Elastic sandwich knitted fabric and preparation method thereof

Abstract

The invention relates to the technical field of knitted fabrics, in particular to an elastic sandwich knitted fabric and a preparation method thereof, and the preparation method comprises the following steps: step 1, selecting modified polyester yarns as raw materials, spinning three 25D modified polyester yarns into polyester 75D / FDY, then taking the polyester 75D / FDY as raw materials of a surface layer and a bottom layer, and taking 30D modified polyester yarns as raw materials of a middle layer; according to the sandwich knitted fabric, the modified polyester yarn is adopted as the raw material, the modified polyester yarn is spun to form the polyester 75D / FDY, the 30D modified polyester yarn is adopted as the raw material of the middle layer and matched with the polyester 75D / FDY to serve as the raw material of the surface layer and the raw material of the bottom layer, and through matching between layers and optimization of the specific technology of the modified polyester yarn, the sandwich knitted fabric is obtained. The obtained sandwich knitted fabric can achieve coordinated improvement of elasticity, heat preservation and bursting strength, and the product is remarkable in ultraviolet resistance, weather resistance and stability.

Description

Technical Field

[0001] The present invention relates to the technical field of knitted fabrics, and particularly relates to a stretchable sandwich knitted fabric and a preparation method thereof. Background Art

[0002] The sandwich fabric is composed of three layers: the upper, middle and lower layers. The surface is usually designed with mesh holes. The middle layer is MOLO yarn connecting the surface and the bottom layer. The bottom layer is usually a densely woven flat surface, commonly known as "sandwich". For the existing sandwich knitted fabrics, the elastic performance is poor, and at the same time, the heat preservation and bursting strength of the products are poor. It is difficult to achieve the coordinated improvement of elasticity, heat preservation and bursting strength for the products, and the ultraviolet and weather resistance stability of the products is poor, which limits the use efficiency of the products. Summary of the Invention

[0003] Aiming at the defects of the prior art, the purpose of the present invention is to provide a stretchable sandwich knitted fabric and a preparation method thereof to solve the problems raised in the above background art.

[0004] The present invention adopts the following technical solutions to solve the technical problems: The present invention provides a preparation method of a stretchable sandwich knitted fabric, including the following steps: Step 1: Select modified polyester filaments as raw materials. Three 25D modified polyester filaments are spun to form polyester 75D / FDY. Subsequently, polyester 75D / FDY is used as the raw material for the surface layer and the bottom layer, and 30D modified polyester filaments are used as the raw material for the middle layer; Step 2: Set them in the arrangement mode from top to bottom of the surface layer, the middle layer and the bottom layer, and form a sandwich fabric body by integral knitting with a knitting machine; Step 3: Perform overfeeding treatment on the sandwich fabric body. The upper overfeeding amount is 55%, and the lower overfeeding amount is 15%. Finally, it is shaped at 180 °C for 30 s to obtain the stretchable sandwich knitted fabric.

[0005] Preferably, the preparation method of the modified polyester filaments is as follows: S01: Melting and co-mixing and extruding 85-90 parts of polyester resin, 9-11 parts of additives based on weather resistance continuous adjustment, and 5-8 parts of supplementary agents by weight. The extrusion temperature is 285-300 °C, and the extrusion pressure is 8 MPa to obtain polyester masterbatch; S02: Melting and spinning the polyester masterbatch and the toughening agent according to the weight ratio of 5:1. After the spinning is completed, the modified polyester filaments are obtained.

[0006] Preferably, the spinning speed of the melting and spinning treatment is 3000 m / min; the toughening agent is epoxy cyclohexyl polyether polyol.

[0007] Preferably, the preparation method of the additives based on weather resistance continuous adjustment is as follows: S11: preheating mullite at 55-60° C. for 1 hour to obtain preheated mullite; uniformly blending 3-5 parts of the preheated mullite, 2-4 parts of flaky talcum powder and 5-8 parts of 8% sodium citrate solution by weight to obtain a mullite blending solution; S12: Preparation of weathering and conditioning liquid: S12a: heat treating the nano-mica powder at 150-170° C. for 1 h, and then air-cooling to room temperature to obtain thermally improved nano-mica powder; S12b: 4-7 parts of heat-modified nano-mica powder, 5-8 parts of sodium hexametaphosphate solution, and 2-4 parts of nano-calcium carbonate are uniformly mixed by weight to obtain a weather-resistant liquid; S13: immersing the carbon nanotubes in a mullite-adjusted solution with a weight of 3-5 times the total weight of the carbon nanotubes and stirring, filtering and drying after the stirring is completed to obtain a carbon nanotube agent mixed with mullite; S14: the carbon nanotube agent adjusted with mullite and the weather-resistant liquid are mixed in a weight ratio of 5:3 and ball-milled at a speed of 1500 r / min for 2 h. After the ball milling is completed, the mixture is filtered and dried to obtain an additive based on weather-resistant continuous adjustment.

