Preparation method of traceable polyester staple fiber and product

Abstract

The invention discloses a preparation method of traceable polyester staple fibers, which comprises the following steps: mixing a tracing raw material and a renewable synthetic fiber raw material, and carrying out melt spinning to obtain the traceable regenerated polyester staple fibers, the tracing raw material comprising at least two of cobalt Prussian blue analogues, germanate fluorescent materials and metal oxides. The invention also provides a traceable polyester staple fiber product prepared by the preparation method. According to the method, two color changes under thermal stimulation and solvent stimulation of primary-color polyester fibers can be achieved, meanwhile, the tracing germanate fluorescent particles and the metal oxide tracing particles are added to make up for the defect that color changes are difficult to recognize after the fibers are dyed, and meanwhile the tracing means is complicated, so that the fibers are difficult to counterfeit.

Description

Technical Field

[0001] This invention relates to the field of recycled synthetic fiber technology, and in particular to a method and product for preparing traceable polyester staple fiber. Background Technology

[0002] The resource recycling of waste PET materials has powerfully promoted the sustainable development of social production, saving resources while reducing environmental pollution. In Europe and America, using a certain proportion of recycled materials in the production of consumer goods has become a fashionable trend. However, problems such as inconsistent quality of recycled PET plastics, opaque recycling channels, and a lack of standardized technical standards also exist. Furthermore, since recycled PET products are almost indistinguishable from those using virgin materials, yet cost more, virgin materials have been used to replace recycled materials to meet market demand. Therefore, how to implement effective traceability measures has become an urgent problem to be solved. Adding traceability agents to materials to track the production process and usage of recycled PET in finished products can effectively solve problems such as the sale of inferior or counterfeit products in the recycled PET industry, protecting corporate interests and improving corporate reputation.

[0003] Currently, commonly used anti-counterfeiting and traceability methods for PET and common fibers include adding tracers, fluorescent masterbatches, and elemental masterbatches. There are many types of common tracers, but their effects are limited; fluorescent particles can emit different colors of light at specific wavelengths, but common fluorescent particle preparation methods are transparent, and using fluorescent particles alone as a traceability and anti-counterfeiting method is easily identifiable and counterfeited; adding single-element masterbatches also presents the problem of being easily identified and counterfeited.

[0004] In summary, it is urgent to develop a simple and easy-to-implement method for preparing traceable recycled polyester staple fiber that has multiple anti-counterfeiting and traceability identification modes and is difficult to counterfeit. Summary of the Invention

[0005] This invention addresses some shortcomings in current anti-counterfeiting and traceability technologies for recycled PET fibers by providing a method for preparing traceable recycled short fibers.

[0006] The preparation method provided by this invention can achieve color change and light emission response of fibers through external stimulation. At the same time, a metal oxide is added to increase the complexity of anti-counterfeiting. This effectively improves the current problems of single traceability inspection methods and easy counterfeiting, and can achieve good anti-counterfeiting and traceability effects.

[0007] A method for preparing traceable recycled polyester staple fiber, the method comprising: preparing traceable recycled polyester staple fiber by mixing tracer particles with recycled PET in a molten state, the traceable recycled polyester staple fiber exhibiting unique color change and luminescence phenomena after being stimulated by specific temperature, solvent and ultraviolet irradiation, and the presence of specific elements and proportions of metal oxides can be detected by elemental qualitative and quantitative analysis.

[0008] A method for preparing traceable polyester staple fiber includes: mixing a tracer material with a renewable synthetic fiber material, and melt spinning to prepare the traceable renewable polyester staple fiber, wherein the tracer material includes at least two of cobalt Prussian blue analogues, germanate fluorescent materials, and metal oxides.

[0009] Preferably, the tracer material includes cobalt Prussian blue analogues and germanate fluorescent materials.

[0010] As a further preferred option, the tracer material includes cobalt Prussian blue analogues, germanate fluorescent materials, and metal oxides.

[0011] Based on some specific aspects of this experiment, the raw materials for preparing traceable recycled polyester staple fibers include recycled PET raw materials, and one or more selected from cobalt Prussian blue analogues, germanate fluorescent materials, and metal oxide tracer particles. Specifically, the cobalt Prussian blue analogues are prepared via a solution method; the germanate fluorescent materials are prepared via a high-temperature solid-state method; and the metal oxides include common metal oxides.

