Liquid guide medium and preparation method thereof

Abstract

The invention discloses a liquid guide medium and a preparation method thereof, the liquid guide medium comprises polyimide fibers and polyphthalamide fibers, and the polyimide fibers and the polyphthalamide fibers are mutually entangled. The liquid guide medium is good in temperature resistance, high in breaking strength, large in elastic modulus and high in consistency in the assembling and forming process.

Description

Technical Field

[0001] The present application relates to the field of atomization technology, and in particular to a liquid-conducting medium and a preparation method thereof. Background Art

[0002] The electronic atomization device includes an atomization core and a liquid-conducting medium covering the surface of the atomization core. The liquid-conducting medium transfers the atomization matrix to the atomization core, and the atomization core atomizes the atomization matrix.

[0003] The existing oil-conducting medium generally adopts a blended material of flax fiber and cotton. The liquid-conducting medium prepared in this way has certain disadvantages: the liquid-conducting medium has poor temperature resistance and is easily carbonized during heating, thus affecting the suction experience; the liquid-conducting medium has low breaking strength, small elastic modulus, and poor consistency during assembly and molding. Summary of the invention

[0004] The main purpose of the present application is to provide a liquid conducting medium and a preparation method thereof, so as to solve the technical problems of low fracture strength, small elastic modulus and poor consistency of the existing liquid conducting medium.

[0005] To achieve the above-mentioned purpose, the present application provides a liquid-conducting medium in a first aspect, wherein the liquid-conducting medium comprises:

[0006] Polyimide fibers; and

[0007] Polyphthalamide fiber;

[0008] Wherein, the polyimide fiber and the polyphthalamide fiber are entangled with each other.

[0009] Optionally, the mass fraction of the polyimide fiber is greater than or equal to 30% and less than or equal to 50%; the mass fraction of the polyphthalamide fiber is greater than or equal to 50% and less than or equal to 70%.

[0010] Optionally, the polyimide fiber has a length of 20 to 100 mm, a diameter of 0.5 to 5 dtex, and a density of 1.25 to 1.4 g / cm 3 , tensile strength of 0.5-1.5 Gpa, elastic modulus of 20-50 Gpa, decomposition temperature of 500-600°C; the polyphthalamide fiber has a length of 20-100 mm, a diameter of 0.5-5 dtex, and a density of 1.15-1.3 g / cm 3 , tensile strength is 50-100Mpa, elastic modulus is 1-5Gpa, and decomposition temperature is 250-350℃.

[0011] The second aspect of the present application provides a method for preparing a liquid-conducting medium, the method for preparing the liquid-conducting medium comprising the steps of:

[0012] Pre-treat the polyimide fiber and the polyphthalamide fiber;

[0013] Open and mix, where the ratio of the linear speed of the beater to the linear speed of the feed roller is 0.8:1 to 2.5:1;

[0014] Card and form a web, where the rotational speed of the cylinder is 600 - 1500 rpm and the tooth density of the cylinder card clothing is 20 - 40 teeth per square inch;

[0015] Cross-lay the web, where the CV value of the weight uniformity controlled by the controller is ≤3%, the ratio of the fiber orientation degree MD to the fiber orientation degree CD is 1.2 - 1.4, and the controlled product weight is 30 - 150 gsm;

[0016] Hydroentangle for reinforcement, where the pressure in the pre-wetting zone is 0.5 - 2 Mpa, the pressure in the hydroentangling zone is 5 - 20 Mpa, the number of hydroentangling heads is 6 - 10, the aperture of the pinholes is 0.05 - 0.25 mm, and the density of the pinholes is 16 - 24 holes / cm;

[0017] Dehydrate and dry.

[0018] Optionally, the pre-treatment of the polyimide fiber and the polyphthalamide fiber includes a hydrophilization treatment, and the hydrophilization treatment includes the steps of: putting the polyimide fiber and the polyphthalamide fiber into a NaOH solution and stirring for 1 - 10 min, where the mass fraction of the NaOH solution is 20 - 40%; cleaning; drying, where the drying temperature is 50 - 120 °C.

[0019] Optionally, the hydrophilization treatment further includes the step of: heating the NaOH solution to 50 - 90 °C.

[0020] Optionally, in the step of opening and mixing, a carding beater is used, the diameter of the beater is 200 - 380 mm, the rotational speed of the beater is 500 - 1100 rpm, and the speed of the feed roller is 1.0 - 2.3 m / min.

