A flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material, and a method for preparing the same and use thereof

Abstract

The present application provides a raw material containing decabromobiphenyl ethane flame-retardant polyurethane composition and its preparation method and application, which solves the technical problems that the existing bromine-antimony type flame-retardant system harms human health, pollutes the environment, and the raw material is a powder product, and the addition and use are not convenient enough; the flame-retardant polyurethane composition comprises raw material components: decabromobiphenyl ethane, brominated cashew phenol, flame-retardant synergist, polyether polyol, polymethylene polyphenyl isocyanate, and processing aid; the preparation method of the flame-retardant polyurethane composition comprises the following steps: S1, weighing each raw material component according to weight parts; S2, mixing decabromobiphenyl ethane, brominated cashew phenol, flame-retardant synergist, polyether polyol, and processing aid at a certain temperature to obtain white material; S3, taking polymethylene polyphenyl isocyanate as black material, mixing the white material with the black material to foam, and obtaining the flame-retardant polyurethane composition; and the flame-retardant polyurethane composition can be widely applied to the field of polyurethane foam flame-retardant technology.

Description

Technical Field

[0001] This application relates to the field of flame retardant polyurethane foam technology, and in particular to a flame retardant polyurethane composition containing decabromodiphenyl ethane as a raw material, its preparation method, and its application. Background Technology

[0002] Among the many types of polyurethane materials, polyurethane foam is widely used in furniture, automobiles, bedding, and building insulation materials due to its excellent thermal insulation, water resistance, and high chemical stability. Polyurethane foam is mainly prepared from polyols and polyisocyanates, and its limiting oxygen index is usually only 17% to 18%, making it a flammable product. Its large surface area and good air permeability can accelerate the spread of fire.

[0003] Currently, flame-retardant modification of polyurethane foam materials mainly employs the addition of additive or reactive flame retardants, with the bromine-antimony type system remaining the most common and effective. Bromine-antimony type flame retardant systems are widely popular due to their excellent performance and cost-effectiveness in gas-phase flame retardancy. Taking decabromodiphenyl ethane, a representative bromine-based flame retardant, as an example, adding antimony trioxide can achieve a synergistic effect between bromine and antimony, significantly improving the flame-retardant efficiency of the system and reducing the amount of flame retardant used. However, there are two main problems: firstly, most bromine-based flame retardant raw materials are derived from petrochemical products, posing health risks and environmental pollution; secondly, raw materials such as decabromodiphenyl ethane and antimony trioxide are powder products, making their addition and use inconvenient, thus affecting the molding process and overall toughness of the polyurethane foam. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the above-mentioned technology and provide a flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material, its preparation method, and its application.

[0005] Therefore, the present invention provides a flame-retardant polyurethane composition containing decabromodiphenyl ethane as raw material, comprising the following raw material components: decabromodiphenyl ethane, brominated cashew phenol, flame retardant synergist, polyether polyol, polymethylene polyphenyl isocyanate (PAPI), and processing aids.

[0006] Preferably, the raw material components, by weight, consist of 1.5 to 4.5 parts of decabromodiphenyl ethane and 1.5 to 6 parts of brominated cashew phenol; wherein, by mass percentage, the raw material components require that decabromodiphenyl ethane be 2.96 to 8.88% and brominated cashew phenol be 2.96 to 11.84%. Other raw material components and their proportions, such as flame retardant synergists, polyether polyols, polymethylene polyphenyl isocyanates, and processing aids, can be adjusted according to actual conditions.

[0007] Preferably, the raw material components, by weight, are: 2 parts flame retardant synergist; 20 parts polyether polyol; 22 parts polymethylene polyphenyl isocyanate; and 0.68 parts processing aid.

[0008] Preferably, the bromine content of brominated cashew phenol is ≥30%.

[0009] Preferably, the bromine content of brominated cashew phenol is 41% to 62%.

[0010] Preferably, brominated cashew phenol has a Brookfield viscosity of ≤7850 CPS at 25°C.

[0011] Preferably, the mass ratio of decabromodiphenyl ethane to brominated cashew phenol is 1:1.

[0012] Preferably, the flame retardant synergist includes antimony oxide or antimony metal salt.

[0013] Preferably, the antimony oxide includes one of antimony trioxide, antimony tetroxide, and antimony pentoxide; the antimony metal salt includes sodium antimonate.

[0014] Preferably, the processing aids, by weight, include: 0.16 parts water-soluble silicone oil, 0.5 parts water, 0.01 parts triethylenediamine, and 0.01 parts dibutyltin dilaurate.

[0015] A method for preparing a flame-retardant polyurethane composition containing decabromodiphenyl ethane as described in any one of the above claims comprises the following steps:

[0016] Step S1. Weigh each raw material component according to its weight parts;

[0017] Step S2. Mix the decabromodiphenyl ethane, brominated cashew phenol, flame retardant synergist, polyether polyol, and processing aid weighed in step S1 at a certain temperature to obtain the white material;

[0018] Step S3. The polymethylene polyphenyl isocyanate weighed in step S1 is used as the black material. The white material obtained in step S2 is mixed with the black material and foamed to obtain a flame-retardant polyurethane composition.

[0019] Preferably, the temperature in step S2 is 25℃±2℃.

