Waterproof profiled adhesive tape and preparation method thereof

Abstract

The present application provides a waterproof profiled adhesive tape, which comprises a substrate layer and an adhesive layer, the edge of the substrate layer is not linear but curved, the adhesive layer comprises a continuous hydrophobic matrix phase and a hydrophilic skeleton phase, the continuous hydrophobic matrix phase is composed of a hydrophobic mixture A, forming a main continuous phase of the adhesive tape, providing adhesion and basic water resistance; the hydrophilic skeleton phase is composed of an electrospun membrane loaded with superabsorbent microparticles, which is dispersed in the hydrophobic matrix phase; wherein the hydrophilic skeleton phase has water-swelling characteristics, maintains the skeleton form in the dry state, and undergoes anisotropic or isotropic volume expansion in the water state, which produces a compression densification effect on the surrounding hydrophobic matrix phase, and at the same time, the skeleton itself swells to fill the interfacial gap, forming a water molecule diffusion blocking mechanism.

Description

Technical Field

[0001] This invention relates to the field of polymer material processing and molding and functional sealing technology, specifically to a waterproof irregularly shaped tape and its preparation method. Background Technology

[0002] In the current landscape of rapid global industrial technological development, product design is evolving towards lightweighting, integration, flexibility, and precision. This trend has directly led to a fundamental transformation in the morphology of connection interfaces, edge seams, and covering structures in end products: from traditional planar or simple right-angled structures to complex non-linear geometric forms such as curved surfaces, arcs, and irregular shapes. In such complex and irregular interfaces, sealing materials must possess extremely high surface compliance and interfacial bonding strength to ensure long-term reliability under dynamic stress, temperature changes, and humid and hot environments.

[0003] However, existing technological solutions for waterproofing and sealing still have significant shortcomings. Currently, most mainstream waterproof tapes and sealants on the market focus on optimizing a single matrix material or strengthening the physical barrier. For example, pressure-sensitive adhesives (such as acrylates, silicone rubber, and polyurethane) are commonly used to achieve barrier properties through physical bonding, or expanded graphite and inorganic fillers are used for physical filling. However, these solutions often reveal inherent flaws when dealing with irregular interfaces: First, the material itself lacks the ability to actively repair micro-cracks. Once thermal expansion and contraction or external forces cause micro-cracks at the interface, water molecules can quickly penetrate through capillary action, forming irreversible leakage channels. Second, the adhesive strength and cohesive strength of a single material often contradict each other. Increasing thickness to achieve high adhesive strength can lead to decreased flexibility, causing stress concentration at curved surfaces and further increasing the risk of seal failure.

[0004] Furthermore, in the field of composite sealing technology involving hydrophilic functional materials, existing technologies typically employ simple physical blending to directly disperse hydrophilic polymer particles within a hydrophobic matrix. While this structure maintains its basic form in a dry environment, upon contact with moisture, the hydrophilic particles blended within the matrix undergo rapid and intense swelling. This disordered volume expansion not only disrupts the original continuous phase structure of the matrix, leading to blistering, delamination, and loss of adhesion within the tape, but also transforms the swollen gel into a "sponge channel" for water molecule migration, failing to provide any blocking effect and instead accelerating overall water absorption and aging. Moreover, for technologies employing chemical grafting modification, the preparation process is complex and costly, and the distribution density of hydrophilic groups is difficult to control, easily causing localized overhydration leading to substrate corrosion or long-term immersion failure.

[0005] Therefore, overcoming the dual technical bottleneck of poor dynamic response of tape when exposed to water and developing a highly waterproof sealing material has become a technical challenge that urgently needs to be overcome in this industry. Summary of the Invention

[0006] The technical problem to be solved: The purpose of this invention is to provide a smart composite sealing material with stable structure that can actively expand upon contact with water, generate a compression and densification effect on the surrounding matrix, and fill the gaps.

