An organic phosphite, its preparation method and use

Abstract

The present invention discloses an organic phosphite, a preparation method and a use thereof. The synthesis method of the organic phosphite comprises the following steps: (1) dissolving a phosphorus source in water to obtain a solution with a concentration of 0.1-10 mol / L; (2) placing the solution into a reaction kettle, adding an olefin, and when the pressure rises to 0-10 MPa and the temperature rises to 10-200 °C, adding an auxiliary agent and turning on ultraviolet light to initiate the reaction. The reaction time is 0.1-100 h to obtain an organic phosphite solution or an organic phosphonic acid solution. The beneficial effects of the present invention are as follows: The present invention has a short reaction route and no waste acid or waste oxidant is generated; introducing a photoinitiation system enables the reaction of the system to be not limited by temperature and can react at a relatively low temperature. In addition, isoprene or acrylic acid is introduced into the olefin system. Isoprene can increase the number of free radicals in the gas phase, and acrylic acid can prolong the lifetime of free radicals in the aqueous phase and accelerate the reaction.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical substance preparation, and particularly relates to an organic phosphite, a preparation method thereof, and uses thereof. Background Art

[0002] At present, organic phosphoric acids are not easy to produce in batches. In particular, alkyl phosphorous acids have a long production process route and easily generate harmful waste, which requires a relatively high treatment cost. There are mainly two mainstream methods for organic phosphites. One is to synthesize an organic phosphoric acid ester from phosphorus trichloride and then obtain an organic phosphorous acid through hydrolysis. The organic phosphorous acid then reacts with metals, metal oxides, or metal hydroxides to obtain an organic phosphite. CN201711175795.X describes the use of dialkyl phosphites to be heated and hydrolyzed under acidic conditions to obtain alkyl phosphorous acids, which then react with metals or metal compounds to obtain alkyl phosphites. The other is to use an aqueous solution of sodium hypophosphite to react with alkenes to synthesize monoalkyl phosphinates, which are then oxidized and acidified with an oxidizing acid to obtain organic phosphorous acids, and then react with metal compounds to obtain organic phosphites. CN200980138621.3 describes the use of alkyl phosphinic acids and their salts to react with alkenes to obtain alkyl phosphinic acids and their salts or esters, which are then further oxidized to alkyl phosphoric acids and their salts or esters. These methods have high energy consumption during the synthesis process and generate waste such as waste acids and strong oxidants, making subsequent treatment and recycling difficult and costly.

[0003] To solve these problems, the present invention uses phosphorous acid and its salts as starting agents, with a relatively simple reaction process that does not produce excess waste acids or strong oxidants, and has simple post-treatment and low costs. Summary of the Invention

[0004] The present invention relates to the preparation and uses of an organic phosphite, which simplifies the synthesis process from inorganic phosphorus to organic phosphorus and reduces various wastes generated during production. Introducing a photoinitiator system enables the reaction in the system to be temperature-independent and can react at relatively low temperatures. In addition, isoprene or acrylic acid is introduced into the alkene system. Isoprene can increase the number of free radicals in the gas phase, and acrylic acid can extend the lifetime of free radicals in the aqueous phase, accelerating the reaction.

[0005] Specifically, an organic phosphite has the following structure:

[0006] (1)

[0007] Among them, M is a monovalent or divalent metal or ammonia. Specifically, M can be at least one of ammonia, sodium, magnesium, potassium, rubidium, and cesium; m is 1-2; x and y are positive integers, and m*x = 2*y; R1 is a C2-C18 saturated alkyl group, or a C3-C18 cycloalkyl group with at least one ring, or a C7-C18 aralkyl group and its isomeric organic functional groups. Specifically, it can be one of ethyl, propyl, butyl, pentyl, hexyl, octyl, cyclopropyl, cyclobutyl, cyclohexyl, cyclopropylethyl, phenylethyl, phenylpropyl, and phenylbutyl.

[0008] In order to better achieve the above-mentioned invention purpose, the present invention also provides a method for synthesizing an organic phosphite, comprising the following steps:

[0009] (1) Dissolve the phosphorus source in water to obtain a phosphorus source solution with a concentration of 0.1-10 mol / L; among them, the concentration is preferably 0.5-5 mol / L;

[0010] (2) Place the phosphorus source solution in a reaction kettle, add an olefin. When the pressure rises to 0-10 MPa (preferably 0-5 Mpa) and the temperature rises to 10-200 °C (preferably 50-150 °C), add an auxiliary agent and turn on ultraviolet light to initiate the reaction. The reaction time is 0.1-100 h (preferably 1-50 h) to obtain an organic phosphite solution or an organic phosphonic acid solution;

[0011] Among them, the phosphorus source is phosphorous acid or a soluble phosphite, specifically, it can be sodium phosphite, potassium phosphite, lithium phosphite, or ammonium phosphite; the auxiliary agent includes a photoinitiator, and isoprene and / or acrylic acid; the addition amount of isoprene and / or acrylic acid is 0.1%-1% of the amount of substance of the phosphorus source (that is, the molar ratio of isoprene and / or acrylic acid to the phosphorus source is 0.1%-1%).

