Preparation method of wear-resistant, mildew-proof and flame-retardant aviation binding rope

Abstract

The invention relates to a preparation method of a wear-resistant, mildew-proof and flame-retardant aviation binding rope, which comprises the following steps: carrying out surface pretreatment on meta-position aramid fiber / flame-retardant chinlon mixed yarns by using ammonia water or a NaOH dilute solution so that the surfaces of the meta-position aramid fiber / flame-retardant chinlon mixed yarns contain a proper amount of carboxyl units, and then treating the meta-position aramid fiber / flame-retardant chinlon mixed yarns by using a thionyl chloride solution so that acyl chloride groups are formed on the surfaces of the yarns; enabling the pretreated mixed yarn to pass through an aminated hyperbranched polysiloxane (NH2-HBPSi) solution, and uniformly grafting a hyperbranched polysiloxane ultrathin film on the surface of the yarn through rapid reaction of amino groups and acyl chloride units; the modified yarn is used as a base material, the warp and the weft are woven into a flat strip in a crossed mode, and the weaving density is larger than or equal to 90%. According to the method, a hyperbranched polysiloxane ultrathin film is constructed on the surface of the aramid fiber mixed yarn through chemical bonds, so that the flexibility and the weaving property of the yarn are not influenced by an ultrathin structure of polysiloxane on the surface; the construction of the hyperbranched polysiloxane ultrathin film can effectively improve the wear resistance of the binding rope.

Description

Technical Field

[0001] The invention belongs to the technical field of high-performance fiber fabric preparation, and in particular relates to a method for preparing a lashing rope that can meet aviation applications. Background Art

[0002] Aramid lashing ropes have the typical advantages of high temperature resistance, fire retardancy, light weight, good dimensional stability, excellent chemical corrosion resistance, and good mechanical properties. Therefore, they are widely used in cable bundling materials such as aircraft and ships. However, aircraft and ships need to experience long-term low-frequency vibrations during service, which puts forward strict requirements on the wear resistance of lashing ropes. The traditional method to improve the wear resistance of lashing ropes is mainly to load fluororubber, microcrystalline wax, calcium carbonate and other materials on the surface of lashing ropes by dipping or coating after preparing the lashing ropes, and improve the lubrication effect on the surface of the lashing ropes. For example, the public patent (CN 201911288327.2) reports a method for improving the wear resistance of aramid lashing ropes by coating lubricating materials on the surface of aramid lashing ropes. However, in the above method, the lashing rope and the lubricating layer are mainly physical. The lubricating layer will still fall off during long-term friction, resulting in problems such as damage to the wear resistance of the lashing ropes.

[0003] In addition, for aramid lashing ropes, the fiber surface is rich in a large number of highly polar amide units, which are easy to combine with water molecules in a humid environment to form hydrogen bonds, and have a high water absorption rate, so they are prone to mold and other problems, which seriously threaten the safety of the lashing ropes. Therefore, how to achieve a synergistic improvement in the wear resistance and mildew resistance of aramid-based lashing ropes through effective structural design and construction is a difficult problem that needs to be solved urgently in this field. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method for preparing a wear-resistant, mildew-proof and flame-retardant aviation lashing rope, so as to overcome the difficulties in the prior art such as the weak bonding between the physical coating or impregnation method lubricating layer and the lashing rope interface, and the difficulty in taking into account both wear resistance and mildew resistance.

[0005] The invention provides a method for preparing a wear-resistant, mildew-proof and flame-retardant aviation lashing rope, the basic process of which includes: immersing meta-aramid / flame-retardant nylon blended yarn in ammonia water or NaOH dilute solution for a period of time, and then transferring the blended yarn to a thionyl chloride solution; continuously passing the pretreated blended yarn through an amination hyperbranched polysiloxane (NH2-HBPSi) / N,N-dimethylformamide (DMF) solution to rapidly react the acyl chloride groups on its surface with the amino groups on the surface of NH2-HBPSi, and then washing and drying to form a uniform HBPSi ultra-thin layer on the yarn surface. The modified yarn is used as the basic material, and the warp and weft yarns are cross-woven into a flat strip.

