Modified bio-based fireproof intumescent flame retardant coating, open self-rolling fireproof braided tube and preparation method thereof, wire harness fireproof assembly

Abstract

This disclosure provides a modified bio-based fire-retardant intumescent flame-retardant coating, an open self-winding fire-retardant braided tube, a method for preparing the same, and a fire-retardant wire harness assembly. The modified bio-based fire-retardant intumescent flame-retardant coating comprises: 30-40 parts of bio-based phosphorus-containing polyol; 5-10 parts of isoflurane isocyanate; 20-25 parts of non-polyphosphate ammonium intumescent flame retardant; 8-20 parts of synergist; 0.03-0.2 parts of catalyst; and 1-5 parts of chain extender; wherein the bio-based phosphorus-containing polyol is composed of bio-based polyol and phosphorus-containing polyol. This coating, through the synergistic effect of the polar-nonpolar dual structure of bio-based phosphorus-containing polyols and non-polyphosphate ammonium intumescent flame retardants, achieves uniform spreading of modified bio-based fire-retardant coatings on the surfaces of different polar fibers. This facilitates the formation of ultra-thin, highly flexible, dense modified bio-based fire-retardant coatings free from pinholes, craters, and missed areas, with strong adhesion and high water resistance, thus meeting the fire safety requirements of extreme fire conditions and humid environments.

Description

Technical Field

[0001] This disclosure relates to the field of fire-retardant and flame-inflating coating technology, and in particular to a modified bio-based fire-retardant and flame-inflating coating, an open self-winding fire-retardant braided tube and its preparation method, and a fire-retardant wire harness assembly. Background Technology

[0002] With the rapid development of transportation industries such as new energy vehicles and subways, the safety protection requirements for important cable harnesses such as high-voltage wire harnesses and traction wire harnesses are becoming increasingly stringent. Existing modified bio-based fire-retardant coatings mostly use PET and PP filaments as the woven self-winding layer, that is, they are woven from two types of fiber monofilaments with significantly different polarities, supplemented by an organic fire-retardant coating. Organic fire-retardant coatings include petroleum-based organic fire-retardant coatings and bio-based organic fire-retardant coatings. Because bio-based fire-retardant coatings have high flexibility, low carbon footprint, and strong interfacial adhesion to PET and PP substrates, they can compensate for the shortcomings of petroleum-based organic coatings, making them particularly suitable for the application of modified bio-based fire-retardant coatings.

[0003] For example, the bio-based fire-retardant coating disclosed in patent TWI879538B uses bio-based chitosan as the main material. However, because the non-polar short carbon chains of bio-based chitosan are wrapped with polar groups, the bio-based chitosan has extremely high polarity. It cannot be evenly spread on low-polarity PP fiber monofilaments, and is prone to pinholes and missed coatings, thus failing to provide good fireproof and heat insulation. Furthermore, due to the high rigidity and brittleness of bio-based chitosan, traditional bio-based fire-retardant coatings have poor flexibility and are prone to peeling, making them unsuitable for the fire safety requirements of enclosed spaces such as high-pressure chambers of new energy vehicles and subway traction systems in extreme fire scenarios. Summary of the Invention

[0004] The purpose of this disclosure is to overcome the shortcomings of the prior art and provide a modified bio-based fire-retardant coating that achieves uniform spreading on the surface of different polar fibers through the synergistic effect of the polar-nonpolar dual structure of bio-based phosphorus-containing polyols and non-polyphosphate ammonium intumescent flame retardants. This facilitates the formation of ultra-thin, highly flexible, dense modified bio-based fire-retardant coatings free from shrinkage cavities, pinholes, and missed coatings, with strong connectivity and high water resistance. It ensures that the formed ultra-thin modified bio-based fire-retardant coating does not damage the self-rolling elasticity and flexibility of the braided self-rolling layer, and can guarantee the formation of an effective fire-retardant and heat-insulating layer after exposure to fire. This is to meet the fire safety requirements of extreme fire conditions and humid environments. The disclosure also includes a modified bio-based fire-retardant coating, an open self-rolling fire-retardant braided tube, its preparation method, and a wire harness fire-retardant component.

[0005] The purpose of this disclosure is achieved through the following technical solution: A modified bio-based fire-retardant and intumescent flame-retardant coating is disposed on at least one side of a woven self-winding layer, wherein the woven self-winding layer is woven from two types of fiber monofilaments with significantly different polarities, and the modified bio-based fire-retardant and intumescent flame-retardant coating comprises the following parts by weight: 30-40 parts of bio-based phosphorus-containing polyols; 5-10 parts of isoflurane isocyanate; 20-25 parts of non-polyphosphate ammonium intumescent flame retardant; Synergistic agent 8-20 parts; Catalyst: 0.03-0.2 parts; Chain extender 1-5 parts; The bio-based phosphorus-containing polyol is composed of bio-based polyol and phosphorus-containing polyol.

[0006] In one embodiment, the bio-based polyol includes at least one of castor oil, dimer diol, soybean oil polyol.

[0007] In one embodiment, the phosphorus-containing polyol includes at least one of organophosphate diol, tris(dipropylene glycol) phosphite, diethyl N,N-di(2-hydroxyethyl)aminomethylenephosphonate and dimethyl N,N-di(2-hydroxyethyl)aminomethylenephosphonate.

[0008] In one embodiment, the bio-based phosphorus-containing polyol is obtained by mixing a bio-based polyol with a phosphorus-containing polyol at a mass ratio of 100:(5~20).

[0009] In one embodiment, the synergist includes at least one of nano-montmorillonite, carbon black, and silane coupling agents.

[0010] In one embodiment, the non-polyphosphate intumescent flame retardant comprises at least one of melamine bicyclic cage phosphate, monocage phosphate melamine salt and tricage phosphate melamine salt, piperazine pyrophosphate, and pentaerythritol diphosphate salt; and / or, The modified bio-based fire-retardant and intumescent coating has a thickness of 0.1 mm to 0.5 mm; and / or, The woven self-winding layer is woven from PET and PP yarns.

[0011] An open-end self-winding fireproof braided tube includes a braided self-winding layer and the modified bio-based fire-retardant and intumescent flame-retardant coating described in any of the above embodiments.

[0012] A method for preparing an open-end self-winding fireproof braided tubing includes the following steps: Obtain the modified bio-based fire-retardant and intumescent flame-retardant coating as described in any of the above embodiments; The modified bio-based fire-retardant and flame-inflating coating is applied to one side of the braided self-winding layer to obtain a self-winding fireproof braided tube precursor. The self-winding fireproof braided tube precursor is cured and then shaped to obtain the open self-winding fireproof braided tube.

[0013] In one embodiment, the step of obtaining the modified bio-based fire-retardant and intumescent flame-retardant coating further includes the following steps: adding a moderately polar organic solvent to adjust the viscosity of the modified bio-based fire-retardant and intumescent flame-retardant coating to 200 mPa·s-500 mPa·s; and / or, The curing conditions are: temperature 60℃-80℃; time 1h-2h.

[0014] A fire-resistant wire harness assembly includes the open self-winding fire-resistant braided tubing described in any of the above embodiments.

