Self-adaptive buoyancy life jacket fabric

Abstract

The invention provides a self-adaptive buoyancy life jacket fabric which comprises a composite layer structure, and the composite layer structure comprises at least one base fabric layer, at least one core buoyancy unit layer and at least one outer protection layer; the core buoyancy unit layer is arranged between the base fabric layer and the external protection layer; the core buoyancy unit layer is composed of a plurality of microfluid buoyancy unit arrays which are mutually independent and have pressure response capability; each microfluid buoyancy unit comprises a microcavity, the cavity wall of the microcavity is made of an elastic high polymer material, and the interior of the microcavity is filled with inert gas with preset pressure. The self-adaptive deformation microfluid buoyancy unit array is introduced into the structure of the life jacket fabric, and the design of the pressure-responsive elastic material and an optional temperature self-adaptive enhancement mechanism are combined, so that continuous and stepless automatic adjustment of buoyancy in different water depth and water temperature environments is realized.

Description

Technical Field

[0001] This application belongs to the field of life jacket technology, specifically relating to an adaptive buoyancy life jacket fabric. Background Technology

[0002] With the continued development of the global economy and the increasing popularity and safety requirements of water activities and water rescue operations, the evolution of the performance and function of life jackets, as key equipment for protecting personal safety and enhancing the water activity experience, is particularly important. Traditional life jackets mainly achieve their basic protective function by providing fixed buoyancy, but they have not yet provided a comprehensive solution for the actual needs of users in different water environments, especially the balance between comfort and adaptive safety.

[0003] Currently, the mainstream life jacket technologies on the market can be mainly divided into two categories: First, padded life jackets, whose buoyancy primarily comes from the closed-cell foam material inside, such as polyvinyl chloride (PVC) foam, nitrile rubber (NBR) foam, or polyethylene (PE) foam. These materials, due to their low density and non-absorbency, provide stable buoyancy support. The advantages of this type of life jacket are its simple structure, low maintenance cost, and ability to provide immediate buoyancy in emergencies, effectively reducing the risk of drowning and playing a vital role in water safety. However, the buoyancy of this type of life jacket is fixed, determined by the volume and density of the filling material, and cannot be dynamically adjusted according to water conditions or the wearer's needs during use, resulting in inherent limitations when dealing with complex and changing water conditions. Second, inflatable life jackets, which typically use compressed gas cylinders (such as CO2 cylinders) to inflate instantaneously under a specific trigger mechanism, or are inflated via a manual inflation valve. The advantages of this type of life jacket are its compact size when not in use, not affecting the wearer's movement, and the ability to provide significant instantaneous buoyancy when needed. However, the buoyancy adjustment of inflatable life jackets is usually discrete (inflating or deflating) and mainly relies on external mechanical or manual operation, lacking continuity and adaptability. At the same time, there are certain requirements for the storage and replacement of gas cylinders, and there is a potential risk of accidental triggering or failure to trigger in a timely manner.

[0004] However, with the increasing diversification of water activities and people's higher pursuit of comfort, convenience, and intelligence in equipment, the inherent limitations of the aforementioned fixed buoyancy or discretely adjustable life jacket technologies are gradually becoming apparent. This is especially true when new demands arise for adaptive buoyancy adjustment to balance multiple performance indicators, where the drawbacks become particularly prominent. Specifically, the buoyancy design of traditional life jackets often forces a compromise between two seemingly contradictory needs: if a high buoyancy is designed to meet the high safety requirements in harsh sea conditions, its fixed bulk and excessive buoyancy will severely restrict the wearer's freedom of movement in calm waters, such as swimming, diving, or paddleboarding, leading to limited mobility, increased energy consumption, and significantly reduced comfort. It may even affect the wearer's posture control in the water due to excessive buoyancy. Conversely, if a low buoyancy is designed to improve comfort and flexibility in calm waters, the buoyancy provided may be far from sufficient to keep the wearer's head above water in emergencies such as sudden waves, strong currents, or loss of consciousness, thus creating serious safety hazards and even leading to drowning accidents.

