High-shrinkage polyester fiber and production method thereof
By introducing a heat exchange jacket and a static mixer into the spinning box, combined with a low-temperature tensile process, the problem of rapid rise in component pressure and insufficient boiling water shrinkage in the production of high-shrinkage polyester fibers is solved, and high-shrinkage fibers are achieved efficiently.
Patent Information
- Application Number
- CN202510414570.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-03
- Publication Date
- 2025-08-15
AI Technical Summary
In the existing high-shrinkage polyester fiber production technology, the sliced spinning route causes the spinning module to rise rapidly, the component replacement cycle is short, and the melt direct spinning route cannot adjust the boiling water shrinkage rate, and the physically modified fibers have insufficient boiling water shrinkage rate, which cannot meet market demand.
Add heat exchange jackets and static mixers to the spinning box to improve the temperature and mixing uniformity of high viscosity melt, combine the low-temperature stretching process to optimize the spacing and speed of the heat rollers to ensure the boiling water shrinkage rate and physical index uniformity of the fibers.
The replacement cycle of spinning components is improved, the floating wire and broken ends are reduced, the spinability and physical index uniformity of fibers are increased, and the boiling water shrinkage rate reaches 30-35%, meeting market demand.
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Figure CN120485967A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of high-shrinkage fibers and relates to a high-shrinkage polyester fiber and a production method thereof. Background Art
[0002] High shrinkage fiber is a chemical fiber with a boiling water shrinkage rate higher than 15%. Under heating conditions, it can shrink rapidly to form a fabric with concave and convex patterns, which has the characteristics of strong three-dimensional sense and soft feel.
[0003] Currently, high-shrinkage polyester fibers are generally produced through physical or chemical modification. Chemical modification can be achieved through two production routes: melt spinning and chip spinning. The melt spinning route involves adding a copolymer component during the polymerization reaction to reduce the crystallization rate and degree of crystallinity, thereby achieving the desired high-shrinkage polyester properties. However, due to the relatively low market demand for high-shrinkage polyester fibers, the melt spinning route involves adding the copolymer online during the polymerization process, making it impossible to reduce the boiling water shrinkage through the spinning process. This results in a high production volume of high-shrinkage polyester fibers that cannot be absorbed by the market.
[0004] In contrast, the chip spinning route uses high-shrinkage polyester chips injected through a screw. Although the output is controllable, the production cost is relatively high. In addition, when using high-shrinkage polyester chips for production, due to the relatively high viscosity of the high-shrinkage polyester chips, the high-viscosity melt is prone to agglomeration after entering the spinning component. In addition, there are more ash and agglomerated particles in the high-shrinkage polyester chips, which not only causes the pressure of the spinning component to rise faster, but also shortens the component replacement cycle.
[0005] Physical modification to produce high-shrinkage polyester fibers involves low-temperature, low-ratio stretching to give the fibers proper orientation and reduce crystallization. However, the boiling water shrinkage of the high-shrinkage polyester fibers produced by this process is only about 20% at most, which cannot meet the market requirement of a boiling water shrinkage of 30%.
[0006] Reference 1 (Development of 55dtex / 24f High Shrinkage Polyester Direct-Spun FDY [J]. Synthetic Fiber Industry. 2005, 28(2):59-61) sets the setting temperature to 70°C and the drafting ratio to 2.82, resulting in a boiling water shrinkage of 13-20% for the produced fiber, which does not meet market demand. Reference 2 (Application and Discussion of High Shrinkage Fully-Drawn Polyester Yarn [J]. Synthetic Fiber. 2005, (9):31-39) uses a chip spinning route to produce high shrinkage fully-drawn yarn. By reducing the melt pressure extruded by the screw injection device to 8-9 MPa, the problem of excessive ash and agglomerated particles in the high shrinkage chips leading to a short service life of the components and filters is solved. However, due to its relatively high viscosity, using too low a melt pressure can easily lead to problems such as thin linear density, injection head yarn, floating yarn, and broken yarn.
[0007] Therefore, it is of great significance to study a high shrinkage polyester fiber and a production method thereof to solve the problems existing in the prior art. Summary of the Invention
[0008] The purpose of the present invention is to solve the problems existing in the prior art and provide a high-shrinkage polyester fiber and a production method thereof.
[0009] In order to achieve the above object, the technical solution adopted by the present invention is as follows:
[0010] A method for producing high-shrinkage polyester fiber comprises the following steps: adding high-shrinkage polyester chips to a conventional polyester melt through a screw injection device to obtain a mixed melt; the mixed melt, after melt conveying and melt distribution, enters a spinning manifold; and after melt spinning, sequentially undergoes cooling, first oiling, first pre-internetting, GR1 godet roller, HR2 hot roller, HR3 hot roller, HR4 hot roller, HR5 hot roller, GR6 godet roller, second oiling, second pre-internetting, main internetting, GR7 godet roller, and winding to produce the high-shrinkage polyester fiber.
[0011] The intrinsic viscosity of the high shrinkage polyester chips is 0.68-0.78 dL / g, and the addition amount of the high shrinkage polyester chips is 14-16 wt% of the mixed melt;
[0012] The intrinsic viscosity of conventional polyester melt is 0.620-0.630 dL / g;
[0013] A metering pump base is provided on the upper surface of the spinning manifold, and the metering pump is installed above the metering pump base. A plurality of melt diversion pipes are provided in the spinning manifold, and the plurality of melt diversion pipes are connected to the metering pump base. Each melt diversion pipe is wrapped by a heat exchange jacket, and each melt diversion pipe is respectively connected to the input end of a static mixer, and the output end of the static mixer is connected to the spinning assembly. The output end of the static mixer can be connected to one spinning assembly or to multiple spinning assemblies.