[0015] Compared with the prior art, this disclosure has at least the following advantages: Because bio-based phosphorus-containing polyols are composed of bio-based polyols and phosphorus-containing polyols, the linear long-chain aliphatic hydrocarbons of the bio-based polyols are not easily encapsulated by the polar groups (phospho-oxygen bonds, hydroxyl groups) of the phosphorus-containing polyols, thus exposing the long-chain aliphatic hydrocarbons. This ensures that the bio-based phosphorus-containing polyols possess both polar and non-polar dual structures, effectively eliminating surface tension with the non-polar fibers (PP monofilaments) in the fiber gaps. This ensures that the bio-based phosphorus-containing polyols can spread evenly on the surfaces of the two different polarities of fibers, avoiding the formation of phosphorus-containing polyols in the fiber gaps. Addressing the issues of pinholes and missed coatings, this method effectively reduces the probability of pinholes and missed coatings in modified bio-based fire-retardant intumescent coatings. Especially when used in conjunction with isoflurane isocyanate, non-polyphosphate ammonium intumescent flame retardants, chain extenders, and synergists, it ensures that a smaller amount of the modified bio-based fire-retardant intumescent coating meets flame retardant performance requirements. This allows the bio-based phosphorus-containing polyols and isoflurane isocyanate to crosslink and form a highly flexible, dense, pinhole-free, and well-connected modified bio-based fire-retardant intumescent coating, free from pinholes, missed coatings, and other defects. This ensures the formation of an ultra-thin modified bio-based fire-retardant intumescent coating. The flame-retardant coating does not compromise the self-rolling elasticity and flexibility of the woven self-rolling layer, while ensuring the formation of an effective fire-resistant, expanding, and heat-insulating layer upon exposure to fire, thus guaranteeing flame-retardant performance. Due to the high flexibility of the linear long-chain aliphatic hydrocarbons in bio-based polyols, the prepared modified bio-based fire-resistant, expanding, and flame-retardant coating exhibits an elongation at break ≥300%, and shows no brittleness or delamination under cycling conditions from -40℃ to 150℃, effectively solving the problem of poor flexibility and easy detachment in traditional bio-based fire-retardant coatings. Furthermore, bio-based phosphorus-containing polyols can catalyze the formation of a continuous and dense modified bio-based polyol at high temperatures. The bio-based fire-retardant and intumescent flame-retardant coating has a higher char formation efficiency and better char layer flexibility than bio-based chitosan, effectively reducing the probability of the modified bio-based fire-retardant and intumescent flame-retardant coating peeling off in extreme fire scenarios. Furthermore, since the bio-based phosphorus-containing polyol itself contains phosphorus, it can form a phosphorus-nitrogen synergistic flame retardant with non-polyphosphate ammonium intumescent flame retardants under high temperature conditions, which not only improves the flame retardant efficiency but also reduces the total amount of non-polyphosphate ammonium intumescent flame retardants added, so as to better adapt to the fire safety level requirements of enclosed spaces such as high-pressure chambers of new energy vehicles and subway traction systems in extreme fire scenarios.

[0016] Although the added bio-based phosphorus-containing polyol can effectively eliminate the surface tension of the non-polar fibers (PP monofilaments) between the fibers to a certain extent, it weakens the bonding force between the bio-based phosphorus-containing polyol and the high-polarity fiber (PET monofilaments). Therefore, in this disclosure, by adding a non-polyphosphate ammonium intumescent flame retardant, the polar groups of the added non-polyphosphate ammonium intumescent flame retardant can better supplement the polarity of the bio-based phosphorus-containing polyol, thereby enhancing the bonding force between the modified bio-based fire-retardant intumescent flame retardant coating and the high-polarity fiber monofilaments. This ensures that a modified bio-based fire-retardant intumescent flame retardant coating with high bonding strength is obtained after final curing. It also avoids the problem of performance degradation of the modified bio-based fire-retardant intumescent flame retardant coating due to the agglomeration of bio-based phosphorus-containing polyol, ensuring that the modified bio-based fire-retardant intumescent flame retardant coating has the characteristics of high flexibility and high fire resistance. In addition, due to the low moisture absorption and high compatibility of non-polyphosphate ammonium intumescent flame retardant, it not only improves the water resistance of modified bio-based fire-retardant intumescent flame retardant coatings, ensuring that the modified bio-based fire-retardant intumescent flame retardant coatings do not become damp or precipitate during long-term storage, but also maintain stable performance in humid environments, so as to better meet the fire safety requirements of enclosed spaces such as high-pressure chambers of new energy vehicles and subway traction systems in humid environments and extreme fire scenarios.

[0017] By combining bio-based phosphorus-containing polyols, isoflurane isocyanates, non-polyphosphate ammonium intumescent flame retardants, synergists, catalysts, and chain extenders, a dual mechanism of intrinsic flame retardancy and intumescent flame retardancy is achieved in the modified bio-based fire-retardant intumescent flame-retardant coating. The synergistic effect of added synergists, such as silane coupling agents, carbon black, and nano-montmorillonite, facilitates the formation of a ceramicized char layer, solving the problems of easy peeling and insufficient char layer strength in traditional intumescent coatings. This ensures the stability of the modified bio-based fire-retardant intumescent flame-retardant coating under long-term bending, vibration, and high / low temperature cycling environments. It also achieves rapid expansion within 30 seconds of exposure to fire, resulting in a dense, non-collapsed char layer with significant heat insulation, ensuring the normal operation of the wiring harness in a short time and effectively preventing the spread of fire on the wiring harness. Furthermore, it solves the problems of high-temperature dripping defects and insufficient expansion flexibility in traditional polyurethane coatings, thereby broadening the selection range of fire-retardant substrate resins. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this disclosure and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the unfolding structure of an open self-winding fireproof braided tube according to an embodiment of the present invention; Figure 2This is a schematic diagram of the structure of an open self-winding fireproof braided tube according to an embodiment of the present invention from another direction; Figure 3 This is a cross-sectional view of an open self-winding fireproof braided tube according to an embodiment of the present invention; Figure 4 for Figure 3 The enlarged view at point A is shown below; Figure 5 This is a physical diagram of a wire harness fireproof assembly according to an embodiment of the present invention.

[0020] Reference numerals: 10, Open self-winding fireproof braided tubing; 100, Braided self-winding layer; 110, Opening overlap area; 120, Self-winding cavity; 130, Inner winding surface; 140, Outer winding surface; 150, Winding start end; 160, Winding end end; 200, Modified bio-based fire-retardant and flame-inflating coating; 300, Modified bio-based fire-retardant and flame-inflating sub-coating; 20, Wire harness. Detailed Implementation

[0021] To facilitate understanding of this disclosure, a more complete description will be given below with reference to the accompanying drawings, which illustrate preferred embodiments of the present disclosure. However, this disclosure can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure.

[0022] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this disclosure. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0024] To better understand the technical solutions and beneficial effects of this disclosure, the following detailed description is provided in conjunction with specific embodiments: An embodiment of a modified bio-based fire-retardant and intumescent flame-retardant coating is disposed on at least one side of a woven self-rolling layer. The modified bio-based fire-retardant and intumescent flame-retardant coating comprises the following parts by weight: 30-40 parts of bio-based phosphorus-containing polyol; 5-10 parts of isoflurane isocyanate; 20-25 parts of non-polyphosphate ammonium intumescent flame retardant; 8-20 parts of synergist; 0.03-0.2 parts of catalyst; and 1-5 parts of chain extender; wherein the bio-based phosphorus-containing polyol is composed of bio-based polyol and phosphorus-containing polyol.

