Self-adaptive adhesive tape with humidity response viscosity

Abstract

The invention discloses a self-adaptive adhesive tape with humidity response viscosity, and the self-adaptive adhesive tape comprises a humidity-sensitive matrix layer which is made of a high polymer material with humidity response characteristic, and the high polymer material comprises the following components in percentage by mass: 50-70% of polyvinyl alcohol; carboxymethyl cellulose with a mass percentage of 10%-20%; the dynamic cross-linking layer is uniformly distributed in the humidity-sensitive matrix layer or on the surface of the humidity-sensitive matrix layer, is formed by phenylboronic acid and a polyhydroxy compound through a dynamic reversible cross-linking reaction, and is used for regulating and controlling the viscosity of the material when the humidity is changed; the base material layer is used for supporting the humidity-sensitive base body layer, the base material layer is a flexible polyester film or a paper base material with the thickness of 20-100 microns, the humidity-sensitive base body layer not only has excellent dynamic humidity response capability and mechanical properties, but also has high environmental adaptability and long-term economy, and the application prospects of the humidity-sensitive base body layer in the fields of medical treatment, packaging, electronics, buildings and the like are remarkably expanded.

Description

Technical Field

[0001] The invention belongs to the technical field of adhesive tapes, and in particular relates to an adaptive adhesive tape with humidity-responsive viscosity. Background Art

[0002] As a common adhesive tool, tape is widely used in packaging, assembly, medical treatment, electronic equipment fixation and other fields. However, the function of traditional tape is usually relatively simple, and its viscosity cannot be adaptively adjusted according to environmental conditions (such as humidity changes). In practical applications, it has the following limitations:

[0003] Humidity has a significant impact on viscosity: In high humidity environments, traditional tapes lose viscosity due to water penetration, and are prone to falling off or failure, especially in high humidity scenarios such as cold chain transportation and bathroom decoration. In low humidity or dry environments, traditional tapes may damage the surface of the attachment due to excessive viscosity, such as excessive pulling on the skin in medical patch applications.

[0004] Difficult to adapt to dynamic humidity changes: The viscosity of traditional tapes is usually fixed, which makes it difficult to meet the use requirements in dynamic humidity environments, such as attaching flexible electronic devices or sealing smart packaging.

[0005] Insufficient breathability and comfort: Especially in medical applications, traditional tapes have poor breathability, which may cause stuffiness or moisture accumulation on the skin, causing skin discomfort or secondary damage.

[0006] In view of the limitations of traditional tapes and existing moisture-sensitive tapes, the market demand urgently requires an adaptive tape with the following characteristics:

[0007] Dynamic humidity response capability: It can automatically adjust the viscosity according to the changes in ambient humidity to adapt to the different needs of high humidity and low humidity environments.

[0008] Quick response and breathability: It can quickly adjust the adhesion performance when the humidity changes, while ensuring smooth moisture transfer, providing a comfortable use experience.

[0009] High mechanical strength and long-term stability: It has good tensile strength and moisture resistance, and can work stably for a long time in high humidity or humidity cycle environment.

[0010] Low cost and easy production: The preparation method is simple, the material cost is low, and it is suitable for large-scale production. Summary of the invention

[0011] The purpose of the present invention is to provide an adaptive adhesive tape with humidity-responsive viscosity, which not only has excellent dynamic humidity response capability and mechanical properties, but also has high environmental adaptability and long-term economy, significantly expanding its application prospects in the fields of medical treatment, packaging, electronics and construction.

[0012] The technical solution adopted by the present invention is as follows:

[0013] An adaptive adhesive tape with humidity-responsive adhesiveness, comprising:

[0014] The humidity-sensitive substrate layer is made of a polymer material having humidity-responsive properties, and the polymer material includes:

[0015] Polyvinyl alcohol, mass percentage is 50%-70%;

[0016] Carboxymethyl cellulose, mass percentage is 10%-20%;

[0017] The dynamic cross-linking layer is evenly distributed in the humidity-sensitive substrate layer or on its surface, and is formed by a dynamic reversible cross-linking reaction between phenylboronic acid and a polyhydroxy compound, and is used to control the viscosity of the material when the humidity changes;

[0018] The substrate layer is used to support the moisture-sensitive base layer, and the substrate layer is a flexible polyester film or paper substrate with a thickness of 20-100 microns.

[0019] Wherein, the humidity-sensitive matrix layer further comprises:

[0020] Talc or bentonite, with a mass percentage of 5%-10%, is used to enhance the mechanical strength and hygroscopicity of the moisture-sensitive substrate layer.

[0021] Wherein, the dynamic cross-linking layer further comprises:

[0022] Glutaraldehyde, with a mass percentage of 1%-5%, is used for preliminary cross-linking and enhancing the viscosity regulating ability of the moisture-sensitive substrate layer.