[0007] Technical solution: A waterproof irregularly shaped adhesive tape, comprising a substrate layer and an adhesive layer, wherein the edge of the substrate layer is non-linear but curved, and the adhesive layer comprises a continuous hydrophobic matrix phase and a hydrophilic skeleton phase. The continuous hydrophobic matrix phase is composed of a hydrophobic mixture A, forming the main continuous phase of the tape, providing adhesion and basic water resistance; the hydrophilic skeleton phase is composed of an electrospun membrane loaded with superabsorbent micron particles, wherein the hydrophilic skeleton is dispersed in the hydrophobic matrix phase. The hydrophilic framework phase has the property of swelling when exposed to water. It maintains its framework shape in a dry state and undergoes anisotropic or isotropic volume expansion when exposed to water, which compresses and densifies the surrounding hydrophobic matrix phase. At the same time, the framework itself swells and fills the interfacial gaps, forming a water molecule diffusion blocking mechanism.

[0008] Preferably, the hydrophobic mixture A comprises the following components by weight: Vinyl-terminated polydimethylsiloxane: 100 parts MQ silicone tackifier: 20-50 parts Hydrogen-containing silicone oil crosslinking agent: 1-5 parts Platinum catalyst: 5~50 ppm (based on the weight of vinyl-terminated polydimethylsiloxane) Hydrophobic fumed silica: 0~10 parts Preferably, the method for preparing the hydrophilic skeleton includes the following steps: S11. Acrylamide, N'N-dimethylbisacrylamide and ammonium persulfate are added to water and mixed evenly to obtain an aqueous phase; S12. Dissolve Span-40 in cyclohexane to obtain an oil phase; S13. Add the aqueous phase dropwise to the oil phase while stirring. Stir at a water bath temperature of 45-50°C at a stirring rate of 300-350 r / min. After the reaction is complete, cool down, filter and dry to obtain micron-sized water-absorbing particles. S14. Dissolve cellulose acetate powder in trifluoroacetic acid and stir at room temperature until a homogeneous solution is formed; S15. Add the micron-sized water-absorbing particles to the solution prepared in S14, stir and mix evenly to obtain the spinning solution; S16. Electrospin the spinning solution, with the distance from the spinneret to the collecting plate being 10~12cm, the voltage being 12~15 kV, and the spinning speed being 0.25~0.4mL / h, to obtain a hydrophilic skeleton.

[0009] Preferably, the mass ratio of acrylamide, N'N-dimethylbisacrylamide, ammonium persulfate and water in S11 is 5:0.04~0.05:0.07~0.085:50.

[0010] Preferably, the mass ratio of Span-40 to cyclohexane in S12 is 1~1.5:100.

[0011] Preferably, the ratio of oil phase to water phase in S13 is 2~3:1.

[0012] Preferably, the mass fraction of micron-sized water-absorbing particles in the spinning solution in S15 is 10~20wt%.

[0013] Preferably, the porosity of the hydrophilic framework is greater than 80%.

[0014] The above-mentioned method for preparing waterproof shaped tape includes the following steps: S1. Cut the substrate into curved edges; S2. A hydrophilic skeleton is stacked on the surface of the cut substrate layer; S2. Coat the hydrophobic mixture onto the side of the substrate layer containing the hydrophilic skeleton, and cure it after scraping to obtain a waterproof shaped tape.

[0015] Beneficial effects: This invention has the following advantages: In this invention, the tape is designed with a curved, irregular structure. The curved edges can change the direction of water flow, reduce the scouring force of water on the tape surface and edges, reduce water retention and penetration at the tape-sealing interface, and further reduce the possibility of water penetrating into the tape. At the same time, the synergistic effect of the adhesive layer, the substrate layer, and the hydrophilic skeleton phase further improves the adhesion between the tape and the irregular interface, reduces the generation of interface gaps, and structurally lays a double foundation for highly efficient waterproofing. In this invention, the continuous hydrophobic matrix phase in the adhesive layer is composed of a specific ratio of vinyl-terminated polydimethylsiloxane, MQ silicone resin tackifier, and other components. It possesses excellent hydrophobicity and structural stability, forming a dense basic water-blocking barrier that effectively prevents the initial penetration of water molecules. The hydrophilic skeleton phase dispersed in the hydrophobic matrix phase is composed of an electrospun film loaded with superabsorbent micron particles. In the dry state, it can maintain the complete skeleton morphology without destroying the continuity of the hydrophobic matrix phase. When it comes into contact with water, it undergoes controllable volume expansion. On the one hand, it compresses and densifies the surrounding hydrophobic matrix phase, further enhancing the water-blocking ability of the hydrophobic barrier. On the other hand, after swelling, it can precisely fill the microcracks and gaps at the interface, forming a dynamic water molecule diffusion blocking mechanism, achieving active sealing, and significantly improving the waterproof reliability and long-term effectiveness of the tape.