[0025] Understandably, since bio-based phosphorus-containing polyols are composed of bio-based polyols and phosphorus-containing polyols, ensuring that the linear long-chain aliphatic hydrocarbons of the bio-based polyols are not easily encapsulated by the polar groups (phospho-oxygen bonds, hydroxyl groups) of the phosphorus-containing polyols exposes the long-chain aliphatic hydrocarbons. This ensures that the bio-based phosphorus-containing polyols possess both polar and non-polar dual structures, effectively eliminating surface tension with the non-polar fibers (PP monofilaments) in the fiber gaps. This ensures that the bio-based phosphorus-containing polyols can spread evenly on the surfaces of the two different polarities of fibers, preventing the bio-based phosphorus-containing polyols from appearing in the fiber gaps. Addressing the issues of pinholes or missed coatings, this method effectively reduces the probability of pinholes and missed coatings in modified bio-based fire-retardant intumescent flame-retardant coatings. Especially when used in conjunction with isoflurane isocyanate, non-polyphosphate ammonium intumescent flame retardants, chain extenders, and synergists, it ensures that a smaller amount of the modified bio-based fire-retardant intumescent flame-retardant coating meets flame-retardant performance requirements. This allows the bio-based phosphorus-containing polyols and isoflurane isocyanate to crosslink and form a highly flexible, dense, pinhole-free, and well-connected modified bio-based fire-retardant intumescent flame-retardant coating 200, thus ensuring the formation of an ultra-thin modified bio-based fire-retardant intumescent flame-retardant coating. Coating 200 does not compromise the self-rolling elasticity and flexibility of the woven self-rolling layer, while ensuring the formation of an effective fire-resistant, expanding, and heat-insulating layer upon exposure to fire, thus guaranteeing flame-retardant performance. Due to the high flexibility of the linear long-chain aliphatic hydrocarbons in bio-based polyols, the prepared modified bio-based fire-resistant, expanding, and flame-retardant coating 200 exhibits an elongation at break ≥300%, and shows no brittleness or delamination under cycling conditions from -40℃ to 150℃, effectively solving the problem of poor flexibility and easy detachment in traditional bio-based fire-retardant coatings. Furthermore, bio-based phosphorus-containing polyols can catalyze the formation of continuous, dense modified bio-based polyols at high temperatures. The modified bio-based fire-retardant intumescent flame-retardant coating 200 has a higher char formation efficiency and better char layer flexibility than bio-based chitosan, effectively reducing the probability of peeling off the modified bio-based fire-retardant intumescent flame-retardant coating 200 in extreme fire scenarios. Furthermore, since the bio-based phosphorus-containing polyol itself contains phosphorus source, it can form phosphorus and nitrogen synergistic flame retardancy with non-polyphosphate ammonium intumescent flame retardants under high temperature conditions, which not only improves the flame retardant efficiency but also reduces the total amount of non-polyphosphate ammonium intumescent flame retardants added, so as to better adapt to the fire safety level requirements of enclosed spaces such as high-pressure chambers of new energy vehicles and subway traction systems in extreme fire scenarios.

[0026] It is also understandable that although the added bio-based phosphorus-containing polyol can effectively eliminate the surface tension of the non-polar fibers (PP monofilaments) between the fibers to a certain extent, it will weaken the bonding force between the bio-based phosphorus-containing polyol and the high-polarity fiber monofilaments. Therefore, in this disclosure, by adding a non-polyphosphate ammonium intumescent flame retardant, the polar groups of the added non-polyphosphate ammonium intumescent flame retardant can better supplement the polarity of the bio-based phosphorus-containing polyol, thereby enhancing the bonding force between the modified bio-based fire-retardant intumescent flame retardant coating and the high-polarity fiber monofilaments. This ensures that a modified bio-based fire-retardant intumescent flame retardant coating 200 with high bonding strength is obtained after final curing. It also avoids the problem of the bio-based phosphorus-containing polyol agglomerating, which would lead to a decrease in the performance of the modified bio-based fire-retardant intumescent flame retardant coating. This ensures that the modified bio-based fire-retardant intumescent flame retardant coating 200 has the characteristics of high flexibility and high fire resistance. In addition, due to the low moisture absorption and high compatibility of non-polyphosphate ammonium intumescent flame retardant, it not only improves the water resistance of modified bio-based fire-retardant intumescent flame retardant coatings, ensuring that the modified bio-based fire-retardant intumescent flame retardant coatings do not become damp or precipitate during long-term storage, but also maintain stable performance in humid environments, so as to better meet the fire safety requirements of enclosed spaces such as high-pressure chambers of new energy vehicles and subway traction systems in humid environments and extreme fire scenarios.

[0027] It can also be understood that by using bio-based phosphorus-containing polyols, isoflurane isocyanates, non-polyphosphate ammonium intumescent flame retardants, synergists, catalysts, and chain extenders in combination, the modified bio-based fire-retardant intumescent flame retardant coating achieves both intrinsic flame retardancy and intumescent flame retardancy. The synergistic effect of added synergists, such as silane coupling agents, carbon black, and nano-montmorillonite, facilitates the formation of a ceramicized char layer, solving the problems of easy peeling and insufficient char layer strength in traditional intumescent coatings. This ensures the stability of the modified bio-based fire-retardant intumescent flame retardant coating 200 under long-term bending, vibration, and high / low temperature cycling environments. It also achieves rapid expansion within 30 seconds of exposure to fire, resulting in a dense, non-collapsed char layer with significant heat insulation, ensuring the normal operation of the wire harness 20 in a short time and effectively preventing the spread of fire on the wire harness 20. Furthermore, it solves the problems of high-temperature dripping defects and insufficient expansion flexibility in traditional polyurethane coatings, thereby broadening the range of fire-retardant substrate resins.

[0028] In one embodiment, the bio-based polyol includes at least one of castor oil, dimer diol, and soybean oil polyol to ensure that the bio-based polyol contains linear long-chain aliphatic hydrocarbons, thereby ensuring that the linear long-chain aliphatic hydrocarbons of the bio-based polyol are not easily encapsulated by the polar groups (phosphorus oxygen bonds, hydroxyl groups) of the phosphorus-containing polyol.

[0029] In one embodiment, the castor oil has a functionality of 2-3, a hydroxyl value of 35mgKOH / g-80mgKOH / g, and a molecular weight of 1000-3000 to ensure that the bio-based polyol contains linear long-chain aliphatic hydrocarbons, thus ensuring that the linear long-chain aliphatic hydrocarbons of the bio-based polyol are not easily encapsulated by the polar groups (phosphorus oxygen bonds, hydroxyl groups) of the phosphorus-containing polyol.

[0030] In one embodiment, the castor oil has a functionality of 2.2, a hydroxyl value of 52 mg KOH / g, and a molecular weight of 2610, to ensure that the bio-based polyol contains linear long-chain aliphatic hydrocarbons, thus ensuring that the linear long-chain aliphatic hydrocarbons of the bio-based polyol are not easily encapsulated by the polar groups (phosphorus oxygen bonds, hydroxyl groups) of the phosphorus-containing polyol.

[0031] In one embodiment, the linear long-chain aliphatic hydrocarbon of the dimer diol has 28-54 carbon atoms; a hydroxyl value of 185 mg KOH / g-210 mg KOH / g; and a molecular weight of 424-792.

[0032] In one embodiment, the linear long-chain aliphatic hydrocarbon of the dimer diol has 36 carbon atoms, a functionality of 2, a relative density of 0.90, and a molecular weight of 536.

[0033] In one embodiment, the soybean oil polyol has a functionality of 2.0, a hydroxyl value of 56 mg KOH / g, and a molecular weight of 1700.

[0034] In one embodiment, the bio-based polyol is a mixture of castor oil, dimer diol, and soybean oil polyol.

[0035] In one embodiment, when the bio-based polyol is a mixture of castor oil, dimer diol and soybean oil polyol, the mass ratio of the mixture of castor oil, dimer diol and soybean oil polyol is (40-50):(20-40):(10-20).

[0036] In one embodiment, the phosphorus-containing polyol includes at least one of organophosphate diol, tris(dipropylene glycol) phosphite, diethyl N,N-di(2-hydroxyethyl)aminomethylenephosphonate and dimethyl N,N-di(2-hydroxyethyl)aminomethylenephosphonate.

[0037] In one embodiment, the phosphorus content of the organophosphate diol is 16%-18.0%.

[0038] In one embodiment, the phosphorus content of tris(dipropylene glycol) phosphite is 7.0%-8.0%.

[0039] In one embodiment, the phosphorus content of N,N-bis(2-hydroxyethyl)aminomethylenephosphonate diethyl ester is 10.0%-15.0%, and the nitrogen content is 5.0%-6.0%.

[0040] In one embodiment, the phosphorus content of N,N-bis(2-hydroxyethyl)aminomethylenephosphonate dimethyl ester is 13.0%-15.0%, and the nitrogen content is 5.0%-6.0%, to ensure that the added phosphorus content is appropriate, effectively avoiding the problem of easy agglomeration and cracking of the modified bio-based fire-retardant coating due to excessive phosphorus content, and also effectively avoiding the problem of flame retardant failure due to excessively low phosphorus content.

[0041] In one embodiment, the bio-based phosphorus-containing polyol is obtained by mixing bio-based polyol and phosphorus-containing polyol at a mass ratio of 100:(5~20) to ensure that the mass ratio of bio-based polyol and phosphorus-containing polyol is suitable. In particular, with the use of 20-25 parts of non-polyphosphate ammonium intumescent flame retardant, it is ensured that the linear long-chain aliphatic hydrocarbons of the bio-based polyol are not easily wrapped by the polar groups (phosphorus oxygen bond, hydroxyl group) of the phosphorus-containing polyol, thereby ensuring that the bio-based phosphorus-containing polyol has both polar and non-polar dual structures.