[0012] Preferably, the olefin is a C2-C18 aliphatic monoolefin, or a C3-C18 olefin with at least one ring, or a C7-C18 aromatic olefin; the olefin is one, two, or more of ethylene, propylene, butene, pentene, hexene, octene, decene, hexadecene, octadecene, cyclopropene, cyclobutene, cyclohexene, cyclopropylethylene, cyclobutylethylene, cyclopentylethylene, cyclohexylethylene, styrene, phenylpropylene, phenylbutene, and isomers of its olefins; further preferably, one, two, or more of ethylene, propylene, butene, pentene, hexene, octene, cyclopropene, cyclobutene, cyclohexene, cyclopropylethylene, styrene, phenylpropylene, phenylbutene, and isomers of its olefins.

[0013] Preferably, the photoinitiator is a UV photoinitiator; the UV initiator is one, two or more of 2-hydroxy-2-methyl-1-phenylpropanone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-2-(4-morpholinyl)-1-[4-(methylthio)phenyl]-1-propanone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, ethyl 2,4,6-trimethylbenzoyl phenylphosphinate, 2-dimethylamino-2-benzyl-1-[4-(4-morpholinyl)phenyl]-1-butanone, 2-hydroxy-2-methyl-1-phenylpropanone, 2-hydroxy-2-methyl-1-[4-(2-hydroxyethoxy)phenyl]-1-propanone, methyl benzoylformate, acetone and hydrogen peroxide.

[0014] The present invention also provides an organic phosphite metal salt, which is obtained by adding an alkali solution, or a metal hydroxide, or a metal oxide, or a metal to the above-mentioned organic phosphite salt solution or the organic phosphite salt solution obtained by the above synthesis process and reacting.

[0015] The use of the above-mentioned organic phosphite metal salt of the present invention for preparing a flame retardant; wherein, the preparation of the flame retardant is specifically as follows:

[0016] Adding a divalent to tetravalent metal salt solution to the above-mentioned organic phosphite metal salt solution to carry out a metathesis reaction to obtain a phosphorus-based flame retardant; or,

[0017] First, mix the above-mentioned organic phosphite metal salt with other organic phosphite salt solutions or organic hypophosphite salt solutions, and then react with a divalent to tetravalent metal salt solution to form a mixed salt flame retardant.

[0018] Wherein, the metal salt is one, two or more of aluminum sulfate and its hydrates, lanthanum sulfate and its hydrates, manganese sulfate and its hydrates.

[0019] Preferably, the above-mentioned flame retardant prepared from the organic phosphite metal salt of the present invention has the following structural formula:

[0020] (Ⅱ)

[0021] Or,

[0022] (Ⅲ)

[0023] Among them, N is a divalent to tetravalent metal element; n is 2 - 4, n×a = 2b, c and d are positive numbers not less than 0.01 and not greater than 10; e is a positive number between 1 and 10, and n×e = c + 2d; R1, R2, and R3 can be the same or different, and are each independently selected from saturated alkyl groups having 2 to 18 carbon atoms, cycloalkyl groups having at least one ring and 3 to 18 carbon atoms, aralkyl groups having 7 to 18 carbon atoms, and their isomeric organic functional groups; preferably, R2 and R3 are each independently selected from ethyl, propyl, butyl, pentyl, hexyl, octyl, cyclopropyl, cyclobutyl, cyclohexyl, cyclopropylethyl, phenethyl, phenylpropyl, phenylbutyl, and their isomers.

[0024] The present invention also provides a flame - retardant system containing the above - mentioned flame retardant. The system includes: 30 - 95 wt% of a polymer substrate, 0 - 50 wt% of a fiber - reinforcing material, 5 - 30 wt% of a flame retardant, and 0 - 10 wt% of an additive; wherein, the flame retardant herein is the flame retardant synthesized in the present invention; preferably, the polymer can be a polyurethane resin, a polyester resin, or a polyamide resin, the fiber - reinforcing material is preferably long or short fibers of glass fiber, carbon fiber, or basalt fiber, and the additive can be a color masterbatch, a masterbatch powder, a lubricant, a mold release agent, a toughening agent, a solubilizing agent, a conductive agent, a water - repellent agent, or an ant - termite agent.

