Antibacterial layered composite elastic fabric and preparation method thereof

Abstract

The invention relates to the technical field of layered materials, in particular to an antibacterial layered composite elastic fabric and a preparation method thereof. The defects that an existing layered fabric is poor in antibacterial property and elasticity are overcome. The preparation method comprises the following steps: preparing modified spandex fiber yarns by taking polytetrahydrofuran ether glycol, diphenylmethane diisocyanate and modified microcrystalline cellulose as raw materials; preparing modified polyester fiber yarns by taking terephthalic acid, ethylene glycol, 1, 4-butanediol, isophthalic acid and nano silicon dioxide as raw materials; plying the modified polyester fiber yarns and the modified spandex fiber yarns, and weaving to obtain an outer-layer fabric; performing pretreatment, dipping and heat treatment on the outer layer fabric to obtain an outer layer finished fabric; performing dipping and heat treatment on the inner-layer fabric to obtain an inner-layer finished fabric; the antibacterial layered composite elastic fabric obtained by laminating and compounding the outer-layer finishing fabric and the inner-layer finishing fabric has strong antibacterial property and strong elasticity, and is suitable for manufacturing outdoor textiles.

Description

Technical Field

[0001] The invention relates to the technical field of layered materials, in particular to an antibacterial layered composite elastic fabric and a preparation method thereof. Background Art

[0002] In the textile field, both single-layer fabrics and layered fabrics are widely used. Single-layer fabrics are common in light summer clothing, and their good breathability brings people a refreshing experience. For example, short-sleeved shirts made of ordinary cotton single-layer fabrics are comfortable to wear in hot weather. Layered fabrics are widely used in autumn and winter clothing, functional clothing, and household items. For example, some home clothes use a double-layer fabric structure. The outer layer is blended to ensure breathability, and the inner layer is brushed to form an air insulation layer, which significantly improves the warmth effect. Compared with single-layer fabrics, layered fabrics have obvious advantages. They can achieve a variety of functional combinations. Through the compounding of different material layers, they can also give the fabrics additional properties such as antibacterial, windproof, and waterproof.

[0003] With the improvement of people's economy and quality of life, more and more people like outdoor sports, and the requirements for outdoor textile products are becoming increasingly stringent. Not only do they expect outdoor textiles to have basic warmth and breathability functions, but they also desire them to have good antibacterial properties to ensure health, and at the same time have high elasticity to meet the needs of daily activities and sports. However, the current existing layered fabrics have many problems in terms of antibacterial and elasticity. In terms of antibacterial properties, ordinary fabric materials are easily eroded by microorganisms. Even if antibacterial agents are added, the antibacterial effect is often difficult to last due to uneven distribution and poor durability. Some antibacterial agents also pose health and environmental risks. In terms of elasticity, the differences in the material properties of each layer and the problem of the interlayer bonding method result in inconsistent deformation of each layer during stretching, which is prone to delamination and breakage, and cannot meet the requirements of human movement for high elasticity and recovery.

[0004] Therefore, an antibacterial layered composite elastic fabric and a preparation method thereof are proposed. Summary of the invention

[0005] The purpose of the present invention is to provide an antibacterial layered composite elastic fabric and a preparation method thereof. The present invention uses polytetramethylene ether glycol, diphenylmethane diisocyanate, and modified microcrystalline cellulose as raw materials to prepare modified spandex fiber yarn; uses terephthalic acid, ethylene glycol, 1,4-butanediol, isophthalic acid, and nano-silicon dioxide as raw materials to prepare modified polyester fiber yarn; the outer layer fabric is obtained by plying and weaving the modified polyester fiber yarn and the modified spandex fiber yarn; the outer layer fabric is subjected to pretreatment, impregnation, and heat treatment to obtain the outer layer finishing fabric; the inner layer fabric is subjected to impregnation and heat treatment to obtain the inner layer finishing fabric; the outer layer finishing fabric is bonded and composited with the inner layer finishing fabric to obtain the antibacterial layered composite elastic fabric, which has strong antibacterial properties and strong elasticity and is suitable for the production of outdoor textiles.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] In one aspect, the present invention provides a method for preparing an antibacterial layered composite elastic fabric, which specifically comprises the following steps:

[0008] S1: plying and weaving cotton fiber yarn and modified spandex fiber yarn to obtain an inner layer fabric; plying and weaving modified polyester fiber yarn and modified spandex fiber yarn to obtain an outer layer fabric;

[0009] S2 pre-treats, impregnates, and heat-treats the outer fabric to obtain an outer finished fabric; and impregnates and heat-treats the inner fabric to obtain an inner finished fabric;

[0010] S3: laminating and compounding the outer layer finishing fabric and the inner layer finishing fabric to obtain the antibacterial layered composite elastic fabric;

[0011] Modified spandex fiber yarn was prepared using polytetramethylene ether glycol, diphenylmethane diisocyanate, and modified microcrystalline cellulose as raw materials; modified polyester fiber yarn was prepared using terephthalic acid, ethylene glycol, 1,4-butanediol, isophthalic acid, and nano-silicon dioxide as raw materials; and modified microcrystalline cellulose was prepared using microcrystalline cellulose, silver nitrate, and polydimethyldiallylammonium chloride as raw materials.

