Solvent-resistant, soft-feeling, strong-adhesion polyurethane waterproofing agent, preparation method and application thereof

Abstract

The application discloses a solvent-resistant, soft-feeling and strong-adhesion polyurethane waterproof agent, a preparation method and application thereof. The polyurethane waterproof agent is a mixture of a water-based polyurethane emulsion, gamma-glycidyl ether oxypropyl trimethoxysilane and water, and the mass ratio of the three is 100:20-50:10-100. The preparation method is simple mixing of the three. The application is that: the polyester fabric treated by plasma is immersed in the solvent-resistant, soft-feeling and strong-adhesion polyurethane waterproof agent, one-dip-one-roll is carried out through a mangle, a polyurethane coating liquid is coated on the surface after heat setting, and a waterproof coating fabric without white creases is prepared after heat curing. The solvent-resistant, soft-feeling and strong-adhesion polyurethane waterproof agent can significantly enhance the interface adhesion between the waterproof layer and the fabric substrate and between the waterproof layer and the polyurethane coating, and can eliminate the white creases and other defects caused by the weak interface. The preparation method is simple and easy to implement, and the application prospect is wide.

Description

Technical Field

[0001] This invention belongs to the field of functional finishing technology of textiles, and relates to a solvent-resistant, soft-feeling, and strongly adhesive polyurethane waterproofing agent, its preparation method, and its application. Background Technology

[0002] In the fields of outdoor equipment and industrial protection, the performance of waterproof tent fabrics highly depends on the synergistic effect of the waterproof finishing of the fabric substrate and subsequent functional coatings. Traditional processes have long relied on fluorinated waterproofing agents (such as C6 and C8 types), which impart excellent waterproof, oil-repellent, abrasion-resistant, and durable properties to the fabric. However, fluorinated compounds degrade in the natural environment, releasing per- and polyfluoroalkyl substances (PFAS). These substances are bioaccumulative and ecotoxicological, posing potential threats to human health and the environment. With increasingly stringent global environmental regulations and rising consumer demand for sustainable products, the industry urgently needs to shift towards fluorine-free, environmentally friendly alternatives.

[0003] Currently, environmentally friendly fluorine-free waterproofing agents, represented by silicone, acrylate, and polyurethane, have become a focus of research and application due to their low toxicity and biodegradability. However, in practical applications, especially when combined with subsequent oil-based polyurethane (PU) functional coatings, these fluorine-free waterproofing agents are prone to significant "white marks" at the interface. The root cause of this problem lies in the poor solvent resistance of conventional fluorine-free waterproofing agents. During the coating process, solvents such as toluene and DMF in the PU coating solution can penetrate, swell, and even partially dissolve components in the waterproof layer, leading to the formation of a weak boundary layer at the interface. When the fabric is subjected to external forces such as bending and rubbing, the stress concentration at the interface easily triggers microscopic separation, and light scatters at the cracks, thus appearing as "white marks." In contrast, traditional fluorine-containing waterproofing agents have excellent water and oil repellency, making it difficult for oily solvents in the PU coating solution to penetrate the waterproofing agent layer, thus preventing white marks.

[0004] Among various fluorine-free waterproofing agents, waterborne polyurethane waterproofing agents are often chosen due to their molecular structure being similar to that of subsequent PU coatings, aiming to achieve better interlayer compatibility. However, polyurethane molecular chains are rich in polar groups and have high compatibility with solvents such as toluene and DMF, causing the coating to easily swell or even dissolve, subsequently detaching from the fabric and easily showing white marks under external force. To improve its solvent resistance, a common strategy is to increase the crosslinking density of the molecular chains; however, excessive crosslinking can lead to a brittle and hard coating that loses its flexibility. In addition, rigid cyclic structures or large side groups can be introduced into the polymer chains to enhance the coating's resistance to swelling. However, such rigid structures significantly increase the rigidity of the molecular chains, reducing their flexibility and potentially causing brittle fracture under external force, negatively impacting its feel and ultimate resistance to "white marks."

[0005] Therefore, there is an urgent need to develop a solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent to solve the problems of white creases and poor hand feel in waterproof coated fabrics. Summary of the Invention

[0006] To address the problem of white marks easily appearing on fabrics when fluorine-free waterproofing agents are used in combination with PU coatings in existing technologies, the purpose of this invention is to provide a solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent, its preparation method, and its application.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent, characterized in that it is a mixture of water-based polyurethane emulsion, γ-glycidyl etheroxypropyltrimethoxysilane, and water; The mass ratio of waterborne polyurethane emulsion, γ-glycidyl etheroxypropyltrimethoxysilane and water is 100:20-50:10-100.

[0008] The structural formula of waterborne polyurethane is: .

