Preparation method of a tent fabric with moisture permeability, heat insulation and ultraviolet resistance

Abstract

The present application belongs to the technical field of tent fabric, and relates to a preparation method of a moisture-permeable, heat-insulating and ultraviolet-resistant tent fabric. The moisture-permeable, heat-insulating and ultraviolet-resistant tent fabric is prepared by first performing bottom layer gluing on a polyester filament tent base cloth and drying, and then performing surface layer gluing on the surface of the bottom layer gluing and drying. The coating agent I used for the bottom layer gluing is obtained by uniformly mixing polyurethane emulsion I, triethylenediamine, aluminum oxide powder and tributyl phosphate, and then ultrasonic defoaming. The coating agent II used for the surface layer gluing is obtained by uniformly mixing polyurethane emulsion II, methyl ethyl ketone, N,N-dimethylformamide and rutile type nano titanium dioxide, and then ultrasonic defoaming. The synthesis method of the polyurethane emulsion II is as follows: first, vanillin is added to the polyurethane prepolymer, and then stirred and reacted; after that, mustard alcohol is added at a temperature of 60-75 DEG C, and then stirred and reacted; after that, the temperature is lowered, and deionized water is added, so as to obtain the polyurethane emulsion II. The tent fabric prepared by the method has good light-shielding, moisture-permeable and heat-insulating properties.

Description

Technical Field

[0001] This invention belongs to the field of tent fabric technology and relates to a method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric. Background Technology

[0002] With social development and the continuous improvement of people's living standards, outdoor living experiences have become an important part of life. Tourist tents are increasingly used by the general public and are also the best-selling type of tent on the market. For ease of carrying and transport, tent fabrics are relatively thin. Currently, lightweight tent products use low-denier polyester spun fabrics, such as 15D and 20D filaments, and are coated internally with PVC, PU, ​​or other silver-coated materials. However, in summer, a large amount of radiant heat from sunlight can still enter the tent, causing the internal temperature to rise continuously, resulting in excessive heat and inconvenience for people's outdoor activities.

[0003] Existing technologies include double-layer tents designed to achieve heat insulation, but this does not meet the requirement of lightweight tents. Many existing technologies also add pigments or increase the thickness and number of coatings to block light and insulate heat. Pigments themselves have a light-blocking effect, but their heat insulation effect is limited and needs to work in synergy with other components. Increasing the coating thickness will increase the weight and rigidity of the coating, which goes against the requirements of lightweight and durable tents.

[0004] In China, PVC coatings are widely used in research on waterproofing and breathability of tent fabrics. While they offer good waterproofing, they have poor breathability and are not resistant to low temperatures. Currently, polyurethane coatings are the ideal choice for tent fabrics. They are characterized by good elasticity, abrasion resistance, high temperature resistance, and good flexural strength. They are also suitable for thin coatings and high-pressure-resistance coatings, and most tent fabrics now use polyurethane coatings. Tent fabrics with ordinary polyurethane coatings have excellent waterproofing, but their breathability is significantly insufficient, leading to a noticeable stuffiness inside the tent.

[0005] Patent application CN101886340A discloses a highly waterproof, highly breathable, and flame-retardant coated fabric and its production method. The fabric comprises a base fabric and a highly waterproof, highly breathable, and flame-retardant coating layer, which is a non-porous polyurethane layer. The flame retardant used in this coating layer is a halogen-free particulate flame retardant. The production method involves uniformly coating the base fabric with a fabric coating slurry composed of a mixture of hydrophilic polyurethane resin, organic solvent, additives, and flame retardant. After drying, a highly waterproof, highly breathable, and flame-retardant coated product containing a hydrophilic flame-retardant polyurethane non-porous layer is obtained. Although this technique can impart high waterproofness and breathability to the fabric, it uses a coating slurry to uniformly coat the base fabric surface using a dry coating method. The amount of slurry required for fabrics of different thicknesses is uncertain, and it is also difficult to achieve precise seam sealing at the joints of tent fabrics. Therefore, fabrics prepared using this technique are not suitable for tent manufacturing.

[0006] Patent application CN217293824U discloses a method for preparing a composite phase change thermal insulation fabric by filling aerogel between a regular fabric and a fabric treated with a phase change material. The fabric prepared by the above method has a good thermal insulation effect. However, this kind of fabric that achieves thermal insulation by designing a double-layer fabric cannot meet the requirements of lightweight tents, and is prone to aerogel shedding and dusting, which affects the health of users.

[0007] Chinese patent CN112553914A discloses a method for preparing a waterproof and heat-insulating coating agent. It involves dispersing hydrophobic SiO2 aerogel in a polyvinylidene fluoride-hexafluoropropylene / solvent / water system. The micro-nano composite micropores formed by the separation of PVDF-HFP / hydrophobic SiO2 aerogel particles in the aqueous phase provide channels for moisture vapor released from the human body, giving it good moisture permeability. This method of creating pores through phase separation can solve the existing problems of air and moisture permeability. However, the dispersion of hydrophobic SiO2 aerogel in a solvent system can easily cause solvent molecules to enter the aerogel pores, damaging the nanoporous structure of the aerogel and affecting the heat insulation effect of the fabric.

[0008] Therefore, it is of great significance to study a method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric in order to solve the problems existing in the current technology. Summary of the Invention

[0009] The purpose of this invention is to solve the problems existing in the prior art and provide a method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric.

[0010] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0011] A method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric involves first applying a bottom layer of adhesive to a polyester filament tent base fabric and drying it, then applying a top layer of adhesive to the surface of the bottom layer and drying it to obtain the moisture-permeable, heat-insulating, and UV-resistant tent fabric.