[0014] The heat exchange jacket is used to heat the temperature of the melt in the melt diversion pipe to 290-292°C;
[0015] When the replacement cycle of the spinneret assembly is 45 days, the pressure rise of the spinneret assembly is ≤2.0MPa, the proportion of floating fibers is ≤0.03%, and the breakage rate is ≤7%;
[0016] The present invention adds a heat exchange jacket and a static mixer between the spinning manifolds. The function of the heat exchange jacket is to heat the mixed melt, increase the temperature of the high-viscosity melt corresponding to the high-shrinkage polyester chips, and thus improve the fluidity of the mixed melt; the purpose of the static mixer is to improve the mixing uniformity of the high-viscosity polyester melt and the conventional polyester melt; through the cooperation of the two, the high-viscosity polyester melt will not produce agglomeration, solve the problem of rapid pressure increase of the component, thereby improving the component replacement cycle, and because the high-viscosity polyester melt will not produce agglomeration, the spinnability and physical index uniformity of the fiber are improved, thereby reducing the number of drifting fibers and broken ends; wherein, although increasing the temperature of the mixed melt will cause a decrease in viscosity, the distance between the spinning manifold and the spinneret is short, which will not cause a more obvious viscosity drop and will not have a negative impact on the performance of the fiber;
[0017] Although there is a combination scheme of a heat exchange jacket and a static mixer in the prior art, it is mainly installed on the melt pipe, which is completely different from the function of the present application. The main function of the heat exchange device of the prior art is to reduce the temperature of the polyester melt. This is because the polyester melt will produce a temperature rise and increase the viscosity drop after being pressurized by the booster pump. The function of the static mixer in the melt pipe is to solve the problem of uneven melt quality caused by the temperature gradient between the pipe wall and the center of the polyester melt conveying pipe. Although the technology of the prior art can also achieve a rapid increase in the melt temperature, increasing the temperature on the melt pipe will cause the melt to be transported at high temperature for a long time, resulting in excessive thermal degradation and inability to guarantee the viscosity of the melt filament.
[0018] As the preferred technical solution:
[0019] In the above-mentioned method for producing high-shrinkage polyester fibers, the melting point of the high-shrinkage polyester chips is 235-245°C.
[0020] In the above-mentioned method for producing high-shrinkage polyester fiber, the screw injection device is divided into five zones, the temperature of screw zone 1 is 258-260°C, the temperature of screw zone 2 is 268-270°C, the temperature of screw zone 3 is 270-272°C, the temperature of screw zone 4 is 270-272°C, and the temperature of screw zone 5 is 272-275°C.
[0021] The extrusion pressure of the screw injection device is 13-14MPa.
[0022] In the above-mentioned method for producing high-shrinkage polyester fibers, a heat medium tube and a heat medium return tube are provided in the spinning manifold, all heat exchange jackets are simultaneously connected to the heat medium tube and the heat medium return tube, the input ends of all heat exchange jackets are connected to the output ends of the heat medium tube, the output ends of all heat exchange jackets are connected to the input ends of the heat medium return tube, and the input ends of the heat medium tube and the output ends of the heat medium return tube are both connected to the heat medium station; wherein, the temperature of the heat medium introduced into the heat medium tube is 305-315°C.
[0023] As described above, a method for producing high-shrinkage polyester fiber includes a melt diversion tube including a melt diversion tube I, a melt diversion tube II, and 4 to 6 melt heat exchange tubes; the upper end of the melt diversion tube I is connected to the metering pump base via a melt diversion plate, the upper ends of the 4 to 6 melt heat exchange tubes are simultaneously connected to the lower end of the melt diversion tube I, the lower ends of the 4 to 6 melt heat exchange tubes are simultaneously connected to the upper end of the melt diversion tube II, and the lower end of the melt diversion tube II is connected to the input end of a static mixer; each heat exchange jacket simultaneously wraps around 4 to 6 melt heat exchange tubes; the melt in the melt diversion tube I is diverted by the 4 to 6 melt heat exchange tubes in the melt diversion tube, thereby increasing the heating area of the melt and raising the melt temperature more quickly.
[0024] In the above-mentioned method for producing high-shrinkage polyester fibers, the high-shrinkage polyester chips are first dried and then added to a screw injection device for mixing with a conventional polyester melt. The drying temperature is 160-165°C, the drying time is 10-12 hours, the dew point is -99--101°C, and the moisture content of the high-shrinkage polyester chips after drying is ≤50 ppm.
[0025] The above-mentioned method for producing high-shrinkage polyester fiber comprises the following process parameters: the temperature of the spinning manifold is 285-288°C; the temperature of the HR2 hot roller is 50-55°C; the temperature of the HR3 hot roller is 55-60°C; the distance between the HR2 hot roller and the HR3 hot roller is 4.8-5.2 cm; the temperature of the HR4 hot roller is 45-50°C; the temperature of the HR5 hot roller is 45-50°C; the distance between the HR3 hot roller and the HR4 hot roller is 4.8-5.2 cm; the HR2 hot roller, the HR3 hot roller and the HR4 hot roller are all smooth rollers with roughness of 0.1±0.02μm, 0.1±0.02μm and 0.1±0.02μm respectively; the yarn The contact lengths of the bundle with the HR2, HR3, and HR4 hot rollers are 60-65% of the circumferences of the HR2, HR3, and HR4 hot rollers, respectively. The speed of the GR1 godet is 1650±20 m / min; the speed of the HR2 godet is 1650±20 m / min; the speed of the HR3 godet is 1750±20 m / min; the speed of the HR4 godet is 4000±20 m / min; the speed of the HR5 godet is 4000±20 m / min; the speed of the GR6 godet is 4020±20 m / min; the speed of the GR7 godet is 4020±20 m / min; and the winding speed is 4020±20 m / min.
[0026] The spinning temperature is set within this range because the melting point of high shrinkage polyester chips is low, so the spinning temperature is lower than the temperature range of conventional setting values;
[0027] Since the lower the stretching temperature, the higher the boiling water shrinkage of the fiber, the temperature of the HR2 and HR3 hot rollers is relatively low. Specifically, the crystallinity of the mixed melt changes greatly. If the temperature of the HR2 and HR3 hot rollers is increased to above the glass transition temperature, the arrangement and orientation of the structural units inside the fiber will be better, resulting in an increase in crystallinity, thereby significantly reducing the boiling water shrinkage. If the temperature is too low, poor dyeing and lint problems caused by cold stretching are likely to occur. By reducing the temperature of the HR2 and HR3 hot rollers and the distance between the two rollers, the number of fiber lints can be minimized under high boiling water shrinkage conditions. Among them, the distance between the HR2 and HR3 hot rollers is reduced to 4.8-5.2 cm, which improves the continuity of the heating of the two hot rollers and ensures the continuity of the glass transition process. In addition, due to the use of a low-temperature heating stretching process, the production process using a 25 cm hot roller distance in the existing technology is prone to a long heating interval, resulting in a drop in fiber temperature and uneven glass transition, affecting dyeing uniformity and lint. Therefore, the distance between the HR2 and HR3 hot rollers is reduced to 4.8-5.2 cm.