[0008] Preferably, the stirring speed of the stirring treatment is 350-400 r / min, and the stirring is for 2 hours; and the mass fraction of the sodium hexametaphosphate solution is 5-8%.

[0009] Preferably, the preparation method of the tonic is: S101: pretreating the silicon carbide with a sufficient amount of 8-10% by mass nitric acid solution for 1 hour at a treatment speed of 200 r / min. After the treatment, washing, filtering and drying are completed to obtain dry silicon carbide; 5-8 parts of dried silicon carbide, 1-2 parts of nano-silica sol and 6-10 parts of sodium lignin sulfonate solution are uniformly mixed by weight to obtain silicon carbide liquid; S102: subjecting silicon carbide liquid and the effect-adjusting and replenishing agent to ultrasonic treatment in a weight ratio of 5:3, filtering and drying after the treatment to obtain the effect-adjusting and replenishing agent.

[0010] Preferably, the mass fraction of the sodium lignin sulfonate solution is 4-6%; the ultrasonic power of the ultrasonic treatment is 350-400W, and the ultrasonic treatment is performed for 1 hour.

[0011] Preferably, the preparation method of the efficacy-regulating and replenishing agent is: 5-8 parts of boron nitride fiber and 2-3 parts of strontium titanate are mixed and added into 6-10 parts of sodium dodecylbenzene sulfonate solution by weight, and then 1-2 parts of zirconium oxide and 2-4 parts of sodium silicate solution are added and mixed thoroughly, and finally filtered and dried to obtain an effect-regulating replenisher.

[0012] Preferably, the mass fraction of the sodium dodecylbenzenesulfonate solution is 4-7%; the mass fraction of the sodium silicate solution is 2-5%.

[0013] The present invention also provides a stretchable sandwich knitted fabric prepared by the preparation method of the stretchable sandwich knitted fabric.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. The sandwich knitted fabric of the present invention uses modified polyester filaments as raw materials. The modified polyester filaments are spun to form polyester 75D / FDY, and 30D modified polyester filaments are used as the raw material for the middle layer, combined with polyester 75D / FDY as the raw materials for the surface layer and the bottom layer. Through the cooperation between layers and the optimization of the specific process of the modified polyester filaments, the obtained sandwich knitted fabric can achieve coordinated improvement of elasticity, heat preservation and bursting strength, and the product has remarkable ultraviolet and weather resistance stability effects; 2. The modified polyester filaments use polyester resin as the matrix, and are melt-blended and extruded into pellets through the cooperation of additives and supplementary agents based on weathering continuous adjustment, and then melt-spun to obtain modified polyester filaments. Through the mutual coordination of the additives and supplementary agents based on weathering continuous adjustment, the performance of the obtained modified polyester filament products is further optimized in the system; 3. The additive based on weathering continuous adjustment is improved by ball milling with carbon nanotube agent continuously adjusted by mullite in combination with weathering-resistant and adjustable liquid. At the same time, the carbon nanotube agent continuously adjusted by mullite is preheated by mullite, and then combined with flaky talc powder and sodium citrate solution for blending, and then further improved by carbon nanotube stirring. The carbon nanotubes with high specific surface area carry the mullite and talc powder system, optimizing the performance coordination and performance stability of the product. The weathering-resistant and adjustable liquid is heat-treated by nano mica powder to optimize its active efficiency, and then blended with sodium hexametaphosphate solution and nano calcium carbonate. Through the blending improvement between the carbon nanotube agent continuously adjusted by mullite and the weathering-resistant and adjustable liquid, the lamellar nano mica powder is interspersed in the system, and at the same time, the carbon nanotube agent continuously adjusted by mullite is blended. The raw materials cooperate with each other to synergistically enhance the performance of the reinforcing system, and thus the product performance is further improved; 4. The supplementary agent is treated with acid solution using silicon carbide to optimize its active efficiency, and then further optimized and blended with nano silica sol and sodium lignosulfonate solution to enhance the dispersion degree and active efficiency of silicon carbide. At the same time, it is further ultrasonically improved by the efficiency-adjusting and supplementary agent. The efficiency-adjusting and supplementary agent uses boron nitride fiber as the matrix, and then blends strontium titanate, zirconia, sodium silicate solution and sodium dodecylbenzenesulfonate solution. Through the blending and cooperation of the raw materials, the needle-like boron nitride fiber structure is used to reinforce the system. At the same time, through the blending and coordination of the raw materials, the synergistic effect between the prepared supplementary agent and the additive based on weathering continuous adjustment is further enhanced, thereby further improving the product performance. Specific embodiments

