composite filament prepared by the above process is 100dtex/36f.

Comparative Example 5 (The difference from the example is that 1.3-dimethylphthalate-5-sodium sulfonate is used for cationic modification.)

A preparation method of graphene-modified PET blended fiber, comprising the following steps:

1) Preparation of modified graphene: under ice bath conditions, add graphite and sodium nitrate to a round-bottomed flask, pour in concentrated sulfur and stir to form a paste, slowly add potassium permanganate, control the temperature to 15°C, and stir for 1.8h . Then the temperature was raised to 37°C and held for 2.3h. Distilled water was added dropwise and the temperature was raised to 99°C, at which point a golden yellow suspension appeared. Add hydrogen peroxide while still hot, pour it into distilled water, ultrasonically disperse for 1.1 h to obtain a graphene oxide mixture, slowly add the cationic modifier 1.3-dimethylphthalate-5-sodium sulfonate to the above mixture, and stir for 12 min to obtain a graphene oxide mixture. The red-brown precipitate was centrifuged, washed alternately with hydrochloric acid solution and distilled water for 4 times, and vacuum freeze-dried for 23 h to obtain a brown complex; the complex was ultrasonically dispersed in distilled water, added with hydrazine hydrate solution, and stirred for 11 h in an oil bath at 79 °C. After the reaction is completed, the system is a black suspension, washed 4 times with hydrochloric acid solution and distilled water alternately, and vacuum freeze-dried to obtain black powder modified graphene;

2) Preparation of modified graphene chips: after the modified graphene and the PET chip powder are respectively dried, the graphene powder, the PET chip powder and the modifier are added into a high-speed disperser for sufficient dispersion and mixing. The mixed powder is added to a twin-screw extruder for melt extrusion and granulation to obtain graphene-modified PET chips; the proportion of modified cationic graphene in the blend is 3%, and the proportion of PET chip powder is 96.5% , the proportion of modifier is 0.5%; the temperatures of the first to fifth zones of the twin-screw extruder screw are 250°C, 265°C, 270°C, 270°C, and 265°C, respectively;

3) Melting: according to the mass ratio of 50:50, the graphene-modified PET chips and the PET chips are respectively dried and then melted by a screw extruder (300° C.), and the obtained graphene-modified PET chips spinning melt and PET chips spinning melt. wire melt;

4) Blending: The two spinning melts enter the bi-component composite spinning assembly through their respective pipes for spinning (the temperature of the spinning box is 280°C). The two spinning melts are spun from a special composite spinneret. Squirting to form filaments;

5) Post-processing: after the strands are cooled, oiled, stretched, shaped and wound (the temperature of the first hot roll is 75°C, the temperature of the second hot roll is 150°C; the stretching ratio is 3.5; the side blowing wind speed is 0.8m /s) to obtain a modified graphene composite fiber; the two components in the modified graphene composite fiber are combined in a skin-core type, and the fiber cross-section is a four-leaf clover type.

The specification of the self-crimping composite filament prepared by the above process is 100dtex/36f.

Comparative Example 6 (The difference from Example is that no modifier was added during blending.)

1) Preparation of modified graphene: under ice bath conditions, add graphite and sodium nitrate to a round-bottomed flask, pour in concentrated sulfur and stir to form a paste, slowly add potassium permanganate, control the temperature to 15°C, and stir for 1.8h . Then the temperature was raised to 37°C and held for 2.3h. Distilled water was added dropwise and the temperature was raised to 99°C, at which point a golden yellow suspension appeared. Add hydrogen peroxide while hot, pour into distilled water, ultrasonically disperse 1.1h to obtain graphene oxide mixture, slowly add cationic modifier DMSO and/or tributylphosphine containing long carbon chain to the above mixture, stir for 12min to obtain reddish-brown Precipitation, centrifugation, alternately washing with hydrochloric acid solution and distilled water 4 times, vacuum freeze drying for 23h to obtain a brown complex; ultrasonically dispersing the complex in distilled water, adding hydrazine hydrate solution, stirring and reacting in an oil bath at 79°C for 11h. After the reaction is completed, the system is a black suspension, washed 4 times with hydrochloric acid solution and distilled water alternately, and vacuum freeze-dried to obtain black powder modified graphene;