[0020] Preferably, brominated cashew phenol is the bromination reaction product of cashew phenol component, bromine component, and additive component. Cashew phenol, possessing reactive phenolic hydroxyl groups and unsaturated long alkyl chains, is an agricultural byproduct extracted from natural cashew nut shell oil. It boasts advantages such as abundant source, low price, and renewability, while also being easily modified and exhibiting good hydrophobicity and chemical resistance, playing a crucial role in replacing petroleum-based feedstocks. Typically, cashew phenol is a mixture of four alkylphenols with different degrees of saturation: 3% saturated hydrocarbon cashew phenol, 42% mono-olefin cashew phenol, 17% diene-olefin cashew phenol, and 38% tri-olefin cashew phenol. Its structural diagram is shown below:

[0021]

[0022] Preferably, the method for preparing brominated cashew phenol includes: dissolving cashew phenol in an organic solvent, adding bromine to the solution, reacting completely, washing the organic phase with water and distilling off the organic solvent to obtain brominated cashew phenol.

[0023] Preferably, the method for preparing brominated cashew nut phenol includes: weighing 285-305 parts of cashew nut phenol and dissolving it in 295-400 parts of organic solvent, controlling the temperature of the reaction solution at 25℃±2℃, and adding 150-645 parts of bromine dropwise; after the bromine addition is completed, stirring the reaction solution at 25℃±2℃; after the reaction is completed, thoroughly washing the product with water, and distilling to remove the organic solvent to obtain brominated cashew nut phenol.

[0024] Preferably, brominated cashew phenol has the following structural formula (I):

[0025]

[0026] Where X and Y are both positive integers; R is the C15 alkyl side chain of cashew phenol.

[0027] Preferably, brominated cashew phenol contains at least one aliphatic bromine.

[0028] Preferably, the method for preparing low-viscosity brominated cashew phenol includes: dissolving brominated cashew phenol in an organic solvent, adding acetic anhydride, reacting under the action of p-toluenesulfonic acid, washing the organic phase with water after complete reaction, separating and removing water, and distilling off the organic solvent under reduced pressure to obtain low-viscosity brominated cashew phenol.

[0029] Preferably, brominated cashew phenol has the following structural formula (II):

[0030]

[0031] Where X and Y are both positive integers; R is the C15 alkyl side chain of cashew phenol; and Q is the alkyl side chain.

[0032] Preferably, the organic solvent is one or more of dichloromethane, dichloroethane, dichloropropane, trichloroethane, trichloromethane, and carbon tetrachloride.

[0033] The flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material, or the flame-retardant polyurethane composition containing decabromodiphenyl ethane prepared by the method described in any of the above-mentioned claims, is used in the preparation of flame-retardant polyurethane foam.

[0034] This invention provides a flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material, its preparation method, and its application, which have the following beneficial effects:

[0035] (1) Using brominated cashew phenol as a raw material as a flame retardant has several advantages. First, brominated cashew phenol can replace or partially replace petroleum-based bromine flame retardants such as decabromodiphenyl ethane, which changes the limitation that all flame-retardant polyurethane compositions are derived from petroleum. Using brominated cashew phenol as a raw material for preparing flame-retardant polyurethane foam has the advantages of safety and environmental protection. Second, brominated cashew phenol is a low-viscosity liquid with good fluidity. It can be used in conjunction with other raw materials during the preparation process. Compared with the existing technology, it is more convenient to add powders such as decabromodiphenyl ethane and antimony trioxide, thereby ensuring the molding process of polyurethane foam and the overall toughness of the foam.

[0036] (2) It is prepared by compounding decabromodiphenyl ethane and brominated cashew phenol. On the one hand, the introduction of brominated cashew phenol reduces the content of petroleum-based components in the flame-retardant polyurethane composition and increases the content of bio-based components. On the other hand, the bromine in brominated cashew phenol exists on both the benzene ring and the C15 long chain of cashew phenol. That is, the brominated cashew phenol of the present invention is both an aliphatic bromine derivative flame retardant and an aromatic bromine derivative flame retardant. It is a bio-based flame retardant that contains both aliphatic bromine and aromatic bromine.

[0037] (3) Decabromodiphenyl ethane and brominated cashew phenol, together with flame retardant synergists, jointly retard polyurethane foam materials, possessing two flame retardant synergistic systems: bromo-bromo synergy and bromo-antimony synergy. These systems can exert flame retardant effects at different stages of combustion. Initially, in the early stages of the flame retardant process, due to the low bond strength and stability of aliphatic bromine derivatives, they are easily decomposed by heat. Therefore, the bromine on the C15 long chain of brominated cashew phenol preferentially exerts its flame retardant effect, capturing free radicals during material decomposition, thereby delaying or inhibiting the combustion chain reaction. Simultaneously, the released HBr is itself a flame-retardant gas that can cover the surface of the material, acting as a barrier and diluting the oxygen concentration. Subsequently, as the temperature rises, the aromatic bromine derivatives continue to exert their flame retardant effect, releasing HBr gas in the later stages of combustion to block the spread of combustion. Ultimately, the flame-retardant polyurethane composition of this invention possesses two flame retardant synergistic systems: bromo-bromo synergy and bromo-antimony synergy, which can exert flame retardant effects at different stages of combustion, thus greatly improving the flame retardant efficiency of polyurethane foam. Furthermore, the flame-retardant polyurethane composition of this invention features high flame retardant efficiency, low viscosity, low cost, and low powder consumption. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application.