[0015] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0016] A preparation method of an elastic sandwich knitted fabric in this embodiment includes the following steps: Step 1: Select modified polyester filaments as raw materials. Three 25D modified polyester filaments are spun to form polyester 75D / FDY. Subsequently, polyester 75D / FDY is used as the raw material for the surface layer and the bottom layer, and 30D modified polyester filaments are used as the raw material for the intermediate layer; Step 2: Arrange the surface layer, the intermediate layer, and the bottom layer from top to bottom, and form a sandwich fabric body by integrally knitting with a knitting machine; Step 3: Perform overfeed treatment on the sandwich fabric body. The upper overfeed amount is 55%, and the lower overfeed amount is 15%. Finally, it is shaped at 180 °C for 30 s to obtain an elastic sandwich knitted fabric.

[0017] The preparation method of the modified polyester filaments in this embodiment is as follows: S01: Melting and co-mixing and extruding 85-90 parts of polyester resin, 9-11 parts of additives based on weather resistance continuous adjustment, and 5-8 parts of supplementary agents by weight. The extrusion temperature is 285-300 °C, and the extrusion pressure is 8 MPa to obtain polyester masterbatch; S02: Melting and spinning the polyester masterbatch and the toughening agent in a weight ratio of 5:1. After the spinning is completed, modified polyester filaments are obtained.

[0018] The spinning speed of the melt spinning treatment in this embodiment is 3000 m / min; the toughening agent is epoxy cyclohexyl polyether polyol.

[0019] The preparation method of the additives based on weather resistance continuous adjustment in this embodiment is as follows: S11: Preheat mullite at 55-60 °C for 1 h to obtain preheated mullite; mix 3-5 parts of preheated mullite, 2-4 parts of flaky talc powder, and 5-8 parts of a 8% sodium citrate solution by weight to obtain a mullite blending liquid; S12: Preparation of the weather resistance adjustment liquid: S12a: Heat-treat nano mica powder at 150-170 °C for 1 h, and then air-cool it to room temperature to obtain heat-improved nano mica powder; S12b: Mix 4-7 parts of heat-improved nano mica powder, 5-8 parts of sodium hexametaphosphate solution, and 2-4 parts of nano calcium carbonate by weight to obtain the weather resistance adjustment liquid; S13: immersing the carbon nanotubes in a mullite-adjusted solution with a weight of 3-5 times the total weight of the carbon nanotubes and stirring, filtering and drying after the stirring is completed to obtain a carbon nanotube agent mixed with mullite; S14: the carbon nanotube agent adjusted with mullite and the weather-resistant liquid are mixed in a weight ratio of 5:3 and ball-milled at a speed of 1500 r / min for 2 h. After the ball milling is completed, the mixture is filtered and dried to obtain an additive based on weather-resistant continuous adjustment.

[0020] The stirring speed of the stirring treatment in this embodiment is 350-400 r / min, and the stirring is for 2 hours; the mass fraction of the sodium hexametaphosphate solution is 5-8%.

[0021] The preparation method of the tonic agent of this embodiment is: S101: pretreating the silicon carbide with a sufficient amount of 8-10% by mass nitric acid solution for 1 hour at a treatment speed of 200 r / min. After the treatment, washing, filtering and drying are completed to obtain dry silicon carbide; 5-8 parts of dried silicon carbide, 1-2 parts of nano-silica sol and 6-10 parts of sodium lignin sulfonate solution are uniformly mixed by weight to obtain silicon carbide liquid; S102: subjecting silicon carbide liquid and the effect-adjusting and replenishing agent to ultrasonic treatment in a weight ratio of 5:3, filtering and drying after the treatment to obtain the effect-adjusting and replenishing agent.

[0022] The mass fraction of the sodium lignin sulfonate solution in this embodiment is 4-6%; the ultrasonic power of the ultrasonic treatment is 350-400W, and the ultrasonic treatment is performed for 1 hour.

[0023] The preparation method of the effect-regulating and replenishing agent of the present embodiment is: 5-8 parts of boron nitride fiber and 2-3 parts of strontium titanate are mixed and added into 6-10 parts of sodium dodecylbenzene sulfonate solution by weight, and then 1-2 parts of zirconium oxide and 2-4 parts of sodium silicate solution are added and mixed thoroughly, and finally filtered and dried to obtain an effect-regulating replenisher.

[0024] The mass fraction of the sodium dodecylbenzene sulfonate solution in this embodiment is 4-7%; the mass fraction of the sodium silicate solution is 2-5%.