[0009] The preparation method of waterborne polyurethane emulsion is as follows: First, under nitrogen protection, polyol, isocyanate, hydroxyl silicone oil and catalyst are mixed and heated and stirred at 65°C for 2-3 hours to form polyurethane prepolymer; then the temperature is lowered to 40-45°C and chain extender and acetone are added, and the temperature is raised to 50-70°C to continue the reaction for 0.5-2 hours; then the temperature is lowered to 30-35°C and crosslinking agent is added, and the temperature is raised to 40-70°C to react for 1-3 hours; then the temperature is lowered to 30-40°C and 18-phenyloctadecyl alcohol is added, and the temperature is raised to 50-60°C to react for 1-3 hours; after cooling to room temperature, neutralizing agent and deionized water are added to obtain reaction solution, and the reaction solution is added to deionized water for emulsification for 1 hour under high-speed stirring in a disperser at 6000 r / min; finally, residual acetone in the system is removed by rotary evaporation, and then deionized water is added for emulsification to obtain waterborne polyurethane emulsion.

[0010] The number average molecular weight of the hydroxyl silicone oil is 1000-5000; the polyol is one or more of polyester polyol and polyether polyol; the isocyanate is one or more of toluene diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate and isophorone diisocyanate; the catalyst is dibutyltin dilaurate; the neutralizing agent is triethylamine; the chain extender is one or more of dimethylolpropionic acid, dimethylolbutyric acid and 1,4-butanediol; and the crosslinking agent is one or more of trimethylolpropane, castor oil, pentaerythritol and ethylene glycol.

[0011] The raw materials used in the preparation of waterborne polyurethane emulsions, according to their mass percentages, are as follows: Polyols 10-40%; Isocyanate 10-20%; Hydroxysilicone oil 1-7%; Catalyst 0.01-0.1%; 1-3% of 18-phenyloctadecyl alcohol; Chain extender 1-4%; Acetone 8-15%; Crosslinking agent 0.01-1%; Neutralizing agent 1-4%; Deionized water balance.

[0012] A method for preparing a solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent, characterized in that: an aqueous polyurethane emulsion, γ-glycidoxypropyltrimethoxysilane, and water are mixed to obtain a solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent.

[0013] An application of a solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent, characterized in that it is used to prepare waterproof coated fabrics without white creases.

[0014] The specific preparation method of the waterproof coating fabric without white creases is as follows: the polyester fabric after plasma treatment is immersed in a polyurethane waterproofing agent that is solvent-resistant, soft to the touch, and has strong adhesion. It is then dipped and rolled once by a rolling mill. After heat setting, a polyurethane coating liquid is applied to the surface. After heat curing, the waterproof coating fabric without white creases is obtained.

[0015] The dry weight gain of the fabric after being coated with polyurethane coating liquid is 7-8 g / m2.

[0016] The plasma treatment time is 1-2 minutes, the atmosphere is air, and the pressure is normal pressure; the heat setting temperature is 150-180℃, and the time is 1-2 minutes; the heat curing temperature is 120-130℃, and the time is 1-2 minutes.

[0017] Mechanism of Invention: This invention first uses 18-phenyloctadecyl alcohol, which has a unique "hanging" structure, to chemically modify polyurethane. One end of this molecule is chemically bonded to the polyurethane backbone, while the octadecyl chain extending from the other end can spontaneously and orderly stack within the coating, forming a dense solvent-repellent physical barrier layer that significantly delays the penetration and diffusion of solvents such as toluene and DMF. Simultaneously, the benzene ring at the end of the long chain, through strong intermolecular interactions such as π-π stacking, constructs reversible "physical cross-linking points" between the polyurethane chains, thereby greatly improving the coating's resistance to swelling and structural integrity. This synergistic design of "long-chain barrier" and "end-strength reinforcement" ensures that the material achieves excellent solvent resistance while maximizing the retention of the inherent flexibility of polyurethane due to the rigid benzene ring being far from the backbone.

[0018] This invention uses 18-phenyloctadecyl alcohol to chemically modify polyurethane. If shorter alkyl chains (such as 8-phenyloctanol or 12-phenyldodecyl alcohol) are used, the crystallinity or packing density is insufficient, making it difficult to form a dense and stable physical barrier layer. The barrier effect on toluene / DMF is limited, the physical crosslinking points are weak, and the improvement of interchain forces is not significant. If longer alkyl chains (such as 22-phenyldodecyl alcohol) are used, the synthesis difficulty and cost increase dramatically, and the long-chain crystalline regions become hard fillers, completely sacrificing flexibility.