[0028] The temperature of HR4 and HR5 hot rollers is 45-50℃. This is because the boiling water shrinkage rate is mainly affected by the setting temperature of HR4 and HR5 hot rollers. Although lowering the setting temperature can increase the boiling water shrinkage rate, if the HR4 and HR5 hot rollers are below 45℃, the yarn bundles are easily affected by the ambient temperature, especially the influence of the ambient temperature on each yarn bundle is inconsistent, which can easily lead to poor dyeing uniformity of the fiber.
[0029] The HR2, HR3, and HR4 hot rollers are all smooth rollers with roughnesses of 0.1±0.02μm, 0.1±0.02μm, and 0.1±0.02μm, respectively. The contact lengths between the filament bundle and the HR2, HR3, and HR4 hot rollers are 60-65% of the circumference of the HR2, HR3, and HR4 rollers, respectively. The surface roughness of the hot rollers can be characterized by the difference between the peaks and valleys of the surface protrusions. The roughness of the conventional HR2 and HR3 hot rollers is 0.20μm, and that of the HR4 hot roller is 1.5μm. The lower surface roughness of the HR2 and HR3 hot rollers increases the contact area between the filament bundle and the hot rollers, which can improve the yarn holding force. Combined with the set contact length, this increases the residence time of the filament bundle in the hot rollers, ensuring uniform fiber vitrification and stable dyeing properties at low temperatures for the HR2 and HR3 hot rollers.
[0030] In the existing technology, the distance between HR3 and HR4 is 25 cm. Narrowing the distance between HR3 and HR4 to 4.8-5.2 cm can greatly reduce the interference of the airflow around the hot roller on the yarn bundle and the sagging of the yarn bundle caused by gravity, making the stretching more stable.
[0031] The speeds of the GR1 godet roller, HR2 hot roller and HR3 hot roller are slightly lower than those of conventional fibers, mainly because the temperatures of the HR2 hot roller and HR3 hot roller are relatively low. By reducing the speed and increasing the contact area between the filament bundle and the hot roller, the heating time of the filament bundle on the hot roller can be increased, and the uniformity of the degree of vitrification can be increased, thereby ensuring that the dyeing uniformity and the number of hairy fibers are controlled at a lower stretching temperature.
[0032] The reason why the speed of HR4 and HR5 hot rollers is lower is to reduce the draft ratio, which can inhibit the increase of fiber crystallinity and increase boiling water shrinkage. However, if the draft ratio is too low, although the boiling water shrinkage can be improved, it will lead to low fiber breaking strength and high breaking elongation, which cannot meet the requirements of subsequent weaving.
[0033] The speed of GR6 and GR7 godet rollers is higher than that of HR4 and HR5 hot rollers, mainly to maintain the tension stability of the yarn bundle.
[0034] The winding speed is about 500 m / min lower than that of conventional fibers, mainly because the winding speed is related to the degree of orientation, which affects the boiling water shrinkage rate. The lower the winding speed, the higher the boiling water shrinkage rate. However, when the winding speed is too low, such as when it is lower than the speed of the GR6 godet roller and the GR7 godet roller, it is easy to cause unstable tension. Therefore, the winding speed of this application is consistent with the speed of the GR6 godet roller and the GR7 godet roller.
[0035] The present invention also provides a high-shrinkage polyester fiber produced by the production method as described above. The high-shrinkage polyester fiber has a breaking strength of ≥3.8 cN / dtex, an elongation at break of 30±2%, a boiling water shrinkage of 30-35%, and a dyeing uniformity (gray card) of ≥4.
[0036] Beneficial effects:
[0037] (1) The present invention provides a method for producing high-shrinkage polyester fibers, wherein a heat exchange jacket and a static mixer are added between the spinning manifolds. Through the cooperation of the two, the high-viscosity polyester melt does not agglomerate, thereby solving the problem of rapid pressure increase in the components and improving the component replacement cycle.
[0038] (2) The high shrinkage polyester fiber produced by the production method of the present invention has improved spinnability and uniformity of physical indicators, thereby reducing the number of floating fibers and broken ends; at the same time, the boiling water shrinkage rate can reach 30-35%. BRIEF DESCRIPTION OF THE DRAWINGS
[0039] Figure 1 This is a schematic diagram of the spinning box structure; the number of melt diversion pipes in the figure is only for reference and does not represent the actual situation;
[0040] Among them, 1-spinning box, 2-melt diversion pipe, 3-heat exchange jacket, 4-static mixer, 5-heat medium pipe, 6-heat medium return pipe, 7-melt diversion plate. DETAILED DESCRIPTION
[0041] Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiments are only used to illustrate the present invention and are not used in limiting the scope of the present invention.In addition, should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall equally within the scope limited by the appended claims of the application.
[0042] The test methods involved in the performance indicators in the embodiments and comparative examples of the present invention are as follows:
[0043] Breaking strength and elongation at break: Referring to GB / T 14344-2022 "Test method for tensile properties of chemical fiber filaments", a fully automatic single yarn strength tester (model YG023B-Ⅱ) was used to measure the polyester fibers prepared in each embodiment. The specific process is as follows: the polyester fiber is first placed in an environment with a temperature of 20°C and a humidity of 65% for 4 hours, and then clamped by upper and lower clamps (clamping length of 500 mm), and a pre-tension of 0.05 cN / dtex is applied by a manipulator to stabilize the polyester fiber. At the beginning of the test, the lower clamp stretches the tow at a uniform speed of 500 mm / min until the tow breaks. At the same time, the real-time data of the force sensor during the stretching process is recorded, and the relationship curve between strength and elongation is drawn through the data collection system. Finally, the breaking strength and elongation of the tow are obtained through data processing and analysis.
