Dialkylphosphinic acid hybrid salts, method for preparing the same, and use thereof

Abstract

The present invention discloses a dialkylphosphinic acid hybrid salt, a method for preparing the same, and uses thereof. The dialkylphosphinic acid hybrid salt is at least one selected from compounds having a chemical formula represented by formula (I). The dialkylphosphinic acid hybrid salt having the composition of formula (I) provided by the present invention has a small addition amount, high flame retardancy efficiency for various polymer materials, good thermal stability, overcomes the drawback that the flame retardancy efficiency of diethylphosphinate for polymer materials is low, and at the same time overcomes the drawbacks that the long-chain dialkylphosphinate has low thermal stability and a large amount of smoke during combustion. Therefore, it can be widely used for flame retardancy of polymer materials that require high-temperature processing.

Description

Technical Field

[0001] The present invention relates to a dialkylphosphinic acid hybrid salt, a method for preparing the same, and use thereof, and particularly belongs to the field of preparing flame-retardant polymer materials.

Background Art

[0002] Dialkylphosphinate salts, particularly aluminum diethylphosphinate, are widely used as halogen-free flame retardants for polymer materials. However, conventional dialkylphosphinate salts have limited flame retardancy efficiency for glass fiber-reinforced polymer materials and need to be used together with a synergist. US Patents US6207736, US6255371, US6547992, etc. disclose that dialkylphosphinate salts and inorganic compounds such as ammonium polyphosphate, melamine polyphosphate, and / or zinc stannate synergistically provide flame-retardant glass fiber-reinforced polyamides and polyesters. However, the dosage of the flame retardant is large, the thermal stability of ammonium polyphosphate is not high, and melamine polyphosphate is easy to migrate.

[0003] US Patent US7420007 discloses aluminum diethylphosphinate containing 6% or less of a telomeric phosphinate salt, i.e., a long-chain dialkylphosphinate salt. Chinese Patent CN104072537B discloses a method for removing long-chain dialkylphosphinate salts during the preparation process of aluminum diethylphosphinate. All of these patents emphasize avoiding the generation and use of long-chain dialkylphosphinate salts with high content and low thermal stability. In actual use, when using a long-chain dialkylphosphinate salt, such as aluminum dibutylphosphinate, to flame-retard glass fiber-reinforced polyamide, there is a lot of smoke, which is disadvantageous for safe evacuation. A flame retardant with high flame retardancy effect and less smoke generation during combustion has always been the goal pursued by the industry.

[0004] Surprisingly, a hybrid salt composed of long-chain dialkylphosphinic acid ions and diethylphosphinic acid ions with relatively high contents has high thermal stability and very high flame retardancy efficiency. Therefore, it is not necessary to use a synergist, and flame retardancy of polymer materials can be achieved even by using it alone. Moreover, when the material flame-retarded thereby burns, there is less smoke.

Summary of the Invention

[0005] In order to solve the above technical problems, the present invention provides a dialkylphosphinic acid hybrid salt, a method for preparing the same, and its use. The dialkylphosphinic acid hybrid salt has a dialkylphosphinic acid hybrid salt represented by formula (I). The hybrid salt has high thermal stability, a small addition amount, high flame retardancy efficiency for various polymer materials, less smoke, can meet the processing requirements of engineering plastics that require high temperature, and has high economic efficiency.

[0006] According to a first aspect of the present invention, a dialkylphosphinic acid hybrid salt is provided. The dialkylphosphinic acid hybrid salt is at least one selected from compounds having a chemical formula represented by formula (I). JPEG2025521365000002.jpg20170Wherein, M is a central atom, and R1 and R2 are each independently selected from C4-C 12 alkyl groups, and at least one of R1 and R2 is not an isobutyl group. Diethylphosphinic acid ion, ethyl R1 group phosphinic acid ion, and R1 group R2 group phosphinic acid ion are all ligands. M is selected from metal elements, and the metal element is at least one selected from Group IIA, IIIA, IVA, VA metal elements, transition metal elements, and lanthanoid metal elements. n is the valence of the metal element M, and n is selected from 2, 3 or 4. At least two of the acid ions of ethyl R1 group phosphinic acid ion, diethylphosphinic acid ion, and R1 group R2 group phosphinic acid ion coordinate to the same central atom M, and one of them must be an ethyl R1 group phosphinic acid ion as the ligand coordinating to the central atom M. 0 ≦ x ≦ 0.76, 0.05 ≦ y ≦ 0.76, 0 ≦ z ≦ 0.76, and x + y + z = 1.

[0007] In the examples of the present invention, R1 and R2 are each independently selected from C4-C 12 alkyl groups. They may be the same or different. At least one of R1 and R2 is not an isobutyl group. The C4-C 12 alkyl group may be a linear or branched alkyl, including but not limited to n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, sec-pentyl group, tert-pentyl group, n-hexyl group, isohexyl group, sec-hexyl group, tert-hexyl group, n-heptyl group, isoheptyl group, sec-heptyl group, tert-heptyl group, n-octyl group, isooctyl group, sec-octyl group, tert-octyl group, n-nonyl group, sec-nonyl group, tert-nonyl group, n-decyl group, isodecyl group, sec-decyl group, tert-decyl group, n-undecyl group, isoundecyl group, sec-undecyl group, tert-undecyl group, n-dodecyl group, isododecyl group, sec-dodecyl group, tert-dodecyl group.

[0008] In the present invention, when there is a mixture of isomers in R1 or R2, when calculating the y value, substances that are isomers of each other are calculated as the same substance. For example, when R1 is a butyl group, it includes an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group. When calculating y of formula (I), ethylbutylphosphinic acid ion (R1 = butyl in formula (1)) includes ethyl-n-butylphosphinic acid ion, ethylisobutylphosphinic acid ion, ethyl-sec-butylphosphinic acid ion, and ethyl-tert-butylphosphinic acid ion. y is the ratio of the total number of moles of these four types of ethylbutylphosphinic acid ions to the total number of moles of all dialkylphosphinic acid ions (that is, the sum of the number of moles of diethylphosphinic acid ion, the number of moles of ethylbutylphosphinic acid ion, and the number of moles of phosphinic acid ion with R1 group and R2 group). When calculating z of formula (I), when there are isomers in both R1 and R2, similarly, substances that are isomers of each other are calculated as the same substance by the above method. In the examples of the present invention, in formula (I), when x exceeds 0.76, the flame retardancy decreases. When Z exceeds 0.76, the thermal stability decreases, which is disadvantageous for the preparation and physical properties of flame-retardant polymer materials. When y exceeds 0.76, the preparation cost is high and the economy is poor.

[0009] Optionally, the lower limit of x is independently selected from 0, 0.01, 0.03, 0.05, 0.10, 0.15, 0.20, 0.25, 0.30, and the upper limit is independently selected from 0.76, 0.70, 0.67, 0.65, 0.60, 0.55, 0.50, 0.45, 0.40, 0.35.

[0010] Optionally, the lower limit of y is independently selected from 0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, and the upper limit is independently selected from 0.76, 0.70, 0.67, 0.65, 0.60, 0.55, 0.50, 0.45.

[0011] Optionally, the lower limit of z is independently selected from 0, 0.001, 0.005, 0.01, 0.02, 0.03, 0.05, 0.08, and the upper limit is independently selected from 0.76, 0.70, 0.67, 0.65, 0.60, 0.55, 0.50, 0.45, 0.40, 0.35, 0.30, 0.25, 0.20, 0.15, 0.10.

[0012] Optionally, the Group IIA metal element is at least one selected from Be, Mg, Ca, Sr, Ba. The Group IIIA metal element is Al. The Group IVA metal element is Sn. The Group VA metal element is Sb. The transition metal element is at least one selected from Fe, Zn, Cu, TI, Zr, Mn. The lanthanoid metal element is Ce.

[0013] Optionally, the metal element is at least one selected from Al, Zn, Ca, Fe.

[0014] Optionally, the metal element is Al and n = 3.

[0015] Optionally, 0 ≦ x ≦ 0.76, 0.05 ≦ y ≦ 0.67, 0.005 ≦ z ≦ 0.76.

[0016] Optionally, 0 ≦ x ≦ 0.70, 0.05 ≦ y ≦ 0.67, 0.005 ≦ z ≦ 0.70.

[0017] Optionally, 0.1 ≦ x ≦ 0.65, 0.30 ≦ y ≦ 0.67, 0.01 ≦ z ≦ 0.50.

[0018] Optionally, 0.30 ≦ x ≦ 0.65, 0.30 ≦ y ≦ 0.65, 0.02 ≦ z ≦ 0.40.

[0019] In the examples of the present invention, the larger the z value, the earlier the thermogravimetric reduction of the dialkylphosphinic acid hybrid salt occurs.