[0039] Figure 1 Infrared spectral analysis results for the cashew phenol products and brominated cashew phenol 3A, brominated cashew phenol 4A, brominated cashew phenol 5A and brominated cashew phenol 6A prepared in Example 1. Detailed Implementation

[0040] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0041] Unless otherwise specified, the methods used in this invention are conventional methods; the raw materials and equipment used are conventional commercially available products unless otherwise specified.

[0042] The decabromodiphenyl ethane was supplied by Shandong Tianyi Chemical Co., Ltd., with a bromine content of 82%.

[0043] Cashew phenol was purchased from Wuhan Lanabai Pharmaceutical Chemical Co., Ltd., with a purity greater than 99%;

[0044] Bromine was purchased from Shandong Bangao Chemical Co., Ltd.

[0045] Antimony trioxide was purchased from Zibo Shengke Flame Retardant Materials Co., Ltd.

[0046] The polyether polyol was purchased from Changzhou Zhuolian Zhichuang Polymer Materials Technology Co., Ltd.

[0047] Polymethylene polyphenyl isocyanate was purchased from Changzhou Zhuolian Zhichuang Polymer Materials Technology Co., Ltd.

[0048] Acetic anhydride was purchased from Shandong Jiachi New Chemical Co., Ltd.

[0049] The viscometer model is NDJ-8S, rotor #1, purchased from Shanghai Lichen Bangxi Instrument Technology Co., Ltd.

[0050] Polyurethane foam formulation calculation:

[0051] The molecular structure of rigid polyurethane foam consists of soft and hard segments. The soft segments are derived from polyols, while the hard segments are derived from polyisocyanates. The reaction of isocyanate groups (-NCO), hydroxyl groups (-OH), amino groups (-NH2), and water produces urethane bonds (-NHCOO-), urea bonds (-HNCONH-), and carbamic acid, respectively. Among these, carbamic acid is very unstable and immediately decomposes into amino groups and carbon dioxide. This is also the reaction principle of chemical blowing agents.

[0052] During the polyurethane foaming process, the active functional groups in the reactive flame retardant react chemically with the polyurethane and bind to the polyurethane macromolecular chain in the form of chemical bonds. This introduces flame retardant elements or groups or generates covalent bonds with higher bond energy, thereby improving the flame retardant performance of the polyurethane.

[0053] 1. Calculation of the amount of polyisocyanate and polyol used:

[0054] (1) Equivalent (E) = Relative molecular mass (M) / Functionality (f)

[0055] (2) Hydroxyl value of polyols or hydroxyl compounds: refers to the number of milligrams of potassium hydroxide equivalent to the hydroxyl content in 1g of polyol or hydroxyl compound. Hydroxyl value (mgKOH / g) = 56.1 × 1000 / polyol equivalent

[0056] (3) Polyisocyanate equivalent

[0057] Polyisocyanate equivalent = 42.02 × 100% / (mass fraction of polyisocyanate group)

[0058] (4) Polyisocyanate requirement

[0059] Polyisocyanate required per serving of hydroxyl substance = equivalent polyisocyanate / equivalent hydroxyl substance

[0060] 2. Calculation of catalyst dosage: Catalyst dosage (g) = Polyol dosage (kg) / Mass ratio × 0.6;

[0061] 3. Calculation of foaming agent dosage: Foaming agent dosage (g) = Polyol dosage (kg) / Mass ratio × 5;

[0062] 4. Calculation of auxiliary agent dosage: Auxiliary agent dosage (g) = Polyol dosage (kg) / Mass ratio × 3;

[0063] Here, "mass ratio" refers to the percentage of polyisocyanates in the polyol.

[0064] 5. Precautions for formula calculation

[0065] (1) The hydroxyl value, moisture content, acid value and other indicators of polyols should be measured in practice to ensure the accuracy of the calculation.

[0066] (2) The moisture content of other components should also be considered, especially when adding fillers.

[0067] (3) The active groups in the additives, such as amino groups and hydroxyl groups, should also be included in the calculation of the polyisocyanates they consume.

[0068] During use, the theoretical dosage is only a reference value. The optimal ratio needs to be determined by combining and examining the actual physical properties and flame retardant properties of the polyurethane foam.

[0069] Example

[0070] Example 1:

[0071] Example 1 provides a method for preparing brominated cashew nut shells, and four brominated cashew nut shell products with different bromine contents are prepared, designated as 3A, 4A, 5A and 6A respectively.

[0072] (1) Preparation of brominated cashew phenol 3A:

[0073] Weigh 285 parts of cashew nut alcohol and dissolve it in 400 parts of dichloromethane, an organic solvent. Add the solution to a four-necked flask, install a mechanical stirrer, reflux condenser, and thermometer (with the thermometer submerged below the liquid surface), and maintain the reaction temperature at 25℃±2℃. Add 150 parts of bromine dropwise using a dropping funnel, controlling the dropping rate, and complete the addition within 1-2 hours. Then, continue stirring the reaction mixture at 25℃±2℃ for 1.5-2.5 hours. Afterward, wash the product with water at 25℃±2℃ to separate the layers. Collect the lower organic phase and repeat the washing process 3-5 times. Finally, distill the organic phase at atmospheric pressure to remove the solvent, yielding brominated cashew nut alcohol 3A.