[0044] Boiling Water Shrinkage: Based on the boiling water shrinkage of the skein method in the "Test Method for Thermal Shrinkage of Chemical Fiber Filaments (After Treatment)" (GB / T 6505-2017), under specified test conditions, the sample is treated with boiling water. The change in sample length before and after treatment is measured and calculated as a percentage of the original filament length to obtain the boiling water shrinkage.
[0045] Dyeing evenness: According to GB / T 6508-2015 "Test method for dyeing evenness of polyester filament yarn," the high-shrinkage polyester fibers prepared in each example were woven into 10 cm socks and then dyed. The dyeing evenness of the socks was then visually assessed using a gray scale to compare the discoloration.
[0046] Example 1
[0047] A method for producing high-shrinkage polyester fiber, comprising the following steps:
[0048] (1) High shrinkage polyester chips with an intrinsic viscosity of 0.68 dL / g and a melting point of 235°C were dried at a drying temperature of 160°C, a drying time of 12 hours, and a dew point of -99°C. After drying, the moisture content of the high shrinkage polyester chips was 42 ppm.
[0049] The screw injection device is divided into five zones, with the temperature of screw zone 1 being 258°C, the temperature of screw zone 2 being 268°C, the temperature of screw zone 3 being 270°C, the temperature of screw zone 4 being 270°C, and the temperature of screw zone 5 being 272°C. The extrusion pressure of the screw injection device is 13.0 MPa.
[0050] (2) The dried high shrinkage polyester chips were added to a conventional polyester melt having an intrinsic viscosity of 0.622 dL / g through a screw injection device to obtain a mixed melt;
[0051] The addition amount of high shrinkage polyester chips is 14 wt% of the mixed melt;
[0052] (3) The mixed melt enters the spinning manifold after melt conveying and melt distribution, and after melt spinning, it is sequentially cooled, lubricated for the first time, pre-internetted for the first time, GR1 godet roller, HR2 hot roller, HR3 hot roller, HR4 hot roller, HR5 hot roller, GR6 godet roller, lubricated for the second time, pre-internetted for the second time, main internet, GR7 godet roller and winding to obtain high shrinkage polyester fiber;
[0053] like Figure 1 As shown, a metering pump base is provided on the upper surface of the spinning manifold 1, and the metering pump is installed above the metering pump base. 24 melt diversion tubes 2 are provided in the spinning manifold 1, and one melt diversion tube 2 includes a melt diversion tube I, a melt diversion tube II, and four melt heat exchange tubes; the upper end of the melt diversion tube I is connected to the metering pump base through a melt diversion plate, the upper ends of the four melt heat exchange tubes are simultaneously connected to the lower end of the melt diversion tube I, and the lower ends of the four melt heat exchange tubes are simultaneously connected to the upper end of the melt diversion tube II, the lower end of the melt diversion tube II is connected to the input end of the static mixer 4, and the output end of the static mixer 4 is connected to the spinning assembly;
[0054] The four melt heat exchange tubes are simultaneously wrapped by a heat exchange jacket 3, which is used to heat the temperature of the melt in the melt diversion tube to 290°C. The spinning manifold 1 is provided with a heat medium tube 5 and a heat medium return tube 6. All heat exchange jackets 3 are simultaneously connected to the heat medium tube 5 and the heat medium return tube 6. The input ends of all heat exchange jackets 3 are connected to the output ends of the heat medium tube 5, and the output ends of all heat exchange jackets 3 are connected to the input ends of the heat medium return tube 6. The input ends of the heat medium tube 5 and the output ends of the heat medium return tube 6 are both connected to the heat medium station. The temperature of the heat medium introduced into the heat medium tube 5 is 305°C.
[0055] The process parameters include: the temperature of the spinning manifold 1 is 285°C; the temperature of the HR2 hot roller is 50°C; the temperature of the HR3 hot roller is 55°C; the distance between the HR2 hot roller and the HR3 hot roller is 4.8 cm; the temperature of the HR4 hot roller is 45°C; the temperature of the HR5 hot roller is 45°C; the distance between the HR3 hot roller and the HR4 hot roller is 4.8 cm; the roughness of the GR1, HR2, HR3 and HR4 hot rollers is 0.08 μm, and the roughness of the HR5, GR6 and GR7 hot rollers is 1.3 μm; the contact length of the filament bundle with the GR1 godet is 25% of the circumference of the GR1 godet, and the contact length of the filament bundle with the HR2, HR3 and HR4 hot rollers is 0.08 μm. The circumference of the HR2, HR3 and HR4 hot rollers is 60% of the circumference of the HR5 hot roller. The contact length of the tow with the HR5 hot roller is 60% of the circumference of the HR5 hot roller. The contact length of the tow with the GR6 and GR7 godet rollers is 48% of the circumference of the GR6 and GR7 godet rollers respectively. The speed of the GR1 godet roller is 1630 m / min; the speed of the HR2 hot roller is 1630 m / min; the speed of the HR3 hot roller is 1730 m / min; the speed of the HR4 hot roller is 3980 m / min; the speed of the HR5 hot roller is 3980 m / min; the speed of the GR6 godet roller is 4000 m / min; the speed of the GR7 godet roller is 4000 m / min; and the winding speed is 4000 m / min.
[0056] When the replacement cycle of the spinneret assembly is 45 days, the pressure of the spinneret assembly rises by 1.9 MPa, the number of floating fibers accounts for 0.03%, and the breakage rate is 3.6%.
[0057] The high shrinkage polyester fiber finally obtained has a breaking strength of 3.96 cN / dtex, an elongation at break of 29.3%, a boiling water shrinkage of 33.9%, and a dyeing uniformity of level 4-5.
