WO2023116210A1

WO2023116210A1 - Method for preparing poy/fdy polyester-polyester composite yarn

Info

Publication number: WO2023116210A1
Application number: PCT/CN2022/129149
Authority: WO
Inventors: 王雪; 王丽丽; 王相明; 汤方明; 孙晓华; 宋戈; 杨超明; 陈锋; 寇婉婷; 沈丽
Original assignee: 江苏恒力化纤股份有限公司
Priority date: 2021-12-24
Filing date: 2022-11-02
Publication date: 2023-06-29
Also published as: CN114232161A

Abstract

A method for preparing a POY/FDY polyester-polyester composite yarn, in which polyester POY and polyester FDY are combined and then wound to form a POY/FDY polyester-polyester composite yarn. Before the polyester POY is combined with the polyester FDY, the polyester POY is sequentially subjected to the processes of cooling, oiling, yarn guiding, and pre-interlacing; a yarn guide roller (4) used during the yarn guide process is arranged below an oiling position (3), and the height difference between the yarn guide roller and the oiling position (3) is 20-30 mm; a spinneret is located above the oiling position (3), and the height difference between the spinneret and the oiling position (3) is 90-110 mm; a pre-interlacing device (5) used in the pre-interlacing process is located below the yarn guide roller (4), and the height difference between the pre-interlacing device (5) and the yarn guide roller (4) is 3500-3600 mm. The yarn guide roller (4) is additionally provided behind the oiling position, thereby effectively adjusting the POY spinning tension; and the boiling water shrinkage of a product POY/FDY polyester-polyester composite yarn is 45.0±5.0%, such that the product POY/FDY polyester-polyester composite yarn can be widely used for wool-like, silk-like and high-quality knitted fabrics.

Description

A kind of preparation method of POY/FDY polyester composite yarn

technical field

The invention belongs to the technical field of polyester fibers, and relates to a preparation method of POY/FDY polyester composite yarn.

Background technique

Polyester fiber is currently the largest and most widely used synthetic fiber variety in the world. It is widely used in textiles such as clothing, bedding, various decorative fabrics, special fabrics for national defense and military industries, and other industrial fiber products. The production capacity of polyester series products in my country is growing at an alarming rate, and the rapid growth of polyester fiber production capacity has made China gradually develop into an important processing base for polyester products in the world. In recent years, with the development of international textile fabrics in the direction of thin, high-density, environmentally friendly functionality, and low-fiber composites, the upgrading of fiber raw materials has been continuously promoted, and the market demand for differentiated fibers has grown rapidly. Among them, different shrinkage mixed fiber yarn is one of the most commonly used differentiated fiber varieties. It has the characteristics of flexible raw material combination, unique fabric style, and low production cost. Used in combination, it is an ideal raw material for developing new high-grade chemical fiber fabrics. The annual output of mixed fiber yarn in my country has reached about 10,000 tons, and its leading variety is polyester different shrinkage mixed fiber yarn. Polyester different-shrinkage mixed fiber yarn is made of polyester POY and FDY and combined through the network. During dyeing and finishing, the thermal shrinkage rates of the two fibers are different, and the filament with a large shrinkage rate forms the core yarn of the mixed fiber yarn. Filaments with low shrinkage will form spiral crimps on the surface of blended filaments, giving the yarn a fluffy and soft feel, and are widely used in wool-like, silk-like and high-grade knitted fabrics.

The high-speed spinning blended fiber one-step process has the advantages of high production efficiency, short process, low consumption, fixed length and fixed weight, and can produce fine denier and ultrafine denier products, etc. It is suitable for processing high-grade fabrics. Therefore, the use of high-speed spinning mixed fiber one-step process is an inevitable trend in the development of different shrinkage mixed fiber technology in the future, and it is also an inevitable choice to improve the added value of my country's textiles and the competitiveness of the international market. However, in the development process of one-step spinning technology, there are still technical bottlenecks such as synchronous spinning and low shrinkage in boiling water, which lead to difficulties in regulating the structure of fiber aggregation, unstable shrinkage index, and low weaving processing efficiency.

Therefore, it is necessary to study a preparation method of POY/FDY polyester composite yarn that can effectively improve the boiling water shrinkage while maintaining the breaking strength and elongation at break, so as to realize the industrial production and production of one-step different shrinkage mixed fiber yarn. Application in high-grade chemical fiber fabrics.