[0019] In the preparation of waterborne polyurethane emulsions, incorporating hydroxyl silicone oil as a soft segment into the main chain significantly enhances chain mobility. The flexibility of the silicone oil provides a buffer for the rigid crystalline regions of 18-phenyloctadecyl alcohol, preventing excessive growth that could lead to brittleness and optimizing the balance between rigidity and flexibility. The siloxane structure in the main chain exhibits excellent compatibility with the polysiloxane network formed by γ-glycidoxypropyltrimethoxysilane, improving interfacial bonding and stability.

[0020] This invention incorporates γ-glycidoxypropyltrimethoxysilane. This component hydrolyzes and self-condenses in an aqueous environment to form a polysiloxane network that interweaves with the aforementioned polyurethane network. The low surface energy of organosilicon imparts durable oil-repellent properties to the coating. More importantly, its abundant active silanol and epoxy groups can chemically react with functional groups on the polyester fabric surface and the polyurethane coating to form stable covalent bonds. This fundamentally and significantly enhances the interfacial adhesion between the waterproof layer and the fabric substrate, as well as between the waterproof layer and the polyurethane coating, eliminating defects such as white marks caused by weak interfaces.

[0021] The mass ratio of γ-glycidoxypropyltrimethoxysilane to aqueous polyurethane emulsion is 20-50:100. If the content of γ-glycidoxypropyltrimethoxysilane is too low, it cannot form sufficient covalent bonds with the polyester fabric, resulting in insignificant adhesion enhancement, an incomplete polysiloxane network, and insufficient manifestation of low surface energy characteristics. If the content of γ-glycidoxypropyltrimethoxysilane is too high, its strong self-condensation tendency and incompatibility with polyurethane will disrupt the system balance. A large amount of self-polymerized γ-glycidoxypropyltrimethoxysilane cannot effectively migrate to the fabric interface and may instead form brittle silicon clusters within the coating, becoming stress concentration points and weak points. Beneficial effects

[0022] (1) The present invention provides a solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent. Under normal conditions, the waterproofing performance is grade 4-5, and after 5 rubs with toluene, the waterproofing performance is grade 4-5; the softness to the touch is grade 1-2; under normal conditions, the adhesion of the waterproofing agent layer is grade 0-1, and after 5 rubs with toluene, the adhesion of the waterproofing agent layer is grade 0-1; when the polyurethane waterproofing agent is used in combination with the PU coating, the fabric will not show white marks after repeated folding and rubbing 100 times.

[0023] (2) In the preparation process of fluorine-free waterproofing agent, hydroxyl silicone oil is introduced into the polyurethane backbone to improve the film-forming flexibility of the waterproofing agent.

[0024] (3) The present invention uses a fluorine-free waterproofing agent to replace the traditional fluorine-containing waterproofing agent, with no VOC emissions, ensuring the production and application of the waterproofing agent and the eco-friendly nature of textiles.

[0025] The present invention will be further described below with reference to the embodiments. Detailed Implementation

[0026] The testing methods for the performance metrics involved in the following embodiments are as follows: 1. White mark test: Fold and rub the waterproof coated fabric without white marks more than 100 times and observe the white marks.

[0027] 2. Adhesion: The plasma-treated polyester fabric is immersed in a solvent-resistant, soft-to-the-hand, and highly adhesive polyurethane waterproofing agent. The fabric is then subjected to a single dip and roll process using a rolling mill, followed by heat setting to obtain the waterproof fabric. The adhesion of the waterproof fabric under normal conditions (without friction) and after five cycles of toluene rubbing, as well as the adhesion of the waterproof coating fabric without white creases under normal conditions, are tested according to the cross-cut test method in standard GB / T 9286-2021 "Paints and Varnishes, Paint Films".

[0028] 3. Waterproof performance: The waterproof performance of the waterproof fabric was tested under normal conditions and after 5 rubs with toluene, according to GB / T 4745-2012 Test and evaluation of waterproof performance of textiles - water immersion method.

[0029] 4. Hand feel test: The softness of waterproof fabric is divided into 6 levels: 1 is very soft, 2 is soft, 3 is relatively soft, 4 is relatively stiff, 5 is stiff, and 6 is very stiff.

[0030] In this embodiment, the plasma treatment time for the polyester fabric is 2 minutes, the atmosphere is air, and the pressure is atmospheric pressure.

[0031] The sources of some of the substances involved in the following embodiments are as follows: Polyester polyol: Manufacturer is Shenzhen Guanghua Weiye Co., Ltd., brand name is PCL220.

[0032] Polyether polyol: Manufacturer is Shanghai Maclean Biochemical Technology Co., Ltd., brand name is P816810.

[0033] Polyurethane coating liquid: includes polyurethane prepolymer and curing agent, manufactured by Zhangjiagang Oriental High-tech Polyurethane Co., Ltd. The polyurethane prepolymer is graded UM-3000 and UM-50F, which are mixed in a mass ratio of 1:1. The curing agent is graded DN-75.