[0025] The beneficial effects of the present invention are as follows: Compared with acid - hydrolyzed organophosphoric esters or oxidized mono - alkyl phosphinates, the present invention has a short reaction route and does not produce waste acid or waste oxidant; introducing a photo - initiation system enables the reaction of the system to be temperature - independent and can react at a relatively low temperature. In addition, isoprene or acrylic acid is introduced into the olefin system. Isoprene can increase the number of free radicals in the gas phase, and acrylic acid can extend the lifetime of free radicals in the aqueous phase and accelerate the reaction. Detailed Embodiments

[0026] To clearly illustrate the technical features of the present solution, the present solution will be elaborated below through specific embodiments.

[0027] Example 1

[0028] Sodium phosphite is dissolved in deionized water to form a 1 mol / L aqueous solution, which is added to a stainless - steel reaction kettle that has been purged with nitrogen three times in advance. When the temperature is raised to 50°C, ethylene is added to the reaction kettle. When the pressure reaches 1 MPa, 0.1% mol of isoprene based on the amount of substance of sodium phosphite is added, and then a 1% - concentration hydrogen peroxide solution is slowly dropped in, and then the UV lamp is turned on to initiate the reaction. During the reaction process, the reaction pressure is always maintained at 0.9 - 1 MPa, the reaction time is 15 h. After the reaction is completed, ethylene is evacuated, the product is discharged and filtered; through nuclear magnetic resonance phosphorus spectrum testing, the composition of the synthesized product is as follows:

[0029] Sodium ethyl phosphate: 99 mol%;

[0030] Sodium phosphite: 0.5 mol%;

[0031] Unknown component: 05 mol.

[0032] Example 2

[0033] Ammonium phosphite was dissolved in deionized water to form an aqueous solution with a concentration of 0.5 mol / L, and it was added to a stainless steel reactor that had been purged with nitrogen three times in advance. When the temperature was raised to 50 °C, ethylene was added to the reactor. When the ethylene pressure reached 5 MPa, 0.2 mol% of isoprene based on the amount of ammonium phosphite and 0.2 mol% of acrylic acid based on the amount of ammonium phosphite were added. Then, a 1% hydrogen peroxide aqueous solution was slowly dropped in, and then the UV lamp was turned on to initiate the reaction. During the reaction, the reaction pressure was always maintained at 4.9 - 5 MPa, and the reaction time was 2 h. After the reaction ended, the ethylene was evacuated, the product was discharged and filtered. After testing the phosphorus spectrum by nuclear magnetic resonance, the composition of the synthesized product was as follows:

[0034] Ammonium ethylphosphonite: 97 mol%;

[0035] Ammonium phosphite: 2 mol%;

[0036] Unknown component: 1 mol%.

[0037] Example 3

[0038] Potassium phosphite was dissolved in deionized water to form an aqueous solution with a concentration of 2 mol / L, and it was added to a stainless steel reactor that had been purged with nitrogen three times in advance. When the temperature was raised to 80 °C, ethylene was added to the reactor. When the ethylene pressure reached 10 MPa, 0.3 mol% of isoprene based on the amount of potassium phosphite was added. Then, a 1% hydrogen peroxide aqueous solution was slowly dropped in, and then the UV lamp was turned on to initiate the reaction. During the reaction, the reaction pressure was always maintained at 9.9 - 10 MPa, and the reaction time was 10 min. After the reaction ended, the ethylene was evacuated, the product was discharged and filtered. After testing the phosphorus spectrum by nuclear magnetic resonance, the composition of the synthesized product was as follows:

[0039] Potassium ethylphosphonite: 97 mol%;

[0040] Potassium phosphite: 2.5 mol%;

[0041] Unknown component: 0.5 mol%.

[0042] Example 4

[0043] Lithium phosphite was dissolved in deionized water to form an aqueous solution with a concentration of 5 mol / L, and it was added to a stainless-steel reactor that had been purged with nitrogen three times in advance. When the temperature was raised to 40 °C, ethylene was added to the reactor. When the ethylene pressure reached 10 MPa, isoprene with a molar amount of 0.2 mol% of lithium phosphite was added, and then an acetone solution of 2-hydroxy-2-methyl-1-phenylpropanone with a concentration of 1% and a molar amount of 0.001 mol% of lithium phosphite was added. Then, hydrogen peroxide with a concentration of 1% was slowly added dropwise, and at the same time, the UV lamp was turned on to initiate the reaction. During the reaction process, the reaction pressure was always maintained at 9.9 - 10 MPa, and the reaction time was 30 min. After the reaction ended, ethylene was evacuated, the product was discharged and filtered, and the phosphorus spectrum was tested by nuclear magnetic resonance. The composition of the synthesized product is as follows:

[0044] Lithium ethylphosphonite: 99.7 mol%;

[0045] Lithium phosphite: 0 mol%;

[0046] Unknown component: 0.3 mol%.