[0023] The dynamic cross-linking layer forms a high-viscosity state through rearrangement of borate cross-linking bonds when the humidity increases, and restores to a low-viscosity state through breaking of cross-linking bonds when the humidity decreases.

[0024] The surface of the humidity-sensitive substrate layer has a micro-nano pore structure, and the pore structure is prepared by solution-phase separation technology to improve the humidity response speed.

[0025] Wherein, the humidity-sensitive matrix layer further comprises:

[0026] The polar modifier is a fatty acid salt or a glyceride, with a mass percentage of 0.5%-2%, and is used to improve the surface energy and viscosity adjustment performance of the moisture sensitive layer.

[0027] The moisture-sensitive matrix layer and the dynamic cross-linking layer are prepared by a solution blending method and are cured and formed at 40-60°C.

[0028] The dynamic cross-linking layer is formed by the reaction of 2%-5% by mass of phenylboric acid with the polyhydroxy compound in the moisture-sensitive matrix.

[0029] A method for preparing the adaptive adhesive tape with humidity-responsive adhesiveness comprises the following steps:

[0030] 1) Solution mixing:

[0031] Dissolve polyvinyl alcohol in 80-90°C water and stir until completely dissolved to form a transparent solution;

[0032] After cooling to 40-50°C, add carboxymethyl cellulose and continue stirring to form a uniform moisture-sensitive matrix solution;

[0033] Add the reinforcing ingredient talc or bentonite to the solution and stir at high speed until it is completely dispersed;

[0034] Phenylboronic acid and glutaraldehyde were added and stirred at room temperature to partially initiate a preliminary cross-linking reaction;

[0035] Finally, a polar modifier is added to further enhance the moisture-sensitive viscosity adjustment performance of the solution;

[0036] 2) Substrate treatment and coating:

[0037] Choose a flexible polyester film or paper substrate with a thickness of 20-100 microns, and use plasma cleaning or surface chemical treatment to enhance the adhesion of the substrate;

[0038] The mixed wet-sensitive solution is evenly coated on the surface of the substrate by a casting method or a spraying method, and the coating thickness of the wet-sensitive layer is controlled to be 50-100 microns;

[0039] 3) Surface treatment:

[0040] spraying phenylboric acid solution on the coated moisture-sensitive substrate layer to further form a dynamic cross-linking layer;

[0041] A volatile porogen is introduced on the surface of the moisture sensitive layer, and a micro-nano pore structure is formed in the subsequent drying process through solution-phase separation technology to improve the response speed of the moisture sensitive layer;

[0042] 4) Curing and molding:

[0043] Use hot air drying equipment to perform low-temperature curing at 40-60°C to gradually evaporate the moisture in the moisture-sensitive matrix layer and complete the formation of a dynamic cross-linking network;

[0044] During the curing process, glutaraldehyde undergoes further covalent crosslinking with polyvinyl alcohol or carboxymethyl cellulose to ensure the mechanical stability of the moisture-sensitive layer;

[0045] After curing, the tape is left to stand at room temperature to optimize the structural uniformity and performance stability of the dynamically cross-linked layer;

[0046] 5) Finished product cutting:

[0047] The cured moisture-sensitive tape is cut according to actual application requirements, and finally an adaptive tape with humidity-responsive viscosity is obtained.

[0048] In the present invention, the multi-layer structure of the tape (humidity-sensitive base layer, dynamic crosslinking layer, substrate layer) and the optimized preparation method give it unique humidity response characteristics and mechanical properties, and its main beneficial effects are:

[0049] 1. Dynamic humidity response characteristics

[0050] Through the reversible cross-linking reaction of the dynamic cross-linking layer, the adhesive tape loses its stickiness when the humidity increases and recovers its stickiness when the humidity decreases. When the humidity increases, phenylboronic acid and the polyhydroxyl groups in polyvinyl alcohol (PVA) or carboxymethyl cellulose (CMC) rearrange their cross-linking bonds, reducing the cross-linking density and reducing the stickiness. When the humidity decreases, the cross-linking bonds recover to form a tight dynamic network, and the stickiness increases. Due to their excellent hygroscopicity, PVA and CMC expand or contract when the humidity changes, adjusting the surface energy and contact area of ​​the tape. It can flexibly adapt to humidity changes and can be used in scenarios where dynamic adjustment of adhesion is required.

[0051] 2. Fast humidity response

[0052] The tape can respond to humidity changes within 2-3 seconds, achieving rapid viscosity adjustment. The hierarchical pores (macropores and micropores) formed by solution-phase separation technology increase the moisture transfer rate: adding polar modifiers (fatty acid salts or glycerides) increases the surface energy of the moisture-sensitive layer, further improving moisture transfer and response speed.