[0012] The coating agent I used for the undercoat is obtained by uniformly mixing polyurethane emulsion I, triethylenediamine, alumina powder and tributyl phosphate, followed by ultrasonic defoaming. Triethylenediamine (catalyst) is commonly used in the polyurethane curing reaction. Alumina powder (filler) can improve the heat insulation effect and increase the coating hardness. Tributyl phosphate (defoamer) is commonly used to remove bubbles.

[0013] The coating agent II used in the surface coating is obtained by uniformly mixing polyurethane emulsion II, methyl ethyl ketone, N,N-dimethylformamide and rutile nano titanium dioxide, followed by ultrasonic defoaming; methyl ethyl ketone and N,N-dimethylformamide are solvents; rutile nano titanium dioxide is an anti-UV agent, which is superior to the common anatase titanium dioxide.

[0014] The synthesis method of polyurethane emulsion I is as follows: first, a polymerization reaction is carried out using polyether polyol and isocyanate as raw materials, and then the reaction product is dispersed in deionized water to obtain polyurethane emulsion I;

[0015] The synthesis method of polyurethane emulsion II is as follows: first, vanillin is added to the polyurethane prepolymer at a temperature of 35~45℃, and after stirring and reacting, mustard alcohol is added at a temperature of 60~75℃, and after stirring and reacting, the temperature is lowered and deionized water is added to obtain polyurethane emulsion II.

[0016] As a preferred technical solution:

[0017] The preparation method of the moisture-permeable, heat-insulating, and UV-resistant tent fabric described above includes the following specific steps:

[0018] (1) After mixing polyether polyol, isocyanate and dibutyltin dilaurate, the mixture is stirred at 60~80℃ for 1~3h to obtain polyurethane prepolymer I; the polyether polyol is preferably polytetrahydrofuran ether diol, and the isocyanate is preferably toluene diisocyanate. The initial viscosity of polytetrahydrofuran ether diol and toluene diisocyanate is low when reacting at 60~80℃. Dibutyltin dilaurate can accelerate the reaction as an efficient catalyst and complete the prepolymerization directly in the molten state without solvent dilution; although adding solvent can reduce the viscosity of the system, it will also increase VOC emissions and affect subsequent drying. Therefore, no solvent is added here in this invention.

[0019] (2) Add chain extender dimethylolpropionic acid to polyurethane prepolymer I and react at 70~90℃ for 2~4h; cool down to 40~60℃, add neutralizer triethylamine and continue to react for 1~4h to convert carboxyl groups into carboxylate salts and enhance water dispersibility; then add deionized water and emulsify and disperse under stirring at 2000~3500rpm to form polyurethane emulsion I;

[0020] (3) After mixing polyurethane emulsion I, triethylenediamine, alumina powder and tributyl phosphate evenly, stir at 200~300rpm for 1~3h, and then defoam by ultrasonication to obtain coating agent I;

[0021] (4) Place the polyether polyol in a reactor and dehydrate it in a vacuum at 100~120℃ for 1~3h; after the temperature drops to 70~85℃, add isocyanate, dibutyltin dilaurate and methyl ethyl ketone to the reactor and keep it warm for 2~5h to obtain polyurethane prepolymer II.

[0022] (5) In the system of step (4), after the temperature drops to 35~45℃, vanillin is added dropwise to the reaction vessel at a rate of 3~6mL / min. After the addition is completed, the reaction is stirred at 300~500rpm for 1~3h. After the temperature rises to 60~75℃, mustard alcohol is added dropwise to the reaction vessel at a rate of 3~6mL / min. After the addition is completed, the reaction is stirred at 400~600rpm for 2~4h. After the temperature drops to 40~50℃, deionized water is added to the reaction vessel and stirred at 300~600rpm for 1~3h to obtain polyurethane emulsion II.

[0023] (6) After mixing polyurethane emulsion II, methyl ethyl ketone, N,N-dimethylformamide and rutile nano titanium dioxide evenly, stir at 200~300rpm for 1~3h, and then defoam by ultrasonication to obtain coating agent II;

[0024] (7) First, coating agent I is applied to the polyester filament tent base fabric for the bottom layer and dried. Then, coating agent II is applied to the bottom layer surface and dried to obtain a moisture-permeable, heat-insulating and UV-resistant tent fabric.

[0025] The preparation method of the moisture-permeable, heat-insulating and UV-resistant tent fabric described above, in steps (1) to (3) by weight, is as follows: 50-60 parts of polyether polyol, 30-40 parts of isocyanate, 0.2-1 parts of dibutyltin dilaurate, 8-12 parts of dimethylolpropionic acid, 6-10 parts of triethylamine, 150-200 parts of deionized water, 1-4 parts of triethylenediamine, 15-20 parts of alumina powder, and 0.5-1.5 parts of tributyl phosphate.

[0026] In the preparation method of the moisture-permeable, heat-insulating and UV-resistant tent fabric described above, in steps (4) to (6) by weight, the polyether polyol is 51 to 58 parts, the isocyanate is 37 to 42 parts, the dibutyltin dilaurate is 0.5 to 1.5 parts, the butanone is 8 to 13 parts, the vanillin is 7 to 12 parts, the mustard is 15 to 22 parts, the deionized water is 120 to 160 parts, the methyl ethyl ketone is 15 to 20 parts, the N,N-dimethylformamide is 10 to 16 parts, and the rutile nano-titanium dioxide is 7 to 12 parts.

[0027] In the preparation method of the moisture-permeable, heat-insulating and UV-resistant tent fabric described above, the viscosity of polyurethane emulsion I in step (2) is 4000~5000mPa·s, and the viscosity of polyurethane emulsion II in step (5) is 6000~8000mPa·s.

[0028] In the preparation method of the moisture-permeable, heat-insulating and UV-resistant tent fabric described above, in step (7), the bottom layer is coated with adhesive by roller coating. After the bottom layer is coated with adhesive, a five-stage drying process is adopted. The drying temperatures of the first to fifth stages are 110~130℃, 130~140℃, 140~150℃, 150~160℃, and 130~140℃, respectively.

