Halogen-free flame-retardant polyester non-woven fabric for automotive trim and preparation method thereof
High-efficiency halogen-free flame-retardant polyester nonwoven fabric was prepared by modifying organosilicon segments and polyvinyl alcohol and surface treatment of fillers. This solved the problems of flammability of polyester nonwoven fabric and toxic fumes of traditional halogen flame retardants, and achieved higher flame retardant performance and safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HUAIAN RUILIAN AUTOMOBILE TECHNOLOGY CO LTD
- Filing Date
- 2026-02-06
- Publication Date
- 2026-05-12
AI Technical Summary
Existing polyester nonwoven fabrics are flammable, and traditional halogenated flame retardants produce toxic fumes when burned, posing fire safety hazards and environmental harm, and are also subject to international environmental regulations.
By introducing organosilicon segments through the reaction of terminal hydroxyl polydimethylsiloxane and diisocyanate, followed by polyvinyl alcohol modification and esterification reaction of DDP flame retardant, and then combining polydopamine encapsulation and silane coupling agent treatment of fillers, a high-efficiency halogen-free flame-retardant polyester nonwoven fabric is formed.
It significantly improves the flame retardant properties of polyester nonwoven fabric, enhances interfacial adhesion and bonding strength, improves the density and uniformity of the coating, enhances the gas phase flame retardant effect, improves the dispersibility and stress transfer of fillers, and overcomes the problems of embrittlement and short-lasting effect of traditional halogen-free flame retardant systems.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of nonwoven fabric technology, specifically to a halogen-free flame-retardant polyester nonwoven fabric for automotive interiors and its preparation method. Background Technology
[0002] With the rapid development of the automotive industry and the increasing demands of consumers for automotive safety, environmental protection, and comfort, the functionality of automotive interior materials has become a focus of attention. Among these, flame retardancy is a key indicator for ensuring the safety of drivers and passengers. Polyester nonwoven fabric, due to its low cost, ease of processing, and good mechanical properties, is widely used in automotive interior components such as base fabrics, sound insulation pads, and headliners. However, polyester nonwoven fabric has the following drawbacks: 1. As a thermoplastic polymer, polyester nonwoven fabric has a low limiting oxygen index (LOI), making it flammable and exhibiting severe dripping, posing a significant fire hazard; 2. While traditional halogenated flame retardants (such as bromine-based and chlorine-based halogenated flame retardants) have high flame retardant efficiency, they produce large amounts of toxic and corrosive fumes and gases during combustion, causing secondary harm to personnel escape and the environment, and their use is increasingly restricted by stringent international environmental regulations.
[0003] Therefore, in order to solve the above problems, the present invention proposes a halogen-free flame-retardant polyester nonwoven fabric for automotive interiors and its preparation method. Summary of the Invention
[0004] The purpose of this invention is to provide a halogen-free flame-retardant polyester nonwoven fabric for automotive interiors and its preparation method, so as to solve the problems raised in the prior art.
[0005] To achieve the above objectives, the present invention provides the following technical solution: A method for preparing halogen-free flame-retardant polyester nonwoven fabric for automotive interiors includes the following steps: (1) Hydroxyl-terminated polydimethylsiloxane, diisocyanate and catalyst are mixed and reacted. A hydrophilic chain extender is added and the reaction continues. After the reaction, acetone is added to prepare polyurethane prepolymer. Polyvinyl alcohol was added to the polyurethane prepolymer and reacted; triethylamine was added to neutralize it, and the mixture was poured into deionized water under high-speed stirring to emulsify, thus obtaining a polyvinyl alcohol-modified polyurethane emulsion. (2) Mix polyvinyl alcohol modified polyurethane emulsion, flame retardant filler and deionized water to obtain impregnation material; (3) Immerse the polyester nonwoven fabric in the impregnating material for 15-30 minutes, take it out, and then dry and cure it to obtain halogen-free flame-retardant polyester nonwoven fabric.