[0020] The dialkylphosphinic acid hybrid salts in the present invention are not simple physical mixtures of different dialkylphosphinate salts. For example, when R1 and R2 are butyl groups, it is not a simple mixture composed of aluminum diethylphosphinate, aluminum ethylbutylphosphinate, and aluminum dibutylphosphinate, but a hybrid salt composed of at least two acid ions among diethylphosphinate ions, ethylbutylphosphinate ions, and dibutylphosphinate ions coordinated to the same aluminum atom, and one ligand of this hybrid salt is ethylbutylphosphinate ion. The X-ray diffraction spectra (XRD) of these hybrid salts are significantly different from the XRD spectra of physical mixed salts of simple dialkylphosphinate salts. The dialkylphosphinic acid hybrid salt having the composition of formula (I) shows a single peak in the region of the strongest absorption peak in the XRD spectrum. In contrast, the physical mixed salt obtained by simply mixing aluminum diethylphosphinate and aluminum dibutylphosphinate shows two completely independent peaks in the XRD spectrum, and their d values are close to the respective d values of aluminum diethylphosphinate and aluminum dibutylphosphinate.

[0021] In an embodiment of the present invention, after simply mixing a dialkylphosphinic acid hybrid salt having the composition of formula (I) with aluminum diethylphosphinate or aluminum dibutylphosphinate, two independent peaks also appear in the region of the strongest absorption peak in their XRD spectra. From these results, it is strongly indicated that the dialkylphosphinic acid hybrid salt having the composition of formula (I) obtained in the present invention is not a simple mixture of aluminum diethylphosphinate, aluminum ethyl R1 group phosphinate, and aluminum R1 group R2 group phosphinate, but has a structure in which at least two acid ions among diethylphosphinic acid ions, ethyl R1 group phosphinic acid ions, and R1 group R2 group phosphinic acid ions are coordinated with the same aluminum atom, and one of the ligands is ethyl R1 group phosphinic acid ion.

[0022] In an embodiment of the present invention, at the same dosage, pure aluminum long-chain dialkylphosphinate (R1, R2 are C4-C 12 alkyl groups) has low thermal stability, it is difficult to meet the requirements of polymer materials that require high-temperature processing, and the flame retardant efficiency is not high. During actual use, when a polymer flame-retarded with aluminum long-chain dialkylphosphinate burns, there is more smoke compared to the system flame-retarded with aluminum diethylphosphinate. However, even when pure aluminum diethylphosphinate is used alone, the flame retardant efficiency is not high. When used alone, it is difficult to impart a good flame retardant effect to polymer materials. In contrast, the dialkylphosphinic acid hybrid salt having the composition of formula (I) has higher thermal stability, less smoke, and a higher flame retardant effect than pure aluminum diethylphosphinate and pure aluminum long-chain dialkylphosphinate, which is very unexpected.

[0023] According to a second aspect of the present invention, a method for preparing the dialkylphosphinic acid hybrid salt is provided. The preparation method is as follows It includes the step of reacting a raw material containing mixture A and a metal element M source in an aqueous phase to obtain the dialkylphosphinic acid hybrid salt. The mixture A includes diethylphosphinic acid and / or its alkali metal salt, ethyl R1 group phosphinic acid and / or its alkali metal salt, and R1 group R2 group phosphinic acid and / or its alkali metal salt.

[0024] Optionally, the conditions for the reaction I are a temperature of 0 - 250 °C, a pressure of 0.1 MPa - 10 MPa, and a time of 0.01 - 20 h.

[0025] Optionally, the reaction I is carried out at a pH of 0 - 4.

[0026] Optionally, the metal element is Al, and the pH of the reaction I is 0 - 4, preferably 1 - 3.5, more preferably 2.3 - 3.3.

[0027] Specifically, in the reaction I, if the pH is too low, no precipitation occurs. If the pH is too high, metal ion hydroxides are generated and impurities are mixed in.

[0028] Optionally, the molar ratio of the diethylphosphinic acid and / or its alkali metal salt, ethyl R1 group phosphinic acid and / or its alkali metal salt, R1 group R2 group phosphinic acid and / or its alkali metal salt to the metal element M source is x:y:z:q or close to it. Here, q = 1 / n.

[0029] Optionally, the molar ratio of the diethylphosphinic acid and / or its alkali metal salt, ethyl R1 group phosphinic acid and / or its alkali metal salt to the R1 group R2 group phosphinic acid and / or its alkali metal salt in the mixture A is the same as or substantially the same as the ratio of x, y, z in formula (I).

[0030] Due to the difference in M, the solubility of the hybrid salt in water varies. For the hybrid salt with high solubility, the value calculated based on the number of moles of diethylphosphinic acid and / or its alkali metal salt, ethyl R1 group phosphinic acid and / or its alkali metal salt, R1 group R2 group phosphinic acid and / or its alkali metal salt in the mixture A is different from the values of x, y, z in the hybrid salt, so the molar ratio with the M source also changes. Also, in order to obtain more M-containing precipitate, when adding raw materials, the molar ratio of x, y, z corresponding to the reactants and M may exceed the theoretical calculated value.

[0031] In the actual operation process, the actual values of x, y, z and q are determined by phosphorus nuclear magnetic resonance.

[0032] Optionally, the obtaining of the mixture A includes the following steps. Ethylene and C4-C 12 olefin are introduced into an aqueous solution containing phosphinic acid and / or its alkali metal salt and a free radical initiator, and reaction II is carried out to obtain the mixture A.

[0033] Optionally, the molar ratio of the phosphinic acid and / or its alkali metal salt, ethylene, C4-C 12 olefin is 1:0.24 - 1.76:1.76 - 0.24.

[0034] In the actual reaction, due to some side reactions such as the polymerization of ethylene and / or C4-C 12 olefin to obtain longer-chain dialkylphosphinate, the consumption of ethylene and / or C4-C 12 olefin is higher than the theoretical value.

[0035] Optionally, the phosphinic acid and / or its alkali metal salt, ethylene, C4-C 12The molar ratio of the olefin is the same as or close to the theoretical value calculated according to the values of n, x, y, and z in formula (I). In the reaction process of phosphinic acid or its alkali metal salt with ethylene or other olefins, the y value has a maximum value less than 1. Depending on the type of olefin, this maximum value is 0.76 or less, and generally about 0.66. After reaching this maximum value, since x or z increases, y does not reach 1. When attempting to prepare y = 1, it is necessary to separate and purify the product of the reaction intermediate and remove diethylphosphinic acid and / or its alkali metal salt and the phosphinic acid and / or its alkali metal salt of the R1 group and R2 group, which is disadvantageous in terms of economy.

[0036] Specifically, in reaction II, ethylene and C4-C 12 The charging order of the olefins can be exchanged with each other, they can be charged simultaneously, or a part can be charged first.

[0037] Optionally, in reaction II, the phosphinic acid and / or its alkali metal salt first reacts with C4-C 12 olefin to obtain the corresponding y and z values, and then further reacts completely or almost completely with ethylene. Almost completely means that in the reaction mixture, the total phosphorus contained in ethylphosphinic acid ions, R1 group phosphinic acid ions, R2 group phosphinic acid ions, and phosphinic acid ions is less than 5% mol of the total phosphorus in the reaction solution.

[0038] Optionally, in the reaction II system, the mass of the water is 10 - 99% of the total mass of the aqueous solution.

[0039] Specifically, in the reaction II system, if there is too little water, the solubility of the olefin in water will decrease due to the salting-out effect, and the reaction rate will slow down. On the other hand, if there is too much water, the utilization rate of the reactor will decrease.

[0040] Optionally, in the reaction II system, the mass of the water is 20 - 95% of the total mass of the aqueous solution.

[0041] Optionally, in the reaction II system, the mass of the water is 45-92% of the total mass of the aqueous solution.

[0042] Optionally, in the reaction II system, the mass of the water is 50-90% of the total mass of the aqueous solution.

[0043] Optionally, in the reaction II system, the mass of the water is 55-90% of the total mass of the aqueous solution.

[0044] Optionally, the conditions of the reaction II are a temperature of 0-250°C, a time of 0.01-50 h, and a pressure of 0-3 MPa.

[0045] Specifically, if the temperature of the reaction II is too low, the reaction rate will be slow, while if the temperature is too high, the phosphinate will be easily decomposed.

[0046] Optionally, the temperature of the reaction II is 10-200°C.

[0047] Specifically, when the pressure of the reaction II is higher than 3 MPa, the requirements for the reaction equipment become higher and the operation becomes difficult.

[0048] Optionally, the pressure of the reaction II is 0.2-1.5 MPa.

[0049] Optionally, the molar ratio of the free radical initiator to the phosphinic acid and / or its alkali metal salt is 0.001-0.1:1.

[0050] Optionally, the molar ratio of the free radical initiator to the phosphinic acid and / or its alkali metal salt is 0.003-0.05:1.

[0051] Optionally, the free radical initiator is at least one selected from azo initiators, peroxide initiators, and photoinitiators. Here, the addition amount of the free radical initiator can be determined according to actual needs.

[0052] Optionally, the azo initiator is selected from cationic and / or non-cationic azo initiators, and includes one or more of azobisisobutyronitrile, 4,4'-azobis(4-cyanovaleric acid), 2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(2-amidinopropane) dihydrochloride, and 2,2'-azodipropylamidine dihydrochloride.