[0042] In one embodiment, the non-polyphosphate intumescent flame retardant includes at least one of melamine bicyclic cage phosphate, monocage phosphate melamine salt and tricage phosphate melamine salt, piperazine pyrophosphate, and pentaerythritol diphosphate salt.

[0043] It is understandable that melamine bicyclic cage phosphate, monocage phosphate melamine salt, tricage phosphate melamine salt, piperazine pyrophosphate, and pentaerythritol diphosphate salt all contain P=O, -NH2 / -NH-, POC, and surface polar sites (Si-OH and quaternary ammonium cations) of organic modified layered silicates. The polar groups of quaternary ammonium cations can better complement the polarity of bio-based phosphorus-containing polyols, thereby enhancing the bonding force between the modified bio-based fire-retardant and intumescent flame-retardant coating and the high-polarity fiber monofilament, and ensuring the connection strength between the modified bio-based fire-retardant and intumescent flame-retardant coating 200 and the woven self-winding layer. Meanwhile, the added melamine bicyclic cage phosphate, monocage phosphate melamine salt and tricage phosphate melamine salt, piperazine pyrophosphate, and pentaerythritol diphosphate salt can improve the fireproof and flame-retardant properties of the modified bio-based fire-retardant intumescent coating 200. In this way, it is ensured that the added non-polyphosphate ammonium intumescent flame retardant not only improves the fireproof and flame-retardant properties of the modified bio-based fire-retardant intumescent coating 200, but also improves the connection strength between the modified bio-based fire-retardant intumescent coating 200 and the woven self-winding layer.

[0044] Specifically, the P=O groups of melamine bicyclic cage phosphate, monocage phosphate melamine salt, tricage phosphate melamine salt, piperazine pyrophosphate, and pentaerythritol diphosphate salt form hydrogen bonds with the -OH groups of bio-based phosphorus-containing polyols, anchoring them within the polyurethane network cross-linked and cured by bio-based phosphorus-containing polyols and isoflurane isocyanate, effectively avoiding the migration problem of non-polyphosphate ammonium intumescent flame retardants; -NH2 / -NH- can weakly interact with the NCO groups of isoflurane isocyanate, improving the dispersibility of melamine bicyclic cage phosphate in the matrix; and at high temperatures, the polar groups of melamine bicyclic cage phosphate, monocage phosphate melamine salt, tricage phosphate melamine salt, piperazine pyrophosphate, and pentaerythritol diphosphate salt break, releasing polyphosphoric acid (acid source) and NH3 (gas source), catalyzing char formation, and improving the fireproof and flame-retardant performance of the modified bio-based fire-retardant intumescent flame retardant coating 200.

[0045] In one embodiment, the melamine bicyclic cage phosphate is at least one of Melabis329 and Charguard329.

[0046] In one embodiment, the synergist includes at least one of nano-montmorillonite, carbon black, and silane coupling agents.

[0047] In one embodiment, the synergist includes nano-montmorillonite, carbon black, and a silane coupling agent.

[0048] In one embodiment, the amount of nano-montmorillonite used is 5-15 parts by weight; the amount of carbon black used is 1-5 parts; and the amount of silane coupling agent used is 0.5-1 part.

[0049] In one embodiment, the silane coupling agent is designated KH-590.

[0050] It should be noted that if the thickness of the modified bio-based fire-retardant and intumescent flame-retardant coating is too thick, it will affect the self-rolling elasticity and flexibility of the braided self-rolling layer. If the thickness of the modified bio-based fire-retardant and intumescent flame-retardant coating is too thin, it cannot guarantee the formation of an effective fire-retardant and intumescent heat-insulating layer after exposure to fire. In one embodiment, the thickness of the modified bio-based fire-retardant and intumescent flame-retardant coating is 0.1mm-0.5mm to ensure that the thickness of the modified bio-based fire-retardant and intumescent flame-retardant coating is relatively thin. This ensures that the added modified bio-based fire-retardant and intumescent flame-retardant coating does not damage the self-rolling elasticity and flexibility of the braided self-rolling layer, while guaranteeing that after exposure to fire, it expands to form a dense, highly flexible, dense, non-cratered, pinhole-free, non-missing coating, highly connected, and water-resistant ceramicized heat-insulating carbon layer with a thickness of ≥2-5mm. This effectively guarantees the dual characteristics of fire-expanding heat insulation and normal flexibility and weather resistance of the open self-rolling fireproof braided tube 10, achieving the retention of the self-rolling structure and performance breakthrough of the open self-rolling fireproof braided tube 10.

[0051] In one embodiment, the modified bio-based fire-retardant and intumescent coating has an expansion ratio of ≥10 times.

[0052] In one embodiment, the catalyst includes at least one of bismuth neodecanoate, organozinc, dibutyltin dilaurate, and stannous octoate.

[0053] In one embodiment, the chain extender includes at least one of 1,4-butanediol, resorcinol bis(2-hydroxyethyl) ether, hydroquinone bis(hydroxyethyl) ether, 1,3-propanediol, and diethyldiaminotoluene.

[0054] In one embodiment, the braided self-winding layer is woven from PET and PP yarns to ensure that the braided self-winding layer has flexibility under normal conditions, realizes the self-winding function, has a wear resistance life of ≥1 million cycles / 500gf, good weather resistance with working temperature of -40℃ to 150℃, and meets the durability requirements under normal use conditions.

[0055] It is also understandable that the high strength and high elasticity of PET monofilament can effectively compensate for the lack of rigidity of PP monofilament, while the low cost and high flowability of PP monofilament can improve the processing and cost shortcomings of PET. Therefore, the braided self-winding layer obtained by mixing PET monofilament and PP monofilament has the characteristics of low cost, high strength and high elasticity, which is conducive to realizing the large-scale production of braided self-winding layers.

[0056] In one embodiment, the thickness of the braided self-winding layer is 0.25mm-0.65mm.

[0057] In one embodiment, the PET filament diameter is 0.1mm-0.35mm.

[0058] In one embodiment, the diameter of the polypropylene fiber monofilament is 0.1 mm to 0.5 mm.

[0059] like Figures 1 to 3 This disclosure also provides an open self-winding fireproof braided tube 10, comprising a braided self-winding layer and the modified bio-based fire-retardant coating described in any of the above embodiments, wherein the modified bio-based fire-retardant coating is formed on at least one side of the braided self-winding layer to form a modified bio-based fire-retardant coating 200.

[0060] In one embodiment, the braided self-winding layer has a wound inner side 130 and a wound outer side 140, and a modified bio-based fire-retardant and flame-inflating coating 200 is disposed on the wound outer side 140.

[0061] It is understandable that if the modified bio-based fire-retardant coating 200 is placed on the inner winding surface 130 of the braided self-winding layer, the modified bio-based fire-retardant coating 200 is prone to direct friction with the wire harness 20 during installation, resulting in a reduction in the fire-retardant and heat-insulating performance of the modified bio-based fire-retardant coating 200. Therefore, by placing the modified bio-based fire-retardant coating 200 on the outer winding surface 140 of the braided self-winding layer (woven from PET and PP filaments), on the one hand, direct friction between the modified bio-based fire-retardant coating 200 and the wire harness 200 is effectively avoided during installation, thereby ensuring the effective performance of the fire-retardant and heat-insulating performance of the modified bio-based fire-retardant coating 200; on the other hand, it ensures that the expansion space of the modified bio-based fire-retardant coating 200 is not restricted when exposed to fire, further ensuring the effective performance of the fire-retardant and heat-insulating performance of the modified bio-based fire-retardant coating 200.

[0062] In one embodiment, the diameter of the open self-winding fireproof braided tube 10 is 3mm-100mm, which can adapt to the needs of different specifications of wire harness 20 and improve the adaptability of the open self-winding fireproof braided tube 10.

