Hydrological surveying garment fabric based on point-like PUR hot melt glue composite and preparation method thereof

Abstract

This invention relates to the field of special protective clothing fabric technology, and discloses a hydrological surveying suit fabric based on dot-matrix PUR hot melt adhesive composite and its preparation method. The fabric consists of, from the outside in, a first nylon fabric layer, a second PTFE microporous film layer, a third functional sponge layer, a fourth PTFE microporous film layer, and a fifth nylon warp-knitted layer; adjacent layers are bonded together by dot-matrix moisture-curing PUR hot melt adhesive; the third sponge layer is made of modified neoprene rubber, silica aerogel powder, and multilayer graphene, forming an interpenetrating network within. This invention utilizes the thermal insulation properties of aerogel and the electrical conductivity of graphene to synergistically provide long-lasting thermal protection and antistatic functions; the dot-matrix coating combined with the PTFE microporous film ensures waterproof and breathable properties; the step-by-step layering process releases internal stress, and combined with the moisture cross-linking and curing of the PUR hot melt adhesive, effectively prevents interfacial delamination and breakage under extreme cold stress conditions, fully meeting the needs of hydrological surveying operations.

Description

Technical Field

[0001] This invention relates to the field of special protective clothing fabric technology, specifically to hydrological survey clothing fabric based on dotted PUR hot melt adhesive composite and its preparation method. Background Technology

[0002] Hydrological surveying operations are typically conducted in complex and harsh outdoor environments, where surveyors frequently face extreme cold, high humidity, wading, and frequent, vigorous physical activity. This unique working environment places extremely high demands on the overall performance of the fabrics used in surveying workwear. The fabrics must not only possess excellent waterproof and breathable properties to prevent the intrusion of external liquid water and allow sweat to escape from the skin, but also provide long-lasting warmth and insulation, as well as antistatic properties to quickly dissipate electrical charge under friction.

[0003] Currently, most commercially available outdoor waterproof and cold-weather fabrics employ a traditional multi-layer direct composite structure of "outer fabric + waterproof and breathable membrane + thermal lining." This type of traditional composite fabric has significant limitations in practical applications. Firstly, the internal still air layer of traditional thermal insulation layers (such as ordinary rubber sponge or fleece structures) is easily damaged under low temperatures, humidity, or external pressure, leading to a significant decrease in thermal resistance and an inability to provide a stable and durable insulation island effect in extremely cold waters. Secondly, existing composite processes generally use thermoplastic polyurethane hot melt adhesives or surface coating processes. The continuous, dense adhesive film can block the microporous network on the surface of the waterproof and breathable membrane (such as PTFE microporous membrane), greatly increasing the mass transfer resistance of gas molecules and resulting in a severe reduction in moisture permeability.

[0004] Furthermore, due to the inherent differences in tensile modulus of elasticity and thermal shrinkage rate among different material layers, a large amount of internal stress is generated and solidified between the layers during the traditional one-time multi-layer synchronous hot-pressing process. When surveyors perform high-frequency mechanical rubbing or stretching under extremely cold conditions, the traditional physically cross-linked adhesives often undergo low-temperature embrittlement. The accumulated internal stress is concentrated and released at the interface between the adhesive layer and the film, which can easily cause micro-wrinkles, interface delamination, or even film tearing, ultimately leading to the overall failure of the fabric's waterproofing. At the same time, traditional polymer insulation layers and films are excellent insulators. Static charges generated by friction during operation in dry and cold environments can easily accumulate on the surface and inside the fabric. The lack of a continuous three-dimensional conductive network for conduction and dissipation not only affects wearing comfort but may also cause electrostatic interference to precision hydrological surveying instruments.

[0005] Therefore, how to break through the limitations of existing processes and develop a hydrological survey clothing fabric that can perfectly balance high waterproof and breathable properties, long-lasting thermal protection, antistatic function, and excellent anti-peeling structural stability in extremely cold, watery, and frequently stress-altering environments has become a technical problem that urgently needs to be solved in the field of special protective textiles. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a hydrological surveying suit fabric and its preparation method based on dotted PUR hot melt adhesive composite. This solves the technical problems of traditional hydrological surveying suit fabrics, which suffer from poor breathability and moisture permeability while maintaining high waterproofness, resulting in stuffy and hot wear, as well as the stiff feel, heavy weight, and easy aging and delamination caused by traditional full-coating composite processes.

[0007] The technical problem solved by this invention is that existing hydrological survey work clothes are difficult to balance waterproof and breathable properties, long-term thermal protection performance and antistatic function in extremely cold and watery environments. Moreover, the multi-layer composite structure is prone to internal stress accumulation under stress, which leads to interface delamination and fracture.

[0008] To address the above problems, the present invention provides the following technical solution: In a first aspect, the present invention provides a hydrological survey clothing fabric based on dotted PUR hot melt adhesive composite, employing the following technical solution: A hydrological surveying suit fabric based on dotted PUR hot melt adhesive composite comprises, from the outside in, a first nylon fabric layer, a second PTFE microporous film layer, a third functional thin sponge layer, a fourth PTFE microporous film layer, and a fifth nylon warp-knitted layer; adjacent layers are bonded together by dotted, moisture-curing polyurethane hot melt adhesive. The third functional thin sponge layer is made of the following raw materials in parts by weight: 100 parts modified neoprene rubber; 5 to 15 parts silica aerogel powder; 1 to 5 parts multilayer graphene nanosheets; 5.5 parts azodicarbonamide; 3.5 parts magnesium oxide; 4 parts zinc oxide; 15 parts naphthenic oil; and 1.5 parts silane coupling agent. The silica aerogel powder and multilayer graphene nanosheets form an interpenetrating network structure within the third functional thin sponge layer.

[0009] By employing the above technical solutions, silica aerogel possesses a mesoporous structure and high porosity, dispersing within a chloroprene rubber matrix to form a discontinuous heat-insulating phase. The mean free path of gas molecules within the mesopores is limited, reducing convective heat transfer and gas-phase heat conduction; the low-density characteristics of the aerogel extend the heat conduction path of the solid matrix. Multilayer graphene nanosheets possess a two-dimensional conductive structure. When the volume fraction of multilayer graphene nanosheets in the rubber system reaches the percolation threshold, a continuous three-dimensional electron transport network is established within the polymer matrix, and static charges accumulated from external friction are conducted and dissipated along this continuous pathway. Adjacent composite layers are coated with moisture-curing polyurethane hot melt adhesive in a dotted pattern, while the PTFE film not in contact with the adhesive retains its original microporous morphology. Moisture vapor emitted by the human body diffuses through the gaps in the fabric yarns into the unobstructed microporous channels, maintaining moisture permeability; the microporous scale, combined with the low surface energy properties of the PTFE material, effectively blocks the intrusion of external liquid moisture, achieving hydrostatic pressure resistance.

[0010] Preferably, the raw materials are in the following weight proportions: 100 parts modified chloroprene rubber, 10 parts silica aerogel powder, 3 parts multilayer graphene nanosheets, 5.5 parts azodicarbonamide, 3.5 parts magnesium oxide, 4 parts zinc oxide, 15 parts naphthenic oil, and 1.5 parts silane coupling agent. The average particle size of the silica aerogel powder is 60 to 80 nm; the average thickness of the multilayer graphene nanosheets is 6 to 7 nm. The first nylon fabric layer has a basis weight of 180 to 220 g / m². 2 The fabric consists of 330D nylon 66 filament fabric; the second and fourth PTFE microporous film layers have a thickness of 15 to 25 μm, an average pore size of 0.3 μm, and a porosity of 75% to 85%; the fifth nylon warp-knitted layer has a basis weight of 35 to 45 g / m². 2 20D nylon twill warp-knitted fabric. The isocyanate group content of the moisture-curing polyurethane hot melt adhesive is 3.2% to 3.8%; the dot density of the moisture-curing polyurethane hot melt adhesive is 25 to 50 dots / cm². 2 The amount of adhesive applied is 10 to 25 g / m. 2 .

[0011] By adopting the above technical solution and setting a specific ratio of aerogel to graphene, excessive powder addition is prevented from disrupting the uniformity of the cell walls during cross-linking and foaming, thus ensuring the tensile strength of the sponge matrix. By limiting the pore size of the film and the dotted arrangement parameters of the polyurethane hot melt adhesive, sufficient uncoated, permeable area is maintained while meeting the requirements for the number of physical anchoring points and chemical bonding strength at the interface.

[0012] Secondly, the present invention provides a method for preparing hydrological survey clothing fabric based on dotted PUR hot melt adhesive composite, employing the following technical solution: A method for preparing hydrological survey clothing fabric based on dotted PUR hot melt adhesive composite includes the following steps: providing modified chloroprene rubber, silica aerogel powder, multilayer graphene nanosheets, azodicarbonamide, magnesium oxide, zinc oxide, naphthenic oil, and silane coupling agent as raw materials; mixing, sheeting, and storing the raw materials; simultaneously foaming and cross-linking vulcanization in a mold; and finally cooling and slicing to obtain a third functional thin sponge layer; heating and melting moisture-curing polyurethane hot melt adhesive; applying it dottedly to the inner surface of the first nylon fabric layer; then bonding it to the second PTFE microporous film layer using a pressure roller; and finally applying dottedly to the uncomposite surface of the second PTFE microporous film layer. The first step involves applying a transfer coating and bonding it to the third functional thin sponge layer using a pressure roller, then winding it up to obtain a three-in-one semi-finished product. Next, a moisture-curing polyurethane hot melt adhesive is heated and melted, then applied in a dotted transfer coating to the inner surface of the fifth nylon warp-knitted layer. This is then bonded to the fourth PTFE microporous film layer using a pressure roller, and wound up to obtain a two-in-one semi-finished product. Finally, a moisture-curing polyurethane hot melt adhesive is dotted transfer coated onto the surface of the third functional thin sponge layer of the three-in-one semi-finished product, and then simultaneously pressed with the fourth PTFE microporous film layer of the two-in-one semi-finished product using a main composite pressure roller, and wound up to obtain a five-layer composite fabric roll. This five-layer composite fabric roll is then transferred to a constant temperature and humidity curing chamber for static storage and curing treatment to obtain the finished product.