[0047] Example 5

[0048] Ammonium phosphite was dissolved in deionized water to form an aqueous solution with a concentration of 0.5 mol / L, and it was added to a stainless-steel reactor that had been purged with nitrogen three times in advance. When the temperature was raised to 80 °C, ethylene was added to the reactor. When the ethylene pressure reached 0.5 MPa, acrylic acid with a molar amount of 0.2 mol% of ammonium phosphite was added, and then 2,4,6-trimethylbenzoyl-diphenylphosphine oxide with a molar amount of 0.001 mol% of ammonium phosphite was added. Then, hydrogen peroxide with a concentration of 1% was slowly added dropwise, and the UV lamp was turned on to initiate the reaction. During the reaction process, the reaction pressure was always maintained at 0.4 - 0.5 MPa, and the reaction time was 50 h. After the reaction ended, ethylene was evacuated, the product was discharged and filtered, and the phosphorus spectrum was tested by nuclear magnetic resonance. The composition of the synthesized product is as follows:

[0049] Ammonium ethylphosphonite: 99.99 mol%;

[0050] Ammonium phosphite: 0 mol%;

[0051] Unknown component: 0.01 mol%.

[0052] Example 6

[0053] Dissolve ammonium phosphite in deionized water to form an aqueous solution with a concentration of 0.5 mol / L, and add it to a stainless steel reaction kettle that has been purged with nitrogen three times in advance. When the temperature is raised to 80 °C, add propylene to the reaction kettle. When the propylene pressure reaches 0.5 MPa, add 0.5% mol of isoprene based on the amount of sodium phosphite, and then add 0.002 mol% of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide based on the amount of ammonium phosphite. Then, slowly dropwise add hydrogen peroxide with a concentration of 1%, and turn on the UV lamp to initiate the reaction. During the reaction process, always maintain the reaction pressure at 0.4 - 0.5 MPa, and the reaction time is 40 h. After the reaction is completed, evacuate the propylene, discharge the product and filter it. After testing the phosphorus spectrum by nuclear magnetic resonance, the composition of the synthesized product is as follows:

[0054] Ammonium propylphosphonite: 99.99 mol%;

[0055] Ammonium phosphite: 0 mol%;

[0056] Unknown component: 0.01 mol%.

[0057] Example 7

[0058] Dissolve ammonium phosphite in deionized water to form an aqueous solution with a concentration of 0.5 mol / L, and add it to a stainless steel reaction kettle that has been purged with nitrogen three times in advance. Add 0.1 mol% of acrylic acid based on the amount of ammonium phosphite. When the temperature is raised to 80 °C, add butene to the reaction kettle. When the butene pressure reaches 0.5 MPa, then add 0.002 mol% of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide based on the amount of ammonium phosphite. Then, slowly dropwise add hydrogen peroxide with a concentration of 1%, and turn on the UV lamp to initiate the reaction. During the reaction process, always maintain the reaction pressure at 0.4 - 0.5 MPa, and the reaction time is 40 h. After the reaction is completed, evacuate the butene, discharge the product and filter it. After testing the phosphorus spectrum by nuclear magnetic resonance, the composition of the synthesized product is as follows:

[0059] Ammonium butylphosphonite: 99.99 mol%;

[0060] Ammonium phosphite: 0 mol%;

[0061] Unknown component: 0.01 mol%.

[0062] Example 8

[0063] Dissolve ammonium phosphite in deionized water to form an aqueous solution with a concentration of 0.5 mol / L, and add it to a stainless-steel reaction kettle that has been purged with nitrogen three times in advance. When the temperature is raised to 80 °C, add butene to the reaction kettle. When the pressure of butene reaches 0.2 MPa, add acrylic acid with a molar amount of 1% of ammonium phosphite, and then add 2,4,6-trimethylbenzoyl-diphenylphosphine oxide with a molar amount of 0.002 mol% of ammonium phosphite. Then, slowly drip hydrogen peroxide with a concentration of 1% and turn on the UV lamp to initiate the reaction. During the reaction process, always maintain the reaction pressure at 0.1 - 0.2 MPa, and the reaction time is 50 h. After the reaction is completed, evacuate butene, discharge the product and filter it. After testing the phosphorus spectrum by nuclear magnetic resonance, the composition of the synthesized product is as follows:

[0064] Ammonium butylphosphite: 98 mol%;

[0065] Ammonium phosphite: 1 mol%;

[0066] Unknown component: 1 mol%.