[0053] 3. High mechanical strength and structural stability

[0054] The tensile strength of the tape reaches 10MPa, and the humidity cycle life exceeds 350 times, with excellent mechanical properties and long-term stability. Glutaraldehyde reacts with the hydroxyl groups in PVA and CMC to form stable covalent bonds, which improves the mechanical strength of the moisture-sensitive layer. The flaky structure of talcum powder enhances the tensile properties of the moisture-sensitive layer; the hygroscopic properties of bentonite provide mechanical support for the moisture-sensitive matrix to avoid performance degradation caused by moisture. It is suitable for high-load and long-term attachment needs, and can still maintain stable performance in multiple humidity changes.

[0055] 4. Strong environmental adaptability

[0056] The tape can maintain stable performance in the range of 30%-80% humidity, meeting the needs of various environments. The rupture and reconstruction of the borate bond are highly reversible, ensuring the balance of crosslinking density in humidity changes. The synergistic effect of PVA and CMC gives the base layer a wide humidity adaptability range. It can work stably from high humidity to low humidity.

[0057] 5. Long-term economic and environmental performance

[0058] The tape has a long service life, a humidity cycle performance of more than 350 times, and is made of environmentally friendly materials. PVA and CMC are water-soluble and degradable materials; talcum powder and bentonite are non-toxic natural enhancers. Through simple solution blending and low-temperature curing process, the production cost is reduced, which is suitable for green agriculture and smart packaging and other fields with high environmental requirements, reducing replacement frequency and maintenance costs.

[0059] 6. Strong application adaptability

[0060] The tape is compatible with a variety of substrates (flexible polyester film or paper substrate) to meet different application requirements. Plasma cleaning or surface chemical treatment improves the adhesion performance of the substrate surface; uniform coating thickness (50-100μm) enhances the bonding strength between the moisture-sensitive layer and the substrate. From flexible electronics to architectural decoration, it can provide reliable adhesion performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 It is a schematic diagram of the process of the present invention. DETAILED DESCRIPTION

[0062] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0063] See also Figure 1 , the present invention relates to an adaptive adhesive tape with humidity-responsive viscosity, the material composition and mass percentage of which are as follows:

[0064] Humidity sensitive substrate layer:

[0065] Polyvinyl alcohol (PVA): 50%-70%, providing moisture-sensitive properties and mechanical strength.

[0066] Carboxymethyl cellulose (CMC): 10%-20%, enhances flexibility and moisture absorption capacity.

[0067] Talc or bentonite: 5%-10%, improve the mechanical properties and hygroscopicity of the matrix.

[0068] Dynamic cross-linking layer:

[0069] Phenylboronic acid: 2%-5%, reacts with polyhydroxy compounds to form reversible dynamic crosslinks.

[0070] Glutaraldehyde: 1%-5%, enhances the initial cross-linking strength of the matrix.

[0071] Graded Porosity Porogen:

[0072] Diethanolamine (DEA): 1%-3%, forms macropores (>1μm).

[0073] Urea: 2%-5%, forms micropores (<100nm).

[0074] Polar modifiers:

[0075] Glycerides or fatty acid salts: 0.5%-2%, to increase the surface energy and viscosity regulating ability of the moisture-sensitive layer.

[0076] Substrate layer:

[0077] Flexible polyester film or paper substrate, thickness 20-100 microns.

[0078] The preparation method of the adaptive tape is as follows:

[0079] Step 1: Solution Mixing

[0080] 1) Dissolving polymer materials:

[0081] Dissolve polyvinyl alcohol (PVA) in water at 80-90°C and stir until it becomes completely transparent to form a uniform solution. After the molecular chain of PVA is unfolded, its large number of hydroxyl groups (–OH) interact with water molecules through hydrogen bonds to form a uniform polymer network.

[0082] After cooling to 40-50°C, carboxymethyl cellulose (CMC) is added and stirred continuously to prepare a moisture-sensitive matrix solution. After cooling to 40-50°C, CMC is added, and the carboxyl groups (–COOH) and hydroxyl groups (–OH) of carboxymethyl cellulose diffuse in the solution and form secondary bonds with PVA molecules, increasing the viscosity and flexibility of the solution.

[0083] PVA and CMC are both water-soluble polymer materials with good compatibility. The hydroxyl groups of PVA and the carboxyl groups of CMC form crosslinking points through hydrogen bonds, which improve the uniformity and mechanical properties of the humidity-sensitive substrate layer.

[0084] 2) Add strengthening ingredients:

[0085] Add talcum powder (or bentonite) to the humidity-sensitive matrix solution and stir at high speed until it is completely dispersed. The layered structure of talcum powder enables it to be distributed in the solution and form a physical bond with the PVA-CMC matrix material. The addition of talcum powder particles improves the mechanical strength of the humidity-sensitive matrix layer. At the same time, due to its inertness and hydrophobicity, it limits excessive absorption of water and optimizes the humidity response range. Bentonite has a large specific surface area and hygroscopicity, can form colloids in water, and has a large number of hydroxyl groups (–OH) on the surface of the particles, which can further enhance the hygroscopic properties of the humidity-sensitive layer.