[0012] Preferably, the preparation method of the modified spandex fiber yarn is as follows: polytetramethylene glycol is added to a reaction kettle, diphenylmethane diisocyanate and dibutyltin dilaurate are added at 55-65°C after vacuum dehydration, and the reaction is performed for 2 hours to generate a prepolymer; 1,4-butanediol is added to the prepolymer and the reaction is performed for 2.5 hours to obtain a spandex copolymer; the spandex copolymer is dissolved in N,N-dimethylacetamide and then modified microcrystalline cellulose and an antioxidant are added, and the spinning solution is sheared and dispersed for 30 minutes to obtain a spinning solution, and the spinning solution is spun and twisted to obtain the modified spandex fiber yarn, wherein the spinning temperature is set to 240°C.

[0013] Preferably, the preparation method of modified microcrystalline cellulose is as follows: after dispersing microcrystalline cellulose in deionized water, silver nitrate is added and stirred for 30 minutes, glucose is subsequently added, and the mixture is reacted at 85-95°C for 1 hour, followed by centrifugation and drying to obtain silver-loaded microcrystalline cellulose; after dispersing silver-loaded microcrystalline cellulose in deionized water, sodium hydroxide is added and stirred for 30 minutes, and then modified polydimethyldiallylammonium chloride is added, and the mixture is reacted at 70°C for 5 hours to obtain a reaction solution, the reaction solution is centrifuged, and the precipitate is washed and dried to obtain modified microcrystalline cellulose.

[0014] Preferably, the preparation method of modified polydimethyldiallyl ammonium chloride is: dissolving 3 parts of polydimethyldiallyl ammonium chloride in 50 parts of deionized water and then cooling to 5°C to obtain a reaction solution; adding 5 parts of a 27-33% by mass peracetic acid aqueous solution to the reaction solution; adding isopropanol for precipitation, filtering, washing and drying the precipitate to obtain modified polydimethyldiallyl ammonium chloride.

[0015] Preferably, the preparation method of the modified polyester fiber yarn is as follows: in a reactor, terephthalic acid, ethylene glycol, 1,4-butanediol, isophthalic acid, zinc acetate and antimony trioxide are added in sequence, and then pre-reacted at 150°C for 30 minutes, and then the temperature is raised to 240-260°C for reaction for 4 hours to obtain a reaction system; pretreated nano-silica and stearic acid are added to the reaction system, blended at a stirring speed of 300 rpm for 5 minutes, and then heated to 280°C for reaction for 2-2.5 hours to obtain a melt; the melt is extruded through a screw extruder, cooled, pelletized, and dried to obtain modified polyester chips; the modified polyester chips are heated and melted, and then spun and twisted to obtain modified polyester fiber yarn; the preparation method of pretreated nano-silica is as follows: nano-silica is dispersed in anhydrous ethanol, KH560 is added, stirred for reaction for 2 hours, filtered and dried after the reaction is completed, and pretreated nano-silica is obtained.

[0016] Preferably, the preparation method of the outer layer finished fabric is: pre-treating the outer layer fabric to obtain the pre-treated fabric, immersing the pre-treated fabric in the finishing liquid for 15 minutes, and then performing immersion rolling, drying, and baking to obtain the outer layer finished fabric; by weight, the pre-treatment method is: adding 7-8 parts of KH550 and 6-8 parts of nano-silicon dioxide to 90 parts of anhydrous ethanol, ultrasonically stirring for 60 minutes to obtain a dispersion; after immersing the outer layer fabric in the dispersion for 30 minutes, drying and heat-treating it to obtain the pre-treated fabric.

[0017] Preferably, the preparation method of the inner layer finishing fabric is: immersing the inner layer fabric in the finishing liquid for 15 minutes, and then performing a baking treatment through immersion rolling, drying, and then baking to obtain the inner layer finishing fabric, wherein the baking temperature is 130-150°C and the time is 2 minutes.

[0018] Preferably, the preparation method of the finishing liquid is as follows: by weight, 150 parts of polyurethane elastomer aqueous dispersion are added to deionized water, and after stirring at 200 rpm for 10 minutes, 6-10 parts of polyhexamethylene biguanide, 3 parts of melamine formaldehyde resin crosslinking agent, 8-10 parts of modified waterproofing agent, 3 parts of silicone emulsion softener, 0.7 parts of sodium polyacrylate dispersant, and 0.45 parts of fatty alcohol polyoxyethylene ether are added in sequence, and stirred for 30 minutes. Deionized water is added to adjust the total concentration to 20%, and then the finishing liquid is allowed to stand for defoaming to obtain.

[0019] Preferably, the preparation method of the modified waterproofing agent is as follows: by weight, 100 parts of polycaprolactone diol with a molecular weight of 1000-2000 and 30 parts of N-methylpyrrolidone are mixed and stirred to obtain a mixture; the temperature is lowered to 55-65°C, 40 parts of diphenylmethane diisocyanate are added to the mixture and reacted for 2 hours to obtain a prepolymer; the temperature is lowered to 50°C, 10 parts of 1,4-butanediol are added to the prepolymer, the reaction is continued for 2 hours, and then 0.5 parts of triethylamine are added, the reaction is stirred for 30 minutes, and the mixture is cooled to obtain a modified waterproofing agent.