[0053] Optionally, the peroxide initiator is preferably an inorganic peroxide and an organic peroxide, and particularly preferably, it is one or more of hydrogen peroxide, ammonium persulfate, potassium persulfate, sodium persulfate, sodium percarbonate, benzoyl peroxide, di-tert-butyl peroxide, tert-butyl perbenzoate, and peracetic acid.

[0054] Preferably, the free radical initiator is a peroxide initiator. Particularly preferably, the free radical initiator is one selected from ammonium persulfate, potassium persulfate, and sodium persulfate.

[0055] Optionally, the acquisition of the mixture A includes the following steps. Introduce and react C4-C 12 olefin into an aqueous solution containing phosphinic acid and / or its alkali metal salt and a free radical initiator. After the molar ratio of the introduced C4-C 12 olefin to the total phosphorus of phosphinic acid and / or its alkali metal salt reaches (y + 2z) / 1 of formula (I), stop the introduction of C4-C 12 olefin, and then continue to introduce and react ethylene to obtain the mixture A. Here, the C4-C 12 olefin may be pure C4-C 12 olefin or C4-C 12 mixed olefin.

[0056] Optionally, the acquisition of the mixture A includes the following steps. Introduce C4-C 12 olefin into an aqueous solution containing phosphinic acid and / or its alkali metal salt and a free radical initiator. The C4-C12 After the olefin of C4-C has completely or almost completely reacted, ethylene is continuously introduced and reacted to obtain the mixture A. Here, C4-C 12 The olefin may be pure C4-C 12 olefin or a mixed olefin of C4-C 12 may be used.

[0057] Optionally, phosphinic acid and / or its alkali metal salt is reacted with the C4-C 12 olefin to obtain a single R1-group phosphinic acid or its alkali metal salt having a y value or a value substantially close to the y value, control z to 0.76 or less, and then stop the introduction of the C4-C 12 olefin, instead start introducing ethylene, continuously react in the presence of an initiator, and then react with the necessary metal salt to obtain a flame retardant having the formula (I). Here, C4-C 12 The olefin may be pure C4-C 12 olefin or a mixed olefin of C4-C 12 may be used.

[0058] Optionally, the obtaining of the mixture A includes the following steps. Introduce C4-C 12 olefin and a part of ethylene into an aqueous solution containing phosphinic acid and / or its alkali metal salt and a free radical initiator, and after the C4-C 12 olefin and a part of ethylene have completely or almost completely reacted, continuously introduce the remaining ethylene and react to obtain the mixture A. Here, C4-C 12 The olefin may be pure C4-C 12 olefin or a mixed olefin of C4-C 12 may be used.

[0059] Optionally, the obtaining of the mixture A includes the following steps. Introduce C4-C 12Introduce olefin and a part of ethylene and cause them to react. The molar ratio of ethylene to the total phosphorus of phosphinic acid and / or its alkali metal salt is less than (2x + y) / 1 of formula (I). The introduced C4-C 12 After the molar ratio of olefin to the total phosphorus of phosphinic acid and / or its alkali metal salt reaches (y + 2z) / 1 of formula (I), C4-C 12 Stop introducing olefin, and continue to introduce the remaining ethylene and cause it to react to obtain the mixture A. Here, C4-C 12 The olefin may be pure C4-C 12 olefin or a mixed olefin of C4-C 12 It may also be.

[0060] Optionally, obtaining the mixture A includes the following steps. Introduce a part of ethylene into an aqueous solution containing phosphinic acid and / or its alkali metal salt and a free radical initiator. The molar ratio of the part of ethylene to the total phosphorus of phosphinic acid and / or its alkali metal salt is (2x + y) / 1 or less of formula (I). After the part of ethylene has completely reacted, continue to introduce C4-C 12 olefin and cause it to react. After the molar ratio of the introduced C4-C 12 olefin to the total phosphorus of phosphinic acid and / or its alkali metal salt reaches (y + 2z) / 1 of formula (I), C4-C 12 Stop introducing olefin, and continue to introduce the remaining ethylene and cause it to react to obtain the mixture A. Here, C4-C 12 The olefin may be pure C4-C 12 olefin or a mixed olefin of C4-C 12 It may also be.

[0061] Optionally, obtaining the mixture A includes the following steps. Introduce a part of ethylene into an aqueous solution containing phosphinic acid and / or its alkali metal salt and a free radical initiator. After the part of ethylene has completely or almost completely reacted, continue to introduce C4-C 12 olefin and cause it to react. The C4-C 12After the olefin has reacted completely or almost completely, the remaining ethylene is introduced and reacted to obtain the mixture A. Here, C4-C 12 The olefin may be pure C4-C 12 olefin or a mixed olefin of C4-C 12 It may be.

[0062] Optionally, the molar ratio of the total amount of the ethylene to the C4-C 12 olefin is 0.14 - 7.33:1.

[0063] Optionally, the metal element M source is at least one selected from metal element M salts.

[0064] Optionally, the metal element M salt is at least one selected from nitrates, sulfates, hydrochlorides, acetates, and oxides of the metal element M.

[0065] Optionally, phosphinic acid and / or its alkali metal salt react with C4-C 12 olefin and a part of ethylene in the presence of a free radical initiator to control the amounts of C4-C 12 olefin and ethylene. When the molar percentage of ethyl R1 group phosphinic acid or its alkali metal salt in the reaction system is close to the y value, and the molar percentage of R1 group R2 group phosphinic acid or its alkali metal salt is close to the z value, and z is 0.76 or less, the introduction of C4-C 12 olefin is stopped, and then the remaining ethylene is continuously introduced and reacted continuously until it reacts completely in the presence of an initiator, and then it is reacted with the necessary metal salt to obtain a dialkylphosphinic acid hybrid salt having the formula (I). Here, C4-C 12 olefin may be pure C4-C 12 olefin or a mixed olefin of C4-C 12 It may be.

[0066] Optionally, the acquisition of the mixture A includes the following steps. Ethylene is introduced into an aqueous solution containing phosphinic acid and / or its alkali metal salt and a free radical initiator, the amount of ethylene is controlled, and after the molar ratio of the introduced ethylene to the total phosphorus of phosphinic acid and / or its alkali metal salt reaches (y + 2x) / 1 of formula (I), the introduction of ethylene is stopped, and subsequently C4-C 12 olefins are added, and the reaction is continued in the presence of an initiator until complete reaction to obtain the mixture A. Here, C4-C 12 olefins may be pure C4-C 12 olefins or C4-C 12 mixed olefins.

[0067] Specifically, after the completion of Reaction II, it is not necessary to separate diethylphosphinic acid, ethyl R1 group phosphinic acid, R1 group R2 group phosphinic acid and / or its alkali metal salt, and it can be directly used in the next reaction.

[0068] According to the third aspect of the present invention, a flame retardant is provided. The flame retardant is at least one selected from the dialkylphosphinic acid hybrid salts and the dialkylphosphinic acid hybrid salts prepared by the method.

[0069] Optionally, the flame retardant further contains at least one selected from phosphates, phosphites, alkylphosphonates, and alkylphosphinates. The molar content of these phosphorus-containing impurities in the flame retardant is 10% or less, and the number of moles of the flame retardant is calculated by the number of moles of phosphorus element contained therein.

[0070] According to the fourth aspect of the present invention, a flame retardant material is provided. The flame retardant material includes a flame retardant P and a thermoplastic polymer material. The flame retardant P is at least one selected from the flame retardants.

[0071] Optionally, the mass content of the flame retardant P in the flame retardant material is 1-35%.

[0072] Optionally, the flame retardant material contains 1-35 wt% of flame retardant P and 65-99 wt% of a thermoplastic polymer material.

[0073] In the present invention, the thermoplastic polymer material refers to a plastic having the property of softening when heated and hardening when cooled.

[0074] Specifically, the amount of the flame retardant P used depends on the thermoplastic polymer material.

[0075] Optionally, the mass content of the flame retardant P in the flame retardant material is 3-20%.

[0076] Optionally, the flame retardant material further contains a functional additive. The functional additive includes at least one selected from a reinforcing agent, a dripping inhibitor, a stabilizer, a pigment, a dye, a carbon formation catalyst, a dispersant, a nucleating agent, an inorganic filler, and an antioxidant. Preferably, the mass content of the functional additive in the flame retardant material is 5-40%.

[0077] Optionally, the reinforcing agent is selected from glass fibers.

[0078] Optionally, the dripping inhibitor is selected from Teflon.

[0079] Optionally, the inorganic filler is at least one selected from mica, calcium carbonate, calcium oxide, and silica.

[0080] Optionally, the flame retardant material further contains a flame retardant Q. The flame retardant Q is at least one selected from a nitrogen-based flame retardant and a boron-based flame retardant.

[0081] Optionally, the nitrogen-based flame retardant is at least one selected from melamine cyanurate, melamine polyphosphate, and ammonium polyphosphate. The boron-based flame retardant is selected from zinc borate.

[0082] Optionally, the flame retardant Q has a mass content of 0.5-20% in the flame retardant material.

