Efficient preparation method of bio-based polymer melt-spun monofilament fiber

Abstract

The invention discloses an efficient preparation method of bio-based polymer melt-spun monofilament fibers. The method comprises the following steps: (1) performing porous spinning: performing porous spinning by using melt spinning equipment, regulating and controlling the number of holes, the diameter of each spinneret hole, the length of each spinneret hole and the pressure drop of a spinneret plate, and forming continuous, uniform and stable bio-based polymer multifilaments in the porous spinning process; and (2) mother yarn fiber splitting: regulating and controlling the technological parameters of mother yarn starting frequency, spindle starting frequency, tube bottom frequency, doffing plate acceleration segmentation, acceleration 1, acceleration 2, deceleration 1, deceleration 2, roller starting overfeeding, starting overfeeding and ending overfeeding by utilizing mother yarn fiber splitting equipment, and forming continuous, uniform and stable monofilaments of the bio-based polymer. By adopting the method disclosed by the invention, the production efficiency is remarkably improved, the fiber uniformity is improved, the fiber stability is improved, meanwhile, the product quality is remarkably improved, the market demand can be met, and the method has wide application value in the fields of clothing, decoration, industry and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of bio-based polymer and fiber material processing, and particularly relates to a method for efficiently preparing bio-based polymer melt-spun monofilament fibers. Background Art

[0002] Monofilament fibers are widely used in the three major application areas of textiles, namely, clothing, decoration, and industry. In particular, monofilaments with a fineness of ≤33dtex can be used in ultra-thin fabrics, clothing, accessories, ribbons, ties, wedding dresses, shoes, bags, scarves, curtain fabrics, filters, screens, surgical sutures, dental floss, ribbons, filter cloths, packaging bags, tea bags, wiping cloths, etc. Textile fabrics woven with monofilaments have superior properties, such as good drape, translucent hazy effect, light and soft, and good hand feel. Their clothing fabrics are deeply loved by users.

[0003] At present, monofilament fibers at home and abroad are mainly single filaments produced by single-hole spinnerets, such as polyester (PET) and nylon (PA) monofilaments. The production of melt-spun monofilament fibers has the characteristics of high technology, high efficiency, and high added value. At present, there are two main preparation technologies for monofilament fibers: 1) Spinning using the conventional unstretched yarn (UDY) process route, each spinneret spins a yarn, which is then stretched and wound to form a one-step spinning-drawing process for monofilaments. 2) The unstretched mother yarn is produced by conventional UDY equipment, and then stretched by a stretching machine to form a two-step preparation process for monofilaments in which the yarn is first spun and then drawn. When single-hole spinning technology is used to prepare monofilaments, the spinning speed is 700-900m / min, and the spinning speed and single-machine output are low; the storage period of UDY mother yarn is short, and the temperature and humidity requirements of the balance and storage environment are high; the quality of the monofilament is not high, the stability is poor, and uneven dyeing problems are prone to occur; the overall production efficiency is low, the operating cost is high, and the monofilament market is in short supply and cannot meet the current situation of market demand.

[0004] Based on this, the present invention proposes an efficient preparation method for bio-based polymer melt-spun monofilament fibers. The method successfully produces bio-based polymers with good mechanical properties, especially polylactic acid (PLA) and bio-based polyamide (PA11) melt-spun monofilament fibers through multi-hole spinning, equipment adjustment, process optimization, and mother fiber separation technology. Summary of the invention

[0005] The purpose of the present invention is to provide a method for efficiently preparing bio-based polymer melt-spun monofilament fibers in view of the deficiencies of the prior art. The method regulates the equipment, process and parameters of the multi-hole spinning and mother fiber division of melt spinning to form continuous, uniform and stable bio-based polymer melt-spun monofilaments. The technology of preparing bio-based polymer melt-spun monofilaments by multi-hole spinning-mother fiber division of the present invention can significantly improve production efficiency, improve fiber uniformity and mechanical properties, and at the same time improve fiber stability, significantly improve product quality, meet market demand, and be applied in the fields of clothing, decoration and industry.