[0005] Fundamentally, the buoyancy materials used in existing life jackets, whether solid foam or airbags, are fixed in their buoyancy value during manufacturing due to their physical mechanism. This buoyancy can only be altered to a limited and discontinuous degree through human intervention. This static or passive adjustment characteristic makes it impossible to adaptively respond to changes in the aquatic environment and the wearer's real-time needs, especially in complex scenarios requiring continuous, seamless, and dynamic buoyancy adjustment to balance comfort and safety. Furthermore, even attempts to achieve buoyancy adjustment by adding external mechanical or electronic systems (such as sensors, pumps, and valves) often introduce additional weight, volume, energy consumption, and system complexity, increasing potential points of failure and maintenance costs. Moreover, such solutions deviate from the fundamental requirement of achieving buoyancy adjustment through the fabric's own structure, failing to provide a fundamental, integrated solution at the material and fabric level. It is worth noting that the requirement for adaptive buoyancy adjustment of the "fabric structure" of life jackets means that it is necessary to break through the boundaries of traditional materials science and endow the fabric with the ability to sense and respond to changes in the external environment (such as water pressure, water flow speed, light intensity and even indirect factors such as temperature) at the microscopic level, thereby adjusting its macroscopic buoyancy characteristics. This is a deep technical bottleneck that existing technologies have failed to address. Summary of the Invention

[0006] This application provides an adaptive buoyancy life jacket fabric to solve the technical problem that existing life jackets cannot provide continuous, stepless adaptive buoyancy adjustment in different water environments while taking into account both comfort and safety.

[0007] To solve the above-mentioned technical problems, one technical solution adopted in this application is: an adaptive buoyancy life jacket fabric, including a composite layer structure, wherein the composite layer structure includes at least one base fabric layer, at least one core buoyancy unit layer and at least one outer protective layer.

[0008] The core buoyancy unit layer is positioned between the base fabric layer and the outer protective layer;

[0009] The core buoyancy unit layer consists of multiple independent microfluidic buoyancy unit arrays that are pressure responsive;

[0010] Each microfluidic buoyancy unit contains a microchamber, the walls of which are made of an elastic polymer material, and the interior of the microchamber is filled with an inert gas at a preset pressure.

[0011] Furthermore, the base fabric layer is woven from synthetic fiber material; the synthetic fiber material is at least one of high-density polyamide fiber or polyester fiber.

[0012] Furthermore, the surface of the base fabric layer is treated with a hydrophobic polymer.

[0013] Furthermore, the microcavities are all in the form of at least one of flat lens-shaped, ellipsoidal, or quasi-spherical structures; the major axis length of the microcavities is 1.5 mm to 4.0 mm, and the minor axis length is 0.8 mm to 2.5 mm; the cavity wall thickness of the microcavities is 50 μm to 150 μm.

[0014] Furthermore, the chamber walls of the microcavities are made of a TPU matrix.

[0015] Furthermore, the interior of the chamber wall is uniformly embedded with a microfiber network of ultra-high molecular weight polyethylene or aramid; the diameter of the microfiber ranges from 5μm to 20μm, and the volume fraction of the microfiber in the TPU matrix is ​​1% to 5%.

[0016] Furthermore, the inner wall of the microchamber is coated with a hydrophobic coating, which is composed of modified fluorosilane compounds or derivatives of modified fluorosilane compounds, and the thickness of the hydrophobic coating is 5nm-20nm.

[0017] Furthermore, the inert gas filling the microcavity is nitrogen, argon, or a mixture of nitrogen and argon; the preset pressure of the inert gas is 5 kPa to 20 kPa above the standard atmospheric pressure at sea level.