[0016] This invention produces micron-sized water-absorbing particles through a reverse emulsion polymerization process. These particles have uniform particle size and stable water absorption performance, and the preparation process is mild and controllable, allowing for precise control of particle size and water absorption ratio. Subsequently, the micron-sized water-absorbing particles are dispersed in a cellulose acetate spinning solution for electrospinning. Trifluoroacetic acid is used as a solvent, which effectively avoids the problems of premature water absorption, swelling, and clumping of the superabsorbent particles, ensuring that the particles are uniformly dispersed in the spinning solution. The resulting electrospun film has a continuous fiber skeleton structure, which can stably load the superabsorbent particles and has good flexibility and hydrophilicity. It maintains its morphology in the dry state and can achieve rapid and uniform swelling upon contact with water, playing a role in extrusion densification and gap filling. Detailed Implementation

[0017] The present invention will be further described below with reference to embodiments. These embodiments are illustrative of the present invention, but the present invention is not limited to these embodiments: Cellulose acetate (Nantong Acetate Fiber Co., Ltd., degree of deacetylation 2.5, degree of polymerization 200) Example 1

[0018] A waterproof shaped tape includes a substrate layer and an adhesive layer. The edge of the substrate layer is not straight but curved. The adhesive layer includes a continuous hydrophobic matrix phase and a hydrophilic skeleton phase. The continuous hydrophobic matrix phase is composed of a hydrophobic mixture A, forming the main continuous phase of the tape and providing adhesion and basic water resistance. The hydrophilic skeleton phase is composed of an electrospun membrane loaded with superabsorbent micron particles, and the hydrophilic skeleton is dispersed in the hydrophobic matrix phase. The above-mentioned method for preparing waterproof shaped tape includes the following steps: S1. Cut the substrate into curved edges; S2. A hydrophilic skeleton is stacked on the surface of the cut substrate layer; S2. Apply hydrophobic mixture A to the side of the substrate layer containing the hydrophilic skeleton, wherein the hydrophobic mixture A is 65 g / m². 2 After being scraped and cured, waterproof shaped tape is obtained; The hydrophobic mixture A comprises the following components by weight: Vinyl-terminated polydimethylsiloxane: 100 parts; MQ silicone resin tackifier: 20 parts; hydrogen-containing silicone oil crosslinking agent: 1 part; platinum catalyst: 50 ppm (based on the weight of vinyl-terminated polydimethylsiloxane); hydrophobic fumed silica: 8 parts; The method for preparing the hydrophilic skeleton includes the following steps: S11. Acrylamide, N'N-dimethylbisacrylamide and ammonium persulfate are added to water in a mass ratio of 5:0.04:0.07:50. The mixture is stirred until a homogeneous aqueous phase is obtained. S12. Dissolve Span-40 in cyclohexane at a mass ratio of 1.5:100 to obtain an oil phase; S13. Add the aqueous phase dropwise to the oil phase, with a ratio of oil phase to water phase of 2:1. Stir while adding the aqueous phase, and stir in a 50°C water bath at a stirring rate of 350 r / min. After the reaction is complete, cool down, filter and dry to obtain micron water-absorbing particles. S14. Dissolve cellulose acetate powder in trifluoroacetic acid and stir at room temperature until a homogeneous solution is formed; S15. Add the micron-sized water-absorbing particles to the solution prepared in S14, stir and mix evenly to obtain a spinning solution, wherein the mass fraction of the micron-sized water-absorbing particles in the spinning solution is 10 wt%. S16. Electrospin the spinning solution, with the distance from the spinneret to the collecting plate being 10-12 cm, the voltage being 15 kV, and the spinning speed being 0.4 mL / h, to obtain a hydrophilic skeleton with a porosity of 85.5%.