[0067] Example 9

[0068] Dissolve ammonium phosphite in deionized water to form an aqueous solution with a concentration of 0.5 mol / L, and add it to a stainless-steel reaction kettle that has been purged with nitrogen three times in advance. When the temperature is raised to 50 °C, add 2-butene to the reaction kettle. When the pressure of 2-butene reaches 2 MPa, add isoprene with a molar amount of 0.2% of ammonium phosphite, and then add the acetone solution of 2-hydroxy-2-methyl-1-phenylpropanone with a molar amount of 0.005 mol% of ammonium phosphite in batches, and slowly drip 1% hydrogen peroxide solution. Turn on the UV ultraviolet light for catalytic reaction. During the reaction process, always maintain the reaction pressure at 1.8 - 2 MPa, and the reaction time is 20 h. After the reaction is completed, evacuate 2-butene, discharge the product and filter it. After testing the phosphorus spectrum by nuclear magnetic resonance, the composition of the synthesized product is as follows:

[0069] Ammonium isobutylphosphite: 99.9 mol%;

[0070] Ammonium phosphite: 0 mol%;

[0071] Unknown component: 0.1 mol%.

[0072] Example 10

[0073] Dissolve sodium phosphite in deionized water to form a 2 mol / L aqueous solution, and add it to a stainless steel reaction kettle that has been purged with nitrogen three times in advance. When the temperature is raised to 100 °C, add ethylene to the reaction kettle. When the ethylene pressure reaches 6 MPa, add 0.2% mol of acrylic acid based on the amount of sodium phosphite and 0.3% mol of isoprene based on the amount of sodium phosphite. Then, add 0.008 mol% of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide in ammonium phosphite in batches, and slowly dropwise add 3% hydrogen peroxide solution, and turn on the UV ultraviolet photocatalytic reaction. During the reaction process, always keep the reaction pressure at 5.8 - 6 MPa, the reaction time is 40 h. After the reaction is completed, evacuate the ethylene, discharge the product and filter it. After testing the phosphorus spectrum by nuclear magnetic resonance, the composition of the synthesized product is as follows:

[0074] Sodium ethylphosphite: 99.9 mol%;

[0075] Ammonium phosphite: 0 mol%;

[0076] Unknown component: 0.1 mol%.

[0077] Example 11

[0078] Dissolve sodium phosphite in deionized water to form a 2 mol / L aqueous solution, and add it to a stainless steel reaction kettle that has been purged with nitrogen three times in advance. When the temperature is raised to 60 °C, add ethylene to the reaction kettle. When the ethylene pressure reaches 4 MPa, add 0.1% mol of acrylic acid based on the amount of sodium phosphite and 0.3% mol of isoprene based on the amount of sodium phosphite. Then, add 1% hydrogen peroxide and acetone in batches, and turn on the UV ultraviolet photocatalytic reaction. During the reaction process, always keep the reaction pressure at 3.8 - 4 MPa, the reaction time is 40 h. After the reaction is completed, evacuate the ethylene, discharge the product and filter it. After testing the phosphorus spectrum by nuclear magnetic resonance, the composition of the synthesized product is as follows:

[0079] Ammonium ethylphosphite: 99.9 mol%;

[0080] Ammonium phosphite: 0 mol%;

[0081] Unknown component: 0.1 mol%.

[0082] Example 12

[0083] Dissolve phosphorous acid in deionized water to form a 2 mol / L aqueous solution, and add it to a stainless-steel reactor that has been purged with nitrogen three times in advance. When the temperature is raised to 100 °C, add ethylene to the reactor. When the ethylene pressure reaches 6 MPa, add 0.1% mol of acrylic acid based on the amount of phosphorous acid and 0.4% mol of isoprene based on the amount of phosphorous acid, then add 2,4,6-trimethylbenzoyl-diphenylphosphine oxide and acetone in batches, and add 1% hydrogen peroxide solution. Turn on the UV ultraviolet light catalytic reaction. During the reaction, always maintain the reaction pressure at 5.8 - 6 MPa, and the reaction time is 40 h. After the reaction is completed, evacuate the ethylene, discharge the product, filter it, neutralize it with ammonia water, and test the phosphorus spectrum by nuclear magnetic resonance. The composition of the synthesized product is as follows:

[0084] Ethyl phosphonous acid: 99.9 mol%;

[0085] Phosphorous acid: 0 mol%;

[0086] Unknown component: 0.1 mol%.

[0087] Then add a divalent metal hydroxide solution, or a divalent metal, or a divalent metal oxide to the obtained ethyl phosphonous acid solution to react to obtain the corresponding ethyl phosphite.