[0025] The elastic sandwich knitted fabric is prepared by a method for preparing an elastic sandwich knitted fabric in this embodiment.

[0026] Embodiment 1: A method for preparing a stretch type sandwich knitted fabric, comprising the following steps: Step 1: Select modified polyester yarn as raw material, spin three 25D modified polyester yarns to form polyester 75D / FDY, then use polyester 75D / FDY as the raw material for the surface layer and the bottom layer, and use 30D modified polyester yarn as the raw material for the middle layer; Step 2: Arrange from top to bottom through the surface layer, middle layer and bottom layer, and form a sandwich fabric body by integrally knitting with a knitting machine; Step 3: Perform overfeeding treatment on the sandwich fabric body, with the upper overfeeding amount being 55% and the lower overfeeding amount being 15%. Finally, set the shape at 180°C for 30 s to obtain elastic sandwich knitted fabric.

[0027] The preparation method of the modified polyester filament in this embodiment is as follows: S01: Melting, blending and extruding 85 parts of polyester resin, 9 parts of additives based on weather resistance continuous adjustment, and 5 parts of supplementary agents by weight. The extrusion temperature is 285°C and the extrusion pressure is 8 MPa to obtain polyester masterbatch; S02: Melting and spinning the polyester masterbatch and the toughening agent according to a weight ratio of 5:1. After the spinning is completed, the modified polyester filament is obtained.

[0028] The spinning speed of the melt spinning treatment in this embodiment is 3000 m / min; the toughening agent is epoxy cyclohexyl polyether polyol.

[0029] The preparation method of the additives based on weather resistance continuous adjustment in this embodiment is as follows: S11: Preheat mullite at 55°C for 1 h to obtain preheated mullite; blend 3 parts of preheated mullite, 2 parts of flaky talc powder and 5 parts of 8% sodium citrate solution by weight to obtain a mullite blended solution; S12: Preparation of the weather resistance adjustment solution: S12a: Heat-treat nano mica powder at 150°C for 1 h, and then air-cool to room temperature to obtain heat-improved nano mica powder; S12b: Blend 4 parts of heat-improved nano mica powder, 5 parts of sodium hexametaphosphate solution and 2 parts of nano calcium carbonate by weight to obtain a weather resistance adjustment solution; S13: Immerse carbon nanotubes in 3 times the total weight of carbon nanotubes of the mullite blended solution for stirring treatment. After the stirring is completed, perform suction filtration and drying to obtain carbon nanotubes agent with mullite continuous adjustment; S14: Mix and ball-mill the carbon nanotubes agent with mullite continuous adjustment and the weather resistance adjustment solution according to a weight ratio of 5:3. The ball-milling speed is 1500 r / min and the ball-milling time is 2 h. After the ball-milling is completed, perform suction filtration and drying to obtain the additives based on weather resistance continuous adjustment.

[0030] The stirring speed of the stirring treatment in this embodiment is 350 / min and the stirring time is 2 h; the mass fraction of the sodium hexametaphosphate solution is 5%.

[0031] The preparation method of the supplementary agent in this embodiment is as follows: S101: Pretreat silicon carbide with a sufficient amount of 8% nitric acid solution for 1 h at a treatment rotation speed of 200 r / min. After the treatment, wash with water, filter by suction, and dry to obtain dried silicon carbide; Mix 5 parts of dried silicon carbide, 1 part of nano-silica sol, and 6 parts of sodium lignosulfonate solution evenly by weight to obtain silicon carbide liquid; S102: Ultrasonically treat the silicon carbide liquid and the calibration and supplement agent at a weight ratio of 5:3. After the treatment, filter by suction and dry to obtain the supplement agent.

[0032] In this example, the mass fraction of the sodium lignosulfonate solution is 4%; the ultrasonic power of the ultrasonic treatment is 350 W, and the ultrasonic treatment is carried out for 1 h.

[0033] The preparation method of the calibration and supplement agent in this example is as follows: Mix 5 parts of boron nitride fiber and 2 parts of strontium titanate by weight and add them to 6 parts of sodium dodecylbenzenesulfonate solution. Then add 1 part of zirconia and 2 parts of sodium silicate solution and mix and stir well. Finally, filter by suction and dry to obtain the calibration and supplement agent.

[0034] In this example, the mass fraction of the sodium dodecylbenzenesulfonate solution is 4%; the mass fraction of the sodium silicate solution is 2%.

[0035] The elastic sandwich knitted fabric prepared by the preparation method of the elastic sandwich knitted fabric in this example.