[0013] By adopting the above technical solutions, the step-by-step layering process can release the internal stress accumulated due to the difference in elastic modulus and thermal shrinkage rate between different fabric materials. The stress generated by direct multi-layer lamination is easily solidified at the interface, while step-by-step lamination allows the adhesive layer time for stress relaxation during the initial moisture curing stage, avoiding shear failure and micro-wrinkling. The resting operation after chloroprene rubber compounding reduces the internal stress within the molecular chains. During the vulcanization stage, zinc oxide catalyzes the cross-linking of rubber molecular chains with metal oxides, establishing a polymer network structure, while magnesium oxide absorbs the hydrogen chloride released during the reaction, playing a role in preventing scorching.

[0014] The moisture crosslinking and curing process of polyurethane hot melt adhesive can be divided into the following two main reaction steps: In the first step, water molecules in the environment diffuse and penetrate into the colloid. The water molecules react with the free terminal isocyanate groups to generate an unstable carbamic acid intermediate. This intermediate decomposes rapidly, releasing carbon dioxide gas and transforming into a primary amine with active hydrogen.

[0015] In the second step, the active primary amine generated in the system further combines with the unreacted terminal isocyanate groups to generate substituted urea bond structures with strong cohesive energy and hydrogen bonding through a polycondensation reaction, thereby constructing a highly cross-linked polyurethane urea network.

[0016] The generation of a three-dimensional macromolecular network transforms the composite interface of the fabric from a single mechanical filling and interlocking to a dual system of physical anchoring and irreversible chemical bonding, ensuring that the adhesive layer does not untangle or slip under extreme temperature changes and high-frequency mechanical rubbing.

[0017] Preferably, the process prior to mixing includes the preparation of a functional powder paste dispersion: placing silica aerogel powder and multilayer graphene nanosheets in a mixer, spraying silane coupling agent and a portion of naphthenic oil at 80°C, and premixing at low speed to form a functional powder paste dispersion. During the preparation of the third functional thin sponge layer, the process parameters for simultaneous foaming and cross-linking vulcanization are: mold clamping pressure of 12.5 MPa, heating temperature of 160°C to 180°C, and holding time of 8 to 15 minutes. The process parameters for dot-matrix transfer coating and pressing are: the heating and melting temperature of the moisture-curing polyurethane hot melt adhesive is controlled at 110 to 140°C; the pressure of the pressure roller and the main composite pressure roller is set to 1.5 to 4.5 kg / cm². 2 The compounding speed is controlled between 15 and 35 m / min. The environmental parameters for the curing treatment are: temperature controlled between 22℃ and 40℃, relative humidity controlled between 50% and 90%, and the standing time is at least 48 hours.

[0018] By employing the above technical solution, the alkoxy end groups of the silane coupling agent first hydrolyze, condense, and anchor onto the surface of the inorganic powder. The organic groups at the other end are miscible with the low-polarity naphthenic oil and polymer segments, improving the wetting effect of the powder in the initial stage of mixing and preventing agglomeration caused by dry friction. The foaming and vulcanization parameters synchronize the gas release rate of azodicarbonamide with the curing rate of the rubber crosslinking network, preventing gas escape from the uncrosslinked fluid and causing cell rupture. The coating melting temperature and the pressure parameters of the composite roller control the interfacial rheological properties of the hot melt adhesive, ensuring that the initially viscous adhesive is embedded in the fiber bundle voids and establishes initial interlayer bonding force. Controlled temperature, humidity, and settling time provide the concentration gradient required for water vapor diffusion and the activation energy for polyurethane segment collisions, completing the curing and crosslinking reaction.

[0019] This invention provides a hydrological surveying suit fabric based on dotted PUR hot melt adhesive and its preparation method. It has the following beneficial effects: 1. The third functional thin sponge layer of this invention incorporates silica aerogel powder and multilayer graphene nanosheets, which together form an interpenetrating network structure within a modified chloroprene rubber matrix. The mesoporous structure of the silica aerogel restricts the mean free path of gas molecules, reducing thermal conductivity. The multilayer graphene nanosheets establish continuous electron transport channels within the polymer matrix. This technical feature provides both cold-proof and heat-insulating properties while also conducting and dissipating static electricity generated by friction, meeting the special environmental requirements of hydrological surveys.

[0020] 2. This invention uses a dot-distributed moisture-curing polyurethane hot melt adhesive to bond the nylon fabric layer, the polytetrafluoroethylene microporous film layer, and the sponge layer. The dot-coating process preserves the microporous morphology of the areas of the polytetrafluoroethylene film that are not in contact with the adhesive, and utilizes the micropore size and the low surface energy of the material to block the intrusion of liquid moisture. Moisture vapor emitted by the human body can diffuse through the unobstructed microporous channels, ensuring the overall waterproof and breathable performance of the fabric.

[0021] 3. This invention enhances the structural stability of composite fabrics by using a step-by-step layered bonding preparation method combined with the moisture-curing crosslinking reaction of polyurethane hot melt adhesive; the step-by-step bonding releases the internal stress accumulated by the differences in elastic modulus and thermal shrinkage rate of different materials; the colloid generates a three-dimensional crosslinking network during the curing process, so that the fabric interface forms a dual combination of physical anchoring and chemical bonding, preventing interface delamination and breakage under extreme cold alternation and mechanical rubbing. Attached Figure Description

[0022] Figure 1 This is a comparative distribution diagram of the test data of thermal conductivity of various samples in this invention; Figure 2 This is a logarithmic scale comparison distribution of the volume resistivity test data of each sample in this invention; Figure 3 This is a comparative distribution chart of the electrostatic decay time test data for each sample of the present invention; Figure 4 This is a line graph showing the change in 180° peel strength of various fabric samples under different curing times according to the present invention. Figure 5 A bar chart comparing the tensile deformation rates of various fabric samples under different stress directions in this invention. Figure 6 This is a biaxial comparison diagram of the thermal protection performance of different structural composite fabrics of the present invention; Figure 7 This is a biaxial comparison diagram of the dynamic waterproof and breathable balance of various fabric samples of the present invention; Figure 8 This is a grouped bar chart comparing the peel strength before and after high and low temperature cycling of the present invention; Figure 9 This is a biaxial line graph illustrating the effect of the washing cycle of the present invention on the antistatic stability of the composite fabric. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings, preparation examples, embodiments, comparative examples, and test examples. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Preparation Examples 1-5: Preparation Example 1: This preparation example provides a method for preparing a functional thin sponge (used as the third layer of a composite fabric), comprising the following steps: (1) Component preparation: Accurately weigh the following commercially available standard specifications of raw materials by weight: 100 parts modified chloroprene rubber (CR), 10 parts silica (SiO2) aerogel powder (average particle size approximately 70nm), 3 parts multilayer graphene nanosheets (average thickness approximately 6.5nm), 5.5 parts azodicarbonamide (AC foaming agent), 3.5 parts magnesium oxide, 4 parts zinc oxide, 15 parts naphthenic oil (softener), and 1.5 parts silane coupling agent (such as KH-560).

[0025] (2) Functional powder pretreatment: SiO2 aerogel powder and multilayer graphene nanosheets were placed in a high-speed mixer, and silane coupling agent and some naphthenic oil were sprayed on. The mixture was premixed into a paste-like dispersion by low-speed stirring at 80°C to prevent the nanoparticles from scattering or agglomerating during subsequent mixing.

[0026] (3) Mixing and film output: The prepared chloroprene rubber matrix was fed into a two-roll mill for initial plasticizing. After wrapping the rolls, magnesium oxide was first added for anti-scorching treatment. Subsequently, the pretreated functional paste dispersion and the remaining naphthenic oil were gradually added. The roller temperature of the two-roll mill was kept constant at 50°C, and mixing was continued for 15 minutes. Finally, 3-5 minutes before sheeting, zinc oxide and AC foaming agent were added, and uniform dispersion was ensured through operations such as triangular wrapping and thin-passing. After mixing, the sheet was sheeted, and the sheet thickness was controlled to be 3mm.

[0027] (4) Parking and stress relief: The resulting compounded film was laid flat in a dark environment at room temperature (about 25°C) and left to stand for 18 hours to eliminate the internal stress of the molecular chains accumulated during the compounding process.

[0028] (5) Foaming and cross-linking vulcanization: After the rubber sheets have been placed in the mold, they are cut to the required size and transferred to the flat vulcanizing machine. The mold closing pressure is set to 12.5 MPa and the heating temperature to 170℃. At this temperature, zinc oxide catalyzes the decomposition of AC foaming agent to produce gas, while simultaneously triggering the metal oxide crosslinking reaction of chloroprene rubber. The process is then carried out under heat and pressure for 12 minutes for foaming and vulcanization.

[0029] (6) Cooling and fine sectioning: After the foaming process is completed, the sponge is cooled and demolded. A precision slicing machine is used to remove the surface skin layer and cut it into thin slices with a thickness of 1.0 mm, thus obtaining the functional thin sponge with the standard formula.

[0030] Preparation Example 2: This preparation example provides a method for preparing a functional thin sponge with high aerogel content and low graphene content (used as the third layer of a composite fabric), including the following steps: (1) Component preparation: Accurately weigh the following commercially available standard specifications of raw materials by weight: 100 parts modified chloroprene rubber (CR), 15 parts silica (SiO2) aerogel powder (average particle size approximately 70nm), 1 part multilayer graphene nanosheets (average thickness approximately 6.5nm), 5.5 parts azodicarbonamide (AC foaming agent), 3.5 parts magnesium oxide, 4 parts zinc oxide, 15 parts naphthenic oil (softener), and 1.5 parts silane coupling agent (such as KH-560).

[0031] (2) Functional powder pretreatment: SiO2 aerogel powder and multilayer graphene nanosheets were placed in a high-speed mixer, and silane coupling agent and some naphthenic oil were sprayed on. The mixture was premixed into a paste-like dispersion by low-speed stirring at 80°C to prevent the nanoparticles from scattering or agglomerating during subsequent mixing.

[0032] (3) Mixing and film output: The prepared chloroprene rubber matrix was fed into a two-roll mill for initial plasticizing. After wrapping the rolls, magnesium oxide was first added for anti-scorching treatment. Subsequently, the pretreated functional paste dispersion and the remaining naphthenic oil were gradually added. The roller temperature of the two-roll mill was kept constant at 50°C, and mixing was continued for 15 minutes. Finally, 3-5 minutes before sheeting, zinc oxide and AC foaming agent were added, and uniform dispersion was ensured through operations such as triangular wrapping and thin-passing. After mixing, the sheet was sheeted, and the sheet thickness was controlled to be 3mm.