[0083] Optionally, the thermoplastic polymer material is at least one selected from polyamide and polyester.

[0084] Optionally, the polyamide is at least one selected from aliphatic polyamide, aromatic polyamide, semi-aromatic polyamide, and a copolymer of semi-aromatic polyamide and aliphatic polyamide.

[0085] According to the common knowledge in the technical field, polyamide is also called nylon and is a general term for polymers containing -NH-C(O)- amide groups in the structural unit. It is synthesized by the condensation or ring-opening reaction of one or more dicarboxylic acids and one or more diamines, and / or one or more amino acids, and / or one or more lactams. According to the composition of its main chain, polyamide is usually divided into aliphatic polyamide, aromatic polyamide, and semi-aromatic polyamide. Semi-aromatic polyamide refers to the fact that at least one monomer structure of the synthetic monomers contains an aromatic group.

[0086] Optionally, the aliphatic polyamide is one or more mixtures arbitrarily selected from a copolymer of polyamide 6 and polyamide 66, polyamide 6, and polyamide 66.

[0087] Optionally, the semi-aromatic polyamide can be prepared using any one or more aromatic dicarboxylic acids and any one or more aliphatic diamines, or can also be prepared using any one or more aromatic diamines and any one or more aliphatic dicarboxylic acids. One or more selected from dicarboxylic acids, diamines, lactams and amino acids can be further added to the reaction system to prepare a polyamide copolymer having corresponding performance. The added dicarboxylic acid is an aromatic dicarboxylic acid and / or an aliphatic dicarboxylic acid. The added diamine is an aromatic diamine and / or an aliphatic diamine. The added lactam may be an aliphatic or aromatic lactam. The added amino acid may be an aromatic or aliphatic amino acid.

[0088] Optionally, the semi-aromatic polyamide is prepared using any one or more aromatic dicarboxylic acids selected from terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid and any one or more aliphatic diamines selected from butanediamine, hexamethylenediamine, octanediamine, decanediamine, 2-methylpentanediamine.

[0089] Optionally, the semi-aromatic polyamide is prepared using an aliphatic diamine, an aromatic dicarboxylic acid and an aliphatic dicarboxylic acid.

[0090] Optionally, the semi-aromatic polyamide is prepared using an aliphatic diamine and an aromatic dicarboxylic acid. Optionally, an aliphatic dicarboxylic acid can be further added. The molar fraction of the aliphatic dicarboxylic acid is 0-45% of the total amount of dicarboxylic acids. That is, the number of moles of aliphatic dicarboxylic acid / (the number of moles of aliphatic dicarboxylic acid + the number of moles of aromatic dicarboxylic acid) = 0-45%.

[0091] Optionally, the aromatic dicarboxylic acid is one or more selected from terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid. The aliphatic diamine is one or more selected from butanediamine, hexamethylenediamine, octanediamine, decanediamine, and 2-methylpentanediamine. The aliphatic dicarboxylic acid is one or more selected from adipic acid, succinic acid, sebacic acid, and suberic acid.

[0092] Optionally, the polyamide is one or more selected from polyhexamethylene terephthalamide (abbreviation: PA6T), polyhexamethylene isophthalamide (abbreviation: PA6I), terephthalic acid / hexamethylenediamine / caprolactam copolymer (abbreviation: PA6T / 6), terephthalic acid / hexamethylenediamine / adipic acid copolymer (abbreviation: PA6T / 66), terephthalic acid / hexamethylenediamine / adipic acid / isophthalic acid copolymer (abbreviation: PA6T / 6I / 66), polynonamethylene terephthalamide (abbreviation: PA9T), polydecandiamine terephthalamide (abbreviation: PA10T), polydodecyl terephthalamide (abbreviation: PA12T), terephthalic acid / hexamethylenediamine / dodecyl lactam copolymer (abbreviation: PA6T / 12), poly(m-xylylene adipamide) (abbreviation: MXD6), terephthalic acid / hexamethylenediamine / 2-methylpentanediamine copolymer (abbreviation: PA6T / 2-MPMDT), and terephthalic acid / 2,2,4-trimethylhexamethylenediamine / 2,4,4-trimethylhexamethylenediamine copolymer.

[0093] Optionally, the aliphatic polyamide is at least one selected from polyamide 6, polyamide 66, and a copolymer of polyamide 6 and polyamide 66.

[0094] Optionally, the semi-aromatic polyamide is selected from polyphthalamide (PPA).

[0095] Optionally, the polyester is selected from polybutylene terephthalate (PBT).

[0096] In the examples of the present invention, the values of x, y, and z in formula (I) are such that x + y + z = 1 and x + z > 0 without considering the amounts of other phosphorus-containing impurities. The flame retardant having the composition of formula (I) may contain trace amounts of other phosphorus-containing impurities. Due to the presence of impurities in the raw materials or the generation of impurities during the synthesis process, some trace amounts of phosphates, phosphites, alkylphosphonates, and alkylphosphinates may be present in the flame retardant. Some ethylene and / or C4-C 12 Telomer products obtained by polymerizing or copolymerizing olefins, such as ethyl-n-tetradecylphosphinate and ethylhexadecylphosphinate, may also be present as impurities in the flame retardant having the composition of formula (I). However, if the total molar amount of these other phosphorus-containing acid ions is 5% or less of the total phosphorus molar amount, it will not affect the normal action of the flame retardant having the composition of formula (I).

[0097] In the examples of the present invention, the ratios of x, y, and z in formula (I) can be determined by 31 P-NMR (nuclear magnetic resonance) after subjecting the flame retardant to alkaline hydrolysis or acid hydrolysis. Diethylphosphinate ions, ethyl R1 group phosphinate ions, and R1 group R2 group phosphinate ions have different 31 chemical shifts of P, and 31 independent peaks often appear in the P-NMR spectrum.

[0098] The peak areas of these peaks correspond to the molar concentrations of the respective dialkylphosphinate ions. Among them, some dialkylphosphinate ions having the same chemical formula may have isomers, so they may show different peaks in the phosphorus nuclear magnetic resonance spectrum. When calculating the x, y, and z values, these isomers are calculated as the same substance. For example, when R1 and R2 are butyl groups, the 31Five groups of peaks appear in the ³¹P-NMR spectrum. These five groups of peaks correspond to ethyl-sec-butylphosphinic acid ions, n-butyl-sec-butylphosphinic acid ions, diethylphosphinic acid ions, ethyl-n-butylphosphinic acid ions, and di-n-butylphosphinic acid ions, respectively. Here, the molar concentration of diethylphosphinic acid ions corresponds to x, the sum of the molar concentrations of ethyl-sec-butylphosphinic acid ions and ethyl-n-butylphosphinic acid ions (collectively referred to as the molar concentration of ethylbutylphosphinic acid ions) corresponds to y, and the sum of the molar concentrations of di-n-butylphosphinic acid ions and n-butyl-sec-butylphosphinic acid ions (collectively referred to as the molar concentration of dibutylphosphinic acid ions) corresponds to z. The ratio of the three is the values of x, y, and z. In this case, telomeric dialkylphosphinic acid ions exist, their amounts are very small, and their chemical shifts are close to those of the corresponding dialkylphosphinic acid ions. Therefore, when integrating, they are attributed to the corresponding dialkylphosphinic acid ions.

[0099] The beneficial effects of the present invention are as follows. (1) The dialkylphosphinic acid hybrid salt having the composition of formula (I) provided by the present invention has a small addition amount, high thermal stability, high flame retardancy efficiency for polymer materials, and high economic efficiency. It overcomes the drawback that the flame retardancy efficiency for polymer materials is low when diethylphosphinate and long-chain dialkylphosphinate are used alone, and also overcomes the drawbacks that the long-chain dialkylphosphinate has low thermal stability and a large amount of flame-retardant smoke. Therefore, it can be widely used for flame retardancy of polymer materials that require high-temperature processing. (2) According to the present invention, a method for preparing a dialkylphosphinic acid hybrid salt is provided. It avoids the drawback that it is necessary to independently prepare different dialkylphosphinic acids, is environmentally friendly by using water as a reaction solvent, the raw materials are easily available, and it has high economic efficiency.

Brief Description of the Drawings

[0100]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0101] Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples.

[0102] Unless otherwise specified, all raw materials used in the examples of the present invention were purchased through commercial routes.