[0036] Example 2: A preparation method of an elastic sandwich knitted fabric, including the following steps: Step 1: Select modified polyester filaments as raw materials. Spin three 25D modified polyester filaments to form polyester 75D / FDY. Then use polyester 75D / FDY as the raw materials for the surface layer and the bottom layer, and 30D modified polyester filaments as the raw materials for the intermediate layer; Step 2: Arrange them in the order of the surface layer, the intermediate layer, and the bottom layer from top to bottom, and form a sandwich fabric body by integral knitting with a knitting machine; Step 3: Carry out overfeed treatment on the sandwich fabric body, with an upper overfeed amount of 55% and a lower overfeed amount of 15%. Finally, set the shape at 180 °C for 30 s to obtain the elastic sandwich knitted fabric.

[0037] The preparation method of the modified polyester filaments in this example is as follows: S01: Melt-blend and extrude 90 parts of polyester resin, 11 parts of additives based on weather resistance continuous adjustment, and 8 parts of the supplement agent by weight. The extrusion temperature is 300 °C, and the extrusion pressure is 8 MPa to obtain polyester masterbatch; S02: Carry out melt spinning treatment on the polyester masterbatch and the toughening agent at a weight ratio of 5:1. After the spinning, obtain the modified polyester filaments.

[0038] The spinning speed of the melt spinning process in this embodiment is 3000 m / min; the toughening agent is epoxy cyclohexyl polyether polyol.

[0039] The preparation method of the additive based on weather resistance continuous adjustment in this embodiment is as follows: S11: Preheat mullite at 60 °C for 1 h to obtain preheated mullite; mix 5 parts of preheated mullite, 4 parts of flaky talc powder and 8 parts of 8% sodium citrate solution by weight to obtain a mullite blending liquid. S12: Preparation of the weather resistance adjustment liquid: S12a: Heat-treat nano mica powder at 170 °C for 1 h, then air-cool to room temperature to obtain heat-improved nano mica powder. S12b: Mix 7 parts of heat-improved nano mica powder, 8 parts of sodium hexametaphosphate solution and 4 parts of nano calcium carbonate by weight to obtain a weather resistance adjustment liquid. S13: Immerse carbon nanotubes in 5 times the total weight of carbon nanotubes of the mullite blending liquid for stirring treatment. After stirring, filter and dry to obtain carbon nanotubes agent with mullite continuous adjustment. S14: Mix the carbon nanotubes agent with mullite continuous adjustment and the weather resistance adjustment liquid according to a weight ratio of 5:3, perform ball milling treatment at a ball milling speed of 1500 r / min for 2 h. After ball milling, filter and dry to obtain the additive based on weather resistance continuous adjustment.

[0040] The stirring speed of the stirring treatment in this embodiment is 400 r / min, and the stirring time is 2 h; the mass fraction of the sodium hexametaphosphate solution is 8%.

[0041] The preparation method of the supplementary agent in this embodiment is as follows: S101: Pretreat silicon carbide with 10% nitric acid solution in an amount sufficient for 1 h at a treatment speed of 200 r / min. After treatment, wash with water, filter and dry to obtain dry silicon carbide. Mix 8 parts of dry silicon carbide, 2 parts of nano silica sol and 10 parts of sodium lignosulfonate solution by weight to obtain a silicon carbide liquid. S102: Perform ultrasonic treatment on the silicon carbide liquid and the efficiency adjustment and supplement agent according to a weight ratio of 5:3. After treatment, filter and dry to obtain the supplementary agent.

[0042] The mass fraction of the sodium lignosulfonate solution in this embodiment is 6%; the ultrasonic power of the ultrasonic treatment is 400 W, and the ultrasonic treatment time is 1 h.

[0043] The preparation method of the efficiency adjustment and supplement agent in this embodiment is as follows: 8 parts of boron nitride fiber and 3 parts of strontium titanate were blended by weight and added to 10 parts of sodium dodecylbenzenesulfonate solution. Subsequently, 2 parts of zirconia and 4 parts of sodium silicate solution were added and blended and stirred thoroughly. Finally, filtration and drying were carried out to obtain the calibration improver.

[0044] In this example, the mass fraction of the sodium dodecylbenzenesulfonate solution is 7%; the mass fraction of the sodium silicate solution is 5%.

[0045] The elastic sandwich knitted fabric prepared by the preparation method of an elastic sandwich knitted fabric in this example.