[0034] Example 1 A method for preparing a solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent, the specific steps of which are as follows: (1) Preparation of waterborne polyurethane emulsion; (1.1) Under nitrogen protection, polyester polyol, isocyanate (toluene diisocyanate and diphenylmethane diisocyanate in a molar ratio of 1:1), hydroxyl silicone oil with a number average molecular weight of 1000 and dibutyltin dilaurate are mixed and heated and stirred at 65°C for 2 hours to form a polyurethane prepolymer. (1.2) After the reaction in step (1.1) is completed, the temperature is lowered to 40°C, chain extender (dimethylolpropionic acid and 1,4-butanediol in a molar ratio of 1:2) and acetone are added, and the temperature is raised to 50°C to continue the reaction for 0.5 h. (1.3) After the reaction in step (1.2) is completed, the temperature is lowered to 30°C, a crosslinking agent (trimethylolpropane and castor oil, molar ratio of 1:5) is added, and the temperature is raised to 40°C for 1 hour. (1.4) After the reaction in step (1.3) is completed, cool down to 30°C, add 18-phenyloctadecyl alcohol, and heat up to 50°C to react for 1 hour; (1.5) After the reaction in step (1.4) is cooled to room temperature, triethylamine and deionized water are added, and the reaction solution is emulsified in deionized water for 1 hour under high-speed stirring in a disperser at a speed of 6000 r / min. (1.6) The residual acetone in the system of step (1.5) was removed by rotary evaporation, and then deionized water was added for emulsification to obtain an aqueous polyurethane emulsion. The amounts of the above-mentioned raw materials used in preparation, according to the mass percentage, are as follows: polyester polyol 10%, isocyanate 10%, hydroxy silicone oil 1%, dibutyltin dilaurate 0.01%, 18-phenyloctadecyl alcohol 1%, chain extender 1%, acetone 8%, crosslinking agent 0.01%, triethylamine 1%, and deionized water balance; The structural formula of waterborne polyurethane is: ; (2) A water-based polyurethane emulsion, γ-glycidyl etheroxypropyltrimethoxysilane and water are mixed in a mass ratio of 100:20:10 to obtain a polyurethane waterproofing agent that is solvent-resistant, soft to the touch and has strong adhesion.

[0035] The polyester fabric, after plasma treatment, is immersed in a solvent-resistant, soft-to-the-touch, and highly adhesive polyurethane waterproofing agent. It is then subjected to a single immersion and rubbing process using a rolling mill with a pressure of 0.4 MPa, a speed of 15 m / s, and a liquid retention rate of 30%. The fabric is then heat-set at 150°C for 2 minutes to obtain the waterproof fabric. Under normal conditions, the waterproof performance is grade 4, and the adhesion is grade 1. After five cycles of toluene rubbing, the waterproof performance remains grade 4, and the adhesion remains grade 1. The softness of the waterproof fabric is grade 1.

[0036] Example 2 A method for preparing a solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent, the specific steps of which are as follows: (1) Preparation of waterborne polyurethane emulsion; (1.1) Under nitrogen protection, polyester polyol, isocyanate (toluene diisocyanate and dicyclohexylmethane diisocyanate in a molar ratio of 1:1), hydroxyl silicone oil with a number average molecular weight of 2000 and dibutyltin dilaurate are mixed and heated and stirred at 65°C for 2 hours to form a polyurethane prepolymer. (1.2) After the reaction in step (1.1) is completed, the temperature is lowered to 42°C, chain extender (dimethylolbutyric acid and 1,4-butanediol in a molar ratio of 1:2) and acetone are added, and the temperature is raised to 55°C to continue the reaction for 1 hour. (1.3) After the reaction in step (1.2) is completed, the temperature is lowered to 33°C, and a crosslinking agent (trimethylolpropane and pentaerythritol in a molar ratio of 1:5) is added. The temperature is then raised to 50°C and the reaction is allowed to proceed for 1.2 h. (1.4) After the reaction in step (1.3) is completed, the temperature is lowered to 32°C, 18-phenyloctadecyl alcohol is added, and the temperature is raised to 52°C for 1.5 h. (1.5) After the reaction in step (1.4) is cooled to room temperature, triethylamine and deionized water are added, and the reaction solution is emulsified in deionized water for 1 hour under high-speed stirring in a disperser at a speed of 6000 r / min. (1.6) The residual acetone in the system of step (1.5) was removed by rotary evaporation, and then deionized water was added for emulsification to obtain an aqueous polyurethane emulsion. The amounts of the above-mentioned raw materials used in preparation, according to the mass percentage, are as follows: polyester polyol 15%, isocyanate 12%, hydroxyl silicone oil 3%, dibutyltin dilaurate 0.03%, 18-phenyloctadecyl alcohol 1.5%, chain extender 1.5%, acetone 10%, crosslinking agent 0.1%, triethylamine 2%, and deionized water balance; The structural formula of waterborne polyurethane is: ; (2) A water-based polyurethane emulsion, γ-glycidyl etheroxypropyltrimethoxysilane and water are mixed in a mass ratio of 100:20:50 to obtain a polyurethane waterproofing agent that is solvent-resistant, soft to the touch and has strong adhesion.