[0020] On the other hand, the present invention provides an antibacterial layered composite elastic fabric, the antibacterial layered composite elastic fabric comprises an inner layer fabric and an outer layer fabric; the inner layer fabric comprises cotton fiber yarn and modified spandex fiber yarn; the outer layer fabric comprises modified polyester fiber yarn and modified spandex fiber yarn; by weight,

[0021] The raw materials of modified spandex fiber yarn include: 90-110 parts of polytetramethylene ether glycol, 45-55 parts of diphenylmethane diisocyanate, 10-15 parts of 1,4-butanediol, and 8-10 parts of modified microcrystalline cellulose;

[0022] The raw materials of the modified polyester fiber yarn include: 90-110 parts of terephthalic acid, 45-55 parts of ethylene glycol, 13-17 parts of 1,4-butanediol, 4-6 parts of isophthalic acid, 4-6 parts of pretreated nano-silicon dioxide, and 0.5 parts of stearic acid;

[0023] The modified microcrystalline cellulose raw materials include: microcrystalline cellulose, silver nitrate, polydimethyldiallylammonium chloride;

[0024] The pre-treated nano-silicon dioxide raw material includes: 3 parts of nano-silicon dioxide and 1.5 parts of KH560.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. In the present invention, microcrystalline cellulose is used as a carrier, and its surface hydroxyl groups are used to adsorb silver ions and form nanosilver particles through in-situ reduction, thereby giving the fiber contact antibacterial activity; the epoxy groups of epoxy-modified polydimethyldiallyl ammonium chloride react with cellulose hydroxyl groups to form covalent bonds; at the same time, its amino groups react with the isocyanate groups of the polyurethane prepolymer to form urea bonds, thereby constructing a cellulose-polydimethyldiallyl ammonium chloride-polyurethane triple chemical bonding network, which not only stably loads nanosilver to inhibit washing loss, but also enhances the breaking strength through stress transfer between rigid cellulose and flexible polyurethane chains; during the spinning process, high-temperature solvent volatilization prompts cellulose to be arranged in an orderly manner along the fiber axis to form a reinforced skeleton, and the cationic properties of polydimethyldiallyl ammonium chloride are dispersed through electrostatic regulation of fillers to ensure the uniformity of fiber elasticity, ultimately achieving a synergistic improvement in antibacterial, mechanical and elastic properties.

[0027] 2. In the present invention, 1,4-butanediol is introduced as a flexible segment in the preparation of modified polyester fiber. Its long carbon chain reduces the intermolecular force of polyester and enhances the mobility of the segment. At the same time, the meta-substituted structure of isophthalic acid destroys the rigid and orderly arrangement of terephthalic acid and inhibits the formation of crystalline regions. The two synergistically reduce the rigidity of the material and improve the resilience. In addition, nano-silicon dioxide forms a covalent bond with the polyester matrix through a silane coupling agent, and its rigid particles are dispersed in a flexible matrix with low crystallinity. Through stress transmission and hindering crack propagation, the mechanical properties of the fiber are improved, and finally the synergistic enhancement of elasticity and mechanical properties is achieved.

[0028] 3. In the present invention, during the pretreatment of the outer fabric, the silane coupling agent and nano-silica are co-deposited to construct a micro-nano rough structure, reduce the surface energy and introduce amino active sites; the modified waterproofing agent is copolymerized with the flexible chain segment of polycaprolactone diol and the rigid chain segment of isocyanate to construct a hydrophobic polyurethane network, and the residual isocyanate group at its end reacts with the amino group and hydroxyl group on the surface of the pretreated fiber during high-temperature baking to form a chemically bonded interface, which not only gives the fabric a long-lasting water-repellent ability, but also enhances the bonding strength between fibers through covalent bond bridging.

[0029] 4. In the present invention, polyhexamethylene biguanide can destroy bacterial cell membranes and achieve initial high-efficiency antibacterial effect in the early stage of fabric use; and after repeated washing, antibacterial components such as nanosilver fixed by chemical bonds in the spandex fiber are slowly released from the inside of the fiber to supplement the surface antibacterial activity, and the internal and external synergy achieves a multi-level long-term antibacterial effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the breaking strength and breaking elongation of Example 1, Example 6, Examples 8-10, and Comparative Examples 6-7 of the present invention. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] See also Figure 1 The present invention provides an antibacterial layered composite elastic fabric and a preparation method thereof, and the technical scheme is as follows:

[0033] Example 1

[0034] Preparation of modified polydimethyldiallylammonium chloride

[0035] 3 parts of high molecular weight polydimethyldiallyl ammonium chloride are dissolved in 50 parts of deionized water and then cooled to 5°C; 5 parts of 30% by mass peracetic acid aqueous solution are slowly added dropwise; isopropanol is added for precipitation, and after filtering, the precipitate is washed and dried to obtain modified polydimethyldiallyl ammonium chloride.

[0036] Preparation of modified microcrystalline cellulose

[0037] Disperse 10 parts of microcrystalline cellulose in 100 parts of deionized water, stir for 30 minutes, add 0.5 parts of silver nitrate and stir for 30 minutes, then add 1 part of glucose, react at 85°C for 1 hour, centrifuge and dry to obtain silver-loaded microcrystalline cellulose; disperse the silver-loaded microcrystalline cellulose in 100 parts of deionized water, add 0.5 parts of sodium hydroxide and stir for 30 minutes; add modified polydimethyldiallylammonium chloride, react at 70°C for 5 hours, centrifuge, wash and dry to obtain modified microcrystalline cellulose.