[0086] Adding phenylboronic acid and glutaraldehyde partially initiates the initial cross-linking reaction. Phenylboronic acid forms borate bonds with polyhydroxyl groups (–OH) in PVA and CMC to build a dynamic cross-linking network. When the humidity changes, the borate bonds can be reversibly broken or rearranged, giving the material the ability to adjust humidity-sensitive viscosity. Reaction equation: Glutaraldehyde reacts with the hydroxyl (–OH) or carboxyl (–COOH) in PVA and CMC through the aldehyde group (–CHO) to form a stable covalent bond. The initial cross-linking increases the strength of the matrix solution and prevents excessive shrinkage or deformation during coating and drying. Reaction equation: PVA-OH+CHO-CH2-CHO→PVA-O-CH2-O-PVA.

[0087] 3) Porogen Mixing:

[0088] Add diethanolamine (DEA) and urea, and continue stirring to ensure that the dual-aperture porogen is evenly dispersed. Diethanolamine (DEA) forms larger molecular aggregates in the solution. It evaporates quickly during the drying process, leaving macroscopic pores (>1μm) to form a fast moisture transfer channel for the moisture-sensitive layer. Urea is evenly distributed in the solution and partially precipitates during the drying process, leaving micropores (<100nm), increasing the specific surface area of ​​the moisture-sensitive layer and enhancing dynamic performance.

[0089] 4) Add polar modifier:

[0090] Adding glycerides or fatty acid salts to the solution can further improve the viscosity adjustment performance. Glycerides or fatty acid salts can form a polar molecular layer on the surface of the moisture-sensitive substrate and increase the surface energy of the moisture-sensitive layer. Under wet conditions, the modifier enhances the intermolecular force between the moisture-sensitive layer and the external interface, thereby significantly improving the viscosity adjustment performance.

[0091] Step 2: Substrate preparation and coating

[0092] 1) Substrate treatment:

[0093] Choose a flexible polyester film or paper substrate with a thickness of 20-100 microns; polyester film (such as PET) has excellent tensile strength and weather resistance, ensuring the stability of moisture-sensitive tape in complex environments. The surface of polyester film is smooth and highly inert, making it easy to introduce a surface functional layer in subsequent processing. Paper substrates have high water absorption and porous structure, and can achieve strong mechanical bonding with the moisture-sensitive base layer. Degradable paper substrates are suitable for the application scenarios of environmentally friendly moisture-sensitive tapes.

[0094] Plasma cleaning or chemical treatment is performed on the surface of the substrate to enhance its adhesion performance. Plasma cleaning generates active functional groups (such as hydroxyl or carboxyl) on the surface of the substrate. The high-energy particles in the plasma bombard the surface of the substrate, breaking its chemical inertness. The generated hydroxyl and carboxyl groups are combined with the polymer materials (PVA and CMC) of the moisture-sensitive matrix layer through hydrogen bonds or chemical bonds, thereby enhancing the mechanical bonding force between the moisture-sensitive matrix layer and the substrate; improving the uniformity of the coating solution on the surface of the substrate. Chemical treatment uses chemical reagents (such as sodium salt solutions) to roughen the surface of the substrate, increase the specific surface area, and provide more mechanical locking points to improve the adhesion performance of the moisture-sensitive solution when applied.

[0095] 2) Moisture-sensitive substrate coating:

[0096] The moisture-sensitive solution is evenly coated on the surface of the substrate by the casting method, and the coating thickness is controlled at 50-100 microns. The casting process uses a scraper or template to control the thickness of the solution to ensure the uniformity of the coating layer; the solution is spread on the surface of the substrate and evenly distributed through surface tension, which is suitable for smooth and highly stretchable substrates (such as flexible polyester films); the spraying process uses a high-speed nozzle to atomize the solution so that it covers the surface of the substrate in the form of fine droplets; the droplets spread rapidly on the surface of the substrate to form a coating, which is more suitable for porous or rough substrates (such as paper substrates).

[0097] Step 3: Surface Preparation

[0098] 1) Dynamic cross-linking layer spraying:

[0099] Spray phenylboric acid solution on the surface of the humidity-sensitive substrate layer to form a dynamic cross-linking layer. Phenylboric acid (B(OH)3) reacts with polyhydroxy compounds (such as –OH in PVA and CMC) in the humidity-sensitive substrate to form borate ester bonds. The borate ester bonds have humidity response characteristics: when the humidity increases, the borate ester bonds are partially broken or rearranged by the action of water molecules to form a high viscosity state; when the humidity decreases, the borate ester bonds are stabilized again and return to a low viscosity state. Reaction equation: The spraying process makes the phenylboric acid solution evenly distributed on the surface of the humidity-sensitive substrate to form a dynamic cross-linking layer. The thickness of the dynamic cross-linking layer directly affects the viscosity adjustment range and humidity response speed of the humidity-sensitive tape.