[0103] The raw materials used in the examples are as follows. PA66 (also known as polyamide 66 or nylon 66): Zytel 70G35 HSL NC010 from DuPont in the United States, with a glass fiber content of 35% by weight. PA6 (also known as polyamide 6 or nylon 6): Zytel 73G30L NC010 from DuPont in the United States, with a glass fiber content of 30% by weight. ADP: Aluminum diethylphosphinate, ExolIt OP1230 from Clariant in Germany MPP: Melamine polyphosphate, Suzhou Kema Chemical Technology Co., Ltd. Zinc borate: Sinopharm Chemical Reagent Co., Ltd. Antioxidant 1010: Pentaerythritol tetra[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], Shanghai Macklin Biochemical Co., Ltd. Antioxidant 168: Tris(2,4-di-tert-butylphenyl) phosphite, Strem in the United States Compound antioxidant: A mixture of antioxidant 1010 (pentaerythritol tetra[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]) and antioxidant 168 (tris(2,4-di-tert-butylphenyl) phosphite) in a weight ratio of 1:1. Combustion test standard: GB / T 2408-2008 standard Nuclear magnetic resonance - phosphorus (NMR) test: Instrument model numbers AVANCE III 600MHz and AVANCE III 400MHz used, Bruker in Germany Nuclear magnetic resonance - phosphorus spectrum 31 (P-NMR) test method: Preliminary delay D1 = 10 seconds, 32 scans, and the ratio of peak areas is taken as the ratio of the number of moles of each phosphonate ion. Model number of the instrument used for X-ray diffraction (XRD) test: D8 ADVANCE DAVINCI, Bruker in Germany Instrument model used for TGA thermogravimetric reduction treatment: Q500, TA in the United States, nitrogen atmosphere, heating rate 10°C / min

[0104] Example 1 Preparation of Hybrid Salt with Composition of Formula (I): x = 0.40, y = 0.56, z = 0.04, M = Al, n = 3 100 g of sodium phosphinate monohydrate was dissolved in 500 g of water, charged into a 1 L stainless steel pressure vessel, the reactor was purged twice with nitrogen gas, evacuated, and then butene was introduced until the pressure no longer rose. The reaction solution was heated to about 90 °C. After the pressure gauge showed 0.25 MPa, an aqueous sodium persulfate solution with a mass concentration of 4% was added at a constant rate of 10 ml / h. Butene was continuously introduced into the reactor, and the introduction amount of olefin was measured with a gas flow meter. After 4 hours, the introduction of butene was stopped and ethylene was introduced. After 12 hours, since the pressure of the reactor no longer decreased, it was cooled, the pressure was released, purged with N2, and the material was discharged to obtain a colorless transparent reaction solution. The reaction solution was sampled during and at the end of the reaction, 31 The results of measuring 31P-NMR nuclear magnetic resonance are shown in Table 1.

[0105]

Table 1

[0106] A part of the above solution, 307.59 g (containing 0.36 mol of phosphorus), was slowly mixed with 39.99 g of an aqueous solution containing aluminum sulfate octadecahydrate with a mass concentration of 10% at normal pressure. The reaction temperature was controlled at 70 °C, and the pH value was adjusted to 3.0 or less to obtain a large amount of precipitate. After adding and mixing the raw materials, it was kept warm for 0.5 h. It was hot-filtered, and the filter cake was washed with clear water until the pH > 4.5. Then, the filter cake was dried at 120 °C to obtain 48.15 g of a white solid. The sample was dissolved in an aqueous sodium hydroxide solution, and as a result of performing phosphorus nuclear magnetic resonance measurement, 31 As can be seen from the P-NMR spectrum, the molar content of diethylphosphinic acid ion was 40.23%, the molar content of ethyl-n-butylphosphinic acid ion was 51.98%, the molar content of ethyl-sec-butylphosphinic acid ion was 4.10%, and the molar content of di-n-butylphosphinic acid ion was 3.69%. The molar fractions of phosphinic acid ions with the same chemical formula were added (that is, the total of ethyl-n-butylphosphinic acid ion and ethyl-sec-butylphosphinic acid ion was used to calculate the y value), and x = 0.40, y = 0.56, and z = 0.04 were obtained by calculation.

[0107] As a result of performing XRD measurement on the sample, the interlayer distance corresponding to the characteristic peak with the highest relative intensity obtained by XRD measurement was 11.143 Å (100%).

[0108] Example 2 Preparation of a hybrid salt having the composition of formula (I): x = 0, y = 0.24, z = 0.76, M = Al, n = 3 100 g of sodium phosphinate monohydrate was dissolved in 500 g of water, charged into a 1 L stainless steel pressure vessel, and the reactor was purged twice with nitrogen gas and evacuated. Then, butene was introduced until the pressure no longer rose. The reaction solution was heated to about 90 °C. After the pressure gauge showed 0.25 MPa, an aqueous sodium persulfate solution with a mass concentration of 4% was added at a constant rate of 10 ml / h. Butene was continuously introduced into the reactor, and the introduction amount of olefin was measured with a gas flow meter. After 8.5 hours, the introduction of butene was stopped, and ethylene was started to be introduced. After 15 hours, since the pressure of the reactor no longer decreased, it was cooled, the pressure was released, purged with N2, and the material was discharged to obtain a colorless transparent reaction solution. The reaction solution was sampled and measured by nuclear magnetic resonance, 31 The results of 31P-NMR are shown in Table 2.

[0109]

Table 2

[0110] A part of the above solution, 353.74 g (containing 0.36 mol of phosphorus), was slowly mixed with 39.99 g of an aqueous solution containing 10% by mass of aluminum sulfate octadecahydrate at normal pressure, the reaction temperature was controlled at 70 °C, the pH value was adjusted to 3.0 or less, and a large amount of precipitate was obtained. After adding and mixing the raw materials, it was kept warm for 0.5 hour. It was hot-filtered, and the filter cake was washed with clear water until the pH > 4.5. Then, the filter cake was dried at 120 °C to obtain 66.54 g of a white solid. The sample was dissolved in an aqueous sodium hydroxide solution and measured by phosphorus nuclear magnetic resonance. As a result, 31As can be seen from the P-NMR spectrum, the molar content of ethyl-sec-butylphosphinic acid ions is 2.42%, the molar content of ethyl-n-butylphosphinic acid ions is 21.13%, the molar content of n-butyl-sec-butylphosphinic acid ions is 7.25%, the molar content of di-n-butylphosphinic acid ions is 68.63%, and the total molar content of other phosphorus-containing impurities, such as butylphosphinic acid ions and butylphosphonic acid ions, is 0.57%. The molar fractions of phosphinic acid ions with the same chemical formula were added (i.e., the molar fractions of ethyl-n-butylphosphinic acid ions and ethyl-sec-butylphosphinic acid ions were added to calculate the y value. The molar fractions of n-butyl-sec-butylphosphinic acid ions, di-n-butylphosphinic acid ions, and the telomer of dialkylphosphinic acid were added to calculate the z value), and after normalization, x = 0, y = 0.24, and z = 0.76 were obtained.

[0111] As a result of performing XRD measurement on the sample, the interlayer distance corresponding to the characteristic peak with the highest relative intensity obtained by XRD measurement was 12.468 Å (100%).

[0112] Example 3 Preparation of a hybrid salt having the composition of formula (I): x = 0, y = 0.32, z = 0.68, M = Al, n = 3 100 g of sodium phosphinate monohydrate was dissolved in 500 g of water, charged into a 1 L stainless steel pressure vessel, the reactor was replaced with nitrogen gas twice, evacuated, and then butene was introduced until the pressure no longer increased. The reaction solution was heated to about 90 °C, and after the pressure gauge showed 0.25 MPa, an aqueous sodium persulfate solution with a mass concentration of 4% was added at a constant rate of 10 ml / h. Butene was continuously introduced into the reactor, and the introduction amount of olefin was measured with a gas flow meter. After 7 hours, the introduction of butene was stopped, and ethylene was introduced. After 15.5 hours, since the pressure of the reactor no longer decreased, it was cooled, the pressure was released, purged with N2, and the material was discharged to obtain a colorless transparent reaction solution. The reaction solution was sampled and measured by nuclear magnetic resonance. 31 The results of P-NMR are shown in Table 3.

[0113]

Table 3

[0114] A part of the above solution, 334.45 g (containing 0.36 mol of phosphorus), was slowly mixed with 39.99 g of an aqueous solution containing 10% by mass of aluminum sulfate octadecahydrate at normal pressure, the reaction temperature was controlled at 70 °C, the pH value was adjusted to 3.0 or less, and a large amount of precipitate was obtained. After adding and mixing the raw materials, it was kept warm for 0.5 h. It was hot-filtered, and the filter cake was washed with clear water until pH > 4.5. Then, the filter cake was dried at 120 °C to obtain 64.81 g of a white solid. The sample was dissolved in an aqueous sodium hydroxide solution, and phosphorus nuclear magnetic resonance measurement was performed. 31 The P-NMR spectrum is shown in Figure 3. 31 As can be seen from the P-NMR spectrum, the molar content of ethyl-sec-butylphosphinic acid ion is 2.45%, the molar content of ethyl-n-butylphosphinic acid ion is 29.44%, the molar content of n-butyl-sec-butylphosphinic acid ion is 6.83%, and the molar content of di-n-butylphosphinic acid ion is 61.28%. The molar fractions of phosphinic acid ions with the same chemical formula were added (that is, the molar fractions of ethyl-n-butylphosphinic acid ion and ethyl-sec-butylphosphinic acid ion were added to calculate the y value, and the molar fractions of n-butyl-sec-butylphosphinic acid ion and di-n-butylphosphinic acid ion were added to calculate the z value), and after normalization, x = 0, y = 0.32, and z = 0.68 were obtained.