[0088] Example 13

[0089] Dissolve sodium phosphite in deionized water to form a 1 mol / L aqueous solution, and add it to a stainless-steel reactor that has been purged with nitrogen three times in advance. When the temperature is raised to 50 °C, add ethylene to the reactor. When the ethylene pressure reaches 1 MPa, add 0.1% mol of acrylic acid based on the amount of sodium phosphite and 0.5% mol of isoprene based on the amount of sodium phosphite, then slowly drop in a 1% hydrogen peroxide solution. During the reaction, always maintain the reaction pressure at 0.9 - 1 MPa, and the reaction time is 15 h. After the reaction is completed, evacuate the ethylene, discharge the product, and filter it; test the phosphorus spectrum by nuclear magnetic resonance. The composition of the synthesized product is as follows:

[0090] Sodium ethyl phosphonite: 80 mol%;

[0091] Sodium phosphite: 19 mol%;

[0092] Unknown component: 1 mol%.

[0093] Example 14

[0094] Dissolve ammonium phosphite in deionized water to form a 5 mol / L aqueous solution, and add it to a stainless steel reactor that has been purged with nitrogen three times in advance. When the temperature is raised to 80 °C, add ethylene to the reactor. When the ethylene pressure reaches 4 MPa, add 0.2% mol of acrylic acid based on the amount of ammonium phosphite and 0.2% mol of isoprene based on the amount of sodium phosphite, and then slowly dropwise add an acetone solution of 2,4,6-trimethylbenzoyl diphenylphosphate with a concentration of 1%. During the reaction process, always maintain the reaction pressure at 3.9 - 4.1 MPa, and the reaction time is 30 min. After the reaction, evacuate ethylene, discharge the product and filter it. After testing the phosphorus spectrum by nuclear magnetic resonance, the composition of the synthesized product is as follows:

[0095] Ammonium ethylphosphonite: 99.7 mol%;

[0096] Phosphorous acid: 0 mol%;

[0097] Unknown component: 0.3 mol%.

[0098] Example 15

[0099] Add a 2 - 4 valent metal salt solution to each organic phosphite metal salt solution in Example 14 to carry out a metathesis reaction, and a phosphorus-based flame retardant can be obtained; or,

[0100] First mix each organic phosphite metal salt in Example 14 with other organic phosphonate solutions, and then react with a 2 - 4 valent metal salt solution to form a mixed salt flame retardant; among them, the other organic phosphonate solutions can be: dialkyl phosphinate solutions or monoalkyl phosphinate solutions;

[0101] Among them, the metal salt can be one, two or more of aluminum sulfate and its hydrates, lanthanum sulfate and its hydrates, manganese sulfate and its hydrates.

[0102] Example 16

[0103] This example provides a flame retardant system containing any one of the flame retardants in Example 15 above. The system includes: 60 wt% of polymer substrate, 20 wt% of fiber reinforcing material, 15 wt% of flame retardant, and 5 wt% of additive;

[0104] Among them, the polymer can be polyurethane resin, polyester resin, polyamide resin, the fiber reinforcing material is glass fiber, and the additive can be color masterbatch, masterbatch powder, lubricant, mold release agent, toughening agent, solubilizer, conductive agent, water repellent, ant repellent.

[0105] Comparative Example 1

[0106] Use 2 mol of DEEP (diethyl ethylphosphonate) and place it in a 2 L flask. Then add 500 ml of 2 mol / L sulfuric acid. Heat it up to 110 °C and reflux for 48 hours. Distill the product under reduced pressure to obtain the target product. After testing the carbon spectrum by nuclear magnetic resonance, the composition of the synthesized product is as follows:

[0107] Ethylphosphonic acid: 60 mol%;

[0108] Monoethyl ethylphosphonate: 40 mol%.

[0109] Through such a reaction, the content of ethylphosphonic acid obtained is relatively low, and there is residual sulfuric acid that needs to be treated. The process of distillation under reduced pressure easily causes the target product to be oxidized and turn yellow.

[0110] Comparative Example 2

[0111] Place 2 mol of DEEP (diethyl ethylphosphonate) in a 2 L flask, add 550 ml of 4 mol / L sodium hydroxide solution, heat it up to 110 °C and reflux for 48 hours. Neutralize the product with sulfuric acid to obtain an aqueous solution of the target product. After testing the hydrogen spectrum and carbon spectrum of this product by nuclear magnetic resonance, the composition of the synthesized product is as follows:

[0112] Sodium ethylphosphonate: 80 mol%;

[0113] Sodium monoethyl ethylphosphonate: 20 mol%;

[0114] There is still excessive alkali in the sodium ethylphosphonate synthesized by this method. After neutralization, there will be excess salt generated, which is mixed in the sodium ethylphosphonate and has a lower purity and is not easy to separate.