2) Preparation of modified graphene chips: after the modified graphene and the PET chip powder are respectively dried, the graphene powder and the PET chip powder are added to a high-speed disperser for sufficient dispersion and mixing. The mixed powder is added to a twin-screw extruder for melt extrusion and granulation to obtain graphene-modified PET chips; the proportion of modified cationic graphene in the blend is 3%, and the proportion of PET chip powder is 96.5% , the proportion of modifier is 0.5%; the temperatures of the first to fifth zones of the twin-screw extruder screw are 250°C, 265°C, 270°C, 270°C, and 265°C, respectively;

3) Melting: according to the mass ratio of 50:50, the graphene-modified PET chips and the PET chips are respectively dried and then melted by a screw extruder (300° C.), and the obtained graphene-modified PET chips spinning melt and PET chips spinning melt. wire melt;

4) Blending: The two spinning melts enter the bi-component composite spinning assembly through their respective pipes for spinning (the temperature of the spinning box is 280°C). The two spinning melts are spun from a special composite spinneret. Squirting to form filaments;

5) Post-processing: after the strands are cooled, oiled, stretched, shaped and wound (the temperature of the first hot roll is 75°C, the temperature of the second hot roll is 150°C; the stretching ratio is 3.5; the side blowing wind speed is 0.8m /s) to obtain a modified graphene composite fiber; the two components in the modified graphene composite fiber are combined in a skin-core type, and the fiber cross-section is a four-leaf clover type.

The specification of the self-crimping composite filament prepared by the above process is 100dtex/36f.

The evaluation parameters of the composite spinning fibers obtained in Examples 1-5 and Comparative Examples 1-6 are shown in Table 1.

The filaments prepared in the above examples were tested for the strength of composite fiber fabrics according to "GB/T-14337 Filament Tensile Properties Test Method", and the water absorption of composite fiber fabrics was tested according to "GB/T12703.4-2010". The conductivity of the composite fiber fabric was tested according to "GBT 1410-2006". According to the textile industry standard of the People's Republic of China FZT 54042-2011, it can be seen that when the fiber volume specific resistance is 105 ~ 108Ω·cm, the fiber It has excellent antistatic properties and is an excellent product. See Table 1 for details.

Table 1 Main preparation process and fiber physical index

Conclusion: Combining the above-mentioned examples and the comparative examples in Table 1, it can be seen that the present application uses blended modified graphene PET chips and PET chips as two components and then melts and extrudes them through a screw extruder, respectively, into two components. The composite spinning equipment and the specially designed fan-blade composite spinneret hole, the sprayed melt, after cooling, oiling, drawing, heat setting and winding, the mechanical properties of the obtained fibers meet the relevant standard requirements. Due to its suitable component ratio, excellent spinneret design and excellent spinning process, the obtained composite fiber has the characteristics of high strength, good moisture absorption and perspiration, the graphene components are evenly dispersed, no agglomeration occurs, and the fiber is also It has good antistatic properties and is a high value-added fiber.

Take Example 1 to carry out the water absorption test, the measured value is 228%, which meets the standard requirement ≥ 200%, and the rest of the examples also meet the standard.

The difference between Comparative Example 1 and Example 1 is that the proportion of modified graphene added during blending is too high, so that graphene cannot be fully dispersed and evenly dispersed, and partial agglomeration occurs, which is not conducive to its subsequent processing, and cannot exert its resistance. Static properties and moisture wicking ability, the mechanical properties of the fiber have declined.

The difference between Comparative Example 2 and Example 1 is that the obtained fiber does not use a specially designed four-leaf clover spinneret, so although the obtained fiber has good antistatic properties, its strength is significantly reduced, and graphene is used more, The cost is relatively high and cannot be compared with the fibers obtained in Example 1.

The difference between Comparative Example 3 and Example 1 is that the spinning temperature of the obtained fiber is relatively high, which results in partial degradation of the obtained fiber, and the obtained fiber cannot have strength, and because the winding temperature is too high, the obtained fiber is poorly formed and cannot meet the follow-up requirements. Processing and other steps, the resulting fibers have poor performance.

The difference between Comparative Example 4 and Example 1 is that graphene is not cationically modified, and although the obtained fiber has antistatic properties, its mechanical properties and antistatic properties are all lower than those in Example 1 using cations to graphene. The fibers obtained after modification, it can be seen that the cationic modification of graphene can better disperse it uniformly, without agglomeration, so that the fibers have excellent properties.