[0006] Furthermore, in step (1), polyvinyl alcohol undergoes flame retardant modification. The specific process is as follows: [(6-oxo-6H-dibenzo[c,e][1,2]oxophosphoric acid-6-yl)methyl]succinic acid (DDP), polyvinyl alcohol, and the catalyst p-toluenesulfonic acid are added to dimethyl sulfoxide. After the reaction, the mixture is precipitated, washed, and dried to obtain flame retardant modified polyvinyl alcohol. The mass ratio of polyvinyl alcohol, DDP, and the catalyst p-toluenesulfonic acid is 1:(0.25-0.5):(0.001-0.003). The ratio of polyvinyl alcohol to dimethyl sulfoxide is 1g:(10-20)mL; The reaction process conditions are as follows: under nitrogen protection and at a temperature of 110-120℃, the reaction is carried out for 6-10 hours. During the reaction, the generated water is continuously removed through a water separator to promote the reaction equilibrium.
[0007] Furthermore, in step (1), the polyvinyl alcohol modified polyurethane emulsion includes the following components by mass: 90-100 parts of hydroxyl-terminated polydimethylsiloxane, 45-50 parts of diisocyanate, 3-5 parts of catalyst, 8-10 parts of hydrophilic chain extender, 90-100 parts of acetone, 350-400 parts of deionized water, 20-40 parts of polyvinyl alcohol, and 6-8 parts of triethylamine; The diisocyanate is one of diphenylmethane diisocyanate, isophorone diisocyanate, and hexamethylene diisocyanate; The catalyst is dibutyltin dilaurate; The hydrophilic chain extender is one of dimethylolpropionic acid or dimethylolbutyric acid. Furthermore, in step (2), the flame-retardant filler is prepared by the following process: adding dopamine hydrochloride and filler to Tris-HCl buffer solution, and then performing ultrasonic treatment, stirring reaction, vacuum filtration, washing and drying to obtain polydopamine-coated filler; adding polydopamine-coated filler and silane coupling agent KH-550 to ethanol aqueous solution, and then performing ultrasonic dispersion, stirring reaction, centrifugation, washing and drying to obtain flame-retardant filler.
[0008] Furthermore, the filler is one of aluminum hydroxide and magnesium hydroxide; The ratio of dopamine hydrochloride, filler, and Tris-HCl buffer is (2.2-2.6) g: (5-7) g: 1000 mL; The concentration of Tris-HCl buffer is 8-10 mmol / L, and the pH is 8.5.
[0009] Furthermore, the ratio of polydopamine-coated filler, silane coupling agent KH-550, and ethanol aqueous solution is (9-11)g:(0.4-0.6)mL:(200-300)mL; In an aqueous ethanol solution, the volume ratio of ethanol to water is (48-49):1.
[0010] Furthermore, in step (2), the mass ratio of polyvinyl alcohol modified polyurethane emulsion to flame retardant filler is 1:(0.1-0.3); The solid content of the impregnating material is 15-25%.
[0011] Furthermore, in step (3), the drying process conditions are: temperature 80-100℃, time 80-100min; The curing process conditions are: temperature 120-150℃, time 10-30min.
[0012] A halogen-free flame-retardant polyester nonwoven fabric for automotive interiors is prepared according to the above-mentioned preparation method.
[0013] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention introduces organosilicon segments into polyurethane prepolymers through the reaction of hydroxyl-terminated polydimethylsiloxane and diisocyanate. The introduction of organosilicon segments significantly improves the thermal stability and char-forming ability of polyurethane prepolymers, thereby enhancing their flame retardant properties.
[0014] 2. In this invention, the hydroxyl groups in polyvinyl alcohol react chemically with the isocyanate groups in polyurethane prepolymer, achieving chemical bonding between polyvinyl alcohol and polyurethane. This significantly enhances the interfacial adhesion and bonding strength between the coating and the polyester nonwoven fabric, preventing coating peeling. At the same time, the excellent film-forming properties and hydrophilicity of polyvinyl alcohol improve the storage stability of the emulsion and make the final coating more dense and uniform.
[0015] 3. This invention introduces DDP flame retardant into polyvinyl alcohol through an esterification reaction between the carboxyl group of DDP and the hydroxyl group of polyvinyl alcohol. When the DDP flame retardant burns, it releases phosphorus-containing free radicals, which can effectively capture free radicals in the gas phase and have excellent gas phase flame retardant effect. The introduction of DDP flame retardant significantly enhances the flame retardant performance of polyvinyl alcohol.