Contents of the invention

The purpose of the present invention is to solve the above-mentioned problems existing in the prior art, and to provide a preparation method of POY/FDY polyester composite yarn.

In order to achieve the above object, the technical scheme adopted in the present invention is as follows:

A preparation method of POY/FDY polyester-polyester composite yarn, the polyester POY yarn and polyester FDY yarn are compounded and wound to form POY/FDY polyester-polyester composite yarn;

The speed of polyester POY yarn is 1660～1680m/min when it is jointed with polyester FDY yarn;

Before the polyester POY yarn is combined with the polyester FDY yarn, it goes through the processes of cooling, oiling, wire guiding and pre-network in sequence;

The godet roller used in the wire guide process is set below the oiling position, and the height difference from the oiling position (the distance between the highest point of the guiding wire roller and the oiling position in the vertical direction) is 20-30mm (the guide wire The position of the roller, on the one hand, takes into account the ease of installation and the available space, and on the other hand, a certain tension is generated between the godet roller and the winding. The larger the distance between the godet roller and the winding device, the greater the tension Considering that in the actual production device, due to the limited space distance, it is most suitable to set the godet roller 20-30mm below the oiling position), the spinneret is located above the oiling position, and the distance between the spinneret and the oiling position The height difference is 90-110mm, the pre-internet used in the pre-internet process is located below the godet roller, and the height difference between the pre-internet and the godet is 3500-3600mm;

The breaking strength of POY/FDY polyester composite yarn is 2.2-2.5cN/dtex, the breaking elongation is 30.0±3.0%, and the boiling water shrinkage is 45.0±5.0%. Boiling water shrinkage is closely related to breaking strength and breaking elongation. Usually, high breaking strength and low boiling water shrinkage; high breaking elongation and large boiling water shrinkage. The POY/FDY polyester composite yarn in the prior art has a breaking strength of 2.2cN/dtex, and when the breaking elongation is 42%, the boiling water shrinkage is about 30%. When the product is the best, the breaking strength is 1.91cN/dtex. dtex, when the elongation at break is 38%, the boiling water shrinkage rate is 40%; for the POY filament part of the present invention, a godet roller is added at a position of 110-140mm below the spinneret, and finally the obtained The breaking strength of POY/FDY polyester/polyester composite yarn is 2.2～2.5cN/dtex, the breaking elongation is 30.0±3.0%, and the boiling water shrinkage is 45.0±5.0%. Boiling water shrinkage has been effectively improved.

As a preferred technical solution:

According to the preparation method of POY/FDY polyester composite yarn as mentioned above, before the polyester FDY yarn is plyed with the polyester POY yarn, it undergoes the processes of cooling, oiling, pre-internetting and the first heating roller GR1 in sequence.

A kind of preparation method of POY/FDY polyester composite yarn as mentioned above, after polyester POY yarn and polyester FDY yarn are plied in godet SR1 to form composite yarn, pass through second hot roller GR2 successively (using GR1 and GR2 Speed difference for stretching) and the process of the main network, and then enter the winding device for winding molding to obtain POY/FDY polyester composite yarn.

According to the above-mentioned preparation method of POY/FDY polyester composite yarn, the output of polyester POY yarn and polyester FDY yarn is independently controlled by respective melt metering pumps.

A kind of preparation method of POY/FDY polyester composite yarn as mentioned above, the diameter of godet roller is 20～30mm, and the number of circles that tow is wound on godet roller is 1～2 (number of circles is 1～2 Mainly to control the tension, too much will lead to excessive tension).

According to the preparation method of POY/FDY polyester composite yarn as described above, the monofilament fineness of the polyester POY yarn is 1-1.5 dtex, and the monofilament fineness of the polyester FDY yarn is 1-1.5 dtex.

A kind of preparation method of POY/FDY polyester composite yarn as mentioned above, the fineness of POY/FDY polyester composite filament is 100～120dtex, the fineness ratio of FDY silk and POY silk in POY/FDY polyester composite yarn is 2～ 3:3～5 (The setting of the fineness ratio is mainly to consider the effect of the product, often POY silk has a large fineness).