[0006] The present invention is implemented by the following technical solutions:

[0007] A method for efficiently preparing bio-based polymer melt-spun monofilament fibers comprises the following steps:

[0008] (1) Multi-hole spinning: Multi-hole spinning is formed by melt spinning equipment to prepare multi-hole spinning fibers of bio-based polymers. The spinneret holes are arranged in concentric circles, with uniform liquid output. The number of holes, spinneret hole diameter, spinneret hole length, and pressure drop of the spinneret plate are regulated to form continuous, uniform, and stable multifilaments during the multi-hole spinning process.

[0009] (2) Mother yarn fiber separation: The multifilament is separated into multiple single yarns by using mother yarn fiber separation equipment. The process parameters of mother yarn starting frequency, spindle starting frequency, tube bottom frequency, yarn guide plate acceleration segmentation, acceleration 1, acceleration 2, deceleration 1, deceleration 2, roller start overfeeding, start overfeeding, and end overfeeding are adjusted respectively to form continuous, uniform, and stable single yarns.

[0010] In the above technical solution, further, the bio-based polymer is PLA or PA11;

[0011] Furthermore, in the step (1), the number of holes of the multi-hole spinneret is 6-12 holes, the diameter of the spinneret hole is 0.5-0.8 mm, the length of the spinneret hole is 1.5-3.0 mm, and the pressure drop of the spinneret plate is 10-16 MPa.

[0012] Furthermore, in the step (2), the multifilament is split into 2-12 single filaments.

[0013] Furthermore, the starting frequency of the mother yarn is 10-15Hz, the starting frequency of the spindle is 2.5-3.0Hz, the bottom frequency of the tube is 6.5-7.5Hz, the acceleration segment of the yarn delivery plate is 18-25%, the acceleration 1 is 3.5-4.0m / s, the acceleration 2 is 8.5-10.0m / s, the deceleration 1 is 3.5-4.0m / s, the deceleration 2 is 8.5-10.0m / s, the roller start overfeed is 140-160%, the starting overfeed is 120-150%, and the ending overfeed is 120-140%.

[0014] By adopting the above method, for the bio-based polymer PLA, 300D / 10F PLA multifilament is spun through multi-holes, and then the mother yarn is split to obtain multiple groups of 30D / 1F high-quality PLA monofilaments, with a fiber strength greater than 3.0cN / dtex and a boiling water shrinkage less than 35%. For the bio-based polymer PA11, 300D / 10F PA11 multifilament is spun through multi-holes, and then the mother yarn is split to obtain multiple groups of 30D / 1F high-quality PA11 monofilaments, with a fiber strength greater than 3.4cN / dtex and a boiling water shrinkage less than 34%.

[0015] The above technical solution has the following beneficial effects:

[0016] The present invention prepares bio-based polymer melt-spun multifilaments through multi-hole spinning technology, and the multifilaments of bio-based polymers are divided into single filaments after fiber division by regulating the mother fiber fiber division equipment and process technology, and a maximum of 12 single filaments can be formed. The number of holes, the diameter of the spinneret holes, the length of the spinneret holes, and the pressure drop of the spinneret plate are regulated to form continuous, uniform, and stable multifilaments during the multi-hole spinning process. The key process parameters of the mother fiber starting frequency, the spindle starting frequency, the tube bottom frequency, the yarn guide plate acceleration segmentation, the acceleration 1, the acceleration 2, the deceleration 1, the deceleration 2, the roller start overfeeding, the start overfeeding, and the end overfeeding are regulated respectively to form continuous, uniform, and stable single filaments. Compared with the existing single-hole spinning technology for preparing monofilaments on the market, the technology of preparing bio-based polymer melt-spun monofilaments by multi-hole spinning-mother fiber division of the present invention significantly improves production efficiency, improves fiber uniformity, improves fiber stability, and significantly improves product quality, can meet market demand, and is applied in the fields of clothing, decoration, and industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below in conjunction with the accompanying drawings:

[0018] Figure 1 Schematic diagram of the preparation process of PLA from multifilament to monofilament by multi-hole spinning in Example 1;

[0019] Figure 2 The PLA fiber (mother fiber) of the multi-hole spinning in Example 1

[0020] Figure 3 The PLA monofilament in Example 1;

[0021] Figure 4 It is the multiple stretching curve of the PLA mother yarn produced by multi-hole spinning in Example 1;

[0022] Figure 5 This is the multiple stretching curve of the PLA monofilament in Example 1.

