Ammonium dihydrocarbylphosphinate salt, its preparation method and applications

Abstract

This application provides ammonium dihydrocarbylphosphinate salt, a method for preparing the same, and its applications. The ammonium dihydrocarbylphosphinate salt is obtained by an alkylation reaction between an alkyl dihydrocarbylphosphinate ester and nitrogen on the non-tertiary amine structure of a nitrogen-containing organic compound. The ammonium dihydrocarbylphosphinate salt according to this application has a low melting point, is easily liquefied, has good compatibility with resins, a fast compatibility rate, and is easy to handle. This overcomes not only the problems of solid amines having high melting points and being difficult to liquefy, and poor compatibility with resin systems, but also problems such as corrosiveness due to dihydrocarbylphosphinic acid or its residues. The ammonium dihydrocarbylphosphinate salt according to this application not only exhibits high flame retardancy efficiency as a flame retardant, but can also effectively maintain the physical properties of polymer materials, particularly the glass transition temperature. The ammonium dihydrocarbylphosphinate salt according to this application is easy to prepare, does not require solvents or catalysts, has excellent atom economy, and is suitable for large-scale production.

Description

[Technical Field]

[0001] This application belongs to the field of flame-retardant polymer materials and relates to ammonium dihydrocarbylphosphinate salt, its preparation method, and applications. [Background technology]

[0002] Polymeric materials are widely used in all sectors of the national economy, but many of them are flammable. To reduce fire hazards caused by these materials, it is usually necessary to meet flame-retardant requirements through flame-retardant modification. The simplest method of flame-retardant modification is the use of flame retardants.

[0003] In recent years, phosphorus-based flame retardants have been rapidly developed due to their high flame retardancy efficiency and low smoke and toxicity from combustion products, with dihydrocarbylphosphinic acid and its salts being particularly widely used.

[0004] CN110945047A discloses the reaction product of diethylphosphinic acid and epoxy, and its flame retardant application in polyurethane foam, but it is a monohydroxy group-containing flame retardant that reduces the degree of crosslinking of polyurethane and consumes expensive isocyanates. WO2021074684 discloses the use of diethylphosphinic acid or its products with epoxy resins for flame retardation of epoxy resins, but the reaction of diethylphosphinic acid with epoxy reduces the crosslinking functional groups of the epoxy resin, requiring the use of low-exothermic epoxy resins with three or more functional groups. CN113929967B discloses the neutralization product of dihydrocarbylphosphinic acid and amines and its applications, but this product is solid, has poor compatibility with polymer materials, and has problems with uniform dispersion. EP3470444 discloses a quaternary ammonium salt of dihydrocarbylphosphinic acid for polyurethane flame retardation, but the quaternary ammonium salt lacks reactive functional groups and is prone to precipitation and leaching.

[0005] In summary, dihydrocarbylphosphinic acid is highly acidic and can only be used after neutralization. However, neutralization often reduces the number of functional groups in the neutralizing agent, which is detrimental to the physical properties of flame-retardant materials. Furthermore, conventional solid ammonium dihydrocarbylphosphinate has poor compatibility with polymer materials, and quaternary ammonium dihydrocarbylphosphinate has insufficient reaction activity, among other problems. [Overview of the project]

[0006] The following is a summary of the contents described in detail herein. This summary is not intended to limit the scope of the claims.

[0007] This application aims to provide ammonium dihydrocarbylphosphinate salt, a method for preparing the same, and its applications, in view of the shortcomings of the prior art.

[0008] To achieve the above objective, this application employs the following technical modes.

[0009] In one aspect, the present application provides an ammonium dihydrocarbylphosphinate salt, which is obtained by an alkylation reaction between an alkyl dihydrocarbylphosphinate ester having the structure shown in formula (I) and nitrogen on at least one non-tertiary amine structure of NH3 or a nitrogen-containing organic compound, wherein the alkyl group participating in the alkylation reaction is derived from R1 in the structure shown in formula (I), the nitrogen-containing organic compound is selected from primary amines, secondary amines, and imine compounds, and at least one nitrogen atom among the nitrogen atoms that undergo the alkylation reaction in the ammonium dihydrocarbylphosphinate salt simultaneously has a H atom and one R1 group obtained by the alkylation reaction. [ka]

[0010] R1 is selected from linear alkyl groups having 1 to 18 carbon atoms, branched alkyl groups having 1 to 18 carbon atoms, and cycloalkyl groups having 3 to 18 carbon atoms. R2 and R3 are independently selected from linear alkyl groups having 1 to 18 carbon atoms, branched alkyl groups having 1 to 18 carbon atoms, cycloalkyl groups having 3 to 18 carbon atoms, and aryl groups having 6 to 24 carbon atoms.

[0011] In one embodiment, R1 is selected from one of the following groups: methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl groups.

[0012] In one embodiment, R1 is selected from one of a methyl group, an ethyl group, a propyl group, or a butyl group.

[0013] In one embodiment, R1 is selected from either a methyl group or an ethyl group.

[0014] In one embodiment, R2 and R3 are independently selected from one of the following groups: methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, and phenyl groups.

[0015] In one embodiment, R2 and R3 are independently selected from one of an ethyl group, a propyl group, or a butyl group.

[0016] In one embodiment, R2 and R3 are ethyl groups.

[0017] The alkyl dihydrocarbylphosphinate having the structure shown in formula (I) may be a simple alkyl dihydrocarbylphosphinate, or a mixed alkyl dihydrocarbylphosphinate having different R1, R2, and R3 substituents. For example, the above alkyl dihydrocarbylphosphinate may be methyl diethylphosphinate, ethyl diethylphosphinate, or a mixture thereof.

[0018] In one embodiment, the dihydrocarbylphosphinic acid alkyl ester comprises any one or a combination of two or more of methyl dimethylphosphinate, methyl diethylphosphinate, methyl dipropylphosphinate, methyl ethylpropylphosphinate, methyl diphenylphosphinate, ethyl dimethylphosphinate, ethyl diethylphosphinate, ethyl dipropylphosphinate, ethyl ethylpropylphosphinate, propyl dimethylphosphinate, propyl diethylphosphinate, propyl dipropylphosphinate, propyl ethylpropylphosphinate, methyl methylphenylphosphinate, and methyl diphenylphosphinate.

[0019] The nitrogen-containing organic compound is selected from primary amines, secondary amines, and imines. In the present application, a primary amine is a derivative in which one hydrogen atom of an NH3 molecule is substituted with a (substituted) hydrocarbon group, a secondary amine is a derivative in which two hydrogen atoms of an NH3 molecule are substituted with (substituted) hydrocarbon groups, and an imine is structurally equivalent to a product obtained by condensing ammonia or a primary amine with an aldehyde or a ketone, and has an amine represented by the following formula (II).

Chemical Formula

[0020] R4 and R5 are each independently selected from hydrogen, a substituted or unsubstituted alkyl group, and a substituted or unsubstituted aryl group.

[0021] In the structures of the above-mentioned primary amines, secondary amines and imines, a plurality of amino groups and / or imino groups and / or -C=NH groups can be simultaneously contained in the same molecule. For example, a primary amine can simultaneously contain two amino groups, or one amino group and one imino group, or one amino group and one -C=NH group. When a plurality of amino groups, imino groups and / or -C=NH groups are present in the structure of a primary amine, secondary amine or imine, the dihydrocarbylphosphinic acid ammonium salt formed when at least one nitrogen atom thereof participates in an alkylation reaction with an alkyl dihydrocarbylphosphinate also falls within the scope of the present application. In the present application, typical nitrogen-containing organic compounds include any one or a combination of two or more of methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, dodecylamine, octadecylamine, cyclohexylamine, diethylamine, methylpropylamine, ethylenediamine, propanediamine, butanediamine, pentanediamine, hexanediamine, heptanediamine, octanediamine, 1,4-cyclohexanediamine, diethanolamine, m-phenylenediamine, p-phenylenediamine, piperazine, 2-methylpiperazine, 2-methylimidazole, tetraethylenepentamine, triethylenetetramine, aniline, N-methylaniline, 4-methylaniline, diaminodiphenylmethane, 2,2-bis(4-aminophenyl)propane, diaminodiphenylsulfone, diaminobenzophenone, cyanamide, melamine and dicyandiamide.

[0022] In one embodiment, the nitrogen-containing organic compound is a primary amine compound.

[0023] In the ammonium dihydrocarbylphosphinate salt, at least one nitrogen atom has a hydrogen atom among the nitrogen atoms that underwent the alkylation reaction. After the reaction between the alkyl dihydrocarbylphosphinate ester and the nitrogen-containing organic compound is complete, at least one hydrogen atom remains on at least one nitrogen atom that participated in the alkylation reaction in the organic nitrogen portion of the obtained ammonium dihydrocarbylphosphinate salt.