[0037] The polyester fabric, after plasma treatment, is immersed in a solvent-resistant, soft-to-the-touch, and highly adhesive polyurethane waterproofing agent. It is then subjected to a single immersion and rubbing process using a rolling mill at a pressure of 0.4 MPa and a speed of 15 m / s, with a liquid retention rate of 32%. The fabric is then heat-set at 160°C for 2 minutes to obtain the waterproof fabric. Under normal conditions, the waterproof performance is grade 4, and the adhesion is grade 0. After five cycles of toluene rubbing, the waterproof performance remains grade 4, and the adhesion remains grade 0. The softness of the waterproof fabric is grade 1.

[0038] Example 3 A method for preparing a solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent, the specific steps of which are as follows: (1) Preparation of waterborne polyurethane emulsion; (1.1) Under nitrogen protection, polyether polyol, isocyanate (toluene diisocyanate and hexamethylene diisocyanate in a molar ratio of 1:1), hydroxyl silicone oil with a number average molecular weight of 3000 and dibutyltin dilaurate are mixed and heated and stirred at 65°C for 2 hours to form a polyurethane prepolymer. (1.2) After the reaction in step (1.1) is completed, the temperature is lowered to 42°C, chain extender (dimethylolpropionic acid and 1,4-butanediol in a molar ratio of 1:2) and acetone are added, and the temperature is raised to 55°C to continue the reaction for 1.5 h. (1.3) After the reaction in step (1.2) is completed, the temperature is lowered to 34°C, a crosslinking agent (trimethylolpropane and ethylene glycol in a molar ratio of 1:5) is added, and the temperature is raised to 60°C for 2 hours. (1.4) After the reaction in step (1.3) is completed, the temperature is lowered to 35°C, 18-phenyloctadecyl alcohol is added, and the temperature is raised to 55°C for 2 hours. (1.5) After the reaction in step (1.4) is cooled to room temperature, triethylamine and deionized water are added, and the reaction solution is emulsified in deionized water for 1 hour under high-speed stirring in a disperser at a speed of 6000 r / min. (1.6) The residual acetone in the system of step (1.5) was removed by rotary evaporation, and then deionized water was added for emulsification to obtain an aqueous polyurethane emulsion. The amounts of the above-mentioned raw materials used in preparation, according to the mass percentage, are as follows: polyether polyol 20%, isocyanate 16%, hydroxyl silicone oil 4%, dibutyltin dilaurate 0.07%, 18-phenyloctadecyl alcohol 2%, chain extender 2%, acetone 12%, crosslinking agent 0.5%, triethylamine 3%, and deionized water balance. The structural formula of waterborne polyurethane is: ; (2) A water-based polyurethane emulsion, γ-glycidyl etheroxypropyltrimethoxysilane and water are mixed in a mass ratio of 100:50:20 to obtain a polyurethane waterproofing agent that is solvent-resistant, soft to the touch and has strong adhesion.

[0039] The polyester fabric, after plasma treatment, is immersed in a solvent-resistant, soft-to-the-touch, and highly adhesive polyurethane waterproofing agent. It is then subjected to a single immersion and rubbing process using a rolling mill at a pressure of 0.4 MPa and a speed of 15 m / s, with a liquid retention rate of 34%. The fabric is then heat-set at 165°C for 1.5 minutes to obtain the waterproof fabric. Under normal conditions, the waterproof performance is grade 5, and the adhesion is grade 0. After five cycles of toluene rubbing, the waterproof performance remains grade 5, and the adhesion is grade 0. The softness of the waterproof fabric is grade 2.