[0018] Furthermore, a predetermined proportion of temperature-responsive shape memory polymer or thermally responsive hydrogel is doped into the elastic polymer matrix of some or all of the microcavities; the doping proportion ranges from 1% to 5% of the total mass.

[0019] Furthermore, multiple microfluidic buoyancy units are integrated and arranged through flexible micro-connection channels or elastic thin film substrates to form a regular two-dimensional array; the width of the flexible micro-connection channels is 50μm-100μm.

[0020] The beneficial effects of this application are as follows: By introducing an adaptively deformable microfluidic buoyancy unit array into the structure of the life jacket fabric itself, and combining it with pressure-responsive elastic material design and optional temperature adaptive enhancement mechanism, this application realizes continuous and stepless automatic adjustment of buoyancy under different water depths and temperatures. This effectively solves the limitations of existing life jackets in terms of fixed or discrete buoyancy adjustment. Under the premise of ensuring water safety, it significantly improves the wearer's comfort, freedom of movement, and the product's intelligence level. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to specific embodiments.

[0022] Numerous specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways than those described herein, and therefore the invention is not limited to the specific embodiments disclosed in the following specification.

[0023] This application provides an adaptive buoyancy life jacket fabric, which is a composite layer structure comprising at least one base fabric layer, at least one core buoyancy unit layer, and at least one outer protective layer. The core buoyancy unit layer is disposed between the base fabric layer and the outer protective layer, and is composed of an array of multiple independent, pressure-responsive microfluidic buoyancy units. Each microfluidic buoyancy unit includes an internally sealed microchamber, the chamber wall of which is made of an elastic polymer material, and the interior of the microchamber is filled with a low-density inert gas at a preset pressure. The elastic properties of the chamber wall are precisely designed so that the volume of the microchamber can undergo continuous and reversible deformation in response to changes in external hydrostatic pressure, thereby achieving adaptive adjustment of the overall buoyancy of the fabric.

[0024] The base fabric layer, which serves as the structural skeleton of the entire fabric, is precisely woven from high-strength, low-absorbency synthetic fiber materials; the synthetic fiber materials are at least one of high-density polyamide fibers or polyester fibers.

[0025] In one specific embodiment, the base fabric layer is made of high-density polyamide 66 fiber with a unit area mass of 220 g / m², refined through a dense twill weave to ensure excellent tear resistance and dimensional stability under various stress conditions. To further enhance its performance in aquatic environments, the surface of the base fabric layer undergoes advanced hydrophobic treatments such as fluorocarbon polymer impregnation and thermosetting. This process ensures that the polymer molecular chains form a uniform, dense nanoscale hydrophobic film on the fiber surface, allowing the static water contact angle of the fabric to be stably maintained above 125 degrees, thereby minimizing water penetration and accumulation, while significantly accelerating the drying rate of the fabric and reducing discomfort caused by wet weight for the wearer. The thickness of the base fabric layer, after calendering, is typically controlled between 0.35 mm and 0.45 mm to provide sufficient mechanical support without significantly increasing the overall volume or weight of the fabric.

[0026] The core buoyancy unit layer is crucial for achieving adaptive buoyancy adjustment. It consists of a series of independent, pressure-responsive microfluidic buoyancy units arranged in a high-precision array. Each microfluidic buoyancy unit contains a completely sealed microcavity, the walls of which are constructed from a specially formulated and processed elastic polymer material. In one embodiment, the microcavity exhibits a flattened, lens-shaped structure designed to optimize its volume change efficiency and array integration under compressive deformation. In other embodiments, the microcavity may present an ellipsoidal or near-spherical structure.

[0027] Specifically, the major axis dimension of the lens-shaped microchamber is precisely controlled at 2.8 mm, the minor axis dimension at 1.5 mm, and the average thickness of its chamber wall is strictly limited to 90 μm. This geometric configuration and wall thickness ratio design minimizes the radial deformation of the microchamber under external pressure while maximizing the axial (thickness direction) deformation, thereby achieving efficient volume shrinkage while minimizing the gap between adjacent units and increasing the buoyancy density per unit area.