[0016] 4. This invention involves coating fillers such as aluminum hydroxide / magnesium hydroxide with polydopamine and surface-treating them with silane coupling agent KH-550. Polydopamine, with its abundant catechol and amino functional groups, can form a uniform and tough coating layer on the filler surface, greatly improving the surface polarity and interfacial activity of the filler. The silanol groups formed after the hydrolysis of silane coupling agent KH-550 can form covalent bonds with the polydopamine layer or the filler surface. The amino groups in coupling agent KH-550 form strong hydrogen bonds with the polar groups in the polyvinyl alcohol modified polyurethane matrix, and through their long molecular chains, they form physical entanglement and interpenetration with the polymer network, achieving highly uniform dispersion of the filler and effective stress transfer. Detailed Implementation
[0017] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0018] In the following specific implementation: The CAS number for hydroxyl-terminated polydimethylsiloxane is 70131-67-8, with a purity of 99%; the CAS number for diphenylmethane diisocyanate is 101-68-8, with a purity of 98%; the CAS number for isophorone diisocyanate is 4098-71-9, with a purity of 99%; the CAS number for hexamethylene diisocyanate is 822-06-0, with a purity of 99%; the CAS number for dibutyltin dilaurate is 77-58-7, with a purity of 99%; the CAS number for dimethylolpropionic acid is 4767-03-7, with a purity of 99%; the CAS number for dimethylolbutyric acid is 10097-02-6, with a purity of 99%; the CAS number for acetone is 67-64-1, with a purity of 99%; and the CAS number for polyvinyl alcohol is... The following are listed: CAS number 9002-89-5, purity 99%; CAS number 121-44-8, purity 99%; CAS number 63562-33-4, purity 98%; CAS number 104-15-4, purity 99%; CAS number 67-68-5, purity 99%; CAS number 104-15-4, purity 99%; CAS number 67-68-5, purity 99%; CAS number 1μm; CAS number 1μm; CAS number 62-31-7, purity 98%; CAS number 919-30-2, purity 99%; CAS number 64-17-5, purity 99%; CAS number 100g / m², purity of polyester nonwoven fabric. 2 .
[0019] Example 1: A method for preparing halogen-free flame-retardant polyester nonwoven fabric for automotive interiors, comprising the following steps: (1) Hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate and catalyst dibutyltin dilaurate are mixed and reacted. Then, hydrophilic chain extender dimethylolpropionic acid is added and the reaction is continued. After the reaction, acetone is added to prepare polyurethane prepolymer. Polyvinyl alcohol is added to a polyurethane prepolymer and reacted; triethylamine is added for neutralization, and the mixture is emulsified in deionized water under high-speed stirring to obtain a polyvinyl alcohol-modified polyurethane emulsion. The polyvinyl alcohol-modified polyurethane emulsion comprises the following components by mass: 95 parts hydroxyl-terminated polydimethylsiloxane, 48 parts isophorone diisocyanate, 4 parts dibutyltin dilaurate catalyst, 9 parts dimethylolpropionic acid hydrophilic chain extender, 95 parts acetone, 380 parts deionized water, 30 parts polyvinyl alcohol, and 7 parts triethylamine. (2) Polyvinyl alcohol modified polyurethane emulsion, flame retardant filler, and deionized water are mixed to obtain impregnating material; the mass ratio of polyvinyl alcohol modified polyurethane emulsion to flame retardant filler is 1:0.2; the solid content of impregnating material is 20%; (3) Immerse the polyester nonwoven fabric in the impregnating material for 20 minutes, take it out, dry it at 90°C for 90 minutes, and cure it at 140°C for 20 minutes to obtain halogen-free flame-retardant polyester nonwoven fabric. In step (1), polyvinyl alcohol undergoes flame retardant modification. The specific process is as follows: DDP, polyvinyl alcohol, and p-toluenesulfonic acid catalyst are added to dimethyl sulfoxide. After reaction, the mixture is precipitated, washed, and dried to obtain flame-retardant modified polyvinyl alcohol. The mass ratio of polyvinyl alcohol, DDP, and p-toluenesulfonic acid catalyst is 1:0.3:0.002; the ratio of polyvinyl alcohol to dimethyl sulfoxide is 1g:15mL; the