A method for preparing bio-based PA56 antibacterial functional masterbatch and ultrafine fiber

Abstract

The invention discloses a method for preparing a bio-based PA56 antibacterial functional masterbatch and ultrafine fiber, comprising the following steps: 1) dissolving a bio-based PA56 slice in hexafluoroisopropanol; 2) dissolving silver acetate in ammonia water to obtain a silver acetate ammonia complex; 3) adding the product prepared in 2) to the solution in 1) and stirring evenly; 4) diluting formic acid with hexafluoroisopropanol, and then dropping it into the mixed solution prepared in 3), stirring rapidly while dropping, continuing to stir after the dropping is completed, and then aging; 5) drying the product prepared in 4) by a rotary vacuum dryer, and then crushing; 6) preparing the product prepared in 5) into a bio-based PA56 antibacterial functional masterbatch with a nano-silver mass content of 2 to 3%. The functional masterbatch and the bio-based PA56 slice are melt-blended and spun to obtain a bio-based PA56 antibacterial ultrafine fiber. Excellent antibacterial properties can be obtained under the condition of a low nano-silver content.

Description

Technical Field

[0001] The invention relates to a preparation method of a bio-based PA56 antibacterial functional masterbatch and ultrafine fibers, and belongs to the technical field of functional fiber materials and fiber processing. Background Art

[0002] Chemical fibers can be divided into two categories: petroleum-based and bio-based, according to the source of raw materials. Petroleum-based chemical fibers account for more than 90%, and the resulting problems of oil resource shortage and environmental pollution are becoming increasingly severe. In September 2020, China proposed its carbon peak and carbon neutrality goals. Under the guidance of this national strategic goal, the green and low-carbon economic development model based on renewable resources, low energy consumption, low emissions and low pollution is the inevitable direction of fiber manufacturing in the future. Polyamide (PA) fiber, commonly known as nylon and nylon, is the second largest chemical fiber in the textile industry after polyester. Nylon is better than polyester and polypropylene in wear resistance, strength and elongation, flexibility, resilience, moisture absorption and breathability, and cold resistance. It is the preferred fabric for outdoor sports, leisure tourism, cold protection and warmth. With the implementation of the Healthy China strategy and the holding of some major events, sports and fitness have become a fashion. As the main consumption scene of nylon silk, outdoor sports, especially the ice and snow sports market, have also flourished. However, my country's nylon industry has always been at a disadvantage in international competition, mainly because the production and supply of hexamethylenediamine (adiponitrile), the raw material of polyhexamethylene adipamide (PA66), is monopolized by a few multinational companies such as INVISTA in the United States. In response to this dilemma and in line with the country's major strategic needs, Shanghai Cathay Biotechnology Co., Ltd. and other units have successfully adopted a biological method to produce pentamethylenediamine to replace petroleum-based hexamethylenediamine for the synthesis of polyamide materials (polypentamethylene adipamide, PA56). The successful development of bio-based pentamethylenediamine and PA56 has broken the long-term market monopoly of foreign companies on diamine raw materials for polyamide, ensuring the security of the industrial chain and supply chain, and effectively reducing the carbon emissions of chemical fiber production and dependence on petroleum resources.

[0003] During the wearing and use of clothing, it is inevitable to come into contact with various microorganisms such as bacteria and fungi. Fibers and products with antibacterial functions can kill a variety of bacteria, maintain hygiene, and protect health. Therefore, the development of fibers and products with antibacterial and deodorizing functions has high application value. Nanosilver-based antibacterial fibers have the advantages of safety, strong effect, broad spectrum, and durability, but nanosilver particles have large specific surface area and surface energy, and are very easy to agglomerate in the fiber-forming polymer matrix, affecting the antibacterial properties and fiber spinnability. At present, the method of loading nanosilver with micro-nano zirconium phosphate, titanium dioxide, and zeolite is generally used to solve the problem of nanosilver agglomeration. However, the particle size of the carrier material is large, and the nanosilver content is low (<5%). It is often necessary to add more silver-loaded antibacterial agents to the fiber, and it is difficult to spin ultrafine fibers (single filament fineness <0.66 dtex, diameter <8μm). 。 Summary of the invention