[0028] The matrix material for the chamber walls is a special thermoplastic polyurethane elastomer (TPU), with a Shore A hardness of 75A, exhibiting excellent biocompatibility, hydrolysis resistance, and fatigue resistance. This TPU material is synthesized through precisely controlled polymerization, ensuring a narrow molecular weight distribution and high crosslinking density, resulting in a tensile strength of up to 45 MPa, an elongation at break exceeding 600%, and an elastic recovery rate higher than 95% at room temperature.

[0029] To further enhance the mechanical properties of the chamber walls and achieve anisotropic control of the elastic modulus, a microfiber network of ultra-high molecular weight polyethylene (UHMWPE) or aramid (Kevlar) is uniformly doped into the TPU matrix. The diameter of the UHMWPE or Kevlar microfibers is controlled between 10 μm and 15 μm, and their volume fraction in the TPU matrix is ​​precisely set to 3%. After the microfibers are cast into a film from the TPU solution, they are aligned along a predetermined direction through a directional stretching process to form a reinforcing network. This network effectively restricts the expansion of the microchamber in unintended directions under pressure deformation, while guiding efficient and repeatable volume changes along the thickness direction. This anisotropic reinforcement mechanism not only improves the cycle life of the microchamber under long-term, high-frequency deformation but also significantly reduces the risk of structural damage under extreme pressure or accidental impact. Furthermore, to ensure no leakage of internal inert gas and no wetting of external moisture, the inner wall of the microchamber is further coated with a nanoscale hydrophobic / gas-repellent coating. The coating is prepared by chemical vapor deposition (CVD) using modified fluorosilane compounds, with the coating thickness precisely controlled between 12 nm and 18 nm. This ultrathin coating not only imparts superhydrophobic properties to the inner wall, resulting in a water contact angle exceeding 150 degrees, but also effectively suppresses the permeation rate of internal inert gases by reducing the interfacial energy between gas molecules and the chamber wall material, thereby ensuring the buoyancy stability of the microchamber during long-term use.

[0030] In one specific embodiment, to further enhance the fabric's adaptability to different water temperature environments, a specific proportion of temperature-responsive shape memory polymers (SMPs) are uniformly doped into the elastic polymer matrix of the chamber walls of some microcavities in the core buoyancy unit layer. The doped SMPs account for 2.5% of the total mass of the chamber walls. The phase transition temperature (T_t) of the SMPs is precisely designed and set at 18 degrees Celsius. When the ambient water temperature is below 18 degrees Celsius, the SMPs are in their glassy state, and the movement of their molecular chain segments is restricted, thereby increasing the effective stiffness of the chamber walls by approximately 20%. This increase in stiffness directly leads to a reduction in the volume shrinkage of the microcavities under the same external water pressure, thus enabling the fabric to maintain relatively higher buoyancy. This characteristic is crucial for water activities in cold waters, such as the Nordic coast, alpine lakes, or winter snowmelt environments, providing the wearer with additional buoyancy support to effectively combat hypothermia and provide stronger emergency rescue capabilities. Conversely, when the ambient water temperature exceeds 18 degrees Celsius, SMPs are in their elastic state, with increased mobility of molecular chain segments. This reduces the effective stiffness of the chamber walls, allowing the microchambers to undergo greater volume contraction under the same external water pressure, thereby reducing overall buoyancy. This reduction in buoyancy helps improve the wearer's comfort and freedom of movement in warm waters, such as tropical oceans or indoor swimming pools. By integrating this temperature-adaptive mechanism, this application further achieves intelligent optimization of buoyancy under different water temperature environments, building upon water pressure adaptation, and providing more comprehensive environmental adaptability.