[0029] As described above, in the preparation method of a moisture-permeable, heat-insulating, and UV-resistant tent fabric, after the bottom layer is coated with adhesive and dried, the dry weight of the base fabric increases by 10-15 g / m². 2 The adhesive layer thickness is 0.15±0.02mm.

[0030] In the preparation method of the moisture-permeable, heat-insulating and UV-resistant tent fabric described above, the surface layer is coated with adhesive by roller coating in step (7), and a three-stage drying process is adopted after the surface layer is coated with adhesive. The drying temperatures of the first to third stages are 100~110℃, 130~140℃, and 150~170℃, respectively.

[0031] As described above, in the preparation method of a moisture-permeable, heat-insulating, and UV-resistant tent fabric, after the surface layer is coated with adhesive and dried, the dry weight of the fabric increases by 12-17 g / m². 2 The adhesive layer thickness is 0.15±0.02mm.

[0032] The method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric as described above results in a heat-blocking rate >45% and a moisture permeability >3000 g / (m²). 2 • 24h), UPF value > 300, T(UVA) AV / % < 2.5, UPF value decreases by ≤ 11% after 50 washes.

[0033] Invention principle:

[0034] When polyurethane prepolymer reacts with vanillin at 35-45℃, its phenolic hydroxyl groups form stable urethane bonds with isocyanate groups, constructing a three-dimensional network with high cross-linking density. When vanillin is used alone, although its phenolic hydroxyl groups can react with isocyanates to form urethane bonds, the methoxy groups on its benzene rings also create steric hindrance, reducing the actual reaction efficiency. Unreacted vanillin molecules can exist in the network through physical adsorption, becoming a source of migration to the coating surface. After the polyurethane prepolymer reacts with vanillin, adding mustard alcohol at 60-75℃ allows the allyl group of mustard alcohol to block free volume channels, significantly reducing the cross-sectional area of ​​the migration path. Simultaneously, the phenolic hydroxyl groups of mustard alcohol and the aldehyde groups of vanillin can form hydrogen bonds, significantly reducing molecular mobility (molecular mobility directly reflects the ability of molecules to undergo random thermal motion. Higher molecular mobility means more attempts to jump per unit time, a greater probability of successful jumps, a larger average displacement, and a faster diffusion rate). While vanillin's phenolic hydroxyl groups can capture water molecules through hydrogen bonds, the lack of a subsequent release mechanism causes adsorbed water molecules to remain for extended periods, forming localized concentration zones. This static adsorption not only fails to promote water molecule transport across the membrane but also blocks the original nanoscale free volume channels of the polyurethane membrane. When sinapol is added alone, its hydrophobic benzene ring and allyl alcohol chain lead to microphase separation imbalance, with hydrophobic regions agglomerating to form nanoscale "islands," blocking the continuous diffusion path of water vapor. However, when both are used together, a polar-hydrophobic nanogradient structure can be formed: vanillin statically adsorbs water molecules through its polar groups, while the aromatic ring of sinapol provides a diffusion springboard, forming a relay transport of "adsorption-diffusion-desorption." This nanoscale polar-hydrophobic continuous gradient structure not only solves the defects of using either alone (vanillin migration, sinapol islands) but also significantly improves the water vapor transport performance of the polyurethane membrane through the relay transport of "adsorption-diffusion-desorption." Furthermore, the vanillin phenolic hydroxyl groups absorb UVB (280~315nm), synergistically achieving UPF 300+ protection with rutile nano-titanium dioxide; the phonon coupling effect between alumina and rutile nano-titanium dioxide significantly improves near-infrared reflectivity (near-infrared bands account for about 50% of solar radiation energy and are the main reason for the heat absorption and temperature rise of objects. Improving near-infrared reflectivity can directly reduce the absorption of solar radiation heat, thereby reducing surface temperature and improving thermal insulation performance).

[0035] Beneficial effects:

[0036] (1) A method for preparing a breathable, heat-insulating, and UV-resistant tent fabric of the present invention involves adding vanillin and mustard alcohol sequentially to a polyurethane prepolymer. When the two coexist, a polar-hydrophobic nano-gradient structure can be formed. This nanoscale polar-hydrophobic continuous gradient structure not only solves the defects of using the two alone (vanillin migration, mustard alcohol islands), but also significantly improves the water vapor transport performance of the polyurethane membrane through "adsorption-diffusion-desorption" relay transmission.

[0037] (2) A method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric according to the present invention, wherein the tent fabric obtained has good light-blocking, moisture-permeable, and heat-insulating properties;

[0038] (3) The method for preparing a moisture-permeable, heat-insulating and UV-resistant tent fabric of the present invention uses only two coating layers, which reduces the process steps and the coating thickness is small, which meets the lightweight characteristics of tourist tents. Attached Figure Description

[0039] Figure 1 The image shows the infrared spectrum of polyurethane emulsion II from Example 1 after drying. Detailed Implementation

[0040] The present invention will be further described below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0041] The test methods involved in the performance indicators in the embodiments and comparative examples of this invention are as follows:

[0042] Heat shading rate: used to characterize thermal insulation performance, tested in accordance with GB / T 41560-2022.

[0043] Moisture permeability: Tested in accordance with GB / T 12704.1-2009.

[0044] UPF value, T(UVA) AV / %: Tested in accordance with GB / T 18830-2009.

[0045] UPF value decay after 50 washes: The fabric was first washed 50 times according to GB / T 8629-2017 standard (each cycle includes washing, rinsing and drying), and then the fabric's UV protection performance UPF value was immediately tested according to GB / T 18830-2009 standard and compared with the decay rate before washing.