[0019] Example 2

[0020] A waterproof shaped tape includes a substrate layer and an adhesive layer. The edge of the substrate layer is not straight but curved. The adhesive layer includes a continuous hydrophobic matrix phase and a hydrophilic skeleton phase. The continuous hydrophobic matrix phase is composed of a hydrophobic mixture A, forming the main continuous phase of the tape and providing adhesion and basic water resistance. The hydrophilic skeleton phase is composed of an electrospun membrane loaded with superabsorbent micron particles, and the hydrophilic skeleton is dispersed in the hydrophobic matrix phase. The above-mentioned method for preparing waterproof shaped tape includes the following steps: S1. Cut the substrate into curved edges; S2. A hydrophilic skeleton is stacked on the surface of the cut substrate layer; S2. Apply hydrophobic mixture A to the side of the substrate layer containing the hydrophilic skeleton, wherein the hydrophobic mixture A is 65 g / m². 2 After being scraped and cured, waterproof shaped tape is obtained; The hydrophobic mixture A comprises the following components by weight: Vinyl-terminated polydimethylsiloxane: 100 parts; MQ silicone resin tackifier: 20 parts; hydrogen-containing silicone oil crosslinking agent: 1 part; platinum catalyst: 5 ppm (based on the weight of vinyl-terminated polydimethylsiloxane); hydrophobic fumed silica: 2 parts; The method for preparing the hydrophilic skeleton includes the following steps: S11. Acrylamide, N'N-dimethylbisacrylamide and ammonium persulfate are added to water in a mass ratio of 5:0.05:0.085:50. The mixture is stirred until a homogeneous aqueous phase is obtained. S12. Dissolve Span-40 in cyclohexane at a mass ratio of 1:100 to obtain an oil phase; S13. Add the aqueous phase dropwise to the oil phase, with a ratio of oil phase to aqueous phase of 3:1. Stir while adding the aqueous phase, and stir in a 45°C water bath at a stirring rate of 350 r / min. After the reaction is complete, cool down, filter and dry to obtain micron water-absorbing particles. S14. Dissolve cellulose acetate powder in trifluoroacetic acid and stir at room temperature until a homogeneous solution is formed; S15. Add the micron-sized water-absorbing particles to the solution prepared in S14, stir and mix evenly to obtain a spinning solution, wherein the mass fraction of the micron-sized water-absorbing particles in the spinning solution is 20 wt%. S16. Electrospinning was performed on the spinning solution. The distance from the spinneret to the collecting plate was 10 cm, the voltage was 12 kV, and the spinning speed was 0.25 mL / h, resulting in a hydrophilic framework with a porosity of 90.2%.

[0021] Example 3

[0022] A waterproof shaped tape includes a substrate layer and an adhesive layer. The edge of the substrate layer is not straight but curved. The adhesive layer includes a continuous hydrophobic matrix phase and a hydrophilic skeleton phase. The continuous hydrophobic matrix phase is composed of a hydrophobic mixture A, forming the main continuous phase of the tape and providing adhesion and basic water resistance. The hydrophilic skeleton phase is composed of an electrospun membrane loaded with superabsorbent micron particles, and the hydrophilic skeleton is dispersed in the hydrophobic matrix phase. The above-mentioned method for preparing waterproof shaped tape includes the following steps: S1. Cut the substrate into curved edges; S2. A hydrophilic skeleton is stacked on the surface of the cut substrate layer; S2. Apply hydrophobic mixture A to the side of the substrate layer containing the hydrophilic skeleton, wherein the hydrophobic mixture A is 65 g / m². 2 After being scraped and cured, waterproof shaped tape is obtained; The hydrophobic mixture A comprises the following components by weight: Vinyl-terminated polydimethylsiloxane: 100 parts; MQ silicone resin tackifier: 30 parts; hydrogen-containing silicone oil crosslinking agent: 4 parts; platinum catalyst: 20 ppm (based on the weight of vinyl-terminated polydimethylsiloxane); hydrophobic fumed silica: 3 parts; The method for preparing the hydrophilic skeleton includes the following steps: S11. Acrylamide, N'N-dimethylbisacrylamide and ammonium persulfate are added to water in a mass ratio of 5:0.045:0.075:50. The mixture is stirred until a homogeneous aqueous phase is obtained. S12. Dissolve Span-40 in cyclohexane at a mass ratio of 1.4:100 to obtain an oil phase; S13. Add the aqueous phase dropwise to the oil phase at a ratio of 2:1, stirring while adding. Stir at a water bath temperature of 45°C and a stirring rate of 350 r / min. After the reaction is complete, cool down, filter and dry to obtain micron-sized water-absorbing particles. S14. Dissolve cellulose acetate powder in trifluoroacetic acid and stir at room temperature until a homogeneous solution is formed; S15. Add the micron-sized water-absorbing particles to the solution prepared in S14, stir and mix evenly to obtain a spinning solution, wherein the mass fraction of the micron-sized water-absorbing particles in the spinning solution is 18 wt%. S16. Electrospinning was performed on the spinning solution. The distance from the spinneret to the collecting plate was 12 cm, the voltage was 12 kV, and the spinning speed was 0.3 mL / h, resulting in a hydrophilic framework with a porosity of 87.6%.