reaction conditions are: under nitrogen protection, at a temperature of 115℃, for 8 hours. In step (2), the flame-retardant filler is prepared by the following process: Dopamine hydrochloride and aluminum hydroxide filler are added to Tris-HCl buffer solution, and after ultrasonic treatment, stirring reaction, vacuum filtration, washing and drying, polydopamine-coated aluminum hydroxide is obtained; polydopamine-coated aluminum hydroxide and silane coupling agent KH-550 are added to ethanol aqueous solution, and after ultrasonic dispersion, stirring reaction, centrifugation, washing and drying, flame-retardant filler is obtained; the ratio of dopamine hydrochloride, aluminum hydroxide filler and Tris-HCl buffer solution is 2.4g:6g:1000mL; the concentration of Tris-HCl buffer solution is 9mmol / L and the pH is 8.5; the ratio of polydopamine-coated aluminum hydroxide, silane coupling agent KH-550 and ethanol aqueous solution is 10g:0.5mL:250mL; in ethanol aqueous solution, the volume ratio of ethanol to water is 48.5:1.
[0020] Example 2: A method for preparing halogen-free flame-retardant polyester nonwoven fabric for automotive interiors, comprising the following steps: (1) Hydroxyl-terminated polydimethylsiloxane, diphenylmethane diisocyanate and catalyst dibutyltin dilaurate are mixed and reacted. Then, hydrophilic chain extender dimethylolpropionic acid is added and the reaction is continued. After the reaction, acetone is added to prepare polyurethane prepolymer. Polyvinyl alcohol was added to the polyurethane prepolymer and reacted; triethylamine was added for neutralization, and the mixture was emulsified in deionized water under high-speed stirring to obtain a polyvinyl alcohol-modified polyurethane emulsion. The polyvinyl alcohol-modified polyurethane emulsion comprises the following components by mass: 90 parts of hydroxyl-terminated polydimethylsiloxane, 45 parts of diphenylmethane diisocyanate, 3 parts of dibutyltin dilaurate catalyst, 8 parts of dimethylolpropionic acid hydrophilic chain extender, 90 parts of acetone, 350 parts of deionized water, 20 parts of polyvinyl alcohol, and 6 parts of triethylamine. (2) Polyvinyl alcohol modified polyurethane emulsion, flame retardant filler, and deionized water are mixed to obtain impregnating material; the mass ratio of polyvinyl alcohol modified polyurethane emulsion to flame retardant filler is 1:0.1; the solid content of impregnating material is 15%; (3) Immerse the polyester nonwoven fabric in the impregnating material for 15 minutes, take it out, dry it at 80°C for 100 minutes, and cure it at 120°C for 30 minutes to obtain halogen-free flame-retardant polyester nonwoven fabric. In step (1), polyvinyl alcohol undergoes flame retardant modification. The specific process is as follows: DDP, polyvinyl alcohol, and p-toluenesulfonic acid catalyst are added to dimethyl sulfoxide. After reaction, the mixture is precipitated, washed, and dried to obtain flame-retardant modified polyvinyl alcohol. The mass ratio of polyvinyl alcohol, DDP, and p-toluenesulfonic acid catalyst is 1:0.25:0.001. The ratio of polyvinyl alcohol to dimethyl sulfoxide is 1g:10mL. The reaction conditions are: under nitrogen protection, at a temperature of 110℃, the reaction is carried out for 10h. In step (2), the flame-retardant filler is prepared by the following process: Dopamine hydrochloride and magnesium hydroxide filler are added to Tris-HCl buffer solution, and after ultrasonic treatment, stirring reaction, vacuum filtration, washing and drying, polydopamine-coated magnesium hydroxide is obtained; polydopamine-coated magnesium hydroxide and silane coupling agent KH-550 are added to ethanol aqueous solution, and after ultrasonic dispersion, stirring reaction, centrifugation, washing and drying, flame-retardant filler is obtained; the ratio of dopamine hydrochloride, magnesium hydroxide filler and Tris-HCl buffer solution is 2.2g:5g:1000mL; the concentration of Tris-HCl buffer solution is 8mmol / L and the pH is 8.5; the ratio of polydopamine-coated magnesium hydroxide, silane coupling agent KH-550 and ethanol aqueous solution is 9g:0.4mL:200mL; in ethanol aqueous solution, the volume ratio of ethanol to water is 48:1.