[0006] The count of the meta-aramid / flame-retardant nylon blended yarn is 10s-30s; the concentration of the ammonia water is 20%-25%, the concentration of the NaOH dilute solution is 0.5-0.8 mol / L, and the treatment time is 5-30 minutes;

[0007] The reaction solvent of the blended yarn in the thionyl chloride solution is one of N,N-dimethylformamide (DMF) or N,N-dimethylacetamide (DMAc), wherein the concentration of thionyl chloride is 10wt%-15wt%, and the reaction is carried out at room temperature for 5-10min;

[0008] The concentration of the NH2-HBPSi / DMF reaction solution is 1wt%-3wt%, and it reacts with the pretreated blended yarn at room temperature for 2-5min to form a hyperbranched polysiloxane ultra-thin film on the yarn surface;

[0009] The thickness of the HBPSi ultra-thin layer is controlled to be 3-10 μm;

[0010] The preparation of the binding rope mainly uses the modified yarn as the basic raw material, and cross-weaves the warp yarn and the weft yarn into a flat strip with a weaving density of ≥90% and a width of 0.5-0.9 cm.

[0011] Beneficial Effects

[0012] The present invention constructs highly active acyl chloride units on the surface of aramid-based blended yarns, and forms an ultra-thin layer of hyperbranched polysiloxane with low surface energy on the yarn surface through the nucleophilic reaction of acyl chlorides and amino groups through chemical bonding, thereby solving the problem of low bonding strength of the wear-resistant layer prepared by the traditional physical method, that is, the ultra-thin structure of the surface polysiloxane does not affect the flexibility and braiding of the yarn, and the construction of the ultra-thin film of hyperbranched polysiloxane can effectively improve the wear resistance of the lashing rope; in addition, the hydrophobic effect of the ultra-thin layer of hyperbranched polysiloxane can effectively reduce the water absorption rate of the aramid-based lashing rope, play a protective role, and improve the mildew resistance of the lashing rope; at the same time, the synergistic effect of the three components of aramid fiber, flame-retardant nylon and hyperbranched polysiloxane in high-temperature fire scenes can give the lashing rope more outstanding flame-retardant properties, without the need for flame-retardant post-finishing or modification, thereby meeting the application requirements in the aviation field. DETAILED DESCRIPTION

[0013] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0014] Sources of materials, sample processing and testing conditions in the embodiments of the present invention:

[0015] Meta-aramid was purchased from Dongguan Tekailun New Material Application Co., Ltd. with a specification of 200D;

[0016] The flame-retardant nylon fiber was purchased from Nantong Kejia Textile Fiber Products Co., Ltd. with a specification of 200D;

[0017] Preparation of meta-aramid / flame-retardant nylon blended yarn: The corresponding raw sliver is obtained after cotton opening and cleaning and carding. Then, the two raw slivers are fully mixed in the drawing process and then prepared through roving, spinning and winding processes, wherein the mixing mass ratio is 80 / 20.

[0018] Abrasion resistance test of lashing rope: According to the national standard GB / T 21196.2-2007 Martindale method for textiles - Determination of abrasion resistance of fabrics - Part 2 - Determination of sample damage, the friction times is 2000 times;

[0019] Anti-mildew performance of lashing rope: tested according to the national standard GB / T 24346-2009 Evaluation of anti-mildew performance of textiles;

[0020] Flame retardant properties of lashing ropes: tested in accordance with national standard GB / T 5454-1997 Textile combustion performance test oxygen index method.