[0046] Example 1

[0047] A method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric, comprising the following specific steps:

[0048] (1) By weight, 50 parts of polytetrahydrofuran ether diol (manufacturer: BASF, Germany, brand: PTHF1000), 30 parts of toluene-2,4-diisocyanate and 0.2 parts of dibutyltin dilaurate were mixed and stirred at 60°C for 1 h to obtain polyurethane prepolymer I;

[0049] (2) Add 8 parts of dimethylolpropionic acid to the polyurethane prepolymer I obtained in step (1) and react at 70°C for 2 hours; cool down to 40°C and add 6 parts of triethylamine to continue the reaction for 1 hour; then add 150 parts of deionized water and emulsify and disperse under stirring at 2000 rpm to form a polyurethane emulsion I with a viscosity of 4000 mPa·s.

[0050] (3) After mixing polyurethane emulsion I obtained in step (2), 1 part of triethylenediamine, 15 parts of alumina powder and 0.5 parts of tributyl phosphate evenly, stir at 200 rpm for 1 h, and then defoam by ultrasonication to obtain coating agent I.

[0051] (4) Place 51 parts of polytetrahydrofuran ether diol in a reactor and dehydrate it in a vacuum at 100°C for 1 hour; after the temperature drops to 70°C, add 37 parts of toluene-2,4-diisocyanate, 0.5 parts of dibutyltin dilaurate and 8 parts of butanone to the reactor and keep it at the temperature for 2 hours to obtain polyurethane prepolymer II.

[0052] (5) In the system of step (4), after the temperature drops to 35°C, 7 parts of vanillin are added dropwise to the reactor at a rate of 3 mL / min. After the addition is completed, the mixture is stirred at 300 rpm for 1 h. After the temperature rises to 60°C, 15 parts of mustard are added dropwise to the reactor at a rate of 3 mL / min. After the addition is completed, the mixture is stirred at 400 rpm for 2 h. After the temperature drops to 40°C, 120 parts of deionized water are added to the reactor and stirred at 300 rpm for 1 h to obtain polyurethane emulsion II with a viscosity of 6000 mPa·s.

[0053] like Figure 1 As shown, the characteristic peak of the isocyanate group (-NCO) is 2270~2240 cm⁻¹. -1 The near-complete disappearance within this range indicates that the -NCO groups in polyurethane prepolymer II react with the phenolic hydroxyl groups of vanillin / sinositol; 1725~1705cm -1 The strong and broad absorption peak is attributed to the carbonyl group of the newly formed carbamate bond (C=O stretching vibration), reflecting the hydrogen bonding effect in the cross-linked network; 1530~1520 cm⁻¹ -1 The presence of a distinct amide II band absorption peak confirms the presence of NH groups in the carbamate bond; 3200~3400 cm⁻¹ -1 The appearance of a broad and strong absorption band (OH stretching vibration region) includes contributions from the NH group of the carbamate bond and intermolecular hydrogen bonds formed between the vanillin aldehyde group and the phenolic hydroxyl group of the sinapone, leading to the widening of the peak bandwidth.

[0054] (6) After mixing polyurethane emulsion II obtained in step (5), 15 parts of methyl ethyl ketone, 10 parts of N,N-dimethylformamide and 7 parts of rutile nano titanium dioxide evenly, stir at 200 rpm for 3 hours, and then defoam by ultrasonication to obtain coating agent II.

[0055] (7) After applying coating agent I as the undercoat on the 75D polyester filament tent base fabric using a roller coating method, a five-stage drying process is adopted. The drying temperatures for the first to fifth stages are 110℃, 130℃, 140℃, 150℃, and 130℃, respectively. The production speed of the roller coating method is 25m / min. After the undercoat is applied and dried, the dry weight of the base fabric increases by 10g / m. 2 The adhesive layer thickness is 0.13mm;

[0056] (8) After applying coating agent II to the bottom coating surface in step (7) using a roller coating method, a three-stage drying process is adopted. The drying temperatures for the first to third stages are 100℃, 130℃, and 150℃, respectively. The production speed of the roller coating method is 25m / min. After drying, a moisture-permeable, heat-insulating, and UV-resistant tent fabric is obtained. After the top coating is applied and dried, the dry weight of the fabric increases by 12g / m². 2 The adhesive layer thickness is 0.13mm.

[0057] The final moisture-permeable, heat-insulating, and UV-resistant tent fabric has a heat-blocking rate of 46% and a moisture permeability of 3530 g / (m²). 2 •24h), UPF value is 310, T(UVA) AV The UPF value of the breathable, heat-insulating, and UV-resistant tent fabric decreased by 11% after 50 washes, with a percentage of 2.4%.

[0058] Comparative Example 1

[0059] A method for preparing an anti-ultraviolet tent fabric is basically the same as in Example 1, except that vanillin is omitted in step (5), and mustard is added directly.

[0060] The final UV-resistant tent fabric has a heat shielding rate of 36% and a moisture permeability of 2110 g / (m²). 2 •24h), UPF value is 210, T(UVA) AV The percentage is 6, and the UPF value decreases by 21% after 50 washes.

[0061] Comparing Comparative Example 1 and Example 1, it can be found that Comparative Example 1 exhibits decreased moisture permeability, heat shielding efficiency, and UPF value, and poor wash stability. This is because when sinapol is used alone, its hydrophobic benzene ring and allyl alcohol chain induce microphase separation, forming nanoscale hydrophobic "islands." These islands block the continuous diffusion path of water vapor, preventing the "adsorption-diffusion-desorption" relay transport provided by vanillin in Example 1. The polar groups (phenolic hydroxyl groups) of vanillin can statically adsorb water molecules, providing initial impetus for water vapor to cross the membrane, while sinapol acts as a diffusion springboard to promote desorption. In the absence of vanillin, water molecules cannot effectively adsorb and initiate the transport chain, resulting in reduced moisture permeability. The heat shielding efficiency mainly depends on near-infrared reflectivity. In Example 1, vanillin and rutile nano-titanium dioxide synergistically enhance UVB absorption. Comparative Example 1 lacks vanillin, and the phonon coupling effect of titanium dioxide alone is insufficient to efficiently reflect near-infrared rays, leading to reduced heat insulation efficiency. The phenolic hydroxyl groups of vanillin are key UVB absorbers, which can form synergistic protection with titanium dioxide. In Comparative Example 1, after omitting vanillin, the UPF value mainly relied on titanium dioxide absorption, but the lack of supplementary organic UV absorbers resulted in incomplete protection across the UV spectrum, especially with increased transmittance in the UVA region. Furthermore, when sinapol exists alone, it cannot stabilize unreacted molecules through hydrogen bonding, making it easier for sinapol molecules to be lost during washing, thus exacerbating the decline in UPF value.