[0033] (4) Parking and stress relief: The resulting compounded rubber sheet was laid flat in a dark environment at room temperature (about 25°C) and left to stand for 18 hours to eliminate internal stress and allow the compounding agent to penetrate more evenly.

[0034] (5) Foaming and cross-linking vulcanization: After the film has been placed, it is cut to size and placed in a mold before being transferred to a flat vulcanizing machine. The mold closing pressure of the flat vulcanizing machine is set to 12.5 MPa, the heating temperature is set to 170℃, and simultaneous foaming and cross-linking vulcanization treatment is performed. The heat and pressure holding time is set to 12 minutes.

[0035] (6) Cooling and fine sectioning: After the foaming process is completed and cooled to room temperature, the sponge is demolded. The block sponge is then transversely slit using a precision slitting machine to remove the surface skin layer and finely slit it into thin slices with a thickness of 1.0 mm, thus obtaining a functional thin sponge with high aerogel content and low graphene ratio.

[0036] Preparation Example 3: This preparation example provides a method for preparing a functional thin sponge with low aerogel content and high graphene content, including the following steps: (1) Component preparation: Accurately weigh 100 parts of modified chloroprene rubber, 5 parts of silica (SiO2) aerogel powder, 5 parts of multilayer graphene nanosheets, 5.5 parts of azodicarbonamide, 3.5 parts of magnesium oxide, 4 parts of zinc oxide, 15 parts of naphthenic oil, and 1.5 parts of silane coupling agent (such as KH-560) by weight.

[0037] (2) Functional powder pretreatment: SiO2 aerogel powder and multilayer graphene nanosheets were placed in a high-speed mixer, and silane coupling agent and some naphthenic oil were sprayed on. The mixture was premixed into a paste-like dispersion by low-speed stirring at 80°C to prevent the nanoparticles from scattering or agglomerating during subsequent mixing.

[0038] (3) Mixing and film output: Modified chloroprene rubber was initially plasticized in a two-roll mill. After wrapping the rolls, magnesium oxide was first added for anti-scorching treatment. Subsequently, the pretreated functional paste dispersion and the remaining naphthenic oil were gradually added. The roller temperature of the two-roll mill was kept constant at 50°C, and mixing was continued for 15 minutes. Finally, 3-5 minutes before sheeting, zinc oxide and AC foaming agent were added, and uniform dispersion was ensured through operations such as triangular wrapping and thin-passing. After mixing, the sheets were sheeted, and the sheet thickness was controlled to be 3 mm.

[0039] (4) Parking and stress relief: The resulting compounded rubber sheet was laid flat in a dark environment at room temperature (25°C) and left to stand for 18 hours.

[0040] (5) Foaming and cross-linking vulcanization: After the film has been placed in the mold, it is cut and transferred to the flat vulcanizing machine. The mold closing pressure of the flat vulcanizing machine is set to 12.5 MPa, the heating temperature is set to 170℃, and simultaneous foaming and cross-linking vulcanization treatment is performed for 12 minutes.

[0041] (6) Cooling and fine sectioning: After the foaming process is completed and cooled to room temperature, the sponge is demolded. The block sponge is then cut using a precision slicing machine to remove the surface skin layer and cut into thin slices with a thickness of 1.0 mm.

[0042] Preparation Example 4: This preparation example provides a method for preparing functional thin sponges using the highest foaming temperature and the shortest vulcanization time, including the following steps: (1) Component preparation: Accurately weigh 100 parts of modified chloroprene rubber, 10 parts of silica (SiO2) aerogel powder, 3 parts of multilayer graphene nanosheets, 5.5 parts of azodicarbonamide, 3.5 parts of magnesium oxide, 4 parts of zinc oxide, 15 parts of naphthenic oil, and 1.5 parts of silane coupling agent (such as KH-560) by weight.

[0043] (2) Functional powder pretreatment: SiO2 aerogel powder and multilayer graphene nanosheets were placed in a high-speed mixer, and silane coupling agent and some naphthenic oil were sprayed on. The mixture was premixed into a paste-like dispersion by low-speed stirring at 80°C to prevent the nanoparticles from scattering or agglomerating during subsequent mixing.

[0044] (3) Mixing and film output: Modified chloroprene rubber was initially plasticized in a two-roll mill. After wrapping the rolls, magnesium oxide was first added for anti-scorching treatment. Subsequently, the pretreated functional paste dispersion and the remaining naphthenic oil were gradually added. The roller temperature of the two-roll mill was kept constant at 50°C, and mixing was continued for 15 minutes. Finally, 3-5 minutes before sheeting, zinc oxide and AC foaming agent were added, and uniform dispersion was ensured through operations such as triangular wrapping and thin-passing. After mixing, the sheets were sheeted, and the sheet thickness was controlled to be 3 mm.

[0045] (4) Parking and stress relief: The resulting compounded rubber sheet was laid flat in a dark environment at room temperature (25°C) and left to stand for 18 hours.

[0046] (5) Foaming and cross-linking vulcanization: After the film has been placed in the mold, it is cut and transferred to the flat vulcanizing machine. The mold closing pressure of the flat vulcanizing machine is set to 12.5 MPa, the heating temperature is set to 180℃, and simultaneous foaming and cross-linking vulcanization treatment is performed for 8 minutes.

[0047] (6) Cooling and fine sectioning: After the foaming process is completed and cooled to room temperature, the sponge is demolded. The block sponge is then cut using a precision slicing machine to remove the surface skin layer and cut into thin slices with a thickness of 1.0 mm.

[0048] Preparation Example 5: This preparation example provides a method for preparing functional thin sponges using the lowest foaming temperature and the longest vulcanization time, including the following steps: (1) Component preparation: Accurately weigh 100 parts of modified chloroprene rubber, 10 parts of silica (SiO2) aerogel powder, 3 parts of multilayer graphene nanosheets, 5.5 parts of azodicarbonamide, 3.5 parts of magnesium oxide, 4 parts of zinc oxide, 15 parts of naphthenic oil, and 1.5 parts of silane coupling agent (such as KH-560) by weight.

[0049] (2) Functional powder pretreatment: SiO2 aerogel powder and multilayer graphene nanosheets were placed in a high-speed mixer, and silane coupling agent and some naphthenic oil were sprayed on. The mixture was premixed into a paste-like dispersion by low-speed stirring at 80°C to prevent the nanoparticles from scattering or agglomerating during subsequent mixing.

[0050] (3) Mixing and film output: Modified chloroprene rubber was initially plasticized in a two-roll mill. After wrapping the rolls, magnesium oxide was first added for anti-scorching treatment. Subsequently, the pretreated functional paste dispersion and the remaining naphthenic oil were gradually added. The roller temperature of the two-roll mill was kept constant at 50°C, and mixing was continued for 15 minutes. Finally, 3-5 minutes before sheeting, zinc oxide and AC foaming agent were added, and uniform dispersion was ensured through operations such as triangular wrapping and thin-passing. After mixing, the sheets were sheeted, and the sheet thickness was controlled to be 3 mm.

[0051] (4) Parking and stress relief: The resulting compounded rubber sheet was laid flat in a dark environment at room temperature (25°C) and left to stand for 18 hours.

[0052] (5) Foaming and cross-linking vulcanization: After the film has been placed in the mold, it is cut and transferred to the flat vulcanizing machine. The mold closing pressure of the flat vulcanizing machine is set to 12.5 MPa, the heating temperature is set to 160℃, and simultaneous foaming and cross-linking vulcanization treatment is performed for 15 minutes.

[0053] (6) Cooling and fine sectioning: After the foaming process is completed and cooled to room temperature, the sponge is demolded. The block sponge is then cut using a precision slicing machine to remove the surface skin layer and cut into thin slices with a thickness of 1.0 mm.

[0054] Examples 1-5: Example 1: This embodiment provides a method for preparing hydrological survey clothing fabric based on dotted PUR hot melt adhesive composite, including the following steps: (1) Raw material preparation: Prepare commercially available rolls of material with the following specifications: the first layer has a weight of 200g / m². 2 The first layer is a 330D nylon 66 filament fabric; the second and fourth layers are both expanded polytetrafluoroethylene (PTFE) microporous films with a thickness of 20 μm, an average pore size of 0.3 μm, and a porosity of 80%; the third layer is a functional thin sponge with a thickness of 1.0 mm prepared in Preparation Example 1; the fifth layer is a 40 g / m² filament fabric. 2 20D Tricot warp-knitted fabric. Prepare moisture-curing polyurethane (PUR) hot melt adhesive with an isocyanate group (-NCO) content of approximately 3.5%.

[0055] (2) First stage point-like composite (1+2+3 layers bonded): Start the rotary roller transfer coating laminator and heat the PUR hot melt adhesive to 125℃ to melt it. Pass the first layer of 330D nylon 66 fabric as the substrate through the coating system, and transfer the molten PUR hot melt adhesive onto the inner surface of the fabric using a dot-matrix engraving roller. Control the median coating parameters: adhesive application rate is 18 g / m². 2 The density of the dots is 35 dots / cm. 2 .

[0056] Immediately after applying the adhesive, the first layer of fabric is bonded to the second layer of PTFE film using a composite pressure roller, with the roller pressure set to 3.2 kg / cm². 2 .

[0057] Subsequently, the above adhesive application process was repeated on the uncoated surface of the second PTFE membrane (melt temperature 125℃, adhesive application amount 18g / m²). 2 The density of the dots is 35 dots / cm. 2 And through the pressure roller (pressure 3.2 kg / cm) 2 It is then bonded to a third layer of functional thin sponge and rolled up to obtain a "three-in-one" semi-finished product.

[0058] (3) Second stage point-like composite (4+5 layers): On the laminating equipment, the PUR hot melt adhesive is heated to 125°C to melt. Using the fifth layer of 20D nylon tar fabric as the substrate, the PUR hot melt adhesive is applied using the same roller transfer process (adhesive application rate 18g / m²). 2 The density of the dots is 35 dots / cm. 2 Then, it is bonded to the fourth PTFE membrane using a pressure roller, with the lamination speed controlled at 25 m / min and the lamination pressure set at 2.5 kg / cm². 2 They obtained a "two-in-one" semi-finished product.

