High-temperature-resistant flame-retardant ultra-high molecular weight polyethylene composite yarn and preparation method thereof

Abstract

The invention relates to a high-temperature resistant and flame-retardant ultra-high molecular weight polyethylene composite yarn and a preparation method thereof. The composite yarn of the invention adopts a special high-temperature resistant and spinning process, and is subjected to a composite treatment of sodium alginate, alkali sulfate lignin, ammonium polyphosphate, graphene oxide, magnesium hydroxide, low-temperature plasma, aluminum foil, and carbon fiber impregnation adhesive, and is externally coated with ceramic fibers. The ultra-high molecular weight polyethylene fibers can maintain performance stability in a high-temperature environment, effectively prevent the fibers from melting or thawing, do not melt when exposed to fire, produce low or no smoke, and do not release toxic gases, thereby improving safety in use.

Description

Technical Field

[0001] The invention relates to a preparation method of a high-temperature resistant composite yarn, in particular to a high-temperature resistant flame-retardant ultra-high molecular weight polyethylene composite yarn and a preparation method thereof. Background Art

[0002] Ultra-high molecular weight polyethylene (UHMW-PE) is made from polyethylene resin with a molecular weight of over one million. UHMW-PE fibers offer excellent properties, including high strength and modulus, low elongation at break, strong impact resistance, and chemical resistance. However, this fiber material has significant drawbacks. Its limiting oxygen index (LOI) is only 17%, and its melting point is only around 130°C. It also has a low flame retardancy rating, and its performance degrades dramatically in high-temperature environments.

[0003] In the prior art, Wu Jinshan et al. mixed ultra-high molecular weight polyethylene powder, composite flame retardant additives, and modifiers (the composite flame retardant additives are divided into flame retardants and nano-additives according to their functions) to obtain an organic solution mixture, which was then condensed and spun through twin-screw extrusion to produce flame-retardant ultra-high molecular weight polyethylene fibers. Furthermore, Yang Heng et al. used an ultra-high molecular weight polyethylene solution and a graphene aqueous dispersion (the weight ratio of the ultra-high molecular weight polyethylene solution to the graphene aqueous dispersion was 50-55:1) to form a spinning fluid, which was then extruded to produce frozen collagen filaments. This was then extracted and stretched to produce high-temperature-resistant ultra-high molecular weight polyethylene fibers. Furthermore, Wang Xinrui et al. modified ultra-high molecular weight polyethylene fibers using microencapsulated red phosphorus and carbon black as modifiers. However, using flame retardants to "adhere" to the fiber surface will result in problems such as poor wash resistance and short-term flame retardant effect; using the blending method will encounter the difficulties of UHMWPE's high melt viscosity, the easy entanglement of large molecules in the gel spinning solution, and the difficulty in uniformly dispersing the flame retardant and solvent; the grafting method can solve the problem of poor durability of the post-finishing process, but its effect is not obvious and difficult to achieve.

[0004] In view of this, it is necessary to design a preparation method for improving the high temperature resistance and flame retardant properties of ultra-high molecular weight polyethylene fibers. Summary of the Invention

[0005] In view of the above problems, the present invention aims to provide a method for preparing a high temperature resistant and flame retardant ultra-high molecular weight polyethylene composite yarn, comprising the following steps:

[0006] Step 1: preparing a flame retardant liquid using sodium alginate, alkali sulfate lignin, ammonium polyphosphate, graphene oxide, magnesium hydroxide and deionized water;

[0007] Step 2: immersing the ultra-high molecular weight polyethylene filaments treated with low-temperature plasma in a flame retardant liquid by a dipping and pressing method, taking them out, and then drying them to obtain ultra-high molecular weight polyethylene flame retardant filaments;

[0008] Step 3: After evenly coating the carbon fiber impregnated adhesive on the surface of the ultra-high molecular weight polyethylene flame retardant filament obtained in the previous step, evenly coating the surface of the ultra-high molecular weight polyethylene composite filament with a layer of aluminum foil powder;

[0009] Step 4: After the carbon fiber impregnation adhesive is evenly coated on the surface of the ultra-high molecular weight polyethylene filament treated in the previous step, the carbon fiber is attached and wrapped around the surface of the ultra-high molecular weight polyethylene filament to obtain a composite ultra-high molecular weight polyethylene fiber;

[0010] Step 5: The composite ultra-high molecular weight polyethylene fiber obtained in the previous step is used as the core yarn and the ceramic fiber is used as the wrapping yarn, and the yarn is combined and twisted on a ring spinning machine to obtain a high-temperature resistant and flame-retardant ultra-high molecular weight polyethylene composite yarn.