The difference between Comparative Example 5 and Example 1 is that, instead of using DMSO and/or tributyl phosphine containing a long carbon chain, the conventional modifier 1.3-dimethyl phthalate-5-sodium sulfonate was used to conduct graphene. Cationic modification, it can be seen that the performance indicators of the modified modified graphene composite fibers are lower than those obtained by using the cationic modifier DMSO and/or the fibers containing long carbon chain tributylphosphine, which is due to isophthalic Dimethyl formate-5-sodium sulfonate is generally used for the modification of conventional polyester, because it has a benzene ring, and there may be a force between it and graphene, so it cannot be modified well, so less effective.

The difference between Comparative Example 6 and Example 1 is that no modifier was added when preparing the modified graphene PET chips for blending, and the properties of the obtained fibers were quite different. This is because adding the modifier can make the dispersion effect of graphene. More preferably, the antistatic effect and strength of the fibers obtained without the addition of the modifier are lower than those obtained with the addition of the modifier.

From the data of Examples 1-5 and Comparative Examples 1-6, it can be seen that only the scheme within the scope of the claims of the present invention can satisfy the above requirements in all aspects, and obtain the optimal synthesis scheme. And for the change of the ratio, the replacement/addition/subtraction of raw materials, or the change of the feeding sequence, it will bring corresponding negative effects.

The raw materials and equipment used in the present invention, unless otherwise specified, are the common raw materials and equipment in the art; the methods used in the present invention, unless otherwise specified, are the conventional methods in the art.

The above are only preferred embodiments of the present invention and do not limit the present invention. Any simple modifications, changes and equivalent transformations made to the above embodiments according to the technical essence of the present invention still belong to the technical solutions of the present invention. scope of protection.

Claims (10)

1. A preparation method of graphene modified PET blended fiber is characterized by comprising the following preparation steps:

1) modifying graphene with a cationic modifier;

2) preparing a graphene modified slice: blending modified cationic graphene, a modifier and PET slice powder, and granulating by using a double-screw extruder to obtain graphene modified slices;

3) melting: respectively melting the dried PET slices and the graphene modified slice by screw extruders to obtain a PET spinning melt and a graphene modified slice spinning melt;

4) blending: the two spinning melts respectively enter the two-component composite spinning assembly through respective corresponding pipelines to be spun, and the two spinning melts are sprayed out from a composite spinneret plate to form a blended fiber;

5) and (3) post-treatment: and cooling, oiling, stretching, shaping and winding the blended fiber to obtain a finished product.

2. The preparation method of the graphene-modified PET blended fiber according to claim 1, wherein the cationic modifier in the step 1) is DMSO and/or tributylphosphine containing a long carbon chain.

3. The method for preparing the graphene modified PET blended fiber according to claim 1, wherein in the step 2), the modifier is one or more of cetyl trimethyl ammonium bromide, sodium dodecyl sulfate, ethylenediamine and polyvinylpyrrolidone.

4. The preparation method of the graphene modified PET blended fiber according to claim 1, wherein in the step 2), the modified cationic graphene accounts for 1% -5%, the PET slice powder accounts for 95% -98.9%, and the modifier accounts for 0.1% -1%.

5. The preparation method of the graphene modified PET blended fiber according to claim 1, wherein two components in the blended fiber in the step 4) are of a skin-core structure, and the two components comprise a middle PET spun yarn (A) and a peripheral graphene modified spun yarn (B) which are arranged at intervals.

6. The preparation method of the graphene modified PET blended fiber according to claim 1 or 5, wherein the cross section of the blended fiber is clover-shaped.

7. The preparation method of the graphene-modified PET blended fiber according to claim 1, wherein the intrinsic viscosity of the PET slices is 0.65 +/-0.2 dL/g, and the melting point is 240-265 ℃.

8. The preparation method of the graphene modified PET blended fiber according to claim 1, wherein when a twin-screw extruder is used for melt granulation in the step 3), the temperatures of the first zone to the fifth zone of the screw are 245-255 ℃, 260-270 ℃, 265-275 ℃ and 260-270 ℃.

9. The preparation method of the graphene modified PET blended fiber according to claim 1, wherein in the step 4), the mass ratio of the graphene modified slice to the PET slice is 20:80-40: 60; the screw temperature of the two-component composite spinning assembly is 280-310 ℃, and the box body temperature of the two-component composite spinning assembly is 275-295 ℃.

10. The preparation method of the graphene modified PET blended fiber according to claim 1, wherein the temperature of the first hot roller is 70-90 ℃, the temperature of the second hot roller is 130-180 ℃, and the stretching ratio is 3.0-4.0 during stretching and setting in the step 5).

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