A kind of preparation method of POY/FDY polyester composite yarn as mentioned above, the preparation process parameter of POY/FDY polyester composite yarn is: spinning temperature 285～295 ℃, cooling temperature 18～22 ℃ (POY silk and FDY silk It is the filaments extruded from the same melt, the spinning temperature and cooling temperature of POY filaments and FDY filaments are the same), the pre-network pressure is 0.30-0.60bar (the pre-network pressures of POY and FDY are both in this range, and the tension of POY is small , the pre-network pressure is lower than FDY), the joint network pressure is 0.80-2.00bar, the main network pressure is 3.50-4.50bar, the GR1 speed is 870-890m/min, and the SR1 speed (that is, the speed of polyester POY yarn when it is jointed with polyester FDY yarn) 1660～1680m/min, GR2 speed 3020～3030m/min, GR1 temperature 90～110℃, GR2 temperature 23～25℃, winding speed 3000～4000m/min; GR1 temperature 90～110℃, greater than the vitrification of polyester The temperature provides conditions for stretching; the temperature of GR2 is 23-25°C, which is heat setting at room temperature, in order to increase the shrinkage rate of boiling water; the speed of GR1 is 870-890m/min, and the speed of GR2 is 3020-3030m/min, and the speed of the two is used The difference provides the draw ratio of the FDY.

A method for preparing POY/FDY polyester-polyester composite yarn as described above, the breaking strength CV value of POY/FDY polyester-polyester composite yarn is ≤1.50%, the elongation at break CV value is ≤3.00%, and the evenness CV value is ≤1.50 %, the degree of network is 13-20 pieces/m.

Invention Mechanism:

Usually, fibers with boiling water shrinkage of about 20% are called general shrinkage fibers, and fibers with boiling water shrinkage of 35% to 45% are called high shrinkage fibers. Making high-shrinkage fibers and other types of yarns into blended yarns or twisted yarns will make the yarns have a special style and can be used to develop new fabric products.

In physical modification, it is generally through changing the spinning drawing and setting process in order to achieve high shrinkage. For example, the conventional POY yarn can be stretched at low temperature, set at low temperature or unshaped, etc., which can significantly increase the boiling water shrinkage. The boiling water shrinkage of POY/FDY polyester composite yarn is mainly determined by the performance of POY yarn. For POY yarn alone, when the spinning speed is 2500-3500m/min, the boiling water shrinkage of the fiber is the largest. But for POY/FDY polyester-polyester composite yarn, when POY yarn is composited with FDY through godet SR1, due to technological constraints, the tow cannot reach the optimal speed of 2500-3500m/min, resulting in POY/FDY polyester-polyester composite yarn The boiling water shrinkage of the silk is low (because the FDY silk needs to be stretched in the spinning process, and it needs to reach a certain draw ratio, if the draw ratio is too low, the quality of the FDY yarn such as strength, elongation, boiling water shrinkage, etc. cannot be achieved. Therefore, it is necessary to form a speed difference between the first hot roller and the second hot roller, and the speed of SR1 is between the two, and at the same time, POY and FDY are compounded here, and the tension of POY is less than that of FDY, and POY passes through SR1 A certain speed difference is required to control the stability of the tension between the second hot roller, which restricts the further increase of the speed of SR1 to reach the ideal speed).

The present invention is based on the POY/FDY composite spinning process in the prior art. For the POY filament part, a godet roller is added at a position 110-140 mm above the spinneret.

The distribution of force on the spinning process (referring to the process of the filament bundle from the spinneret to the winding) is one of the important factors in the melt spinning forming process, which is related to the spinning process conditions. The tension on the spinning process mainly includes rheological resistance, inertial force, and air friction. When the spinning speed is low, such as less than 2000m/min, due to the small inertial force and air frictional resistance, the filament tension is controlled by the rheological resistance, and the rheological resistance only slowly increases with the increase of spinning speed. Increased, but the overall tension is less. When the godet roll is added to the spinning process, the tension on the wire bundle from the godet roll to the godet SR1 changes, because there is a certain speed difference between the godet roll and the wire bundle on the godet SR1 (due to The godet roller is fixed, after the godet roller, due to the existence of a certain stretch, the speed is gradually increasing; at the same time, the tow has friction when passing through the godet roller, which will cause a speed difference), the tension on the tow There will be a certain amount of increase. The increase in tension is equivalent to increasing the spinning speed of POY filaments (as the spinning speed increases, the corresponding tension increases, which can be considered as an equivalent principle here). Within a certain range of tension increase, POY/FDY polyester-polyester composite yarn can obtain Larger boiling water shrinkage.