[0063] In one embodiment, the open self-winding fireproof braided tube 10 includes a braided self-winding layer, an open overlapping area 110 is formed on one axial side of the braided self-winding layer, and a self-winding cavity 120 is formed in the braided self-winding layer. The self-winding cavity 120 is used to accommodate the wire harness 20, ensuring that the open self-winding fireproof braided tube 10 has open self-winding performance, thereby ensuring the ease of installation of the open self-winding fireproof braided tube 10.

[0064] This disclosure also provides a method for preparing an open-ended self-winding fireproof braided tube 10. First, a modified bio-based fire-retardant coating as described in any of the above embodiments is obtained. Next, the modified bio-based fire-retardant coating is coated onto one side of the braided self-winding layer to obtain a self-winding fireproof braided tube precursor. Finally, the self-winding fireproof braided tube precursor is cured and then shaped to obtain the open-ended self-winding fireproof braided tube 10. The above method can prepare an open-ended self-winding fireproof braided tube 10 that simultaneously possesses the dual properties of fire-induced expansion and heat insulation, as well as normal flexibility and weather resistance, through simple mixing and coating operations.

[0065] In one embodiment, the method for preparing the open self-winding fireproof braided tubing 10 includes some or all of the following steps: S101. Obtain the modified bio-based fire-retardant and intumescent flame-retardant coating described in any of the above embodiments. Mix 30-40 parts of bio-based phosphorus-containing polyol; 5-10 parts of isoflurane isocyanate; 20-25 parts of non-polyphosphate ammonium intumescent flame retardant; 8-20 parts of synergist; 0.03-0.2 parts of catalyst; and 1-5 parts of chain extender to obtain the modified bio-based fire-retardant and intumescent flame-retardant coating.

[0066] It should be noted that, due to the strong polar groups of non-polyphosphate intumescent flame retardants, if non-polyphosphate intumescent flame retardants are mixed with bio-based phosphorus-containing polyols and isoflurone isocyanates, the linear long-chain aliphatic hydrocarbons of the bio-based phosphorus-containing polyols are easily encapsulated, making it impossible to prepare bio-based phosphorus-containing polyols that simultaneously possess both polar and non-polar structures.

[0067] Therefore, in one embodiment, when mixing 30-40 parts of bio-based phosphorus-containing polyol; 5-10 parts of isoflurane isocyanate; 20-25 parts of non-ammonium polyphosphate intumescent flame retardant; 8-20 parts of synergist; 0.03-0.2 parts of catalyst; and 1-5 parts of chain extender, a portion of the medium-polarity solvent is first mixed with the non-ammonium polyphosphate intumescent flame retardant to obtain a non-ammonium polyphosphate intumescent flame retardant slurry. This allows the medium-polarity solvent to penetrate into the interparticle spaces of the non-ammonium polyphosphate intumescent flame retardant. Pre-wetting of the non-polyphosphate intumescent flame retardant weakens its surface polarity, thereby reducing the intensity of the polar interaction between the non-polyphosphate intumescent flame retardant and the bio-based phosphorus-containing polyol, and decreasing the probability of polar groups encapsulating the linear long-chain aliphatic hydrocarbons of the bio-based phosphorus-containing polyol. Next, a portion of a moderately polar solvent is mixed with the bio-based phosphorus-containing polyol, synergist, and chain extender at low speed to obtain mixture A. This mixture allows the linear long-chain aliphatic hydrocarbons of the bio-based phosphorus-containing polyol to fully expand, while also... To ensure the synergist preferentially occupies the non-polar regions of the bio-based phosphorus-containing polyol, it facilitates the expansion of the long-chain aliphatic hydrocarbons of the bio-based phosphorus-containing polyol and their occupation of their non-polar sites, preventing the polar groups of the subsequent non-polyphosphate ammonium intumescent flame retardant slurry from approaching and encapsulating the long-chain aliphatic hydrocarbons of the bio-based phosphorus-containing polyol. Subsequently, the catalyst is added to mixture A under stirring conditions, followed by filtration to obtain a homogeneous, non-agglomerated component A, which is set aside. Next, isoflurane isocyanate is mixed with a moderately polar solvent at low speed to obtain component B, which is also set aside. Thus, by preparing non-ammonium polyphosphate intumescent flame retardant slurry, component A, and component B separately, it is beneficial to subsequently prepare a modified bio-based fire-retardant intumescent flame retardant coating with uniform dispersion and incomplete encapsulation of linear long-chain aliphatic hydrocarbons of bio-based phosphorus-containing polyols. This facilitates the uniform spreading of the modified bio-based fire-retardant intumescent flame retardant coating on the surface of the woven self-rolled non-polar fibers, avoiding the problem of pinholes or missed coatings of bio-based phosphorus-containing polyols in the fiber gaps, and effectively reducing the probability of pinholes and missed coatings in the modified bio-based fire-retardant intumescent flame retardant coating.

[0068] It is also understandable that the added moderately polar organic solvent can effectively prevent the polyurethane prepolymer from entangled, ensuring that the viscosity of the final modified bio-based fire-retardant coating is maintained at 100 mPa·s-200 mPa·s. This ensures that the modified bio-based fire-retardant coating has good flowability and dispersibility. On the one hand, this facilitates subsequent coating operations and reduces clogging problems in the spraying or dipping process. On the other hand, it enables the modified bio-based fire-retardant coating to spread evenly and quickly in the woven self-rolling layer, which is conducive to forming an ultra-thin, highly flexible, dense modified bio-based fire-retardant coating 200 that is free of pinholes, craters, and missed coatings, has strong adhesion, and high water resistance.

[0069] In one embodiment, the catalyst is added to the mixture A under stirring conditions, and then filtered using a filter screen of 80-120 mesh to obtain a uniform and agglomerated component A.

[0070] In one embodiment, the moderately polar organic solvent includes at least one of butyl acetate, ethyl acetate, propylene glycol methyl ether acetate, and acetone.

[0071] In one embodiment, the use of a moderately polar organic solvent is 3 to 10 parts by weight.

[0072] In one embodiment, the synergist is nano-montmorillonite, carbon black, and silane coupling agent, which enables the added nano-montmorillonite, carbon black, and silane coupling agent to better expand the long-chain aliphatic hydrocarbons of bio-based phosphorus-containing polyols and occupy their non-polar sites.

[0073] S102. The modified bio-based fire-retardant and flame-inflating coating is applied to one side of the braided self-winding layer to obtain a self-winding fire-retardant braided tube precursor.

[0074] In one embodiment, when the modified bio-based fire-retardant and intumescent flame-retardant coating is applied to one side of the braided self-winding layer by dip coating or spray coating, the thickness of the modified bio-based fire-retardant and intumescent flame-retardant coating is controlled to be 0.1mm-0.5mm. This ensures that a small amount of the modified bio-based fire-retardant and intumescent flame-retardant coating is used to meet the flame-retardant performance requirements. This is beneficial for obtaining a thinner self-winding fireproof braided tube precursor. This ensures that the ultra-thin modified bio-based fire-retardant and intumescent flame-retardant coating 200 obtained by final curing does not damage the self-winding elasticity and flexibility of the braided self-winding layer, and can also ensure that an effective fire-retardant and intumescent heat insulation layer is formed after exposure to fire. This ensures that the open self-winding fireproof braided tube 10 has high flame-retardant performance.

[0075] In one embodiment, the process parameters for the spraying process are as follows: the spraying pressure is controlled at 10MPa-15MPa, the nozzle diameter is 0.38mm-0.55mm, the spraying distance is 20cm-25cm, and single-sided spraying is performed at a uniform speed.

[0076] In one embodiment, the modified bio-based fire-retardant coating is applied using a two-component polyurethane spraying device.

[0077] In one embodiment, before coating, a non-ammonium polyphosphate intumescent flame-retardant slurry is mixed with component A to obtain component A mixture. Then, component A mixture is mixed with component B using a two-component polyurethane spraying device to obtain a modified bio-based fire-retardant intumescent coating. It is worth noting that the prepared modified bio-based fire-retardant intumescent coating should be applied immediately.