[0062] Comparative Example 2

[0063] A method for preparing an anti-ultraviolet tent fabric is basically the same as in Example 1, except that in step (5), mustard is omitted and only vanillin is added.

[0064] The final UV-resistant tent fabric has a heat shielding rate of 40% and a moisture permeability of 2240 g / (m²). 2 • 24h), UPF value is 230, T(UVA) AV The percentage is 4.5; the UPF value decreases by 25% after 50 washes.

[0065] Comparing Comparative Example 2 and Example 1, it can be observed that the moisture permeability and heat shielding rate of Comparative Example 2 decreased, and the UPF degradation was accelerated after washing. This is because when vanillin is used alone, the methoxy group on its benzene ring creates steric hindrance, reducing the reaction efficiency with isocyanate. Some unreacted vanillin molecules exist in the network through physical adsorption. These free molecules easily migrate to the coating surface, blocking the nanoscale free volume channels of polyurethane. At the same time, although the phenolic hydroxyl groups of vanillin can adsorb water molecules, they lack the "diffusion springboard" provided by mustard alcohol, and cannot achieve the relay transport of "adsorption-diffusion-desorption". The adsorbed water molecules remain for a long time, forming local high concentration areas, statically blocking the channels, resulting in a decrease in moisture permeability; the unreacted vanillin molecules are not stabilized by hydrogen bonds with mustard alcohol, and are easily dissolved by water during washing. High molecular activity leads to accelerated diffusion rate and rapid degradation of the UPF protective layer. Due to the lack of the "blocking of free volume channels" mechanism of myrosinol, the migration path is not interrupted, and the degradation is significant after 50 washes. The heat-shielding rate depends on near-infrared reflection. The lack of vanillin has little effect on titanium dioxide coupling, but the decrease in moisture permeability leads to the accumulation of moisture inside the fabric, which indirectly weakens the heat insulation effect.

[0066] Example 2

[0067] A method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric, comprising the following specific steps:

[0068] (1) By weight, 52 parts of polytetrahydrofuran ether diol (manufacturer: BASF, Germany, brand: PTHF1000), 33 parts of toluene-2,4-diisocyanate and 0.4 parts of dibutyltin dilaurate were mixed and stirred at 65°C for 1.5 h to obtain polyurethane prepolymer I;

[0069] (2) Add 9 parts of dimethylolpropionic acid to the polyurethane prepolymer I obtained in step (1) and react at 75°C for 2.5 h; cool down to 45°C and add 7 parts of triethylamine to continue the reaction for 2 h; then add 160 parts of deionized water and emulsify and disperse under stirring at 2500 rpm to form polyurethane emulsion I with a viscosity of 4200 mPa·s.

[0070] (3) After mixing polyurethane emulsion I obtained in step (2), 2 parts of triethylenediamine, 16 parts of alumina powder and 0.8 parts of tributyl phosphate evenly, stir at 225 rpm for 2 hours, and then defoam by ultrasonication to obtain coating agent I.

[0071] (4) Place 53 parts of polytetrahydrofuran ether diol in a reactor and dehydrate it in a vacuum at 105°C for 2 hours; after the temperature drops to 75°C, add 38 parts of toluene-2,4-diisocyanate, 0.8 parts of dibutyltin dilaurate and 9 parts of butanone to the reactor and keep it at the temperature for 2.5 hours to obtain polyurethane prepolymer II.

[0072] (5) In the system of step (4), after the temperature drops to 38°C, 8 parts of vanillin are added dropwise to the reactor at a rate of 3.5 mL / min. After the addition is completed, the mixture is stirred at 350 rpm for 2 h. After the temperature rises to 65°C, 16 parts of mustard are added dropwise to the reactor at a rate of 4 mL / min. After the addition is completed, the mixture is stirred at 450 rpm for 2.5 h. After the temperature drops to 42°C, 130 parts of deionized water are added to the reactor and stirred at 350 rpm for 2 h to obtain polyurethane emulsion II with a viscosity of 6500 mPa·s.

[0073] (6) After mixing polyurethane emulsion II obtained in step (5), 16 parts of methyl ethyl ketone, 12 parts of N,N-dimethylformamide and 8 parts of rutile nano titanium dioxide evenly, stir at 225 rpm for 2.5 h, and then defoam by ultrasonication to obtain coating agent II.

[0074] (7) After applying coating agent I as a base coat to the 75D polyester filament tent base fabric using a roller coating method, a five-stage drying process is adopted. The drying temperatures for the first to fifth stages are 115℃, 132℃, 142℃, 152℃, and 132℃, respectively. The production speed of the roller coating method is 27m / min. After the base coat is applied and dried, the dry weight of the base fabric increases by 11g / m. 2 The adhesive layer thickness is 0.15mm;

[0075] (8) After applying coating agent II to the bottom coating surface in step (7) using a roller coating method, a three-stage drying process is adopted. The drying temperatures for the first to third stages are 103℃, 133℃, and 155℃, respectively. The production speed of the roller coating method is 27m / min. After drying, a moisture-permeable, heat-insulating, and UV-resistant tent fabric is obtained. After the top coating and drying, the dry weight of the fabric increases by 13g / m². 2 The adhesive layer thickness is 0.15mm.