[0040] Example 4 A method for preparing a solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent, the specific steps of which are as follows: (1) Preparation of waterborne polyurethane emulsion; (1.1) Under nitrogen protection, polyether polyol, isocyanate (toluene diisocyanate and isophorone diisocyanate in a molar ratio of 1:1), hydroxyl silicone oil with a number average molecular weight of 3500 and dibutyltin dilaurate are mixed and heated and stirred at 65°C for 3 hours to form a polyurethane prepolymer. (1.2) After the reaction in step (1.1) is completed, the temperature is lowered to 44°C, chain extender (dimethylolbutyric acid and 1,4-butanediol in a molar ratio of 1:2) and acetone are added, and the temperature is raised to 60°C to continue the reaction for 1.5 h. (1.3) After the reaction in step (1.2) is completed, the temperature is lowered to 34°C, and a crosslinking agent (trimethylolpropane, castor oil and pentaerythritol in a molar ratio of 1:2:3) is added. The temperature is then raised to 65°C and the reaction is allowed to proceed for 2.5 hours. (1.4) After the reaction in step (1.3) is completed, the temperature is lowered to 35°C, 18-phenyloctadecyl alcohol is added, and the temperature is raised to 58°C for 2.8 h. (1.5) After the reaction in step (1.4) is cooled to room temperature, triethylamine and deionized water are added, and the reaction solution is emulsified in deionized water for 1 hour under high-speed stirring in a disperser at a speed of 6000 r / min. (1.6) The residual acetone in the system of step (1.5) was removed by rotary evaporation, and then deionized water was added for emulsification to obtain an aqueous polyurethane emulsion. The amounts of the above-mentioned raw materials used in preparation, according to the mass percentage, are as follows: polyether polyol 30%, isocyanate 18%, hydroxyl silicone oil 6%, dibutyltin dilaurate 0.08%, 18-phenyloctadecyl alcohol 2.5%, chain extender 3%, acetone 14%, crosslinking agent 0.8%, triethylamine 3.5%, and deionized water balance; The structural formula of waterborne polyurethane is: ; (2) A water-based polyurethane emulsion, γ-glycidyl etheroxypropyltrimethoxysilane and water are mixed in a mass ratio of 100:30:10 to obtain a polyurethane waterproofing agent that is solvent-resistant, soft to the touch and has strong adhesion.

[0041] The polyester fabric, after plasma treatment, is immersed in a solvent-resistant, soft-to-the-touch, and highly adhesive polyurethane waterproofing agent. It is then subjected to a single immersion and rubbing process using a rolling mill at a pressure of 0.4 MPa and a speed of 15 m / s, with a liquid retention rate of 37%. The fabric is then heat-set at 170°C for 1 minute to obtain the waterproof fabric. Under normal conditions, the waterproof performance is grade 5, and the adhesion is grade 1. After five cycles of toluene rubbing, the waterproof performance remains grade 5, and the adhesion remains grade 1. The softness of the waterproof fabric is grade 1.

[0042] Example 5 A method for preparing a solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent, the specific steps of which are as follows: (1) Preparation of waterborne polyurethane emulsion; (1.1) Under nitrogen protection, polyols (polyester polyol and polyether polyol in a molar ratio of 1:1), isocyanates (toluene diisocyanate, diphenylmethane diisocyanate and dicyclohexylmethane diisocyanate in a molar ratio of 1:1:1), hydroxyl silicone oil with a number average molecular weight of 5000 and dibutyltin dilaurate are mixed and heated and stirred at 65°C for 3 hours to form a polyurethane prepolymer; (1.2) After the reaction in step (1.1) is completed, the temperature is lowered to 45°C, chain extender (dimethylolpropionic acid, dimethylolbutyric acid and 1,4-butanediol in a molar ratio of 1:1:4) and acetone are added, and the temperature is raised to 70°C to continue the reaction for 2 hours. (1.3) After the reaction in step (1.2) is completed, the temperature is lowered to 35°C, and a crosslinking agent (trimethylolpropane, castor oil, pentaerythritol and ethylene glycol in a molar ratio of 1:1:2:2) is added. The temperature is then raised to 70°C and reacted for 3 hours. (1.4) After the reaction in step (1.3) is completed, the temperature is lowered to 40°C, 18-phenyloctadecyl alcohol is added, and the temperature is raised to 60°C for 3 hours. (1.5) After the reaction in step (1.4) is cooled to room temperature, triethylamine and deionized water are added, and the reaction solution is emulsified in deionized water for 1 hour under high-speed stirring in a disperser at a speed of 6000 r / min. (1.6) The residual acetone in the system of step (1.5) was removed by rotary evaporation, and then deionized water was added for emulsification to obtain an aqueous polyurethane emulsion. The amounts of the above-mentioned raw materials used in preparation, according to the mass percentage, are as follows: polyol 40%, isocyanate 20%, hydroxy silicone oil 7%, dibutyltin dilaurate 0.1%, 18-phenyloctadecyl alcohol 3%, chain extender 4%, acetone 15%, crosslinking agent 1%, triethylamine 4%, and deionized water balance. The structural formula of waterborne polyurethane is: ; (2) A water-based polyurethane emulsion, γ-glycidyl etheroxypropyltrimethoxysilane and water are mixed in a mass ratio of 100:20:80 to obtain a polyurethane waterproofing agent that is solvent-resistant, soft to the touch and has strong adhesion.