[0078] In one embodiment, when the modified bio-based fire-retardant intumescent coating is applied to one side of the woven self-rolled layer, the coating is applied 1 to 3 times. The interval between each application is 10 to 20 minutes.

[0079] In one embodiment, the modified bio-based fire-retardant coating is applied to the outer side of the self-woven roll.

[0080] S103. The self-winding fireproof braided tube precursor is cured and then shaped to obtain the open self-winding fireproof braided tube 10.

[0081] In one embodiment, the curing conditions are: temperature of 60℃-80℃ and time of 1h-2h, to ensure that the modified bio-based fire-retardant coating can crosslink and cure under these temperature conditions to obtain the modified bio-based fire-retardant coating 200.

[0082] In one embodiment, the self-winding fireproof braided tube precursor, which has undergone curing treatment, is placed in a shaping mold for shaping and then cooled to room temperature to obtain an open self-winding fireproof braided tube 10.

[0083] In one embodiment, the shaping process at a temperature of 100℃-130℃ results in a circular tubular structure. It is understood that the 100℃-130℃ temperature keeps the braided self-winding layer and the modified bio-based fire-retardant intumescent coating in a flexible and malleable state; it is then wound into a circular tubular structure using a sizing mold, and subsequently cooled to room temperature by cold air for shaping. This allows the PET and PP fibers of the braided self-winding layer to regain rigidity and maintain the circular tube shape, resulting in a structurally stable, fire-resistant open-end self-winding fireproof braided tube 10.

[0084] In one embodiment, the modified bio-based fire-retardant coating 200 of the open self-winding fireproof braided tube 10 prepared in this disclosure will not peel off or crack when the bending radius is ≤6mm.

[0085] In one embodiment, the radial angle range of the overlapping area 110 is 60°-270°, ensuring that only a small force is needed to open the opening of the self-winding fireproof braided tubing 10 during installation, facilitating the insertion and removal of the wire harness 20 and subsequent maintenance. It also ensures the sealing of the overlapping area 110, ensuring that the self-winding fireproof braided tubing 10 maintains good weather resistance (-40℃-150℃), abrasion resistance (≥1 million cycles / 500gf), and corrosion resistance under normal conditions. In particular, with the use of the modified bio-based fire-retardant intumescent flame-retardant coating 200 disclosed herein, the flame retardant rating of the self-winding fireproof braided tubing 10 is improved to UL94V-0, far exceeding the existing UL94V-2 standard, while also meeting the flame retardant requirements of the automotive industry such as GB8410-2006.

[0086] like Figure 3 and Figure 5 As shown, this disclosure also provides a fireproof wire harness assembly, including the open self-winding fireproof braided tube 10 described in any of the above embodiments.

[0087] In one embodiment, an open overlapping area 110 is formed on one axial side of the braided self-winding layer of the open self-winding braided tube 10. The braided self-winding layer forms a self-winding cavity 120, which is used to accommodate the wire harness 20, ensuring that the open self-winding fireproof braided tube 10 has open self-winding performance, thereby ensuring the ease of installation of the open self-winding fireproof braided tube 10. Furthermore, since the modified bio-based fire-retardant intumescent flame-retardant coating 200 is disposed on the outer wall of the self-winding cavity 120, it is ensured that the wire harness 20 will not come into frictional contact with the modified bio-based fire-retardant intumescent flame-retardant coating 200 during installation, thus ensuring the effective performance of the fireproof and heat-insulating properties of the modified bio-based fire-retardant intumescent flame-retardant coating 200. On the other hand, it ensures that the expansion space of the modified bio-based fire-retardant intumescent flame-retardant coating 200 is not restricted when exposed to fire, further ensuring the effective performance of the fireproof and heat-insulating properties of the modified bio-based fire-retardant intumescent flame-retardant coating 200.

[0088] like Figure 4As shown, in one embodiment, the open self-winding fireproof braided tube 10 further includes a modified bio-based fireproof expansion flame retardant sub-coating 300. The braided self-winding layer 100 has a winding start end 150 and a winding end end 160. The overlapping area formed by the self-winding of the winding start end 150 and the winding end end 160 is the open overlap area 110. A modified bio-based fire-retardant and flame-inflating sub-coating 300 is disposed at the winding end 160 of the braided self-winding layer. The first end of the modified bio-based fire-retardant and flame-inflating sub-coating 300 is flush with one end of the braided self-winding layer, and the second end of the modified bio-based fire-retardant and flame-inflating sub-coating 300 is flush with the first end of the braided self-winding layer. In this way, while achieving more comprehensive fire-retardant and heat-insulating performance of the braided self-winding layer, the utilization rate of the modified bio-based fire-retardant and flame-inflating sub-coating 300 is also improved, thereby reducing the waste of the modified bio-based fire-retardant and flame-inflating sub-coating 300, and also improving the self-winding seal of the modified bio-based fire-retardant and flame-inflating sub-coating 300 on the open self-winding fireproof braided tube 10.

[0089] like Figure 4 As shown, in one embodiment, the width of the modified bio-based fire-retardant intumescent sub-coating 300 gradually increases from the end near the self-winding braid to the end away from the self-winding braid. This ensures that the bottom width of the modified bio-based fire-retardant intumescent sub-coating 300 is greater than the top width, allowing the bottom of the modified bio-based fire-retardant intumescent sub-coating 300 to fit well into the opening overlap area 110. Meanwhile, the top of the modified bio-based fire-retardant intumescent sub-coating 300 is easier to bend and will not detach or deform. Thus, the added modified bio-based fire-retardant intumescent sub-coating 300 does not affect the self-winding fire-retardant braid. Under the premise of the self-winding performance of the tube 10, it is also ensured that the key point of the modified bio-based fire-resistant and flame-retardant sub-coating 300 after expansion upon exposure to fire can be well close to the bottom of the modified bio-based fire-resistant and flame-retardant sub-coating 300. This ensures that the expanded modified bio-based fire-resistant and flame-retardant sub-coating 300 can still be well sealed to the opening overlap area 110. This effectively avoids the key point of the modified bio-based fire-resistant and flame-retardant sub-coating 300 deviating from the center after expansion upon exposure to fire, which would easily cause the expanded modified bio-based fire-resistant and flame-retardant sub-coating 300 to open the opening overlap area 110, resulting in the entry of heat or flames and failing to achieve good fireproof and heat insulation performance.

[0090] In one embodiment, the modified bio-based fire-retardant intumescent sub-coating 300 has a trapezoidal cross-section.

[0091] In one embodiment, the base length of the modified bio-based fire-retardant intumescent sub-coating 300 is 1.1-1.5 times the top length.

[0092] The following are some specific examples. When %, it refers to a percentage by weight. It should be noted that the following examples do not exhaustively list all possible scenarios, and unless otherwise specified, the materials used in the examples are commercially available. Example 1

[0093] 1) Castor oil (functionality 2.2, hydroxyl value 52mgKOH / g, molecular weight 2610, manufacturer: Vantrus) The bio-based phosphorus-containing polyol (model GR-50) and organophosphate diol (hydroxyl value 170mgKOH / g, phosphorus content 16%-18%, manufacturer Clariant, model ExolitOP550) were mixed at a mass ratio of 100:15, and then subjected to vacuum stirring and degassing treatment for 120 minutes to obtain bio-based phosphorus-containing polyol. 2) Modified bio-based fire-retardant and intumescent coatings; 2.1 Add 20 kg of melamine bicyclic cage-like phosphate (model Melais329) to 13.3 kg of butyl acetate, disperse at high speed for 8 min to prepare a uniform slurry, and obtain a non-polyphosphate ammonium intumescent flame retardant slurry for later use; 2.2. Add 35 kg of bio-based phosphorus-containing polyol, 1.5 kg of carbon black, 1.0 kg of chain extender (1,4-butanediol), and 0.2 kg of silane coupling agent (model KH-590) obtained in step 1) to a stirred tank and stir at low speed of 500 r / min for 5 min. Add the non-polyphosphate ammonium expanded flame retardant slurry from step 2.1, adjust the viscosity with an appropriate amount of butyl acetate, and continue stirring for 3 min to obtain mixed liquid A. Then add 0.05 kg of organic bismuth catalyst, stir at low speed of 500 r / min for 2 min, and filter through an 80 mesh filter to obtain a uniform and non-agglomerated component A for later use. 2.3 Add 7.1 kg of IPDI isoflurane isocyanate, 15.0 kg of montmorillonite, and 10.0 kg of PMA propylene glycol methyl ether acetate to a mixing tank, stir at 300 r / min for 5 min until homogeneous, and obtain component B for later use; 2.4 The A component mixture and the B component are mixed using a two-component polyurethane spraying equipment to obtain a modified bio-based fire-retardant and intumescent coating, which is then immediately applied for spraying.