[0059] (4) Final lamination (overall full-width bonding): The "three-in-one" semi-finished product obtained in step (2) (third layer of sponge facing up) and the "two-in-one" semi-finished product obtained in step (3) (fourth layer of PTFE membrane facing down) are introduced into the composite host. PUR hot melt adhesive (melt temperature 125℃, adhesive application amount 18g / m²) is applied to the surface of the third layer of sponge using the same dot transfer process. 2 The density of the dots is 35 dots / cm. 2 ), through the main composite pressure roller (pressure 3.0 kg / cm), 2 (At a composite speed of 25m / min) the two semi-finished products are pressed together simultaneously and then wound up to obtain a five-layer composite fabric roll.

[0060] (5) Curing and cross-linking: The rolled-up full-width composite fabric is transferred to a constant temperature and humidity curing chamber. The standard conditions for the curing chamber are set as follows: constant temperature of 32℃ and relative humidity (RH) controlled at 75%. Under these conditions, the fabric is left to stand for 48 hours to allow the -NCO groups in the PUR hot melt adhesive to fully undergo an irreversible polyurethane crosslinking reaction (bridging reaction) with the moisture in the environment. After curing, the finished hydrological survey clothing fabric with high hydrostatic pressure and high moisture permeability is obtained.

[0061] Example 2: This embodiment provides a method for preparing hydrological survey clothing fabric based on dotted PUR hot melt adhesive composite, including the following steps: (1) Raw material preparation: Prepare commercially available rolls of material with the following specifications: the first layer has a weight of 200g / m². 2 The first layer is a 330D nylon 66 filament fabric; the second and fourth layers are both expanded polytetrafluoroethylene (PTFE) microporous films with a thickness of 20 μm, an average pore size of 0.3 μm, and a porosity of 80%; the third layer is a functional thin sponge with a thickness of 1.0 mm (high aerogel, low graphene ratio) prepared in Preparation Example 2; the fifth layer is a 40 g / m² fabric. 2 20D Tricot warp-knitted fabric. Prepare moisture-curing polyurethane (PUR) hot melt adhesive with an isocyanate group (-NCO) content of approximately 3.5%.

[0062] (2) First stage point-like composite (1+2+3 layers bonded): Start the rotary roller transfer coating laminator and heat the PUR hot melt adhesive to 110℃ to melt it. Pass the first layer of 330D nylon 66 fabric as the substrate through the coating system, and transfer the molten PUR hot melt adhesive onto the inner surface of the fabric using a dot-matrix engraving roller. Control the lower limit of the coating parameters: adhesive application rate is 10g / m². 2 The density of the dots is 25 dots / cm. 2 .

[0063] Immediately after applying the adhesive, the first layer of fabric is bonded to the second layer of PTFE film using a composite pressure roller, with the roller pressure set to 2.0 kg / cm². 2 .

[0064] Subsequently, the above adhesive application process was repeated on the uncoated surface of the second PTFE membrane (melt temperature 110℃, adhesive application amount 10g / m²). 2 The density of the dots is 25 dots / cm. 2 And through the pressure roller (pressure 2.0 kg / cm) 2 It is then bonded to a third layer of functional thin sponge and rolled up to obtain a "three-in-one" semi-finished product.

[0065] (3) Second stage point-like composite (4+5 layers): On the laminating equipment, the PUR hot melt adhesive is heated to 110°C to melt. Using the fifth layer of 20D nylon tar fabric as the substrate, the PUR hot melt adhesive is applied using the same roller transfer process (adhesive application rate 10g / m²). 2 The density of the dots is 25 dots / cm. 2 Then, it is bonded to the fourth PTFE membrane using a pressure roller, with the lamination speed controlled at 15 m / min and the lamination pressure set at 1.5 kg / cm². 2 They obtained a "two-in-one" semi-finished product.

[0066] (4) Final lamination (overall full-width bonding): The "three-in-one" semi-finished product obtained in step (2) (third layer of sponge facing up) and the "two-in-one" semi-finished product obtained in step (3) (fourth layer of PTFE membrane facing down) are introduced into the composite host. PUR hot melt adhesive (melt temperature 110℃, adhesive application amount 10g / m) is applied to the surface of the third layer of sponge using the same dot transfer process. 2 The density of the dots is 25 dots / cm. 2 ), through the main composite pressure roller (pressure 1.5kg / cm), 2 (At a composite speed of 15m / min) the two semi-finished products are pressed together simultaneously and then rolled up to obtain a five-layer composite fabric roll.

[0067] (5) Curing and cross-linking: The wound-up full-width composite fabric is transferred to a constant temperature and humidity curing chamber. The curing chamber parameters are set to the lower limit conditions: constant temperature of 25℃ and relative humidity (RH) controlled at 60%. Under these conditions, the fabric is left to stand for 48 hours to allow the PUR hot melt adhesive to undergo a cross-linking reaction. After curing, the finished composite fabric is obtained.

[0068] Example 3: This embodiment provides a method for preparing hydrological survey clothing fabric based on dotted PUR hot melt adhesive composite, including the following steps: (1) Raw material preparation: Prepare commercially available rolls of material with the following specifications: the first layer has a weight of 200g / m². 2 The first layer is a 330D nylon 66 filament fabric; the second and fourth layers are both expanded polytetrafluoroethylene (PTFE) microporous films with a thickness of 20 μm, an average pore size of 0.3 μm, and a porosity of 80%; the third layer is a functional thin sponge with a thickness of 1.0 mm (low aerogel, high graphene ratio) prepared in Preparation Example 3; the fifth layer is a 40 g / m² filament fabric. 2 20D Tricot warp-knitted fabric. Prepare moisture-curing polyurethane (PUR) hot melt adhesive with an isocyanate group (-NCO) content of approximately 3.5%.

[0069] (2) First stage point-like composite (1+2+3 layers bonded): Start the rotary roller transfer coating laminator and heat the PUR hot melt adhesive to 140℃ to melt it. Pass the first layer of 330D nylon 66 fabric as the substrate through the coating system, and transfer the molten PUR hot melt adhesive onto the inner surface of the fabric using a dot-matrix engraving roller. Control the upper limit of the coating parameters: adhesive application rate is 25g / m². 2 The density of the dots is 50 dots / cm. 2 .

[0070] Immediately after applying the adhesive, the first layer of fabric is bonded to the second layer of PTFE film using a composite pressure roller, with the roller pressure set to 4.5 kg / cm². 2 (Parameter upper limit).

[0071] Subsequently, the above adhesive application process was repeated on the uncoated surface of the second PTFE membrane (melt temperature 140℃, adhesive application amount 25g / m²). 2 Distribution density: 50 dots / cm 2 ), and through the pressure roller (pressure 4.5 kg / cm) 2 It is then bonded to a third layer of functional thin sponge and rolled up to obtain a "three-in-one" semi-finished product.

[0072] (3) Second stage point-like composite (4+5 layers): On the laminating equipment, the PUR hot melt adhesive is heated to 140°C to melt. Using the fifth layer of 20D nylon tar fabric as the substrate, the PUR hot melt adhesive is applied using the same roller transfer process (adhesive application rate 25g / m²). 2 Distribution density: 50 dots / cm 2 Then, it is bonded to the fourth PTFE membrane using a pressure roller, with the lamination speed controlled at 35 m / min and the lamination pressure set at 3.5 kg / cm². 2 They obtained a "two-in-one" semi-finished product.

[0073] (4) Final lamination (overall full-width bonding): The "three-in-one" semi-finished product obtained in step (2) (third layer of sponge facing up) and the "two-in-one" semi-finished product obtained in step (3) (fourth layer of PTFE membrane facing down) are introduced into the composite host. PUR hot melt adhesive (melt temperature 140℃, adhesive application amount 25g / m²) is applied to the surface of the third layer of sponge using the same dot transfer process. 2 Distribution density: 50 dots / cm 2 ), through the main composite pressure roller (pressure 4.0 kg / cm), 2 At a composite speed of 35m / min, the two semi-finished products are pressed together simultaneously and then wound up to obtain a five-layer composite fabric roll.

[0074] (5) Curing and cross-linking: The wound-up full-width composite fabric is transferred to a constant temperature and humidity curing chamber. The curing chamber parameters are set to the upper limit: constant temperature of 40℃ and relative humidity (RH) controlled at 90%. Under these conditions, the fabric is left to stand for 48 hours to allow the PUR hot melt adhesive to undergo a full cross-linking reaction. After curing, a finished composite fabric with extremely high adhesion strength is obtained, but its moisture permeability fluctuates depending on the amount of adhesive used.

[0075] Example 4: This embodiment provides a method for preparing hydrological survey clothing fabric based on a variable parameter bonding process, including the following steps: (1) Raw material preparation: Prepare commercially available rolls of material with the following specifications: the first layer has a weight of 200g / m². 2 The first layer is a 330D nylon 66 filament fabric; the second and fourth layers are both expanded polytetrafluoroethylene (PTFE) microporous films with a thickness of 20 μm, an average pore size of 0.3 μm, and a porosity of 80%; the third layer is a functional thin sponge (obtained by high foaming temperature and short vulcanization time) prepared in Example 4; the fifth layer is a 40 g / m² fabric. 2 20D Tricot warp-knitted fabric. Prepare moisture-curing polyurethane (PUR) hot melt adhesive (-NCO content approximately 3.5%).

[0076] (2) First stage point-like composite (1+2+3 layers bonded): Start the rotary roller transfer coating laminator and heat the PUR hot melt adhesive to 130℃. Using the first layer of 330D nylon 66 fabric as the substrate, apply the adhesive in dots using a sculpted roller, controlling the adhesive application rate to 18g / m². 2 The density of the dots is 35 dots / cm. 2 .

[0077] After applying the adhesive, the first layer of fabric is bonded to the second layer of PTFE film using a composite pressure roller, with the roller pressure adjusted to a relatively high 4.2 kg / cm². 2To verify the structural stability of the PTFE membrane under high pressure.

[0078] Subsequently, the unlaminated surface of the second PTFE membrane was coated with adhesive using the same parameters and then bonded to the third functional thin sponge. The lamination speed was adjusted to 30 m / min to verify the bonding smoothness of the equipment under high-speed operation.

[0079] (3) Second stage point-like composite (4+5 layers): The PUR hot melt adhesive was heated to 130°C to melt. The fifth layer of 20D nylon woven fabric was then applied in dots (18 g / m²) as the substrate. 2 35 points / cm 2 Then, it was laminated with the fourth PTFE membrane using a pressure roller, with the lamination speed set at 30 m / min and the lamination pressure set at 3.2 kg / cm². 2 By observing whether there is any deviation or wrinkling through high-speed winding, a "two-in-one" semi-finished product is obtained.