[0046] Example 3: A preparation method of an elastic sandwich knitted fabric, comprising the following steps: Step 1: Modified polyester filaments were selected as raw materials. Three 25D modified polyester filaments were spun to form polyester 75D / FDY. Subsequently, polyester 75D / FDY was used as the raw material for the surface layer and the bottom layer, and 30D modified polyester filaments were used as the raw material for the intermediate layer; Step 2: It was arranged in the order of the surface layer, the intermediate layer and the bottom layer from top to bottom, and a sandwich fabric body was formed by integral knitting with a knitting machine; Step 3: The sandwich fabric body was subjected to overfeeding treatment. The upper overfeeding amount was 55%, and the lower overfeeding amount was 15%. Finally, it was shaped at 180 °C for 30 s to obtain the elastic sandwich knitted fabric.

[0047] The preparation method of the modified polyester filaments in this example is as follows: S01: 87.5 parts of polyester resin, 10 parts of an additive based on weather resistance continuous adjustment, and 6.5 parts of a supplementary agent were melt-blended and extruded by weight. The extrusion temperature was 290 °C, and the extrusion pressure was 8 MPa to obtain polyester masterbatch; S02: The polyester masterbatch and the toughening agent were melt-spun in a weight ratio of 5:1. After the spinning was completed, modified polyester filaments were obtained.

[0048] In this example, the spinning speed of the melt-spinning treatment was 3000 m / min; the toughening agent was epoxycyclohexyl polyether polyol.

[0049] The preparation method of the additive based on weather resistance continuous adjustment in this example is as follows: S11: Mullite was preheated at 57.5 °C for 1 h to obtain preheated mullite; 4 parts of preheated mullite, 3 parts of flaky talc powder and 6.5 parts of a 8% mass fraction sodium citrate solution were blended evenly by weight to obtain a mullite blending liquid; S12: Preparation of the weather resistance adjustment liquid: S12a: The nano mica powder was heat-treated at 160 °C for 1 h and then air-cooled to room temperature to obtain heat-improved nano mica powder; S12b: 5.5 parts of heat-modified nano-mica powder, 6.5 parts of sodium hexametaphosphate solution, and 3 parts of nano-calcium carbonate are uniformly mixed by weight to obtain a weather-resistant liquid; S13: immersing the carbon nanotubes in a mullite-adjusted solution with a weight of 4 times the total weight of the carbon nanotubes and stirring, filtering and drying after the stirring is completed to obtain a carbon nanotube agent mixed with mullite; S14: the carbon nanotube agent adjusted with mullite and the weather-resistant liquid are mixed in a weight ratio of 5:3 and ball-milled at a speed of 1500 r / min for 2 h. After the ball milling is completed, the mixture is filtered and dried to obtain an additive based on weather-resistant continuous adjustment.

[0050] The stirring speed of the stirring treatment in this embodiment is 370 r / min, and the stirring is for 2 hours; the mass fraction of the sodium hexametaphosphate solution is 6.5%.

[0051] The preparation method of the tonic agent of this embodiment is: S101: pretreating the silicon carbide with a sufficient amount of 9% by mass nitric acid solution for 1 hour at a treatment speed of 200 r / min. After the treatment, washing, filtering and drying are completed to obtain dry silicon carbide; 6.5 parts of dried silicon carbide, 1.5 parts of nano-silica sol and 8 parts of sodium lignin sulfonate solution were mixed uniformly by weight to obtain silicon carbide liquid; S102: subjecting silicon carbide liquid and the effect-adjusting and replenishing agent to ultrasonic treatment in a weight ratio of 5:3, filtering and drying after the treatment to obtain the effect-adjusting and replenishing agent.

[0052] The mass fraction of the sodium lignin sulfonate solution in this example is 5%; the ultrasonic power of the ultrasonic treatment is 375W, and the ultrasonic treatment is performed for 1 hour.

[0053] The preparation method of the effect-regulating and replenishing agent of the present embodiment is: 6.5 parts of boron nitride fiber and 2.5 parts of strontium titanate were mixed and added into 8 parts of sodium dodecylbenzene sulfonate solution by weight, and then 1.5 parts of zirconium oxide and 3 parts of sodium silicate solution were added and mixed thoroughly, and finally filtered and dried to obtain an effect-regulating replenisher.

[0054] The mass fraction of the sodium dodecylbenzene sulfonate solution in this embodiment is 5.5%; the mass fraction of the sodium silicate solution is 3.5%.

[0055] The elastic sandwich knitted fabric is prepared by a method for preparing an elastic sandwich knitted fabric in this embodiment.

[0056] Comparative Example 1: The difference from Example 3 is that no additive based on weathering adjustment is added.

[0057] Comparative Example 2: Example 3 is different in that mullite continuous adjustment carbon nanotube agent is not added in the preparation of the additive based on weather resistance continuous adjustment.

[0058] Comparative Example 3: Example 3 is different in that mullite blending liquid is not added in the preparation of the mullite continuous adjustment carbon nanotube agent.