[0094] 3) Spraying Under the conditions of spraying pressure controlled at 12MPa, nozzle diameter of 0.43mm, and spraying distance of 20cm, the modified bio-based fire-retardant and intumescent flame-retardant coating from step 2.4) is applied to the outer surface of the self-winding braided layer (braided from PET and PP filaments), and the coating thickness of the modified bio-based fire-retardant and intumescent flame-retardant coating is controlled at 0.1mm to obtain the precursor of the self-winding fire-retardant braided tube.

[0095] 4) Curing The self-winding fireproof braided tube precursor was baked at 60℃ for 2 hours to fix the modified bio-based fireproof intumescent flame-retardant coating on the outer surface of the self-winding braided layer (braided from PET and PP filaments). 5) Shaping operation The self-winding fireproof braided tube precursor obtained in step 4) is placed in a 100℃ shaping mold for shaping, and then cooled to room temperature to obtain an open self-winding fireproof braided tube. Example 2

[0096] 1) Dimeric diol (C36, functionality 2.0, hydroxyl value 200mgKOH / g, molecular weight 536, manufacturer Croda, model Pripol2033) and tris(dipropylene glycol) phosphite (hydroxyl value 395mgKOH / g, phosphorus content 7.2%, manufacturer Cangzhou Weida Chemical Co., Ltd., model P430) were mixed at a mass ratio of 100:10 and then subjected to vacuum stirring and degassing treatment for 120 minutes to obtain bio-based phosphorus-containing polyol; 2) Modified bio-based fire-retardant and intumescent coatings; 2.1 Add 20 kg of monocage melamine phosphate salt to 10.0 kg of acetone and disperse at high speed for 8 min to prepare a uniform slurry, which is a non-polyphosphate ammonium intumescent flame retardant slurry for later use; 2.2. Add 30 kg of bio-based phosphorus-containing polyol, 1.5 kg of carbon black, 1.1 kg of chain extender (hydroquinone dihydroxyethyl ether), and 0.1 kg of silane coupling agent (model KH-590) obtained in step 1) to a stirred tank and stir at low speed of 500 r / min for 5 min. Add the non-polyphosphate ammonium expanded flame retardant slurry from step 2.1, adjust the viscosity with an appropriate amount of acetone, and continue stirring for 3 min to obtain mixed liquid A. Then add 0.03 kg of organic zinc catalyst, stir at low speed of 300 r / min for 2 min, and filter through a 100-mesh filter to obtain a uniform and non-agglomerated component A for later use. 2.3 Add 12 kg of IPDI isoflurane isocyanate, 15.0 kg of montmorillonite, and 10.0 kg of PMA propylene glycol methyl ether acetate to a mixing tank, stir at 300 r / min for 5 min until homogeneous, and obtain component B for later use; 2.4 The A component mixture and the B component are mixed using a two-component polyurethane spraying equipment to obtain a modified bio-based fire-retardant and intumescent coating, which is then immediately applied for spraying.

[0097] 3) Spraying Under the conditions of spraying pressure controlled at 10MPa, nozzle diameter of 0.38mm, and spraying distance of 25cm, the modified bio-based fire-retardant and intumescent flame-retardant coating from step 2.4) is applied to the outer surface of the self-winding braided layer (braided from PET and PP filaments), and the coating thickness of the modified bio-based fire-retardant and intumescent flame-retardant coating is controlled at 0.2mm to obtain the precursor of the self-winding fire-retardant braided tube.

[0098] 4) Curing The self-winding fireproof braided tube precursor was baked at 70℃ for 2 hours to fix the modified bio-based fireproof intumescent flame-retardant coating on the outer surface of the self-winding braided layer (braided from PET and PP filaments). 5) Shaping operation The self-winding fireproof braided tube precursor obtained in step 4) is placed in a 120℃ shaping mold for shaping, and then cooled to room temperature to obtain an open self-winding fireproof braided tube. Example 3

[0099] 1) Soybean oil polyol (functionality 2.0, hydroxyl value 56mgKOH / g, molecular weight 1700, manufacturer USSC, model R2-052) and N,N-di(2-hydroxyethyl)aminomethylenephosphonic acid diethyl ester (hydroxyl value 450mgKOH / g, phosphorus content 13%, manufacturer Zhejiang Wansheng, model WSFR-6) were mixed at a mass ratio of 100:20, and then subjected to vacuum stirring and degassing treatment for 120 minutes to obtain bio-based phosphorus-containing polyol; 2) Modified bio-based fire-retardant and intumescent coatings; 2.1 Add 25 kg of melamine bicyclic cage-like phosphate (model Charguard329) to 12.5 kg of ethyl acetate and disperse at high speed for 8 min to prepare a uniform slurry, thus obtaining a non-polyphosphate ammonium intumescent flame retardant slurry for later use; 2.2. Add 40 kg of bio-based phosphorus-containing polyol, 1.5 kg of carbon black, 2.5 kg of chain extender (resorcinol bis(2-hydroxyethyl) ether), and 0.2 kg of silane coupling agent (model KH-590) obtained in step 1) to a stirred tank and stir at low speed of 500 r / min for 5 min. Add the non-polyphosphate ammonium expandable flame retardant slurry from step 2.1, adjust the viscosity with an appropriate amount of ethyl acetate, and continue stirring for 3 min to obtain mixed solution A. Then add 0.2 kg of dibutyltin dilaurate and stir at low speed of 300 r / min for 2 min. Filter through a 120 mesh filter to obtain a uniform and non-agglomerated component A for later use. 2.3 Add 12.25 kg of IPDI isoflurane isocyanate, 13.5 kg of nano-montmorillonite, and 9.0 kg of PMA propylene glycol methyl ether acetate to a mixing tank, stir at 300 r / min for 5 min until homogeneous, and obtain component B for later use; 2.4 The A component mixture and the B component are mixed using a two-component polyurethane spraying equipment to obtain a modified bio-based fire-retardant coating (viscosity 200 mPa·s), which is then immediately applied for spraying.

[0100] 3) Spraying Under the conditions of spraying pressure controlled at 15MPa, nozzle diameter of 0.55mm, and spraying distance of 22cm, the modified bio-based fire-retardant and intumescent coating from step 2.4) is applied to the outer surface of the self-winding braided layer (braided from PET and PP filaments), and the coating thickness of the modified bio-based fire-retardant and intumescent coating is controlled at 0.1mm to obtain the precursor of the self-winding fireproof braided tube.

[0101] 4) Curing The self-winding fireproof braided tube precursor was baked at 80℃ for 1.5h to fix the modified bio-based fireproof intumescent flame-retardant coating on the outer surface of the self-winding braided layer (braided from PET and PP filaments). 5) Shaping operation The self-winding fireproof braided tube precursor obtained in step 4) is placed in a 130℃ shaping mold for shaping, and then cooled to room temperature to obtain an open self-winding fireproof braided tube. Example 4

[0102] The difference from Example 1 is that the mixture of castor oil and organophosphate diol in step 1) at a mass ratio of 100:15 is replaced with a mixture of castor oil, dimer diol, soybean oil polyol and organophosphate diol at a mass ratio of 50:30:20:15; the melamine bicyclic cage phosphate in step 2.1 is replaced with 12.0 kg piperazine pyrophosphate and 8.0 kg pentaerythritol diphosphate salt; the amount of IPDI isoflurane isocyanate used in step 2.3 is replaced with 9.85 kg, and the rest remain unchanged.