[0100] 2) Construction of hierarchical pore structure:

[0101] In the spraying process, a dual-aperture porogen is introduced to construct a hierarchical pore structure through solution-phase separation technology: after the dual-aperture porogen is distributed in the moisture-sensitive matrix, solution-phase separation occurs with the evaporation of the solvent and the precipitation of water: diethanolamine evaporates rapidly during the drying process, leaving large pores (macropores, >1μm), forming a rapid moisture transmission channel. Urea gradually precipitates or decomposes, leaving micropores (<100nm), providing a larger specific surface area.

[0102] The macropores provide a fast channel for moisture, accelerating humidity transfer; in an environment with rapid humidity changes, it ensures that the moisture-sensitive layer responds promptly.

[0103] The micropores provide a high specific surface area, enhance the moisture adsorption capacity of the moisture-sensitive matrix, and enhance the dynamic viscosity regulation performance of the moisture-sensitive layer.

[0104] The synergistic effect of the dual-aperture porogens allows the presence of both macropores and micropores in the humidity sensitive layer, forming a hierarchical pore structure. The hierarchical structure significantly optimizes the humidity response speed and performance of the humidity sensitive layer.

[0105] Step 4: Curing

[0106] 1) Low temperature curing:

[0107] At 40-60°C, hot air drying equipment is used to gradually evaporate water, while completing the formation of a dynamic cross-linked network, and completing partial cross-linking reactions and volatilization of porogens. The gradual evaporation of water helps to closely arrange the molecular chains in the moisture-sensitive matrix layer, forming a strong physical network. Controlling the low-temperature drying speed can prevent the rapid solidification of the surface from making it difficult to discharge internal moisture and avoid deformation of the internal structure. After the moisture is reduced, the borate bonds between phenylboric acid and polyhydroxy compounds begin to form a stable dynamic cross-linked network, and the reaction of glutaraldehyde further solidifies the structure of the moisture-sensitive layer. Diethanolamine evaporates rapidly during the drying process, leaving macropores; urea precipitates or slowly decomposes to form micropores. Low-temperature drying avoids the destruction of dynamic cross-linked bonds (such as borate bonds) by high temperature, while ensuring that the hierarchical pore structure can be evenly formed.

[0108] Glutaraldehyde further cross-links with PVA and CMC to enhance the mechanical stability of the humidity-sensitive matrix layer. The aldehyde group (–CHO) of glutaraldehyde undergoes a condensation reaction with the hydroxyl group (–OH) in PVA and CMC to form a stable ether bond. This covalent cross-linking enhances the mechanical strength of the humidity-sensitive matrix layer and prevents structural deformation during humidity changes. Reaction equation: PVA-OH+CHO-CH2-CHO→PVA-O-CH2-O-PVA; in this process, as the drying process proceeds, the borate ester bonds gradually reach a chemical equilibrium state to form a stable dynamic cross-linking network. The performance of the dynamic cross-linking layer ensures that the humidity-sensitive layer can respond quickly to humidity changes and adjust the viscosity. The covalent cross-linking of glutaraldehyde provides basic stability for the humidity-sensitive matrix layer; the dynamic cross-linking of phenylboronic acid gives the humidity-sensitive layer humidity responsiveness, and the two synergistically enhance the performance of the humidity-sensitive tape.

[0109] Drying temperature: below 40℃, water evaporates slowly and pore structure is not easy to form; above 60℃, water evaporates too quickly, which may lead to uneven pore distribution.

[0110] Drying time: If the time is too short, the pore structure will not be completely fixed; if the time is too long, it may cause excessive curing of the dynamic cross-linking bonds and affect the moisture-sensitive properties.

[0111] 2) Static treatment:

[0112] The cured moisture-sensitive tape was left at room temperature for 24 hours to optimize the uniformity and performance stability of the dynamic cross-linked layer and pore structure. Balance of the dynamic cross-linked network:

[0113] During the static process, the borate bonds gradually reach chemical equilibrium, and the uniformity and stability of the dynamic cross-linking network are further optimized. The macropores and micropores are finally finalized during the static process, and the hierarchical pore structure is more evenly distributed. The static time helps release the internal stress of the humidity-sensitive matrix layer, avoiding deformation or inconsistent performance in subsequent use.