[0059] Comparative Example 4: Example 3 is different in that mullite and flaky talc powder are not added in the mullite blending liquid.

[0060] Comparative Example 5: Example 3 is different in that carbon nanotubes are not added in the preparation of the mullite continuous adjustment carbon nanotube agent.

[0061] Comparative Example 6: Example 3 is different in that weather resistance adjustment liquid is not added in the preparation of the additive based on weather resistance continuous adjustment.

[0062] Comparative Example 7: Example 3 is different in that heat-improved nano mica powder and nano calcium carbonate are not added in the preparation of the weather resistance adjustment liquid.

[0063] Comparative Example 8: Example 3 is different in that a supplementary effect agent is not added.

[0064] Comparative Example 9: Example 3 is different in that silicon carbide liquid is not added in the preparation of the supplementary effect agent.

[0065] Comparative Example 10: Example 3 is different in that the effect adjustment and supplementing agent is not added in the preparation of the supplementary effect agent.

[0066] Comparative Example 11: Example 3 is different in that boron nitride fiber and strontium titanate are not added in the preparation of the effect adjustment and supplementing agent.

[0067] Comparative Example 12: Example 3 is different in that zirconia and sodium silicate solution are not added in the preparation of the effect adjustment and supplementing agent.

[0068] The products of Examples 1 - 3 and Comparative Examples 1 - 12 were subjected to tests on elasticity, heat preservation and bursting strength under normal conditions and weather resistance conditions. The weather resistance conditions were to irradiate the products at an ultraviolet intensity of 300 W / m 2 for 48 h, and the performance measurement results are shown in Table 1.

[0069] Table 1 Performance test results of the products of Examples 1 - 3 and Comparative Examples 1 - 12:

[0070] It can be concluded from Examples 1-3 and Comparative Examples 1-12 that the maximum elasticity of the product in Example 3 of the present invention can reach 23%, the heat retention rate can reach 95%, and the bursting strength can be as high as 804 N. The elasticity, heat retention, and bursting strength of the product can be improved in a coordinated manner, and the weather resistance stability effect of the product is remarkable; It can be seen from Comparative Example 1, Comparative Example 8, and Example 3 that when one of the additives based on weather resistance continuous adjustment and the supplementary agent is not added, the product performance deteriorates significantly. Only when the two are used in coordination and cooperate with each other, the product performance effect is the most significant; It can be seen from Comparative Examples 1-7 and Example 3 that mullite continuous adjustment carbon nanotube agent is not added in the preparation of the additive based on weather resistance continuous adjustment, mullite admixture liquid is not added in the preparation of the mullite continuous adjustment carbon nanotube agent, mullite and flaky talc powder are not added in the mullite admixture liquid, carbon nanotubes are not added in the preparation of the mullite continuous adjustment carbon nanotube agent, weather resistance adjustment liquid is not added in the preparation of the additive based on weather resistance continuous adjustment, and heat-improved nano mica powder and nano calcium carbonate are not added in the preparation of the weather resistance adjustment liquid. The performance of the product shows a deteriorating trend; The product performance effect is the most significant when the additive based on weather resistance continuous adjustment is made of the mullite continuous adjustment carbon nanotube agent obtained by the specific method of the present invention and the weather resistance adjustment liquid. Using other methods instead is not as obvious as the effect of the present invention. In addition, for the preparation of the weather resistance adjustment liquid and the mullite admixture liquid, the product effect is the most significant when made of the specific raw materials of the present invention. Using other methods is not as significant as the effect of the present invention; It can be seen from Comparative Examples 9-12 and Example 3 that silicon carbide liquid is not added in the preparation of the supplementary agent, effect adjustment supplementary agent is not added in the preparation of the supplementary agent, boron nitride fiber and strontium titanate are not added in the preparation of the effect adjustment supplementary agent, zirconia and sodium silicate solution are not added in the preparation of the effect adjustment supplementary agent. The performance of the product shows a deteriorating trend to varying degrees; The product performance effect is the most significant when the supplementary agent is made of the effect adjustment supplementary agent obtained by the specific method of the present invention and the silicon carbide liquid. In addition, the preparation of the effect adjustment supplementary agent has exclusivity. Using other methods instead is not as obvious as the solution of the present invention.

[0071] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention.