[0023] Figure 6 It is the PA11 monofilament in Example 2. DETAILED DESCRIPTION

[0024] The technical solution of the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0025] Example 1

[0026] (1) A multi-hole spinneret (6 holes) was formed by melt spinning equipment, the spinneret hole diameter was 0.5 mm, the spinneret hole length was 1.5 mm, and the pressure drop of the spinneret plate was 10 MPa, to prepare a multi-hole spinneret fiber of a bio-based polymer. By adjusting the number of holes, the spinneret hole diameter, the spinneret hole length, and the pressure drop of the spinneret plate, a continuous, uniform, and stable multifilament was formed during the multi-hole spinning process. The obtained mother fiber is as follows Figure 2 As shown in Figure 2, the tensile properties of the multiple tests are as follows: Figure 4 .

[0027] (2) Using the mother fiber splitting equipment, 12 single fibers are formed, such as Figure 1 As shown. The starting frequency of the mother yarn is 10Hz, the starting frequency of the spindle is 2.5Hz, the bottom frequency of the tube is 6.5Hz, the acceleration segment of the yarn guide plate is 18%, the acceleration 1 is 3.5m / s, the acceleration 2 is 8.5m / s, the deceleration 1 is 3.5m / s, the deceleration 2 is 8.5m / s, the roller start overfeed is 140%, the starting overfeed is 120%, and the ending overfeed is 120%. By regulating the key process parameters of the mother yarn starting frequency, the spindle starting frequency, the bottom frequency of the tube, the acceleration segment of the yarn guide plate, the acceleration 1, the acceleration 2, the deceleration 1, the deceleration 2, the roller start overfeed, the starting overfeed, and the ending overfeed, a continuous, uniform and stable monofilament is formed.

[0028] (3) Under the optimized conditions of (1) and (2) above, 300D / 10F PLA multifilament was spun by multi-hole spinning, and then the mother yarn was split into fibers to obtain multiple groups of 30D / 1F high-quality PLA monofilaments, with a fiber strength greater than 3.0 cN / dtex and a boiling water shrinkage less than 35%. Figure 3 , Figure 5 The PLA monofilament prepared under the above optimized conditions has excellent uniformity and stability.

[0029] Example 2

[0030] (1) A multi-hole spinneret (6 holes) was formed by melt spinning equipment, the spinneret hole diameter was 0.8 mm, the spinneret hole length was 3.0 mm, and the pressure drop of the spinneret plate was 16 MPa to prepare a multi-hole spinneret fiber of a bio-based polymer. By adjusting the number of holes, the spinneret hole diameter, the spinneret hole length, and the pressure drop of the spinneret plate, a continuous, uniform, and stable multifilament was formed during the multi-hole spinning process.

[0031] (2) Use the mother fiber splitting equipment to form 12 single fibers. The mother fiber starting frequency is 15Hz, the spindle starting frequency is 3.0Hz, the tube bottom frequency is 7.5Hz, the yarn guide plate acceleration segment is 25%, the acceleration 1 is 4.0m / s, the acceleration 2 is 10.0m / s, the deceleration 1 is 4.0m / s, the deceleration 2 is 10.0m / s, the roller start overfeed is 160%, the starting overfeed is 150%, and the ending overfeed is 140%. By regulating the key process parameters of the mother fiber starting frequency, the spindle starting frequency, the tube bottom frequency, the yarn guide plate acceleration segment, acceleration 1, acceleration 2, deceleration 1, deceleration 2, the roller start overfeed, the starting overfeed, and the ending overfeed, continuous, uniform, and stable single fibers are formed.

[0032] (3) Under the optimized conditions of (1) and (2) above, 300D / 10F PA11 multifilament was spun by multi-hole spinning, and then the mother yarn was split into fibers to obtain multiple groups of 30D / 1F high-quality PA11 monofilaments, with a fiber strength greater than 3.4 cN / dtex and a boiling water shrinkage less than 34%. Figure 6 shown.