[0012] As one possible implementation, the preparation method of the cobalt Prussian blue analogue is as follows: using cobalt acetate tetrahydrate, potassium cobalt cyanide, and sodium citrate as raw materials, the three are prepared into a solution and then mixed. A reaction occurs between the three to form coordination bonds, resulting in a coordination compound. After stirring and allowing the reaction to proceed fully, the mixture is centrifuged, washed, and dried to obtain the cobalt Prussian blue analogue. This material can achieve a significant color-changing effect, and the compound type is difficult to determine by ash content analysis.

[0013] Furthermore, the mass ratio of cobalt acetate tetrahydrate, potassium cobalt cyanide, and sodium citrate is (1-2):1:(1-2).

[0014] Furthermore, in the preparation of the cobalt Prussian blue analogue, deionized water is used as the solvent, and solutions are prepared separately and then mixed. The reaction time is 20–60 min. The reaction time is 15–25 hours.

[0015] As one possible implementation, the method for preparing the tracer germanate fluorescent particles involves mixing and grinding a certain proportion of Na₂CO₃, CaCO₃, GeO₂, PbO, and Tb₄O₇, followed by high-temperature sintering, pulverization, and sieving to obtain the tracer germanate fluorescent particles. Germanate materials can withstand temperature changes and exhibit multiple luminescence phenomena under ultraviolet light irradiation.

[0016] Furthermore, the mass ratio of Na2CO3, CaCO3, GeO2, PbO, and Tb4O7 is (45-60):(45-55):(90-110):1:(1.5-3).

[0017] Further, the particles are sieved through a 1000-1500 mesh sieve (more preferably 1100-1300 mesh) to obtain the tracer germanate fluorescent particles.

[0018] Furthermore, the high-temperature sintering temperature is 850–1050 degrees Celsius, and the calcination time is 3–10 hours. More preferably, the high-temperature sintering temperature is 850–950 degrees Celsius, and the calcination time is 5–7 hours.

[0019] According to some preferred aspects of the present invention, the metal oxide is a common metal oxide. The metal oxide is a non-toxic metal oxide. Preferably, the metal oxide includes one or more of titanium oxide, zinc oxide, aluminum oxide, magnesium oxide, iron oxide, and calcium oxide.

[0020] This invention uses metal oxides as tracer particles, and by considering the amount added, it is an effective and low-cost method.

[0021] According to some preferred aspects of the invention, the average particle size of the metal oxide is 150-850 nm.

[0022] The method of this invention can be applied not only to the preparation of recycled polyester fibers, but also to recycled nylon fibers, recycled spandex fibers, and other recycled synthetic fibers. Preferably, the raw materials for the renewable synthetic fibers are selected from recycled PET bottle flakes, waste nylon, waste spandex, and other materials.

[0023] According to some preferred aspects of the invention, the amount of cobalt Prussian blue analogue added to the traceable recycled polyester staple fiber is 0.05wt%-0.1wt%; the amount of germanate fluorescent particles added is 0.05wt%-0.1wt%; and the amount of metal oxide added is 0.001wt%-0.05wt%. This ratio allows for a balance between anti-counterfeiting effectiveness and production cost.

[0024] A traceable polyester staple fiber is prepared by the preparation method described in any of the above technical solutions.

[0025] Furthermore, a traceable recycled polyester staple fiber is prepared by adding tracer cobalt Prussian blue analog particles, germanate fluorescent particles and metal oxides obtained from the above technical solution into recycled PET raw materials (such as recycled PET bottle flakes) for melt spinning to prepare traceable recycled polyester staple fiber.

[0026] Furthermore, a traceable recycled polyester staple fiber is prepared by mixing cobalt Prussian blue analogue, germanate fluorescent particles, metal oxides and recycled PET raw materials and adding them to a twin-screw extruder for melt spinning to prepare traceable recycled polyester staple fiber.

[0027] This invention uses Prussian blue analogues and germanate fluorescent materials as tracer particles. The Prussian blue analogues and germanate fluorescent materials are prepared by solution method and high-temperature solid-state sintering method, which are simple and convenient and do not involve complicated processes.

[0028] The method for preparing recycled polyester staple fiber using the present invention has the following advantages compared to existing anti-counterfeiting and traceability technologies:

[0029] This invention prepares and uses three types of high-temperature resistant tracer particles: cobalt Prussian blue analogue, germanate fluorescent particles, and metal oxides. These particles are added during the spinning stage of recycled polyester. All three types of particles are at the nano and micron scales, and their addition has little impact on fiber properties. Furthermore, the cost of synthesizing the tracer particles is relatively low.