[0115] Comparative Example 3

[0116] Put 2000 L of 1 mol / L hypophosphorous acid solution into a 5 L reaction kettle lined with enamel. After purging with nitrogen 3 times, introduce ethylene. When the pressure reaches 1 MPa and the temperature rises to 80 °C, add a sodium persulfate solution. Stop the reaction when about 1 mol of ethylene is consumed, evacuate the ethylene, and then acidify and oxidize the product with 10 mol of concentrated nitric acid for 10 hours to obtain an ethylphosphonic acid solution. Since there is a large amount of residual nitric acid in the solution, at this time, distill the nitric acid and then dissolve it to obtain the by-product dilute nitric acid and a sodium ethylphosphonate solution. After testing the phosphorus spectrum, carbon spectrum and hydrogen spectrum by nuclear magnetic resonance, the composition of the synthesized product is as follows:

[0117] Sodium ethylphosphonate: 50 mol%;

[0118] Sodium diethylphosphinate: 25 mol%;

[0119] Sodium phosphate: 25 mol%.

[0120] When synthesizing with this method, it is necessary to process the remaining nitric acid. The treatment process is complex, there are many impurities, the overall purity is poor, and it is not easy to industrialize.

[0121] It can be seen from the above Comparative Examples 1-3 that the content of organic phosphonous acid / organic phosphonite in the synthesis product is low, the quality is low, there are many impurities, and the treatment process is rather complex. In the synthesis product of the present invention, the active ingredient reaches more than 99%, and the process route is short, which is very suitable for industrialization.

[0122] Comparative Example 4

[0123] Dissolve potassium phosphite in deionized water to form an aqueous solution with a concentration of 2 mol / L, and add it to a stainless steel reaction kettle that has been purged with nitrogen three times in advance. When the temperature is raised to 80 °C, add ethylene to the reaction kettle. When the ethylene pressure reaches 10 MPa, slowly drop a mixed solution of 1% hydrogen peroxide solution and 0.02% ferrous sulfite solution, and then turn on the UV lamp to initiate the reaction. During the reaction, the reaction pressure is always maintained at 9.9-10 MPa, the reaction time is 20 h. After the reaction is completed, evacuate the ethylene, discharge the product and filter it. After testing the phosphorus spectrum by nuclear magnetic resonance, the composition of the synthesized product is as follows:

[0124] Potassium ethylphosphate: 87 mol%;

[0125] Potassium phosphite: 12.5 mol%;

[0126] Unknown potassium compound: 0.5 mol%.

[0127] It can be seen from the above Comparative Examples 1-3 that the content of organic phosphonous acid / organic phosphonite in the synthesis product is low, the quality is low, there are many impurities, and the treatment process is rather complex. It can be seen from Comparative Example 4 that when using ethylene alone, even when the pressure reaches 10 MPa, the reaction temperature reaches 80 °C and the reaction time reaches 20 hours, the product purity is only 87 mol%, and 12.5 mol% is still unreacted. In the synthesis product of the present invention, the active ingredient reaches more than 99%, and the process route is short, which is very suitable for industrialization.

[0128] Test experiment

[0129] In order to verify that the organic phosphonite of the present invention can be used for the synthesis of flame retardants and has a good flame retardant effect, we conducted the following test experiments; specifically as follows:

[0130] Experiment 1: Take 1 L of the sodium ethyl phosphate solution synthesized in Example 1, and dilute it to a concentration of 0.5 mol / L. Add 2 L of the sodium diethyl phosphinate solution with a concentration of 0.5 mol / L. After mixing evenly, add dropwise 1.34 L of the aluminum sulfate solution with a concentration of 0.5 mol / L. The addition is completed within 2 hours. After the addition is completed, stir for 3 hours. Keep the temperature constant at 50 °C throughout the process. After stirring, filter the mixture, wash, dry, and pulverize it to obtain the flame retardant ADEP, denoted as ADEP-1;

[0131] Experiment 2: Except that the organic phosphite is changed to the ammonium ethyl phosphite solution synthesized in Example 2, the implementation process is the same as that in Experiment 1 to synthesize ADEP, denoted as ADEP-2;

[0132] Experiment 3: Except that the organic phosphite is changed to the lithium ethyl phosphite solution synthesized in Example 4, the implementation process is the same as that in Experiment 1 to synthesize ADEP, denoted as ADEP-3;

[0133] Experiment 4: Except that the organic phosphite is changed to the ammonium isobutyl phosphite solution synthesized in Example 9, the implementation process is the same as that in Experiment 1 to synthesize ADEP, denoted as ADEP-4;