[0011] Furthermore, the step 1 specifically comprises mixing sodium alginate, alkali sulfate lignin, ammonium polyphosphate, graphene oxide, magnesium hydroxide and deionized water in a mass ratio of 2-5:3-6:3-6:2-4:2-4:5-10 and stirring thoroughly.

[0012] Furthermore, in step 2, the low-temperature plasma treatment power is 1 kW, the treatment time is 10-30 s, and the immersion and pressing are repeated three times to ensure that the flame retardant liquid can fully contact the fiber surface.

[0013] Furthermore, in step 3, the diameter of the aluminum foil powder particles is between 30-70 μm.

[0014] Furthermore, in step 4, after the previous step is completed and the film is left standing at room temperature to ensure that the adhered powder is not easy to fall off, the surface of the ultra-high molecular weight polyethylene filament is coated with carbon fiber impregnation glue. When the carbon fiber is wound, the surface of the ultra-high molecular weight polyethylene filament needs to be wrapped in a circle so that the ultra-high molecular weight polyethylene filament is not exposed.

[0015] A high-temperature resistant and flame-retardant ultra-high molecular weight polyethylene composite yarn is prepared by the above method.

[0016] The beneficial effects of the present invention are:

[0017] The composite yarn adopts a special treatment process. Through the multi-layer composite of composite flame retardant (sodium alginate, alkali sulfate lignin, ammonium polyphosphate, graphene oxide, magnesium hydroxide) and aluminum foil powder, carbon fiber impregnated glue and carbon fiber, the ultra-high molecular weight polyethylene fiber has good high temperature resistance. As a whole, the ultra-high molecular weight polyethylene fiber can maintain performance stability in high temperature environment, effectively prevent the fiber from melting or melting, and improve the safety of use; the composite flame retardant can effectively isolate air convection, multiple and efficient improve the flame retardant properties of the composite yarn, expand the scope of use of ultra-high molecular weight polyethylene fiber, and ensure that the fiber performance maintains excellent, can enhance the mechanical properties of the fiber, improve the tensile strength and wear resistance, and extend the service life.

[0018] In summary, from a practical application perspective, fields such as chemical industry, mining, metallurgy, and power generation often require the use of UHMWPE in high-temperature environments. Poor high-temperature resistance may affect its normal use. The high-temperature resistant and flame-retardant ultra-high molecular weight polyethylene composite yarn prepared above improves the high-temperature resistance and flame retardancy of ultra-high molecular weight polyethylene by optimizing its high-temperature resistance, flame retardancy, and mechanical properties, expanding its application areas and improving fiber properties. DETAILED DESCRIPTION

[0019] The principles and features of the present invention are described below. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0020] Example 1

[0021] 1) The surface of ultra-high molecular weight polyethylene filament with a linear density of 22 tex is plasma treated, wherein the power of the machine equipment is 1 kW and the treatment time is 15 s.

[0022] 2) Prepare a flame retardant solution by mixing sodium alginate, alkali sulfate lignin, ammonium polyphosphate, graphene oxide, magnesium hydroxide, and deionized water in a ratio of 2:3:3:3:2:6. For this, mix 20g of sodium alginate, 30g of alkali sulfate lignin, 30g of ammonium polyphosphate, 30g of graphene oxide, 20g of magnesium hydroxide, and 60ml of deionized water. Stir the mixture for 1 hour to prepare the flame retardant solution.