[0024] In one embodiment, the ammonium dihydrocarbylphosphinate salt has one of the following structures: [ka] [ka]

[0025] In equations (III) through (XVIII) above, R1, R2, and R3 have the same definitions as R1, R2, and R3 in equation (I).

[0026] In one embodiment, in formulas (III) to (XVIII) above, R1 is selected from alkyl groups having 1 to 6 carbon atoms, and R2 and R3 are independently selected from linear or branched alkyl groups having 1 to 18 carbon atoms, or from aryl groups having 6 to 24 carbon atoms.

[0027] In one embodiment, R1 is independently selected from a methyl group, an ethyl group, a propyl group, an isopropyl group, and a butyl group, and R2 and R3 are independently selected from a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and a phenyl group.

[0028] In one embodiment, R1 is selected from a methyl group, an ethyl group, and a propyl group, and R2 and R3 are independently selected from an ethyl group, a propyl group, an isopropyl group, and a butyl group.

[0029] In one embodiment, R1 is selected from a methyl group, an ethyl group, and a propyl group, and R2 and R3 are ethyl groups.

[0030] In another aspect, the present application provides a method for preparing the above-mentioned ammonium dihydrocarbylphosphinate salt, the preparation method comprising the step of an alkyl dihydrocarbylphosphinate ester undergoing an alkylation reaction with nitrogen on at least one non-tertiary amine structure of NH3 or a nitrogen-containing organic compound to obtain the ammonium dihydrocarbylphosphinate salt.

[0031] When a nitrogen-containing organic compound has multiple nitrogen atoms, one or more of them can participate in the alkylation reaction, but at least one nitrogen atom will still have at least one hydrogen atom after the alkylation reaction. For example, the nitrogen-containing organic compounds used in this application may include primary amines, secondary amines, and imines having a tertiary amine structure. In this case, the nitrogen atoms on the tertiary amine structure can also be alkylated by dihydrocarbylphosphinate alkyl esters, but at least one of the nitrogen atoms participating in the alkylation reaction of the primary amine, secondary amine, and imine will still have at least one hydrogen atom.

[0032] Typical alkyl dihydrocarbyl phosphinates include one or more combinations of methyl dimethylphosphinate, methyl diethylphosphinate, methyl dipropylphosphinate, methyl ethyl propylphosphinate, methyl diphenylphosphinate, ethyl dimethylphosphinate, ethyl diethylphosphinate, ethyl dipropylphosphinate, ethyl propylphosphinate, propyl dimethylphosphinate, propyl diethylphosphinate, propyl dipropylphosphinate, propyl ethylpropylphosphinate, methylphenylphosphinate, and methyl diphenylphosphinate.

[0033] Optionally, the nitrogen-containing organic compound includes one or more combinations of methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, dodecylamine, octadecylamine, cyclohexylamine, diethylamine, methylpropylamine, ethylenediamine, propanediamine, butanediamine, pentanediamine, hexanediamine, heptanediamine, octanediamine, 1,4-cyclohexanediamine, diethanolamine, m-phenylenediamine, p-phenylenediamine, piperazine, 2-methylpiperazine, 2-methylimidazole, tetraethylenepentamine, triethylenetetramine, aniline, N-methylaniline, 4-methylaniline, diaminodiphenylmethane, 2,2-bis(4-aminophenyl)propane, diaminodiphenylsulfone, diaminobenzophenone, cyanamide, melamine, and dicyandiamide.

[0034] In this application, the molar reaction ratio between the nitrogen-containing organic compound and the dihydrocarbylphosphinate alkyl ester is determined by the total amount of nitrogen in the nitrogen-containing organic compound.

[0035] In one embodiment, the molar ratio of the total number of moles of nitrogen in the nitrogen-containing organic compound to the alkyl dihydrocarbylphosphinate is 10 / 1 to 1 / 10, for example, 10 / 1, 9 / 1, 8 / 1, 7 / 1, 6 / 1, 5 / 1, 4 / 1, 3 / 1, 2 / 1, 1 / 1, 1 / 2, 1 / 3, 1 / 4, 1 / 5, 1 / 6, 1 / 7, 1 / 8, 1 / 9, or 1 / 10. If the molar ratio is too low, the resulting product will not be sufficiently flame-retardant, and if the molar ratio is too high, it will be necessary to recover excess alkyl dihydrocarbylphosphinate, which will reduce economic efficiency.

[0036] In one embodiment, the molar ratio of the total number of moles of nitrogen in the nitrogen-containing organic compound to the alkyl dihydrocarbylphosphinate is 6 / 1 to 1 / 6, and can be, for example, 5 / 1 to 1 / 6, 4 / 1 to 1 / 6, 3 / 1 to 1 / 6, 2 / 1 to 1 / 6, 1 / 1 to 1 / 6, 1 / 1 to 1 / 5, 1 / 1 to 1 / 4, 1 / 1 to 1 / 3, 1 / 1 to 1 / 2.5, or 1 / 1 to 1 / 2.

[0037] In one embodiment, the reaction temperature of the alkylation reaction is 0°C to 250°C, for example, 0°C, 10°C, 50°C, 80°C, 100°C, 150°C, 180°C, 200°C, 220°C, and 250°C.

[0038] In one embodiment, the reaction time for the alkylation reaction is 0.1 to 30 hours, for example, 0.1 hours, 3 hours, 5 hours, 8 hours, 10 hours, 13 hours, 15 hours, 18 hours, 20 hours, 23 hours, 25 hours, 28 hours, and 30 hours.

[0039] In this application, the alkylation reaction can be carried out under atmospheric pressure, negative pressure, or positive pressure.

[0040] When a nitrogen-containing organic compound contains two or more reactive nitrogen atoms, the product may be one in which all or some of the nitrogen atoms are alkylated, or a mixture thereof. For example, after the reaction of diaminodiphenylmethane and methyl diethylphosphinate, the resulting products may have the structures shown in structural formulas (III) and (IV), respectively, or a mixture thereof.

[0041] In another aspect, this application provides a flame-retardant polymer material comprising a flame retardant and a polymer material, wherein the flame retardant comprises the above-mentioned ammonium dihydrocarbylphosphinate salt.

[0042] In one embodiment, the flame-retardant polymer material comprises 0.1 wt% to 50 wt% of a flame retardant and 50 wt% to 99.9 wt% of a polymer material.

[0043] In this application, the mass fraction content of the flame retardant in the flame-retardant polymer material is independently selected from a range defined by any one or any two of the following values: 0.1%, 0.2%, 0.5%, 0.8%, 1%, 1.2%, 1.5%, 2%, 2.2%, 2.5%, 3%, 3.5%, 4%, 5%, 6%, 8%, 10%, 15%, 20%, 30%, 40%, and 50%.

[0044] In one embodiment, the flame-retardant polymer material further includes functional additives.

[0045] In one embodiment, the functional additive is selected from at least one of the following: reinforcing agents, anti-dropping agents, stabilizers, pigments, dyes, char-forming catalysts, dispersants, nucleating agents, inorganic fillers, organic fillers, and antioxidants.

[0046] In one embodiment, the reinforcing agent is selected from glass fibers.

[0047] In one embodiment, the drip-preventing agent is selected from Teflon.

[0048] In one embodiment, the inorganic filler is selected from at least one of silicon dioxide, mica, calcium carbonate, aluminum oxide, aluminum nitride, talc, calcium oxide, calcium silicate, glass fiber powder, and silica.

[0049] In one embodiment, the organic filler is selected from at least one of polytetrafluoroethylene powder, polyphenylene sulfide powder, and polyethersulfone powder.

[0050] In one embodiment, the functional additive is present in the flame-retardant polymer material in a mass fraction of 5% to 40%, for example, 5%, 8%, 10%, 15%, 18%, 20%, 25%, 28%, 30%, 33%, 35%, 38%, and 40%.

[0051] In one embodiment, the flame-retardant polymer material further includes a flame retardant Q.

[0052] In one embodiment, the flame retardant Q is selected from at least one of phosphorus-based flame retardants, nitrogen-based flame retardants, and boron-based flame retardants.

[0053] In one embodiment, the phosphorus-based flame retardant is selected from at least one of bisphosphate esters, phosphazenes, dihydrocarbyl phosphinates, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide derivatives (e.g., 6H-dibenzo[c,e][1,2]oxyphosphoglycerate, 6,6'-(1,2-ethanediyl)bis-6,6'-dioxide, HTP-6123 manufactured by Guizhou Yuanyi Group), and phosphine oxide compounds.

[0054] In one embodiment, the bisphosphate ester is selected from at least one of bisphenol A bis(diphenyl phosphate), resorcinol bis(diphenyl phosphate), and 1,3-phenylene bis(2,6-dimethylphenyl phosphate) (CAS number: 139189-30-3, Phosphoric acid, 1,3-phenylene tetrakis(2,6-dimethylphenyl)ester).