[0004] In view of the shortcomings of the prior art, the object of the present invention is to provide a method for preparing a bio-based PA56 antibacterial functional masterbatch and ultrafine fibers.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A method for preparing a bio-based PA56 antibacterial functional masterbatch, comprising the following steps:

[0007] 1) Dissolve bio-based PA56 slices in hexafluoroisopropanol;

[0008] 2) dissolving silver acetate in ammonia water to obtain silver acetate ammonia complex;

[0009] 3) adding the silver acetate ammine complex prepared in step 2) to the solution prepared in step 1) and stirring evenly;

[0010] 4) diluting formic acid with hexafluoroisopropanol, and then dropping it into the mixed solution prepared in step 3), stirring rapidly while dropping, and continuing to stir after the dropping is complete, and then aging;

[0011] 5) drying the product prepared in step 4) using a rotary vacuum dryer and then pulverizing;

[0012] 6) The product crushed in step 5) is extruded and granulated by a screw extruder to obtain a bio-based PA56 antibacterial functional masterbatch.

[0013] Preferably, in terms of mass ratio, the amount of silver acetate used is 3.2-4.8% of the bio-based PA56 slices.

[0014] Preferably, the NH 3 The molar ratio to silver acetate is 2.5 to 3.0:1.

[0015] Preferably, the molar ratio of formic acid to silver acetate ammine complex is 2.0-2.5:1.

[0016] Preferably, the drying temperature in step 5) is 60-120°C and the vacuum degree is 0.

[0017] Preferably, the nanosilver mass content of the bio-based PA56 antibacterial functional masterbatch prepared in step 6) is 2-3%.

[0018] A method for preparing bio-based PA56 antibacterial ultrafine fibers comprises the steps of melt-blending and spinning bio-based PA56 slices and prepared bio-based PA56 antibacterial functional masterbatches to prepare ultrafine fibers with antibacterial functions.

[0019] Preferably, the blending mass ratio of the bio-based PA56 chips and the bio-based PA56 antibacterial functional masterbatch is 85 / 15 to 80 / 20.

[0020] Preferably, the single filament fineness of the ultrafine fiber is 0.40-0.58 dtex, and the mass content of nano silver is 0.3-0.6%.

[0021] Beneficial effects of the present invention: Compared with the prior art, the nanosilver of the present application has no agglomeration in the PA56 matrix, is evenly dispersed and stable, does not require a carrier material, has good spinnability, and can be spun into ultrafine fibers with a single filament fineness of <0.66 dtex and a diameter of <8 μm. Excellent antibacterial properties can be obtained under conditions of a lower nanosilver content. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Existing nanosilver materials are very easy to agglomerate in the fiber-forming polymer matrix, affecting the antibacterial properties and fiber spinnability. In addition, the carrier nanosilver particles are large and the nanosilver content is low (<5%), so it is often necessary to add more silver-loaded antibacterial agents to the fibers, making it difficult to spin ultrafine fibers (single filament fineness <0.66 dtex, diameter <8μm).

[0024] The present invention discloses a method for preparing a bio-based PA56 antibacterial functional masterbatch, comprising the following steps:

[0025] 1) Dissolve the bio-based PA56 slices in hexafluoroisopropanol (CF 3 ) 2 CHOH;

[0026] 2) Silver acetate CH 3 COOAg is dissolved in ammonia to obtain silver acetate ammonia complex CH 3 COO(NH 3 ) 2 Ag;

[0027] 3) The silver acetate ammine complex prepared in step 2) is reacted with CH 3 COO(NH 3 ) 2 Add Ag to the solution prepared in step 1) and stir evenly;

[0028] 4) Formic acid HCOOH is reacted with hexafluoroisopropanol (CF 3 )2 After CHOH is diluted, it is added dropwise to the mixed solution prepared in step 3), and rapid stirring is performed while adding. After the addition is completed, stirring is continued, and then aging is performed;

[0029] 5) drying the product prepared in 4) in a rotary vacuum dryer, and then crushing it in a plastic crusher;

[0030] 6) The product prepared in step 5) is extruded and granulated through a screw extruder to obtain a bio-based PA56 antibacterial functional masterbatch.