[0023] Example 4

[0024] A waterproof shaped tape includes a substrate layer and an adhesive layer. The edge of the substrate layer is not straight but curved. The adhesive layer includes a continuous hydrophobic matrix phase and a hydrophilic skeleton phase. The continuous hydrophobic matrix phase is composed of a hydrophobic mixture A, forming the main continuous phase of the tape and providing adhesion and basic water resistance. The hydrophilic skeleton phase is composed of an electrospun membrane loaded with superabsorbent micron particles, and the hydrophilic skeleton is dispersed in the hydrophobic matrix phase. The above-mentioned method for preparing waterproof shaped tape includes the following steps: S1. Cut the substrate into curved edges; S2. A hydrophilic skeleton is stacked on the surface of the cut substrate layer; S2. Apply hydrophobic mixture A to the side of the substrate layer containing the hydrophilic skeleton, wherein the hydrophobic mixture A is 65 g / m². 2 After being scraped and cured, waterproof shaped tape is obtained; The hydrophobic mixture A comprises the following components by weight: Vinyl-terminated polydimethylsiloxane: 100 parts; MQ silicone resin tackifier: 40 parts; hydrogen-containing silicone oil crosslinking agent: 2 parts; platinum catalyst: 20~40 ppm (based on the weight of vinyl-terminated polydimethylsiloxane); hydrophobic fumed silica: 8 parts; The method for preparing the hydrophilic skeleton includes the following steps: S11. Acrylamide, N'N-dimethylbisacrylamide and ammonium persulfate are added to water in a mass ratio of 5:0.05:0.08:50. The mixture is stirred until a homogeneous aqueous phase is obtained. S12. Dissolve Span-40 in cyclohexane at a mass ratio of 1.2:100 to obtain an oil phase; S13. Add the aqueous phase dropwise to the oil phase, with a ratio of oil phase to water phase of 3:1. Stir while adding the aqueous phase, and stir in a 50°C water bath at a stirring rate of 300 r / min. After the reaction is complete, cool down, filter and dry to obtain micron water-absorbing particles. S14. Dissolve cellulose acetate powder in trifluoroacetic acid and stir at room temperature until a homogeneous solution is formed; S15. Add the micron-sized water-absorbing particles to the solution prepared in S14, stir and mix evenly to obtain a spinning solution, wherein the mass fraction of the micron-sized water-absorbing particles in the spinning solution is 12 wt%. S16. Electrospinning was performed on the spinning solution with a spinneret distance of 10 cm from the collecting plate, a voltage of 12 kV, and a spinning speed of 0.35 mL / h to obtain a hydrophilic framework with a porosity of 90.9%.