[0031] In one implementation, multiple microfluidic buoyancy units are precisely integrated and arranged through flexible micro-connecting channels to form a regular two-dimensional array. The width of the micro-connecting channels is strictly controlled to 75 μm, and their material is the same as that of the chamber walls. This is designed to ensure that each microchamber maintains the stability of its relative position and independent deformation capability when the fabric is bent or twisted, preventing chain reactions or local stress concentration. The buoyancy unit array can be pre-fabricated into large-size films independently using high-precision microfluidic casting technology. This process is carried out in a Class 100 cleanroom environment to ensure a dust-free and sterile environment. A precisely proportioned mixture of TPU and UHMWPE fibers is injected into a pre-designed micromold, and its solidification process is precisely controlled by ultraviolet light or thermal curing to form a microchamber array with specific geometry and chamber wall thickness. The cured film is then sent to a specialized inflation and sealing station, where an inert gas (such as dry nitrogen) is precisely and synchronously injected using a microneedle array. The filling process is calibrated by a closed-loop control system equipped with a high-precision pressure sensor to ensure that the gas pressure in each microchamber is uniform and the fluctuation range is controlled within ±0.5KPa.

[0032] After filling, the microchamber is instantly and reliably sealed using ultrasonic welding or high-frequency hot pressing technology, ensuring no internal gas leakage and maintaining airtight stability for over ten years. Specific sealing parameters include: ultrasonic welding frequency of 40kHz, power of 200W, and welding time of 50 milliseconds; or high-frequency hot pressing temperature of 180 degrees Celsius, pressure of 1.5 MPa, and time of 0.8 seconds.

[0033] After the buoyancy unit film layer is prepared, it needs to be laminated and bonded to the base fabric layer and the outer protective layer in a multi-layer composite pressing process. The adhesive used is a specially formulated biocompatible, hydrolysis-resistant polyurethane-based adhesive with excellent adhesion, a solid content of 40%, and a viscosity of 1500 centipoise. The adhesive is uniformly applied to the interfaces of each layer using precision roller coating technology, ensuring a coating thickness of 30 μm to 50 μm without any bubbles or voids. The lamination and pressing process is carried out on a continuous lamination production line, where temperature, pressure, and time are precisely controlled.

[0034] Specifically, the hot-pressing temperature is set at 100 degrees Celsius, the pressing pressure at 1.2 MPa, and the pressing time at 60 seconds. These conditions aim to activate the adhesive and promote its full cross-linking with each layer of material, forming a strong, non-delaminating interface bond with good flexibility. The outer protective layer consists of a modified polyurethane film with chlorine resistance, UV resistance, and excellent abrasion resistance, with a thickness ranging from 0.15 mm. This protective layer is modified with special UV-resistant additives, blocking over 98% of UV-A and UV-B radiation, significantly extending the fabric's lifespan in outdoor environments. The main function of the outer protective layer is to provide comprehensive physical protection for the internal buoyancy unit layer, protecting it from external mechanical damage (such as scratches, abrasions, and punctures), chemical corrosion (such as seawater, chlorine, and oil), and material degradation caused by UV radiation. Furthermore, the surface of the outer protective layer is further designed with micron-level textured surfaces using molding technology. This texture not only reduces fluid resistance when the fabric moves in water, optimizing hydrodynamic performance, but also utilizes the lotus leaf effect to enhance the fabric's stain resistance and ease of cleaning.