[0038] Preparation of modified spandex fiber yarn

[0039] 90 parts of polytetramethylene glycol with a molecular weight of 2000 were added to the reactor, and vacuum dehydrated at 80°C for 2 hours; the temperature was lowered to 60°C, 40 parts of diphenylmethane diisocyanate and 0.1 parts of dibutyltin dilaurate catalyst were added, and the reaction was carried out under nitrogen protection for 2 hours to generate a prepolymer; 10 parts of 1,4-butanediol were added to the prepolymer, and the reaction was continued for 3 hours to obtain a spandex copolymer; the polyurethane copolymer was dissolved in 485 parts of N,N-dimethylacetamide, and then 10 parts of modified microcrystalline cellulose and an antioxidant (antioxidant Irganox 1010), the amount of antioxidant is 0.5% of the total mass of the spinning solution, and the spinning solution is stirred for 30 minutes using a high shear disperser. The spinning solution is spun and twisted at a spinning temperature of 245°C and a spinning speed of 750m / min to obtain a modified spandex fiber yarn. The twist of the modified spandex fiber yarn is 25 twists / 10cm and the linear density is 35dtex.

[0040] Preparation of modified polyester fiber yarn

[0041] Preparation of pretreated nano-silica: 4 parts of nano-silica were dispersed in anhydrous ethanol, and then 1 part of KH-560 was added. The reaction was continued with stirring for 2 hours. After the reaction was completed, the mixture was filtered and dried to obtain pretreated nano-silica.

[0042] In a reactor, 90 parts of terephthalic acid, 45 parts of ethylene glycol, 17 parts of 1,4-butanediol, 4 parts of isophthalic acid, 0.4 parts of zinc acetate and 0.3 parts of antimony trioxide catalyst were added in sequence, reacted at 150°C for 30 minutes, and then heated to 250°C for 4 hours to obtain a reaction system; 4 parts of pretreated nano-silicon dioxide and 0.5 parts of stearic acid were added to the reaction system, blended at a stirring speed of 300 rpm for 5 minutes, heated to 280°C and reacted for 2.5 hours to obtain a melt; the melt was extruded through a screw extruder, cooled, pelletized and dried to obtain modified polyester chips; the modified polyester chips were heated and melted at 285°C, spun and twisted at a spinning temperature of 280°C and a spinning speed of 800 m / min to obtain modified polyester fiber yarn, the twist of the modified polyester fiber yarn was 30 twists / 10cm, and the linear density was 40 dtex.

[0043] Preparation of inner and outer fabrics

[0044] Inner fabric: The yarn counts of modified spandex fiber yarn and cotton fiber yarn are both 50S in British standard; the mass ratio of modified spandex fiber yarn to cotton fiber yarn is 4:1; the gram weight of the inner fabric is 80g / m 2 .

[0045] Outer fabric: modified spandex yarn with a British count of 50S, modified polyester yarn with a British count of 60S; the mass ratio of modified spandex yarn to cotton yarn is 1:1; the weight of the inner fabric is 100g / m 2 .

[0046] Preparation of finishing solution

[0047] 100 parts of polycaprolactone diol with a molecular weight of 1000 and 30 parts of N-methylpyrrolidone were mixed, heated to 90°C and stirred for 1 hour; the system was cooled to 60°C, 40 parts of diphenylmethane diisocyanate were added and reacted at 60°C for 2 hours to obtain a prepolymer, the system was cooled to 50°C, 10 parts of 1,4-butanediol were added dropwise, the reaction was continued at 50°C for 2 hours, and then 0.5 parts of triethylamine were added, the reaction was stirred for 30 minutes, and the modified waterproofing agent was obtained.

[0048] 150 parts of polyurethane elastomer aqueous dispersion (Covestro Bayhydrol UH2890) were added to deionized water, and after stirring at 200 rpm for 10 min, 1 part of purified polyhexamethylene biguanide, 3 parts of melamine formaldehyde resin crosslinker (Yadina YDN598), 8 parts of modified waterproofing agent, 3 parts of silicone emulsion softener (Qimin Chemical Qiquan), 0.7 parts of sodium polyacrylate dispersant (BASF Dispex N40) and 0.45 parts of fatty alcohol polyoxyethylene ether penetrant were added in sequence, and stirred for 30 min. Deionized water was added to adjust the total concentration to 20%, and the finishing solution was obtained by standing and defoaming.

[0049] Preparation of outer finishing fabrics

[0050] The outer layer fabric is pretreated to obtain the pretreated fabric, and the pretreated fabric is immersed in the finishing liquid, the bath ratio of the fabric to the finishing liquid is 20:1, and after immersion for 15 minutes, it is subjected to immersion and rolling, one immersion and one rolling, and the rolling rate is 70%, and then drying and baking are carried out, the drying temperature is 80℃, the time is 10 minutes; the baking temperature is 120℃, and the time is 3 minutes. The outer layer finishing fabric is obtained; the pretreatment method is: 7 parts of KH550 and 6 parts of nano silicon dioxide are added to 90 parts of anhydrous ethanol, and ultrasonic stirring is performed for 60 minutes to obtain a dispersion; the outer layer fabric is immersed in the dispersion for 30 minutes, and then dried and heat-treated to obtain the pretreated fabric.

