A high temperature resistant ultra-high molecular weight polyethylene fiber-alumina fiber composite yarn and its preparation method

Abstract

The present invention relates to a high-temperature resistant ultra-high molecular weight polyethylene fiber-alumina fiber composite yarn and a preparation method thereof. The method of the present invention comprises the following steps: 1. rolling an aluminum foil material into a fine granular shape; adding nano-carbon powder and fine aluminum foil particles to a polyimide epoxy resin to obtain a mixed adhesive; 2. immersing the ultra-high molecular weight polyethylene fiber after corona discharge treatment in the mixed adhesive prepared in step 1 and taking it out, placing it in an oven for drying, and then leaving it at room temperature for more than 1 hour to obtain a composite ultra-high molecular weight polyethylene fiber; 3. Using the composite ultra-high molecular weight polyethylene fiber as the core yarn and the alumina fiber as the outer yarn, a high-temperature resistant ultra-high molecular weight polyethylene fiber-alumina fiber composite yarn is prepared by a friction spinning machine. The composite yarn of the present invention has excellent high temperature resistance and fire resistance, can be used normally under an environment above 400°C, improves the use temperature conditions of the ultra-high molecular weight polyethylene fiber, and can be more widely used.

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 ultra-high molecular weight polyethylene fiber-alumina fiber composite yarn and a preparation method thereof. Background Art

[0002] Ultra-high molecular weight polyethylene (UHMWPE) refers to unbranched linear polyethylene with a viscosity-average molecular weight greater than 1.5 million. UHMWPE fiber is made from UHMWPE. Its ultra-high molecular weight gives UHMWPE fibers excellent properties, including strong wear resistance, good lubricity, high strength, chemical stability, and aging resistance. Therefore, UHMWPE fibers are widely used in defense and military equipment (e.g., bulletproof vests, armor plates for helicopters, tanks, and ships), aerospace (e.g., wingtip structures for various aircraft, parachutes used for landing, ropes used to suspend heavy objects from aircraft), and civilian applications (e.g., impact-resistant, rust-resistant, and corrosion-resistant coating materials used on the exterior surfaces of ships in marine engineering, anti-corrosion, anti-adhesion, and wear-resistant materials for various marine structural components, pressure vessels used in industry, conveyor belts, filter materials, and dental tray materials used in the medical field).

[0003] However, the melting point of polyethylene material is relatively low, only around 130°C, and the thermal aging rate of ultra-high molecular weight polyethylene fiber under stretching conditions is relatively fast. Therefore, its maximum operating temperature is generally between 80-100°C, which limits its application in high-temperature environments. Summary of the Invention

[0004] In view of the above problems, the present invention aims to provide a method for preparing a high-temperature resistant ultra-high molecular weight polyethylene fiber-alumina fiber composite yarn, comprising the following steps:

[0005] Step 1: rolling the aluminum foil material into fine particles; adding nano-carbon powder and fine aluminum foil particles to polyimide epoxy resin to obtain a mixed adhesive;

[0006] Step 2: Immerse the ultra-high molecular weight polyethylene fiber after corona discharge treatment in the mixed adhesive prepared in step 1, take it out, place it in an oven for drying, and then place it at room temperature for more than 1 hour to obtain a composite ultra-high molecular weight polyethylene fiber;

[0007] Step 3: The composite ultra-high molecular weight polyethylene fiber obtained after the treatment in step 2 is used as the core yarn and the alumina fiber is used as the outer yarn, and a high-temperature resistant ultra-high molecular weight polyethylene fiber-alumina fiber composite yarn is prepared by a friction spinning machine.

[0008] Furthermore, in step 1, the aluminum foil material is rolled into particles with a diameter between 0.1 and 1 mm.

[0009] Furthermore, the step 1 is specifically as follows: polyimide epoxy resin, aluminum foil particles and nano-carbon powder are mixed in a mass ratio of 2:1:1, and stirred thoroughly with a magnetic stirrer so that the aluminum foil particles and nano-carbon powder are evenly distributed in the adhesive to obtain a mixed adhesive.

[0010] Furthermore, the corona discharge treatment method in step 2 is specifically as follows: washing with deionized water several times until the pH value is measured as neutral using pH paper, drying the washed ultra-high molecular weight polyethylene fiber in a drying oven at 40-60° C. to remove moisture, and then corona treating the fiber at a speed of 3-10 m / s and a voltage of 10-20 kV.

[0011] Furthermore, the step 2 specifically includes completely immersing the corona-treated ultra-high molecular weight polyethylene fiber in the mixed adhesive, taking it out, drying it in an oven at 60-80° C. for 30-50 minutes, and then placing it at room temperature for more than 1 hour.