[0031] In the technical solution adopted in this application, bio-based PA56 chips, CH 3 COO(NH 3 ) 2 Ag can be dissolved in (CF 3 ) 2 CHOH, forming a transparent homogeneous system. HCOOH as a reducing agent can convert CH 3 COO(NH 3 ) 2 Ag + Reduced to elemental silver. HCOOH and (CF 3 ) 2 CHOH is miscible and is also a good solvent for bio-based PA56 chips. 3 ) 2 After CHOH is diluted, it is added dropwise to the bio-based PA56 slices and CH 3 COO(NH 3 ) 2 Ag (CF 3 ) 2 In a CHOH homogeneous solution, the reaction can be milder and the aggregation of nanosilver can be avoided.

[0032] Preferably, by mass ratio, the silver acetate CH 3 The dosage of COOAg is 3.2-4.8% of bio-based PA56 chips. 3 If the amount of COOAg is too low, the antibacterial property of the final product will be poor. If the amount is too high, the product cost will increase and it will easily cause nanosilver agglomeration, affecting the spinnability.

[0033] Preferably, the NH 3 With silver acetate CH 3 The molar ratio of COOAg is 2.5-3.0:1. Theoretically, 1 mol of CH 3 COOAg and 2 mol NH 3 Reaction to form CH 3 COO(NH 3 ) 2 Ag. NH3 The purpose of excess is to make CH 3 All COOAg forms complexes, and the excess NH 3 Will evaporate during subsequent processing.

[0034] Preferably, the formic acid HCOOH and silver acetate ammine complex CH 3 COO(NH 3 ) 2 The molar ratio of Ag is 2.0 to 2.5:1. Theoretically, 1 mole of HCOOH can reduce 2 moles of CH 3 COO(NH 3 ) 2 Ag. The purpose of excess HCOOH is to make CH 3 COO(NH 3 ) 2 Ag + All of them are reduced to elemental Ag, and the excess HCOOH will evaporate during subsequent processing.

[0035] Preferably, the drying temperature in step 5) is 60-120°C and the vacuum degree is 0. At 60°C under normal pressure, (CF 3 ) 2 CHOH is evaporated and recovered, and then the temperature is gradually raised to 120°C for drying, such as 60°C-80°C-100°C-120°C, to completely remove excess HCOOH and NH 3 and CH 3 By-products such as COOH.

[0036] Preferably, the nanosilver mass content of the bio-based PA56 antibacterial functional masterbatch prepared in step 6) is 2-3%.

[0037] A method for preparing bio-based PA56 antibacterial ultrafine fibers comprises the steps of melt-blending and spinning bio-based PA56 slices and prepared bio-based PA56 antibacterial functional masterbatches to prepare ultrafine fibers with antibacterial functions.

[0038] Preferably, the blending mass ratio of the bio-based PA56 chips and the bio-based PA56 antibacterial functional masterbatch is 85 / 15 to 80 / 20.

[0039] Preferably, the single filament fineness of the ultrafine fiber is 0.40-0.58 dtex, and the mass content of nanosilver is 0.3-0.6%. If the nanosilver content is too high, the product cost will increase and the spinnability will be affected, and if the content is too low, the antibacterial property of the final product will be poor.