[0021] Optionally, in the step of carding and forming a web, the ratio of the rotational speed of the cylinder working roller to the rotational speed of the cylinder stripper roller can be 1:1.2 - 1:1.5.

[0022] Optionally, the pressure of the main hydroentangling head in the hydroentangling zone is 5 - 20 Mpa.

[0023] Optionally, the hydroentangling fixation further includes the step of: hydroentangling the front and back sides alternately.

[0024] In the liquid guiding medium of the present application, the liquid guiding medium includes polyimide fibers and polyphthalamide fibers. The polyimide fibers and polyphthalamide fibers are mixed and woven. The liquid guiding medium has good heat resistance, high breaking strength, high elastic modulus and high consistency during assembly and molding.

[0025] Through the preparation method of the liquid guiding medium of the present application, a liquid guiding medium with good heat resistance, high breaking strength, high elastic modulus and high consistency during assembly and molding can be prepared. Description of the Drawings

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the structures shown in these drawings.

[0027] Figure 1 It is a product diagram of an embodiment of the liquid guiding medium of the present application;

[0028] Figure 2 It is Figure 1 a schematic diagram of the illustrated embodiment;

[0029] Figure 3 It is a flowchart of the preparation method of the liquid guiding medium of the present application.

[0030] Explanation of the Reference Numerals in the Drawings:

[0031] Label Name Label Name 100 Liquid guiding medium 110 Polyimide fiber 120 Polyphthalamide fiber

[0032] The realization of the purpose, functional features and advantages of the present application will be further described in conjunction with the embodiments and with reference to the drawings. Detailed Embodiments

[0033] The following will clearly and completely describe the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, rather than all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present application.

[0034] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present application are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the drawings). If the specific posture changes, the directional indications will also change accordingly.

[0035] In addition, the descriptions involving "first", "second", etc. in this application are for descriptive purposes only, and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, "and / or" throughout the text includes three scenarios. Taking A and / or B as an example, it includes the technical solution of A, the technical solution of B, and the technical solution where both A and B are satisfied simultaneously. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on what can be achieved by those of ordinary skill in the art. When the combination of technical solutions results in contradictions or cannot be achieved, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0036] Please refer to Figure 1 and Figure 2 , this application provides a liquid guiding medium 100, which includes polyimide fiber (Polyimide, PI) 110 and polyphthalamide fiber (Polyphthalamide, PPA) 120, and the polyimide fiber 110 and the polyphthalamide fiber 120 are mixed and woven. The liquid guiding medium 100 of this application has good heat resistance, high breaking strength, high elastic modulus and high consistency during the assembly and molding processes. The density of the liquid guiding medium of this application is greater than or equal to 0.05 g / cm 3 , and less than or equal to 0.3 g / cm 3 , and the density of the liquid guiding medium can be adjusted according to actual needs.

[0037] Polyimide fiber is a type of polymer with an imide ring (-CO-NR-CO-) in the main chain, and it is one of the organic polymer materials with the best comprehensive performance. In the liquid guiding medium of this application, the mass fraction of polyimide fiber can be greater than or equal to 30% and less than or equal to 50%. Further, the mass fraction of polyimide fiber is 30 - 35%, 40 - 50%, 32 - 45%, 45 - 50%, 35 - 48% and any range within the above ranges or between any two of the above ranges. Even further, the mass fraction of polyimide fiber is 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50% or any value between any two of the above values.

[0038] The length of the polyimide fiber can be greater than or equal to 20 mm and less than or equal to 100 mm. The diameter of the polyimide fiber can be greater than or equal to 0.5 dtex and less than or equal to 5 dtex. The density of the polyimide fiber can be greater than or equal to 1.25 g / cm 3and less than or equal to 1.4 g / cm 3 The tensile strength of the polyimide fiber can be greater than or equal to 0.5 GPa and less than or equal to 1.5 GPa. Thus, the liquid guiding medium prepared from the polyimide fiber has a relatively high tensile strength. The elastic modulus of the polyimide fiber can be greater than or equal to 20 GPa and less than or equal to 50 GPa. Thus, the liquid guiding medium prepared from the polyimide fiber has a relatively appropriate elastic modulus. The decomposition temperature of the polyimide fiber can be greater than or equal to 500 °C and less than or equal to 600 °C. Thus, the liquid guiding medium prepared from the polyimide fiber has relatively good temperature resistance.