[0076] The final moisture-permeable, heat-insulating, and UV-resistant tent fabric has a heat-blocking rate of 47% and a moisture permeability of 3590 g / (m²). 2 •24h), UPF value is 312, T(UVA) AV The UPF value of the breathable, heat-insulating, and UV-resistant tent fabric decreases by 10% after 50 washes, with a percentage of 2.3%.

[0077] Example 3

[0078] A method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric, comprising the following specific steps:

[0079] (1) By weight, 55 parts of polytetrahydrofuran ether diol (manufacturer: BASF, Germany, brand: PTHF1000), 35 parts of toluene-2,4-diisocyanate and 0.5 parts of dibutyltin dilaurate were mixed and stirred at 70°C for 2 hours to obtain polyurethane prepolymer I.

[0080] (2) Add 10 parts of dimethylolpropionic acid to the polyurethane prepolymer I obtained in step (1) and react at 80°C for 3 hours; cool down to 50°C and add 8 parts of triethylamine to continue the reaction for 3 hours; then add 170 parts of deionized water and emulsify and disperse under stirring at 3000 rpm to form polyurethane emulsion I with a viscosity of 4400 mPa·s.

[0081] (3) After mixing polyurethane emulsion I obtained in step (2), 3 parts of triethylenediamine, 17 parts of alumina powder and 1 part of tributyl phosphate evenly, stir at 250 rpm for 2.5 h, and then defoam by ultrasonication to obtain coating agent I.

[0082] (4) Place 55 parts of polytetrahydrofuran ether diol in a reactor and dehydrate it in a vacuum at 110°C for 2.5 h; after the temperature drops to 80°C, add 39 parts of toluene-2,4-diisocyanate, 1 part of dibutyltin dilaurate and 11 parts of butanone to the reactor and keep it at the temperature for 3 h to obtain polyurethane prepolymer II.

[0083] (5) In the system of step (4), after the temperature drops to 40℃, 10 parts of vanillin are added dropwise to the reactor at a rate of 4 mL / min. After the addition is completed, the mixture is stirred at 400 rpm for 2.5 h. After the temperature rises to 70℃, 18 parts of mustard are added dropwise to the reactor at a rate of 4 mL / min. After the addition is completed, the mixture is stirred at 500 rpm for 3 h. After the temperature drops to 45℃, 140 parts of deionized water are added to the reactor and stirred at 400 rpm for 2 h to obtain polyurethane emulsion II with a viscosity of 7100 mPa·s.

[0084] (6) After mixing polyurethane emulsion II obtained in step (5), 17 parts of methyl ethyl ketone, 14 parts of N,N-dimethylformamide and 9 parts of rutile nano titanium dioxide evenly, stir at 250 rpm for 2 h, and then defoam by ultrasonication to obtain coating agent II.

[0085] (7) After applying coating agent I as a base coat to the 75D polyester filament tent base fabric using a roller coating method, a five-stage drying process is adopted. The drying temperatures for the first to fifth stages are 120℃, 135℃, 145℃, 155℃, and 135℃, respectively. The roller coating production speed is 30m / min. After the base coat is applied and dried, the dry weight of the base fabric increases by 13g / m. 2 The adhesive layer thickness is 0.15mm;

[0086] (8) After applying coating agent II to the bottom coating surface in step (7) using a roller coating method, a three-stage drying process is adopted. The drying temperatures for the first to third stages are 105℃, 135℃, and 160℃, respectively. The roller coating production speed is 30m / min. After drying, a moisture-permeable, heat-insulating, and UV-resistant tent fabric is obtained. After the top coating and drying, the dry weight of the fabric increases by 15g / m². 2The adhesive layer thickness is 0.15mm.

[0087] The final moisture-permeable, heat-insulating, and UV-resistant tent fabric has a heat-blocking rate of 47% and a moisture permeability of 3630 g / (m²). 2 • 24h), UPF value 315, T(UVA) AV The UPF value of the breathable, heat-insulating, and UV-resistant tent fabric is 2.2%, and the UPF value decreases by 10% after 50 washes.

[0088] Example 4

[0089] A method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric, comprising the following specific steps:

[0090] (1) By weight, 57 parts of polytetrahydrofuran ether diol (manufacturer: BASF, Germany, brand: PTHF1000), 38 parts of toluene-2,4-diisocyanate and 0.7 parts of dibutyltin dilaurate were mixed and stirred at 75°C for 2.5 h to obtain polyurethane prepolymer I;

[0091] (2) Add 11 parts of dimethylolpropionic acid to the polyurethane prepolymer I obtained in step (1) and react at 85°C for 3.5 h; cool down to 55°C and add 9 parts of triethylamine to continue the reaction for 3 h; then add 190 parts of deionized water and emulsify and disperse under stirring at 3200 rpm to form polyurethane emulsion I with a viscosity of 4700 mPa·s.

[0092] (3) After mixing polyurethane emulsion I obtained in step (2), 3 parts of triethylenediamine, 19 parts of alumina powder and 1.2 parts of tributyl phosphate evenly, stir at 275 rpm for 3 hours, and then defoam by ultrasonication to obtain coating agent I.

[0093] (4) Place 57 parts of polytetrahydrofuran ether diol in a reactor and dehydrate it in a vacuum at 115°C for 3 hours; after the temperature drops to 82°C, add 40 parts of toluene-2,4-diisocyanate, 1.3 parts of dibutyltin dilaurate and 12 parts of butanone to the reactor and keep it at the temperature for 4 hours to obtain polyurethane prepolymer II.