[0134] Experiment 5: Take the sodium ethyl phosphate solution synthesized in Example 10, dilute it to 1 mol / L, and react it with the aluminum sulfate solution with a concentration of 0.22 mol / L. Filter, wash, dry, and pulverize it to obtain aluminum ethyl phosphonate, denoted as ADEP-5;

[0135] Experiment 6: Take the sodium ethyl phosphate solution synthesized in Example 10, dilute it to 1 mol / L, and react it with the lanthanum sulfate solution with a concentration of 0.22 mol / L. Filter, wash, dry, and pulverize it to obtain lanthanum ethyl phosphonate, denoted as ADEP-6;

[0136] Experiment 7: Take the sodium ethyl phosphate solution synthesized in Example 10, dilute it to 1 mol / L, and react it with the iron sulfate solution with a concentration of 0.22 mol / L. Filter, wash, dry, and pulverize it to obtain iron ethyl phosphonate, denoted as ADEP-7.

[0137] Test the metal organic phosphites obtained in the above Experiments 1-7 according to the ratio shown in Table 1. The test process is as follows:

[0138] i) Place the raw materials in a vacuum oven at 80 °C and bake for 8 hours to remove excess free moisture;

[0139] ii) After placing the dried raw materials in a high-speed mixer and mixing evenly, use a twin-screw extruder to extrude and pelletize;

[0140] iii) Place the prepared particles in a vacuum oven at 80 °C and bake for 8 hours, then perform injection molding to produce test specimens: 3 mm dumbbell-shaped tensile strength test specimens and 1.6 mm flame retardant strips for testing.

[0141] iv) Place the specimens in an environment with a temperature of 23 ± 2 °C and a humidity of 50% ± 10% for 48 hours before testing; the test results are shown in Table 2.

[0142] Table 1 Raw material ratio of test experimental materials

[0143]

[0144] Table 2 Test experimental performance

[0145]

[0146] It can be seen from Table 2 that the alkyl phosphite synthesized by the present invention can have good flame retardant properties in the glass fiber reinforced PA-66 flame retardant system, and only 15% addition amount can achieve UL94-V0@1.6mm. It can also be used in combination with melamine polyphosphate, and only 15% of the total amount of flame retardant can be added to achieve UL94-V0@1.6mm, and the raw material cost can be reduced.

[0147] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for synthesizing an organic phosphite, characterized in that, The method comprises the following steps: (1) Dissolve a phosphorus source in water to obtain a phosphorus source solution with a concentration of 0.1 - 10 mol / L; (2) Place the phosphorus source solution in a reaction kettle, add an olefin, after the pressure rises to 0 - 10 MPa and the temperature rises to 10 - 200 °C, add an auxiliary agent and turn on ultraviolet light to initiate the reaction, and the reaction time is 0.1 - 100 h to obtain an organic phosphite solution or an organic phosphonic acid solution; The phosphorus source is phosphorous acid or a soluble phosphite; the auxiliary agent includes a photoinitiator, and isoprene and / or acrylic acid; the addition amount of isoprene and / or acrylic acid is 0.1% - 1% of the amount of substance of the phosphorus source; The photoinitiator is a UV photoinitiator; the UV initiator is ethyl 2,4,6 - trimethylbenzoyl phenylphosphinate, or hydrogen peroxide, or Acetone is used in combination with any one of methyl benzoylformate, 2,4,6 - trimethylbenzoyl - diphenylphosphine oxide, ethyl 2,4,6 - trimethylbenzoyl phenylphosphinate and hydrogen peroxide; or Any one of 2 - hydroxy - 2 - methyl - 1 - phenylpropanone, 1 - hydroxycyclohexyl phenyl ketone, 2 - methyl - 2 - (4 - morpholinyl) - 1 - [4 - (methylthio)phenyl] - 1 - butanone, 2 - dimethylamino - 2 - benzyl - 1 - [4 - (4 - morpholinyl)phenyl] - 1 - butanone, 2 - hydroxy - 2 - methyl - 1 - phenylpropanone, 2 - hydroxy - 2 - methyl - 1 - [4 - (2 - hydroxyethoxy)phenyl] - 1 - propanone, acetone is used in combination with any one of methyl benzoylformate, 2,4,6 - trimethylbenzoyl - diphenylphosphine oxide, ethyl 2,4,6 - trimethylbenzoyl phenylphosphinate and hydrogen peroxide.

2. The method according to claim 1, wherein The olefin is an aliphatic olefin with C2 - C18, or an olefin with at least one ring and C3 - C18, or an aromatic olefin with C7 - C18.

Images