[0055] In one embodiment, the phosphazene flame retardant is selected from at least one of hexafenoxycyclotriphosphazene, cyanophenoxyphosphazene (e.g., FP-300 manufactured by Fushimi Pharmaceutical Co., Ltd. in Japan), allylcyclophosphazene (e.g., SPV-100 manufactured by Nippon Otsuka Co., Ltd.), and cyclic biphenyloxyphosphazene (e.g., BP-PZ manufactured by Nippon Otsuka Co., Ltd.).

[0056] In one embodiment, the dihydrocarbyl phosphinate is selected from at least one of aluminum diethylphosphinate, aluminum diisobutylphosphinate, aluminum dipropylphosphinate, and zinc diethylphosphinate.

[0057] In one embodiment, the 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide derivative is selected from at least one of 6H-dibenzo[c,e][1,2]oxaphosphinin-6,6'-(1,4-ethanediyl)bis-6,6'-dioxide and 6H-dibenzo[c,e][1,2]oxaphosphinin-6,6'-(1,4-phenylethanediyl)bis-6,6'-dioxide.

[0058] In one embodiment, the phosphine oxide compound is p-xylylenebis(diphenylphosphine oxide) (e.g., PQ-60 manufactured by Shinichi Chemical Co., Ltd.).

[0059] In one embodiment, the nitrogen-based flame retardant is selected from at least one of melamine cyanurate, melamine pyrophosphate, and ammonium polyphosphate.

[0060] In one embodiment, the boron-based flame retardant is selected from zinc borate.

[0061] In one embodiment, the flame retardant Q is present in the flame retardant polymer material in a mass fraction of 0.5% to 20%, for example, 0.5%, 0.8%, 1%, 3%, 5%, 8%, 10%, 13%, 15%, 18%, and 20%.

[0062] In one embodiment, the polymer material is selected from thermoplastic polymer resins or thermosetting resins.

[0063] In one embodiment, the thermoplastic polymer resin is selected from at least one of polybutadiene, polyamide, polyester, polyphenylene ether, acrylonitrile-butadiene-styrene copolymer, polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyimide, polyphenylene sulfide, and polyether ether ketone.

[0064] In one embodiment, the thermosetting resin is selected from at least one of vinyl polyphenylene ether resin, epoxy resin, cyanate ester resin, BT resin, bismaleimide resin, phenol resin, polyurethane resin, thermosetting polyimide, unsaturated polyester resin, vinyl ester resin, benzoxazine resin, arylacetylene resin, and furan resin.

[0065] In one embodiment, the thermosetting resin is at least one of vinyl polyphenylene ether resin, epoxy resin, cyanate ester resin, BT resin, bismaleimide resin, and thermosetting polyimide.

[0066] In one embodiment, the thermosetting resin is an epoxy resin.

[0067] In one embodiment, the epoxy resin is selected from at least one of bisphenol A type epoxy resin, bisphenol F type epoxy resin, dicyclopentadiene type epoxy resin, biphenyl type epoxy resin, and naphthol type epoxy resin.

[0068] The epoxy resins relating to this application include, but are not limited to, epoxy resins currently on the market.

[0069] In one embodiment, the flame-retardant polymer material according to this application is a flame-retardant epoxy resin material, the flame-retardant epoxy resin material comprises a flame retardant and an epoxy resin, the flame retardant comprises the above-mentioned ammonium dihydrocarbylphosphinate salt.

[0070] In one embodiment, the flame-retardant epoxy resin material comprises 0.1 wt% to 18 wt% of ammonium dihydrocarbylphosphinate salt and 82 wt% to 99.9 wt% of epoxy resin.

[0071] In one embodiment, the content of the flame retardant having the structure of formula (I) in the flame retardant material is within the range defined by any two of the following values ​​by weight: 0.1%, 0.2%, 0.5%, 0.8%, 1%, 1.2%, 1.5%, 2%, 2.2%, 2.5%, 3%, 3.5%, 4%, 5%, 6%, 8%, 10%, 15%, and 18%.

[0072] In one embodiment, the flame-retardant epoxy resin material further includes a functional additive.

[0073] In one embodiment, the functional additive is selected from at least one of the following: reinforcing agents, anti-dropping agents, stabilizers, pigments, dyes, carbonization accelerators, dispersants, nucleating agents, inorganic fillers, organic fillers, and antioxidants.

[0074] In one embodiment, the reinforcing agent is selected from glass fibers.

[0075] In one embodiment, the drip-preventing agent is selected from Teflon.

[0076] In one embodiment, the inorganic filler is selected from at least one of silicon dioxide, mica, calcium carbonate, aluminum oxide, aluminum nitride, talc, calcium oxide, calcium silicate, glass fiber powder, and silica.

[0077] In one embodiment, the organic filler is selected from at least one of polytetrafluoroethylene powder, polyphenylene sulfide powder, and polyethersulfone powder.

[0078] In one embodiment, the mass fraction content of the functional additive in the flame-retardant epoxy resin material is 5% to 40%, for example, 5%, 8%, 10%, 15%, 18%, 20%, 25%, 28%, 30%, 33%, 35%, 38%, and 40%.

[0079] The ammonium dihydrocarbylphosphinate salt prepared in this application is easy to prepare and suitable for large-scale industrial production. When applied to epoxy resins, it exhibits high flame retardancy and effectively maintains the physical properties of the epoxy resin.

[0080] This application has the following advantages compared to the prior art.

[0081] The ammonium dihydrocarbylphosphinate salt according to this application has a lower melting point, is easier to liquefy, has good compatibility with resins, a faster compatibility rate, and is easier to handle compared to the solid amines prepared therefrom. This overcomes not only the problems of solid amines, such as their high melting points, difficulty in liquefaction, and poor compatibility with resin systems, but also problems such as the corrosiveness of dihydrocarbylphosphinate or its residues.

[0082] The ammonium dihydrocarbylphosphinate salt relating to this application not only exhibits high flame retardancy efficiency as a flame retardant, but can also effectively maintain the physical properties of polymer materials, particularly the glass transition temperature.

[0083] The ammonium dihydrocarbylphosphinate salt described in this application is easy to prepare, requires no solvents or catalysts, involves a 1+1=2 reaction, has excellent atom economy, and is suitable for large-scale production.

[0084] By reading the drawings and detailed explanations, one can understand other aspects of the situation. [Brief explanation of the drawing]

[0085] [Figure 1] This is the proton nuclear magnetic resonance spectrum of DDM-MDP-1-2. [Figure 2]This is the proton nuclear magnetic resonance spectrum of melamine-MDP-1-3. [Figure 3] This is the proton nuclear magnetic resonance spectrum of TEPA-MDP-1-5. [Modes for carrying out the invention]

[0086] The drawings are intended to illustrate the technical modes of this specification and constitute part of the specification. The drawings, together with the embodiments of this application, are intended to illustrate the technical modes of this specification and do not limit the technical modes of this specification.

[0087] The technical modes of this application will be further illustrated by the following specific embodiments. Those skilled in the art should understand that these embodiments are for the purpose of understanding this application and are not intended to limit it.

[0088] The raw materials used in the examples are as follows:

[0089] Melamine: Sinopharm Group Chemical Reagents Co., Ltd. Dicyandiamide (DICY): Shanghai Aladdin Biochemical Technology Co., Ltd. Diaminodiphenylmethane (DDM): Shanghai Aladdin Biochemical Technology Co., Ltd. Tetraethylenepentamine (TEPA): Shanghai Macklin Biochemical Technology Co., Ltd. Methyl diethylphosphinate (MDP): Jiangsu Liside New Materials Co., Ltd. E44 type epoxy resin (DGEBA): Baling Petroleum & Chemical Co., Ltd. Phenolic epoxy resin SQPN-O48(F48): Shandong Shengquan Chemical Co., Ltd. 2-Methylimidazole: Sun Chemical Technology (Shanghai) Co., Ltd. N,N-dimethylformamide (DMF): Shanghai Aladdin Biochemical Technology Co., Ltd. Combustion test standard: GB / T24082008

[0090] Example 1: Preparation of a product obtained by reacting melamine with methyl diethylphosphinate in a molar ratio of 1 / 4. Melamine and methyl diethylphosphinate are reacted in a molar ratio of 1:4, and the specific reaction procedure is as follows.

[0091] 2 g (0.016 mol) of melamine (melting point 354°C) and 13.9 g (0.102 mol) of methyl diethylphosphinate were mixed and reacted at 200°C for 6 hours. Excess methyl diethylphosphinate was removed by vacuum distillation, and after vacuum drying at 160°C, 10.5 g (98.9%) of a yellow viscous liquid was obtained. This is denoted as melamine-MDP-1-4. DMSO-d6 was used as the solvent. 1 The 1H NMR spectrum shows 2.6–3.6 ppm (N-CH3, 12H), 1.3–2.0 ppm (-CH2CH3, 16H), and 0.8–1.2 ppm (-CH2CH3, 24H), and it has the following structure. [ka]

[0092] Example 2 Preparation of a product obtained by reacting melamine with methyl diethylphosphinate in a molar ratio of 1 / 3 Melamine and methyl diethylphosphinate are reacted in a molar ratio of 1:3, and the specific reaction procedure is as follows.