[0035] In a specific application scenario, the life jacket fabric of this application can be further integrated with a micro-sensor unit array. These sensor units do not directly participate in buoyancy regulation but can provide real-time monitoring data on fabric deformation or environmental parameters. The sensor unit array includes piezoresistive sensors and fiber Bragg grating (FBG) sensors, which are integrated in a flexible array in the interlayer between the base fabric layer and the core buoyancy unit layer. The piezoresistive sensors indirectly infer the current water depth or external hydrostatic pressure by monitoring the local strain changes caused by micro-cavity deformation; while the FBG sensors utilize their sensitivity to pressure and temperature to provide more accurate environmental parameter data and can be used to evaluate the real-time feedback of buoyancy regulation effects. The sensor unit array is integrated with an ultra-low power microcontroller (MCU) using a highly integrated ARM Cortex-M0+ core and integrating a low-power Bluetooth (BLE 5.0) wireless communication module. This module can transmit monitoring data to the wearer's smartphone or professional monitoring equipment for analysis with extremely low power consumption, thereby providing real-time feedback information on key parameters such as the wearer's buoyancy status, water depth, and water temperature. The MCU, wireless communication module, and sensor unit are all integrated using a flexible circuit board with a thickness of only 0.2 mm, possessing excellent bending and twisting properties to ensure that the overall flexibility of the fabric remains unaffected. The entire system is powered by a micro-thin-film lithium-ion battery with a capacity of 50 mAh, supporting continuous operation for over 72 hours. Furthermore, energy harvesting modules can be selectively integrated into the fabric, such as piezoelectric power generation modules based on flexible piezoelectric materials (e.g., PVDF) or thermoelectric power generation modules based on thermoelectric materials (e.g., Bi₂Te₃). These energy harvesting modules can convert the mechanical energy generated by the wearer's movement or the temperature difference in the aquatic environment into electrical energy to recharge the thin-film battery, thus ensuring that the entire fabric system has high integration, self-powered capability, and low maintenance costs, requiring no additional external power supply or complex wiring.

[0036] As a highly optimized implementation of this application, the density, size, or elasticity of the buoyancy units in the life jacket fabric can be customized during the manufacturing process according to the functional requirements of different areas of the life jacket. For example, in the core torso area of ​​the life jacket, especially the chest and back, to provide maximum buoyancy support and keep the wearer's mouth and nose above the water surface, higher density (15 microchambers per square centimeter) or larger size (4.0 mm major axis, 2.5 mm minor axis) microchambers can be used, and the Shore hardness of the chamber walls can be selectively increased to 80A to provide stronger buoyancy while ensuring safety. In limb joint areas, such as the elbows, knees, and armpits, to maximize the freedom of movement and comfort of the joints, smaller size (1.5 mm major axis, 0.8 mm minor axis) or lower density (5 microchambers per square centimeter) microchambers can be used, or even no buoyancy units can be placed in these areas. In areas such as the neck or head support, special designs can be used to ensure that buoyancy is quickly provided and the head is supported when the fabric is wet. This regionalized buoyancy distribution design is achieved by precisely controlling the arrangement density, size, and chamber wall structure parameters of the buoyancy units in the fabric, thereby further optimizing the overall performance of the life vest. This allows it to maintain high safety while significantly improving the wearer's mobility, comfort, and compliance with long-term wear.

[0037] To further illustrate the technical effects of this application, an embodiment and a comparative example are provided below for comparison.

[0038] Example 1: Using the adaptive buoyancy life jacket fabric of this application

[0039] In a specific production batch, an adjustable buoyancy life jacket fabric conforming to this application was produced. The base fabric layer of this fabric uses a 220 g / m² material. 2 The high-density polyamide 66 twill fabric has a hydrophobic surface treated with fluorocarbon polymer, resulting in a static water contact angle of 128°. The core buoyancy unit layer comprises flat, lens-shaped microcavities with a major axis of 2.8 mm, a minor axis of 1.5 mm, and a wall thickness of 90 μm. The chamber walls are made of TPU with a Shore A hardness of 75A, internally doped with 3% by volume UHMWPE microfibers (12 μm in diameter). The microcavities are filled with 99.999% pure dry nitrogen gas at an initial inflation pressure of 113.3 kPa. The inner walls are coated with a 15 nm modified fluorosilane coating. The chamber walls are doped with 2.5% SMPs with a phase transition temperature of 18°C. The core buoyancy unit layer is fabricated using microfluidic casting, microneedle inflation, and ultrasonic welding sealing. The layers are bonded together using a polyurethane-based adhesive via hot pressing at 100°C, 1.2 MPa, and 60 seconds. The outer protective layer is a 0.15mm thick modified polyurethane film with a micron-level textured surface. The fabric integrates piezoresistive and FBG sensor arrays, transmitting data via a BLE module.