[0058] Example 2
[0059] A method for producing high-shrinkage polyester fiber, comprising the following steps:
[0060] (1) High shrinkage polyester chips with an intrinsic viscosity of 0.7 dL / g and a melting point of 240°C were dried at a drying temperature of 162°C, a drying time of 11 hours, and a dew point of -100°C. After drying, the moisture content of the high shrinkage polyester chips was 45 ppm.
[0061] The screw injection device is divided into five zones, with the temperature of screw zone 1 being 259°C, the temperature of screw zone 2 being 269°C, the temperature of screw zone 3 being 271°C, the temperature of screw zone 4 being 271°C, and the temperature of screw zone 5 being 273°C. The extrusion pressure of the screw injection device is 13.6MPa.
[0062] (2) The dried high shrinkage polyester chips were added to a conventional polyester melt having an intrinsic viscosity of 0.62 dL / g through a screw injection device to obtain a mixed melt;
[0063] The addition amount of high shrinkage polyester chips is 14.5wt% of the mixed melt;
[0064] (3) The mixed melt enters the spinning manifold after melt conveying and melt distribution, and after melt spinning, it is sequentially cooled, lubricated for the first time, pre-internetted for the first time, GR1 godet roller, HR2 hot roller, HR3 hot roller, HR4 hot roller, HR5 hot roller, GR6 godet roller, lubricated for the second time, pre-internetted for the second time, main internet, GR7 godet roller and winding to obtain high shrinkage polyester fiber;
[0065] A metering pump base is provided on the upper surface of the spinning manifold, and the metering pump is installed above the metering pump base. The spinning manifold is provided with 20 melt diversion tubes, and one melt diversion tube includes a melt diversion tube I, a melt diversion tube II, and five melt heat exchange tubes; the upper end of the melt diversion tube I is connected to the metering pump base through a melt diversion plate, the upper ends of the five melt heat exchange tubes are simultaneously connected to the lower end of the melt diversion tube I, and the lower ends of the five melt heat exchange tubes are simultaneously connected to the upper end of the melt diversion tube II. The lower end of the melt diversion tube II is connected to the input end of a static mixer, and the output end of the static mixer is connected to the spinning assembly;
[0066] Five melt heat exchange tubes are simultaneously wrapped in a heat exchange jacket, which is used to heat the temperature of the melt in the melt diversion tube to 291°C. The spinning manifold is equipped with a heat medium tube and a heat medium return tube. All heat exchange jackets are connected to the heat medium tube and the heat medium return tube at the same time. The input ends of all heat exchange jackets are connected to the output ends of the heat medium tube, and the output ends of all heat exchange jackets are connected to the input ends of the heat medium return tube. The input ends of the heat medium tube and the output ends of the heat medium return tube are both connected to the heat medium station. The temperature of the heat medium entering the heat medium tube is 310°C.
[0067] The process parameters include: the temperature of the spinning manifold is 286°C; the temperature of the HR2 hot roller is 51°C; the temperature of the HR3 hot roller is 56°C; the distance between the HR2 hot roller and the HR3 hot roller is 4.9 cm; the temperature of the HR4 hot roller is 46°C; the temperature of the HR5 hot roller is 46°C; the distance between the HR3 hot roller and the HR4 hot roller is 4.9 cm; the roughness of the GR1, HR2, HR3 and HR4 hot rollers is 0.09 μm, and the roughness of the HR5, GR6 and GR7 godet rollers is 1.4 μm; the contact length of the tow with the GR1 godet roller is 28% of the circumference of the GR1 godet roller, and the contact length of the tow with the HR2, HR3 and HR4 hot rollers is H The contact length between the filament bundle and the HR5 hot roller is 61% of the circumference of the HR5 hot roller, and the contact length between the filament bundle and the GR6 and GR7 godet rollers is 49% of the circumference of the GR6 and GR7 godet rollers respectively. The speed of the GR1 godet roller is 1640 m / min; the speed of the HR2 hot roller is 1650 m / min; the speed of the HR3 hot roller is 1740 m / min; the speed of the HR4 hot roller is 4000 m / min; the speed of the HR5 hot roller is 4000 m / min; the speed of the GR6 godet roller is 4020 m / min; the speed of the GR7 godet roller is 4020 m / min; and the winding speed is 4020 m / min.
[0068] When the replacement cycle of the spinneret assembly is 45 days, the pressure of the spinneret assembly rises by 1.8 MPa, the number of floating fibers accounts for 0.02%, and the breakage rate is 4.5%.
[0069] The high shrinkage polyester fiber finally obtained has a breaking strength of 3.94 cN / dtex, an elongation at break of 31%, a boiling water shrinkage of 33.2%, and a dyeing uniformity of level 4-5.
[0070] Example 3
[0071] A method for producing high-shrinkage polyester fiber, comprising the following steps:
[0072] (1) High shrinkage polyester chips with an intrinsic viscosity of 0.74 dL / g and a melting point of 242°C were dried at a drying temperature of 165°C, a drying time of 10 hours, and a dew point of -101°C. After drying, the moisture content of the high shrinkage polyester chips was 48 ppm.
[0073] The screw injection device is divided into five zones, with the temperature of screw zone 1 being 260°C, the temperature of screw zone 2 being 270°C, the temperature of screw zone 3 being 272°C, the temperature of screw zone 4 being 272°C, and the temperature of screw zone 5 being 275°C. The extrusion pressure of the screw injection device is 13.2MPa.