[0094] (5) In the system of step (4), after the temperature drops to 42℃, 11 parts of vanillin are added dropwise to the reactor at a rate of 5 mL / min. After the addition is completed, the mixture is stirred at 450 rpm for 2.5 h. After the temperature rises to 72℃, 20 parts of mustard alcohol are added dropwise to the reactor at a rate of 5 mL / min. After the addition is completed, the mixture is stirred at 550 rpm for 3.5 h. After the temperature drops to 48℃, 150 parts of deionized water are added to the reactor and stirred at 500 rpm for 3 h to obtain polyurethane emulsion II with a viscosity of 7600 mPa·s.

[0095] (6) After mixing polyurethane emulsion II obtained in step (5), 19 parts of methyl ethyl ketone, 15 parts of N,N-dimethylformamide and 11 parts of rutile nano titanium dioxide evenly, stir at 275 rpm for 1.5 h, and then defoam by ultrasonication to obtain coating agent II.

[0096] (7) After applying coating agent I as a base coat to the 75D polyester filament tent base fabric using a roller coating method, a five-stage drying process is adopted. The drying temperatures for the first to fifth stages are 125℃, 138℃, 148℃, 158℃, and 138℃, respectively. The production speed of the roller coating method is 32m / min. After the base coat is applied and dried, the dry weight of the base fabric increases by 14g / m. 2 The adhesive layer thickness is 0.16mm;

[0097] (8) After applying coating agent II to the bottom coating surface in step (7) using a roller coating method, a three-stage drying process is adopted. The drying temperatures for the first to third stages are 108℃, 138℃, and 165℃, respectively. The roller coating production speed is 32m / min. After drying, a moisture-permeable, heat-insulating, and UV-resistant tent fabric is obtained. After the top coating and drying, the dry weight of the fabric increases by 16g / m². 2 The adhesive layer thickness is 0.16mm.

[0098] The final moisture-permeable, heat-insulating, and UV-resistant tent fabric has a heat-blocking rate of 48% and a moisture permeability of 3680 g / (m²). 2 • 24h), UPF value 318, T(UVA) AV The UPF value of the breathable, heat-insulating, and UV-resistant tent fabric decreased by 9% after 50 washes, with a percentage of 2.2%.

[0099] Example 5

[0100] A method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric, comprising the following specific steps:

[0101] (1) By weight, 60 parts of polytetrahydrofuran ether diol (manufacturer: BASF, Germany, brand: PTHF1000), 40 parts of toluene-2,4-diisocyanate and 1 part of dibutyltin dilaurate were mixed and stirred at 80°C for 3 hours to obtain polyurethane prepolymer I.

[0102] (2) Add 12 parts of dimethylolpropionic acid to the polyurethane prepolymer I obtained in step (1) and react at 90°C for 4 hours; cool down to 60°C and add 10 parts of triethylamine to continue the reaction for 4 hours; then add 200 parts of deionized water and emulsify and disperse under stirring at 3500 rpm to form a polyurethane emulsion I with a viscosity of 5000 mPa·s.

[0103] (3) After mixing polyurethane emulsion I obtained in step (2), 4 parts of triethylenediamine, 20 parts of alumina powder and 1.5 parts of tributyl phosphate evenly, stir at 300 rpm for 3 hours, and then defoam by ultrasonication to obtain coating agent I.

[0104] (4) Place 58 parts of polytetrahydrofuran ether diol in a reactor and dehydrate it in a vacuum at 120°C for 3 hours; after the temperature drops to 85°C, add 42 parts of toluene-2,4-diisocyanate, 1.5 parts of dibutyltin dilaurate and 13 parts of butanone to the reactor and keep it at the temperature for 5 hours to obtain polyurethane prepolymer II.

[0105] (5) In the system of step (4), after the temperature drops to 45℃, 12 parts of vanillin are added dropwise to the reactor at a rate of 6 mL / min. After the addition is completed, the mixture is stirred at 500 rpm for 3 h. After the temperature rises to 75℃, 22 parts of mustard alcohol are added dropwise to the reactor at a rate of 6 mL / min. After the addition is completed, the mixture is stirred at 600 rpm for 4 h. After the temperature drops to 50℃, 160 parts of deionized water are added to the reactor and stirred at 600 rpm for 3 h to obtain polyurethane emulsion II with a viscosity of 8000 mPa·s.

[0106] (6) After mixing the polyurethane emulsion II obtained in step (5), 20 parts of methyl ethyl ketone, 16 parts of N,N-dimethylformamide and 12 parts of rutile nano titanium dioxide evenly, stir at 300 rpm for 1 h, and then defoam by ultrasonication to obtain coating agent II.

[0107] (7) After applying coating agent I as a base coat to the 75D polyester filament tent base fabric using a roller coating method, a five-stage drying process is adopted. The drying temperatures for the first to fifth stages are 130℃, 140℃, 150℃, 160℃, and 140℃, respectively. The production speed of the roller coating method is 35m / min. After the base coat is applied and dried, the dry weight of the base fabric increases by 15g / m. 2 The adhesive layer thickness is 0.17mm;

[0108] (8) After applying coating agent II to the bottom coating surface in step (7) using a roller coating method, a three-stage drying process is adopted. The drying temperatures for the first to third stages are 110℃, 140℃, and 170℃, respectively. The roller coating production speed is 35m / min. After drying, a moisture-permeable, heat-insulating, and UV-resistant tent fabric is obtained. After the top coating and drying, the dry weight of the fabric increases by 17g / m². 2 The adhesive layer thickness is 0.17mm.

[0109] The final moisture-permeable, heat-insulating, and UV-resistant tent fabric has a heat-blocking rate of 48% and a moisture permeability of 3720 g / (m²). 2 • 24h), UPF value 320, T(UVA) AV The UPF value of the breathable, heat-insulating, and UV-resistant tent fabric decreased by 9% after 50 washes, with a UPF value of 2.1%.