[0040] Comparative Example 1: Buoyancy fabric without nano-level hydrophobic / air-repellent coating

[0041] To highlight the importance of the nanoscale hydrophobic / gas-repellent coating in this invention, a fabric with essentially the same technical parameters as in Example 1 was prepared, except that the microcavity was not coated with the nanoscale hydrophobic / gas-repellent coating. All other materials, dimensions, inflation pressure, manufacturing process, and composite structure remained consistent with Example 1 to ensure the rigor of the comparison.

[0042] Several performance tests were conducted on the life jacket fabric samples prepared in Example 1 and Comparative Example 1, including buoyancy adjustment capability at different water depths, buoyancy performance at different water temperatures, internal gas retention rate, and long-term cycle life. The test methods are as follows:

[0043] Buoyancy adjustment capability test: The fabric sample is fixed to a precision sensor and gradually immersed in a depth-adjustable water tank. The buoyancy values ​​of the fabric at water depths of 0m, 1m, 3m, and 5m are recorded, and the buoyancy adjustment range is calculated.

[0044] Gas retention rate test: The fabric sample is placed in a standard atmospheric pressure and 25°C environment for 120 hours, its buoyancy value is measured, and the buoyancy drop rate is calculated to assess the gas leakage.

[0045] Cyclic life test: Fabric samples were repeatedly submerged and raised in water at depths of 1m to 5m to simulate the repeated pressure and depressurization processes experienced by life jackets in actual use. The buoyancy performance and structural integrity of the fabric were checked after every 1000 cycles, until the buoyancy decreased by more than 10% or visible structural damage appeared. Specific comparative results are shown in Table 1.

[0046] Table 1 shows a comparison of the test results between the examples and the comparative examples.

[0047]

[0048]

[0049] As shown in Table 1, the adjustable buoyancy life jacket fabric prepared in Example 1 significantly outperforms Comparative Example 1 in several key performance indicators. Although the initial buoyancy performance is similar in the surface and shallow water areas (0-1 meter), in the deep water area (3-5 meters), Example 1 exhibits a wider and more precise buoyancy adjustment range, with a buoyancy adjustment range of 38.6% in the 0-5 meter range, higher than the 34.1% of Comparative Example 1. This indicates that although the nanoscale inner wall coating mainly functions to retain gas, its influence on the microscopic deformation characteristics of the chamber wall, combined with the overall elastic design, also indirectly optimizes the volume shrinkage efficiency in the deep water area. More importantly, in terms of gas retention rate, Example 1 can still maintain 98.5% of the initial buoyancy after 120 hours, while the buoyancy of Comparative Example 1 decreased by a staggering 15%. This directly proves the key role of the nanoscale hydrophobic / gas-repellent coating in effectively preventing the internal inert gas from permeating outward. The internal coating significantly extends the lifespan and buoyancy stability of the buoyancy unit by reducing the permeability coefficient at the interface between gas molecules and the chamber wall material. Furthermore, regarding cycle life, Example 1 withstood over 10,000 cycles with a buoyancy decrease of less than 10%, while Comparative Example 1 showed a significant buoyancy decrease after only 3,500 cycles. This further confirms that the internal coating not only effectively prevents gas permeation, but its strengthening effect on the chamber wall material and optimization of gas molecule behavior also contribute to improving the fatigue resistance of the chamber wall under long-term dynamic deformation. In terms of water temperature adaptability, Example 1, due to its integrated temperature-responsive SMPs, maintained a buoyancy of 175N at 10°C, higher than the 165N at room temperature, while the buoyancy decreased to 158N at 30°C. This fully demonstrates its ability to intelligently adjust buoyancy to meet different needs under varying water temperatures. Comparative Example 1, lacking this temperature adaptive mechanism, had buoyancy largely unaffected by water temperature and could not provide this additional function.