[0093] 10 g (0.08 mol) of melamine (melting point 354°C) and 32.35 g (0.24 mol) of methyl diethylphosphinate were mixed and reacted at 200°C for 6 hours to obtain 36 g (85.0%, transfer loss) of a pale yellow liquid. This is denoted as melamine-MDP-1-3. Figure 2 shows the proton nuclear magnetic resonance spectrum. DMSO-d6 was used as the solvent. 1 The 1H NMR spectrum shows 2.6–3.6 ppm (N-CH3, 9H), 1.3–2.0 ppm (-CH2CH3, 12H), and 0.8–1.2 ppm (-CH2CH3, 18H), and it has the following structure. [ka]

[0094] Example 3 Preparation of a product obtained by reacting dicyandiamide with methyl diethylphosphinate in a molar ratio of 1 / 2 The reaction is carried out by reacting dicyandiamide with methyl diethylphosphinate in a molar ratio of 1:2, and the specific reaction procedure is as follows.

[0095] 5 g (0.06 mol) of dicyandiamide (209.5°C) and 17.8 g (0.13 mol) of methyl diethylphosphinate were mixed and reacted at 180°C to 190°C for 4 hours. After vacuum drying at 160°C, 18.3 g (86.4%, transfer loss) of a yellow transparent liquid was obtained. This was denoted as DICY-MDP-1-2. DMSO-d6 was used as the solvent. 1 The 1H NMR spectrum shows 2.6–3.7 ppm (N-CH3, 6H), 1.3–1.5 ppm (-CH2CH3, 8H), and 0.8–1.1 ppm (-CH2CH3, 12H), and it has the following structure. [ka] mixture

[0096] Example 4 Preparation of a product obtained by reacting dicyandiamide with methyl diethylphosphinate in a molar ratio of 1 / 3. The reaction is carried out by reacting dicyandiamide with methyl diethylphosphinate in a molar ratio of 1:3, and the specific reaction procedure is as follows.

[0097] 5 g (0.06 mol) of dicyandiamide (209.5°C) and 26.7 g (0.2 mol) of methyl diethylphosphinate were mixed and reacted at 190°C for 6 hours. After vacuum drying at 160°C, 27.1 g (92.6%, transfer loss) of a yellow transparent liquid was obtained. This was denoted as DICY-MDP-1-3. DMSO-d6 was used as the solvent. 1 The 1H NMR spectrum shows 2.6–3.7 ppm (N-CH3, 9H), 1.3–1.5 ppm (-CH2CH3, 12H), and 0.8–1.1 ppm (-CH2CH3, 18H), and it has the following structure. [ka]

[0098] Example 5 Preparation of a product obtained by reacting diaminodiphenylmethane and methyl diethylphosphinate in a molar ratio of 1 / 2. 4,4-diaminodiphenylmethane and methyl diethylphosphinate are reacted in a molar ratio of 1:2, and the specific reaction procedure is as follows.

[0099] 10 g (0.05 mol) of 4,4-diaminodiphenylmethane (melting point 89°C~91°C) and 13.31 g (0.10 mol) of methyl diethylphosphinate were mixed and heated to 160°C for approximately 1.5 hours to obtain 22.84 g (98.0%) of a wine-red liquid. This is denoted as DDM-MDP-1-2. Figure 1 shows the proton nuclear magnetic resonance spectrum. DMSO-d6 was used as the solvent. 1 The 1H NMR spectrum shows 6.3–7.2 ppm (Ph-H, NH, 12H), 3.6 ppm (Ph-CH2-Ph, 2H), 2.8–3.0 ppm (N-CH3, 6H), 1.7 ppm (-CH2CH3, 8H), and 1.2 ppm (-CH2CH3, 12H), and it has the following structure. [ka]

[0100] Example 6 Preparation of a product obtained by reacting diaminodiphenylmethane and ethyl diethylphosphinate in a molar ratio of 1 / 2. Preparation of ethyl diethylphosphinate: 100 g (0.6 mol) of triethyl orthoacetate and 75.2 g (0.6 mol) of diethylphosphinic acid were mixed and reacted at 100°C to 110°C for 20 hours. After removing by-products by distillation at 100°C, 88 g (97.8%) of ethyl diethylphosphinate (EDP) was obtained using CDCl3 as the solvent. 1 The 1H NMR spectrum shows 3.9 ppm (PO-CH2CH3, 2H), 1.6 ppm (-CH2CH3, 4H), 1.2 ppm (PO-CH2CH3, 3H), and 1.1 ppm (-CH2CH3, 6H), and it has the following structure. [ka]

[0101] 4,4-diaminodiphenylmethane and ethyl diethylphosphinate were reacted in a molar ratio of 1:2. The specific reaction procedure was as follows: 10 g (0.05 mol) of 4,4-diaminodiphenylmethane (melting point 89°C~91°C) and 14.82 g (0.10 mol) of ethyl diethylphosphinate were mixed and heated to 200°C for approximately 3 hours to obtain 23.98 g (97.0%) of a wine-red liquid. This was denoted as DDM-EDP-1-2. DMSO-d6 was used as the solvent. 1 The 1H NMR spectrum shows 6.3-7.2 ppm (Ph-H, 8H), 3.6 ppm (Ph-CH2-Ph, 2H), 2.8-3.4 ppm (N-CH2CH3, 4H), 1.7 ppm (-CH2CH3, 8H), and 1.2 ppm (-CH2CH3, N-CH2CH3, 18H), and it has the following structure. [ka]

[0102] Example 7 Preparation of a product obtained by reacting tetraethylenepentamine with methyl diethylphosphinate in a molar ratio of 1 / 5. Tetraethylenepentamine and methyl diethylphosphinate are reacted in a molar ratio of 1:5, and the specific reaction procedure is as follows.

[0103] 5 g (0.026 mol) of tetraethylenepentamine (melting point -40°C) and 17.4 g (0.128 mol) of methyl diethylphosphinate were mixed and reacted at 150°C for 1 hour. After vacuum drying at 160°C, 20.28 g (91.9%, transfer loss) of a yellow transparent liquid was obtained. This is denoted as TEPA-MDP-1-5. Figure 3 shows the proton nuclear magnetic resonance spectrum. DMSO-d6 was used as the solvent. 1The 1H NMR spectrum shows 2.0–4.0 ppm (N-CH3, -CH2CH2-, 31H), 1.3–1.5 ppm (-CH2CH3, 20H), and 0.8–1.1 ppm (-CH2CH3, 30H), and it has the following structure. [ka]

[0104] Example 8 79.6 parts of epoxy resin DGEBA were heated to 80°C and softened sufficiently. Then, 17.4 parts of 4,4-diaminodiphenylmethane (DDM) were added and the mixture was stirred rapidly to promote the dissolution of the DDM. After most of the DDM had dissolved, 3 parts of melamine-MDP-1-4 (prepared in Example 1) were added and the mixture was stirred for another minute to form a homogeneous mixture. While still hot, the mixture was poured into a mold preheated to 80°C, left to stand for 10 minutes, then heated to 120°C for 2 hours for pre-curing, and then heated again to 170°C for 4 hours for curing. The mixture was allowed to cool to room temperature by natural cooling to obtain an EP / melamine-MDP-1-4 composite material with an additive amount of 3 wt%. The sample had a thickness of 3.2 mm, reached the UL94 V0 level, and had a Tg of 151°C. Table 1 shows the results.

[0105] Example 9 80.4 parts of epoxy resin DGEBA were heated to 80°C and softened sufficiently. Then, 17.6 parts of 4,4-diaminodiphenylmethane (DDM) were added and the mixture was stirred rapidly to promote the dissolution of the DDM. After most of the DDM had dissolved, 2 parts of melamine-MDP-1-4 (prepared in Example 1) were added and the mixture was stirred for another minute to form a homogeneous mixture. While still hot, the mixture was poured into a mold preheated to 80°C, left to stand for 10 minutes, then heated to 120°C for 2 hours for pre-curing, and then heated again to 170°C for 4 hours for curing. The mixture was allowed to cool to room temperature by natural cooling to obtain an EP / melamine-MDP-1-4 composite material with an additive content of 2 wt%. The sample had a thickness of 3.2 mm and reached UL94 V1 level. Table 1 shows the results.