[0039] The polyphthalamide fiber is a high-performance aromatic fiber, and its main component is PA nylon. In the liquid guiding medium of the present application, the mass fraction of the polyphthalamide fiber can be greater than or equal to 50% and less than or equal to 70%. Further, the mass fraction of the polyphthalamide fiber can be 50 - 65%, 50 - 60%, 52 - 65%, 55 - 70%, 55 - 58%, and any range within the above ranges or between any two of the above ranges. Even further, the mass fraction of the polyphthalamide fiber can be 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, or any value between any two of the above values.

[0040] The length of the polyphthalamide fiber can be greater than or equal to 20 mm and less than or equal to 100 mm. The length of the polyphthalamide fiber can be the same as or different from the length of the polyimide fiber. The diameter of the polyphthalamide fiber can be greater than or equal to 0.5 dtex and less than or equal to 5 dtex. The diameter of the polyphthalamide fiber can be the same as or different from the diameter of the polyimide fiber. The density of the polyphthalamide fiber can be greater than or equal to 1.15 g / cm 3 and less than or equal to 1.3 g / cm 3 The tensile strength of the polyphthalamide fiber can be greater than or equal to 50 Mpa and less than or equal to 100 Mpa. Thus, the liquid guiding medium prepared from the polyphthalamide fiber has a relatively high tensile strength. The elastic modulus of the polyphthalamide fiber can be greater than or equal to 1 GPa and less than or equal to 5 GPa. Thus, the liquid guiding medium prepared from the polyphthalamide fiber has a relatively appropriate elastic modulus. The decomposition temperature of the polyphthalamide fiber can be greater than or equal to 250 °C and less than or equal to 350 °C. Thus, the liquid guiding medium prepared from the polyimide fiber has relatively good temperature resistance.

[0041] The present application provides a method for preparing a liquid guiding medium, and the preparation method adopts a hydrospinning process. The hydrospinning process is a physical manufacturing process that uses high-pressure water jets to spray a fiber web, causing the fibers to entangle with each other to form a non-woven fabric. The hydrospinning process entangles the fibers naturally through water flow, without the need for chemical binders. The product is non-irritating to the human body and is suitable for use in electronic atomization devices; the fibers form a three-dimensional entangled structure under the impact of water flow, with balanced longitudinal and transverse strengths, good tensile resistance and tear resistance, and good surface uniformity of the fabric, and it is not easy to have holes or weak points; the product has good air permeability and strong absorption and conduction capabilities for the atomization matrix.

[0042] Please refer to Figure 3 , the preparation method of the liquid guiding medium of the present application includes the steps: S100, pre-treating polyimide fibers and polyphthalamide fibers; S200, opening and mixing; S300, carding into a web; S400, cross-laying; S500, hydrospinning reinforcement; S600, dewatering and drying.

[0043] Specifically, S100, pre-treating polyimide fibers and polyphthalamide fibers includes a hydrophilic treatment. The hydrophilic treatment can reduce the crystallinity of polyimide fibers and polyphthalamide fibers, increase the microporous structure on the surface and improve the specific surface area, thereby increasing the hydrophilic properties of the two.

[0044] The hydrophilic treatment includes the steps: S110, putting polyimide fibers and polyphthalamide fibers into a NaOH solution and stirring for 1 to 10 minutes; S120, cleaning; S130, drying. In S110, the mass fraction of the NaOH solution can be 20 to 40%. In S120, it can be washed with warm water in multiple cycles to remove the solution remaining on the fiber surface. In S130, the fibers can be dried in an oven to remove excess moisture, and the oven temperature can be 50 - 120°C.

[0045] The hydrophilic treatment may further include the step: S140, heating the NaOH solution to 50 - 90°C. By doing so, the efficiency and uniformity of the hydrophilic treatment can be improved. The order of S140 can be before S110, or between S110 and S120. When the temperature of the NaOH solution is relatively high, the stirring time can be shortened, and when the temperature of the NaOH solution is relatively low, the stirring time can be extended.