[0072] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only includes an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for preparing a stretch type sandwich knitted fabric, characterized in that: The following steps are involved: Step 1: Select modified polyester yarn as raw material, spin three 25D modified polyester yarns to form polyester 75D / FDY, then use polyester 75D / FDY as the raw material for the surface layer and the bottom layer, and use 30D modified polyester yarn as the raw material for the middle layer; The preparation method of the modified polyester yarn is: S01: 85-90 parts of polyester resin, 9-11 parts of weathering resistant continuous adjustment additives, and 5-8 parts of synergist are melt-blended and extruded at a temperature of 285-300° C. and a pressure of 8 MPa to obtain polyester masterbatch; S02: melt-spinning the polyester masterbatch and the toughening agent in a weight ratio of 5:1, and obtaining modified polyester yarn after the spinning is completed; Step 2: Arrange the surface layer, the middle layer and the bottom layer from top to bottom, and form a sandwich fabric body by weaving it in one piece using a weaving machine; Step 3: The sandwich fabric is overfed, with the upper overfeed amount being 55% and the lower overfeed amount being 15%. Finally, it is shaped at 180°C for 30s to obtain the elastic sandwich knitted fabric.

2. The method for preparing a stretch type sandwich knitted fabric according to claim 1, characterized in that: The spinning speed of the melt spinning process is 3000 m / min.

3. The method for preparing a stretch type sandwich knitted fabric according to claim 1, characterized in that: The toughening agent is epoxy cyclohexane polyether polyol.

4. The method for preparing a stretch type sandwich knitted fabric according to claim 1, characterized in that: The preparation method of the additive based on weathering continuous adjustment is: S11: preheating mullite at 55-60° C. for 1 hour to obtain preheated mullite; uniformly blending 3-5 parts of the preheated mullite, 2-4 parts of flaky talcum powder and 5-8 parts of 8% sodium citrate solution by weight to obtain a mullite blending solution; S12: Preparation of weather-resistant liquid: S12a: heat treating the nano-mica powder at 150-170° C. for 1 h, and then air-cooling to room temperature to obtain thermally improved nano-mica powder; S12b: 4-7 parts of heat-modified nano-mica powder, 5-8 parts of sodium hexametaphosphate solution, and 2-4 parts of nano-calcium carbonate are uniformly mixed by weight to obtain a weather-resistant liquid; S13: immersing the carbon nanotubes in a mullite-adjusted solution with a weight of 3-5 times the total weight of the carbon nanotubes and stirring, filtering and drying after the stirring is completed to obtain a carbon nanotube agent mixed with mullite; S14: the carbon nanotube agent adjusted with mullite and the weather-resistant liquid are mixed in a weight ratio of 5:3 and ball-milled at a speed of 1500 r / min for 2 h. After the ball milling is completed, the mixture is filtered and dried to obtain an additive based on weather-resistant continuous adjustment.

5. The method for preparing a stretch type sandwich knitted fabric according to claim 4, characterized in that: The stirring speed of the stirring treatment is 350-400 r / min, and the stirring is for 2 hours; the mass fraction of the sodium hexametaphosphate solution is 5-8%.

6. The method for preparing a stretch type sandwich knitted fabric according to claim 4, characterized in that: The preparation method of the tonic is as follows: S101: pretreating the silicon carbide with a sufficient amount of 8-10% by mass nitric acid solution for 1 hour at a treatment speed of 200 r / min. After the treatment, washing, filtering and drying are completed to obtain dry silicon carbide; 5-8 parts of dried silicon carbide, 1-2 parts of nano-silica sol and 6-10 parts of sodium lignin sulfonate solution are uniformly mixed by weight to obtain silicon carbide liquid; S102: subjecting silicon carbide liquid and the effect-adjusting and replenishing agent to ultrasonic treatment in a weight ratio of 5:3, filtering and drying after the treatment to obtain the effect-adjusting and replenishing agent.

7. The method for preparing a stretch type sandwich knitted fabric according to claim 6, characterized in that: The mass fraction of the sodium lignin sulfonate solution is 4-6%; the ultrasonic power of the ultrasonic treatment is 350-400W, and the ultrasonic treatment is performed for 1 hour.

8. The method for preparing a stretch type sandwich knitted fabric according to claim 6, characterized in that: The preparation method of the effect-regulating and replenishing agent is as follows: 5-8 parts of boron nitride fiber and 2-3 parts of strontium titanate are mixed and added into 6-10 parts of sodium dodecylbenzene sulfonate solution by weight, and then 1-2 parts of zirconium oxide and 2-4 parts of sodium silicate solution are added and mixed thoroughly, and finally filtered and dried to obtain an effect-regulating replenisher.

9. The method for preparing a stretch type sandwich knitted fabric according to claim 8, characterized in that: The mass fraction of the sodium dodecylbenzene sulfonate solution is 4-7%; the mass fraction of the sodium silicate solution is 2-5%.

10. A stretch type sandwich knitted fabric, prepared by the method for preparing a stretch type sandwich knitted fabric according to any one of claims 1 to 9.

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