[0030] This invention provides a method for preparing traceable polyester staple fiber, which can achieve two color changes of undyed polyester fiber under thermal and solvent stimulation. At the same time, tracer germanate fluorescent particles and metal oxide tracer particles are added to compensate for the difficulty in identifying color changes after fiber dyeing, and also to complicate the traceability method to make it difficult to counterfeit.

[0031] By comparing the prepared traceable recycled polyester without tracer particles with the traceable recycled polyester in off-white color with tracer particles, when the temperature rises to 110℃, the original-color traceable recycled polyester undergoes a color change from white to blue, and turns purple upon contact with ethanol solvent, which is attributed to the effect of a cobalt Prussian blue analogue. Furthermore, during ash content testing, the cobalt Prussian blue analogue turns black and becomes ineffective at a certain temperature, making the tracer particles difficult to separate and counterfeit. When irradiated with a 254nm ultraviolet lamp, the fluorescent particles in the traceable recycled polyester emit a bluish light. Simultaneously, a metal oxide is added to increase the complexity of anti-counterfeiting measures. The detection of these metal oxide tracer particles can be performed quantitatively and qualitatively using inductively coupled plasma spectrometry (ICP-PFS). Therefore, the traceable recycled polyester prepared by this invention can achieve traceability through various simple external stimuli, and the complex tracer system makes it difficult to counterfeit. Detailed Implementation

[0032] To better illustrate some key points of the specific preparation of this invention, the following examples will provide a detailed explanation.

[0033] Example 1: Preparation of tracer particles, cobalt Prussian blue analogue

[0034] 1. Using cobalt acetate tetrahydrate, potassium cobalt cyanide, and sodium citrate as raw materials, all of which are analytical grade, the three are prepared into solutions in a ratio of 14:12:21 (by weight) with deionized water as solvent, and then mixed together.

[0035] 2. After stirring the mixed solution for 30 minutes, the mixture was allowed to react for 18 hours to form a precipitate. The precipitate was then centrifuged, washed, and dried to obtain a cobalt Prussian blue analogue.

[0036] Example 2: Preparation of tracer germanate fluorescent particles

[0037] 1. Mix Na2CO3, CaCO3, GeO2, PbO, and Tb4O7 in a ratio of 53:50:104:1:2.4 and grind for 1 hour.

[0038] 2. Subsequently, germanate fluorescent particles were obtained by sintering at 950 degrees Celsius for 6 hours, crushing, and passing through a 1200-mesh sieve.

[0039] Example 3: Preparation of pure recycled polyester staple fiber

[0040] Recycled polyester staple fiber was prepared by melt spinning using pure recycled PET bottle flakes as raw material, as a comparative example.

[0041] Example 4: Preparation of Traceable Recycled Polyester Staple Fiber

[0042] 1. The tracer particles cobalt Prussian blue analog prepared in Example 1, the tracer germanate fluorescent particles prepared in Example 2, and calcium oxide were added to the spinning of recycled PET bottle flakes. The amount of cobalt Prussian blue analog added to the mixture of tracer particles and recycled PET bottle flakes was 5000 mg / kg, the amount of tracer germanate fluorescent particles was 1000 mg / kg, and the amount of calcium oxide was 20 mg / kg.

[0043] 2. Traceable recycled polyester staple fiber is prepared by melt spinning a mixture of tracer particles and recycled PET bottle flakes as raw material.

[0044] Example 5: Preparation of Traceable Recycled Polyester Staple Fiber

[0045] 1. The tracer particles cobalt Prussian blue analog prepared in Example 1, the tracer germanate fluorescent particles prepared in Example 2, and zinc oxide were added to the spinning of recycled PET bottle flakes. The amount of cobalt Prussian blue analog added to the mixture of tracer particles and recycled PET particles was 6000 mg / kg, the amount of tracer germanate fluorescent particles was 900 mg / kg, and the amount of zinc oxide was 20 mg / kg.

[0046] 2. Traceable recycled polyester staple fiber is prepared by melt spinning a mixture of tracer particles and recycled PET bottle flakes as raw material.

[0047] Example 6: Preparation of Traceable Recycled Polyester Staple Fiber

[0048] 1. The tracer particles cobalt Prussian blue analog prepared in Example 1, the tracer germanate fluorescent particles prepared in Example 2, and iron oxide were added to the spinning of recycled PET bottle flakes. The amount of cobalt Prussian blue analog added to the mixture of tracer particles and recycled PET bottle flakes was 7000 mg / kg, the amount of tracer germanate fluorescent particles was 800 mg / kg, and the amount of iron oxide was 20 mg / kg.

[0049] 2. Traceable recycled polyester staple fiber is prepared by melt spinning a mixture of tracer particles and recycled PET bottle flakes as raw material.

