Preparation method of high-elasticity and high-strength spandex fiber fabric

Abstract

The invention relates to the technical field of spandex fibers, and discloses a preparation method of a high-elasticity and high-strength spandex fiber fabric, which comprises the following steps: blending polyurethane with a modified graphene flame retardant, carrying out electrostatic spinning to obtain spandex fibers, and carrying out twisting, warping, weaving and other processes to obtain the high-elasticity and high-strength spandex fiber fabric. The graphene-grafted polymer flame retardant contains a ureido structure, and can form electrostatic interaction with a carbamate structure in polyurethane, so that graphene and spandex fibers form an electrostatic cross-linked network, and the interfacial interaction between graphene and spandex fibers is enhanced, thereby improving the breaking strength and elongation at break of the spandex fibers and enhancing the tensile strength of the spandex fibers. And the fiber has better strength and elasticity.

Description

Technical Field

[0001] The invention relates to the technical field of spandex fibers, in particular to a method for preparing a high-elasticity and high-strength spandex fiber fabric. Background Art

[0002] Spandex fiber has high elasticity and resilience, and is a synthetic fiber with excellent performance. It is widely used in textiles, clothing and accessories. In order to meet the actual application of spandex fiber in functional fibers and fabrics, it is necessary to improve its elasticity, strength and other properties. Graphene, as a carbon nanomaterial, has the advantages of good heat resistance and high strength. It has broad application prospects in flame retardants, refractory materials, thermal insulation materials, etc. The document "Preparation and Performance Research of Biomass Graphene Modified Spandex Fiber" uses dry spinning to prepare biomass graphene modified spandex fiber, which has good far-infrared function and antibacterial properties, and is expected to replace traditional spandex filaments, but it does not solve the problem of flammability and low strength of spandex fiber. The present invention aims to prepare a modified graphene flame retardant to improve the flame retardancy and strength of spandex fiber and fabric. Summary of the invention

[0003] The technical problem solved by the present invention is: a modified graphene flame retardant is prepared to solve the shortcomings of spandex fibers and fabrics, such as poor flame retardancy and poor strength.

[0004] The technical solution provided by the present invention is:

[0005] A method for preparing a high-elasticity and high-strength spandex fiber fabric comprises the following steps: adding polyurethane to N,N-dimethylacetamide, stirring to form a spinning solution, then adding a modified graphene flame retardant, ultrasonically oscillating, and then electrostatically spinning the spinning solution, with a spinning voltage of 16-20 kV, a spinning speed of 1-2.5 mL / h, and a receiving distance of 12-20 cm to obtain spandex fibers; twisting, warping, sizing, and weaving the spandex fibers to obtain a high-elasticity and high-strength spandex fiber fabric.

[0006] Furthermore, the mass fraction of polyurethane in the spinning solution is 12-18%.

[0007] Furthermore, the mass of the modified graphene flame retardant is 1-8% of the mass of the polyurethane.

[0008] Furthermore, the preparation method of the modified graphene flame retardant includes the following steps: adding amino-modified graphene to N,N-dimethylacetamide, ultrasonically shaking, adding diphenylmethane-4,4'-diisocyanate and bisaminobenzimidazole phosphate, stirring and reacting at a temperature of 70-110°C for 6-12h, cooling, filtering, washing with water and ethanol in turn, and drying to obtain the modified graphene flame retardant.

[0009] Furthermore, the mass of the amino-modified graphene of diphenylmethane-4,4'-diisocyanate and bisaminobenzimidazole phosphate is (80-200)% and (180-400)% of the mass of the polyurethane, respectively.

[0010] Further, the preparation method of bisaminobenzimidazole phosphate comprises the following steps:

[0011] S11: Add 2,2-bis(bromomethyl)-1,3-propanediol, structural formula: 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphorinane-2-oxide and triethylamine are reacted at room temperature for 12-24 hours, concentrated, washed with n-hexane, and dried to obtain 2,2-bis(bromomethyl)-1,3-phosphate intermediate. The reaction formula is as follows:

[0012]

[0013] S12: Add 6-nitrobenzimidazole and tetrabutylammonium bromide (TBAB) to a sodium hydroxide solution, add 2,2-bis(bromomethyl)-1,3-phosphate intermediate, stir and react at room temperature for 6-12 hours, add chloroform, stand and separate the liquid, separate the organic layer, concentrate, wash the product with n-hexane and add the product to water, add reduced iron powder and ammonium chloride, react at 70-85°C for 3-8 hours, cool, add ethyl acetate, collect the filtrate after filtering, stand and separate the liquid, separate the organic layer, concentrate, and recrystallize the product with ethanol to obtain bisaminobenzimidazole phosphate. The reaction formula is as follows:

[0014]

[0015] Furthermore, the masses of 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphinane-2-oxide and triethylamine in S11 are (140-190)% and (75-90)% of the mass of 2,2-bis(bromomethyl)-1,3-propanediol, respectively.