[0114] After the drying and resting phases, the mechanical properties and dynamic humidity response of the humidity-sensitive layer are optimized. The covalent crosslinking of glutaraldehyde forms a stable molecular skeleton structure, which significantly improves the tensile strength and durability of the humidity-sensitive matrix layer. The dynamic crosslinking of phenylboronic acid ensures that the humidity-sensitive tape can respond quickly and adjust its viscosity when the humidity changes. The hierarchical pore structure provides fast moisture channels (macropores) and high specific surface area (micropores), which significantly improves the humidity response speed of the humidity-sensitive layer.

[0115] Step 5: Cutting the finished product

[0116] According to specific application requirements, the prepared moisture-sensitive tape is cut into required sizes to obtain a final product.

[0117] This adaptive tape has significant performance effects:

[0118] Humidity responsiveness: Moisture-sensitive tape can quickly adjust its viscosity when humidity changes (response speed < 5 seconds), and the viscosity range is significantly improved (10-25N / cm 2 ).

[0119] Hierarchical pore optimization: macropores (>1μm) provide fast moisture transfer channels, micropores (<100nm) increase the specific surface area, and significantly optimize dynamic moisture-sensitive performance.

[0120] Mechanical properties and stability: After adding talc, bentonite and glutaraldehyde, the mechanical strength and structural stability of the humidity-sensitive substrate layer are greatly improved, and the service life exceeds 300 humidity cycles.

[0121] Environmental adaptability: The introduction of polar modifiers makes the surface viscosity adjustment ability of moisture-sensitive tapes more stable in high humidity environments, making them suitable for a variety of complex application scenarios.

[0122] The tapes were prepared within the parameters of the formulation and preparation method, which are summarized below:

[0123]

[0124] Test environment and conditions

[0125] Environmental parameters: Room temperature: 25°C; Humidity range: 30%-80% (dynamic humidity test range)

[0126] Test equipment: Humidity control box: precisely adjust the humidity range and measure the response speed of humidity changes. Dynamic viscosity tester: test the dynamic viscosity adjustment range of humidity-sensitive tape. Tensile tester: measure the tensile strength of the sample. Humidity cycle tester: the humidity cycle range is 30%-80%, and the test is continued until the viscosity performance decreases by 50%.

[0127] Specific test content

[0128] Dynamic viscosity adjustment range (N / cm 2 ): Test the range of adhesive force after the humidity rises from 30% to 80%. Use a dynamic adhesive tester to measure the maximum and minimum values ​​of sample adhesion during humidity changes. Data is recorded as the difference between the maximum and minimum adhesion of a 10cm×10cm sample.

[0129] Humidity response speed (seconds): The time required for the test tape to complete the viscosity adjustment when the humidity is from 30% to 80%. The humidity control box is set to increase the humidity from 30% to 80%, and the time required for the tape to complete the dynamic viscosity adjustment is recorded at the same time.

[0130] Mechanical strength (MPa): Test the tensile strength of the moisture-sensitive tape. Use a tensile testing machine to perform a tensile test in accordance with ISO 527-2 standard and record the maximum tensile strength.

[0131] Humidity cycle life (times): The number of times the test sample cycles from 30% to 80% humidity until performance failure. The failure standard is that the dynamic viscosity adjustment range drops to 50% of the initial performance.

[0132] Test results analysis

[0133] 1. Dynamic viscosity adjustment range

[0134] Solution 3 (20N / cm 2 ) performed best, followed by solution 5 (18N / cm 2 ).

[0135] The adjustment range increases with the increase of phenylboric acid content, and the phenylboric acid content (4%) in scheme 3 is the best, forming a strong dynamic cross-linking network. The reasonable ratio of talc and CMC also enhances the viscosity adjustment ability.

[0136] 2. Humidity response speed

[0137] Solution 3 (2 seconds) has the fastest response speed, followed by Solution 5 (2.5 seconds).

[0138] The hierarchical pore structure (synergistic effect of macropores and micropores) significantly improves the moisture transmission rate, allowing the moisture-sensitive layer to quickly adjust its viscosity. The response speed of scheme 1 is slow (4 seconds), which may be due to the low proportion of porogen, which limits moisture transmission.

[0139] 3. Mechanical strength

[0140] Scheme 3 (10 MPa) has the best mechanical strength, followed by scheme 5 (9.5 MPa).

[0141] The reinforcing effect of talc and the covalent cross-linking effect of glutaraldehyde are the main reasons. The strength is proportional to the content of talc and glutaraldehyde. Talc below 5% (such as Scheme 1) leads to reduced strength.

[0142] 4. Humidity cycle life

[0143] Scheme 3 (350 times) has the longest lifespan, followed by scheme 5 (340 times).

[0144] The borate bonds of the dynamic crosslinking layer and the covalent crosslinking of glutaraldehyde work synergistically to ensure that the humidity-sensitive substrate layer has high stability during humidity cycling. The shorter lifespan schemes (such as scheme 1, 300 times) may result in material degradation during humidity cycling due to insufficient crosslinking point density.