In the present invention, when the shrinkage in boiling water is increased to 45.0±5.0%, the breaking strength of polyester-polyester composite yarn is 2.2～2.5cN/dtex, and the elongation at break is 30.0±3.0%. The elongation rate does not change greatly due to the change of boiling water shrinkage rate, but is stable in a certain range, which can meet the requirements of taking. The reason is that the FDY part of the polyester-polyester composite yarn has a greater weight on the breaking strength and elongation at break, and the change of POY boiling water shrinkage has little effect on the breaking strength and elongation at break.

Beneficial effect:

(1) The present invention adds a godet roller behind the oiling position, effectively regulates the POY spinning tension, and the boiling water shrinkage rate of the product POY/FDY polyester-polyester composite yarn is 45.0 ± 5.0%;

(2) The heat shrinkage ratios of the two fibers in the prepared composite yarn of the present invention are different, and the long filaments with a large shrinkage ratio form the core filament of the mixed fiber yarn, and the small filaments with a shrinkage ratio can form helical crimps on the surface layer of the mixed fiber yarn , so that the yarn has a fluffy and soft feel, and is widely used in wool-like, silk-like and high-grade knitted fabrics.

Description of drawings

Fig. 1 is a preparation process flow chart of the present invention;

Among them, 1-POY spinneret, 2-FDY spinneret, 3-oiling position, 4- godet roller, 5- pre-networker, 6- godet SR1, 7- first heat roller GR1, 8 -Second heat roll GR2, 9-ply networker, 10-main networker, 11-winding device.

Detailed ways

The present invention will be further described below in combination with specific embodiments. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art may make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

Example 1

As shown in Figure 1, a preparation method of POY/FDY polyester composite yarn, the polyester POY yarn with a monofilament fineness of 1dtex undergoes the processes of cooling, oiling, guide wire and pre-network successively, and the polyester with a monofilament fineness of 1dtex After the FDY yarns are cooled, oiled, pre-internetted, and the first hot roller GR1 7 in sequence, the polyester POY yarns and polyester FDY yarns are plied in the godet SR1 6 to form a composite yarn bundle, and the composite yarn Make a network on the beam, and pass through the operation of the second hot roller GR2 8 and the main network (the main network device used in the main network process is 10 in the figure) successively, then enter the winding device 11, and carry out winding molding to obtain POY /FDY polyester composite yarn; wherein, the output of polyester POY yarn and polyester FDY yarn is controlled separately by their respective melt metering pumps; the godet roller 4 used in the godet process is set below the oiling position 3, and is connected with the upper The height difference of the oiling position is 20mm, the spinneret (POY spinneret 1 and FDY spinneret 2) is located above the oiling position, and the height difference between the spinneret and the oiling position is 90mm, the pre-network process used The pre-internet 5 is located below the godet, and the height difference between the pre-internet and the godet is 3500 mm; the diameter of the godet is 20 mm, and the tow is wound on the godet for 1 turn;

Process parameters are: spinning temperature 285°C, cooling temperature 18°C, pre-network pressure 0.3bar, joint network pressure 0.8bar, main network pressure 3.5bar, GR1 speed 870m/min, SR1 speed 1660m/min, GR2 speed 3020m/min , GR1 temperature 90°C, GR2 temperature 23°C, winding speed 3000m/min.

The fineness of the finally obtained POY/FDY polyester-polyester composite yarn is 120dtex, and the fineness ratio of FDY filament and POY filament in the POY/FDY polyester-polyester composite filament is 3:4; the boiling water shrinkage rate of the polyester-polyester composite filament is 43%. The strength is 2.3cN/dtex, the elongation at break is 29%, the CV value of breaking strength is 1.5%, the CV value of elongation at break is 2.9%, the CV value of evenness is 1.5%, and the network degree is 13 pieces/m.