[0051] Preparation of inner finishing fabrics

[0052] The inner layer fabric is immersed in the finishing liquid, and the bath ratio of the fabric to the finishing liquid is 20:1. After immersion for 15 minutes, it is immersed and rolled, one immersion and one rolling, and the rolling rate is 60%. After drying, it is baked at a drying temperature of 80°C and a time of 10 minutes; the baking temperature is 130°C and a time of 2 minutes to obtain the inner layer finished fabric.

[0053] The outer finishing fabric and the inner finishing fabric are laminated and aligned, and the inner fabric and the outer fabric are sewn together by a polyester sewing thread through a multi-layer fabric quilting machine to obtain an antibacterial layered composite elastic fabric.

[0054] The differences between Example 2-11 and Example 1 are shown in Table 1.

[0055] Table 1 Parameters of Examples 1-11

[0056]

[0057] The difference between Example 12 and Example 10 is that when preparing the dispersion used for pretreatment of the outer fabric, the amount of KH550 is 7.5 parts and the amount of nano-silicon dioxide is 7 parts; when preparing the modified waterproofing agent, the molecular weight of the polycaprolactone diol is 1500 when preparing the finishing liquid, and the reaction temperature is 60°C when preparing the prepolymer; when preparing the finishing liquid, the amount of the modified waterproofing agent added is 9 parts.

[0058] The difference between Example 13 and Example 10 is that when preparing the dispersion used for pretreatment of the outer fabric, the amount of KH550 used is 8 parts and the amount of nano-silicon dioxide is 8 parts; when preparing the modified waterproofing agent, the molecular weight of the polycaprolactone diol when preparing the finishing liquid is 2000, and the reaction temperature when preparing the prepolymer is 65°C; when preparing the finishing liquid, the amount of modified waterproofing agent added is 10 parts.

[0059] The difference between Example 14 and Example 10 is that when preparing the dispersion used for pretreatment of the outer fabric, the amount of KH550 used is 7.5 parts and the amount of nano-silicon dioxide is 7 parts; when preparing the modified waterproofing agent, the molecular weight of the polycaprolactone diol when preparing the finishing liquid is 1000, and the reaction temperature when preparing the prepolymer is 60°C; when preparing the finishing liquid, the amount of modified waterproofing agent added is 10 parts.

[0060] The difference between Example 15 and Example 14 is that when the finishing liquid is prepared, the amount of polyhexamethylene biguanide added is 8 parts.

[0061] The difference between Example 16 and Example 14 is that the amount of polyhexamethylene biguanide added in the preparation of the finishing liquid is 10 parts.

[0062] The difference between Example 17 and Example 16 is that different amounts of raw materials are used in the preparation of the modified spandex fiber yarn: 100 parts of polytetramethylene ether glycol, 50 parts of diphenylmethane diisocyanate, 13 parts of 1,4-butanediol, and 9 parts of modified microcrystalline cellulose;

[0063] The modified polyester fiber yarn was prepared with different amounts of raw materials: 100 parts of terephthalic acid, 50 parts of ethylene glycol, 21 parts of 1,4-butanediol, 5 parts of isophthalic acid, and 5 parts of pretreated nano-silica.

[0064] The difference between Example 18 and Example 16 is that different amounts of raw materials are used in the preparation of the modified spandex fiber yarn: 110 parts of polytetramethylene ether glycol, 55 parts of diphenylmethane diisocyanate, 15 parts of 1,4-butanediol, and 10 parts of modified microcrystalline cellulose;

[0065] The modified polyester fiber yarn was prepared with different amounts of raw materials: 110 parts of terephthalic acid, 55 parts of ethylene glycol, 24 parts of 1,4-butanediol, 6 parts of isophthalic acid, and 6 parts of pretreated nano-silica.

[0066] The difference between Example 19 and Example 16 is that different amounts of raw materials are used in the preparation of the modified spandex fiber yarn: 100 parts of polytetramethylene ether glycol, 50 parts of diphenylmethane diisocyanate, 13 parts of 1,4-butanediol, and 9 parts of modified microcrystalline cellulose;

[0067] The modified polyester fiber yarn was prepared with different amounts of raw materials: 110 parts of terephthalic acid, 55 parts of ethylene glycol, 24 parts of 1,4-butanediol, 6 parts of isophthalic acid, and 6 parts of pretreated nano-silica.

[0068] The difference between Comparative Example 1 and Example 1 is that modified microcrystalline cellulose is not added during the preparation of the modified spandex fiber yarn.

[0069] The difference between Comparative Example 2 and Example 1 is that during the preparation of the modified microcrystalline cellulose, no modified polydimethyldiallylammonium chloride is added.

[0070] The difference between Comparative Example 3 and Example 1 is that no silver loading treatment is performed during the preparation of the modified microcrystalline cellulose.

[0071] The difference between Comparative Example 4 and Example 1 is that 1,4-butanediol is not added during the preparation of the modified polyester fiber.

[0072] The difference between Comparative Example 5 and Example 1 is that isophthalic acid is not added during the preparation of the modified polyester fiber.

[0073] The difference between Comparative Example 6 and Example 1 is that no pretreated nano-silica is added during the preparation of the modified polyester fiber.

[0074] The difference between Comparative Example 7 and Example 1 is that the nano-silicon dioxide is not pretreated during the preparation of the modified polyester fiber.

[0075] The difference between Comparative Example 8 and Example 1 is that the outer fabric is not pretreated.

[0076] The difference between Comparative Example 9 and Example 1 is that the baking temperature during the preparation of the inner layer finishing fabric and the outer layer finishing fabric is 80°C.