[0025] Example 5

[0026] A waterproof shaped tape includes a substrate layer and an adhesive layer. The edge of the substrate layer is not straight but curved. The adhesive layer includes a continuous hydrophobic matrix phase and a hydrophilic skeleton phase. The continuous hydrophobic matrix phase is composed of a hydrophobic mixture A, forming the main continuous phase of the tape and providing adhesion and basic water resistance. The hydrophilic skeleton phase is composed of an electrospun membrane loaded with superabsorbent micron particles, and the hydrophilic skeleton is dispersed in the hydrophobic matrix phase. The above-mentioned method for preparing waterproof shaped tape includes the following steps: S1. Cut the substrate into curved edges; S2. A hydrophilic skeleton is stacked on the surface of the cut substrate layer; S2. Apply hydrophobic mixture A to the side of the substrate layer containing the hydrophilic skeleton, wherein the hydrophobic mixture A is 65 g / m². 2 After being scraped and cured, waterproof shaped tape is obtained; The hydrophobic mixture A comprises the following components by weight: Vinyl-terminated polydimethylsiloxane: 100 parts; MQ silicone tackifier: 35 parts; hydrogen-containing silicone oil crosslinking agent: 3 parts; platinum catalyst: 30 ppm (based on the weight of vinyl-terminated polydimethylsiloxane); hydrophobic fumed silica: 5 parts; The method for preparing the hydrophilic skeleton includes the following steps: S11. Acrylamide, N'N-dimethylbisacrylamide and ammonium persulfate are added to water in a mass ratio of 5:05:0.08:50. The mixture is stirred until a homogeneous aqueous phase is obtained. S12. Dissolve Span-40 in cyclohexane at a mass ratio of 1.3:100 to obtain an oil phase; S13. Add the aqueous phase dropwise to the oil phase at a ratio of 2.5:1, stirring while adding. Stir at a water bath temperature of 50°C at a stirring rate of 320 r / min. After the reaction is complete, cool down, filter and dry to obtain micron-sized water-absorbing particles. S14. Dissolve cellulose acetate powder in trifluoroacetic acid and stir at room temperature until a homogeneous solution is formed; S15. Add the micron-sized water-absorbing particles to the solution prepared in S14, stir and mix evenly to obtain a spinning solution, wherein the mass fraction of the micron-sized water-absorbing particles in the spinning solution is 15 wt%. S16. Electrospinning was performed on the spinning solution. The distance from the spinneret to the collecting plate was 11 cm, the voltage was 14 kV, and the spinning speed was 0.3 mL / h, resulting in a hydrophilic framework with a porosity of 92.6%.

[0027] Comparative Example 1 The difference between Comparative Example 1 and Example 5 is that the edge of the tape is a straight edge.

[0028] Comparative Example 2 The difference between Comparative Example 2 and Example 5 is that the hydrophilic framework does not contain micron-sized water-absorbing particles.

[0029] Comparative Example 3 The difference between Comparative Example 3 and Example 5 is that the porosity of the hydrophilic skeleton in the hydrophilic skeleton is 55.6%.

[0030] Comparative Example 4 The difference between Comparative Example 4 and Example 5 is that the mass fraction of the micron-sized water-absorbing particles in step S15 is 5 wt%.

[0031] Comparative Example 5 The difference between Comparative Example 5 and Example 5 is that the stirring speed in step S13 is 500 r / min.

[0032] Performance testing: The tapes prepared in the examples and comparative examples were cut into tape samples with a specification of 50×200mm. They were then bonded to the simulated substrate according to the actual usage method and rolled back and forth 3 times with a rolling roller (pressure 20±2kPa) to ensure that the tape was tightly bonded to the simulated interface without bubbles, curling edges, or gaps. After bonding, the tapes were placed in a standard environment with a temperature of 23±2℃ and a relative humidity of 50%±5% for 24 hours to ensure that the adhesive layer was completely cured and the bonding state was stable.

[0033] (1) IPX6 strong water jet impact test (simulated water flow scouring): IPX6 dedicated testing equipment was used. The test water temperature was adjusted to 23±2℃, the water flow pressure was controlled at 80±5kPa, the nozzle diameter was 12.5mm, and the distance between the nozzle and the tape bonding interface was maintained at 30±5cm. During the test, the irregularly shaped simulated substrate with tape was fixed, and the nozzle was aimed at the curved edge of the tape and the bonding interface. Spraying was carried out at three angles of 30°, 60°, and 90°, with each angle spraying time being 30s, and the total spraying time being 1.5min. After spraying, the bonding interface and the tape surface were wiped with dry filter paper to check whether the filter paper was wetted and to determine whether there was water penetration.