[0046] S200. Opening and blending is a key step in the pretreatment of fiber raw materials, directly affecting the quality of subsequent carding, web laying, and hydroentangling. In the opening and blending step, the fiber raw materials are loosened by an opener, impurities are removed, and different fibers are mixed in proportion. After opening, the fibers can be preliminarily sorted to make them preliminarily oriented, facilitating subsequent processes. The synergistic effect of the beater and the feed roller is the core of the opening and blending process. For opening, a carding beater can be used. The carding beater strikes gently, and "using carding instead of beating" can reduce fiber damage. The diameter of the beater can be 200 - 380 mm, the rotational speed of the beater can be 500 - 1100 rpm, the speed of the feed roller can be 1.0 - 2.3 m / min, and the ratio of the linear speed of the carding beater to the linear speed of the feed roller can be 0.8:1 - 2.5:1.

[0047] S300. Carding and web forming is a key process that further loosens the fibers after opening and blending into single fibers, evenly distributes them, and forms a continuous fiber web, directly affecting the structural uniformity of the fiber web, fiber orientation, and subsequent hydroentangling effect. In the S300. Carding and web forming step, the fibers are further carded by a carding machine to make them fully dispersed and form a uniform single-layer fiber web (fiber web), and the fibers are randomly or oriented. The cylinder can drive the fibers to rub against the card clothing to achieve the separation of single fibers. Among them, the rotational speed of the cylinder can be 600 - 1500 rpm, the tooth density of the cylinder card clothing can be 20 - 40 teeth per inch², and the ratio of the rotational speed of the cylinder working roller to the rotational speed of the cylinder stripping roller can be 1:1.2 - 1:1.5.

[0048] S400. Cross-laying is a key process that cross-laminates the single-layer fiber web after carding through a web laying device to form a fiber layer with a certain thickness and balanced longitudinal and transverse strength. In the actual application process, the thickness and uniformity of the grammage need to be strictly controlled, otherwise it will seriously affect the consistency of the product. Therefore, in the S400. Cross-laying step, the CV value of the grammage uniformity controlled by the controller is ≤3%, the ratio of the fiber orientation degree MD to the fiber orientation degree CD is 1.2 - 1.4, and the product grammage is controlled to be 30 - 150 gsm. Among them, MD is the direction perpendicular to the axis direction of the roller, and CD is the direction parallel to the axis direction of the roller.

[0049] S500. Hydroentangling is a key process that mechanically entangles the fiber web through high-pressure water jets to make it have specific strength, handle, and functions, and is the most core step in the hydroentangling process. The core of hydroentangling lies in achieving the balance between "reinforcement effect" and "product performance" by controlling hydroentangling energy, equipment parameters, and fiber interactions.

[0050] In the preparation method of this application, the S500. Hydroentangling step includes S510. Pre-wetting; S520. Hydroentangling treatment.

[0051] The purpose of pre-wetting is to fully moisten the fiber web, improve the flexibility of fibers and the surface friction coefficient, reduce static electricity, compact the fiber web, enable the fiber web to better absorb the energy of the water jet, and facilitate uniform stress during hydroentangling. Pre-wetting can be achieved using a roller or a spraying device. By evenly spraying warm water (20 - 50°C), the water content of the fiber web is brought to 60% - 80%. The pressure in the pre-wetting zone can be 0.5 - 2 Mpa, so that the pre-wetting is uniform and deformation of the fiber web during hydroentangling due to local over-wetting or over-drying is avoided.

[0052] In step S520, the hydroentangling process, a high-pressure water pump is used to pass water through a hydroentangling head (a metal plate covered with fine nozzles) to form a dense water needle impact on the fiber web. The water needles force the fibers in the fiber web to interpenetrate and entangle with each other. With the cooperation of a roller or a suction-type dehydration device, a preliminary fabric with a certain strength is formed. The pressure in the hydroentangling zone can be 5 - 20 Mpa, the pressure of the main hydroentangling head in the hydroentangling zone can be 5 - 20 Mpa, the number of hydroentangling heads can be 6 - 10, the aperture of the needle holes can be 0.05 - 0.25 mm, and the density of the needle holes can be 16 - 24 holes / cm. These parameters can be adjusted according to factors such as the mass per unit area of the fiber web and the production speed. The hydroentangling heads can be aligned vertically or inclined at 5 - 15° to the fiber web, and the distance between the hydroentangling heads and the mesh curtain can be 5 - 50 mm, and the distance can be adjusted in real time. At a short distance, it promotes surface reinforcement of the fibers, and at a long distance, it promotes deep entanglement of the fibers.