[0077] The difference between Comparative Example 10 and Example 1 is that no modified waterproofing agent is added to the finishing liquid.

[0078] The difference between Comparative Example 11 and Example 1 is that, during the preparation of the finishing liquid, hexadecyltrimethylammonium chloride is used to replace polyhexamethylene biguanide and the added amount is the same.

[0079] The difference between Comparative Example 12 and Example 1 is that the molecular weight of the polyethyllactone diol in the preparation process of the modified waterproofing agent is 4000.

[0080] Test Example 1

[0081] Test objects: Examples 1-7, Comparative Examples 1-3, Comparative Example 9, Comparative Example 11, Examples 15-16.

[0082] Test method: The antibacterial rate is determined according to GB / T 20944.3-2008 "Evaluation of antibacterial properties of textiles Part 3: Oscillation method", and the bacteria species used are Escherichia coli. The final test results are shown in Table 2.

[0083] Table 2 Antibacterial rate test results

[0084]

[0085] Comparative Example 1 does not add modified microcrystalline cellulose, resulting in the lack of a triple chemical bonding network (cellulose-polydimethyldiallyl ammonium chloride-polyurethane) in the spandex fiber, and the nanosilver cannot be stably loaded, relying only on the physical adsorption of the surface polyhexamethylene biguanide. After washing, the antibacterial agent is lost and there is no sustained-release supplement, resulting in a decrease in antibacterial performance. Comparative Example 2 does not use modified polydimethyldiallyl ammonium chloride, resulting in only weak hydrogen bonding between microcrystalline cellulose and polyurethane, and the lack of epoxy covalent bonds makes nanosilver easy to fall off, and the antibacterial activity is reduced after washing. Comparative Example 3 does not use silver-loaded microcrystalline cellulose only as a physical filler, without the contact antibacterial effect of nanosilver, and the surface polyhexamethylene biguanide is lost after washing without inner layer supplementation, and the antibacterial performance is significantly reduced. Comparative Example 9 low-temperature baking results in insufficient curing of the crosslinking agent, and polyhexamethylene biguanide is attached by hydrogen bonds. After washing, insufficient binding force and loss lead to subsequent poor antibacterial durability. Comparative Example 11 Hexadecyltrimethylammonium chloride and the built-in cationic components of the fiber have charge repulsion, uneven distribution, and hydrophobic adsorption that is easily destroyed by water washing.

[0086] Test Example 2

[0087] Test objects: Example 1, Example 6, Examples 8-10, Comparative Examples 4-7.

[0088] Test method: The elastic recovery rate adopts FZ / T70006-2004 "Test method for elastic recovery rate of knitted fabrics"; the breaking strength and breaking elongation adopt ISO9073-3-1989 "Textile nonwoven fabric test method part 3: tensile strength and elongation determination". The final test results are shown in Table 3 and Figure 1 shown.

[0089] Table 3 Rebound elasticity and mechanical properties test results

[0090] serial number Elastic recovery rate (%) Example 1 70.5 Example 6 72.5 Example 8 73.3 Example 9 73.7 Example 10 74.1 Comparative Example 4 62.5 Comparative Example 5 68.1 Comparative Example 6 68.5 Comparative Example 7 68.8

[0091] In comparative example 4, the lack of 1,4-butanediol flexible chain segment enhances the rigidity of the polyester molecular chain, the expansion of the crystal region restricts the movement of the chain segment, and the elastic recovery rate decreases. In comparative example 5, the lack of isophthalic acid meta-substitution leads to a highly ordered arrangement of terephthalic acid, and the large-sized crystal region restricts the movement of the chain segment, and the elastic recovery rate decreases. However, the effect of isophthalic acid is small, and it needs to cooperate with 1,4-butanediol to enhance the elastic recovery rate. Figure 1 As shown, the mechanical properties of the materials were tested in Comparative Examples 6-7. The lack of pre-treated nano-silica in Comparative Example 6 resulted in the lack of fillers that enhance the mechanical properties, reduced stress transfer efficiency, and decreased breaking strength. The surface hydroxyl groups of the unpre-treated nano-silica in Comparative Example 7 were weakly adsorbed to the polyester matrix, and the poor dispersion of the filler resulted in deterioration of the mechanical properties.

[0092] Test Example 3

[0093] Test objects: Example 1, Examples 12-14, Comparative Example 8, Comparative Example 10, Comparative Example 12.

[0094] Test method: The waterproof performance test adopts the water dipping method of GB / T 4745-2012 Testing and evaluation of waterproof performance of textiles. The final test results are shown in Table 4.

[0095] Table 4 Waterproof performance test results

[0096] serial number Waterproof performance (grade) Example 1 Level 5 Example 12 Level 5 Example 13 Level 5 Embodiment 14 Level 5 Comparative Example 8 Level 3 Comparative Example 10 Level 3 Comparative Example 12 Level 3

[0097] In Comparative Example 8, the outer fabric was not pretreated, resulting in the loss of the micro-nano rough structure constructed by the co-deposition of silane coupling agent and nano-silicon dioxide, the fiber surface energy was not reduced, and no amino active sites were introduced; the terminal isocyanate group of the modified waterproofing agent could not form a chemical bonding interface due to the lack of amino and hydroxyl groups on the pretreated fiber surface, and was only attached by physical adsorption. The insufficient interface bonding force during the washing process caused the waterproofing agent to fall off, and the water-repellent ability was significantly reduced. In Comparative Example 10, the lack of modified waterproofing agent resulted in the failure to form a hydrophobic polyurethane network, and water molecules directly penetrated the fiber gaps. In Comparative Example 12, the high molecular weight polycaprolactone diol had insufficient crosslinking density, and the porosity of the hydrophobic network increased, which could not tightly cover the fiber surface structure.