[0074] (2) The dried high shrinkage polyester chips were added to a conventional polyester melt having an intrinsic viscosity of 0.63 dL / g through a screw injection device to obtain a mixed melt;
[0075] The addition amount of high shrinkage polyester chips is 15wt% of the mixed melt;
[0076] (3) The mixed melt enters the spinning manifold after melt conveying and melt distribution, and after melt spinning, it is sequentially cooled, lubricated for the first time, pre-internetted for the first time, GR1 godet roller, HR2 hot roller, HR3 hot roller, HR4 hot roller, HR5 hot roller, GR6 godet roller, lubricated for the second time, pre-internetted for the second time, main internet, GR7 godet roller and winding to obtain high shrinkage polyester fiber;
[0077] A metering pump base is provided on the upper surface of the spinning manifold, and the metering pump is installed above the metering pump base. The spinning manifold is provided with 32 melt diversion tubes, and one melt diversion tube includes a melt diversion tube I, a melt diversion tube II, and 6 melt heat exchange tubes; the upper end of the melt diversion tube I is connected to the metering pump base through a melt diversion plate, the upper ends of the 6 melt heat exchange tubes are simultaneously connected to the lower end of the melt diversion tube I, and the lower ends of the 6 melt heat exchange tubes are simultaneously connected to the upper end of the melt diversion tube II. The lower end of the melt diversion tube II is connected to the input end of a static mixer, and the output end of the static mixer is connected to the spinning assembly;
[0078] Six melt heat exchange tubes are simultaneously wrapped in a heat exchange jacket, which is used to heat the temperature of the melt in the melt diversion tube to 292°C. The spinning manifold is equipped with a heat medium tube and a heat medium return tube. All heat exchange jackets are connected to the heat medium tube and the heat medium return tube. The input ends of all heat exchange jackets are connected to the output ends of the heat medium tubes, and the output ends of all heat exchange jackets are connected to the input ends of the heat medium return tubes. The input ends of the heat medium tubes and the output ends of the heat medium return tubes are both connected to the heat medium station. The temperature of the heat medium entering the heat medium tubes is 315°C.
[0079] The process parameters include: the temperature of the spinning manifold is 287℃; the temperature of the HR2 hot roller is 52℃; the temperature of the HR3 hot roller is 57℃; the distance between the HR2 hot roller and the HR3 hot roller is 5cm; the temperature of the HR4 hot roller is 47℃; the temperature of the HR5 hot roller is 47℃; the distance between the HR3 hot roller and the HR4 hot roller is 5cm; the roughness of the GR1, HR2, HR3 and HR4 hot rollers is 0.1μm, and the roughness of the HR5, GR6 and GR7 godet rollers is 1.5μm; the contact length of the filament bundle with the GR1 godet roller is 26% of the circumference of the GR1 godet roller, and the contact lengths of the filament bundle with the HR2, HR3 and HR4 hot rollers are 0.1μm, 0.1μm and 0.1μm, respectively. The contact lengths of the 3rd and HR4 hot rollers are 62%, 62% and 62.5% of the circumferences of the HR3 and HR4 hot rollers, respectively; the contact lengths of the tow with the HR5 hot roller are 63% of the circumference of the HR5 hot roller; the contact lengths of the tow with the GR6 and GR7 godet rollers are both 50% of the circumferences of the GR6 and GR7 godet rollers; the speed of the GR1 godet roller is 1650m / min; the speed of the HR2 hot roller is 1655m / min; the speed of the HR3 hot roller is 1770m / min; the speed of the HR4 hot roller is 4020m / min; the speed of the HR5 hot roller is 4020m / min; the speed of the GR6 godet roller is 4040m / min; the speed of the GR7 godet roller is 4040m / min; and the winding speed is 4040m / min.
[0080] When the replacement cycle of the spinneret assembly is 45 days, the pressure of the spinneret assembly rises by 1.6 MPa, the number of floating fibers accounts for 0.03%, and the breakage rate is 5.1%.
[0081] The high shrinkage polyester fiber finally obtained has a breaking strength of 3.89 cN / dtex, an elongation at break of 30.5%, a boiling water shrinkage of 34.7%, and a dyeing uniformity of level 4-5.
[0082] Example 4
[0083] A method for producing high-shrinkage polyester fiber, comprising the following steps:
[0084] (1) High shrinkage polyester chips with an intrinsic viscosity of 0.75 dL / g and a melting point of 245°C were dried at a drying temperature of 161°C, a drying time of 11.5 hours, and a dew point of -99.5°C. After drying, the moisture content of the high shrinkage polyester chips was 43 ppm.
[0085] The screw injection device is divided into five zones, with the temperature of screw zone 1 being 258.5°C, the temperature of screw zone 2 being 269°C, the temperature of screw zone 3 being 270.5°C, the temperature of screw zone 4 being 270.5°C, and the temperature of screw zone 5 being 273°C. The extrusion pressure of the screw injection device is 14.0 MPa.
[0086] (2) The dried high shrinkage polyester chips were added to a conventional polyester melt having an intrinsic viscosity of 0.625 dL / g through a screw injection device to obtain a mixed melt;
[0087] The addition amount of high shrinkage polyester chips is 15.6wt% of the mixed melt;
[0088] (3) The mixed melt enters the spinning manifold after melt conveying and melt distribution, and after melt spinning, it is sequentially cooled, lubricated for the first time, pre-internetted for the first time, GR1 godet roller, HR2 hot roller, HR3 hot roller, HR4 hot roller, HR5 hot roller, GR6 godet roller, lubricated for the second time, pre-internetted for the second time, main internet, GR7 godet roller and winding to obtain high shrinkage polyester fiber;
[0089] A metering pump base is provided on the upper surface of the spinning manifold, and the metering pump is installed above the metering pump base. The spinning manifold is provided with 24 melt diversion tubes, and one melt diversion tube includes a melt diversion tube I, a melt diversion tube II, and four melt heat exchange tubes; the upper end of the melt diversion tube I is connected to the metering pump base through a melt diversion plate, the upper ends of the four melt heat exchange tubes are simultaneously connected to the lower end of the melt diversion tube I, and the lower ends of the four melt heat exchange tubes are simultaneously connected to the upper end of the melt diversion tube II. The lower end of the melt diversion tube II is connected to the input end of a static mixer, and the output end of the static mixer is connected to the spinning assembly;
[0090] The four melt heat exchange tubes are simultaneously wrapped in a heat exchange jacket, which is used to heat the temperature of the melt in the melt diversion tube to 290.5°C. The spinning manifold is provided with a heat medium tube and a heat medium return tube. All heat exchange jackets are simultaneously connected to the heat medium tube and the heat medium return tube. The input ends of all heat exchange jackets are connected to the output ends of the heat medium tubes, and the output ends of all heat exchange jackets are connected to the input ends of the heat medium return tubes. The input ends of the heat medium tubes and the output ends of the heat medium return tubes are both connected to the heat medium station. The temperature of the heat medium entering the heat medium tubes is 308°C.