[0050] In summary, this application achieves continuous, stepless, and automatic adjustment of buoyancy under different water depths and temperatures by introducing an adaptively deformable microfluidic buoyancy unit array into the structure of the life jacket fabric, combined with a pressure-responsive elastic material design, a nanoscale inner wall coating, and an optional temperature-adaptive enhancement mechanism. This invention effectively solves the limitations of existing life jackets in terms of fixed or discrete buoyancy adjustment, significantly improving wearer comfort, freedom of movement, and the product's intelligence level while ensuring water safety.

[0051] The life jacket fabric of this invention features high integration, lightweight, reliability, durability, and low maintenance costs, providing an innovative safety solution for water sports, rescue, and other fields.

[0052] The above description is merely an embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A life jacket fabric with adaptive buoyancy, characterized in that, It includes a composite layer structure, which comprises at least one base fabric layer, at least one core buoyancy unit layer and at least one outer protective layer. The core buoyancy unit layer is disposed between the base fabric layer and the outer protective layer; The core buoyancy unit layer is composed of multiple independent microfluidic buoyancy unit arrays that are pressure responsive. Each of the microfluidic buoyancy units includes a microchamber, the walls of which are made of an elastic polymer material, and the interior of which is filled with an inert gas at a preset pressure.

2. The adaptive buoyancy life jacket fabric according to claim 1, characterized in that, The base fabric layer is woven from synthetic fiber material; the synthetic fiber material is at least one of high-density polyamide fiber or polyester fiber.

3. The adaptive buoyancy life jacket fabric according to claim 2, characterized in that, The surface of the base fabric layer is hydrophobically treated with a fluorocarbon polymer.

4. The adaptive buoyancy life jacket fabric according to claim 1, characterized in that, The microcavities are all in the form of at least one of the following: flat lens shape, ellipsoidal shape, or quasi-spherical shape; the major axis of the microcavity is 1.5 mm to 4.0 mm, and the minor axis is 0.8 mm to 2.5 mm; the wall thickness of the microcavity is 50 μm to 150 μm.

5. The adaptive buoyancy life jacket fabric according to claim 4, characterized in that, The walls of the microchambers are made of TPU matrix.

6. The adaptive buoyancy life jacket fabric according to claim 5, characterized in that, The chamber wall is uniformly embedded with a microfiber network of ultra-high molecular weight polyethylene or aramid; the diameter of the microfiber ranges from 5μm to 20μm, and the volume fraction of the microfiber in the TPU matrix is ​​1% to 5%.

7. The adaptive buoyancy life jacket fabric according to claim 6, characterized in that, The inner wall of the microcavity is coated with a hydrophobic / gas-repellent coating, which is composed of a modified fluorosilane compound or a derivative thereof, and the thickness of the hydrophobic / gas-repellent coating is 5nm-20nm.

8. The adaptive buoyancy life jacket fabric according to claim 6, characterized in that, The inert gas filling the microcavity is nitrogen, argon, or a mixture of nitrogen and argon; the preset pressure of the inert gas is 5 kPa to 20 kPa above the standard atmospheric pressure at sea level.

9. The adaptive buoyancy life jacket fabric according to claim 6, characterized in that, Some or all of the microcavities are doped with a predetermined proportion of temperature-responsive shape memory polymer or thermally responsive hydrogel in their elastic polymer matrix; the doping proportion ranges from 1% to 5% of the total mass.

10. The adaptive buoyancy life jacket fabric according to claim 1, characterized in that, Multiple microfluidic buoyancy units are integrated and arranged through flexible micro-connection channels or elastic thin film substrates to form a regular two-dimensional array; the width of the flexible micro-connection channels is 50μm-100μm.

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