[0098] Test Example 4 Comprehensive Test

[0099] Test Subject: Examples 17-19

[0100] Test method: The test method refers to test examples 1-3. The final test results are shown in Table 5.

[0101] Table 5 Comprehensive performance test results

[0102]

[0103] Through the optimization of various process parameters and component dosages, it can be seen that under the conditions of Example 19, the performance of the antibacterial layered composite elastic fabric finally prepared is the best. The present invention achieves a comprehensive improvement in antibacterial properties, mechanical properties and functional durability through multi-scale structural design and chemical synergistic effects. First, using microcrystalline cellulose as a carrier, the surface hydroxyl groups are fixed to nanosilver particles by in-situ reduction, and a triple chemical bonding network is constructed with the help of epoxy-modified polydimethyldiallyl ammonium chloride, which not only stabilizes nanosilver through covalent bonds to inhibit washing loss, but also synergistically enhances the breaking strength through the stress transfer of the rigid cellulose skeleton and the flexible polyurethane chain. Secondly, in the polyester molecular design, the 1,4-butanediol flexible chain segment reduces the intermolecular force, and the isophthalic acid destroys the rigid ordered arrangement to inhibit crystallization, and the two synergistically improve the resilience; the silane-coupled nanosilica is combined with the flexible matrix through covalent bonds, and the rigid particles hinder the crack propagation, so as to achieve the simultaneous enhancement of the breaking strength and fatigue resistance. In the pretreatment of the outer fabric, silane coupling agent and nano-silicon dioxide are co-deposited to construct a micro-nano rough structure, combined with the hydrophobic network of polycaprolactone diol / isocyanate copolymer, and the chemically bonded interface is used to give it a durable water-repellent ability. The antibacterial system adopts a dual mechanism: polyhexamethylene biguanide destroys the bacterial membrane in the early stage to achieve rapid antibacterial inhibition, and the chemically bonded nano-silver is slowly released with water washing to supplement the activity, and the internal and external synergy ensures the durability of antibacterial. Each component is regulated by chemical bonding and microstructure to achieve multi-performance synergistic optimization.

[0104] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing an antibacterial layered composite elastic fabric, characterized in that: The specific steps include: S1: plying and weaving cotton fiber yarn and modified spandex fiber yarn to obtain inner fabric; plying and weaving modified polyester fiber yarn and modified spandex fiber yarn to obtain outer fabric; S2: pre-treating, impregnating and heat-treating the outer fabric to obtain outer finishing fabric; impregnating and heat-treating the inner fabric to obtain inner finishing fabric; S3: laminating and compounding the outer finishing fabric and the inner finishing fabric to obtain the antibacterial layered composite elastic fabric; Modified spandex fiber yarn was prepared using polytetramethylene ether glycol, diphenylmethane diisocyanate, and modified microcrystalline cellulose as raw materials; modified polyester fiber yarn was prepared using terephthalic acid, ethylene glycol, 1,4-butanediol, isophthalic acid, and nano-silicon dioxide as raw materials; and modified microcrystalline cellulose was prepared using microcrystalline cellulose, silver nitrate, and polydimethyldiallylammonium chloride as raw materials.

2. The method for preparing an antibacterial layered composite elastic fabric according to claim 1, characterized in that: The preparation method of the modified spandex fiber yarn is as follows: adding polytetramethylene glycol to a reaction kettle, adding diphenylmethane diisocyanate and dibutyltin dilaurate at 55-65°C after vacuum dehydration, and reacting for 2 hours to generate a prepolymer; adding 1,4-butanediol to the prepolymer and reacting for 2.5 hours to obtain a spandex copolymer; dissolving the spandex copolymer in N,N-dimethylacetamide and then adding the modified microcrystalline cellulose and an antioxidant, shearing and dispersing for 30 minutes to obtain a spinning solution, and spinning and twisting the spinning solution to obtain the modified spandex fiber yarn, wherein the spinning temperature is set to 240°C.

3. The method for preparing an antibacterial layered composite elastic fabric according to claim 1, characterized in that: The preparation method of modified microcrystalline cellulose is as follows: the microcrystalline cellulose is dispersed in deionized water, silver nitrate is added, and the mixture is stirred for 30 minutes, glucose is then added, and the mixture is reacted at 85-95° C. for 1 hour, and then centrifuged and dried to obtain silver-loaded microcrystalline cellulose; The silver-loaded microcrystalline cellulose is dispersed in deionized water, sodium hydroxide is added, and stirred for 30 minutes, and then modified polydimethyldiallylammonium chloride is added, and the reaction is carried out at 70° C. for 5 hours to obtain a reaction solution, the reaction solution is centrifuged, and the precipitate is washed and dried to obtain the modified microcrystalline cellulose.