[0106] Example 10 79.6 parts of epoxy resin DGEBA were heated to 80°C and softened sufficiently. Then, 17.4 parts of 4,4-diaminodiphenylmethane (DDM) were added and the mixture was stirred rapidly to promote the dissolution of the DDM. After most of the DDM had dissolved, 3 parts of melamine-MDP-1-3 (prepared in Example 2) were added and the mixture was stirred for another minute to form a homogeneous mixture. While still hot, the mixture was poured into a mold preheated to 80°C, left to stand for 10 minutes, then heated to 120°C for 2 hours for pre-curing, and then heated again to 170°C for 4 hours for curing. The mixture was allowed to cool to room temperature by natural cooling to obtain an EP / melamine-MDP-1-3 composite material with an additive amount of 3 wt%. The sample had a thickness of 3.2 mm, reached the UL94 V0 level, and had a Tg of 150°C. Table 1 shows the results.

[0107] Example 11 80.4 parts of epoxy resin DGEBA were heated to 80°C and softened sufficiently. Then, 17.6 parts of 4,4-diaminodiphenylmethane (DDM) were added and the mixture was stirred rapidly to promote the dissolution of the DDM. After most of the DDM had dissolved, 2 parts of melamine-MDP-1-3 (prepared in Example 2) were added and the mixture was stirred for another minute to form a homogeneous mixture. While still hot, the mixture was poured into a mold preheated to 80°C, left to stand for 10 minutes, then heated to 120°C for 2 hours for pre-curing, and then heated again to 170°C for 4 hours for curing. The mixture was allowed to cool to room temperature by natural cooling to obtain an EP / melamine-MDP-1-3 composite material with an additive content of 2 wt%. The sample had a thickness of 3.2 mm and reached UL94 V1 level. Table 1 shows the results.

[0108] Example 12 79.6 parts of epoxy resin DGEBA were heated to 80°C and softened sufficiently. Then, 17.4 parts of 4,4-diaminodiphenylmethane (DDM) were added and the mixture was stirred rapidly to promote the dissolution of the DDM. After most of the DDM had dissolved, 3 parts of DICY-MDP-1-2 (prepared in Example 3) were added and the mixture was stirred for another minute to form a homogeneous mixture. While still hot, the mixture was poured into a mold preheated to 80°C, left to stand for 10 minutes, then heated to 120°C for 2 hours for pre-curing, and then heated again to 170°C for 4 hours for curing. The mixture was allowed to cool to room temperature by natural cooling to obtain an EP / DICY-MDP-1-2 composite material with an additive content of 3 wt%. The sample had a thickness of 3.2 mm, reached the UL94 V0 level, and had a Tg of 147°C. Table 1 shows the results.

[0109] Example 13 80.4 parts of epoxy resin DGEBA were heated to 80°C and softened sufficiently. Then, 17.6 parts of 4,4-diaminodiphenylmethane (DDM) were added and the mixture was stirred rapidly to promote the dissolution of the DDM. After most of the DDM had dissolved, 2 parts of DICY-MDP-1-2 (prepared in Example 3) were added and the mixture was stirred for another minute to form a homogeneous mixture. While still hot, the mixture was poured into a mold preheated to 80°C, left to stand for 10 minutes, then heated to 120°C for 2 hours for pre-curing, and then heated again to 170°C for 4 hours for curing. The mixture was allowed to cool to room temperature by natural cooling to obtain an EP / DICY-MDP-1-2 composite material with an additive content of 2 wt%. The sample had a thickness of 3.2 mm and reached UL94 V1 level. Table 1 shows the results.

[0110] Example 14 80.4 parts of epoxy resin DGEBA were heated to 80°C and softened sufficiently. Then, 17.6 parts of 4,4-diaminodiphenylmethane (DDM) were added and the mixture was stirred rapidly to promote the dissolution of the DDM. After most of the DDM had dissolved, 2 parts of DICY-MDP-1-3 (prepared in Example 4) were added and the mixture was stirred for another minute to form a homogeneous mixture. While still hot, the mixture was poured into a mold preheated to 80°C, left to stand for 10 minutes, then heated to 120°C for 2 hours for pre-curing, and then heated again to 170°C for 4 hours for curing. The mixture was allowed to cool to room temperature by natural cooling to obtain an EP / DICY-MDP-1-3 composite material with an additive content of 2 wt%. The sample had a thickness of 3.2 mm, reached the UL94 V0 level, and had a Tg of 153°C. Table 1 shows the results.

[0111] Example 15 81.3 parts of epoxy resin DGEBA were heated to 80°C and softened sufficiently. Then, 17.7 parts of 4,4-diaminodiphenylmethane (DDM) were added and the mixture was stirred rapidly to promote the dissolution of the DDM. After most of the DDM had dissolved, 1 part of DICY-MDP-1-3 (prepared in Example 4) was added and the mixture was stirred for another minute to form a homogeneous mixture. While still hot, the mixture was poured into a mold preheated to 80°C, left to stand for 10 minutes, then heated to 120°C for 2 hours for pre-curing, and then heated again to 170°C for 4 hours for curing. The mixture was allowed to cool to room temperature by natural cooling to obtain an EP / DICY-MDP-1-3 composite material with an additive amount of 1 wt%. The sample had a thickness of 3.2 mm and reached UL94 V1 level. Table 1 shows the results.

[0112] Example 16 78.8 parts of epoxy resin DGEBA were heated to 80°C and softened sufficiently. Then, 17.2 parts of 4,4-diaminodiphenylmethane (DDM) were added and the mixture was stirred rapidly to promote the dissolution of the DDM. After most of the DDM had dissolved, 4 parts of DDM-MDP-1-2 (prepared in Example 5) were added and the mixture was stirred for another minute to form a homogeneous mixture. While still hot, the mixture was poured into a mold preheated to 80°C, left to stand for 10 minutes, then heated to 120°C for 2 hours for pre-curing, and then heated again to 170°C for 4 hours for curing. The mixture was allowed to cool to room temperature by natural cooling to obtain an EP / DDM-MDP-1-2 composite material with an additive content of 4 wt%. The sample had a thickness of 3.2 mm, reached the UL94 V0 level, and had a Tg of 145°C. Table 1 shows the results.

[0113] Example 17 79.6 parts of epoxy resin DGEBA were heated to 80°C and softened sufficiently. Then, 17.4 parts of 4,4-diaminodiphenylmethane (DDM) were added and the mixture was stirred rapidly to promote the dissolution of the DDM. After most of the DDM had dissolved, 3 parts of DDM-MDP-1-2 (prepared in Example 5) were added and the mixture was stirred for another minute to form a homogeneous mixture. While still hot, the mixture was poured into a mold preheated to 80°C, left to stand for 10 minutes, then heated to 120°C for 2 hours for pre-curing, and then heated again to 170°C for 4 hours for curing. The mixture was allowed to cool to room temperature by natural cooling to obtain an EP / DDM-MDP-1-2 composite material with an additive content of 3 wt%. The sample had a thickness of 3.2 mm and reached UL94 V1 level. Table 1 shows the results.

[0114] Example 18 81.0 parts of epoxy resin DGEBA was heated at 80°C to fully soften it, then 15.0 parts of 4,4-diaminodiphenylmethane (DDM) was added, and the mixture was stirred at high speed to promote the dissolution of DDM. After most of the DDM was dissolved, 4 parts of DDM-MDP-1-2 (prepared in Example 5, with part of DDM replaced by 4 functional groups) was added, and the mixture was further stirred for 1 minute to form a uniform mixed solution. While still hot, the mixed solution was poured into a mold preheated to 80°C, allowed to stand for 10 minutes, then heated to 120°C for pre-curing for 2 hours, and then heated again to 170°C for curing for 4 hours. The mixture was naturally cooled to room temperature, and an EP / DDM-MDP-1-2-react-4 composite material with an addition amount of 4wt% was obtained. The sample meets the V0 level of UL94. Soxhlet extraction was performed using dichloromethane, and the extract obtained after 24 hours was 1 H NMR and 31 analyzed by P NMR, no DDM-MDP-1-2 was detected. This indicates that DDM-MDP-1-2 participated in the curing.

[0115] Example 19 80.1 parts of epoxy resin DGEBA was heated at 80°C to fully soften it, then 16.9 parts of 4,4-diaminodiphenylmethane (DDM) was added, and the mixture was stirred at high speed to promote the dissolution of DDM. After most of the DDM was dissolved, 3 parts of DDM-MDP-1-2 (prepared in Example 2, with part of DDM replaced by 2 functional groups) was added, and the mixture was further stirred for 1 minute to form a uniform mixed solution. While still hot, the mixed solution was poured into a mold preheated to 80°C, allowed to stand for 10 minutes, then heated to 120°C for pre-curing for 2 hours, and then heated again to 180°C for curing for 4 hours. The mixture was naturally cooled to room temperature, and an EP / DDM-MDP-1-2-react-2 composite material with an addition amount of 3wt% was obtained. The sample meets the V0 level of UL94, and has a Tg of 150°C. Table 1 shows the results.