[0053] In step S520, the hydroentangling process, the hydroentangling can be carried out alternately on both the front and back sides. First, the front side is preliminarily entangled, the back side enhances the interlayer bonding, and then the front side modifies the surface to improve the balance of longitudinal and transverse strength. Alternate hydroentangling on the front and back sides can make the strong bonding on both sides of the fiber web closer, reduce the ratio of longitudinal and transverse tensile forces, and improve the overall strength of the product; it can eliminate the hydroentangling marks on the surface of the fiber web, making the product surface more delicate and uniform; it can also make the fibers in the fiber web entangle with each other more fully, thereby improving the hygroscopicity, softness, and adsorption capacity of the product. The hydroentangling pressure, number of times (such as 2 - 4 times), and time on both the front and back sides can be adjusted according to product requirements.

[0054] In step S520, the hydroentangling process, multi-stage hydroentangling can be adopted, and the hydroentangling pressure can be increased step by step. In this way, the initial low hydroentangling pressure can prevent the loose fiber web from breaking, and the subsequent high hydroentangling pressure can enhance the reinforcement effect.

[0055] After hydroentangling, the water content of the fiber web is as high as 90%, and most of the free water needs to be removed. In step S600, the dehydration and drying process, the excess water in the fabric after hydroentangling can be removed by vacuum suction or mechanical extrusion. Then, a hot air oven, a drum dryer, or an infrared drying device is used to reduce the moisture content of the fabric to less than 1%, and at the same time, the fiber structure is preliminarily shaped.

[0056] The preparation method further includes the steps: S700, winding and die cutting. After the qualified spunlace non-woven fabric is cooled by the cooling roller, it is wound by the winder according to the set length, and then slit, and finally the finished product is made.

[0057] The preparation method may further include the step: S800, post-treatment. The post-treatment process is a key link following the spunlace reinforcement and drying and shaping. Through physical, chemical or functional treatments, the basic properties such as water absorbency, softness, strength, air permeability, etc. of the liquid guiding medium are improved, and the shrinkage rate is controlled to ensure that the liquid guiding medium is not easily deformed during the assembly and shaping processes.

[0058] The spunlace process involves the adjustment of various fine parameters in multiple steps. This application only introduces several key parameters. The adjustment of other parameters can refer to the prior art. Based on the triangular balance of fiber characteristics, equipment capabilities, and product requirements, a parameter database is established through systematic testing, and the preparation process is optimized in real time by combining online monitoring. The items for finished product inspection can include gram weight, thickness, breaking strength, elastic modulus, appearance defects (such as holes, water needle marks), fiber distribution uniformity, etc., to ensure that the prepared products meet the standards.

[0059] Example 1

[0060] Raw materials: Polyimide fiber: mass fraction of 30%, length of 20 mm, diameter of 0.5 dtex, density of 1.25 g / cm 3 , tensile strength of 0.5 Gpa, elastic modulus of 20 Gpa, decomposition temperature of 500 °C; Polyphthalamide fiber: mass fraction of 70%, length of 20 mm, diameter of 0.5 dtex, density of 1.15 g / cm 3 , tensile strength of 50 Mpa, elastic modulus of 1 Gpa, decomposition temperature of 250 °C.

[0061] Preparation method:

[0062] (1) Heat the NaOH solution with a mass fraction of 20% to 50 °C;

[0063] (2) Put the polyimide fiber and polyphthalamide fiber into the NaOH solution and stir for 1 min;

[0064] (3) Wash with warm water in multiple cycles;

[0065] (4) Dry at 50 °C;

[0066] (5) Open and mix. The ratio of the linear speed of the carding beater to the linear speed of the feed roller is 0.8:1, the diameter of the carding beater is 200 mm, the rotational speed of the beater is 500 rpm, and the speed of the feed roller is 1 m / min;

[0067] (6) Carding into a web, the rotational speed of the cylinder is 600 rpm, the ratio of the rotational speed of the working roller to the rotational speed of the stripper roller is 1:1.2, and the tooth density of the cylinder card clothing is 20 teeth per square inch;

[0068] (7) Cross-laying, the CV value of the controller weight uniformity is ≤ 3%, the ratio of the fiber orientation degree MD to the fiber orientation degree CD is 1.2, and the control product weight is 30 gsm;

[0069] (8) Hydroentangling for reinforcement, the pressure in the pre-wetting zone is 0.5 Mpa, the pressure in the hydroentangling zone is 5 Mpa, the pressure of the main hydroentangling head in the hydroentangling zone is 5 Mpa, the number of hydroentangling heads is 6, the aperture of the needle holes is 0.05 mm, and the density of the needle holes is 16 holes / cm;

[0070] (9) Dehydration and drying.