[0021] Example 1

[0022] The meta-aramid / flame-retardant nylon blended yarn with a count of 10s was immersed in a 20% ammonia solution at room temperature for 15 minutes, and then the blended yarn was transferred to a 10wt% thionyl chloride / DMF solution; the pretreated blended yarn was continuously passed through a 1wt% NH2-HBPSi / DMF solution, the yarn movement rate was controlled, the immersion time was ensured to be about 3 minutes, and the thickness of the surface HBPSi film was controlled to be 3.5μm; then the yarn was washed with deionized water to remove the residual thionyl chloride, DMF and other components on the surface, and finally dried at 60°C for 10 minutes to prepare HBPSi modified aramid blended yarn. Using the above modified yarn as the basic material, the warp and weft yarns were cross-woven into flat strips, and the weaving density was controlled to be 90% and the width was 0.3cm.

[0023] Example 2

[0024] The meta-aramid / flame-retardant nylon blended yarn with a count of 10s was immersed in a 0.5% NaOH solution at room temperature and kept for 10 minutes, and then the blended yarn was transferred to a 12wt% thionyl chloride / DMF solution; the pretreated blended yarn was continuously passed through a 3wt% NH2-HBPSi / DMF solution, the yarn movement rate was controlled, the immersion time was ensured to be about 4 minutes, and the thickness of the surface HBPSi film was controlled to be 4μm; then the yarn was washed with deionized water to remove the residual thionyl chloride, DMF and other components on the surface, and finally dried at 60°C for 10 minutes to prepare HBPSi modified aramid blended yarn. Using the above modified yarn as the basic material, the warp and weft yarns were cross-woven into flat strips, and the weaving density was controlled to be 90% and the width was 0.3cm.

[0025] Example 3

[0026] The meta-aramid / flame-retardant nylon blended yarn with a count of 10s was immersed in a 0.5% NaOH solution at room temperature and kept for 10 minutes, and then the blended yarn was transferred to a 15wt% thionyl chloride / DMF solution; the pretreated blended yarn was continuously passed through a 3wt% NH2-HBPSi / DMF solution, the yarn movement rate was controlled, the immersion time was ensured to be about 5 minutes, and the thickness of the surface HBPSi film was controlled to be 8μm; then the yarn was washed with deionized water to remove the residual thionyl chloride, DMF and other components on the surface, and finally dried at 60°C for 10 minutes to prepare HBPSi modified aramid blended yarn. Using the above modified yarn as the basic material, the warp and weft yarns were cross-woven into flat strips, and the weaving density was controlled to be 90% and the width was 0.5cm.

[0027] Example 4

[0028] The meta-aramid / flame-retardant nylon blended yarn with a count of 20s was immersed in a 0.8% NaOH solution at room temperature for 20 minutes, and then the blended yarn was transferred to a 15wt% thionyl chloride / DMF solution; the pretreated blended yarn was continuously passed through a 3wt% NH2-HBPSi / DMAc solution, the yarn movement rate was controlled, the immersion time was ensured to be about 5 minutes, and the thickness of the surface HBPSi film was controlled to be 10μm; then the yarn was washed with deionized water to remove the residual thionyl chloride, DMF, DMAc and other components on the surface, and finally dried at 60°C for 10 minutes to prepare HBPSi modified aramid blended yarn. Using the above modified yarn as the base material, the warp and weft yarns were cross-woven into flat strips, and the weaving density was controlled to be 90% and the width was 0.5cm.

[0029] Comparative Example 1

[0030] The meta-aramid / flame-retardant nylon blended yarn with a count of 20s was continuously passed through a 3wt% NH2-HBPSi / DMAc solution, the yarn movement rate was controlled, the immersion time was ensured to be about 5min, and the thickness of the HBPSi film coated on the surface was controlled to be 10μm; then the yarn was washed with deionized water to remove the residual DMAc and other components on the surface, and finally it was dried at 60℃ for 10min to prepare the NH2-HBPSi physically coated aramid blended yarn. Using the above modified yarn as the basic material, the warp and weft yarns were cross-woven into flat strips, and the weaving density was controlled to be 90% and the width was 0.5cm.