[0012] Furthermore, the ultra-high molecular weight polyethylene fiber is a small-sized rolled yarn obtained by winding a large tube of ultra-high molecular weight polyethylene fiber.

[0013] Furthermore, the linear density of the ultra-high molecular weight polyethylene fiber in step 1 is 10-200 tex, and the linear density of the alumina fiber is 30-160 tex.

[0014] A high-temperature resistant ultra-high molecular weight polyethylene fiber-alumina fiber composite yarn is prepared by the above method.

[0015] The beneficial effects of the present invention are as follows: a high-temperature resistant ultra-high molecular weight polyethylene composite yarn prepared by the method has the following advantages: (1) the ultra-high molecular weight polyethylene fiber can be subjected to corona treatment to improve the interfacial bonding strength of the fiber surface by more than 300%, the shear strength is improved by more than about 30%, and the surface roughness is improved, and active polar groups are introduced at the same time; (2) the polyimide epoxy resin can withstand high temperatures of up to 400°C, and can be mixed with aluminum foil particles and nano-carbon powder to further enhance the high-temperature resistance, fill the gaps, and protect the ultra-high molecular weight polyethylene fiber from the outside world. Moreover, the particles can increase friction, which is beneficial for the subsequent coating of alumina fibers; (3) Alumina fibers can withstand temperatures of 1400-1800°C. They combine the characteristics of crystal materials and fiber materials, and have excellent properties such as good thermal stability, high mechanical strength, large elastic modulus, low thermal conductivity, strong insulation, and strong resistance to chemical corrosion. Coating them on the outside of ultra-high molecular weight polyethylene fibers can achieve effective high-temperature protection and isolate heat transfer from the outside air; (4) Alumina fibers have excellent fire resistance and are not easy to burn, which can enhance the fire resistance of composite fibers; (5) The double layer effectively protects ultra-high molecular weight polyethylene fibers, and the layered protection isolates heat.

[0016] Therefore, the present invention provides a method for preparing ultra-high molecular weight polyethylene composite yarn, which has excellent high temperature resistance and fire resistance, and can be normally used in an environment with a high temperature resistance of up to 400°C or above, greatly improving the operating temperature conditions of ultra-high molecular weight polyethylene fibers and can be more widely used. DETAILED DESCRIPTION

[0017] 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.

[0018] Example 1

[0019] 1) Ultra-high molecular weight polyethylene filaments with a linear density of 180 tex (960 f), a fiber diameter of 20 μm, and a fiber density of 0.999 g / cm3 were washed several times with deionized water until the pH value was neutral as measured by pH paper. The washed ultra-high molecular weight polyethylene fibers were dried in a drying oven at 40-60°C to remove moisture. The fibers were then corona treated at a speed of 6 m / s and a voltage of 15 kV.

[0020] 2) Grind the aluminum foil into particles with a diameter of 0.1-1mm.

[0021] 3) Prepare polyimide epoxy resin, aluminum foil particles, and nano-carbon powder in a ratio of 2:1:1, that is, prepare 20g of polyimide epoxy resin, 10g of aluminum foil particles, and 10g of nano-carbon powder. Mix the three and put them into a magnetic stirrer for thorough stirring so that the aluminum foil particles and nano-carbon powder are evenly distributed in the adhesive.

[0022] 4) The corona-treated ultra-high molecular weight polyethylene fiber is completely immersed in the mixed adhesive, then taken out and placed in an oven for 30 minutes for drying, and then placed in a dry environment for 1 hour.

[0023] 5) The treated ultra-high molecular weight polyethylene fibers and alumina fibers (76 tex) are coated on a friction spinning machine to obtain high-temperature resistant ultra-high molecular weight polyethylene composite yarn.

[0024] Example 2

[0025] Based on Example 1, the speed during corona discharge treatment was changed to 8 m / s, the voltage was 10 kV, and 40 g of polyimide epoxy resin, 20 g of aluminum foil particles, and 20 g of nano-carbon powder were prepared and mixed.

[0026] Comparative Cases

[0027] The ultra-high molecular weight polyethylene filament was washed several times with deionized water until it was neutral as measured by pH paper. The washed ultra-high molecular weight polyethylene fiber was placed in a drying oven at 40-60°C to remove moisture. The fiber was then corona treated at a speed of 6m / s and a voltage of 15kV.

[0028] The treated ultra-high molecular weight polyethylene fibers and ordinary ultra-high molecular weight polyethylene fibers are coated on a friction spinning machine to obtain ultra-high molecular weight polyethylene composite yarn.