[0023] 3) Place the prepared ultra-high molecular weight polyethylene filament in the flame retardant liquid and soak it for 30 minutes. Then take out the yarn and apply a 1 kg weight on the yarn for 5 minutes. Repeat this immersion and pressing action three times.

[0024] 4) The ultra-high molecular weight polyethylene filaments after the impregnation treatment were placed in an oven at a temperature of 40° C. and dried for 30 minutes.

[0025] 5) Grind the aluminum foil in a grinder to a fine powder with a powder diameter ranging from 30 to 70 μm;

[0026] 6) Mix the A and B components of the carbon fiber impregnation glue in a ratio of 2:1, where component A is a viscous liquid and component B is also a viscous liquid. Stir and mix them evenly, then apply them to the surface of the filament and coat it with aluminum platinum powder. After adhesion, shake the filament to ensure that the powder does not fall off. If any powder falls off, replenish the missing part.

[0027] 7) The treated ultra-high molecular weight polyethylene filament is allowed to stand at room temperature to ensure that the adhering powder is not easy to fall off, and then the carbon fiber impregnation glue configured above is applied again, and then the carbon fiber is wound in an S-shaped manner, and the surface of the filament needs to be wrapped in a circle without exposing the inside.

[0028] 8) The filament prepared above was used as the core yarn and the ceramic fiber was used as the wrapping yarn. The ring spinning machine was set to have a front roller speed of 15 m / min, a middle roller linear speed of 0.230 m / min, a rear roller linear speed of 0.188 m / min, and a spindle speed of 6200 r / min.

[0029] 9) The yarn prepared above is a high temperature resistant and flame retardant ultra-high molecular weight polyethylene composite yarn.

[0030] Example 2

[0031] Based on Example 1, a flame retardant liquid was prepared by mixing sodium alginate, alkali sulfate lignin, ammonium polyphosphate, graphene oxide, magnesium hydroxide, and deionized water in a ratio of 2:4:4:3:2:7. Specifically, 20g of sodium alginate, 40g of alkali sulfate lignin, 40g of ammonium polyphosphate, 30g of graphene oxide, 20g of magnesium hydroxide, and 70ml of deionized water were mixed and stirred with electromagnetic stirring for 1 hour to prepare the flame retardant liquid. The ring spinning machine was set at a front roller speed of 20m / min, a middle roller linear speed of 0.5m / min, a rear roller linear speed of 0.3m / min, and a spindle speed of 6600r / min.

[0032] Example 3

[0033] Based on Example 1, the surface of the ultra-high molecular weight polyethylene filament was plasma treated for 30 seconds; the carbon fiber was attached in a vertical manner to wrap the surface of the filament without exposing the inside.

[0034] Comparative Example

[0035] The flame retardant liquid formula was changed to 20 g of magnesium hydroxide, 10 g of aluminum hydroxide, mixed with 50 ml of deionized water, and electromagnetically stirred for 1 hour to prepare the flame retardant liquid.

[0036] The prepared ultra-high molecular weight polyethylene filament was placed in the flame retardant liquid and soaked for 30 minutes. Then the yarn was taken out and a 1 kg weight was placed on the yarn to press for 5 minutes. The soaking and pressing action was repeated three times.

[0037] The ultra-high molecular weight polyethylene filaments after the dipping and pressing treatment were placed in an oven at a temperature of 40° C. and dried for 30 minutes.

[0038] The final products of Examples 1, 2, and 3, based on the multi-step composite process of ultra-high molecular weight polyethylene filaments, exhibit significantly improved flame retardancy and high-temperature resistance compared to similar products on the market, with enhanced overall mechanical properties. The selected reagents are environmentally friendly and impart flame retardancy and smoke suppression to the composite yarn, allowing it to withstand temperatures well above 170°C while maintaining excellent mechanical properties. Testing of the product in Example 1 revealed no significant surface changes after 30 minutes of air combustion. Furthermore, hot pressing at 170°C for 10 seconds revealed no significant surface changes, maintaining stable mechanical properties. The decrease in breaking strength and elongation at break was virtually unchanged at 0.2%, effectively extending the product's operational stability under high-temperature fire conditions. In Example 2, increasing the flame retardant solution concentration also achieved flame retardancy for over 30 minutes, maintaining stable mechanical properties. Furthermore, increasing the low-temperature plasma surface treatment time in Example 3 further facilitated the bonding of the flame retardant, aluminum foil powder, and other materials, resulting in excellent coating performance. By comparing Implementation Case 1 with the Control Case, the Control Case will melt during combustion and has a long afterburning time, while Implementation Case 1 is multi-layered with carbon fiber, flame retardant liquid, and aluminum foil powder, and has better high temperature resistance and flame retardant performance, and improves and stably maintains the mechanical properties of the fiber.