Comparative example 1

A preparation method of POY/FDY polyester composite yarn, which is basically the same as in Example 1, the difference is that before the polyester POY yarn and the polyester FDY yarn are plied together, the polyester POY yarn does not go through the process of guiding the yarn, and directly enters the pre-filtering process after being oiled. In the process of network, the fineness of the final POY/FDY polyester composite yarn is 120dtex, and the fineness ratio of FDY filament and POY filament in POY/FDY polyester composite filament is 3:4; the boiling water shrinkage ratio of polyester composite filament is 18%, the breaking strength is 2.3cN/dtex, the breaking elongation is 30%, the breaking strength CV value is 1.2%, the breaking elongation CV value is 2.9%, the evenness CV value is 1.4%, and the network degree is 17% a/m.

Comparing Example 1 with Comparative Example 1, it can be seen that the boiling water shrinkage of Example 1 is significantly higher than that of Comparative Example 1, because compared with Comparative Example 1, the increase of the godet roll in Example 1 makes the tow The tension on the surface has increased, and the increase in tension is equivalent to increasing the spinning speed of POY filaments (the spinning speed increases, and the corresponding tension increases, which can be considered as the equivalent principle here). Within a certain range of tension increase, POY /FDY polyester composite yarn obtains a larger shrinkage in boiling water.

Example 2

A preparation method of POY/FDY polyester composite yarn, the polyester POY yarn with a monofilament fineness of 1.2dtex goes through the processes of cooling, oiling, guide wire and pre-network successively, and the polyester FDY yarn with a monofilament fineness of 1.2dtex goes through successively After the processes of cooling, oiling, pre-internetting and the first hot roller GR1, polyester POY yarns and polyester FDY yarns are plied in the godet SR1 to form composite tows, and the composite tows are networked on the composite tows with a ply networker, and sequentially After the process of the second hot roller GR2 and the main network, it enters the winding device for winding and forming to obtain POY/FDY polyester composite filaments; wherein, the output of polyester POY filaments and polyester FDY filaments is determined by their respective melts The metering pump is controlled separately; the godet roller used in the guide wire process is set below the oiling position, and the height difference from the oiling position is 25mm, the spinneret is located above the oiling position, and the spinneret and the oiling position The height difference is 95mm, the pre-internet device used in the pre-internet process is located under the godet roller, and the height difference between the pre-internet device and the godet roller is 3500mm; the diameter of the godet roller is 20mm, and the tow is on the godet roller Winding 1 turn;

Process parameters are: spinning temperature 285°C, cooling temperature 20°C, pre-network pressure 0.3bar, joint network pressure 0.8bar, main network pressure 3.6bar, GR1 speed 875m/min, SR1 speed 1668m/min, GR2 speed 3020m/min , GR1 temperature is 95°C, GR2 temperature is 24°C, winding speed is 3150m/min.

The fineness of the finally obtained POY/FDY polyester composite yarn is 105dtex, and the fineness ratio of FDY filament and POY filament in the POY/FDY polyester composite filament is 2:3; the boiling water shrinkage rate of the polyester composite filament is 45%. The strength is 2.4cN/dtex, the elongation at break is 30%, the CV value of the breaking strength is 1.4%, the CV value of the elongation at break is 3.0%, the CV value of the evenness is 1.4%, and the network degree is 20 pieces/m.

Example 3

A preparation method of POY/FDY polyester composite yarn, the polyester POY yarn with a monofilament fineness of 1.2dtex goes through the processes of cooling, oiling, guide wire and pre-network successively, and the polyester FDY yarn with a monofilament fineness of 1.2dtex goes through successively After the processes of cooling, oiling, pre-internetting and the first hot roller GR1, polyester POY yarns and polyester FDY yarns are plied in the godet SR1 to form composite tows, and the composite tows are networked on the composite tows with a ply networker, and sequentially After the process of the second hot roller GR2 and the main network, it enters the winding device for winding and forming to obtain POY/FDY polyester composite filaments; wherein, the output of polyester POY filaments and polyester FDY filaments is determined by their respective melts The metering pump is controlled separately; the godet roller used in the guide wire process is set below the oiling position, and the height difference from the oiling position is 25mm, the spinneret is located above the oiling position, and the spinneret and the oiling position The height difference is 102mm, the pre-internet used in the pre-internet process is located below the godet roller, and the height difference between the pre-internet and the godet roller is 3550mm; the diameter of the godet roller is 30mm, and the tow is on the godet roller Wind 2 turns;

Process parameters are: spinning temperature 290°C, cooling temperature 20°C, pre-network pressure 0.4bar, joint network pressure 1.2bar, main network pressure 3.8bar, GR1 speed 880m/min, SR1 speed 1670m/min, GR2 speed 3025m/min , GR1 temperature 100°C, GR2 temperature 25°C, winding speed 3380m/min.