[0074] (2) Preparation of brominated cashew phenol 4A:

[0075] The preparation process differs from that of brominated cashew phenol 3A in that 295 parts cashew phenol, 500 parts dichloromethane, and 312 parts bromine are used to finally obtain brominated cashew phenol 4A; the other contents are the same and will not be repeated here.

[0076] (3) Preparation of brominated cashew phenol 5A:

[0077] The preparation process differs from that of brominated cashew phenol 3A in that 300 parts cashew phenol, 600 parts dichloromethane, and 476 parts bromine are used to finally obtain brominated cashew phenol 5A; the other contents are the same and will not be repeated here.

[0078] (4) Preparation of brominated cashew 6A:

[0079] The preparation process differs from that of brominated cashew phenol 3A in that 305 parts cashew phenol, 600 parts dichloromethane, and 645 parts bromine are used to finally obtain brominated cashew phenol 6A; the other contents are the same and will not be repeated here.

[0080] The bromine content (referring to "4.2 Determination of Bromine Content" in test standard Q / 0700STY103-2019) and Brookfield viscosity (referring to "5.4 Operating Procedures" in test standard GB / T 11145-2014) of the above four brominated cashew phenol products are shown in Table 1.

[0081] Table 1. Test data on bromine content and viscosity of four types of brominated cashew phenols.

[0082]

[0083] To further verify the successful synthesis of brominated cashew phenols with different bromine contents, the four types of brominated cashew phenols with different bromine contents obtained in Example 1 were characterized by infrared spectroscopy. The resulting infrared spectra are shown below. Figure 1 As shown.

[0084] from Figure 1 The infrared spectrum of Example 1 shows that at 3010 cm⁻¹ -1 The infrared absorption peak at 1590 cm⁻¹ is the CH stretching vibration peak on C=C. -1 1457cm -1 The infrared absorption peak at 780 cm⁻¹ is the C=C stretching vibration peak on the aromatic ring skeleton and unsaturated double bonds. -1 692cm -1 The infrared absorption peak at this point is an out-of-plane bending vibration absorption peak of CH, indicating that it is a 1,3 disubstituted benzene ring. The presence of the above functional groups indicates the main structure of cashew phenol.

[0085] from Figure 1As can be seen from the infrared spectrum of Example 1, compared with the cashew phenol product, brominated cashew phenol 3A with a bromine content of 30.03% and brominated cashew phenol 4A with a bromine content of 40.95% show higher chromaticity at 3010 cm⁻¹. -1 The decrease in the infrared absorption peak at 735 cm⁻¹ indicates that some of the double bonds in the C15 chain of cashew nutshellol underwent an addition reaction. Simultaneously, brominated cashew nutshellol 3A and brominated cashew nutshellol 4A showed a decrease in the infrared absorption peak at 735 cm⁻¹. -1 A strong infrared absorption peak appears, which is the absorption peak of the 1, 3, 5 trisubstituted benzene ring. The changes in the infrared absorption peaks indicate that at least one bromine has been introduced into the benzene ring of brominated cashew phenol 3A with a bromine content of 30.03% and brominated cashew phenol 4A with a bromine content of 40.95%. At the same time, one or two bromines have also been introduced into some double bonds on the C15 long chain of cashew phenol, and some double bonds have not participated in the reaction.

[0086] from Figure 1 As can be seen from the infrared spectrum of Example 1, compared with the cashew phenol product, brominated cashew phenol 3A, and brominated cashew phenol 4A, brominated cashew phenol 5A and brominated cashew phenol 6A have a higher infrared spectrum at 3010 cm⁻¹. -1 The disappearance of the infrared absorption peak at 735 cm⁻¹ indicates that all double bonds on the C15 chain of cashew nutshellol have undergone addition reactions. Simultaneously, brominated cashew nutshellol 5A and brominated cashew nutshellol 6A show absorption peaks at 735 cm⁻¹. -1 The strong absorption peak at the specified position still exists, proving that the benzene ring of cashew nutshellol still has 1, 3, 5 trisubstituted absorption peaks. The changes in the combined infrared absorption peaks prove that at least one bromine has been introduced into the benzene ring of both cashew nutshellol 5A (54.50% bromine content) and cashew nutshellol 6A (62.00% bromine content). Simultaneously, all double bonds on the C15 long chain of cashew nutshellol have undergone addition reactions, introducing at least two bromines at the double bond positions.

[0087] Example 2:

[0088] Example 2 provides a method for preparing low-viscosity brominated cashew phenol, comprising the following preparation steps:

[0089] 750 parts of brominated cashew phenol 5A prepared in Example 1 were dissolved in 900 parts of dichloromethane, an organic solvent, and added to a four-necked flask. A mechanical stirrer, reflux condenser, and thermometer were installed. Then, 110 parts of acetic anhydride and 3 parts of p-toluenesulfonic acid were added, and the mixture was reacted at 30°C for 2 hours. After the reaction, the mixture was washed 3-5 times with water, separated, and the organic solvent was distilled off under reduced pressure at a controlled temperature of 50°C-80°C to obtain low-viscosity brominated cashew phenol. The bromine content of the low-viscosity brominated cashew phenol product was measured to be 54.25%, almost identical to that of brominated cashew phenol 5A. The Brookfield viscosity of the low-viscosity brominated cashew phenol product at 25°C was measured to be 2250 CPS, classifying it as a low-viscosity liquid flame retardant product.