[0071] Example 2

[0072] Raw materials: Polyimide fiber: mass fraction 50%, length 100 mm, diameter 5 dtex, density 1.4 g / cm 3 、tensile strength 1.5 Gpa, elastic modulus 50 Gpa, decomposition temperature 600 °C; Polyphthalamide fiber: mass fraction 50%, length 100 mm, diameter 5 dtex, density 1.3 g / cm 3 、tensile strength 100 Mpa, elastic modulus 5 Gpa, decomposition temperature 350 °C.

[0073] Preparation method:

[0074] (1) Heat the NaOH solution with a mass fraction of 40% to 50 °C;

[0075] (2) Put the polyimide fiber and the polyphthalamide fiber into the NaOH solution and stir for 10 min;

[0076] (3) Wash with warm water in multiple cycles;

[0077] (4) Dry at 120 °C;

[0078] (5) Opened and mixed, the ratio of the linear speed of the carding beater to the linear speed of the feed roller is 2.5:1, the diameter of the carding beater is 380 mm, the rotational speed of the beater is 1100 rpm, and the speed of the feed roller is 2.3 m / min;

[0079] (6) Carding into a web, the rotational speed of the cylinder is 1500 rpm, the ratio of the rotational speed of the working roller to the rotational speed of the stripper roller is 1:1.5, and the tooth density of the cylinder card clothing is 40 teeth per square inch;

[0080] (7) Cross-laying, the CV value of the grammage uniformity controlled by the controller is ≤ 3%, the ratio of the fiber orientation degree MD to the fiber orientation degree CD is 1.4, and the product grammage is controlled to be 150 gsm;

[0081] (8) Hydroentangling reinforcement, the pressure in the pre-wetting zone is 2 Mpa, the pressure in the hydroentangling zone is 20 Mpa, the pressure of the main hydroentangling head in the hydroentangling zone is 20 Mpa, the number of hydroentangling heads is 10, the aperture of the pinholes is 0.25 mm, and the density of the pinholes is 24 holes / cm;

[0082] (9) Dehydration and drying.

[0083] Example 3

[0084] Raw materials: Polyimide fiber: mass fraction is 40%, length is 60 mm, diameter is 3 dtex, density is 1.3 g / cm 3 、tensile strength is 1 Gpa, elastic modulus is 35 Gpa, decomposition temperature is 550 °C; Polyphthalamide fiber: mass fraction is 60%, length is 60 mm, diameter is 3 dtex, density is 1.2 g / cm 3 、tensile strength is 80 Mpa, elastic modulus is 3 Gpa, decomposition temperature is 300 °C.

[0085] Preparation method:

[0086] (1) Heat the NaOH solution with a mass fraction of 30% to 50 °C;

[0087] (2) Put the polyimide fiber and polyphthalamide fiber into the NaOH solution and stir for 5 min;

[0088] (3) Wash with warm water in multiple cycles;

[0089] (4) Dry at 80 °C;

[0090] (5) Opened and mixed, the ratio of the linear speed of the carding beater to the linear speed of the feed roller is 2:1, the diameter of the carding beater is 300 mm, the rotational speed of the beater is 800 rpm, and the speed of the feed roller is 1.8 m / min;

[0091] (6) Carded into a web, the rotational speed of the cylinder is 1000 rpm, the ratio of the rotational speed of the working roller to the rotational speed of the stripper roller is 1:1.3, and the tooth density of the cylinder card clothing is 30 teeth / inch²;

[0092] (7) Cross-laying, the CV value of the grammage uniformity controlled by the controller is ≤ 3%, the ratio of the fiber orientation degree MD to the fiber orientation degree CD is 1.3, and the product grammage is controlled to be 100 gsm;

[0093] (8) Hydroentangling reinforcement, with a pressure of 1 Mpa in the pre-wetting area, a pressure of 10 Mpa in the hydroentangling area, a pressure of 15 Mpa for the main hydroentangling head in the hydroentangling area, 8 hydroentangling heads, a pore diameter of the needle holes of 0.15 mm, and a density of the needle holes of 20 holes / cm;

[0094] (9) Dehydration and drying.

[0095] Detect and compare the temperature resistance, oil conduction ability, breaking strength, elastic modulus, consistency, and taste of the existing liquid guiding media and the liquid guiding media in the above different embodiments.