[0016] Furthermore, the masses of 6-nitrobenzimidazole and tetrabutylammonium bromide in S12 are (120-180)% and (9-14)% of the mass of the 2,2-bis(bromomethyl)-1,3-phosphate intermediate, respectively.

[0017] The technical effect of the present invention is that: a novel bisaminobenzimidazole phosphate is prepared by using cheap and readily available 2,2-bis(bromomethyl)-1,3-propanediol, 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphorinane-2-oxide, 6-nitrobenzimidazole and the like as reaction raw materials, wherein the bisamino groups contained in the novel bisaminobenzimidazole phosphate can react with diphenylmethane-4,4'-diisocyanate on the surface of amino-modified graphene by in-situ graft polymerization, thereby realizing the grafting of a polymer flame retardant containing a benzimidazole phosphate structure onto the surface of graphene, and obtaining a modified graphene flame retardant.

[0018] The present invention blends the modified graphene flame retardant with polyurethane and electrospins it to obtain spandex fiber, and then obtains high-elasticity and high-strength spandex fiber fabric through twisting, warping, weaving and other processes. The graphene-grafted polymer flame retardant contains a urea-based structure. Can be combined with the urethane structure in polyurethane The electrostatic interaction is formed, so that the graphene and the spandex fiber form an electrostatic cross-linking network, which enhances the interface interaction between the graphene and the spandex fiber, thereby improving the breaking strength and breaking elongation of the spandex fiber, and making the fiber have better strength and elasticity.

[0019] The present invention grafts a polymer flame retardant containing a benzimidazole phosphate structure onto the surface of graphene, and the nitrogen-phosphorus-graphene synergistic flame retardant effect is achieved. When burned, the grafted polymer flame retardant can promote the dehydration of spandex fiber fabric into carbon, and form a continuous and stable carbon layer with graphene, which hinders the conduction of heat into the interior of the fiber fabric and inhibits the conduction of oxygen, thereby achieving an excellent flame retardant effect. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present application are described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0021] Main raw materials: amino-modified graphene: thickness 0.6-1.2nm; flake diameter 0.5-5um, amino content 4wt%; Suzhou Kaifa New Materials.

[0022] Polyurethane: active ingredient content 100%; Dongguan Jiurui plastic raw material.

[0023] 2-Chloro-5,5-dimethyl-1,3,2-dioxaphosphinane-2-oxide; purity 97%; CAS No. 4090-55-5; Anaiji Chemical.

[0024] 6-Nitrobenzimidazole: purity 98%; CAS number 94-52-0; Anaiji Chemical.

[0025] 2,2-Bis(bromomethyl)-1,3-propanediol; CAS No. 3296-90-0; Purity: 98%

[0026] Example 1

[0027] (1) Add 0.2 g of 2,2-bis(bromomethyl)-1,3-propanediol, 0.35 g of 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphorinane-2-oxide and 0.17 g of triethylamine to dichloromethane, react at room temperature for 24 h, concentrate, wash with n-hexane, and dry to obtain a 2,2-bis(bromomethyl)-1,3-phosphate intermediate.

[0028] (2) 0.7 g of 6-nitrobenzimidazole and 0.052 g of tetrabutylammonium bromide were added to a sodium hydroxide solution with a mass fraction of 26%, and 0.5 g of 2,2-bis(bromomethyl)-1,3-phosphate intermediate was added. The mixture was stirred at room temperature for 6 h, and chloroform was added. The mixture was allowed to stand for separation, the organic layer was separated, and the mixture was concentrated. The product was washed with n-hexane and then added to water. Reduced iron powder and ammonium chloride were added, and the mixture was reacted at 85° C. for 6 h. The mixture was cooled, ethyl acetate was added, the filtrate was collected after filtration, the mixture was allowed to stand for separation, the organic layer was separated, and the mixture was concentrated. The product was recrystallized from ethanol to obtain bisaminobenzimidazole phosphate.