4. The method for preparing an antibacterial layered composite elastic fabric according to claim 3, characterized in that: The preparation method of the modified polydimethyldiallyl ammonium chloride comprises the following steps: dissolving 3 parts of polydimethyldiallyl ammonium chloride in 50 parts of deionized water and then cooling the mixture to 5°C to obtain a reaction solution; dripping 5 parts of a 27-33% by mass peracetic acid aqueous solution into the reaction solution; adding isopropanol for precipitation, filtering, washing and drying the precipitate to obtain the modified polydimethyldiallyl ammonium chloride.

5. The method for preparing an antibacterial layered composite elastic fabric according to claim 1, characterized in that: The preparation method of the modified polyester fiber yarn is as follows: in a reaction kettle, terephthalic acid, ethylene glycol, 1,4-butanediol, isophthalic acid, zinc acetate and antimony trioxide are added in sequence, and then pre-reacted at 150°C for 30 minutes, and then heated to 240-260°C for reaction for 4 hours to obtain a reaction system; pretreated nano-silicon dioxide and stearic acid are added to the reaction system, mixed at a stirring speed of 300 rpm for 5 minutes, and then heated to 280°C for reaction for 2-2.5 hours to obtain a melt; the melt is extruded through a screw extruder, cooled, pelletized and dried to obtain modified polyester chips; the modified polyester chips are heated and melted, and then spun and twisted to obtain the modified polyester fiber yarn; the preparation method of the pretreated nano-silicon dioxide is as follows: nano-silicon dioxide is dispersed in anhydrous ethanol, KH560 is added, stirred for reaction for 2 hours, filtered and dried after the reaction is completed, and the pretreated nano-silicon dioxide is obtained.

6. The method for preparing an antibacterial layered composite elastic fabric according to claim 1, characterized in that: The preparation method of the outer layer finished fabric is: pre-treating the outer layer fabric to obtain a pre-treated fabric, immersing the pre-treated fabric in a finishing liquid for 15 minutes, and then performing immersion rolling, drying, and baking to obtain the outer layer finished fabric; by weight, the pre-treatment method is: adding 7-8 parts of KH550 and 6-8 parts of nano silicon dioxide to 90 parts of anhydrous ethanol, ultrasonically stirring for 60 minutes to obtain a dispersion; immersing the outer layer fabric in the dispersion for 30 minutes, drying and heat-treating the fabric to obtain the pre-treated fabric.

7. The method for preparing an antibacterial layered composite elastic fabric according to claim 1, characterized in that: The preparation method of the inner layer finishing fabric is: immersing the inner layer fabric in the finishing liquid for 15 minutes, and then performing a rolling and drying process to obtain the inner layer finishing fabric, wherein the baking temperature is 130-150° C. and the time is 2 minutes.

8. The method for preparing an antibacterial layered composite elastic fabric according to claim 7, characterized in that: The preparation method of the finishing liquid is as follows: 150 parts by mass of polyurethane elastomer aqueous dispersion are added to deionized water, and after stirring at 200 rpm for 10 minutes, 6-10 parts of polyhexamethylene biguanide, 3 parts of melamine formaldehyde resin crosslinking agent, 8-10 parts of modified waterproofing agent, 3 parts of silicone emulsion softener, 0.7 parts of sodium polyacrylate dispersant, and 0.45 parts of fatty alcohol polyoxyethylene ether are added in sequence, and the mixture is stirred for 30 minutes. Deionized water is added to adjust the total concentration to 20%, and the mixture is allowed to stand for defoaming to obtain the finishing liquid.

9. The method for preparing an antibacterial layered composite elastic fabric according to claim 8, characterized in that: The preparation method of the modified waterproofing agent is as follows: by weight, 100 parts of polycaprolactone diol with a molecular weight of 1000-2000 and 30 parts of N-methylpyrrolidone are mixed and stirred to obtain a mixture; the temperature is lowered to 55-65° C., 40 parts of diphenylmethane diisocyanate are added to the mixture to react for 2 hours to obtain a prepolymer; the temperature is lowered to 50° C., 10 parts of 1,4-butanediol are added to the prepolymer, the reaction is continued for 2 hours, and then 0.5 parts of triethylamine are added, the reaction is stirred for 30 minutes, and the mixture is cooled to obtain the modified waterproofing agent.

10. An antibacterial layered composite elastic fabric, characterized in that: The antibacterial layered composite elastic fabric is prepared by the preparation method of claim 1; the antibacterial layered composite elastic fabric comprises an inner layer fabric and an outer layer fabric; the inner layer fabric comprises cotton fiber yarn and modified spandex fiber yarn; the outer layer fabric comprises modified polyester fiber yarn and the modified spandex fiber yarn; by weight, The raw materials of modified spandex fiber yarn include: 90-110 parts of polytetramethylene ether glycol, 45-55 parts of diphenylmethane diisocyanate, 10-15 parts of 1,4-butanediol, and 8-10 parts of modified microcrystalline cellulose; The raw materials of the modified polyester fiber yarn include: 90-110 parts of terephthalic acid, 45-55 parts of ethylene glycol, 17-24 parts of 1,4-butanediol, 4-6 parts of isophthalic acid, 4-6 parts of pretreated nano-silicon dioxide, and 0.5 parts of stearic acid; The modified microcrystalline cellulose raw materials include: microcrystalline cellulose, silver nitrate, polydimethyldiallylammonium chloride; The pretreated nano-silicon dioxide raw material comprises: 3 parts of nano-silicon dioxide and 1.5 parts of KH560.

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