[0080] (4) Final lamination (overall full-width bonding): The aforementioned "three-in-one" and "two-in-one" semi-finished products are introduced into the composite main unit. PUR hot melt adhesive (18g / m²) is then transferred in dots onto the surface of the third layer of sponge. 2 35 points / cm 2 The main composite pressure roller is used for synchronous pressing. The pressure of the main pressure roller is set to 3.8 kg / cm². 2 The composite speed was maintained at 30m / min, and the focus was on examining the physical interlocking effect between layers under high-speed and high-pressure conditions after multiple layers were stacked.

[0081] (5) Curing and cross-linking: The finished roll is transferred to the curing room. Standard curing conditions are set: temperature 32℃, relative humidity 75%, and static storage for 48 hours. After curing, observe whether there is interlayer slippage or glue seepage due to excessive pressure in the fabric; the composite fabric product is then obtained.

[0082] Example 5: This embodiment provides a method for preparing hydrological survey clothing fabric based on moisture-curing environment control, including the following steps: (1) Raw material preparation: Prepare commercially available rolls of material with the following specifications: the first layer has a weight of 200g / m². 2 The first layer is a 330D nylon 66 filament fabric; the second and fourth layers are both expanded polytetrafluoroethylene (PTFE) microporous films with a thickness of 20 μm, an average pore size of 0.3 μm, and a porosity of 80%; the third layer is a functional thin sponge prepared in Example 5 (obtained at the lowest foaming temperature and the longest vulcanization time); the fifth layer is a 40 g / m² fabric. 220D Tricot warp-knitted fabric. Prepare moisture-curing polyurethane (PUR) hot melt adhesive (-NCO content approximately 3.5%).

[0083] (2) First stage point-like composite (1+2+3 layers bonded): Start the roller transfer coating laminator and heat the PUR hot melt adhesive to 125℃. Use the median process parameters: adhesive application rate of 18g / m². 2 The density of the dots is 35 dots / cm. 2 The first layer of fabric, the second layer of PTFE film, and the third layer of functional thin sponge are sequentially bonded together using a composite pressure roller. The pressure of the roller is set to 3.2 kg / cm². 2 The compounding speed is 25m / min, and a "three-in-one" semi-finished product is obtained.

[0084] (3) Second stage point-like composite (4+5 layers): The PUR hot melt adhesive was heated to 125°C and melted. The fifth layer of nylon ductile fabric was then applied in dots (18 g / m²). 2 35 points / cm 2 Then, it is bonded to the fourth PTFE membrane using a pressure roller, with the composite pressure set at 2.5 kg / cm². 2 The composite speed is 25m / min, and the "two-in-one" semi-finished product is obtained.

[0085] (4) Final lamination (overall full-width bonding): The aforementioned "three-in-one" and "two-in-one" semi-finished products are introduced into the composite main unit. PUR hot melt adhesive (18g / m²) is then transferred in dots onto the surface of the third layer of sponge. 2 35 points / cm 2 The main composite pressure roller is used for synchronous pressing. The pressure of the main pressure roller is set to 3.0 kg / cm². 2 The composite speed is 25m / min, and the roll is wound up to obtain a five-layer composite fabric roll.

[0086] (5) Extreme environmental maturation and cross-linking: The laminated fabric roll was transferred to a controlled curing chamber. Challenging low-standard curing conditions were set: ambient temperature reduced to 22°C and relative humidity (RH) reduced to 50%. Under these conditions, the mixture was left to stand for 48 hours. Since the curing of PUR hot melt adhesive depends on the chemical reaction between ambient moisture and the -NCO groups in the adhesive, this step simulates a non-ideal temperature and humidity environment to verify whether the adhesive layer can still complete the basic cross-linking reaction and achieve sufficient peel strength under these process tolerances.

[0087] Comparative Examples 1-5: Comparative Example 1: Structural Defects Comparison Compared with Example 1, the difference is that only the traditional "three-in-one" fabric is prepared, that is, the third layer of functional sponge and the fourth layer of PTFE film are removed, and the first layer of nylon fabric, the second layer of PTFE film and the fifth layer of lining are directly bonded together, and all other parameters are the same.

[0088] Comparative Example 2: Coating Process Comparison Compared with Example 1, the difference is that in all bonding steps, the "continuous planar coating" process is used instead of the "dot-shaped roller transfer technology" of the present invention, so that the PUR adhesive coverage reaches 100%, while the remaining adhesive amounts are the same.

[0089] Comparative Example 3: Replacement of Core Adhesive Compared with Example 1, the difference is that: ordinary thermoplastic TPU hot melt adhesive film is used instead of the moisture-reactive PUR hot melt adhesive of the present invention, and the curing step is cancelled. Hot pressing at 150°C is used for lamination. All other aspects are the same.

[0090] Comparative Example 4: Functional Component Missing Compared with Example 1, the difference is that the third layer uses pure neoprene sponge without aerogel and graphene, while the rest of the preparation steps and composite process are the same.

[0091] Comparative Example 5: Comparison of Composite Processes Compared with Example 1, the difference is that a one-time five-layer synchronous pressure bonding is used instead of the step bonding (1+2+3 and 4+5) process of the present invention, while the other parameters are the same.

[0092] Test Examples 1-7: Test Example 1: Synergistic Effect Test of Functional Powders According to GB / T2918 standard, the third layer sponge samples prepared in Examples 1 to 3 and Comparative Example 4 (and an additional set of control sponge samples without silane coupling agent) were cut into standard test specimens of 150mm×150mm and conditioned in a constant temperature and humidity chamber at 23℃ and 50% relative humidity for 24 hours.

[0093] The thermal conductivity of the samples was determined using a steady-state heat flux meter method according to the GB / T10295 standard. The sample was clamped between a cold plate and a hot plate, with the hot plate temperature set to 35℃ and the cold plate temperature to 15℃. After the system reached thermal equilibrium, the heat flux density passing through the sample was recorded, and the thermal conductivity was calculated in W / (m·K). Three consecutive tests were performed, and the arithmetic mean was taken.

[0094] The volume resistivity of the sample was determined using a high-resistivity meter combined with a three-electrode testing system, according to the GB / T1410 standard. The sample was placed on the ring electrode test stage, and a DC voltage of 500V was applied for 60 seconds. The leakage current value was recorded and the volume resistivity was calculated in Ω·cm.

[0095] Electrostatic decay time was measured using an electrostatic decay tester according to GB / T12703.1 standard. A 5000V high-voltage corona discharge was applied to the sample surface to charge it. After the discharge stopped, the time required for the electrostatic voltage on the sample surface to decay from the peak value to 10% of the initial peak value was recorded, in seconds. Five tests were performed on a single sample at different locations, and the average value was taken.

[0096] Table 1. Test data of physical properties of functional sponges under different formulations and treatment conditions.

[0097] Figure 1 The distribution chart comparing the test data of thermal conductivity of various samples reflects the influence of different component additions and treatment methods on the thermal conduction resistance of the sponge matrix under constant temperature difference conditions. (Based on Table 1 and...) Figure 1 The thermal conductivity of the example groups was controlled between 0.0287 and 0.0415 W / (m·K), which is significantly lower than that of Comparative Example 4 (0.0683 W / (m·K) without any functional powders). In Example 2, the silica aerogel ratio was high, introducing a high proportion of nanoscale microporous gas layers into the matrix. The mean free path of gases in these mesoporous structures is limited, weakening convective heat transfer and gas-phase heat conduction. The solid-phase heat conduction path is prolonged due to the low density of the aerogel particles, forming a discontinuous heat-resistant phase within the rubber matrix, verifying the physical barrier mechanism of heat transfer in the composite material. The thermal conductivity of the unmodified control group was 0.0491 W / (m·K), higher than that of Example 1. This is because this group did not use a silane coupling agent to modify the surface of the functional powders, resulting in high surface energy on the powder surface, which led to agglomeration during the mixing and foaming process of the rubber matrix. Aggregation disrupts the original microporous foam structure, leading to uneven thickness or even rupture of the foam cell walls, causing the aerogel to lose its mesoporous thermal insulation properties in the dispersed state and resulting in an increase in the overall thermal conductivity.

[0098] Figure 2 The logarithmic (Log10) scale distribution of the volume resistivity test data of each sample reflects the difference in conductivity of the charge carrier transport pathway within the composite system. The lower the value, the more obvious the macroscopic conductivity of the material. Figure 3 The distribution chart comparing the electrostatic decay time of each sample reflects the rate at which the material surface dissipates static charge after high-voltage electrification. (See Table 1 for details.) Figure 2 and Figure 3 The data shows that the volume resistivity of the example group is below 10^7 Ω·cm, and the electrostatic decay time is within 2.0 s, meeting the antistatic material standard. Comparative Example 4 has a volume resistivity of 5.7 × 10^12 Ω·cm, exhibiting insulator characteristics, with charge easily accumulating on its surface. Figure 3 Because the measurement range exceeded the upper limit of the instrument, the electrostatic decay time was marked as greater than 12.0 seconds. In Example 3, the multilayer graphene nanosheets had a higher proportion, and the electrostatic decay time decreased to 0.31 s. Graphene has a high specific surface area and a two-dimensional conductive structure. When its addition amount in the rubber matrix exceeds the percolation threshold, a continuous electron transport network is formed between the nanosheet layers through physical contact or tunneling effect. Externally accumulated charges can be dissipated along this three-dimensional network. The volume resistivity of the unmodified control group reached 6.8 × 10^8 Ω·cm, and the electrostatic decay time was extended to 4.73 s. Untreated graphene is affected by strong van der Waals forces, resulting in layer stacking and recombination, which prevents uniform dispersion in the polymer matrix. Local agglomeration leads to the breakage of the electron transport network, and the system fails to form an effective macroscopic conductive pathway, thus failing to achieve rapid charge dissipation. Data from Example 1 shows that silane coupling agents improve the interfacial compatibility between inorganic powder and organic rubber macromolecular segments, inhibit phase separation, and enable silica aerogel and multilayer graphene to achieve dispersion equilibrium within a limited addition space, thus balancing the two mutually restrictive physical indicators of low thermal conductivity and low electrostatic decay time.

[0099] Test Example 2: PUR Moisture Curing Reaction Kinetics Test According to the GB / T2790 standard, at four time points—12h, 24h, 48h, and 72h—rectangular samples with a width of 50mm and a length of 200mm were cut from the original fabric rolls of Examples 1, 5, and Comparative Example 3 along the warp direction.