[0091] The process parameters include: the temperature of the spinning beam is 288°C; the temperature of the HR2 hot roller is 53°C; the temperature of the HR3 hot roller is 58°C; the distance between the HR2 hot roller and the HR3 hot roller is 5.1 cm; the temperature of the HR4 hot roller is 48°C; the temperature of the HR5 hot roller is 49°C; the distance between the HR3 hot roller and the HR4 hot roller is 5.1 cm; the roughness of the GR1, HR2, HR3 and HR4 hot rollers is 0.11 μm, and the roughness of the HR5, GR6 and GR7 hot rollers is 1.6 μm; the contact length of the filament bundle with the GR1 godet is 27% of the circumference of the GR1 godet, and the contact length of the filament bundle with the HR2, HR3 and HR4 hot rollers is 1.6 μm. The circumferences of the HR3 and HR4 hot rollers are 63%, 64% and 63.5% respectively; the contact length of the tow with the HR5 hot roller is 65% of the circumference of the HR5 hot roller; the contact length of the tow with the GR6 and GR7 godet rollers is 48% of the circumference of the GR6 and GR7 godet rollers respectively; the speed of the GR1 godet roller is 1660m / min; the speed of the HR2 hot roller is 1665m / min; the speed of the HR3 hot roller is 1730m / min; the speed of the HR4 hot roller is 3990m / min; the speed of the HR5 hot roller is 3990m / min; the speed of the GR6 godet roller is 4010m / min; the speed of the GR7 godet roller is 4010m / min; and the winding speed is 4010m / min.
[0092] When the replacement cycle of the spinneret assembly is 45 days, the pressure of the spinneret assembly rises by 1.8 MPa, the number of floating fibers accounts for 0.02%, and the breakage rate is 6.2%.
[0093] The high shrinkage polyester fiber finally obtained has a breaking strength of 4.01 cN / dtex, an elongation at break of 31.4%, a boiling water shrinkage of 34.3%, and a dyeing uniformity of level 4-5.
[0094] Example 5
[0095] A method for producing high-shrinkage polyester fiber, comprising the following steps:
[0096] (1) High shrinkage polyester chips with an intrinsic viscosity of 0.78 dL / g and a melting point of 243°C were dried at a drying temperature of 164°C, a drying time of 10.5 hours, and a dew point of -100.5°C. After drying, the moisture content of the high shrinkage polyester chips was 46 ppm.
[0097] The screw injection device is divided into five zones, with the temperature of screw zone 1 being 259.5°C, the temperature of screw zone 2 being 268°C, the temperature of screw zone 3 being 271.5°C, the temperature of screw zone 4 being 271.5°C, and the temperature of screw zone 5 being 273°C. The extrusion pressure of the screw injection device is 13.3MPa.
[0098] (2) The dried high shrinkage polyester chips were added to a conventional polyester melt having an intrinsic viscosity of 0.628 dL / g through a screw injection device to obtain a mixed melt;
[0099] The addition amount of high shrinkage polyester chips is 16 wt% of the mixed melt;
[0100] (3) The mixed melt enters the spinning manifold after melt conveying and melt distribution, and after melt spinning, it is sequentially cooled, lubricated for the first time, pre-internetted for the first time, GR1 godet roller, HR2 hot roller, HR3 hot roller, HR4 hot roller, HR5 hot roller, GR6 godet roller, lubricated for the second time, pre-internetted for the second time, main internet, GR7 godet roller and winding to obtain high shrinkage polyester fiber;
[0101] A metering pump base is provided on the upper surface of the spinning manifold, and the metering pump is installed above the metering pump base. The spinning manifold is provided with 32 melt diversion tubes, and one melt diversion tube includes a melt diversion tube I, a melt diversion tube II, and 6 melt heat exchange tubes; the upper end of the melt diversion tube I is connected to the metering pump base through a melt diversion plate, the upper ends of the 6 melt heat exchange tubes are simultaneously connected to the lower end of the melt diversion tube I, and the lower ends of the 6 melt heat exchange tubes are simultaneously connected to the upper end of the melt diversion tube II. The lower end of the melt diversion tube II is connected to the input end of a static mixer, and the output end of the static mixer is connected to the spinning assembly;
[0102] Six melt heat exchange tubes are simultaneously wrapped in a heat exchange jacket, which is used to heat the temperature of the melt in the melt diversion tube to 291.5°C. The spinning manifold is equipped with a heat medium tube and a heat medium return tube. All heat exchange jackets are simultaneously connected to the heat medium tube and the heat medium return tube. The input ends of all heat exchange jackets are connected to the output ends of the heat medium tubes, and the output ends of all heat exchange jackets are connected to the input ends of the heat medium return tubes. The input ends of the heat medium tubes and the output ends of the heat medium return tubes are both connected to the heat medium station. The temperature of the heat medium entering the heat medium tubes is 312°C.
[0103] The process parameters include: the temperature of the spinning manifold is 285℃; the temperature of the HR2 hot roller is 55℃; the temperature of the HR3 hot roller is 60℃; the distance between the HR2 hot roller and the HR3 hot roller is 5.2cm; the temperature of the HR4 hot roller is 50℃; the temperature of the HR5 hot roller is 50℃; the distance between the HR3 hot roller and the HR4 hot roller is 5.2cm; the roughness of the GR1, HR2, HR3 and HR4 hot rollers is 0.12μm, and the roughness of the HR5, GR6 and GR7 godet rollers is 1.7μm; the contact length of the tow with the GR1 godet roller is 26% of the circumference of the GR1 godet roller, and the contact length of the tow with the HR2, HR3 and HR4 hot rollers is H The contact length between the tow and the HR5 hot roller is 64% of the circumference of the HR5 hot roller, and the contact length between the tow and the GR6 and GR7 godet rollers is 49% of the circumference of the GR6 and GR7 godet rollers. The speed of the GR1 godet roller is 1670 m / min; the speed of the HR2 hot roller is 1670 m / min; the speed of the HR3 hot roller is 1750 m / min; the speed of the HR4 hot roller is 4010 m / min; the speed of the HR5 hot roller is 4010 m / min; the speed of the GR6 godet roller is 4030 m / min; the speed of the GR7 godet roller is 4030 m / min; and the winding speed is 4030 m / min.