The fineness of the finally obtained POY/FDY polyester composite yarn is 105dtex, and the fineness ratio of FDY filament and POY filament in the POY/FDY polyester composite filament is 3:5; the boiling water shrinkage rate of the polyester composite filament is 44%. The strength is 2.3cN/dtex, the elongation at break is 28%, the CV value of breaking strength is 1.4%, the CV value of elongation at break is 2.6%, the CV value of evenness is 1.3%, and the network degree is 20 pieces/m.

Example 4

A preparation method of POY/FDY polyester composite yarn, the polyester POY yarn with a monofilament fineness of 1.5dtex undergoes the processes of cooling, oiling, guide wire and pre-network successively, and the polyester FDY yarn with a monofilament fineness of 1.5dtex sequentially passes through After the processes of cooling, oiling, pre-internetting and the first hot roller GR1, polyester POY yarns and polyester FDY yarns are plied in the godet SR1 to form composite tows, and the composite tows are networked on the composite tows with a ply networker, and sequentially After the process of the second hot roller GR2 and the main network, it enters the winding device for winding and forming to obtain POY/FDY polyester composite filaments; wherein, the output of polyester POY filaments and polyester FDY filaments is determined by their respective melts The metering pump is controlled separately; before the polyester POY yarn is jointed with the polyester FDY yarn, it goes through the processes of cooling, oiling, wire guiding and pre-netting in sequence; The process of netting, stretching and shaping; the godet roll used in the guide wire process is set below the oiling position, and the height difference from the oiling position is 30mm, the spinneret is located above the oiling position, and the spinneret The height difference from the oiling position is 108mm, the pre-internet used in the pre-internet process is located below the godet roller, and the height difference between the pre-internet and the godet roller is 3600mm; the diameter of the godet roller is 25mm, and the tow is in Wrap 2 turns on the godet roller;

Process parameters are: spinning temperature 290°C, cooling temperature 22°C, pre-network pressure 0.5bar, joint network pressure 1.5bar, main network pressure 4.2bar, GR1 speed 890m/min, SR1 speed 1676m/min, GR2 speed 3030m/min , GR1 temperature 105°C, GR2 temperature 25°C, winding speed 3670m/min.

The fineness of the finally obtained POY/FDY polyester composite yarn is 120dtex, and the fineness ratio of FDY filament and POY filament in the POY/FDY polyester composite filament is 3:3; the boiling water shrinkage rate of the polyester composite filament is 40%. The strength is 2.5cN/dtex, the elongation at break is 27%, the CV value of breaking strength is 1.3%, the CV value of elongation at break is 2.8%, the CV value of evenness is 1.3%, and the network degree is 17 pieces/m.

Example 5

A preparation method of POY/FDY polyester composite yarn, the polyester POY yarn with a monofilament fineness of 1.5dtex undergoes the processes of cooling, oiling, guide wire and pre-network successively, and the polyester FDY yarn with a monofilament fineness of 1.5dtex sequentially passes through After the processes of cooling, oiling, pre-internetting and the first hot roller GR1, polyester POY yarns and polyester FDY yarns are plied in the godet SR1 to form composite tows, and the composite tows are networked on the composite tows with a ply networker, and sequentially After the process of the second hot roller GR2 and the main network, it enters the winding device for winding and forming to obtain POY/FDY polyester composite filaments; wherein, the output of polyester POY filaments and polyester FDY filaments is determined by their respective melts The metering pump is controlled separately; before the polyester POY yarn is jointed with the polyester FDY yarn, it goes through the processes of cooling, oiling, wire guiding and pre-netting in sequence; The process of netting, stretching and shaping; the godet roll used in the guide wire process is set below the oiling position, and the height difference from the oiling position is 30mm, the spinneret is located above the oiling position, and the spinneret The height difference from the oiling position is 110mm, the pre-internet used in the pre-internetting process is located below the godet roller, and the height difference between the pre-internet and the godet roller is 3600mm; the diameter of the godet is 25mm, and the tow is in Wrap 2 turns on the godet roller;

The process parameters are: spinning temperature 295°C, cooling temperature 22°C, pre-network pressure 0.6bar, joint network pressure 2bar, main network pressure 4.5bar, GR1 speed 890m/min, SR1 speed 1680m/min, GR2 speed 3030m/min, The temperature of GR1 is 110°C, the temperature of GR2 is 25°C, and the winding speed is 4000m/min.