[0145] The adaptive tape is particularly suitable for tapes that need to be adhered to human skin, such as medical patches or band-aids. The process is as follows:

[0146] 1. Increased humidity: The longer the adhesion time, the higher the skin humidity

[0147] When the tape is stuck to the skin for a long time, the humidity between the tape and the skin gradually increases due to sweat secretion or increased environmental humidity. Moisture accumulates on the skin surface, causing the humidity of the local microenvironment to rise to 70%-80%.

[0148] The borate bonds in the dynamic cross-linking layer of the tape are partially broken when the humidity rises, and the cross-linking density is reduced, making the tape less sticky. This change avoids excessive pulling of the tape on the skin and reduces irritation or discomfort.

[0149] The microporous structure of the moisture-sensitive matrix layer expands due to moisture absorption and is transformed into more macropores, which increases the moisture transfer rate, enhances the gas exchange between the skin and the outside world, and reduces the discomfort caused by moisture accumulation (such as stuffiness or skin irritation).

[0150] 2. Decreased humidity: Dry skin or decreased ambient humidity

[0151] As the humidity of the external environment decreases or the moisture on the skin surface is discharged, the local humidity of the skin gradually drops to 30%-50%. At this time, the tape needs to increase its viscosity again to ensure firmness.

[0152] As the humidity of the tape decreases, the borate bonds in the dynamic cross-linking layer are reformed, the cross-linking density increases, and the adhesiveness of the tape is restored or enhanced, providing a strong adhesion and preventing the tape from loosening or falling off.

[0153] The microporous structure returns to its original state, moisture vapor transmission slows down, and the tape becomes denser overall, thereby enhancing adhesion stability.

[0154] 3. Ensure the reliability of tape adhesion under different humidity

[0155] The borate bonds in the dynamic cross-linking layer partially break when the humidity rises, but the cross-linking points are not completely lost. The unbroken borate bonds and the rebalanced cross-linking network ensure the basic adhesion of the moisture-sensitive tape. In addition to the borate bonds, glutaraldehyde provides mechanical support through covalent bonds formed with the hydroxyl groups in PVA and CMC. The cross-linking points of glutaraldehyde are not affected by humidity changes, which enhances the moisture resistance of the dynamic cross-linking layer in high humidity environments.

[0156] In a high humidity environment, even if some borate bonds break, the remaining cross-linking points in the dynamic cross-linking layer still provide a stable network structure. When the moisture reaches a certain concentration, the reaction of the dynamic cross-linking layer tends to equilibrium, the cross-linking density is stable, and the viscosity will not decrease further.

[0157] In addition, after the moisture-sensitive matrix layer (PVA and CMC) absorbs water, the surface of the material expands but does not completely dissociate, maintaining its overall structural stability. Fillers such as talcum powder and bentonite form physical support in the moisture-sensitive matrix layer, resisting deformation caused by moisture and enhancing viscosity.

[0158] The hierarchical pore structure (macropores and micropores) opens more moisture transfer channels in a high humidity environment, allowing moisture to pass quickly instead of accumulating at the adhesion interface. The dynamic adjustment of the moisture-sensitive matrix layer reduces the retention of moisture at the interface and avoids the "failure" of the wetting layer. The surface of the tape expands due to the moisture absorption of the moisture-sensitive matrix layer, increasing the contact area with the attachment surface. Through the action of hydrogen bonds and van der Waals forces, the adhesion can still be maintained within the effective range.

[0159] Therefore, the tape can ensure a firm adherence under dry conditions, avoiding falling off due to humidity changes; providing the stability required for skin attachment.

[0160] The characteristics of this tape also make it suitable for:

[0161] Adhesive tape is used for sealing packaging of high-humidity foods (such as fruits and fresh meat), and its viscosity can be adjusted according to the ambient humidity.

[0162] It can be combined with a humidity sensor to monitor humidity changes in the package and achieve dynamic sealing.

[0163] Flexible circuit board fixing: used for bonding flexible circuit boards to substrates in high humidity environments to ensure good contact.

[0164] Wearable devices: used to fix and protect wearable devices such as smart bracelets and smart glasses.

[0165] Moisture-proof decorative material fixing: Used to fix moisture-proof decorative materials in high humidity environments (such as bathrooms and kitchens).

[0166] Temporary waterproofing seal: used for temporary waterproofing seal of building exterior walls or window frames in wet weather.

[0167] Intelligent irrigation system: used to fix humidity sensors to achieve real-time monitoring of changes in farmland humidity.

[0168] Plant protection: used for plant fixation and protection, it can adjust the viscosity according to the ambient humidity to reduce damage to plants.