[0104] When the replacement cycle of the spinneret assembly is 45 days, the pressure of the spinneret assembly rises by 1.5 MPa, the number of floating fibers accounts for 0.01%, and the breakage rate is 4.7%.
[0105] The high shrinkage polyester fiber finally obtained has a breaking strength of 4.03 cN / dtex, an elongation at break of 29.8%, a boiling water shrinkage of 34.9%, and a dyeing uniformity of level 4-5.
Claims
1. A method for producing high shrinkage polyester fiber, characterized in that: High-shrinkage polyester chips are added to conventional polyester melts through a screw injection device to obtain a mixed melt. The mixed melt enters a spinning manifold after melt conveying and melt distribution. After melt spinning, it is cooled, lubricated for the first time, pre-interlaced for the first time, GR1 godet roller, HR2 hot roller, HR3 hot roller, HR4 hot roller, HR5 hot roller, GR6 godet roller, lubricated for the second time, pre-interlaced for the second time, main interlaced, GR7 godet roller, and wound to produce high-shrinkage polyester fibers. The intrinsic viscosity of the high shrinkage polyester chips is 0.68-0.78 dL / g, and the addition amount of the high shrinkage polyester chips is 14-16 wt% of the mixed melt; The intrinsic viscosity of conventional polyester melt is 0.620-0.630 dL / g; A metering pump base is provided on the upper surface of the spinning manifold, and the metering pump is installed above the metering pump base. A plurality of melt diversion pipes are provided in the spinning manifold, and the plurality of melt diversion pipes are connected to the metering pump base. Each melt diversion pipe is wrapped by a heat exchange jacket, and each melt diversion pipe is connected to the input end of a static mixer, and the output end of the static mixer is connected to the spinning assembly. The heat exchange jacket is used to heat the temperature of the melt in the melt diversion pipe to 290-292°C; When the replacement cycle of the spinneret assembly is 45 days, the pressure rise of the spinneret assembly is ≤2.0MPa, the proportion of floating fibers is ≤0.03%, and the breakage rate is ≤7%.
2. The method for producing high shrinkage polyester fiber according to claim 1, characterized in that: The melting point of high shrinkage polyester chips is 235-245°C.
3. The method for producing high shrinkage polyester fiber according to claim 1, characterized in that: The screw injection device is divided into five zones. The temperature of screw zone 1 is 258-260°C, the temperature of screw zone 2 is 268-270°C, the temperature of screw zone 3 is 270-272°C, the temperature of screw zone 4 is 270-272°C, and the temperature of screw zone 5 is 272-275°C.
4. The method for producing high shrinkage polyester fiber according to claim 1, wherein: The spinning box is equipped with a heat medium tube and a heat medium return tube. All heat exchange jackets are connected to the heat medium tube and the heat medium return tube at the same time. The input ends of all heat exchange jackets are connected to the output ends of the heat medium tube, and the output ends of all heat exchange jackets are connected to the input ends of the heat medium return tube. The input ends of the heat medium tube and the output ends of the heat medium return tube are both connected to the heat medium station; the temperature of the heat medium introduced into the heat medium tube is 305-315℃.
5. The method for producing high shrinkage polyester fiber according to claim 1, characterized in that: A melt diversion pipe includes a melt diversion pipe I, a melt diversion pipe II and 4 to 6 melt heat exchange pipes; the upper end of the melt diversion pipe I is connected to the metering pump base through a melt diversion plate, the upper ends of the 4 to 6 melt heat exchange pipes are simultaneously connected to the lower end of the melt diversion pipe I, the lower ends of the 4 to 6 melt heat exchange pipes are simultaneously connected to the upper end of the melt diversion pipe II, and the lower end of the melt diversion pipe II is connected to the input end of the static mixer; each heat exchange jacket simultaneously wraps 4 to 6 melt heat exchange pipes.
6. The method for producing high shrinkage polyester fiber according to claim 1, characterized in that: The high shrinkage polyester chips are first dried and then added into a screw injection device to be mixed with a conventional polyester melt. The drying temperature is 160-165°C, the drying time is 10-12 hours, the dew point is -99--101°C, and the moisture content of the high shrinkage polyester chips after drying is ≤50ppm.
7. The method for producing high shrinkage polyester fiber according to claim 1, characterized in that: The process parameters include: the temperature of the spinning manifold is 285-288°C; the temperature of the HR2 hot roller is 50-55°C; the temperature of the HR3 hot roller is 55-60°C; The distance between the HR2 and HR3 hot rollers is 4.8 to 5.2 cm; the temperature of the HR4 hot roller is 45 to 50 ° C; the temperature of the HR5 hot roller is 45 to 50 ° C; the distance between the HR3 and HR4 hot rollers is 4.8 to 5.2 cm; the HR2, HR3 and HR4 hot rollers are all smooth rollers with roughness of 0.1 ± 0.02 μm, 0.1 ± 0.02 μm and 0.1 ± 0.02 μm respectively; the contact lengths of the filaments with the HR2, HR3 and HR4 hot rollers are 100% and 100% respectively. and 60-65% of the circumference of the HR4 hot roller; the speed of the GR1 wire roller is 1650±20m / min; the speed of the HR2 hot roller is 1650±20m / min, the speed of the HR3 hot roller is 1750±20m / min; the speed of the HR4 hot roller is 4000±20m / min; the speed of the HR5 hot roller is 4000±20m / min; the speed of the GR6 wire roller is 4020±20m / min; the speed of the GR7 wire roller is 4020±20m / min; the winding speed is 4020±20m / min.
8. The high shrinkage polyester fiber produced by the production method according to any one of claims 1 to 7, characterized in that: The breaking strength of high shrinkage polyester fiber is ≥3.8cN / dtex, the breaking elongation is 30±2%, the boiling water shrinkage is 30-35%, and the dyeing uniformity is ≥level 4.