The fineness of the finally obtained POY/FDY polyester composite yarn is 120dtex, and the fineness ratio of FDY filament and POY filament in the POY/FDY polyester composite filament is 2:5; the boiling water shrinkage rate of the polyester composite filament is 50%. The strength is 2.2cN/dtex, the elongation at break is 33%, the CV value of breaking strength is 1.4%, the CV value of elongation at break is 3.0%, the CV value of evenness is 1.5%, and the network degree is 16 pieces/m.

Claims

A preparation method of POY/FDY polyester composite yarn, polyester POY yarn and polyester FDY yarn are plied and then wound to form POY/FDY polyester polyester composite yarn; the speed of polyester POY yarn and polyester FDY yarn is 1660 ～1680m/min, characterized in that: before the polyester POY yarn is combined with the polyester FDY yarn, it undergoes the processes of cooling, oiling, wire guiding and pre-network in sequence;

The godet roller used in the guide wire process is set below the oiling position, and the height difference from the oiling position is 20 to 30 mm, and the spinneret is located above the oiling position, and the height difference between the spinneret and the oiling position is 90-110mm, the pre-internet used in the pre-internet process is located below the godet roller, and the height difference between the pre-internet and the godet is 3500-3600mm;

The breaking strength of POY/FDY polyester composite yarn is 2.2-2.5cN/dtex, the breaking elongation is 30.0±3.0%, and the boiling water shrinkage is 45.0±5.0%.
A method for preparing POY/FDY polyester composite yarn according to claim 1, wherein the polyester FDY yarn is sequentially cooled, oiled, pre-internetted and first heated roller GR1 before plying with the polyester POY yarn process.
The preparation method of a kind of POY/FDY polyester composite yarn according to claim 2 is characterized in that, after the polyester POY yarn and the polyester FDY yarn are plied in the godet SR1 to form a composite yarn bundle, they pass through the second hot roller successively The process of GR2 and the main network, then enters the winding device for winding and forming, and obtains POY/FDY polyester-polyester composite yarn.
The preparation method of a kind of POY/FDY polyester composite yarn according to claim 1, characterized in that, the output of polyester POY yarn and polyester FDY yarn is controlled independently by respective melt metering pumps.
A method for preparing POY/FDY polyester composite yarn according to claim 1, wherein the diameter of the godet roll is 20-30 mm, and the number of turns of the tow on the godet roll is 1-2 .
The preparation method of a POY/FDY polyester composite yarn according to claim 1, characterized in that the monofilament fineness of the polyester POY yarn is 1-1.5 dtex, and the monofilament fineness of the polyester FDY yarn is 1-1.5 dtex.
A method for preparing POY/FDY polyester composite yarn according to claim 6, characterized in that the fineness of POY/FDY polyester composite yarn is 100-120dtex, and the POY/FDY polyester composite yarn includes FDY silk and POY The fineness ratio of silk is 2~3:3~5.
A method for preparing POY/FDY polyester composite yarn according to claim 7, characterized in that the preparation process parameters of POY/FDY polyester composite yarn are: spinning temperature 285-295°C, cooling temperature 18-22 ℃, pre-network pressure 0.30~0.60bar, joint network pressure 0.80~2.00bar, main network pressure 3.50~4.50bar, GR1 speed 870~890m/min, GR2 speed 3020~3030m/min, GR1 temperature 90~110℃, GR2 The temperature is 23-25°C, and the winding speed is 3000-4000m/min.
A method for preparing POY/FDY polyester-polyester composite yarn according to claim 8, characterized in that, the breaking strength CV value of POY/FDY polyester-polyester composite yarn is ≤1.50%, and the breaking elongation CV value is ≤3.00%. The dry uniformity CV value is ≤1.50%, and the network degree is 13-20 pieces/m.