[0031] Comparative Example 2

[0032] The meta-aramid / flame-retardant nylon blended yarn with a count of 20s was immersed in a coating solution consisting of 30 parts of fluororubber, 30 parts of microcrystalline wax and 40 parts of calcium carbonate for 30 minutes; after coating, the yarn was washed with deionized water to remove the residual components on the surface, and finally dried at 60°C for 10 minutes to prepare a physically coated aramid blended yarn. Using the above modified yarn as the base material, the warp yarn and the weft yarn were cross-woven into a flat strip, and the weaving density was controlled to be 90% and the width was 0.5cm;

[0033] Table 1 Abrasion resistance, mildew resistance and flame retardancy of the lashing rope prepared by the present invention.

[0034]

[0035] From the comparison results of Comparative Example 1 and Example 4, it can be seen that since the surface activation treatment of the yarn was not performed using a dilute NaOH solution and a thionyl chloride solution in Comparative Example 1, no highly active acyl chloride groups or the like were formed on the yarn surface, and thus it could not undergo a cross-linking reaction with NH2-HBPSi to form a chemical bond. NH2-HBPSi was only physically bonded to the yarn surface, and the interfacial effect was not strong. Therefore, the wear resistance of the yarn was poor, and the mildew resistance level was weaker than that of Example 4.

[0036] From the comparison results of Comparative Example 2 and Example 4, it can be seen that by using traditional fluororubber, microcrystalline wax and calcium carbonate as mildew-proof and wear-resistant coatings, through simple physical coating, the wear resistance and mildew-proof level of the yarn are weaker than the implementation effect of the present invention.

Claims

1. A method for preparing a wear-resistant, mildew-proof and flame-retardant aviation lashing rope, characterized in that: The meta-aramid / flame-retardant nylon blended yarn is immersed in ammonia or NaOH dilute solution for a period of time, and then the blended yarn is transferred to a dichlorothionyl solution; the pretreated blended yarn is continuously passed through an amino hyperbranched polysiloxane (NH2-HBPSi) / N,N-dimethylformamide (DMF) solution to allow the surface acyl chloride groups to react quickly with the amino groups on the surface of NH2-HBPSi, and then washed and dried to form a uniform HBPSi ultra-thin layer on the yarn surface. The modified yarn is used as the base material, and the warp and weft yarns are cross-woven into flat strips.

2. The method for preparing the wear-resistant, mildew-proof and flame-retardant aviation lashing rope according to claim 1, characterized in that: The count of meta-aramid / flame retardant nylon blended yarn is 10s-30s.

3. The method for preparing the wear-resistant, mildew-proof and flame-retardant aviation lashing rope according to claim 1, characterized in that: The concentration of ammonia water is 20%-25%, the concentration of NaOH dilute solution is 0.5-0.8 mol / L, and the treatment time is 5-30 min.

4. The method for preparing the wear-resistant, mildew-proof and flame-retardant aviation lashing rope according to claim 1, characterized in that: The reaction solvent of the blended yarn in the thionyl chloride solution is one of N,N-dimethylformamide (DMF) and N,N-dimethylacetamide (DMAc), the concentration of the thionyl chloride is 10wt%-15wt%, and the reaction is carried out at room temperature for 5-10 minutes.

5. The method for preparing the wear-resistant, mildew-proof and flame-retardant aviation lashing rope according to claim 1, characterized in that: The concentration of the NH2-HBPSi / DMF reaction solution is 1wt%-3wt%, and the NH2-HBPSi / DMF reaction solution reacts with the pretreated blended yarn at room temperature for 2-5 minutes to form a hyperbranched polysiloxane ultra-thin film on the surface of the yarn.

6. The method for preparing the wear-resistant, mildew-proof and flame-retardant aviation lashing rope according to claim 1, characterized in that: The thickness of the HBPSi ultra-thin layer is controlled to be 3-10 μm.

7. The method for preparing the wear-resistant, mildew-proof and flame-retardant aviation lashing rope according to claim 1, characterized in that: The modified yarn is used as the basic raw material, and the warp yarn and the weft yarn are cross-woven into a flat strip, the weaving density is ≥90%, and the width is 0.5-0.9 cm.

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