[0050] Example 7: Preparation of Traceable Recycled Polyester Staple Fiber

[0051] 1. The tracer particles cobalt Prussian blue analog prepared in Example 1, the tracer germanate fluorescent particles prepared in Example 2, and alumina were added to the spinning of recycled PET bottle flakes. The amount of cobalt Prussian blue analog added to the mixture of tracer particles and recycled PET bottle flakes was 8000 mg / kg, the amount of tracer germanate fluorescent particles was 700 mg / kg, and the amount of alumina was 20 mg / kg.

[0052] 2. Traceable recycled polyester staple fiber is prepared by melt spinning a mixture of tracer particles and recycled PET bottle flakes as raw material.

[0053] Example 8: Preparation of Traceable Recycled Polyester Staple Fiber

[0054] 1. The tracer particles cobalt Prussian blue analog prepared in Example 1, the tracer germanate fluorescent particles prepared in Example 2, and titanium dioxide were added to the spinning of recycled PET bottle flakes. The amount of cobalt Prussian blue analog added to the mixture of tracer particles and recycled PET bottle flakes was 9000 mg / kg, the amount of tracer germanate fluorescent particles was 600 mg / kg, and the amount of titanium dioxide was 20 mg / kg.

[0055] 2. Traceable recycled polyester staple fiber is prepared by melt spinning a mixture of tracer particles and recycled PET bottle flakes as raw material.

[0056] Example 9: Preparation of Traceable Recycled Polyester Staple Fiber

[0057] 1. The tracer particles cobalt Prussian blue analog prepared in Example 1, the tracer germanate fluorescent particles prepared in Example 2, and magnesium oxide were added to the spinning of recycled PET bottle flakes. The amount of cobalt Prussian blue analog added to the mixture of tracer particles and recycled PET bottle flakes was 10000 mg / kg, the amount of tracer germanate fluorescent particles was 500 mg / kg, and the amount of magnesium oxide was 20 mg / kg.

[0058] 2. Traceable recycled polyester staple fiber is prepared by melt spinning a mixture of tracer particles and recycled PET bottle flakes as raw material.

[0059] Example 10: Detection of Traceable Recycled Polyester Staple Fibers

[0060] 1. Using a multi-point sampling method, the traceable recycled polyester staple fibers prepared in Examples 4-9 were tested for luminescence and color rendering using a fluorescence colorimeter and a halogen tungsten lamp. When irradiated with 254nm ultraviolet light for 3 minutes, the fluorescent particles in the fiber emitted a bluish light, and the afterglow was green light.

[0061] 2. Irradiate the recycled polyester staple fiber prepared in Example 3 without tracer particles for 3 minutes, and compare it with the traceable recycled polyester staple fiber in Examples 4-9. The fiber without tracer particles showed no change. In Examples 4-9, as the tracer germanate fluorescent particles increased, the number of luminescent points in the fiber increased and the luminescence effect gradually increased.

[0062] 3. If ash content analysis is to be performed, the color-changing particles in the example will turn black and become ineffective due to high temperature, making it impossible to identify each component through ash content analysis, thus making the product difficult to imitate.

[0063] Example 11: Detection of Traceable Recycled Polyester Staple Fibers

[0064] 1. Using a multi-point sampling method, the traceable recycled polyester staple fibers prepared in Examples 3-9 were heated to 110°C for observation. The prepared traceable off-white recycled polyester staple fibers showed a blue change.

[0065] 2.1 At 110°C, the recycled polyester staple fiber prepared in Example 3 without tracer particles was compared with the traceable polyester staple fiber in Examples 4-9. The fiber without tracer particles showed no change, while the fiber in Examples 4-9 became darker blue with the increase of cobalt Prussian blue analogue additive.

[0066] 3. If ash content analysis is to be performed, the color-changing particles in the example will turn black and become ineffective due to high temperature, making it impossible to identify each component through ash content analysis, thus making the product difficult to imitate.

[0067] Example 12: Detection of Traceable Recycled Polyester Staple Fibers

[0068] 1. Using a multi-point sampling method, the traceable recycled polyester staple fibers prepared in Examples 4-9 were placed in anhydrous ethanol solvent for 5 minutes, and the fibers showed a purple color change.

[0069] 2. Under anhydrous ethanol stimulation conditions, the recycled polyester staple fiber prepared in Example 3 without tracer particles was compared with the traceable polyester staple fiber in Examples 4-9. The fiber without tracer particles showed no change, while the fiber in Examples 4-9 became darker purple with the increase of cobalt Prussian blue analogue additive.