[0043] The polyester fabric, after plasma treatment, is immersed in a solvent-resistant, soft-to-the-touch, and highly adhesive polyurethane waterproofing agent. It is then subjected to a single immersion and rubbing process using a rolling mill at a pressure of 0.4 MPa, a speed of 15 m / s, and a liquid retention rate of 40%. The fabric is then heat-set at 180°C for 1 minute to obtain the waterproof fabric. Under normal conditions, the waterproof performance is grade 5, and the adhesion is grade 0. After five cycles of toluene rubbing, the waterproof performance remains grade 5, and the adhesion is grade 0. The softness of the waterproof fabric is grade 2. Example 6

[0044] A method for preparing a waterproof coated fabric without white creases, the specific steps of which are as follows: (1) The polyester fabric after plasma treatment was immersed in the solvent-resistant, soft-feeling, and strongly adhesive polyurethane waterproofing agent prepared in Example 1, and was dipped and rolled in one pass by a rolling mill. The pressure of the rolling mill was 0.4 MPa, the speed was 15 m / s, and the liquid content was 30%. (2) Heat set the polyester fabric after step (1) at 150℃ for 2 minutes; (3) After heat setting in step (2), the surface of the polyester fabric is coated with polyurethane coating liquid and cured at 120°C for 2 minutes to obtain a waterproof coated fabric without white creases; the dry weight gain of the fabric after being coated with polyurethane coating liquid is 7g / m2.

[0045] The final waterproof fabric with no white creases has a coating adhesion rating of 0 and shows no white marks after being repeatedly folded and rubbed 200 times.

[0046] Example 7 A method for preparing a waterproof coated fabric without white creases, the specific steps of which are as follows: (1) The polyester fabric after plasma treatment was immersed in the solvent-resistant, soft-feeling, and strong-adhesion polyurethane waterproofing agent prepared in Example 2, and was dipped and rolled in one pass by a rolling mill. The pressure of the rolling mill was 0.4 MPa, the speed was 15 m / s, and the liquid carry-over rate was 32%. (2) Heat set the polyester fabric after step (1) at 160℃ for 2 minutes; (3) After heat setting in step (2), the surface of the polyester fabric is coated with polyurethane coating liquid and cured at 122℃ for 2 minutes to obtain a waterproof coated fabric without white creases; the dry weight gain of the fabric after being coated with polyurethane coating liquid is 7g / m2.

[0047] The final waterproof fabric with no white creases has a coating adhesion rating of 0 and shows no white marks after being repeatedly folded and rubbed 200 times.

[0048] Example 8 A method for preparing a waterproof coated fabric without white creases, the specific steps of which are as follows: (1) The polyester fabric after plasma treatment was immersed in the solvent-resistant, soft-feeling, and strongly adhesive polyurethane waterproofing agent prepared in Example 3. The fabric was then dipped and rolled in one pass through a rolling mill. The rolling mill pressure was 0.4 MPa, the speed was 15 m / s, and the liquid carry-over rate was 34%. (2) Heat set the polyester fabric after step (1) at 165℃ for 1.5 min; (3) After heat setting in step (2), the surface of the polyester fabric is coated with polyurethane coating liquid and heat cured at 125°C for 1.5 min to obtain a waterproof coated fabric without white creases; the dry weight gain of the fabric after being coated with polyurethane coating liquid is 8 g / m2.

[0049] The final waterproof fabric with no white creases has a coating adhesion rating of 0 and shows no white marks after being repeatedly folded and rubbed 200 times.

[0050] Example 9 A method for preparing a waterproof coated fabric without white creases, the specific steps of which are as follows: (1) The polyester fabric after plasma treatment was immersed in the solvent-resistant, soft-feeling, and strongly adhesive polyurethane waterproofing agent prepared in Example 4, and was dipped and rolled in one pass by a rolling mill. The pressure of the rolling mill was 0.4 MPa, the speed was 15 m / s, and the liquid carry-over rate was 37%. (2) Heat set the polyester fabric after step (1) at 170℃ for 1 min; (3) After heat setting in step (2), the surface of the polyester fabric is coated with polyurethane coating liquid and cured at 127°C for 1 minute to obtain a waterproof coated fabric without white creases; the dry weight gain of the fabric after being coated with polyurethane coating liquid is 7g / m2.

[0051] The final waterproof fabric with no white creases has a coating adhesion of level 1, and no white marks are visible after 200 repeated folding and rubbing.

[0052] Example 10 A method for preparing a waterproof coated fabric without white creases, the specific steps of which are as follows: (1) The polyester fabric after plasma treatment was immersed in the solvent-resistant, soft-feeling, and strongly adhesive polyurethane waterproofing agent prepared in Example 5, and was dipped and rolled in one pass by a rolling mill. The pressure of the rolling mill was 0.4 MPa, the speed was 15 m / s, and the liquid content was 40%. (2) Heat set the polyester fabric after step (1) at 180℃ for 1 min; (3) After heat setting in step (2), the surface of the polyester fabric is coated with polyurethane coating liquid and cured at 130°C for 1 minute to obtain a waterproof coated fabric without white creases; the dry weight gain of the fabric after being coated with polyurethane coating liquid is 8g / m2.