[0116] Example 20 78.8 parts of epoxy resin DGEBA were heated to 80°C and softened sufficiently. Then, 17.2 parts of 4,4-diaminodiphenylmethane (DDM) were added and the mixture was stirred rapidly to promote the dissolution of the DDM. After most of the DDM had dissolved, 4 parts of DDM-EDP-1-2 (prepared in Example 6) were added and the mixture was stirred for another minute to form a homogeneous mixture. While still hot, the mixture was poured into a mold preheated to 80°C, left to stand for 10 minutes, then heated to 120°C for 2 hours for pre-curing, and then heated again to 170°C for 4 hours for curing. The mixture was allowed to cool to room temperature by natural cooling to obtain an EP / DDM-EDP-1-2 composite material with an additive content of 4 wt%. The sample had a thickness of 3.2 mm, reached the UL94 V0 level, and had a Tg of 146°C. Table 1 shows the results.

[0117] Example 21 79.6 parts of epoxy resin DGEBA were heated to 80°C and softened sufficiently. Then, 17.2 parts of 4,4-diaminodiphenylmethane (DDM) were added and the mixture was stirred rapidly to promote the dissolution of the DDM. After most of the DDM had dissolved, 3 parts of DDM-EDP-1-2 (prepared in Example 6) were added and the mixture was stirred for another minute to form a homogeneous mixture. While still hot, the mixture was poured into a mold preheated to 80°C, left to stand for 10 minutes, then heated to 120°C for 2 hours for pre-curing, and then heated again to 170°C for 4 hours for curing. The mixture was allowed to cool to room temperature by natural cooling to obtain an EP / DDM-EDP-1-2 composite material with an additive content of 3 wt%. The sample had a thickness of 3.2 mm and reached UL94 V1 level. Table 1 shows the results.

[0118] Example 22 79.6 parts of epoxy resin DGEBA were heated to 80°C and softened sufficiently. Then, 17.4 parts of 4,4-diaminodiphenylmethane (DDM) were added and the mixture was stirred rapidly to promote the dissolution of the DDM. After most of the DDM had dissolved, 3 parts of TEPA-MDP-1-5 (prepared in Example 7) were added and the mixture was stirred for another minute to form a homogeneous mixture. While still hot, the mixture was poured into a mold preheated to 80°C, left to stand for 10 minutes, then heated to 120°C for 2 hours for pre-curing, and then heated again to 170°C for 4 hours for curing. The mixture was allowed to cool to room temperature by natural cooling to obtain an EP / TEPA-MDP-1-5 composite material with an additive amount of 3 wt%. The sample had a thickness of 3.2 mm, reached the UL94 V0 level, and had a Tg of 148°C. Table 1 shows the results.

[0119] Example 23 80.4 parts of epoxy resin DGEBA were heated to 80°C and softened sufficiently. Then, 17.6 parts of 4,4-diaminodiphenylmethane (DDM) were added and the mixture was stirred rapidly to promote the dissolution of the DDM. After most of the DDM had dissolved, 2 parts of TEPA-MDP-1-5 (prepared in Example 7) were added and the mixture was stirred for another minute to form a homogeneous mixture. While still hot, the mixture was poured into a mold preheated to 80°C, left to stand for 10 minutes, then heated to 120°C for 2 hours for pre-curing, and then heated again to 170°C for 4 hours for curing. The mixture was allowed to cool to room temperature by natural cooling to obtain an EP / TEPA-MDP-1-5 composite material with an additive amount of 2 wt%. The sample had a thickness of 3.2 mm and reached UL94 V1 level. Table 1 shows the results.

[0120] Example 24 83.2 parts of F48 epoxy resin, 8.7 parts of dicyandiamide, 0.1 parts of 2-methylimidazole, and 8 parts of DICY-MDP-1-3 (prepared in Example 4) were mixed. An equal mass of N,N-dimethylformamide (DMF) was added to promote dissolution, and the mixture was heated and stirred at 100°C. After forming a homogeneous solution, the DMF was removed in a vacuum oven at 100°C. Finally, the mixture was poured into a mold preheated to 100°C, pre-cured at 130°C for 1 hour, and then cured at 170°C for 4 hours to obtain an EP-F48 / DICY-MDP-1-3 composite material with an 8% additive content. The sample had a thickness of 3.2 mm and reached the UL94 V0 level. Table 1 shows the results.

[0121] Example 25 83.2 parts of F48 epoxy resin, 8.7 parts of dicyandiamide, 0.1 parts of 2-methylimidazole, and 8 parts of TEPA-MDP-1-5 (prepared in Example 7) were mixed. An equal mass of N,N-dimethylformamide (DMF) was added to promote dissolution, and the mixture was heated and stirred at 100°C. After forming a homogeneous solution, the DMF was removed in a vacuum oven at 100°C. Finally, the mixture was poured into a mold preheated to 100°C, pre-cured at 130°C for 1 hour, and then cured at 170°C for 4 hours to obtain an EP-F48 / TEPA-MDP-1-5 composite material with an 8% additive content. The sample had a thickness of 3.2 mm and reached the UL94 V0 level. Table 1 shows the results.

[0122] Example 26 Polypropylene (PP) was dried in a forced-air dryer at 80°C for 4 hours. Then, 80 parts of PP and 20 parts of DICY-MDP-1-3 (prepared in Example 4) were melted in a closed-type kneader at a rotation speed of 50 r / min. The mixture was then processed at a temperature of 200°C for 6 minutes, after which it was removed, cooled, and dried. The mixture was again filled into a mold and preheated in a vulcanizing press at 200°C for 10 minutes, followed by holding pressure at 10 MPa for 5 minutes, and then cold-worked. After cooling, a sample was taken and tested. The sample had a thickness of 3.2 mm and reached the UL94 V0 level.

[0123] Comparative Example 1 4,4-diaminodiphenylmethane and diethylphosphinic acid were reacted in a 1:2 molar ratio. 5.97 g (0.049 mol) of diethylphosphinic acid was gradually added to a total of 5 g (0.025 mol) of 4,4-diaminodiphenylmethane, and the reaction was carried out at 80-100°C. The reaction was considered complete when the 4,4-diaminodiphenylmethane was completely dissolved. 10.4 g (94.8%, transfer loss) of the yellow liquid product DDM-DEP-1-2 was obtained. It slowly crystallized at room temperature, forming a yellowish-green solid. It is extremely hygroscopic in air, making it inconvenient to handle. 。1 The 1H NMR spectrum showed 7.0 ppm (Ph-H, 4H), 6.8 ppm (NH, 6H), 6.7 ppm (Ph-H, 4H), 3.8 ppm (Ph-CH2-Ph, 2H), 1.7 ppm (-CH2CH3, 8H), and 1.2 ppm (-CH2CH3, 12H), and it has the following structure. [ka]

[0124] Comparative Example 2 Melamine and diethylphosphinic acid were reacted in a molar ratio of 1:3. 5 g (0.04 mol) of melamine and 14.51 g (0.12 mol) of diethylphosphinic acid were mixed and reacted at 190-200°C for 2 hours to obtain 17.55 g (89.9%, transfer loss) of melamine-DEP-1-3, a pale yellow paste-like solid. It had extremely poor compatibility with DGEBA, and after curing, most of the melamine-DEP-1-3 remained in the solid state within the EP. 1 The 1H NMR spectrum shows 6.0–11.0 ppm (NH, 9H), 1.3–1.5 ppm (-CH2CH3, 12H), and 0.8–1.1 ppm (-CH2CH3, 18H), and it has the following structure. [ka]

[0125] Comparative Example 3 Dicyandiamide and diethylphosphinic acid were reacted in a 1:2 molar ratio. 5 g (0.06 mol) of dicyandiamide and 14.51 g (0.12 mol) of diethylphosphinic acid were mixed and reacted at 100°C. Alkaline gas in the exhaust gas was detected using pH test paper. NMR results showed that the reaction mixture was a mixture of dicyandiamide, diethylphosphinic acid, and the product DICY-DEP-1-2, accompanied by a large amount of by-products. A simple DICY-DEP-1-2 product was not obtained.

[0126] Comparative Example 4 Dicyandiamide and diethylphosphinic acid were reacted in a 1:2 molar ratio. 5 g (0.06 mol) of dicyandiamide and 14.51 g (0.12 mol) of diethylphosphinic acid were mixed, dissolved in 30 g of water, and then reacted at 70°C for 30 minutes to obtain an aqueous solution of DICY-DEP-1-2. When the water was removed by rotary evaporation at 70°C, the product decomposed. 31 The reappearance of the diethylphosphinic acid peak in the 1P NMR spectrum indicated that diethylphosphinic acid had been regenerated.