[0100] Manually peel a 50mm length of the first nylon fabric from the second PTFE film at one end of the sample to serve as the clamping end.

[0101] The sample is placed in a universal testing machine, and the two sides of the pre-peeled section are fixed in the upper and lower clamps of the testing machine.

[0102] Set the tensile speed of the testing machine to 100 mm / min, start the test, and record the force-displacement curves during the separation of the upper and lower clamps.

[0103] Force fluctuation data within 20 mm after the start of the test curve and within 10 mm before the end were discarded. The average force value of the effective peel interval in the middle was read as the peel strength of the sample. Five parallel samples of each group of fabrics were tested at each time point, and the arithmetic mean was calculated.

[0104] Table 2. Test data of 180° peel strength of various fabric samples under different curing times (unit: N / 50mm)

[0105] Figure 4 This is a line graph showing the 180° peel strength variation of various fabric samples under different curing times. The graph reflects the reaction kinetics of interlayer adhesion in composite fabrics over time under different temperature and humidity conditions and adhesive material systems. The horizontal axis represents the time points for the peel test (arranged at equal intervals), and the vertical axis represents the measured average peel strength value. In the graph, solid lines and solid dots represent Example 1, dashed lines and gray squares represent Example 5, and dotted lines and hollow triangles represent Comparative Example 3.

[0106] According to Table 2 and Figure 4 According to the data, the 180° peel strength of Example 1 showed an increasing trend from 12h to 48h, and then leveled off from 48h to 72h. In the early stages of testing, the PUR colloid remaining in the gaps between the fibers of the first layer of nylon fabric and the micropores of the PTFE film was in a physically cooling state, providing initial tack. After being placed in the curing chamber, water molecules diffused into the colloid layer, inducing an irreversible polyurethane crosslinking reaction of the isocyanate groups (-NCO) in the colloid. This process formed a three-dimensional network structure at the interface, and the interfacial bonding mechanism changed from a single physical-mechanical interlocking to a combination of physical anchoring and chemical bonding. After 48h, the data stabilized, indicating that the curing and crosslinking reaction was complete.

[0107] The data for Example 5 were lower than those for Example 1 at the 12h, 24h, and 48h nodes. The curing environment for Example 5 was set at 22°C and 50% relative humidity. The reduced water vapor concentration gradient weakened the penetration efficiency of moisture between polymer macromolecules, and the low temperature reduced the frequency of molecular thermal motion, decreasing the probability of collisions between -NCO groups and water molecules, thus inhibiting reaction kinetics and slowing the rate of peel strength increase. At 72h, the test value for Example 5 was 41.5 N / 50 mm, indicating that under low humidity and low temperature conditions, the crosslinking reaction process was prolonged, but with continued moisture penetration, a complete polyurethane crosslinking network could be established within the adhesive layer.

[0108] The peel strength test data of Comparative Example 3 did not show an increase over time, and a slight decrease was measured at the 48h and 72h nodes. Comparative Example 3 used ordinary thermoplastic TPU hot melt adhesive film as the bonding material, and the composite cooling process was the curing endpoint. The macromolecular chain segments only underwent physical entanglement at the interface. The system lacked moisture-reactive groups, and no chemical cross-linking occurred during the subsequent curing process. The residual thermal stress inside relaxed during the placement period, the polymer chain segments rearranged, and the locking force of the physical adhesive interface decreased, resulting in the peel strength data showing a decay characteristic over time. The data from Examples 1 and 5 verified the high-strength interfacial bonding ability of the PUR reaction system in the fabric-microporous film composite structure.

[0109] Test Example 3: Mechanical Interlocking Stability Test of Composite Interface According to GB / T7124 standard, test specimens of 25mm × 100mm were cut from the composite fabrics prepared in Examples 1, 4, and Comparative Example 5 along the warp, weft, and 45° diagonal directions, respectively. Each group of specimens was left to stand at 23℃ and 50%RH for 48 hours to eliminate residual curing stress.

[0110] Clamp the specimen at both ends onto the universal testing machine fixtures, with a clamping distance set to 50 mm. Apply a predetermined load to the specimen at a tensile speed of 10 mm / min until interface failure occurs. Record the maximum load at the moment of specimen failure and calculate the interfacial shear strength in MPa.

[0111] A multi-directional tensile die was used to apply a constant load equivalent to 30% of the specimen's fracture strength to each sample, which was maintained for 60 seconds before the pressure was released. A high-precision displacement sensor was used to record the residual deformation of the specimen in the warp, weft, and 45° directions, and the multi-directional tensile deformation rate was calculated to characterize the uniformity of stress distribution within the composite structure.

[0112] The morphology of the peeling interface was observed, the distribution of effective adhesive contact points per unit area was statistically analyzed, and micro-wrinkles or local debonding phenomena caused by internal stress accumulation were recorded.

[0113] Table 3. Test data on mechanical stability and multi-directional deformation of the composite interface

[0114] Figure 5This is a bar chart comparing the tensile deformation rates of various fabric samples under different stress directions. The chart reflects the uniformity and anisotropy of the internal stress distribution in the multilayer composite structure under tensile load. The horizontal axis represents different fabric samples, and the vertical axis represents the percentage of residual deformation after multi-directional tensile testing. Each sample corresponds to a set of three bars, filled from left to right with dark gray, medium gray, and light gray, representing the warp deformation rate, weft deformation rate, and 45° deformation rate, respectively. The smaller the height difference between the bars within a group, the better the consistency of material deformation in all directions and the more uniform the internal residual stress distribution.

[0115] According to the data in Table 3, the interfacial shear strength of Example 1 reached 1.42 MPa, which is higher than that of Comparative Example 5 (0.86 MPa). The step-by-step bonding process used in Example 1, after completing the lamination of the first fabric layer and the second film layer, allowed for a physical stress release time, enabling the PUR adhesive layer to fully wet the fiber surface and embed into the microporous structure during the initial stage of moisture curing, forming mechanical interlocking points. Comparative Example 5 used a multi-layer one-time lamination process. During synchronous winding, the differences in tensile modulus and thermal shrinkage of different materials led to stress mismatch between the layers. This internal stress was forcibly locked during the adhesive layer curing process, macroscopically manifesting as a decrease in shear strength.

[0116] Combined with Table 3 Figure 5 In the multi-directional tensile deformation rate test, Example 1 showed similar deformation in the warp (8.4%) and weft (8.1%) directions, with the increment in the 45° direction controlled within a reasonable range, demonstrating dimensional stability. Comparative Example 5 showed a deformation rate of 22.8% in the 45° direction. Figure 5 In Comparative Example 5, the light gray column at 45° exhibits an abnormally sudden increase in height, creating a significant difference in height compared to the longitudinal and latitudinal columns in the same group, demonstrating obvious anisotropy. This indicates severe internal stress accumulation and uneven stress distribution at the interface. The cumulative positive pressure generated by the overlapping of multiple layers of materials during the one-time lamination process obstructs the flow of the PUR colloid, creating stress concentration points at weak points. Under external tension, the accumulated internal stress induces premature failure of the microstructure, leading to excessive deformation of the material under oblique stress.

[0117] Example 1 showed an effective contact rate of 98.2%, with a regular interface morphology and no visible hollowness or wrinkling. Comparative Example 5 showed a contact rate of 84.7%, but exhibited large-area microscopic interface debonding. The step-by-step bonding process can reduce the accumulation of internal stress in multi-layer composite structures, ensure the integrity of the bonding between functional layers, and provide a guarantee for mechanical stability under subsequent complex working conditions.

[0118] Test Example 4: Thermal Protection Performance Test in Extreme Environments According to the evaporation thermal resistance and thermal resistance test method in GB / T11048 standard, the composite fabrics of Example 1, Comparative Example 1 and Comparative Example 4 were cut into 500mm×500mm square samples. The samples were placed in a standard laboratory environment with a temperature of 20℃ and a humidity of 65%RH for 24 hours for conditioning treatment.

[0119] Thermal resistance was tested using a flat-panel fabric thermal insulation tester. The surface temperature of the test plate (simulating human skin) was set to 35°C, and the temperature inside the ambient chamber was set to 20°C. After the heat flux on the test plate surface reached a steady state, the sample was placed on the test plate surface, and the electrical power consumption required to maintain the constant temperature of the test plate was measured and recorded. The thermal resistance value (Rct) of the sample was calculated and converted into the Clo value (Clo) according to the formula.

[0120] A low-temperature environment constant temperature maintenance time test was conducted. The sample was wrapped around the surface of a sealed metal simulated limb model equipped with an internal electric heating device and filled with constant-temperature water. The initial water temperature inside the model was set to 37.0℃.

[0121] The model covered with fabric was placed in a low-temperature environment test chamber at -20℃, and the air flow rate inside the test chamber was kept at 0.5m / s.

[0122] Turn on the high-precision multi-channel temperature recorder and collect the water temperature inside the model every 30 seconds. Set the test endpoint as the water temperature inside the model drops from 37.0℃ to 25.0℃, and record the total time of this process.

[0123] Repeat the above experiment, testing 3 parallel samples for each group of samples and taking the average value.

[0124] Table 4. Test data on the thermal protection performance of composite fabrics with different structures

[0125] Figure 6 This is a biaxial comparison chart of the thermal protection performance of composite fabrics with different structures. The chart visually reflects the differences in static thermal resistance and heat retention capacity of each sample group under extreme dynamic conditions. The horizontal axis represents the different fabric sample numbers. The left main vertical axis (corresponding to a light gray bar chart) represents the Clo value measured according to GB / T11048 standard, used to characterize the static thermal insulation performance of the fabric; the right secondary vertical axis (corresponding to a black line chart with solid dots) represents the total time required for the internal water temperature of the simulated limb model to drop to 25.0℃ in an extremely cold environment of -20℃, used to characterize the long-term heat flow barrier performance of the material under extreme conditions.