[0039] The above is an example of the best mode of implementation of the present invention. Any part not described in detail is common knowledge of a person skilled in the art. The scope of protection of the present invention is based on the content of the claims. Any equivalent transformation based on the technical teachings of the present invention is also within the scope of protection of the present invention.

Claims

1. A method for preparing a high temperature resistant and flame retardant ultra-high molecular weight polyethylene composite yarn, characterized in that: The following steps are involved: Step 1: preparing a flame retardant liquid using sodium alginate, alkali sulfate lignin, ammonium polyphosphate, graphene oxide, magnesium hydroxide and deionized water; Step 2: immersing the ultra-high molecular weight polyethylene filaments treated with low-temperature plasma in a flame retardant liquid by a dipping and pressing method, taking them out, and then drying them to obtain ultra-high molecular weight polyethylene flame retardant filaments; Step 3: After evenly coating the carbon fiber impregnated adhesive on the surface of the ultra-high molecular weight polyethylene flame retardant filament obtained in the previous step, evenly coating the surface of the ultra-high molecular weight polyethylene composite filament with a layer of aluminum foil powder; Step 4: After the carbon fiber impregnation adhesive is evenly coated on the surface of the ultra-high molecular weight polyethylene filament treated in the previous step, the carbon fiber is attached and wrapped around the surface of the ultra-high molecular weight polyethylene filament to obtain a composite ultra-high molecular weight polyethylene fiber; Step 5: The composite ultra-high molecular weight polyethylene fiber obtained in the previous step is used as the core yarn and the ceramic fiber is used as the wrapping yarn, and the yarn is combined and twisted on a ring spinning machine to obtain a high-temperature resistant and flame-retardant ultra-high molecular weight polyethylene composite yarn.

2. The method for preparing the high temperature resistant and flame retardant ultra-high molecular weight polyethylene composite yarn according to claim 1, characterized in that: Specifically, step 1 comprises mixing sodium alginate, alkali sulfate lignin, ammonium polyphosphate, graphene oxide, magnesium hydroxide and deionized water in a mass ratio of 2-5:3-6:3-6:2-4:2-4:5-10 and stirring the mixture thoroughly.

3. The method for preparing the high temperature resistant and flame retardant ultra-high molecular weight polyethylene composite yarn according to claim 1, characterized in that: In step 2, the low-temperature plasma treatment power is 1 kW, the treatment time is 10-30 s, and the immersion pressure is repeated three times to ensure that the flame retardant liquid can fully contact the fiber surface.

4. The method for preparing the high temperature resistant and flame retardant ultra-high molecular weight polyethylene composite yarn according to claim 1, characterized in that: In step 3, the diameter of the aluminum foil powder particles is between 30-70 μm.

5. The method for preparing the high temperature resistant and flame retardant ultra-high molecular weight polyethylene composite yarn according to claim 1, characterized in that: In step 4, after the previous step is completed and the powder is allowed to stand at room temperature to ensure that the adhered powder is not easy to fall off, the surface of the ultra-high molecular weight polyethylene filament is coated with carbon fiber impregnation glue. When the carbon fiber is wound, the surface of the ultra-high molecular weight polyethylene filament needs to be wrapped in a circle so that the ultra-high molecular weight polyethylene filament is not exposed.

6. A high temperature resistant and flame retardant ultra-high molecular weight polyethylene composite yarn, characterized in that: Prepared by the method according to any one of claims 1 to 5.