[0115] As a result of performing XRD measurement on the sample, the interlayer distance corresponding to the characteristic peak with the highest relative intensity obtained by XRD measurement was 12.319 Å (100%).

[0116] Example 4 Preparation of a hybrid salt having the composition of formula (I): x = 0.02, y = 0.63, z = 0.35, M = Al, n = 3 100 g of sodium phosphinate monohydrate was dissolved in 500 g of water, charged into a 1 L stainless steel pressure vessel, and the reactor was purged twice with nitrogen gas and evacuated. Then, butene was introduced until the pressure no longer rose. The reaction solution was heated to about 90 °C. After the pressure gauge showed 0.25 MPa, an aqueous sodium persulfate solution with a mass concentration of 4% was added at a constant rate of 10 ml / h. Butene was continuously introduced into the reactor, and the introduction amount of olefin was measured with a gas flow meter. After 5.5 hours, the introduction of butene was stopped, and ethylene was started to be introduced. After 13 hours, since the pressure of the reactor no longer decreased, it was cooled, the pressure was released, purged with N2, and the material was discharged to obtain a colorless transparent reaction solution. The reaction solution was sampled and measured by nuclear magnetic resonance, 31 The results of 31P-NMR are shown in Table 4.

[0117]

Table 4

[0118] A part of the above solution, 329.57 (containing 0.36 mol of phosphorus), was slowly mixed with 39.99 g of an aqueous solution containing 10% by mass of aluminum sulfate octadecahydrate at normal pressure, the reaction temperature was controlled at 70 °C, the pH value was adjusted to 3.0 or less, and a large amount of precipitate was obtained. After adding and mixing the raw materials, it was kept warm for 0.5 hour. It was hot-filtered, and the filter cake was washed with clear water until the pH > 4.5. Then, the filter cake was dried at 120 °C to obtain 59.60 g of a white solid. The sample was dissolved in an aqueous sodium hydroxide solution, and phosphorus nuclear magnetic resonance measurement was performed. 31 The 31P-NMR spectrum is shown in Figure 4. 31As can be seen from the P-NMR spectrum, the molar content of diethylphosphinic acid ions is 1.99%, the molar content of ethyl-sec-butylphosphinic acid ions is 4.30%, the molar content of ethyl-n-butylphosphinic acid ions is 58.22%, the molar content of n-butyl-sec-butylphosphinic acid ions is 3.44%, the molar content of di-n-butylphosphinic acid ions is 30.67%, and the total content of other phosphorus-containing impurities, such as ethylphosphinic acid ions, butylphosphinic acid ions, ethylphosphonic acid ions, and butylphosphonic acid ions, is 1.38%. The molar fractions of phosphinic acid ions with the same chemical formula were added (i.e., the molar fractions of ethyl-n-butylphosphinic acid ions and ethyl-sec-butylphosphinic acid ions were added to calculate the y value, and the molar fractions of n-butyl-sec-butylphosphinic acid ions, di-n-butylphosphinic acid ions, and the telomer of dialkylphosphinic acid were added to calculate the z value. Here, the dialkylphosphinic acid telomer was also attributed to the nearby di-n-butylphosphinic acid ions), and after normalization, x = 0.02, y = 0.63, and z = 0.35 were obtained.

[0119] As a result of performing XRD measurement on the sample, the interlayer distance corresponding to the characteristic peak with the highest relative intensity obtained by XRD measurement was 11.934 angstroms (100%).

[0120] Example 5 Preparation of a hybrid salt having the composition of formula (I): x = 0.22, y = 0.67, z = 0.11, M = Al, n = 3 Dissolve 100 g of sodium phosphinate monohydrate in 500 g of water, put it into a 1 L stainless steel pressure vessel, replace the reactor with nitrogen gas twice, evacuate it, and then introduce butene. Heat the reaction solution to about 90 °C. After the pressure gauge shows 0.15 MPa, add an aqueous solution of sodium persulfate with a mass concentration of 4% at a constant rate of 10 ml / h, continue to introduce butene into the reactor, and measure the introduction amount of olefin with a gas flow meter. After 7.5 hours, stop the introduction of butene and start introducing ethylene. After 21 hours, since the pressure of the reactor hardly decreased, cool it, release the pressure, purge with N2, and discharge the material to obtain a colorless transparent reaction solution. Sample the reaction solution and measure it by nuclear magnetic resonance, 31 The results of P-NMR are shown in Table 5.

[0121]

Table 5

[0122] Take 374.84 g (containing 0.36 mol of phosphorus) of a part of the above solution and slowly mix it with 39.99 g of an aqueous solution containing 10% by mass of aluminum sulfate octadecahydrate at normal pressure, control the reaction temperature at 70 °C, adjust the pH value to 3.0 or less to obtain a large amount of precipitate. After adding and mixing the raw materials, keep warm for 0.5 hour. Filter while hot, and wash the filter cake with clear water until the pH > 4.5. Then, dry the filter cake at 120 °C to obtain 52.13 g of a white solid. The sample was dissolved in an aqueous sodium hydroxide solution and measured by phosphorus nuclear magnetic resonance. As a result, 31As can be seen from the P-NMR spectrum, the molar content of diethylphosphinate ions is 21.32%, the molar content of ethyl-sec-butylphosphinate ions is 4.52%, the molar content of ethyl-n-butylphosphinate ions is 62.02%, the molar content of n-butyl-sec-butylphosphinate ions is 1.11%, the molar content of di-n-butylphosphinate ions is 9.66%, and the total molar content of other phosphorus-containing impurities such as ethylphosphinate ions, butylphosphinate ions, ethylphosphonate ions, butylphosphonate ions, and phosphite ions was 1.37%. The molar fractions of phosphinate ions with the same chemical formula were added (i.e., the molar fractions of ethyl-n-butylphosphinate ions and ethyl-sec-butylphosphinate ions were added to calculate the y value, and the molar fractions of n-butyl-sec-butylphosphinate ions and di-n-butylphosphinate ions were added to calculate the z value), and after normalization, x = 0.22, y = 0.67, and z = 0.11 were obtained. As a result of performing XRD measurement on the sample, the interlayer distance corresponding to the characteristic peak with the highest relative intensity obtained by XRD measurement was 11.384 angstroms (100%).

[0123] Example 6 Preparation of a hybrid salt having the composition of formula (I): x = 0.59, y = 0.39, z = 0.02, M = Al, n = 3 100 g of sodium phosphinate monohydrate was dissolved in 500 g of water, charged into a 1 L stainless steel pressure vessel together with 39.7 g of hexene, the reactor was purged twice with nitrogen gas, evacuated, and then a part of ethylene was introduced. The reaction solution was heated to about 90 °C, and then an aqueous sodium persulfate solution with a mass concentration of 4% was added at a constant rate of 10 ml / h. After reacting for 8.5 hours, the remaining ethylene was started to be introduced. After 14.5 hours, since the pressure of the reactor no longer decreased, it was cooled, the pressure was released, purged with N2, and the material was discharged to obtain a colorless transparent reaction solution. The reaction solution was sampled and measured by nuclear magnetic resonance, 31 The results of P-NMR are shown in Table 6.

[0124]

Table 6

[0125] 367.37 g (containing 0.36 mol of phosphorus) of a part of the above solution was slowly mixed with 39.99 g of an aqueous solution containing 10% by mass of aluminum sulfate octadecahydrate at normal pressure, the reaction temperature was controlled at 70 °C, the pH value was adjusted to 3.0 or less, and a large amount of precipitate was obtained. After adding and mixing the raw materials, it was kept warm for 0.5 hour. It was hot-filtered, and the filter cake was washed with clear water until pH>4.5. Then, the filter cake was dried at 120 °C to obtain 50.35 g of a white solid. The sample was dissolved in an aqueous sodium hydroxide solution and subjected to phosphorus nuclear magnetic resonance measurement. As a result, 31 As can be seen from the P-NMR spectrum, the molar content of diethylphosphonic acid ions is 57.54%, the molar content of ethylhexylphosphonic acid ions is 38.19%, the molar content of dihexylphosphonic acid ions is 2.21%, and the total molar content of other phosphorus-containing impurities such as ethylphosphonic acid ions, hexylphosphonic acid ions, ethylphosphonate ions, hexylphosphonate ions, and phosphite ions is 2.06%. After normalization, x = 0.59, y = 0.39, and z = 0.02 were obtained. As a result of performing XRD measurement on the sample, the interlayer distance corresponding to the characteristic peak with the highest relative intensity obtained by XRD measurement was 11.639 Å (100%).