[0053] The final waterproof fabric with no white creases has a coating adhesion rating of 0 and shows no white marks after being repeatedly folded and rubbed 200 times.

Claims

1. A solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent, characterized in that: It is a mixture of aqueous polyurethane emulsion, γ-glycidyl etheroxypropyltrimethoxysilane and water; The mass ratio of waterborne polyurethane emulsion, γ-glycidyl etheroxypropyltrimethoxysilane and water is 100:20-50:10-100.

2. The solvent-resistant, soft-feeling, and strongly adhesive polyurethane waterproofing agent according to claim 1, characterized in that: The structural formula of waterborne polyurethane is: 。 3. A solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent according to claim 1 or 2, characterized in that, The preparation method of waterborne polyurethane emulsion is as follows: First, under nitrogen protection, polyol, isocyanate, hydroxyl silicone oil and catalyst are mixed and heated and stirred at 65°C for 2-3 hours to form polyurethane prepolymer; then the temperature is lowered to 40-45°C and chain extender and acetone are added, and the temperature is raised to 50-70°C to continue the reaction for 0.5-2 hours; then the temperature is lowered to 30-35°C and crosslinking agent is added, and the temperature is raised to 40-70°C to react for 1-3 hours; then the temperature is lowered to 30-40°C and 18-phenyloctadecyl alcohol is added, and the temperature is raised to 50-60°C to react for 1-3 hours; after cooling to room temperature, neutralizing agent and deionized water are added to obtain reaction solution, and the reaction solution is added to deionized water for emulsification for 1 hour under high-speed stirring in a disperser at 6000 r / min; finally, residual acetone in the system is removed by rotary evaporation, and then deionized water is added for emulsification to obtain waterborne polyurethane emulsion.

4. The polyurethane waterproofing agent with solvent resistance, soft feel, and strong adhesion according to claim 3, characterized in that, The number average molecular weight of the hydroxyl silicone oil is 1000-5000; the polyol is one or more of polyester polyol and polyether polyol; the isocyanate is one or more of toluene diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate and isophorone diisocyanate; the catalyst is dibutyltin dilaurate; the neutralizing agent is triethylamine; the chain extender is one or more of dimethylolpropionic acid, dimethylolbutyric acid and 1,4-butanediol; and the crosslinking agent is one or more of trimethylolpropane, castor oil, pentaerythritol and ethylene glycol.

5. The polyurethane waterproofing agent with solvent resistance, soft feel, and strong adhesion according to claim 3, characterized in that, The raw materials used in the preparation of waterborne polyurethane emulsions, according to their mass percentages, are as follows: Polyols 10-40%; Isocyanate 10-20%; Hydroxysilicone oil 1-7%; Catalyst 0.01-0.1%; 1-3% of 18-phenyloctadecyl alcohol; Chain extender 1-4%; Acetone 8-15%; Crosslinking agent 0.01-1%; Neutralizing agent 1-4%; Deionized water balance.

6. A method for preparing a solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent as described in any one of claims 1-5, characterized in that: A water-based polyurethane emulsion, γ-glycidyl etheroxypropyltrimethoxysilane, and water are mixed to obtain a polyurethane waterproofing agent that is solvent-resistant, soft to the touch, and has strong adhesion.

7. The application of a solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent as described in any one of claims 1-5, characterized in that: Used to prepare waterproof coated fabrics without white creases.

8. The application of the solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent according to claim 7, characterized in that, The specific preparation method of the waterproof coating fabric without white creases is as follows: the polyester fabric after plasma treatment is immersed in a polyurethane waterproofing agent that is solvent-resistant, soft to the touch, and has strong adhesion. It is then dipped and rolled by a rolling mill. After heat setting, a polyurethane coating liquid is applied to the surface. After heat curing, the waterproof coating fabric without white creases is obtained.

9. The application of the solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent according to claim 8, characterized in that, The dry weight gain of the fabric coated with polyurethane coating liquid is 7-8 g / m². 2 .

10. The application of the solvent-resistant, soft-to-the-touch, and strongly adhesive polyurethane waterproofing agent according to claim 8, characterized in that, The plasma treatment time is 1-2 minutes, the atmosphere is air, and the pressure is normal pressure; the heat setting temperature is 150-180℃, and the time is 1-2 minutes; the heat curing temperature is 120-130℃, and the time is 1-2 minutes.

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