[0127] Comparative Example 5 Tetraethylenepentamine and diethylphosphinic acid were reacted in a molar ratio of 1:5. When 5 g (0.026 mol) of tetraethylenepentamine and 15.31 g (0.125 mol) of diethylphosphinic acid were mixed and heated to 100°C, a large amount of alkaline gas was detected in the exhaust gas using pH test paper, so a simple TEPA-DEP-1-5 product could not be obtained.

[0128] Comparative Example 6 82.1 parts of epoxy resin DGEBA were heated to 80°C and softened sufficiently. Then, 17.9 parts of 4,4-diaminodiphenylmethane (DDM) were added, and the mixture was stirred rapidly to promote the dissolution of the DDM. After the DDM was completely dissolved, the mixture was poured while still hot into a mold preheated to 80°C, left to stand for 10 minutes, then heated to 120°C for 2 hours for pre-curing, and then heated again to 170°C for 4 hours for curing. The mixture was allowed to cool to room temperature by natural cooling to obtain a simple EP material. The sample had a thickness of 3.2 mm, reached the UL94 NR level, and had a Tg of 149°C. Table 1 shows the results.

[0129] Comparative Example 7 79.6 parts of epoxy resin DGEBA were heated to 80°C and softened sufficiently. Then, 17.4 parts of 4,4-diaminodiphenylmethane (DDM) were added, and the mixture was stirred rapidly to promote the dissolution of the DDM. After most of the DDM had dissolved, 3 parts of melamine-DEP-1-3 (prepared in Comparative Example 2) were added, and the mixture was stirred for another minute to form a homogeneous mixture. While still hot, the mixture was poured into a mold preheated to 80°C, left to stand for 10 minutes, then heated to 120°C for 2 hours for pre-curing, and then heated again to 170°C for 4 hours for curing. The mixture was allowed to cool to room temperature by natural cooling to obtain an EP / melamine-DEP-1-3 composite material with an additive amount of 3 wt%. The sample had a thickness of 3.2 mm and reached UL94 V1 level. Table 1 shows the results.

[0130] Comparative Example 8 79.6 parts of epoxy resin DGEBA were heated to 80°C and softened sufficiently. Then, 17.4 parts of 4,4-diaminodiphenylmethane (DDM) were added, and the mixture was stirred rapidly to promote the dissolution of the DDM. After most of the DDM had dissolved, 3 parts of DDM-DEP-1-2 (prepared in Comparative Example 1) were added, and the mixture was stirred for another minute to form a homogeneous mixture. While still hot, the mixture was poured into a mold preheated to 80°C, left to stand for 10 minutes, then heated to 120°C for 2 hours for pre-curing, and then heated again to 170°C for 4 hours for curing. The mixture was allowed to cool to room temperature by natural cooling to obtain an EP / DDM-DEP-1-2 composite material with an additive amount of 3 wt%. The sample had a thickness of 3.2 mm, reached the UL94 V0 level, and had a Tg of 153°C. Table 1 shows the results.

[0131] Comparative Example 9 90.4 parts of F48 epoxy resin, 9.5 parts of dicyandiamide, and 0.1 parts of 2-methylimidazole were mixed, and an equal mass of N,N-dimethylformamide (DMF) was added to promote dissolution. The mixture was heated and stirred at 100°C. After forming a homogeneous solution, the DMF was removed in a vacuum oven at 100°C. Finally, the mixture was poured into a mold preheated to 100°C, pre-cured at 130°C for 1 hour, and then cured at 170°C for 4 hours to obtain simple EP-F48. The sample had a thickness of 3.2 mm and reached the UL94 NR level. Table 1 shows the results.

[0132] Comparative Example 10 100 parts of polypropylene (PP) were dried in a forced-air dryer at 80°C for 4 hours. The PP was then melted in a closed-type kneader at a rotation speed of 50 r / min, processed at a temperature of 200°C for 6 minutes, then removed, cooled, and dried. The PP was again filled into a mold, preheated in a vulcanizing press at 200°C for 10 minutes, held under pressure of 10 MPa for 5 minutes, and then cold-worked. After cooling, a sample was taken and tested. The sample had a thickness of 3.2 mm and reached the UL94 NR level.

[0133] In Example 18, a flame retardant prepared using DDM as a raw material was used, and it was used as a reactive additive in place of a portion of the curing agent DDM. Soxhlet extraction was performed on the solidified sample, and the flame retardant DDM-MDP-1-2 was not detected in the extract, indicating that DDM-MDP-1-2 participates in the curing of the epoxy resin and can be used as a reactive flame retardant.

[0134] In Comparative Example 7 and Examples 8-11, flame retardants prepared using melamine as a raw material were used in all cases. However, the flame retardancy of the reaction product of methyl diethylphosphinate and melamine was clearly superior to that of the neutralization product of diethylphosphinic acid and melamine prepared in Comparative Example 2, despite having a lower phosphorus content. This was an unexpected result.

[0135] In Comparative Example 8 and Examples 16, 17, and 19, flame retardants prepared using DDM as a raw material were all employed. The flame retardancy of the flame retardant according to this application is equivalent to the neutralization product of diethylphosphinic acid and DDM prepared in Comparative Example 1, but the latter is prone to hygroscopicity, making it inconvenient for storage and use.

[0136] The results from Examples 12-15, 22, and 23 show that the reaction products of diethylphosphinic acid ester with DICY and TEPA also have very high flame retardancy. In Example 14, V0 was achieved using only 2 parts of the flame retardant according to this application, and even when only 1 part was used (Example 15), the epoxy resin was significantly improved to the V1 level. On the other hand, the neutralization product corresponding to diethylphosphinic acid cannot be obtained because DICY and TEPA undergo acid decomposition reactions during the synthesis process (Comparative Examples 3, 4, and 5), demonstrating the superiority of diethylphosphinic acid ester as a substitute for diethylphosphinic acid.

[0137] A comparison of Comparative Example 9 with Examples 24 and 25 shows that the flame retardant according to this application exhibits good flame retardancy in phenol epoxy resins, and that flame retardancy requirements can be met with an additive amount of less than 10%. Example 26 is an example of applying the flame retardant according to this application to polypropylene (PP). Using a flame retardant prepared from DICY as a raw material, this flame retardant, added at a concentration of 20%, was able to make the PP pass the UL94 test. This indicates that the flame retardant according to this application can be widely applied to polymer materials such as epoxy resins and polyolefins.

[0138] [Table 1(1)] [Table 1(2)] [Table 1(3)]

[0139] This application describes the ammonium dihydrocarbylphosphinate salt, its preparation method, and applications as described by the above-described examples, but declares that this application is not limited to the above-described examples, that is, it does not mean that this application cannot be implemented without relying on the above-described examples. Those skilled in the art should understand that any improvements to this application, equivalent substitutions and additions of auxiliary components to the raw materials used in this application, and selection of specific embodiments are all included within the scope of protection and disclosure of this application.

Claims

1. Ammonium dihydrocarbylphosphinate salt, 【Chemistry 1】 A dihydrocarbylphosphinate alkyl ester having the structure shown in formula (I), and NH ３ Alternatively, it can be obtained by an alkylation reaction with nitrogen on at least one non-tertiary amine structure of a nitrogen-containing organic compound. The alkyl group participating in the alkylation reaction originates from R1 in the structure shown in formula (I), the nitrogen-containing organic compound is selected from primary amines, secondary amines, and imine compounds, and at least one nitrogen atom among the nitrogen atoms that have undergone the alkylation reaction in the ammonium dihydrocarbylphosphinate salt simultaneously has a H atom and one R1 group obtained by the alkylation reaction. R1 is selected from linear alkyl groups having 1 to 18 carbon atoms, branched alkyl groups having 1 to 18 carbon atoms, and cycloalkyl groups having 3 to 18 carbon atoms. R2 and R3 are independently selected from linear alkyl groups having 1 to 18 carbon atoms, branched alkyl groups having 1 to 18 carbon atoms, cycloalkyl groups having 3 to 18 carbon atoms, and aryl groups having 6 to 24 carbon atoms. A dihydrocarbylphosphinate ammonium salt characterized by the following features.

2. R1 is selected from one of the following groups: methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, or decyl. The ammonium dihydrocarbylphosphinate salt according to feature 1.

3. R2 and R3 are independently selected from one of the following groups: methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, or phenyl. The ammonium dihydrocarbylphosphinate salt according to feature 1.

4. R1 is selected from one of the following groups: methyl, ethyl, propyl, or butyl. The ammonium dihydrocarbylphosphinate salt according to feature 1.

5. R1 is selected from either a methyl group or an ethyl group. The ammonium dihydrocarbylphosphinate salt according to feature 1.

6. R2 and R3 are independently selected from one of the following: an ethyl group, a propyl group, or a butyl group. The ammonium dihydrocarbylphosphinate salt according to feature 1.