[0070] 3. If ash content analysis is to be performed, the color-changing particles in the example will turn black and become ineffective due to high temperature, making it impossible to identify each component through ash content analysis, thus making the product difficult to imitate.

[0071] Example 13: Detection of Traceable Recycled Polyester Staple Fibers

[0072] 1. Using a multi-point sampling method, inductively coupled plasma atomic emission spectrometry was used to perform elemental quantitative and qualitative analysis on the traceable recycled polyester staple fibers prepared in Examples 3-9. Calcium oxide 20 mg / kg, zinc oxide 20 mg / kg, iron oxide 20 mg / kg, aluminum oxide 20 mg / kg, titanium oxide 20 mg / kg, and magnesium oxide 20 mg / kg were detected in the traceable recycled polyester staple fibers prepared in Examples 4-9, respectively.

[0073] 2. The recycled polyester staple fiber prepared in Example 3 without tracer particles was compared with the traceable polyester staple fiber in Examples 4-9. Metal ions were detected in the fiber prepared in Example 3 without tracer particles, while calcium oxide, zinc oxide, iron oxide, aluminum oxide, titanium oxide, and magnesium oxide were detected in the traceable recycled polyester staple fiber prepared in Examples 4-9, respectively.

[0074] In addition, the polyester staple fiber obtained in Example 3 and the traceable recycled polyester staple fiber obtained in Examples 4-9 of this invention were subjected to comprehensive performance testing using GB / T 14337-2022 and GB / T 14464-2017 standards. The test results for the polyester staple fiber product obtained in Example 3 were as follows: fiber breaking strength: 4.2 cN / dtex; dyeing uniformity: grade 4; tensile breaking strength: 7%. The test results for the traceable recycled polyester staple fiber obtained in Examples 4-9 were as follows: fiber breaking strength: 4.1 cN / dtex; dyeing uniformity: grade 4; tensile breaking strength: 7%. These results are comparable to the mechanical strength of polyester fiber without the tracer, demonstrating that the addition of the tracer in this invention does not affect the overall comprehensive performance of the product.

Claims

1. A method for producing traceable polyester staple fiber, characterized by, The application relates to a traceable polyester staple fiber and a preparation method thereof. The traceable raw material is mixed with the recycled PET raw material to prepare the traceable recycled polyester staple fiber through melt spinning, and the traceable raw material comprises at least two of cobalt Prussian blue analogues, germanate fluorescent materials and metal oxides.

2. The method of claim 1, wherein the method is characterized by, The cobalt Prussian blue analogues are added in an amount of 0.05wt%-1wt% in the traceable polyester staple fiber; the germanate fluorescent materials are added in an amount of 0.05wt%-0.1wt%; and the metal oxides are added in an amount of 0.001wt%-0.05wt%.

3. The method of claim 1, wherein the method is characterized by, The cobalt Prussian blue analogues are prepared through a solution method: cobalt acetate tetrahydrate, potassium cobalt cyanide and sodium citrate are used as raw materials, a solution is prepared by mixing the three, a coordination bond is generated among the three, a coordination compound is formed, and the cobalt Prussian blue analogues are obtained through post-processing.

4. The method for preparing traceable polyester staple fiber according to claim 3, characterized in that, The mass ratio of the cobalt acetate tetrahydrate, the potassium cobalt cyanide and the sodium citrate is (1-2):1:(1-2).

5. The method of claim 1, wherein the method is characterized by, The preparation method of the germanate fluorescent material is as follows: Na2CO3, CaCO3, GeO2, PbO and Tb4O7 are mixed and ground, and then traceable germanate fluorescent particles are obtained through high-temperature sintering, crushing and sieving.

6. The method for preparing traceable polyester staple fiber according to claim 5, characterized in that, The mass ratio of the Na2CO3, the CaCO3, the GeO2, the PbO and the Tb4O7 is (45-65):(40-60):(90-110):1:(1.5-3.5).

7. The method of claim 1, wherein the method is characterized by, The metal oxides comprise one or more of titanium oxide, zinc oxide, aluminum oxide, magnesium oxide, iron oxide and calcium oxide.

8. The method for preparing traceable polyester staple fiber according to claim 1, characterized in that, The average particle size of the metal oxides is 150-850nm.

9. The method for preparing traceable polyester staple fiber according to claim 1, characterized in that, The method can be applied to recycled polyurethane fibers, recycled nylon fibers and recycled synthetic fibers.

10. A traceable polyester staple fiber, characterized by, The method is prepared according to any one of claims 1-9.