[0021] Example 3: A method for preparing halogen-free flame-retardant polyester nonwoven fabric for automotive interiors, comprising the following steps: (1) Hydroxyl-terminated polydimethylsiloxane, hexamethylene diisocyanate and catalyst dibutyltin dilaurate are mixed and reacted. Then, hydrophilic chain extender dimethylolbutyric acid is added and the reaction is continued. After the reaction, acetone is added to prepare polyurethane prepolymer. Polyvinyl alcohol is added to a polyurethane prepolymer and reacted; triethylamine is added for neutralization, and the mixture is emulsified in deionized water under high-speed stirring to obtain a polyvinyl alcohol-modified polyurethane emulsion. The polyvinyl alcohol-modified polyurethane emulsion comprises the following components by mass: 100 parts of hydroxyl-terminated polydimethylsiloxane, 50 parts of hexamethylene diisocyanate, 5 parts of dibutyltin dilaurate catalyst, 10 parts of dimethylolbutyric acid hydrophilic chain extender, 100 parts of acetone, 400 parts of deionized water, 40 parts of polyvinyl alcohol, and 8 parts of triethylamine. (2) Polyvinyl alcohol modified polyurethane emulsion, flame retardant filler, and deionized water are mixed to obtain impregnating material; the mass ratio of polyvinyl alcohol modified polyurethane emulsion to flame retardant filler is 1:0.3; the solid content of impregnating material is 25%; (3) Immerse the polyester nonwoven fabric in the impregnating material for 30 minutes, take it out, dry it at 100°C for 80 minutes, and cure it at 150°C for 10 minutes to obtain halogen-free flame-retardant polyester nonwoven fabric. In step (1), polyvinyl alcohol undergoes flame retardant modification. The specific process is as follows: DDP, polyvinyl alcohol, and p-toluenesulfonic acid catalyst are added to dimethyl sulfoxide. After reaction, the mixture is precipitated, washed, and dried to obtain flame-retardant modified polyvinyl alcohol. The mass ratio of polyvinyl alcohol, DDP, and p-toluenesulfonic acid catalyst is 1:0.5:0.003; the ratio of polyvinyl alcohol to dimethyl sulfoxide is 1g:20mL; the reaction conditions are: under nitrogen protection, at a temperature of 120℃, for 6 hours. In step (2), the flame-retardant filler is prepared by the following process: Dopamine hydrochloride and aluminum hydroxide filler are added to Tris-HCl buffer solution, and after ultrasonic treatment, stirring reaction, vacuum filtration, washing and drying, polydopamine-coated aluminum hydroxide is obtained; polydopamine-coated aluminum hydroxide and silane coupling agent KH-550 are added to ethanol aqueous solution, and after ultrasonic dispersion, stirring reaction, centrifugation, washing and drying, flame-retardant filler is obtained; the ratio of dopamine hydrochloride, aluminum hydroxide filler and Tris-HCl buffer solution is 2.6g:7g:1000mL; the concentration of Tris-HCl buffer solution is 10mmol / L and the pH is 8.5; the ratio of polydopamine-coated aluminum hydroxide, silane coupling agent KH-550 and ethanol aqueous solution is 11g:0.6mL:300mL; in ethanol aqueous solution, the volume ratio of ethanol to water is 49:1.