[0034] (2) IPX7 immersion test (simulated short-term immersion): Prepare a constant temperature water bath with a depth of not less than 1.2m and adjust the water temperature to 23±2℃. Immerse the sample that has completed the IPX6 test and has no penetration into the water bath together with the irregularly shaped simulated substrate. Ensure that the sample is completely submerged at a depth of 1.0±0.1m. The immersion time is strictly controlled to 30min. During the immersion, keep the water temperature in the water bath stable and avoid water flow disturbing the sample. After the immersion, slowly take out the sample and quickly wipe the surface moisture of the sample with a dry soft cloth. After standing for 10min, remove the adhesive tape from the interface with the simulated substrate and check whether there are water stains or delamination in the interface, adhesive tape layer and hydrophilic skeleton phase.

[0035]

[0036] Through comparative analysis of the embodiments and comparative examples, it can be seen that the curved edge structure, the component ratio of the hydrophobic mixture A, and the hydrophilic skeleton phase loaded with superabsorbent micron particles of the present invention all play a key role in the waterproof performance and structural stability of the tape. The synergistic effect of each part forms a dual waterproof mechanism of passive barrier and active sealing.

[0037] Comparative Example 1 only changed the edge of the tape to a straight edge. Its IPX6 strong water jet impact test showed slight water penetration. The curved edge can change the direction of water flow, reduce the scouring force of water flow on the edge of the tape and the bonding interface, and reduce the retention and penetration of water flow at the interface. The straight edge cannot achieve this effect. Strong water flow can easily form a scouring dead angle along the straight edge, resulting in slight water penetration. The hydrophilic skeleton of Comparative Example 2 does not contain micron-sized water-absorbing particles. In the dry state, the hydrophilic skeleton mainly relies on the fiber structure for support. Although it can achieve basic water resistance when it does not contain micron-sized water-absorbing particles and works with the hydrophobic matrix phase, it cannot swell when exposed to water, cannot compress and densify the hydrophobic matrix phase, and cannot fill the micro-gaps at the interface. This results in water molecules slowly penetrating during long-term immersion. At the same time, due to the lack of interfacial adhesion generated by swelling, slight delamination occurs at the edges. The porosity of the hydrophilic skeleton of Comparative Example 3 is only 55.6%, indicating that the porosity of the hydrophilic skeleton is a key parameter affecting its swelling performance and structural stability. When the porosity is too low, the fiber structure of the hydrophilic skeleton is too dense. On the one hand, it will limit the swelling space of the superabsorbent micron particles, resulting in insufficient swelling and inability to achieve effective extrusion densification and gap filling. On the other hand, it will reduce the flexibility of the hydrophilic skeleton, resulting in a decrease in its adhesion to the hydrophobic matrix phase and substrate. After immersion in water, it is easy for interface peeling to occur, which in turn leads to water penetration. The mass fraction of micron water-absorbing particles in Comparative Example 4 is only 5wt%, indicating that the loading of micron water-absorbing particles is insufficient and cannot achieve effective active sealing. When the mass fraction of micron-sized water-absorbing particles is too low, the swelling volume generated after contact with water is limited, which is insufficient to generate enough compression and densification effect on the hydrophobic matrix phase, and also cannot fully fill the micro gaps at the interface, resulting in slight penetration when subjected to strong water flow and long-term immersion. At the same time, insufficient loading will reduce the bonding force between the hydrophilic skeleton and the hydrophobic matrix phase, and edge peeling is likely to occur after immersion. This proves that the mass fraction range of 10-20 wt% of micron-sized water-absorbing particles in this invention can ensure that their swelling performance is fully utilized and achieve the synergistic effect of the dual waterproof mechanism. The stirring rate of the reverse emulsion polymerization in Comparative Example 5 is 500 r / min, indicating that the stirring rate of the reverse emulsion polymerization affects the particle size and dispersibility of the micron-sized water-absorbing particles. Excessive stirring speed can lead to excessively small particle size and uneven dispersion of the prepared micron-sized water-absorbing particles. On the one hand, this reduces their water absorption and swelling performance, making it impossible to achieve effective active sealing. On the other hand, particles with uneven particle size can disrupt the continuity of the fiber structure of the hydrophilic skeleton, resulting in a decrease in the bonding force between the hydrophilic skeleton and the hydrophobic matrix phase. This makes them prone to edge peeling after immersion in water. This demonstrates that the stirring speed range of 300-350 r / min in this invention can prepare micron-sized water-absorbing particles with uniform particle size and stable water absorption performance, ensuring the functional reliability of the hydrophilic skeleton.