[0090] Example 3:

[0091] Example 3 provides a method for preparing a flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material, comprising the following preparation steps:

[0092] (1) Preparation of flame-retardant polyurethane composition white material:

[0093] Preheat the balance for at least 5 minutes, and calibrate if necessary. First, place the disposable plastic cup on the balance. According to the formula design, quantitatively add decabromodiphenyl ethane, brominated cashew phenol 3A prepared in Example 1, antimony trioxide, polyether polyol, processing aid water-soluble silicone oil, distilled water, triethylenediamine, and dibutyltin dilaurate into the disposable plastic cup. Set the temperature of the constant temperature device to control the temperature of the liquid at 25℃±2℃ (if using a water bath constant temperature, pay attention to protecting the raw materials from water absorption). Then stir and mix at 600r / min for 2 minutes to obtain the flame-retardant polyurethane composition white material; the specific reagent addition amount of the formula design is shown in Table 2.

[0094] (2) Preparation of flame-retardant polyurethane foam composition:

[0095] Polymethylene polyphenyl isocyanate (PAPI) is used as the black component in the flame-retardant polyurethane composition. Add the black component to a disposable plastic cup containing the white component according to the designed dosage. First, slowly stir the mixture (while simultaneously starting a stopwatch) to avoid splashing and affecting the ratio. After 2-3 seconds, stir at full speed for 8-10 seconds (the time for these two steps should be minimized). Then, quickly pour the stirred material into a clean large plastic cup or a wooden box lined with a thin film, allowing it to foam freely. After foaming stops, place it in a natural environment to continue the reaction for 24 hours.

[0096] Table 2 Experimental Formulations of Flame-Retardant Polyurethane Compositions 1

[0097]

[0098] Example 4:

[0099] Example 4 provides a method for preparing a flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material, comprising the following preparation steps:

[0100] (1) Preparation of flame-retardant polyurethane composition white material:

[0101] Preheat the balance for at least 5 minutes, and calibrate if necessary. First, place the disposable plastic cup on the balance. According to the formula design, quantitatively add decabromodiphenyl ethane, brominated cashew phenol 4A prepared in Example 1, antimony trioxide, polyether polyol, processing aid water-soluble silicone oil, distilled water, triethylenediamine, and dibutyltin dilaurate into the disposable plastic cup. Set the temperature of the constant temperature device to control the temperature of the liquid at 25℃±2℃ (if using a water bath constant temperature, pay attention to protecting the raw materials from water absorption). Then stir and mix at 600r / min for 2 minutes to obtain the flame-retardant polyurethane composition white material; the specific reagent addition amount of the formula design is shown in Table 3.

[0102] (2) Preparation of flame-retardant polyurethane foam composition:

[0103] Polymethylene polyphenyl isocyanate (PAPI) was used as the black material in the flame-retardant polyurethane composition; other aspects of the preparation of the flame-retardant polyurethane composition foam were the same as in step (2) of Example 3, and will not be repeated here.

[0104] Table 3 Experimental Formulations of Flame-Retardant Polyurethane Compositions 2

[0105]

[0106] Example 5:

[0107] Example 5 provides a method for preparing a flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material, comprising the following preparation steps:

[0108] (1) Preparation of flame-retardant polyurethane composition white material:

[0109] Preheat the balance for at least 5 minutes, and calibrate if necessary. First, place the disposable plastic cup on the balance. According to the formula design, quantitatively add decabromodiphenyl ethane, brominated cashew phenol 5A prepared in Example 1, antimony trioxide, polyether polyol, processing aid water-soluble silicone oil, distilled water, triethylenediamine, and dibutyltin dilaurate into the disposable plastic cup. Set the temperature of the constant temperature device to control the temperature of the liquid at 25℃±2℃ (if using a water bath constant temperature, pay attention to protecting the raw materials from water absorption). Then stir and mix at 600r / min for 2 minutes to obtain the flame-retardant polyurethane composition white material; the specific reagent addition amount of the formula design is shown in Table 4.

[0110] (2) Preparation of flame-retardant polyurethane foam composition:

[0111] Polymethylene polyphenyl isocyanate (PAPI) was used as the black material in the flame-retardant polyurethane composition; other aspects of the preparation of the flame-retardant polyurethane composition foam were the same as in step (2) of Example 3, and will not be repeated here.

[0112] Table 4 Experimental Formulations of Flame-Retardant Polyurethane Compositions 3

[0113]

[0114]

[0115] Example 6:

[0116] Example 6 provides a method for preparing a flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material, comprising the following preparation steps:

[0117] (1) Preparation of flame-retardant polyurethane composition white material:

[0118] Preheat the balance for at least 5 minutes, and calibrate if necessary. First, place the disposable plastic cup on the balance. According to the formula design, quantitatively add decabromodiphenyl ethane, brominated cashew phenol 6A prepared in Example 1, antimony trioxide, polyether polyol, processing aids water-soluble silicone oil, distilled water, triethylenediamine, and dibutyltin dilaurate into the disposable plastic cup. Set the temperature of the constant temperature device to control the temperature of the liquid at 25℃±2℃ (if using a water bath constant temperature, pay attention to protecting the raw materials from water absorption). Then, stir and mix at 600r / min for 2 minutes to obtain the flame-retardant polyurethane composition white material; the specific reagent addition amounts of the formula design are shown in Table 5.