[0022] Comparative Example 1: Based on Example 1, the polyvinyl alcohol was not modified with flame retardant, and the following steps were performed: (1) Hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate and catalyst dibutyltin dilaurate are mixed and reacted. Then, hydrophilic chain extender dimethylolpropionic acid is added and the reaction is continued. After the reaction, acetone is added to prepare polyurethane prepolymer. Polyvinyl alcohol is added to a polyurethane prepolymer and reacted; triethylamine is added for neutralization, and the mixture is emulsified in deionized water under high-speed stirring to obtain a polyvinyl alcohol-modified polyurethane emulsion. The polyvinyl alcohol-modified polyurethane emulsion comprises the following components by mass: 95 parts hydroxyl-terminated polydimethylsiloxane, 48 parts isophorone diisocyanate, 4 parts dibutyltin dilaurate catalyst, 9 parts dimethylolpropionic acid hydrophilic chain extender, 95 parts acetone, 380 parts deionized water, 30 parts polyvinyl alcohol, and 7 parts triethylamine. (2) Polyvinyl alcohol modified polyurethane emulsion, flame retardant filler, and deionized water are mixed to obtain impregnating material; the mass ratio of polyvinyl alcohol modified polyurethane emulsion to flame retardant filler is 1:0.2; the solid content of impregnating material is 20%; (3) Immerse the polyester nonwoven fabric in the impregnating material for 20 minutes, take it out, dry it at 90°C for 90 minutes, and cure it at 140°C for 20 minutes to obtain halogen-free flame-retardant polyester nonwoven fabric. In step (2), the flame-retardant filler is prepared by the following process: Dopamine hydrochloride and aluminum hydroxide filler are added to Tris-HCl buffer solution, and after ultrasonic treatment, stirring reaction, vacuum filtration, washing and drying, polydopamine-coated aluminum hydroxide is obtained; polydopamine-coated aluminum hydroxide and silane coupling agent KH-550 are added to ethanol aqueous solution, and after ultrasonic dispersion, stirring reaction, centrifugation, washing and drying, flame-retardant filler is obtained; the ratio of dopamine hydrochloride, aluminum hydroxide filler and Tris-HCl buffer solution is 2.4g:6g:1000mL; the concentration of Tris-HCl buffer solution is 9mmol / L and the pH is 8.5; the ratio of polydopamine-coated aluminum hydroxide, silane coupling agent KH-550 and ethanol aqueous solution is 10g:0.5mL:250mL; in ethanol aqueous solution, the volume ratio of ethanol to water is 48.5:1.
[0023] Comparative Example 2: Based on Example 1, the flame-retardant filler was replaced with an equal mass of aluminum hydroxide filler, including the following steps: (1) Hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate and catalyst dibutyltin dilaurate are mixed and reacted. Then, hydrophilic chain extender dimethylolpropionic acid is added and the reaction is continued. After the reaction, acetone is added to prepare polyurethane prepolymer. Polyvinyl alcohol is added to a polyurethane prepolymer and reacted; triethylamine is added for neutralization, and the mixture is emulsified in deionized water under high-speed stirring to obtain a polyvinyl alcohol-modified polyurethane emulsion. The polyvinyl alcohol-modified polyurethane emulsion comprises the following components by mass: 95 parts hydroxyl-terminated polydimethylsiloxane, 48 parts isophorone diisocyanate, 4 parts dibutyltin dilaurate catalyst, 9 parts dimethylolpropionic acid hydrophilic chain extender, 95 parts acetone, 380 parts deionized water, 30 parts polyvinyl alcohol, and 7 parts triethylamine. (2) Polyvinyl alcohol modified polyurethane emulsion, aluminum hydroxide filler, and deionized water are mixed to obtain impregnating material; the mass ratio of polyvinyl alcohol modified polyurethane emulsion to aluminum hydroxide filler is 1:0.2; the solid content of impregnating material is 20%; (3) Immerse the polyester nonwoven fabric in the impregnating material for 20 minutes, take it out, dry it at 90°C for 90 minutes, and cure it at 140°C for 20 minutes to obtain halogen-free flame-retardant polyester nonwoven fabric. In step (1), polyvinyl alcohol is modified with flame retardancy. The specific process is as follows: DDP, polyvinyl alcohol, and the catalyst p-toluenesulfonic acid are added to dimethyl sulfoxide. After reaction, the mixture is precipitated, washed, and dried to obtain polyvinyl alcohol modified with flame retardancy. The mass ratio of polyvinyl alcohol, DDP, and the catalyst p-toluenesulfonic acid is 1:0.3:0.002. The ratio of polyvinyl alcohol to dimethyl sulfoxide is 1g:15mL. The reaction conditions are: under nitrogen protection and at a temperature of 115℃, the reaction is carried out for 8 hours.