[0169] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An adaptive adhesive tape with humidity-responsive adhesiveness, characterized in that: include: The humidity-sensitive substrate layer is made of a polymer material having humidity-responsive properties, and the polymer material includes: Polyvinyl alcohol, mass percentage is 50%-70%; Carboxymethyl cellulose, mass percentage is 10%-20%; The dynamic cross-linking layer is evenly distributed in the humidity-sensitive substrate layer or on its surface, and is formed by a dynamic reversible cross-linking reaction between phenylboronic acid and a polyhydroxy compound, and is used to control the viscosity of the material when the humidity changes; The substrate layer is used to support the moisture-sensitive base layer, and the substrate layer is a flexible polyester film or paper substrate with a thickness of 20-100 microns.

2. The adaptive adhesive tape with humidity-responsive adhesiveness according to claim 1, characterized in that: The moisture-sensitive substrate layer further comprises: Talc or bentonite, with a mass percentage of 5%-10%, is used to enhance the mechanical strength and hygroscopicity of the moisture-sensitive substrate layer.

3. The adaptive adhesive tape with humidity-responsive adhesiveness according to claim 2, characterized in that: The dynamic cross-linking layer further comprises: Glutaraldehyde, with a mass percentage of 1%-5%, is used for preliminary cross-linking and enhancing the viscosity regulating ability of the moisture-sensitive substrate layer.

4. The adaptive adhesive tape with humidity-responsive adhesiveness according to claim 3, characterized in that: The dynamic cross-linking layer forms a high-viscosity state through rearrangement of borate cross-linking bonds when the humidity increases, and restores to a low-viscosity state through breaking of cross-linking bonds when the humidity decreases.

5. The adaptive adhesive tape with humidity-responsive adhesiveness according to claim 4, characterized in that: The surface of the humidity sensitive substrate layer has a micro-nano pore structure, which is prepared by solution-phase separation technology and is used to improve the humidity response speed.

6. The adaptive adhesive tape with humidity-responsive adhesiveness according to claim 5, characterized in that: The moisture-sensitive substrate layer further comprises: The polar modifier is a fatty acid salt or a glyceride, with a mass percentage of 0.5%-2%, and is used to improve the surface energy and viscosity adjustment performance of the moisture sensitive layer.

7. The adaptive adhesive tape with humidity-responsive adhesiveness according to claim 6, characterized in that: The moisture-sensitive base layer and the dynamic cross-linking layer are prepared by a solution blending method and are cured and formed at 40-60°C.

8. The adaptive adhesive tape with humidity-responsive adhesiveness according to claim 7, characterized in that: The dynamic cross-linking layer is formed by the reaction of 2%-5% by mass of phenylboric acid with the polyhydroxy compound in the moisture-sensitive matrix.

9. A method for preparing the adaptive adhesive tape with humidity-responsive adhesiveness according to claim 8, characterized in that: The following steps are involved: 1) Solution mixing: Dissolve polyvinyl alcohol in 80-90°C water and stir until completely dissolved to form a transparent solution; After cooling to 40-50°C, add carboxymethyl cellulose and continue stirring to form a uniform moisture-sensitive matrix solution; Add the reinforcing ingredient talc or bentonite to the solution and stir at high speed until it is completely dispersed; Phenylboronic acid and glutaraldehyde were added and stirred at room temperature to partially initiate a preliminary cross-linking reaction; Finally, a polar modifier is added to further enhance the moisture-sensitive viscosity adjustment performance of the solution; 2) Substrate treatment and coating: Choose a flexible polyester film or paper substrate with a thickness of 20-100 microns, and use plasma cleaning or surface chemical treatment to enhance the adhesion of the substrate; The mixed wet-sensitive solution is evenly coated on the surface of the substrate by a casting method or a spraying method, and the coating thickness of the wet-sensitive layer is controlled to be 50-100 microns; 3) Surface treatment: spraying phenylboric acid solution on the coated moisture-sensitive substrate layer to further form a dynamic cross-linking layer; A volatile porogen is introduced on the surface of the moisture sensitive layer, and a micro-nano pore structure is formed in the subsequent drying process through solution-phase separation technology to improve the response speed of the moisture sensitive layer; 4) Curing and molding: Use hot air drying equipment to perform low-temperature curing at 40-60°C to gradually evaporate the moisture in the moisture-sensitive matrix layer and complete the formation of a dynamic cross-linking network; During the curing process, glutaraldehyde undergoes further covalent crosslinking with polyvinyl alcohol or carboxymethyl cellulose to ensure the mechanical stability of the moisture-sensitive layer; After curing, the tape is left to stand at room temperature to optimize the structural uniformity and performance stability of the dynamically cross-linked layer; 5) Finished product cutting: The cured moisture-sensitive tape is cut according to actual application requirements, and finally an adaptive tape with humidity-responsive viscosity is obtained.

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