[0119] (2) Preparation of flame-retardant polyurethane foam composition:

[0120] Polymethylene polyphenyl isocyanate (PAPI) was used as the black material in the flame-retardant polyurethane composition; other aspects of the preparation of the flame-retardant polyurethane composition foam were the same as in step (2) of Example 3, and will not be repeated here.

[0121] Table 5 Experimental formulations of flame-retardant polyurethane compositions 4

[0122]

[0123]

[0124] Comparative Example 1:

[0125] Comparative Example 1 provides a method for preparing a flame-retardant polyurethane composition, comprising the following preparation steps:

[0126] (1) Preparation of flame-retardant polyurethane composition white material:

[0127] Preheat the balance for at least 5 minutes, and calibrate if necessary. First, place the disposable plastic cup on the balance. According to the formula design, quantitatively add the polyether polyol, processing aids (water-soluble silicone oil), distilled water, triethylenediamine, and dibutyltin dilaurate into the disposable plastic cup. Set the temperature of the constant temperature device to control the temperature of the liquid at 25℃±2℃ (if using a water bath constant temperature, pay attention to protecting the raw materials from water absorption). Then, stir and mix at 600r / min for 2 minutes to obtain the flame-retardant polyurethane composition white material; the specific reagent addition amounts for the formula design are shown in Table 6.

[0128] (2) Preparation of flame-retardant polyurethane foam composition:

[0129] Polymethylene polyphenyl isocyanate (PAPI) was used as the black material in the flame-retardant polyurethane composition; other aspects of the preparation of the flame-retardant polyurethane composition foam were the same as in step (2) of Example 3, and will not be repeated here.

[0130] Table 6 Comparative Experimental Formulations of Flame-Retardant Polyurethane Compositions 1

[0131]

[0132] Comparative Example 2:

[0133] Comparative Example 2 provides a method for preparing a flame-retardant polyurethane composition, comprising the following preparation steps:

[0134] (1) Preparation of flame-retardant polyurethane composition white material:

[0135] Preheat the balance for at least 5 minutes, calibrating if necessary. First, place the disposable plastic cup on the balance. According to the formula, quantitatively add decabromodiphenyl ethane, antimony trioxide, polyether polyol, processing aids (water-soluble silicone oil), distilled water, triethylenediamine, and dibutyltin dilaurate into the disposable plastic cup. Set the temperature of the thermostat to 25℃±2℃ (if using a water bath, ensure the raw materials are protected against water absorption). Then, stir and mix at 600 rpm for 2 minutes to obtain the flame-retardant polyurethane composition white material. The specific reagent addition amounts are shown in Table 7.

[0136] (2) Preparation of flame-retardant polyurethane foam composition:

[0137] Polymethylene polyphenyl isocyanate (PAPI) was used as the black material in the flame-retardant polyurethane composition; other aspects of the preparation of the flame-retardant polyurethane composition foam were the same as in step (2) of Example 3, and will not be repeated here.

[0138] Table 7 Comparative Experimental Formulations of Flame-Retardant Polyurethane Compositions 2

[0139]

[0140] Standard samples were prepared for LOI testing for Examples 3-6 and Comparative Examples 1 and 2, respectively.

[0141] For the LOI foam material testing standard, the standard dimensions of the specimen (length × width × thickness) should be 70-150mm × 10±0.5mm × 10±0.5mm. (Test standard: GB / T2406.3-2022 standard, determination of limiting oxygen index of foamed plastics)

[0142] Test method: The standard sample is vertically clamped in a transparent combustion cylinder containing an upward-flowing mixture of oxygen and nitrogen in a specific ratio. The upper part of the sample is ignited, and the subsequent combustion phenomenon is observed. The duration of combustion or the distance burned is recorded. If the combustion time exceeds 3 minutes or the flame front exceeds the 50mm mark, the oxygen concentration is reduced. If the combustion time is less than 3 minutes or the flame front does not reach the mark, the oxygen concentration is increased. This process is repeated, gradually approaching the specified value from both the top and bottom until the concentration difference is less than 0.5%.

[0143] The average of all test data is the final test result. The test results of Comparative Examples 1 and 2 are shown in Table 8. As can be seen from the test results in Table 8, Comparative Example 1 is polyurethane foam without any added flame retardant, and its limiting oxygen index is only 18%; Comparative Example 2 is flame-retardant polyurethane foam prepared with a traditional bromine-antimony synergistic flame retardant consisting of 11.84% decabromodiphenyl ethane and 3.95% antimony trioxide, and its limiting oxygen index is 24.8%.