[0024] Comparative Example 3: Based on Example 1, the polyvinyl alcohol modified polyurethane emulsion was replaced with an equal mass of polyurethane, and the flame retardant filler was replaced with an equal mass of aluminum hydroxide filler, including the following steps: (1) Polyurethane, aluminum hydroxide filler and deionized water are mixed to obtain impregnating material; the mass ratio of polyurethane to aluminum hydroxide filler is 1:0.2; the solid content of impregnating material is 20%; (2) Immerse the polyester nonwoven fabric in the impregnating material for 20 minutes, take it out, dry it at 90°C for 90 minutes, and cure it at 140°C for 20 minutes to obtain halogen-free flame-retardant polyester nonwoven fabric.
[0025] Experiment: Halogen-free flame-retardant polyester nonwoven fabrics obtained in Examples 1-3 and Comparative Examples 1-3 were used to prepare samples. Their properties were tested, and the results were recorded. Horizontal burning rate: Referencing GB8410-2006 "Combustion characteristics of automotive interior materials", the horizontal burning rate of halogen-free flame-retardant polyester nonwoven fabric was tested; Vertical burning rate test: Refer to GB / T 32086-2015 "Technical requirements and test methods for vertical burning characteristics of specific types of automotive interior materials" to test the vertical burning rate of halogen-free flame-retardant polyester nonwoven fabric; Limiting oxygen index test: Refer to GB / T 5454-1997 "Test for flammability of textiles - Oxygen index method" to test the limiting oxygen index of halogen-free flame-retardant polyester nonwoven fabric.
[0026]
[0027] Conclusion: As can be seen from the comparison of data in Table 1, the performance of the halogen-free flame-retardant polyester nonwoven fabrics prepared in Comparative Examples 1-3 is significantly reduced compared to those prepared in Examples 1-3. Comparative Example 1: Based on Example 1, the performance of the halogen-free flame-retardant polyester nonwoven fabric prepared without flame-retardant modification of polyvinyl alcohol was significantly reduced. This indicates that DDP flame-retardant modification of polyvinyl alcohol is an important step in improving the flame-retardant efficiency of the system. By introducing phosphorus-based flame-retardant structures into the polymer matrix through chemical grafting, the synergistic flame-retardant effect of the gas phase and condensed phase can be effectively exerted.
[0028] Comparative Example 2: Based on Example 1, the flame retardant filler was replaced with an equal mass of aluminum hydroxide filler. The performance of the resulting halogen-free flame retardant polyester nonwoven fabric was significantly reduced, indicating that the unmodified aluminum hydroxide filler has poor dispersibility and is prone to agglomeration in the resin, resulting in a decrease in flame retardant performance.
[0029] Comparative Example 3: Based on Example 1, the polyvinyl alcohol modified polyurethane emulsion was replaced with an equal mass of polyurethane, and the flame retardant filler was replaced with an equal mass of aluminum hydroxide filler. The performance of the resulting halogen-free flame retardant polyester nonwoven fabric was significantly reduced, which confirms the importance of the preparation process of the polyvinyl alcohol modified polyurethane emulsion and the surface modified flame retardant filler of the present invention.
[0030] In summary, this invention significantly improves the flame retardant properties of polyester nonwoven fabrics by employing multiple modification strategies, including DDP flame-retardant modified polyvinyl alcohol, silicone / polyvinyl alcohol composite modified polyurethane, and surface treatment of flame-retardant fillers. It also inhibits the spread of combustion and overcomes the problems of easy embrittlement and short-lasting flame retardant effect of traditional halogen-free flame retardant systems. This invention has obvious technical advantages and application value.
[0031] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.