[0029] (3) Add 0.1 g of amino-modified graphene to N,N-dimethylacetamide, ultrasonically shake, add 0.08-0.2 g of diphenylmethane-4,4'-diisocyanate and 0.18-0.4 g of bisaminobenzimidazole phosphate, stir and react at 100° C. for 8 h, cool, filter, wash with water and ethanol in turn, and dry to obtain a modified graphene flame retardant.

[0030] (4) Adding polyurethane to N,N-dimethylacetamide, stirring to prepare a spinning solution with a mass fraction of 14%, then adding 1-8% of the mass of the polyurethane modified graphene flame retardant, ultrasonically oscillating, and then electrospinning the spinning solution at a spinning voltage of 18 kV, a spinning speed of 1.5 mL / h, and a receiving distance of 15 cm to obtain spandex fiber; twisting, warping, sizing, and weaving the spandex fiber to obtain a high-elasticity and high-strength spandex fiber fabric.

[0031] Example 2

[0032] The difference from Example 1 is that in step (3), the mass of diphenylmethane-4,4'-diisocyanate is 0.12 g and the mass of bisaminobenzimidazole phosphate is 0.25 g.

[0033] Example 3

[0034] The difference from Example 1 is that in step (3), the mass of diphenylmethane-4,4'-diisocyanate is 0.16 g and the mass of bisaminobenzimidazole phosphate is 0.32 g.

[0035] Example 4

[0036] The difference from Example 1 is that in step (3), the mass of 0.12 g of diphenylmethane-4,4'-diisocyanate is 0.2 g, and the mass of bisaminobenzimidazole phosphate is 0.4 g.

[0037] Example 5

[0038] The difference from Example 1 is that in step (4), the mass of the modified graphene flame retardant is 3% of the mass of the polyurethane.

[0039] Example 6

[0040] The difference from Example 1 is that the mass of the modified graphene flame retardant in step (4) is 5% of the mass of the polyurethane.

[0041] Example 7

[0042] The difference from Example 1 is that in step (4), the mass of the modified graphene flame retardant is 8% of the mass of the polyurethane.

[0043] Comparative Example 1

[0044] The difference from Example 1 is that in step (4), amino-modified graphene is used instead of modified graphene flame retardant.

[0045] Comparative Example 2

[0046] The difference from Example 1 is that amino-modified graphene is not added in step (3);

[0047] 0.08 g of diphenylmethane-4,4'-diisocyanate and 0.18 g of bisaminobenzimidazole phosphate were added to N,N-dimethylacetamide, and the mixture was stirred and reacted at 100°C for 8 h. The mixture was cooled, filtered, washed with water and ethanol in sequence, and dried to obtain a polymer flame retardant.

[0048] The polyurethane is added to N,N-dimethylacetamide and stirred to prepare a spinning solution with a mass fraction of 14%, and then a polymer flame retardant of 1% of the mass of the polyurethane is added, ultrasonically vibrated, and then the spinning solution is electrostatically spun with a spinning voltage of 18 kV, a spinning speed of 1.5 mL / h, and a receiving distance of 15 cm to obtain spandex fiber; the spandex fiber is twisted, warped, sized, and woven to obtain spandex fiber fabric.

[0049] The flame retardant properties of spandex fiber fabrics were tested using an oxygen index tester, and the test results are as follows:

[0050] Limiting oxygen index of spandex fiber fabric (%) Implementation Standards GB / T 5454-1997 Example 1 26.2 Example 2 27.3 Example 3 28.1 Example 4 28.7 Comparative Example 1 24.3 Comparative Example 2 26.0

[0051] In Examples 1-4, as the mass of diphenylmethane-4,4'-diisocyanate and the mass of bisaminobenzimidazole phosphate gradually increase, more and more polymer flame retardants are grafted on the surface of graphene, and the limiting oxygen index becomes larger and larger. The polymer flame retardant and graphene form a synergistic flame retardant effect, which significantly improves the flame retardancy of the spandex fiber fabric.

[0052] In Comparative Example 1, amino-modified graphene is used instead of modified graphene flame retardant, and graphene is not grafted with polymer flame retardant, and the flame retardant effect on spandex fiber is not obvious.

[0053] Comparative Example 2 uses a polymer flame retardant instead of the modified graphene flame retardant, which does not produce a synergistic flame retardant effect with graphene, and its limiting oxygen index is slightly lower than that of Example 1.

[0054] The flame retardant properties of spandex fiber fabrics are tested using an oxygen index tester, and the mechanical properties of spandex fibers are tested using an electronic single fiber strength tester.