[0126] Combined with Table 4 Figure 6 According to the data, Example 1 achieved a Clo value of 3.12 Clo and maintained a constant temperature for 158.4 minutes in an extremely cold environment of -20°C. Figure 6In Example 1, the column height and the broken-line node are both at the highest positions, and all thermal protection indicators are significantly better than those of Comparative Example 1 and Comparative Example 4. Example 1 uses a five-layer composite structure that incorporates a CR rubber sponge layer containing nano-silica aerogel. The aerogel particles, acting as "heat insulation islands," are uniformly distributed within the rubber matrix, utilizing their extremely high porosity (>90%) and extremely small pore size (20-50 nm) to suppress air convection heat transfer and solid-state conduction heat transfer. With a total thickness (1.62 mm) similar to Comparative Example 4 (1.60 mm), Example 1 shows an increase in thermal resistance of approximately 51.7%. This indicates that its aerogel "heat insulation island" structure effectively shields against heat conduction while maintaining a similar thickness, demonstrating the core role of the aerogel-modified sponge layer in blocking heat conduction.

[0127] Comparative Example 1, a standard three-in-one structure, has a thickness of only 0.45 mm, a Clo value of only 1.18, and a temperature drop time of less than 43 minutes. This indicates that the traditional three-layer structure (outer fabric + membrane + lining fabric) cannot form an effective thermal barrier in low-temperature water or cold land operations due to the lack of physical buffering provided by the intermediate functional sponge layer and a sufficiently thick still air layer. The thermal resistance relies solely on the thermal conductivity of the fiber material itself. Even with the addition of a common rubber sponge layer in Comparative Example 4, increasing its total thickness to 1.60 mm, its temperature drop time is only 94.1 minutes. This is because the thermal conductivity of common rubber is higher than that of aerogel, allowing heat to be directly conducted away through the rubber matrix, lacking a microscopic thermal shielding mechanism.

[0128] The steady-state heat generation fluctuation value of Example 1 is only 0.24W, indicating that the structure has a strong ability to lock in internal heat after thermal equilibrium is established. This solution uses a five-layer integrated step-by-step bonding process to embed the aerogel functional layer between the PTFE microporous film and the nylon fabric, utilizing the interfacial heat reflection effect of materials with different moduli to reduce heat loss through radiation. Test data verifies the "heat island" mechanism of this solution, that is, through the synergistic effect of nanoscale aerogel and macroporous sponge, the composite fabric achieves high thermal protection performance under the premise of lightweight, making it suitable for long-term operation in extremely cold water environments.

[0129] Test Example 5: Dynamic Waterproof and Moisture-Permeability Balance Test According to the AATCC 127 hydrostatic pressure test standard and the ASTM E96 inverted cup method moisture permeability test standard, circular samples of specified sizes were cut from the fabrics of Examples 1-3, Comparative Examples 2 and 5, respectively. The samples were placed in an environment of 23°C and 50% relative humidity for 24 hours to acclimatize.

[0130] Fix the hydrostatic test specimen onto the fixture of the hydrostatic pressure tester, with the test surface facing the water surface. Apply water pressure continuously to the specimen at a rate of 60 mbar / min and observe the side of the specimen not in contact with water. When a third water droplet appears on the surface, record the hydrostatic pressure value at this point, in kPa.

[0131] Add a measured amount of distilled water to the moisture permeability test cup, cover the mouth of the test cup with the moisture permeability sample, and secure it with a sealing ring. Invert the test cup and fix it in a constant temperature and humidity chamber, setting the ambient temperature to 23℃, relative humidity to 50%, and wind speed to 0.5 m / s. Record the mass change of the test cup within the set time period and calculate the moisture permeability, using g / (m³). 2 •24h).

[0132] Simulated rainfall penetration tests were conducted. The sample was clamped on a dynamic waterproof flexural testing machine, with a known mass of absorbent filter paper attached to its back. The testing machine was started to subject the sample to continuous crumpling deformation, while the rain shower head was simultaneously turned on, with the spray intensity set to 10 L / (m²). 2 ·h).

[0133] The test lasts 120 minutes. If significant discoloration occurs on the filter paper surface during the test, record the time of penetration. After the test, remove the filter paper, weigh it, and calculate the water absorption. Five parallel samples are tested for each group of samples, and the arithmetic mean is taken.

[0134] Table 5 Dynamic Waterproof and Moisture-Permeability Balance Test Data

[0135] Figure 7 This is a biaxial comparison chart of the dynamic waterproof and breathable balance of various fabric samples. The chart visually presents the relationship between waterproofness and breathability under different coating processes and lamination procedures. The horizontal axis represents different fabric samples. The left main vertical axis (corresponding to dark gray bars) represents the hydrostatic pressure (kPa), used to characterize the fabric's ability to resist liquid water penetration; the right secondary vertical axis (corresponding to light gray bars) represents the breathable rate (g / (m³)). 2 •24h) is used to characterize the ability of a fabric to conduct human sweat.

[0136] Combined with Table 5 Figure 7 The data showed that the hydrostatic pressures of Examples 1, 2, and 3 reached 125.4 kPa, 118.7 kPa, and 131.2 kPa, respectively, while the moisture permeability remained between 6500 and 7150 g / (m³). 2 Within a 24-hour period. Figure 7In the example group, both the dark gray and light gray bars remained at a high level, exhibiting high waterproof and breathable properties. In the dynamic waterproof test, the example group showed no water seepage after 120 minutes of rubbing and rain exposure, with the filter paper water absorption controlled below 1.5g. This indicates that the step-by-step bonding process combined with PUR dot-matrix transfer technology forms a discrete adhesive array between the composite layers. While ensuring composite peel strength, the dot-matrix coating preserves the original microporous structure of the PTFE film in areas not covered by the adhesive. Water vapor emitted by the human body enters these unobstructed microporous channels through the gaps in the fabric fibers, achieving rapid diffusion of gaseous molecules. Simultaneously, the extremely low surface tension of the PTFE film, combined with its complete microporous diameter, effectively blocks the intrusion of external liquid moisture, achieving a balance between waterproof and breathable properties.

[0137] The extreme contrast in column height between the comparative examples indicates a severe performance imbalance in their physical structure or coating process. Comparative Example 2 exhibits a hydrostatic pressure of 145.6 kPa, but its moisture permeability is only 834 g / (m²). 2 ·24h), in Figure 7 The results show extremely high dark gray bars and extremely low light gray bars. Comparative Example 2 uses a planar coating process, where a continuous PUR film completely covers and seals the microporous network on the PTFE film surface. Water vapor molecules cannot undergo gas-phase physical mass transfer through the micropores; they can only be transferred through the free volume between dense polymer segments via dissolution-diffusion. The sharp increase in mass transfer resistance causes the material to lose its moisture-permeable function, resulting in sweat condensation during actual wear.

[0138] The moisture permeability of Comparative Example 5 was 5412 g / (m³). 2 (24h), but the hydrostatic pressure dropped to 42.8 kPa, in Figure 7 The light gray columns were extremely high, while the dark gray columns were extremely low. In a dynamic simulated rainfall permeability test, this sample failed to absorb water after 34 minutes, with a water absorption of 18.75g. Comparative Example 5 used a multi-layer one-time lamination process, and the difference in modulus of each layer of material caused stress accumulation during synchronous compression and winding. Under the alternating stress of the dynamic bending test, the internally locked residual stress and the external kneading force superimposed, causing microscopic tearing or interfacial delamination of the PTFE film in the stress concentration area. The destruction of the physical structure caused the film to lose its water barrier function, and liquid water directly permeated into the inner layer through the torn pores. The data from the example group verified the role of dot-matrix coating and stepwise lamination in maintaining the structural integrity and microporous permeability of the functional film.

[0139] Test Example 6: High and Low Temperature Cyclic and Mechanical Fatigue Stability Test According to ISO 7854 and GB / T 2790 standards, folding endurance test specimens of 50 mm × 100 mm and peel test specimens of 25 mm × 200 mm were cut from the composite fabrics prepared in Example 4 and Comparative Example 3, respectively. All specimens were left to stand for 24 hours at 23°C and 50% RH.

[0140] The folding resistance test specimens were clamped in a low-temperature folding tester, and the ambient temperature was lowered to -40℃ and pre-cooled at this temperature for 1 hour. The tester was set to run at a frequency of 100 times / minute, and the specimens were subjected to 50,000 consecutive folding deformation tests. After the test, the specimens were removed and allowed to recover at room temperature for 2 hours. The delamination and cracking at the interface were observed, and the residual hydrostatic pressure after folding was tested according to AATCC 127 standard.

[0141] The peeled samples were placed in a programmable temperature and humidity chamber for high and low temperature alternating treatment. A single cycle was set as follows: maintain at -40℃ for 2 hours, raise the temperature to 60℃ (90% relative humidity) within 30 minutes and maintain for 2 hours, then cool down to -40℃ within 30 minutes. A total of 20 cycles were run continuously.

[0142] After the alternating cycles were completed, the samples were removed and conditioned in a standard environment for 24 hours. The interfacial shear / peel strength after the cycles was tested using a universal testing machine at a tensile speed of 100 mm / min, and the retention rate relative to the initial strength was calculated. Five parallel samples were tested in each group, and the arithmetic mean was recorded.

[0143] Table 6. High and low temperature cycling and mechanical fatigue stability test data

[0144] Figure 8 This is a grouped bar chart comparing peel strength before and after high and low temperature cycling. The chart visually reflects the absolute difference in mechanical property retention of different adhesive systems after extreme thermodynamic damage. The horizontal axis represents different composite fabric samples, and the vertical axis represents the interfacial peel strength value (N / mm). Each sample in the chart corresponds to a set of two bars: the dark gray bar on the left represents the initial peel strength, and the light gray bar on the right represents the residual peel strength after 20 high and low temperature cycling cycles (-40℃ to 60℃).

[0145] Combined with Table 6 Figure 8 According to the data, the initial peel strength of Example 4 was 1.31 N / mm, and after 20 cycles of high and low temperature alternation from -40°C to 60°C, the peel strength was 1.14 N / mm, with a retention rate of 87.0%. Figure 8In Example 4, the height of the light gray column decreased only slightly compared to the dark gray column, indicating a high retention rate of its PUR crosslinking system. After 50,000 folding tests at -40°C, no significant blistering or breakage was observed at the interface of Example 4, and the residual hydrostatic pressure remained at 102.6 kPa. After coating and step-by-step bonding, the PUR hot melt adhesive used in Example 4 underwent an irreversible chemical crosslinking reaction with moisture in the air and polar groups on the fabric surface, forming a three-dimensional network of polyurethane-urea bonds. This chemical crosslinking network gives the adhesive layer stable temperature and heat resistance properties, preventing molecular chain disentanglement and slippage even at high temperature and humidity of 60°C. Simultaneously, the flexible segments in the PUR molecular structure maintain an elastic state above the glass transition temperature at -40°C, absorbing and dispersing the alternating stress generated by mechanical rubbing, preventing stress concentration at the interface between the adhesive layer and the film.