7. R2 and R3 are ethyl groups. The ammonium dihydrocarbylphosphinate salt according to feature 1.

8. The aforementioned alkyl dihydrocarbylphosphinate includes one or more combinations of methyl dimethylphosphinate, methyl diethylphosphinate, methyl dipropylphosphinate, methyl ethyl propylphosphinate, methyl diphenylphosphinate, ethyl dimethylphosphinate, ethyl diethylphosphinate, ethyl dipropylphosphinate, ethyl propylphosphinate, propyl diethylphosphinate, propyl dipropylphosphinate, propyl ethylpropylphosphinate, methylphenylphosphinate, and methyl diphenylphosphinate. Optionally, the nitrogen-containing organic compound includes one or more combinations of methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, dodecylamine, octadecylamine, cyclohexylamine, diethylamine, methylpropylamine, ethylenediamine, propanediamine, butanediamine, pentanediamine, hexanediamine, heptanediamine, octanediamine, 1,4-cyclohexanediamine, diethanolamine, m-phenylenediamine, p-phenylenediamine, piperazine, 2-methylpiperazine, 2-methylimidazole, tetraethylenepentamine, triethylenetetramine, aniline, N-methylaniline, 4-methylaniline, diaminodiphenylmethane, 2,2-bis(4-aminophenyl)propane, diaminodiphenylsulfone, diaminobenzophenone, cyanamide, melamine, and dicyandiamide. Optionally, the imin is, 【Chemistry 2】 Having the structure shown in formula (II), R4 and R5 are independently selected from hydrogen, substituted or unsubstituted alkyl groups, and substituted or unsubstituted aryl groups. Optionally, the nitrogen-containing organic compound is a primary amine compound. The ammonium dihydrocarbylphosphinate salt according to any one of claims 1 to 7. 【Request Item 9】 【Chemistry 3】 【Chemistry 4】 Having one of the following structures, R1, R2, and R3 have the same definitions as in claim 1. The ammonium dihydrocarbylphosphinate salt according to any one of claims 1 to 8.

10. Alkyl dihydrocarbyl phosphinate esters are NH ３ Alternatively, the process may include carrying out an alkylation reaction with nitrogen on at least one non-tertiary amine structure of a nitrogen-containing organic compound to obtain the ammonium dihydrocarbylphosphinate salt. A method for preparing an ammonium dihydrocarbylphosphinate salt according to any one of claims 1 to 9.

11. The aforementioned alkyl dihydrocarbylphosphinate includes one or a combination of two of the following: methyl dimethylphosphinate, methyl diethylphosphinate, methyl dipropylphosphinate, methyl ethyl propylphosphinate, methyl diphenylphosphinate, ethyl dimethylphosphinate, ethyl diethylphosphinate, ethyl dipropylphosphinate, propyl ethylpropylphosphinate, methylphenylphosphinate, methyl diphenylphosphinate, propyl diethylphosphinate, propyl dipropylphosphinate, propyl ethylpropylphosphinate, methyl methylphenylphosphinate, and methyl diphenylphosphinate. Optionally, the nitrogen-containing organic compound may include one or a combination of two of the following: methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, dodecylamine, octadecylamine, cyclohexylamine, diethylamine, methylpropylamine, ethylenediamine, propanediamine, butanediamine, pentanediamine, hexanediamine, heptanediamine, octanediamine, 1,4-cyclohexanediamine, diethanolamine, m-phenylenediamine, p-phenylenediamine, piperazine, 2-methylpiperazine, 2-methylimidazole, tetraethylenepentamine, triethylenetetramine, aniline, N-methylaniline, 4-methylaniline, diaminodiphenylmethane, 2,2-bis(4-aminophenyl)propane, diaminodiphenylsulfone, diaminobenzophenone, cyanamide, melamine, and dicyandiamide. The preparation method according to feature 10.

12. The molar ratio of the total number of moles of nitrogen in the nitrogen-containing organic compound to the alkyl dihydrocarbylphosphinate is 10 / 1 to 1 / 10. Optionally, the reaction temperature of the alkylation reaction is 0°C to 250°C. Optionally, the reaction time for the alkylation reaction is 0.1 hours to 30 hours. The preparation method according to claim 10 or 11, characterized by the features described herein.

13. The material comprises a flame retardant and a polymer material, wherein the flame retardant comprises an ammonium dihydrocarbylphosphinate salt as described in any one of claims 1 to 9. A flame-retardant polymer material characterized by the following.

14. The flame-retardant polymer material comprises 0.1 to 50 wt% of a flame retardant and 50 wt% to 99.9 wt% of a polymer material. Optionally, the flame-retardant polymer material further includes functional additives. The functional additive is optionally selected from at least one of the following: reinforcing agents, anti-dropping agents, stabilizers, pigments, dyes, carbonization accelerators, dispersants, nucleating agents, inorganic fillers, organic fillers, and antioxidants. The reinforcing agent is optionally selected from glass fibers. The drip-preventing agent is optionally selected from Teflon, The inorganic filler is optionally selected from at least one of silicon dioxide, mica, calcium carbonate, aluminum oxide, aluminum nitride, talc, calcium oxide, calcium silicate, glass fiber powder, and silica. The organic filler is optionally selected from at least one of polytetrafluoroethylene powder, polyphenylene sulfide powder, and polyethersulfone powder. Optionally, the functional additive is present in the flame-retardant polymer material at a mass fraction content of 5% to 40%. Optionally, the flame-retardant polymer material further contains a flame retardant Q. The flame retardant Q is optionally selected from at least one of phosphorus-based flame retardants, nitrogen-based flame retardants, and boron-based flame retardants. The phosphorus-based flame retardant is optionally selected from at least one of bisphosphate esters, phosphazenes, dihydrocarbyl phosphinates, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide derivatives, 6,6'-(1,2-ethanediyl)bis-6,6'-dioxide, HTP-6123, and phosphine oxide compounds. The bisphosphate ester is optionally selected from at least one of bisphenol A bis(diphenyl phosphate), resorcinol bis(diphenyl phosphate), and 1,3-phenylene bis(2,6-dimethylphenyl phosphate). The phosphazene flame retardant is optionally selected from at least one of hexaphenoxycyclotriphosphazene, cyanophenoxyphosphazene, allylcyclophosphazene, and cyclic biphenyloxyphosphazene. The dihydrocarbyl phosphinate is optionally selected from at least one of aluminum diethylphosphinate, aluminum diisobutylphosphinate, aluminum dipropylphosphinate, and zinc diethylphosphinate. The 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide derivative is optionally selected from at least one of 6H-dibenzo[c,e][1,2]oxaphosphinin-6,6'-(1,4-ethanediyl)bis-6,6'-dioxide and 6H-dibenzo[c,e][1,2]oxaphosphinin-6,6'-(1,4-phenylethanediyl)bis-6,6'-dioxide. Optionally, the phosphine oxide compound is p-xylylenebis(diphenylphosphine oxide), The nitrogen-based flame retardant is optionally selected from at least one of melamine cyanurate, melamine pyrophosphate, and ammonium polyphosphate. The boron-based flame retardant may be optionally selected from zinc borate. Optionally, the flame retardant Q is present in the flame retardant polymer material at a mass fraction content of 0.5% to 20%. The polymer material is optionally selected from thermoplastic polymer resins or thermosetting resins. The thermoplastic polymer resin is optionally selected from at least one of polybutadiene, polyamide, polyester, polyphenylene ether, acrylonitrile-butadiene-styrene copolymer, polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyimide, polyphenylene sulfide, and polyether ether ketone. The thermosetting resin is optionally selected from at least one of vinyl polyphenylene ether resin, epoxy resin, cyanate ester resin, BT resin, bismaleimide resin, phenol resin, polyurethane resin, thermosetting polyimide, unsaturated polyester resin, vinyl ester resin, benzoxazine resin, arylacetylene resin, and furan resin. Optionally, the thermosetting resin is at least one of vinyl polyphenylene ether resin, epoxy resin, cyanate ester resin, BT resin, bismaleimide resin, and thermosetting polyimide. Optionally, the thermosetting resin is an epoxy resin. The epoxy resin is optionally selected from at least one of bisphenol A type epoxy resin, bisphenol F type epoxy resin, dicyclopentadiene type epoxy resin, biphenyl type epoxy resin, and naphthol type epoxy resin. The flame-retardant polymer material according to feature 13.

15. The flame-retardant polymer material is a flame-retardant epoxy resin material, the flame-retardant epoxy resin material comprises a flame retardant and an epoxy resin, the flame retardant comprises an ammonium dihydrocarbylphosphinate salt according to any one of claims 1 to 9. Optionally, the flame-retardant epoxy resin material comprises 0.1 wt% to 18 wt% of ammonium dihydrocarbylphosphinate salt and 82 wt% to 99.9 wt% of epoxy resin. The flame-retardant polymer material according to feature 13 or 14.

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