Claims

1. A method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric, characterized in that: A moisture-permeable, heat-insulating, and UV-resistant tent fabric is made by first applying a bottom layer of adhesive to the polyester filament tent base fabric and drying it, and then applying a top layer of adhesive to the bottom layer and drying it. The coating agent I used for the bottom layer adhesive is obtained by uniformly mixing polyurethane emulsion I, triethylenediamine, alumina powder and tributyl phosphate, and then ultrasonically defoaming. The coating agent II used for the surface coating is obtained by uniformly mixing polyurethane emulsion II, methyl ethyl ketone, N,N-dimethylformamide and rutile nano titanium dioxide, followed by ultrasonic defoaming. The synthesis method of polyurethane emulsion I is as follows: first, a polymerization reaction is carried out using polyether polyol and isocyanate as raw materials, and then the reaction product is dispersed in deionized water to obtain polyurethane emulsion I; The synthesis method of polyurethane emulsion II is as follows: first, vanillin is added to polyurethane prepolymer at a temperature of 35~45℃, and after stirring and reacting, mustard alcohol is added at a temperature of 60~75℃, and after stirring and reacting, the temperature is lowered and deionized water is added to obtain polyurethane emulsion II. The viscosity of polyurethane emulsion I is 4000~5000 mPa·s, and the viscosity of polyurethane emulsion II is 6000~8000 mPa·s.

2. The method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric according to claim 1, characterized in that, The specific steps are as follows: (1) After mixing polyether polyol, isocyanate and dibutyltin dilaurate, stir and react at 60~80℃ for 1~3h to obtain polyurethane prepolymer I; (2) Add dimethylolpropionic acid to polyurethane prepolymer I and react at 70~90℃ for 2~4h; cool down to 40~60℃ and add triethylamine to continue the reaction for 1~4h; then add deionized water and emulsify and disperse under stirring at 2000~3500rpm to form polyurethane emulsion I. (3) After mixing polyurethane emulsion I, triethylenediamine, alumina powder and tributyl phosphate evenly, stir at 200~300rpm for 1~3h, and then defoam by ultrasonication to obtain coating agent I; (4) Place the polyether polyol in a reactor and dehydrate it in a vacuum at 100~120℃ for 1~3h; after the temperature drops to 70~85℃, add isocyanate, dibutyltin dilaurate and methyl ethyl ketone to the reactor and keep it warm for 2~5h to obtain polyurethane prepolymer II. (5) In the system of step (4), after the temperature drops to 35~45℃, vanillin is added dropwise to the reaction vessel at a rate of 3~6mL / min. After the addition is completed, the reaction is stirred at 300~500rpm for 1~3h. After the temperature rises to 60~75℃, mustard alcohol is added dropwise to the reaction vessel at a rate of 3~6mL / min. After the addition is completed, the reaction is stirred at 400~600rpm for 2~4h. After the temperature drops to 40~50℃, deionized water is added to the reaction vessel and stirred at 300~600rpm for 1~3h to obtain polyurethane emulsion II. (6) After mixing polyurethane emulsion II, methyl ethyl ketone, N,N-dimethylformamide and rutile nano titanium dioxide evenly, stir at 200~300rpm for 1~3h, and then defoam by ultrasonication to obtain coating agent II; (7) First, coating agent I is applied to the polyester filament tent base fabric for the bottom layer and dried. Then, coating agent II is applied to the bottom layer surface and dried to obtain a moisture-permeable, heat-insulating and UV-resistant tent fabric.

3. The method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric according to claim 2, characterized in that, By weight, in steps (1) to (3), the polyether polyol is 50 to 60 parts, the isocyanate is 30 to 40 parts, the dibutyltin dilaurate is 0.2 to 1 part, the dimethylolpropionic acid is 8 to 12 parts, the triethylamine is 6 to 10 parts, the deionized water is 150 to 200 parts, the triethylenediamine is 1 to 4 parts, the alumina powder is 15 to 20 parts, and the tributyl phosphate is 0.5 to 1.5 parts.

4. The method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric according to claim 2, characterized in that, By weight, in steps (4) to (6), the polyether polyol is 51 to 58 parts, the isocyanate is 37 to 42 parts, the dibutyltin dilaurate is 0.5 to 1.5 parts, the butanone is 8 to 13 parts, the vanillin is 7 to 12 parts, the myrosinol is 15 to 22 parts, the deionized water is 120 to 160 parts, the methyl ethyl ketone is 15 to 20 parts, the N,N-dimethylformamide is 10 to 16 parts, and the rutile nano-titanium dioxide is 7 to 12 parts.

5. The method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric according to claim 2, characterized in that, In step (7), the bottom layer adhesive is applied by roller coating. After the bottom layer adhesive is applied, a five-stage drying process is adopted. The drying temperatures of the first to fifth stages are 110~130℃, 130~140℃, 140~150℃, 150~160℃, and 130~140℃, respectively.

6. The method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric according to claim 2, characterized in that, After the base coat is applied and dried, the dry weight of the base fabric increases by 10~15 g / m². 2 The adhesive layer thickness is 0.15±0.02mm.

7. The method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric according to claim 2, characterized in that, In step (7), the top layer adhesive is applied by roller coating. After the top layer adhesive is applied, a three-stage drying process is adopted. The drying temperatures of the first to third stages are 100~110℃, 130~140℃, and 150~170℃, respectively.

8. The method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric according to claim 2, characterized in that, After the surface layer is coated with adhesive and dried, the dry weight of the fabric increases by 12~17g / m². 2 The adhesive layer thickness is 0.15±0.02mm.

9. A method for preparing a moisture-permeable, heat-insulating, and UV-resistant tent fabric according to any one of claims 1 to 8, characterized in that, The breathable, heat-insulating, and UV-resistant tent fabric has a heat-blocking rate >45% and a moisture permeability >3000g / (m²). 2 • 24h), UPF value > 300, T(UVA) AV / % < 2.5, UPF value decreases by ≤ 11% after 50 washes.

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