[0040] Example 1

[0041] A method for preparing a bio-based PA56 antibacterial functional masterbatch and ultrafine fibers comprises the following steps:

[0042] Step 1: Dissolve 1 kg of bio-based PA56 chips in 4 kg of hexafluoroisopropanol (CF 3 ) 2 CHOH;

[0043] Step 2: 0.032 kg (0.19 mol) of silver acetate CH 3 COOAg was dissolved in 0.033 kg of ammonia water (NH 3 The mass content is 25%, the actual NH 3 The content is 0.49 mol), and the silver acetate ammine complex CH 3 COO(NH 3 ) 2 Ag;

[0044] Step 3: The CH prepared in step 2 3 COO(NH 3 ) 2 Add Ag to the solution prepared in step 1 and stir evenly;

[0045] Step 4: 0.018 kg (0.39 mol) of formic acid HCOOH was mixed with 0.09 kg (CF 3 ) 2 After dilution, add CHOH dropwise (at a rate of 1-2 mL / min) to the mixed solution prepared in step 3, stirring rapidly (1000-1500 r / min) while adding. After the addition is complete, continue stirring for 30 min, and then age for 12 hours;

[0046] Step 5, drying the product prepared in step 4 in a rotary vacuum dryer at normal pressure (drying temperature and time: 60°C / 2h+80°C / 1h+100°C / 1h+120°C / 1h), and then crushing it in a plastic crusher;

[0047] Step 6: The product prepared in step 5 is melt-extruded and granulated by a screw extruder to obtain a bio-based PA56 antibacterial functional masterbatch. The extrusion process is a screw speed of 150 rpm, and the temperatures of each zone are 250±3°C, 255±3°C, 260±3°C, 265±3°C, 270±3°C, and 265±3°C. The nanosilver mass content of the functional masterbatch is 2.07%.

[0048] Step seven, 0.75 kg of the functional masterbatch prepared in step six and 4.25 kg of bio-based PA56 chips are melted, spun, stretched and wound to obtain ultrafine fibers with antibacterial function.

[0049] The spinning process is as follows: the screw speed is 45r / min, the temperatures of the screw extruder zones are 275±3℃, 288±3℃, 283±3℃, 283±3℃, 283±3℃, respectively, the spinneret diameter is 0.10 mm, the number of holes is 136, the annular air temperature is 18±1℃, the humidity is 95±2%, the wind speed is 0.40-0.45 m / s, and the winding speed is 4290m / min. The fiber specification is 55.6 dtex / 136f, the single filament fineness is 0.41 dtex, and the nano silver mass content is 0.31%.

[0050] Example 2

[0051] A method for preparing a bio-based PA56 antibacterial functional masterbatch and ultrafine fibers comprises the following steps:

[0052] Step 1: Dissolve 1 kg of bio-based PA56 chips in 4 kg of hexafluoroisopropanol (CF 3 ) 2 CHOH;

[0053] Step 2: 0.047 kg (0.28 mol) of silver acetate CH 3 COOAg was dissolved in 0.057 kg of ammonia water (NH 3 The mass content is 25%, the actual NH 3 The content is 0.84 mol), and the silver acetate ammine complex CH 3 COO(NH 3 ) 2 Ag;

[0054] Step 3: The CH prepared in step 2 3 COO(NH 3 ) 2 Add Ag to the solution prepared in step 1 and stir evenly;

[0055] Step 4: 0.032 kg (0.70 mol) of formic acid HCOOH was reacted with 0.16 kg (CF 3 ) 2 After dilution, add CHOH dropwise (at a rate of 1-2 mL / min) to the mixed solution prepared in step 3, stirring rapidly (1000-1500 r / min) while adding. After the addition is complete, continue stirring for 30 min, and then age for 12 hours;

[0056] Step 5, drying the product prepared in step 4 in a rotary vacuum dryer at normal pressure (drying temperature and time: 60°C / 2h+80°C / 1h+100°C / 1h+120°C / 1h), and then crushing it in a plastic crusher;

[0057] Step 6: The product prepared in step 5 is melt-extruded and granulated by a screw extruder to obtain a bio-based PA56 antibacterial functional masterbatch. The extrusion process is a screw speed of 150 rpm, and the temperatures of each zone are 250±3°C, 255±3°C, 260±3°C, 265±3°C, 270±3°C, and 265±3°C. The nanosilver mass content of the functional masterbatch is 2.91%.