[0038] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A waterproof irregularly shaped tape, characterized in that: The irregularly shaped tape includes a substrate layer and an adhesive layer. The edge of the substrate layer is not straight but curved. The adhesive layer includes a continuous hydrophobic matrix phase and a hydrophilic skeleton phase. The continuous hydrophobic matrix phase is composed of a hydrophobic mixture A, forming the main continuous phase of the tape and providing adhesion and basic water resistance. The hydrophilic skeleton phase is composed of an electrospun film loaded with superabsorbent micron particles, and the hydrophilic skeleton is dispersed in the hydrophobic matrix phase. The hydrophilic framework phase has the property of swelling when exposed to water. It maintains its framework shape in a dry state and undergoes anisotropic or isotropic volume expansion when exposed to water, which compresses and densifies the surrounding hydrophobic matrix phase. At the same time, the framework itself swells and fills the interfacial gaps, forming a water molecule diffusion blocking mechanism.

2. The waterproof irregular-shaped tape according to claim 1, characterized in that: The hydrophobic mixture A comprises the following components by weight: Vinyl-terminated polydimethylsiloxane: 100 parts MQ silicone tackifier: 20-50 parts Hydrogen-containing silicone oil crosslinking agent: 1-5 parts Platinum catalyst: 5~50 ppm Hydrophobic fumed silica: 0~10 parts.

3. The waterproof irregular-shaped tape according to claim 1, characterized in that: The method for preparing the hydrophilic skeleton includes the following steps: S11. Acrylamide, N'N-dimethylbisacrylamide and ammonium persulfate are added to water and mixed evenly to obtain an aqueous phase; S12. Dissolve Span-40 in cyclohexane to obtain an oil phase; S13. Add the aqueous phase dropwise to the oil phase while stirring. Stir at a water bath temperature of 45-50°C at a stirring rate of 300-350 r / min. After the reaction is complete, cool down, filter and dry to obtain micron-sized water-absorbing particles. S14. Dissolve cellulose acetate powder in trifluoroacetic acid and stir at room temperature until a homogeneous solution is formed; S15. Add the micron-sized water-absorbing particles to the solution prepared in S14, stir and mix evenly to obtain the spinning solution; S16. Electrospin the spinning solution, with the distance from the spinneret to the collecting plate being 10~12cm, the voltage being 12~15 kV, and the spinning speed being 0.25~0.4mL / h, to obtain a hydrophilic skeleton.

4. The waterproof irregular-shaped tape according to claim 3, characterized in that: The mass ratio of acrylamide, N'N-dimethylbisacrylamide, ammonium persulfate and water in S11 is 5:0.04~0.05:0.07~0.085:

50.

5. The waterproof irregular-shaped tape according to claim 3, characterized in that: The mass ratio of Span-40 to cyclohexane in S12 is 1~1.5:

100.

6. The waterproof irregular-shaped tape according to claim 3, characterized in that: The ratio of oil phase to water phase in S13 is 2~3:

1.

7. The waterproof irregular-shaped tape according to claim 3, characterized in that: The mass fraction of micron-sized water-absorbing particles in the spinning solution of S15 is 10~20wt%.

8. The waterproof irregular-shaped tape according to claim 3, characterized in that: The porosity of the hydrophilic skeleton is greater than 80%.

9. The method for preparing waterproof irregularly shaped adhesive tape according to claim 1, characterized in that, Includes the following steps: S1. Cut the substrate into curved edges; S2. A hydrophilic skeleton is stacked on the surface of the cut substrate layer; S2. Coat the hydrophobic mixture onto the side of the substrate layer containing the hydrophilic skeleton, and cure it after scraping to obtain a waterproof shaped tape.

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