[0144] Table 8 Results of Limiting Oxygen Index Tests for Comparative Examples 1 and 2

[0145]

[0146] The measured limiting oxygen index (LOI) test results of Example 3 and the theoretical LIOI calculated based on the LIOI of Comparative Examples 1 and 2 are shown in Table 9. As can be seen from the test results in Table 9, when the total addition amount of decabromodiphenyl ethane, brominated cashew phenol 3A (bromine content of 30.03%), and antimony trioxide is 15.79%, the measured LIOI of the resulting polyurethane foam exceeds 22.5%. Therefore, different proportions of decabromodiphenyl ethane and brominated cashew phenol 3A all exhibit a synergistic flame-retardant effect. When the addition amount of decabromodiphenyl ethane is 8.88%, the addition amount of brominated cashew phenol 3A is 2.96%, and the addition amount of antimony trioxide is 3.95%, decabromodiphenyl ethane and brominated cashew phenol 3A exhibit a synergistic flame-retardant effect.

[0147] Table 9. Calculation results of limiting oxygen index test in Example 3.

[0148]

[0149] The measured limiting oxygen index (LOI) test results of Example 4 and the theoretical LIOI calculated based on the LIOI of Comparative Examples 1 and 2 are shown in Table 10. The test results in Table 10 show that when the total addition of decabromodiphenyl ethane, brominated cashew phenol 4A (bromine content of 40.95%), and antimony trioxide is 15.79%, the measured LIOI of the resulting polyurethane foam exceeds 23%. Therefore, different proportions of decabromodiphenyl ethane and brominated cashew phenol 4A all exhibit a synergistic flame-retardant effect. Furthermore, when the addition amounts of decabromodiphenyl ethane are 5.92%, 3.95%, and 2.96%, and the corresponding addition amounts of brominated cashew phenol 4A are 5.92%, 7.89%, and 8.88%, and the addition amount of antimony trioxide is 3.95%, decabromodiphenyl ethane and brominated cashew phenol 4A exhibit a synergistic flame-retardant effect.

[0150] Table 10. Calculation results of limiting oxygen index test in Example 4

[0151]

[0152] The measured limiting oxygen index (LOI) test results of Example 5 and the theoretical LIOI calculated based on the LIOI of Comparative Examples 1 and 2 are shown in Table 11. The test results in Table 11 show that when the total addition of decabromodiphenyl ethane, brominated cashew phenol 5A (bromine content of 54.50%), and antimony trioxide is 15.79%, the measured LIOI of the resulting polyurethane foam exceeds 24%. Therefore, different proportions of decabromodiphenyl ethane and brominated cashew phenol 5A all exhibit a synergistic flame-retardant effect. When the addition amounts of decabromodiphenyl ethane are 5.92% and 2.96%, respectively, the corresponding addition amounts of brominated cashew phenol 5A... When the amounts of antimony trioxide and antimony trioxide were 5.92% and 8.88% respectively, and the addition amount of antimony trioxide was 3.95%, decabromodiphenyl ethane and brominated cashew phenol 5A showed a synergistic effect in flame retardancy. According to the limiting oxygen index test results of Comparative Example 2, when the same 3.95% of antimony trioxide was added, and the addition amount of decabromodiphenyl ethane and brominated cashew phenol 5A was 5.92%, the limiting oxygen index of polyurethane foam was higher than that of Comparative Example 2 with 11.84% decabromodiphenyl ethane.

[0153] Table 11 Calculation results of limiting oxygen index test in Example 5

[0154]

[0155] The experimental results of the limiting oxygen index in Example 6 and the theoretical limiting oxygen index calculated based on the limiting oxygen indices of Comparative Examples 1 and 2 are shown in Table 12. As shown in Table 12, when the total addition of decabromodiphenyl ethane, brominated cashew 6A (bromine content of 62.00%), and antimony trioxide is 15.79%, the measured limiting oxygen index of the polyurethane foam obtained exceeds 24.5%. Therefore, different proportions of decabromodiphenyl ethane and brominated cashew 6A all exhibit a synergistic flame-retardant effect. When the addition amounts of decabromodiphenyl ethane are 7.89%, 5.92%, 3.95%, and 2.96%, the corresponding addition amounts of brominated cashew 6A are 3.95%, 5.92%, 7.89%, and 8.88%, and the addition amount of antimony trioxide is 3.95%, decabromodiphenyl ethane and brominated cashew 6A exhibit a synergistic flame-retardant effect, and the limiting oxygen index is higher than or equal to that of Comparative Example 2 with 11.84% decabromodiphenyl ethane and 3.95% antimony trioxide.

[0156] Table 12 Calculation results of limiting oxygen index test in Example 6

[0157]

[0158] In summary, this invention provides a flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material. Decabromodiphenyl ethane, different proportions of synthetic brominated cashew phenols 3A, 4A, 5A, 6A, and antimony trioxide all exhibit varying degrees of synergistic flame-retardant effects. A partial blending ratio of decabromodiphenyl ethane and brominated cashew phenols demonstrates a synergistic flame-retardant effect. Furthermore, when the bromine content of brominated cashew phenols exceeds 50%, the partial blending ratio of decabromodiphenyl ethane and brominated cashew phenols 5A and 6A not only exhibits a synergistic flame-retardant effect but also exceeds the limiting oxygen index of polyurethane foam with the same amount of decabromodiphenyl ethane. This proves that when the bromine content of the brominated cashew phenols synthesized in this invention exceeds 50%, it can partially replace decabromodiphenyl ethane, which will change the limitation that flame-retardant polyurethane compositions are entirely derived from petroleum-based sources.