[0126] Example 7 Preparation of a hybrid salt having the composition of formula (I): x = 0.01, y = 0.52, z = 0.47, M = Cu, n = 2 A part (137.32) of the solution obtained in the first step of Example 4 above (containing 0.15 mol of phosphorus) was slowly mixed with 18.73 g of an aqueous solution containing 25% by mass of copper sulfate pentahydrate at normal pressure, the reaction temperature was controlled at 70 °C, the pH value was adjusted to less than 4, and a large amount of precipitate was obtained. After adding and mixing the raw materials, it was kept warm for 0.5 hour. It was hot-filtered, and the filter cake was washed with clear water until pH > 4.5. Then, the filter cake was dried at 120 °C, and 19.53 g of solid was obtained with a yield of 70%. The sample was dissolved in an aqueous sodium hydroxide solution, and as a result of performing phosphorus nuclear magnetic resonance measurement, 31 As can be seen from the P-NMR spectrum, the molar content of diethylphosphinic acid ions is 0.80%, the molar content of ethyl-sec-butylphosphinic acid ions is 2.76%, the molar content of ethyl-n-butylphosphinic acid ions is 49.60%, the molar content of n-butyl-sec-butylphosphinic acid ions is 4.48%, and the molar content of di-n-butylphosphinic acid ions is 42.36%. The molar fractions of phosphinic acid ions having the same chemical formula were added (that is, the y value was calculated using the total of ethyl-n-butylphosphinic acid ions and ethyl-sec-butylphosphinic acid ions), and x = 0.01, y = 0.52, z = 0.47 were obtained by calculation. Since the solubilities of different copper dialkylphosphinate salts are different, the yield of this example is low, and the finally obtained hybrid salt has significantly different x, y, z values from those of other metal hybrid salts obtained from the same phosphorus raw material with the same x, y, z values.

[0127] As a result of performing XRD measurement on the sample, the interlayer distance corresponding to the characteristic peak with the highest relative intensity obtained by XRD measurement was 14.292 angstroms (100%).

[0128] Figure 1 is a graph (TGA) of the thermal weight loss of hybrid salts (Example 1, Example 4, Example 5) having different x, y, and z values and aluminum diethylphosphinate and aluminum dibutylphosphinate (Comparative Example 1). As can be seen from the figure, the larger the z value, the lower the thermal stability of the hybrid salt, and the larger the x value, the higher the thermal stability.

[0129] Figure 2a is an XRD spectrum of hybrid salts (Examples 1 - 5) having different x, y, and z values, aluminum dibutylphosphinate (Comparative Example 1), aluminum diethylphosphinate (ADP), and a physical mixed salt of aluminum dibutylphosphinate and aluminum diethylphosphinate. Figure 2b is an enlarged view of a part of the strongest absorption peak in Figure 2a. As can be seen from Figure 2b, the simple physical mixed salt has two independent peaks in the region of the strongest absorption peak in the XRD spectrum, and their d values are close to the d values of aluminum diethylphosphinate and aluminum dibutylphosphinate, respectively. The hybrid salt having the composition of formula (I) has only one peak or overlapping peaks, and the d value is basically between the d values of aluminum diethylphosphinate and aluminum dibutylphosphinate. This shows that the dialkylphosphinic acid hybrid salt having the composition of formula (I) described in the present invention is not a simple mixture of aluminum diethylphosphinate, aluminum ethylbutylphosphinate, and aluminum dibutylphosphinate, but a hybrid salt having a structure in which at least two acid ions among diethylphosphinic acid ions, ethylbutylphosphinic acid ions, and dibutylphosphinic acid ions coordinate with the same aluminum atom.

[0130] Example 8 Polyamide PA66, the hybrid salt prepared in Example 1, and the composite antioxidant were mixed at a weight ratio of 79.6:20:0.4 in a closed mixer with a rotation speed of 50 rpm / min. The temperature was set at 280 °C, and after 5 minutes, it was taken out, cooled, and dried. Then, it was filled into a mold, preheated in a flat vulcanizer at 280 °C for 10 minutes, kept under pressure at 10 MPa for 5 minutes, and then cold pressed. After cooling, samples were cut out and tested. The flame retardant grade of the 1.6 mm sample was UL94 V-0.

[0131] Example 9 Polyamide PA6, the hybrid salt prepared in Example 1, and the composite antioxidant were mixed at a weight ratio of 79.6:20:0.4 in a closed mixer with a rotation speed of 50 rpm / min. The temperature was set at 260 °C, and after 5 minutes, it was taken out, cooled, and dried. Then, it was filled into a mold, preheated in a flat vulcanizer at 260 °C for 10 minutes, kept under pressure at 10 MPa for 5 minutes, and then cold pressed. After cooling, samples were cut out and tested. The flame retardant grade of the 1.6 mm sample was UL94 V-0.

[0132] Examples 10 - 22 Using the hybrid salts prepared in Examples 1 - 7, sample preparation and testing were carried out in polyamides PA66 and PA6 respectively according to the descriptions of Examples 8 and 9. The results are shown in Table 7.

[0133] Comparative Example 1: Preparation of Aluminum Dibutylphosphinate 100 g of sodium phosphinate monohydrate was dissolved in 500 g of water, put into a 1 L stainless steel pressure vessel, the reactor was purged with nitrogen gas twice and evacuated, and then butene was introduced until the pressure no longer rose. The reaction solution was heated to about 90 °C, and then an aqueous solution of sodium persulfate with a mass concentration of 4% was added at a constant rate of 10 ml / h. Butene was continuously introduced into the reactor, and the introduction amount of butene was measured by a gas flow meter. After 25.5 hours, since the pressure of the system no longer decreased, the reaction was stopped, cooled, the pressure was released, purged with N2, and the material was discharged to obtain a transparent reaction solution. The reaction solution was sampled and measured by nuclear magnetic resonance. 31As a result of the P-NMR, the molar content of n-butyl-sec-butylphosphinic acid was 10.56%, the molar content of di-n-butylphosphine was 84.92%, the molar content of dibutylphosphinic acid telomer was 3.52%, and the remaining 1.00% was by-products such as butylphosphinic acid, butylphosphonic acid and phosphorous acid.

[0134] A part (containing 0.3996 moles of phosphorus) of the above solution was slowly mixed with 44.38 g of an aqueous solution containing 10% by mass of aluminum sulfate octadecahydrate at normal pressure, the reaction temperature was controlled at 70 °C, the pH value was adjusted to 3.0 or less, and a large amount of precipitate was obtained. After adding and mixing the raw materials, it was kept warm for 0.5 hour. Slow hot filtration was carried out, and the filter cake was washed with clear water until the pH > 4.5. Then, the filter cake was dried at 120 °C to obtain 67.28 g of a white solid.

[0135] As a result of performing XRD measurement on the sample, the interlayer distance corresponding to the characteristic peak with the highest relative intensity obtained by XRD measurement was 12.770 angstroms (100%).

[0136] Comparative Example 2 Polyamide PA66, aluminum dibutylphosphinate prepared in Comparative Example 1, and a composite antioxidant were mixed at a weight ratio of 79.6:20:0.4 in a closed mixer with a rotation speed of 50 rpm / min, the temperature was set at 280 °C, taken out and cooled after 5 minutes, and dried. Then, it was filled into a mold, preheated in a flat vulcanizer at 280 °C for 10 minutes, kept under pressure at 10 MPa for 5 minutes, and then cold pressed. After cooling, a sample was cut out and tested. The flame retardant grade of the 1.6 mm sample was without UL94 grade.

[0137] Comparative Example 3 Polyamide PA6, aluminum dibutylphosphinate prepared in Comparative Example 1, and a composite antioxidant were mixed at a weight ratio of 79.6:20:0.4 using a sealed mixer with a rotation speed of 50 rpm / min. The temperature was set to 260 °C, and after 5 minutes, it was taken out, cooled, and dried. Then, it was filled into a mold, preheated in a flat vulcanizer at 260 °C for 10 minutes, held at a pressure of 10 MPa for 5 minutes, and then cold-pressed. After cooling, samples were cut out and tested. The flame retardancy grade of the 1.6 mm sample was UL-94 V-1.

[0138] Comparative Example 4 Polyamide PA66, aluminum diethylphosphinate, and a composite antioxidant were mixed at a weight ratio of 79.6:20:0.4 using a sealed mixer with a rotation speed of 50 rpm / min. The temperature was set to 280 °C, and after 5 minutes, it was taken out, cooled, and dried. Then, it was filled into a mold, preheated in a flat vulcanizer at 280 °C for 10 minutes, held at a pressure of 10 MPa for 5 minutes, and then cold-pressed. After cooling, samples were cut out and tested. The flame retardancy grade of the 1.6 mm sample was no UL94 grade.

[0139] Comparative Example 5 Polyamide PA6, aluminum diethylphosphinate, and a composite antioxidant were mixed at a weight ratio of 79.6:20:0.4 using a sealed mixer with a rotation speed of 50 rpm / min. The temperature was set to 260 °C, and after 5 minutes, it was taken out, cooled, and dried. Then, it was filled into a mold, preheated in a flat vulcanizer at 260 °C for 10 minutes, held at a pressure of 10 MPa for 5 minutes, and then cold-pressed. After cooling, samples were cut out and tested. The flame retardancy grade of the 1.6 mm sample was no UL94 grade.