Claims
1. A method for preparing halogen-free flame-retardant polyester nonwoven fabric for automotive interiors, characterized in that: Includes the following steps: (1) Hydroxyl-terminated polydimethylsiloxane, diisocyanate and catalyst are mixed and reacted. A hydrophilic chain extender is added and the reaction continues. After the reaction, acetone is added to prepare polyurethane prepolymer. Polyvinyl alcohol was added to the polyurethane prepolymer and reacted; triethylamine was added to neutralize it, and the mixture was poured into deionized water under high-speed stirring to emulsify, thus obtaining a polyvinyl alcohol-modified polyurethane emulsion. (2) Mix polyvinyl alcohol modified polyurethane emulsion, flame retardant filler and deionized water to obtain impregnation material; (3) Immerse the polyester nonwoven fabric in the impregnating material for 15-30 minutes, take it out, and then dry and cure it to obtain halogen-free flame-retardant polyester nonwoven fabric.
2. The method for preparing a halogen-free flame-retardant polyester nonwoven fabric for automotive interiors according to claim 1, characterized in that: In step (1), the polyvinyl alcohol is modified with flame retardant. The specific process is as follows: [(6-oxo-6H-dibenzo[c,e][1,2]oxophosphoric acid-6-yl)methyl]succinic acid, polyvinyl alcohol, and the catalyst p-toluenesulfonic acid are added to dimethyl sulfoxide. After the reaction, the mixture is precipitated, washed, and dried to obtain polyvinyl alcohol modified with flame retardant.
3. The method for preparing a halogen-free flame-retardant polyester nonwoven fabric for automotive interiors according to claim 2, characterized in that: The mass ratio of polyvinyl alcohol, [(6-oxo-6H-dibenzo[c,e][1,2]oxophosphorylhexane-6-yl)methyl]succinic acid, and the catalyst p-toluenesulfonic acid is 1:(0.25-0.5):(0.001-0.003).
4. The method for preparing a halogen-free flame-retardant polyester nonwoven fabric for automotive interiors according to claim 2, characterized in that: The ratio of polyvinyl alcohol to dimethyl sulfoxide is 1g:(10-20)mL.
5. The method for preparing a halogen-free flame-retardant polyester nonwoven fabric for automotive interiors according to claim 1, characterized in that: In step (1), the polyvinyl alcohol modified polyurethane emulsion comprises the following components by mass: 90-100 parts of hydroxyl-terminated polydimethylsiloxane, 45-50 parts of diisocyanate, 3-5 parts of catalyst, 8-10 parts of hydrophilic chain extender, 90-100 parts of acetone, 350-400 parts of deionized water, 20-40 parts of polyvinyl alcohol, and 6-8 parts of triethylamine.
6. The method for preparing a halogen-free flame-retardant polyester nonwoven fabric for automotive interiors according to claim 1, characterized in that: In step (2), the flame-retardant filler is prepared by the following process: adding dopamine hydrochloride and filler to Tris-HCl buffer solution, and then performing ultrasonic treatment, stirring reaction, vacuum filtration, washing and drying to obtain polydopamine-coated filler; adding polydopamine-coated filler and silane coupling agent KH-550 to ethanol aqueous solution, and then performing ultrasonic dispersion, stirring reaction, centrifugation, washing and drying to obtain flame-retardant filler.
7. The method for preparing a halogen-free flame-retardant polyester nonwoven fabric for automotive interiors according to claim 1, characterized in that: In step (2), the mass ratio of the polyvinyl alcohol modified polyurethane emulsion to the flame retardant filler is 1:(0.1-0.3).
8. The method for preparing a halogen-free flame-retardant polyester nonwoven fabric for automotive interiors according to claim 1, characterized in that: In step (2), the solid content of the impregnating material is 15-25%.
9. The method for preparing a halogen-free flame-retardant polyester nonwoven fabric for automotive interiors according to claim 1, characterized in that: In step (3), the drying process conditions are: temperature 80-100℃, time 80-100min; the curing process conditions are: temperature 120-150℃, time 10-30min.
10. A halogen-free flame-retardant polyester nonwoven fabric for automotive interiors, characterized in that: Prepared by the preparation method according to any one of claims 1-9.