[0159] This invention uses brominated cashew phenol, made from cashew phenol, as a flame retardant. On the one hand, brominated cashew phenol can replace or partially replace petroleum-based brominated flame retardants such as decabromodiphenyl ethane, changing the limitation that flame-retardant polyurethane compositions are entirely derived from petroleum. Using brominated cashew phenol as a raw material for preparing flame-retardant polyurethane foam has the advantages of safety and environmental protection. On the other hand, brominated cashew phenol is a low-viscosity liquid with good fluidity and convenient addition, thereby ensuring the molding process of polyurethane foam and the overall toughness of the foam.

[0160] This invention provides a flame-retardant polyurethane composition containing decabromodiphenyl ethane, wherein brominated cashew phenol is both an aliphatic bromine derivative flame retardant and an aromatic bromine derivative flame retardant. Decabromodiphenyl ethane, brominated cashew phenol, and flame-retardant synergists together form a synergistic system in the flame-retardant polyurethane composition. Initially, in the early stages of the flame-retardant process, due to the low bond strength and stability of aliphatic bromine derivatives, they are easily decomposed by heat. Therefore, the bromine on the C15 long chain of brominated cashew phenol preferentially exerts its flame-retardant effect, capturing free radicals during material decomposition, thereby delaying or inhibiting the combustion chain reaction. Simultaneously, the released HBr is itself a flame-retardant gas that can coat the surface of the material, acting as a barrier and diluting the oxygen concentration. Subsequently, as the temperature rises, the aromatic bromine derivative continues to exert its flame-retardant effect, releasing HBr gas in the later stages of combustion to block the spread of combustion. Ultimately, the flame-retardant polyurethane composition of this invention possesses two flame-retardant synergistic systems: bromine-bromine synergy and bromine-antimony synergy, which can exert their flame-retardant effect at different stages of combustion, thereby greatly improving the flame-retardant efficiency of polyurethane foam.

[0161] It should be noted that:

[0162] (1) Brominated cashew phenol has a Brinell viscosity of ≤7850 CPS at 25℃, which is a low viscosity characteristic. Therefore, it is easier to add and use in the process of flame retardant polyurethane foaming, which further ensures the molding process of polyurethane foam and the overall toughness of the foam.

[0163] (2) According to the limiting oxygen index test results in Tables 9 to 12, when the mass ratio of decabromodiphenyl ethane to brominated cashew phenol is 1:1, it exhibits excellent synergistic flame retardant effect.

[0164] (3) In addition to antimony trioxide, other types of flame retardant synergists can be used as substitutes, such as antimony oxides like antimony tetroxide and antimony pentoxide, and antimony metal salts like sodium antimonate. In the above embodiments, the mass percentage of antimony trioxide is 3.95%, which is a preferred embodiment. Those skilled in the art can make appropriate adjustments to the type and proportion of flame retardant synergists in the composition formulation according to actual conditions.

[0165] (4) Processing aids can be distilled water, or deionized water, pure water, etc. can be used instead of distilled water.

[0166] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material, characterized in that, Includes the following raw material components: Decabromodiphenyl ethane, brominated cashew phenol, flame retardant synergist, polyether polyol, polymethylene polyphenyl isocyanate, processing aid.

2. The flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material according to claim 1, characterized in that, The raw material components, by weight, are as follows: decabromodiphenyl ethane is 1.5 to 4.5 parts; brominated cashew phenol is 1.5 to 6 parts; wherein, by mass percentage, the raw material components are required to be: decabromodiphenyl ethane is 2.96 to 8.88% and brominated cashew phenol is 2.96 to 11.84%.

3. The flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material according to claim 2, characterized in that, The raw material components, by weight, are: 2 parts of the flame retardant synergist; 20 parts of the polyether polyol; and 22 parts of the polymethylene polyphenyl isocyanate. The processing aid is 0.68 parts.

4. The flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material according to claim 1, characterized in that, The brominated cashew phenol has a bromine content of ≥30%.

5. A flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material according to claim 4, characterized in that, The brominated cashew phenol has a bromine content of 41% to 62%.

6. A flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material according to claim 5, characterized in that, The mass ratio of the decabromodiphenyl ethane to the brominated cashew phenol is 1:

1.

7. A flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material according to any one of claims 1-6, characterized in that, The flame retardant synergist includes antimony oxide or antimony metal salt.

8. A flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material according to any one of claims 1-6, characterized in that, The processing aids, by weight, include: 0.16 parts water-soluble silicone oil, 0.5 parts water, 0.01 parts triethylenediamine, and 0.01 parts dibutyltin dilaurate.

9. A method for preparing a flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material, as described in any one of claims 1-8, characterized in that, Includes the following steps: Step S1. Weigh each raw material component according to its weight parts; Step S2. Mix the decabromodiphenyl ethane, brominated cashew phenol, flame retardant synergist, polyether polyol, and processing aid weighed in step S1 at a certain temperature to obtain the white material; Step S3. The polymethylene polyphenyl isocyanate weighed in step S1 is used as the black material, and the white material obtained in step S2 is mixed with the black material and foamed to obtain the flame-retardant polyurethane composition.

10. A flame-retardant polyurethane composition containing decabromodiphenyl ethane as a raw material according to any one of claims 1-8, or a flame-retardant polyurethane composition containing decabromodiphenyl ethane prepared by the method of claim 9, is used in the preparation of flame-retardant polyurethane foam.

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