[0140] JPEG2025521365000009.jpg62170

[0141] As can be seen from Examples 8-22, the flame retardant containing the dialkylphosphinic acid hybrid salt described in the present invention has excellent flame retardancy efficiency for polyamide. The prepared flame retardant PA66 has good toughness of the sample bar and no significant deterioration. In the combustion test of the flame retardant polyamide, there is no significant smoke. As can be seen from Comparative Examples 2-3, the dibutylphosphinate has a lower flame retardancy efficiency for polyamide than the hybrid salt having the formula (I) structure described in the present invention, and there is a lot of smoke when the flame retardant polyamide burns, which is disadvantageous for escape. Also, as can be seen from FIG. 1, its thermal stability is too low, the brittleness of the prepared flame retardant PA66 is large, and it shows deterioration. As can be seen from Comparative Examples 4-5, aluminum diethylphosphinate has a low flame retardancy efficiency for polyamide.

[0142] The above description is only some embodiments of the present invention and does not limit the present invention. Although the present invention has been disclosed in the above preferred embodiments, it does not limit the present invention. Within the scope of the technical means of the present invention, changes or modifications made by those skilled in the art based on the above technical content are equivalent to equivalent embodiments and are all included in the scope of the present invention.

Claims

1. A dialkylphosphinic acid hybrid salt, characterized by being at least one selected from compounds having a chemical formula represented by formula (I). (wherein M is a central atom, R １ , R ２ are each independently selected from C ４ -C １２ alkyl groups, and R １ , R ２ at least one of which is not an isobutyl group, Diethylphosphate ion, ethyl R １ Group phosphate ion, R １ Group R ２ Group phosphate ions are all ligands, M is selected from metal elements, and the metal element is at least one selected from Group IIA, IIIA, IVA, and VA metal elements, transition metal elements, and lanthanoid metal elements. n is the valence of the metal element M, and n is selected from 2, 3, or 4. Ethyl R １ phosphinate ion, diethylphosphinate ion, R １ group R ２ Among at least two kinds of acid ions of phosphinate ion of group R １ one is a phosphinate ion with a ligand coordinated to the central atom M being an ethyl R 0 ≦ x ≦ 0.76, 0.05 ≦ y ≦ 0.76, 0 ≦ z ≦ 0.76, and x + y + z = 1.

2. The Group IIA metal element is at least one selected from Be, Mg, Ca, Sr, and Ba. The Group IIIA metal element is Al. The Group IVA metal element is Sn. The Group VA metal element is Sb. The transition metal element is at least one selected from Fe, Zn, Cu, TI, Zr, and Mn. The lanthanoid metal element is Ce. The dialkylphosphinic acid hybrid salt according to claim 1.

3. The dialkylphosphinic acid hybrid salt according to claim 1, characterized in that 0 ≦ x ≦ 0.76, 0.05 ≦ y ≦ 0.67, and 0.005 ≦ z ≦ 0.

76.

4. 0 ≦ x ≦ 0.70, 0.05 ≦ y ≦ 0.67, 0.005 ≦ z ≦ 0.

70. Preferably, 0.1 ≦ x ≦ 0.65, 0.30 ≦ y ≦ 0.67, and 0.01 ≦ z ≦ 0.

50. Preferably, 0.30 ≦ x ≦ 0.65, 0.30 ≦ y ≦ 0.65, and 0.02 ≦ z ≦ 0.

40. The dialkylphosphinic acid hybrid salt according to claim 1.

5. The dialkylphosphinic acid hybrid salt according to claim 1, characterized in that M = Al and n = 3.

6. A method for preparing the dialkylphosphinic acid hybrid salt according to any one of claims 1 to 5, comprising the step of reacting mixture A with a raw material containing a metal element M source in an aqueous phase to carry out reaction I to obtain the dialkylphosphinic acid hybrid salt. The mixture A includes diethylphosphinic acid and / or its alkali metal salt, ethyl R １ group phosphinic acid and / or its alkali metal salt and R １ group R ２ group phosphinic acid and / or its alkali metal salt, and is characterized by a preparation method.

7. The preparation method according to claim 6, characterized in that the conditions of reaction I are a temperature of 0 - 250 °C, a pressure of 0.1 MPa - 10 MPa, and a time of 0.01 - 20 h.

8. The preparation method according to claim 6, characterized in that reaction I is carried out at a pH of 0 - 4.

9. The acquisition of mixture A An aqueous solution containing phosphinic acid and / or an alkali metal salt thereof and a free radical initiator is introduced with ethylene and C ４ -C １２ The preparation method according to claim 6, characterized by comprising the step of introducing an olefin, carrying out reaction II, and obtaining the mixture A.

10. The molar ratio of the phosphinic acid and / or its alkali metal salt, ethylene, C ４ -C １２ The olefin is 1:0.24 - 1.76:1.76 - 0.24, and the preparation method according to claim 9 is characterized in that

11. The preparation method according to claim 9, wherein in the aqueous solution, the mass of the water is 10-99% of the total mass of the aqueous solution.

12. The preparation method according to claim 9, wherein the conditions of the reaction II are a temperature of 0-250 °C, a time of 0.01-50 h, and a pressure of 0-3 MPa.

13. The molar ratio of the free radical initiator to the phosphinic acid and / or its alkali metal salt is 0.001-0.1:1, Preferably, the molar ratio of the free radical initiator to the phosphinic acid and / or its alkali metal salt is 0.003-0.05:

1. The preparation method according to claim 9 is characterized by this.

14. The acquisition of the mixture A is An aqueous solution containing phosphinic acid and / or an alkali metal salt thereof and a free radical initiator is introduced with C ４ -C １２ olefin, and after the molar ratio of the introduced C ４ -C １２ olefin to the total phosphorus of phosphinic acid and / or an alkali metal salt thereof reaches (y + 2z) / 1 in the formula (I), the introduction of C ４ -C １２ olefin is stopped, and ethylene is continuously introduced and reacted to obtain the mixture A. The preparation method according to claim 9, characterized by comprising the step.

15. The acquisition of the mixture A is An aqueous solution containing phosphinic acid and / or its alkali metal salt and a free radical initiator is introduced with C ４ -C １２ olefin and a part of ethylene to cause a reaction, and the molar ratio of ethylene to the total phosphorus of phosphinic acid and / or its alkali metal salt is less than (2x + y) / 1 of the formula (I). After the molar ratio of the introduced C ４ -C １２ olefin to the total phosphorus of phosphinic acid and / or its alkali metal salt reaches (y + 2z) / 1 of the formula (I), the introduction of C ４ -C １２ olefin is stopped, and the remaining ethylene is continuously introduced and reacted to obtain the mixture A. The preparation method according to claim 9, characterized by including this step.

16. The acquisition of the mixture A is Introduce a part of ethylene into an aqueous solution containing phosphinic acid and / or its alkali metal salt and a free radical initiator, and the molar ratio of the part of ethylene to the total phosphorus of phosphinic acid and / or its alkali metal salt is not more than (2x + y) / 1 of formula (I). After the part of ethylene has completely reacted, continue to introduce C ４ -C １２ olefin and react. After the molar ratio of the introduced C ４ -C １２ olefin to the total phosphorus of phosphinic acid and / or its alkali metal salt reaches (y + 2z) / 1 of formula (I), stop introducing C ４ -C １２ olefin, continue to introduce the remaining ethylene and react to obtain the mixture A. The preparation method according to claim 9, characterized by comprising the above steps.

17. The total amount of the ethylene and the C ４ -C １２ The preparation method according to any one of claims 9 to 16, characterized in that the molar ratio of the total amount of the olefin is 0.14 - 7.33:

1.

18. The metal element M source is at least one selected from salts of the metal element M, Preferably, the salt of the metal element M is at least one selected from nitrates, sulfates, hydrochlorides, acetates, and oxides of the metal element M. The preparation method according to claim 6 is characterized by this.

19. The flame retardant is at least one selected from the dialkylphosphinic acid hybrid salts according to any one of claims 1 to 5 and the dialkylphosphinic acid hybrid salts prepared by the method according to any one of claims 6 to 18. A flame retardant is characterized by this.

20. A flame retardant material comprising a flame retardant P and a thermoplastic polymer material, The flame retardant P is at least one selected from the flame retardants according to claim 19. A flame retardant material is characterized by this.

21. The flame retardant P is characterized in that the mass content in the flame retardant material is 1-35%. The flame retardant material according to claim 20 is characterized by this.

22. The flame retardant material further comprises a functional additive, The functional additive is at least one selected from a reinforcing agent, a drip inhibitor, a stabilizer, a pigment, a dye, a carbon formation catalyst, a dispersant, a nucleating agent, an inorganic filler, and an antioxidant, Preferably, the functional additive is characterized in that the mass content in the flame retardant material is 5-40%. The flame retardant material according to claim 20 is characterized by this.

23. The flame retardant material further comprises a flame retardant Q, The flame retardant Q is at least one selected from a nitrogen-based flame retardant and a boron-based flame retardant. The flame retardant material according to claim 22 is characterized by this.

24. The flame retardant Q is the flame retardant material according to claim 23, characterized in that the mass content in the flame retardant material is 0.5-20%.

25. The flame retardant material according to claim 20, characterized in that the thermoplastic polymer material is at least one selected from polyamide and polyester.

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