[0096] Table 1 Detection results of the existing liquid guiding media and the liquid guiding media of this application

[0097]

[0098] From the above results, it can be obtained that compared with the existing liquid guiding media, the liquid guiding media of this application has good high-temperature resistance, high breaking strength, high elastic modulus, good consistency during assembly and molding, and stable taste.

[0099] The above are only the preferred embodiments of this application, and do not limit the patent scope of this application. Any equivalent structural transformation made under the inventive concept of this application by using the content of the specification and drawings of this application, or directly / indirectly applied in other related technical fields, is included in the patent protection scope of this application.

Claims

1. A liquid guiding medium, characterized in that, Comprising: Polyimide fiber; And Polyphthalamide fiber; Wherein, the polyimide fiber and the polyphthalamide fiber are intertwined with each other.

2. The liquid guiding medium according to claim 1, wherein The mass fraction of the polyimide fiber is greater than or equal to 30% and less than or equal to 50%; the mass fraction of the polyphthalamide fiber is greater than or equal to 50% and less than or equal to 70%.

3. The liquid guiding medium according to claim 1, wherein, The length of the polyimide fiber is 20 to 100 mm, the diameter is 0.5 to 5 dtex, and the density is 1.25 to 1.4 g / cm 3 , the tensile strength is 0.5 to 1.5 Gpa, the elastic modulus is 20 to 50 Gpa, and the decomposition temperature is 500 to 600 °C; The length of the polyphthalamide fiber is 20 to 100 mm, the diameter is 0.5 to 5 dtex, and the density is 1.15 to 1.3 g / cm 3 , the tensile strength is 50 to 100 Mpa, the elastic modulus is 1 to 5 Gpa, and the decomposition temperature is 250 to 350 °C.

4. A method for preparing the liquid guiding medium according to any one of claims 1 to 3, characterized in that The preparation method includes the steps: Pre-treat the polyimide fiber and the polyphthalamide fiber; Open and mix, wherein the ratio of the linear speed of the beater to the linear speed of the feed roller is 0.8:1 to 2.5:1; Card and form a web, wherein the rotational speed of the cylinder is 600 - 1500 rpm, and the tooth density of the cylinder card clothing is 20 - 40 teeth per square inch; Cross-lay the web, wherein the CV value of the weight uniformity controlled by the controller is ≤ 3%, the ratio of the fiber orientation degree MD to the fiber orientation degree CD is 1.2 - 1.4, and the controlled product weight is 30 - 150 gsm; Needle-punch and reinforce, wherein the pressure in the pre-wetting zone is 0.5 - 2 Mpa, the pressure in the needle-punch zone is 5 - 20 Mpa, the number of needle-punch heads is 6 - 10, the aperture of the needle holes is 0.05 - 0.25 mm, and the density of the needle holes is 16 - 24 holes / cm; Dehydrate and dry.

5. The preparation method of the liquid guiding medium according to claim 4, characterized in that, The pre-treatment of the polyimide fiber and the polyphthalamide fiber includes a hydrophilization treatment, and the hydrophilization treatment includes the steps: Put the polyimide fiber and the polyphthalamide fiber into a NaOH solution and stir for 1 - 10 min, wherein the mass fraction of the NaOH solution is 20 - 40%; Wash; Dry, wherein the drying temperature is 50 - 120 °C.

6. The preparation method of the liquid guiding medium according to claim 5, characterized in that, The hydrophilization treatment further includes the steps: Heat the NaOH solution to 50 - 90 °C.

7. The preparation method of the liquid guiding medium according to claim 4, wherein, In the step of opening and mixing, a comb-type beater is used, the diameter of the beater is 200 - 380 mm, the rotational speed of the beater is 500 - 1100 rpm, and the speed of the feed roller is 1.0 - 2.3 m / min.

8. The preparation method of the liquid guiding medium according to claim 4, characterized in that, In the step of carding and forming a web, the ratio of the rotational speed of the cylinder working roller to the rotational speed of the cylinder stripping roller can be 1:1.2 - 1:1.

5.

9. The preparation method of the liquid guiding medium according to claim 4, characterized in that, The pressure of the main needle-punch head in the needle-punch zone is 5 - 20 Mpa.

10. The preparation method of the liquid guiding medium according to claim 4, characterized in that, The needle-punch fixation further includes the steps: Needle-punch alternately on both the front and back sides.

Images