[0103] Comparative Example 1 The difference from Example 1 is that the castor oil and organophosphate diol in step 1) are replaced with 100:4 by mass ratio instead of 100:15, while the rest remain the same.

[0104] Comparative Example 2 The difference from Example 1 is that the castor oil and organophosphate diol in step 1) are replaced with 100:22 by mass ratio instead of 100:15, while the rest remain the same.

[0105] Comparative Example 3 The difference from Example 1 is that the butyl acetate in steps 2.1 and 2.2 is omitted, while the rest remains the same.

[0106] Comparative Example 4 The difference from Example 1 is that the melamine bicyclic cage phosphate in step 2.1 is replaced with a common ammonium polyphosphate flame retardant, type II, n>1000, while the rest remain unchanged.

[0107] Comparative Example 5 The difference from Example 1 is that the melamine bicyclic cage phosphate in step 2.1 is removed, while the rest remains the same.

[0108] Comparative Example 6 The difference from Example 1 is that the amount of non-polyphosphate ammonium intumescent flame retardant in step 2.1 is adjusted to 10.0 kg, while the rest remain unchanged.

[0109] Comparative Example 7 The difference from Example 1 is that the amount of non-polyphosphate ammonium intumescent flame retardant in step 2.1 is adjusted to 35.0 kg, while the rest remain unchanged.

[0110] Comparative Example 8 The difference from Example 1 is that the synergists montmorillonite, carbon black, and coupling agent in steps 2.2 and 2.3 are removed, while the rest remain the same.

[0111] The flame retardant properties, connection strength, flexibility, water resistance, and wear life of the open self-winding fireproof braided tubing of the above embodiments and comparative examples were tested, and the experimental data are shown in Table 1 below.

[0112] Among them, flame retardant performance testing: Vertical flammability rating (UL94 / GB / T2408); Combustion performance meets V-0 level self-extinguishing requirement upon flameout; Limiting Oxygen Index (LOI) of the coating: 30-40; Expansion ratio: ≥10 times; Coating adhesion: Cross-cut test; Water resistance: (After immersion in water for 24h / 72h, the coating did not peel, crack, or blister); Self-winding stability: visual inspection method; Wear resistance life: ≥500 cycles of reciprocating friction, with no coating peeling or exposed fibers.

[0113] Table 1 As can be seen from Table 1 above, Examples 1-4, through the synergistic effect of the polar-nonpolar dual structure of bio-based phosphorus-containing polyols and non-polyphosphate ammonium intumescent flame retardants, achieved uniform spreading of modified bio-based fire-retardant and intumescent flame retardant coatings on the surfaces of different polar fibers. This facilitates the formation of ultra-thin, highly flexible, dense, pore-free, pinhole-free, non-missing coatings, highly interconnected, and highly water-resistant modified bio-based fire-retardant and intumescent flame retardant coatings. This ensures that the formed ultra-thin modified bio-based fire-retardant and intumescent flame retardant coatings do not damage the self-rolling elasticity and flexibility of the woven self-rolling layer, and can also ensure the formation of an effective fire-retardant and intumescent heat insulation layer after exposure to fire, so as to meet the fire safety requirements of extreme fire conditions and humid environments. Therefore, the comprehensive indicators of Examples 1-4 are significantly better than those of Comparative Examples 1-8, among which Example 4 has the best comprehensive indicators.

[0114] As can be seen from the comparison between Example 1 and Comparative Example 1, the overall performance of Comparative Example 1 is significantly worse than that of Example 1 because the content of organophosphate diol in Comparative Example 1 is too low.

[0115] As can be seen from the comparison between Example 1 and Comparative Example 2, the overall performance of Comparative Example 2 is significantly worse than that of Example 1 because the content of organophosphate diol in Comparative Example 2 is too high.

[0116] As can be seen from the comparison between Example 1 and Comparative Example 3, since Comparative Example 3 omits the solvent pre-dispersion step, the overall performance of Comparative Example 3 is significantly worse than that of Example 1.

[0117] As can be seen from the comparison between Example 1 and Comparative Example 4, since Comparative Example 4 uses a conventional flame retardant, its overall performance is significantly worse than that of Example 1.

[0118] As can be seen from the comparison between Example 1 and Comparative Examples 5-7, the overall performance of Comparative Examples 5-7 is significantly worse than that of Example 1 because the amount of non-ammonium polyphosphate intumescent flame retardant added in Comparative Examples 5-7 is not in the range of 20-25 parts.

[0119] As can be seen from the comparison between Example 1 and Comparative Example 8, since no synergist was added to Comparative Example 8, the overall performance of Comparative Example 8 was significantly worse than that of Example 1.

[0120] The embodiments described above are merely illustrative of several implementations of this disclosure, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the disclosed patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this disclosure, and these all fall within the protection scope of this disclosure. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A modified bio-based fire-retardant and intumescent flame-retardant coating, disposed on at least one side of a woven self-rolling layer, characterized in that, The woven self-winding layer is woven from two types of fiber monofilaments with significantly different polarities. The modified bio-based fire-retardant and intumescent flame-retardant coating comprises the following parts by weight: 30-40 parts of bio-based phosphorus-containing polyols; 5-10 parts of isoflurane isocyanate; 20-25 parts of non-polyphosphate ammonium intumescent flame retardant; Synergistic agent 8-20 parts; Catalyst: 0.03-0.2 parts; Chain extender 1-5 parts; The bio-based phosphorus-containing polyol is composed of bio-based polyol and phosphorus-containing polyol.

2. The modified bio-based fire-retardant and intumescent flame-retardant coating according to claim 1, characterized in that, The bio-based polyols include at least one of castor oil, dimer diol, and soybean oil polyols.

3. The modified bio-based fire-retardant and intumescent flame-retardant coating according to claim 1, characterized in that, The phosphorus-containing polyols include at least one of organophosphate diol, tris(dipropylene glycol) phosphite, diethyl N,N-di(2-hydroxyethyl)aminomethylenephosphonate, and dimethyl N,N-di(2-hydroxyethyl)aminomethylenephosphonate.

4. The modified bio-based fire-retardant and intumescent flame-retardant coating according to claim 1, characterized in that, The bio-based phosphorus-containing polyol is obtained by mixing bio-based polyol and phosphorus-containing polyol at a mass ratio of 100:(5~20).

5. The modified bio-based fire-retardant and intumescent flame-retardant coating according to claim 1, characterized in that, The synergist includes at least one of nano-montmorillonite, carbon black, and silane coupling agents.

6. The modified bio-based fire-retardant and intumescent flame-retardant coating according to claim 1, characterized in that, The non-polyphosphate intumescent flame retardant includes at least one of melamine bicyclic cage phosphate, monocage phosphate melamine salt and tricage phosphate melamine salt, piperazine pyrophosphate, and pentaerythritol diphosphate salt; and / or The modified bio-based fire-retardant and intumescent coating has a thickness of 0.1 mm to 0.5 mm; and / or, The woven self-winding layer is woven from PET and PP yarns.

7. An open-ended self-winding fireproof braided tubing, characterized in that, Includes woven self-winding layers and modified bio-based fire-retardant and intumescent coatings as described in any one of claims 1-6.

8. A method for preparing an open-ended self-winding fireproof braided tube, characterized in that, Includes the following steps: Obtain the modified bio-based fire-retardant and intumescent flame-retardant coating as described in any one of claims 1-6; The modified bio-based fire-retardant and flame-inflating coating is applied to one side of the braided self-winding layer to obtain a self-winding fireproof braided tube precursor. The self-winding fireproof braided tube precursor is cured and then shaped to obtain the open self-winding fireproof braided tube.

9. The method for preparing open-end self-winding fireproof braided tubing according to claim 8, characterized in that, The steps for obtaining the modified bio-based fire-retardant and intumescent flame-retardant coating further include the following steps: adding a moderately polar organic solvent to adjust the viscosity of the modified bio-based fire-retardant and intumescent flame-retardant coating to 200 mPa·s-500 mPa·s; and / or, The curing conditions are: temperature 60℃-80℃; time 1h-2h.

10. A fireproof wiring harness assembly, characterized in that, Includes the open self-winding fireproof braided tubing as described in claim 7.

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