[0146] Comparative Example 3 used ordinary TPU hot melt adhesive, with an initial peel strength of 1.24 N / mm, but after high and low temperature alternating cycles, the peel strength decreased to 0.47 N / mm, with a retention rate of only 37.9%. Figure 8 In Comparative Example 3, the light gray column experienced a precipitous drop, indicating that its TPU physical cross-linking structure had suffered severe interfacial failure and irreversible damage under extreme temperature differences. After the low-temperature folding test, the sample of Comparative Example 3 showed local delamination and microcracks, and the residual hydrostatic pressure dropped significantly to 15.8 kPa. TPU hot melt adhesive mainly relies on the physical cross-linking structure formed by hydrogen bonds and physical van der Waals forces to provide adhesive strength. At 60°C, the hard segment microphase inside the TPU begins to soften, and the physical cross-linking points dissociate, leading to plastic flow and interfacial slippage in the adhesive layer, weakening the interlayer bonding force. When the temperature drops to -40°C, the movement of thermoplastic molecular chain segments is hindered, the free volume decreases, and the adhesive layer exhibits a significant tendency to become brittle. Under the cumulative deformation of 50,000 mechanical fatigue tests, the brittle adhesive layer fractures, and mechanical damage to the PTFE film is triggered along the interface, ultimately leading to the failure of the water-blocking performance of the composite fabric. The data from Example 4 verify the structural reliability of the PUR cross-linking system under extreme temperature differences and high-frequency mechanical stress.

[0147] Test Example 7: Washing Cycle and Antistatic Stability Test According to GB / T8629 standard, the composite fabrics of Example 1 and Comparative Example 4 were cut into samples of specified sizes. These samples were placed in a standard Type A washing machine and washed at 40°C using a standard washing program with standard detergent for 45 minutes per cycle. After washing, the samples were hung to dry.

[0148] The samples were removed after 0, 10, 30, and 50 washing cycles, respectively. They were then placed in a dry environment at 20°C and 35% relative humidity for 24 hours to acclimate them and eliminate the compensating effect of humidity on the electrostatic test.

[0149] According to GB / T12703.1, a triboelectric roller is used to standardize the triboelectric charging of the sample. The sample is then immersed in a Faraday cylinder, and the amount of charge carried is measured using an electrostatic charge meter to calculate the surface charge density (μC / m³). 2 ).

[0150] According to GB / T12703.4, the surface resistivity (Ω / sq) of a sample shall be tested using a high-resistivity meter under a specified DC voltage. The electrodes must be in close contact with the sample surface.

[0151] Five parallel samples were set up for each group, and the above test steps were repeated. The arithmetic mean was taken as the final result.

[0152] Table 7. Test data on the antistatic properties of composite fabrics after different washing cycles.

[0153] Figure 9 This is a biaxial line graph showing the effect of washing cycles on the antistatic stability of composite fabrics. The graph presents the evolution trend of the electrical properties of the samples during long-term washing. The horizontal axis represents the number of washes; the left main vertical axis uses a logarithmic scale (Log10) and corresponds to the surface resistivity line, reflecting the span of the material's conductivity levels; the right secondary vertical axis corresponds to the charge surface density line, reflecting the increase in charge accumulation capacity. In the graph, solid lines represent resistivity, and dashed lines represent charge surface density.

[0154] According to Table 7 and Figure 9 According to the data, in Example 1, after 50 washing cycles, its surface resistivity decreased from 4.6 × 10⁻⁶. 7 Ω / sq only increased to 8.2×10 7 Ω / sq, in Figure 9 The pattern is characterized by two extremely stable black lines (solid and dashed) on the left, consistently maintaining a level of 10. 7 The electrostatic dissipation range is orders of magnitude larger. The CR rubber sponge layer used in Example 1 incorporates graphene modified with a silane coupling agent during its preparation. The active functional groups on the graphene sheet surface form a covalently anchored structure with the rubber macromolecules during vulcanization. This in-situ bonding locks the two-dimensional conductive network within the polymer matrix, ensuring the long-term effectiveness of the electron transition channels even under mechanical shear stress during washing and the swelling effect of surfactants, without any detachment or physical loss of the conductive medium.

[0155] In contrast, all indicators in Comparative Example 4 showed a dramatic deterioration trend with increasing number of washes. Figure 9 In the diagram, the gray line representing Comparative Example 4 has an extremely steep slope, and its surface resistivity increases by four orders of magnitude after 50 washes, reaching 3.8 × 10⁻⁶. 12 Ω / sq, entering the insulator range; the surface charge density climbs to 7.34 μC / m 2 It exceeded 7.0 μC / m 2 The safety threshold is determined. The antistatic performance of Comparative Example 4 mainly relies on the physical adsorption agents on the fiber surface. These low-molecular-weight substances rapidly migrate and are lost into the washing liquid under hydrolysis and rubbing, causing the material surface to lose its water adsorption capacity and charge conduction pathway. Test data demonstrate that this solution, by constructing a conductive network through covalent bonding of graphene, has a significant advantage in ensuring long-term antistatic safety for personnel in special working environments.

Claims

1. A hydrological surveying suit fabric based on dotted PUR hot melt adhesive composite, characterized in that, From the outside in, the following are included: The first layer is a nylon fabric layer, the second layer is a PTFE microporous film layer, the third layer is a functional thin sponge layer, the fourth layer is a PTFE microporous film layer, and the fifth layer is a nylon warp-knitted fabric layer; Adjacent layers are bonded together by a dotted distribution of moisture-curing polyurethane hot melt adhesive. The third functional thin sponge layer is made from raw materials comprising the following parts by weight: Modified chloroprene rubber: 100 parts; Silica aerogel powder: 5-15 parts; Multilayer graphene nanosheets: 1-5 parts; Azodicarbonamide: 5.5 parts; Magnesium oxide: 3.5 parts; Zinc oxide: 4 parts; Naphthenic oil: 15 parts; Silane coupling agent: 1.5 parts; The silica aerogel powder and multilayer graphene nanosheets form an interpenetrating network inside the sponge. The low thermal conductivity of the aerogel and the rapid thermal conduction of graphene are used to synergistically regulate the dynamic thermal balance of the internal environment of the fabric and endow the fabric with antistatic function.

2. The hydrological survey clothing fabric based on dotted PUR hot melt adhesive composite according to claim 1, characterized in that, The preferred weight proportions of the raw materials are: 100 parts modified chloroprene rubber, 10 parts silica aerogel powder, 3 parts multilayer graphene nanosheets, 5.5 parts azodicarbonamide, 3.5 parts magnesium oxide, 4 parts zinc oxide, 15 parts naphthenic oil, and 1.5 parts silane coupling agent.

3. The hydrological survey clothing fabric based on dotted PUR hot melt adhesive composite according to claim 1, characterized in that, The average particle size of the silica aerogel powder is 60-80 nm. The average thickness of the multilayer graphene nanosheets is 6-7 nm.

4. The hydrological survey clothing fabric based on dotted PUR hot melt adhesive composite according to claim 1, characterized in that, The first nylon fabric layer has a weight of 180-220 g / m². 2 330D nylon 66 filament fabric; The thickness of the second and fourth PTFE microporous films is 15-25 μm, and the porosity is 75%-85%. The fifth layer has a weight of 35-45 g / m³. 2 20D nylon twill warp-knitted fabric.

5. The hydrological survey clothing fabric based on dotted PUR hot melt adhesive composite according to claim 1, characterized in that, The isocyanate group content of the PUR hot melt adhesive is 3.2%-3.8%; The density of the dotted PUR hot melt adhesive on the adhesive surface is 25-50 dots / cm. 2 The amount of adhesive applied is 10-25g / m². 2 .

6. A method for preparing hydrological survey clothing fabric based on dotted PUR hot melt adhesive composite, characterized in that, The application of the hydrological survey clothing fabric based on dotted PUR hot melt adhesive composite as described in any one of claims 1-5 includes the following steps: S1. Modified chloroprene rubber, functional powder paste dispersion and additives are mixed, sheeted and left to stand, then simultaneously foamed and cross-linked vulcanized in a mold, and finally cooled and slit to obtain a thin sponge with a thickness of 1.0 mm. S2. The first layer, the second layer and the functional thin sponge layer are bonded together by dot-coating PUR hot melt adhesive to obtain a three-in-one half product; S3. The fourth and fifth layers are bonded together by applying PUR hot melt adhesive in a dotted transfer pattern to obtain a two-in-one half product; S4. Apply PUR hot melt adhesive in dots to the sponge surface of the three-in-one half-finished product, press it together with the film surface of the two-in-one half-finished product, and roll it up to obtain a five-layer composite fabric roll. S5. Place the original roll in a constant temperature and humidity environment and let it stand for more than 48 hours to allow the adhesive layer to complete cross-linking and bridging.

7. The method for preparing hydrological survey clothing fabric based on dotted PUR hot melt adhesive composite according to claim 6, characterized in that, In S1, the processing method of the functional powder paste dispersion is as follows: Silica aerogel powder was mixed with multilayer graphene nanosheets, and a silane coupling agent and some naphthenic oil were sprayed on at 80°C. The mixture was then premixed into a paste by low-speed stirring.

8. The method for preparing hydrological survey clothing fabric based on dotted PUR hot melt adhesive composite according to claim 6, characterized in that, In S1, the process parameters for simultaneous foaming and cross-linking vulcanization are as follows: The mold closing pressure is 12.5 MPa, the heating temperature is 160℃-180℃, and the heat and pressure holding time is 8-15 minutes.

9. The method for preparing hydrological survey clothing fabric based on dotted PUR hot melt adhesive composite according to claim 6, characterized in that, In S2 to S4, the melting temperature of the PUR hot melt adhesive is controlled at 110-140℃; The pressure of the main pressure roller during the compounding process is set to 1.5-4.5 kg / cm. 2 The composite speed is 15-35 m / min.

10. The method for preparing hydrological survey clothing fabric based on dotted PUR hot melt adhesive composite according to claim 6, characterized in that, In S5, the specific environmental parameters for the ripening process are: Temperature 22℃-40℃, relative humidity 60%-90%; By regulating humidity, an irreversible curing reaction is induced in the -NCO groups in the adhesive layer, forming a three-dimensional network structure.

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