[0029] Examples 1 and 2, compared with the comparative example, demonstrate that the high-temperature resistance of the composite yarn, based on the double-layer insulation of ultra-high molecular weight polyethylene filaments and a high-temperature resistant composite material, is significantly improved. The composite yarn can withstand temperatures exceeding 400°C. Testing of the composite yarn prepared according to Example 1 revealed that after treatment at 220°C for 20 seconds, its mechanical properties remained stable, with a decrease in breaking strength and elongation of 0.1%-0.3%, showing almost no change. The yarn surface also showed no curling or bonding, demonstrating the improved high-temperature performance of the composite yarn. Increasing the temperature to 400°C also showed no significant changes in the fiber surface, with a decrease in breaking strength and elongation of 0.8%-1.4%. In Example 2, by varying the corona treatment time and voltage, the adhesion between the polyimide-epoxy resin, aluminum foil, and nano-carbon powder composite and ultra-high molecular weight polyethylene fibers was weaker than in Example 1. Comparing Example 1 with the comparative example, the comparative example exhibited a decline in mechanical properties at 140°C, exhibiting stress cracking and degradation, surface melting, and inter-fiber bonding. By comparison, the high temperature resistance of the composite yarn in Example 1 is greatly improved, and the mechanical properties remain stable.

[0030] The foregoing is an example of the best mode of carrying out the present invention. Any portion not described in detail herein is common knowledge within the skill of one of ordinary skill in the art. The scope of protection of the present invention is determined by 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 ultra-high molecular weight polyethylene fiber-alumina fiber composite yarn, characterized in that: The following steps are involved: Step 1: rolling the aluminum foil material into fine particles; adding nano-carbon powder and fine aluminum foil particles to polyimide epoxy resin to obtain a mixed adhesive; Step 2: Immerse the ultra-high molecular weight polyethylene fiber after corona discharge treatment in the mixed adhesive prepared in step 1, take it out, place it in an oven for drying, and then place it at room temperature for more than 1 hour to obtain a composite ultra-high molecular weight polyethylene fiber; Step 3: The composite ultra-high molecular weight polyethylene fiber obtained after the treatment in step 2 is used as the core yarn and the alumina fiber is used as the outer yarn, and a high-temperature resistant ultra-high molecular weight polyethylene fiber-alumina fiber composite yarn is prepared by a friction spinning machine.

2. The method for preparing the high temperature resistant ultra-high molecular weight polyethylene fiber-alumina fiber composite yarn according to claim 1, characterized in that: In the step 1, the aluminum foil material is rolled into particles with a diameter between 0.1 and 1 mm.

3. The method for preparing the high temperature resistant ultra-high molecular weight polyethylene fiber-alumina fiber composite yarn according to claim 1, characterized in that: Specifically, step 1 comprises mixing polyimide epoxy resin, aluminum foil particles and nano-carbon powder in a mass ratio of 2:1:1, and stirring them fully with a magnetic stirrer so that the aluminum foil particles and nano-carbon powder are evenly distributed in the adhesive to obtain a mixed adhesive.

4. The method for preparing the high temperature resistant ultra-high molecular weight polyethylene fiber-alumina fiber composite yarn according to claim 1, characterized in that: The corona discharge treatment method in step 2 is specifically as follows: washing the ultra-high molecular weight polyethylene fiber with deionized water several times until it is neutral when measured by pH test paper, drying the washed ultra-high molecular weight polyethylene fiber in a drying oven at 40-60° C. to remove moisture, and then corona treating the fiber at a speed of 3-10 m / s and a voltage of 10-20 kV.

5. The method for preparing the high temperature resistant ultra-high molecular weight polyethylene fiber-alumina fiber composite yarn according to claim 1, characterized in that: Specifically, the step 2 is to completely immerse the corona-treated ultra-high molecular weight polyethylene fiber in the mixed adhesive, take it out, place it in an oven at 60-80° C. for 30-50 minutes, and then place it at room temperature for more than 1 hour.

6. The method for preparing the high temperature resistant ultra-high molecular weight polyethylene fiber-alumina fiber composite yarn according to claim 1, characterized in that: The ultra-high molecular weight polyethylene fiber is a small-sized rolled yarn obtained by winding a large tube of ultra-high molecular weight polyethylene fiber.

7. The method for preparing the high temperature resistant ultra-high molecular weight polyethylene fiber-alumina fiber composite yarn according to claim 1, characterized in that: The linear density of the ultra-high molecular weight polyethylene fiber in step 1 is 10-200 tex, and the linear density of the alumina fiber is 30-160 tex.

8. A high temperature resistant ultra-high molecular weight polyethylene fiber-alumina fiber composite yarn, characterized in that: Prepared by the method according to any one of claims 1 to 7.