[0055] The test results are as follows:

[0056]

[0057] As the amount of modified graphene flame retardant gradually increases, the limiting oxygen index of spandex fiber fabric becomes larger and larger. When its mass is 8% of the mass of polyurethane, the maximum limiting oxygen index of spandex fiber fabric is 29.8%.

[0058] However, as the amount of modified graphene flame retardant gradually increased, the breaking strength of spandex fiber increased and then decreased. When its mass was 3% of the mass of polyurethane, the maximum tear strength was 1.95 cN / dtex. When its mass was 1% of the mass of polyurethane, the maximum elongation at break was 531.0%.

[0059] The above are only typical examples of the present invention. In addition, the present invention may have many other specific implementations. Any technical solutions formed by equivalent replacement or equivalent transformation fall within the scope of protection required by the present invention.

Claims

1. A method for preparing a high-elasticity and high-strength spandex fiber fabric, characterized in that: The following steps are involved: Add polyurethane to N,N-dimethylacetamide and stir to form a spinning solution, then add a modified graphene flame retardant, ultrasonically vibrate, and then electrospin the spinning solution with a spinning voltage of 16-20kV, a spinning speed of 1-2.5mL / h, and a receiving distance of 12-20cm to obtain spandex fiber; twist, warp, size, and weave the spandex fiber to obtain a high-elasticity and high-strength spandex fiber fabric.

2. The method for preparing the high-elasticity and high-strength spandex fiber fabric according to claim 1, characterized in that: The mass fraction of polyurethane in the spinning solution is 12-18%.

3. The method for preparing the high-elasticity and high-strength spandex fiber fabric according to claim 1, characterized in that: The mass of the modified graphene flame retardant is 1-8% of the mass of the polyurethane.

4. The method for preparing the high-elasticity and high-strength spandex fiber fabric according to claim 3, characterized in that: The preparation method of the modified graphene flame retardant comprises the following steps: adding amino-modified graphene to N,N-dimethylacetamide, ultrasonically shaking, adding diphenylmethane-4,4'-diisocyanate and bisaminobenzimidazole phosphate, stirring and reacting at a temperature of 70-110°C for 6-12h, cooling, filtering, washing with water and ethanol in sequence, and drying to obtain the modified graphene flame retardant.

5. The method for preparing the high-elasticity and high-strength spandex fiber fabric according to claim 4, characterized in that: The mass of diphenylmethane-4,4'-diisocyanate and bisaminobenzimidazole phosphate are respectively (80-200)% and (180-400)% of the mass of the amino-modified graphene in the polyurethane.

6. The method for preparing a high-elasticity and high-strength spandex fiber fabric according to claim 5, characterized in that: The preparation method of bisaminobenzimidazole phosphate comprises the following steps: S11: Add 2,2-bis(bromomethyl)-1,3-propanediol, 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphorinane-2-oxide and triethylamine to dichloromethane, react at room temperature for 12-24 hours, concentrate, wash with n-hexane, and dry to obtain a 2,2-bis(bromomethyl)-1,3-phosphate intermediate; S12: 6-nitrobenzimidazole and tetrabutylammonium bromide are added to a sodium hydroxide solution, and 2,2-bis(bromomethyl)-1,3-phosphate intermediate is added, and the reaction is stirred at room temperature for 6-12 hours, and chloroform is added, and the liquid is separated and the organic layer is separated, and the product is concentrated. After the product is washed with n-hexane, the product is added to water, and reduced iron powder and ammonium chloride are added. The reaction is carried out at a temperature of 70-85°C for 3-8 hours, and the solution is cooled, and ethyl acetate is added. The filtrate is collected after filtering, and the liquid is separated and the organic layer is separated and concentrated. The product is recrystallized from ethanol to obtain bisaminobenzimidazole phosphate, the structural formula of which is 7. The method for preparing a high-elasticity and high-strength spandex fiber fabric according to claim 6, characterized in that: The masses of 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphinane-2-oxide and triethylamine in S11 are (140-190)% and (75-90)% of the mass of 2,2-bis(bromomethyl)-1,3-propanediol, respectively.

8. The method for preparing a high-elasticity and high-strength spandex fiber fabric according to claim 6, characterized in that: The masses of 6-nitrobenzimidazole and tetrabutylammonium bromide in S12 are (120-180)% and (9-14)% of the mass of the 2,2-bis(bromomethyl)-1,3-phosphate intermediate, respectively.

Images