[0033] Table 1 shows the main performance parameters of bio-based polymer multifilaments and monofilaments of Examples 1 and 2. Compared with the conventional single-hole spinneret for preparing PLA monofilaments or PA11 monofilaments, there are problems such as low spinning speed, low production efficiency, incomplete drawing, low monofilament quality, poor stability, and uneven dyeing. The present invention uses the technology of preparing bio-based polymer melt-spun monofilaments through multi-hole spinneret-mother fiber fiber division, which significantly improves the production efficiency, especially by adjusting the corresponding parameters to improve the fiber uniformity, improve the fiber stability, and significantly improve the product quality. Not only the spinning speed is high and the production efficiency is high, the prepared PLA monofilaments or PA11 monofilaments are fully drawn, the monofilaments are of high quality, the uniformity and stability are good, and they are easy to dye.

[0034] Table 1. Main performance parameters of bio-based polymer multifilament and monofilament

[0035]

Claims

1. A method for efficiently preparing bio-based polymer melt-spun monofilament fibers, characterized in that: The steps include: 1) Melt spinning the bio-based polymer using a multi-hole spinneret, wherein the spinneret holes are arranged in concentric circles and the liquid output is uniform; the number of holes, the spinneret hole diameter, the spinneret hole length, and the pressure drop of the spinneret are regulated to form continuous, uniform, and stable multifilaments of the bio-based polymer during the multi-hole spinning process; 2) The bio-based polymer multifilament is processed by using the mother fiber fiber separation equipment and process to adjust the parameters of the mother fiber starting frequency, spindle starting frequency, tube bottom frequency, yarn guide plate acceleration segmentation, acceleration 1, acceleration 2, deceleration 1, deceleration 2, roller start overfeed, start overfeed, and end overfeed to form continuous, uniform, and stable bio-based polymer monofilament.

2. The method for efficiently preparing bio-based polymer melt-spun monofilament fibers according to claim 1, characterized in that: The bio-based polymer in step (1) is PLA or PA11.

3. The method for efficiently preparing bio-based polymer melt-spun monofilament fibers according to claim 1, characterized in that: In the step (1), the number of holes of the multi-hole spinneret is 6-12 holes, the diameter of the spinneret is 0.5-0.8 mm, the length of the spinneret is 1.5-3.0 mm, and the pressure drop of the spinneret is 10-16 MPa.

4. The method for efficiently preparing bio-based polymer melt-spun monofilament fibers according to claim 1, characterized in that: In the step (2), the mother fiber splitting equipment and process are used to realize the fiber splitting of the bio-based polymer multifilament into 2-12 single fibers.

5. The method for efficiently preparing bio-based polymer melt-spun monofilament fibers according to claim 1, characterized in that: In the step (2), the starting frequency of the mother yarn is 10-15 Hz, the starting frequency of the spindle is 2.5-3.0 Hz, the bottom frequency of the tube is 6.5-7.5 Hz, the acceleration segment of the yarn guide plate is 18-25%, the acceleration 1 is 3.5-4.0 m / s, the acceleration 2 is 8.5-10.0 m / s, the deceleration 1 is 3.5-4.0 m / s, the deceleration 2 is 8.5-10.0 m / s, the roller start overfeed is 140-160%, the initial overfeed is 120-150%, and the end overfeed is 120-140%.

6. The method for efficiently preparing bio-based polymer melt-spun monofilament fibers according to any one of claims 1 to 5, characterized in that: For the bio-based polymer PLA, 300D / 10F PLA multifilament is produced by multi-hole spinning, and then the mother yarn is divided into fibers to obtain multiple groups of 30D / 1F high-quality PLA monofilaments, with a fiber strength greater than 3.0cN / dtex and a boiling water shrinkage rate less than 35%.

7. The method for efficiently preparing bio-based polymer melt-spun monofilament fibers according to any one of claims 1 to 5, characterized in that: For the bio-based polymer PA11, 300D / 10F PA11 multifilament is produced by multi-hole spinning, and then the mother yarn is divided into fibers to obtain multiple groups of 30D / 1F high-quality PA11 monofilaments, with a fiber strength greater than 3.4cN / dtex and a boiling water shrinkage less than 34%.

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