[0058] Step 7: 1 kg of the functional masterbatch prepared in step 6 and 4 kg of bio-based PA56 slices are melted, spun, stretched and wound to obtain ultrafine fibers with antibacterial function. The spinning process is a screw speed of 45r / min, the temperatures of each zone of the screw extruder are 275±3℃, 288±3℃, 283±3℃, 283±3℃, 283±3℃, respectively, the spinneret diameter is 0.10 mm, the number of holes is 136, the annular air temperature is 18±1℃, the humidity is 95±2%, the wind speed is 0.40-0.45 m / s, and the winding speed is 4290m / min. The fiber specification is 77.8 dtex / 136f, the monofilament fineness is 0.57 dtex, and the nanosilver mass content is 0.58%.

[0059] The main performance indicators of the bio-based PA56 antibacterial ultrafine fibers described in Example 1 and Example 2 are shown in Table 1

[0060] Table 1 Main performance indicators of bio-based PA56 antibacterial microfiber

[0061]

[0062] The ultrafine fibers prepared by the technical solution of the present application can obtain excellent antibacterial properties under the condition of relatively low nanosilver content.

[0063] The embodiments should not be regarded as limiting the present invention, but any improvements made based on the spirit of the present invention should be within the protection scope of the present invention.

Claims

1. A method for preparing bio-based PA56 antibacterial ultrafine fibers, Features: The bio-based PA56 chips and the bio-based PA56 antibacterial functional masterbatch are melt-blended and spun to obtain ultrafine fibers with antibacterial function, wherein the blending mass ratio of the bio-based PA56 chips and the bio-based PA56 antibacterial functional masterbatch is 85 / 15 to 80 / 20. The preparation method of bio-based PA56 antibacterial functional masterbatch comprises the following steps: 1) Dissolve bio-based PA56 slices in hexafluoroisopropanol; 2) dissolving silver acetate in ammonia water to obtain silver acetate ammonia complex; 3) adding the silver acetate ammine complex prepared in step 2) to the solution prepared in step 1) and stirring evenly; 4) diluting formic acid with hexafluoroisopropanol, and then dropping it into the mixed solution prepared in step 3), stirring rapidly while dropping, and continuing to stir after the dropping is complete, and then aging; 5) drying the product prepared in step 4) using a rotary vacuum dryer and then pulverizing; 6) The product crushed in step 5) is extruded and granulated by a screw extruder to obtain a bio-based PA56 antibacterial functional masterbatch. The nanosilver mass content of the bio-based PA56 antibacterial functional masterbatch prepared in step 6) is 2-3%.

2. A method for preparing a bio-based PA56 antibacterial ultrafine fiber according to claim 1, Features: In terms of mass ratio, the amount of silver acetate used is 3.2-4.8% of the bio-based PA56 slices.

3. The method for preparing a bio-based PA56 antibacterial ultrafine fiber according to claim 1, Features: The available NH 3 The molar ratio to silver acetate is 2.5 to 3.0:

1.

4. The method for preparing a bio-based PA56 antibacterial ultrafine fiber according to claim 1, Features: The molar ratio of the formic acid to the silver acetate ammine complex is 2.0-2.5:

1.

5. The method for preparing the bio-based PA56 antibacterial ultrafine fiber according to claim 1, Features: The drying temperature in step 5) is 60-120°C and the vacuum degree is 0.

6. The method for preparing the bio-based PA56 antibacterial ultrafine fiber according to claim 1, Features: The single filament fineness of the ultrafine fiber is 0.40-0.58 dtex, and the mass content of nano silver is 0.3-0.6%.

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