Preparation method and application of phenethyl bridged DOPO derivative

Abstract

The invention relates to a preparation method and application of a phenethyl bridged DOPO derivative, and the preparation method comprises the following steps: uniformly mixing a bridged substrate, DOPO and an acidic catalyst, heating to a temperature T, carrying out a heat preservation reaction for a time t, and carrying out post-treatment to obtain the phenethyl bridged DOPO derivative, according to the application, the phenethyl bridged DOPO derivative and polyester are subjected to melt blending to prepare flame-retardant master batches, then the master batches are added into polyester chips or melt direct spinning, and the flame-retardant polyester fiber is prepared after drafting and winding. The preparation method provided by the invention has the advantages of low equipment requirement, no use of volatile acid and reaction solvent, simple process, easy post-treatment, high product yield, wide and easily available raw materials and easy industrial production, and overcomes the defects of the existing preparation method. The flame-retardant polyester fiber prepared from the derivative is colorless, transparent, high in strength and good in elongation at break and flame retardance.

Description

Technical Field

[0001] The invention belongs to the technical field of flame retardants, and particularly relates to a preparation method and application of a phenethyl bridged DOPO derivative. Background Art

[0002] In the 1970s, Sanko Chemical Industry Co., Ltd. published a patent and disclosed the synthesis method of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO). Since then, DOPO has been used as a raw material to synthesize various organophosphorus compounds. In particular, the research on halogen-free flame retardants has received more and more attention in recent years. As a new type of phosphorus-containing flame retardant, DOPO and its derivatives can play a flame retardant role in both the gas phase and the condensed phase, so they are considered to be one of the powerful substitutes for halogen flame retardants.

[0003] Bridged DOPO is an important type of DOPO derivative, and has good flame retardant properties and physical and chemical properties. For example, patent WO2010135398 discloses a vinyl-bridged DOPO derivative, but it does not include aromatic-substituted vinyl-bridged derivatives, and its thermal stability needs to be further improved.

[0004] In order to overcome the above problems, patent CN104086593B discloses a class of DOPO derivatives, preparation methods and applications thereof, using aromatic ketones and DOPO compounds as raw materials to prepare aromatic-substituted vinyl-bridged DOPO derivatives in a solvent under the action of an acidic catalyst. However, the preparation method of the DOPO derivatives has a long reaction time, usually greater than 24 hours, which is not conducive to large-scale production and application.

[0005] Therefore, it is particularly important to adopt another chemical route to conveniently and efficiently prepare this type of phenethyl-bridged DOPO derivatives. Summary of the invention

[0006] The present invention aims to solve the problems in the prior art and provides a preparation method and application of a phenethyl bridged DOPO derivative.

[0007] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] A method for preparing a phenethyl bridged DOPO derivative, comprising uniformly mixing a bridged substrate, DOPO and an acidic catalyst, heating the mixture to a temperature T and then keeping the mixture warm for a reaction time t, and performing post-treatment (pouring out while hot, cooling naturally, crushing, and washing with water, a C1-C6 fatty alcohol or a mixture thereof until neutral) to obtain a phenethyl bridged DOPO derivative, wherein the molar ratio of DOPO to the bridged substrate is 2 to 3.5:1;

[0009] The bridging substrate is The temperature T is 140-170°C, and the duration t is 2-4h;

[0010] Alternatively, the bridging substrate is The temperature T is 140-170°C, and the duration t is 4-8h;

[0011] Alternatively, the bridging substrate is The temperature T is 50-80°C, and the duration t is 0.5-2h;

[0012] Alternatively, the bridging substrate is The temperature T is 140-170°C, and the duration t is 2-4h;

[0013] Alternatively, the bridging substrate is The temperature T is 140-170°C, and the time t is 1-4h.

[0014] As the preferred technical solution:

[0015] In the method for preparing a phenethyl bridged DOPO derivative as described above, the molar ratio of DOPO to the acidic catalyst is 1:0.1-2.

[0016] The method for preparing a phenethyl bridged DOPO derivative as described above, wherein the acidic catalyst is an aqueous solution of sulfuric acid, sulfur trioxide, an aqueous solution of phosphoric acid, pyrophosphoric acid, polyphosphoric acid, benzenesulfonic acid, p-toluenesulfonic acid and SO4 2- / M x O y One or more types of solid acid catalysts.

[0017] Patent CN104086593B uses hydrogen chloride / hydrogen bromide or a substance capable of producing hydrogen chloride / hydrogen bromide as an acidic catalyst, and hydrogen chloride / hydrogen bromide is a very volatile substance, and a large amount of addition is required to maintain the catalyst concentration. At the same time, volatile acids can also cause corrosion and damage to equipment. The acidic catalyst of the present invention is a non-volatile acid, which is non-volatile, has a high utilization rate, and a correspondingly small amount of use, which also reduces the impurity residues in the final product.

[0018] According to the method for preparing a phenethyl bridged DOPO derivative, the yield of the phenethyl bridged DOPO derivative is ≥ 90% and the purity is 90-96%.

[0019] The yield of patent CN104086593B is not high, generally less than 90%. At the same time, patent CN104086593B needs to use a solvent, resulting in the need for re-precipitation in the post-processing process, high process complexity, and low product purity. The present invention adopts a melting method for direct reaction, does not use an organic solvent, has few side reactions, few impurities, high reaction selectivity, and does not require a special post-processing procedure. Therefore, the product has not only a high yield, but also a high purity.

[0020] The present invention also provides an application of a phenethyl bridged DOPO derivative, which is used as a flame retardant in the preparation of flame-retardant polyester fibers. The phenethyl bridged DOPO derivative is prepared by the preparation method of a phenethyl bridged DOPO derivative as described in any one of the above items, and has the following structural formula:

[0021]

[0022] As the preferred technical solution:

[0023] The specific process of the application of a phenethyl bridged DOPO derivative as described above is as follows: after melt blending a phenethyl bridged DOPO derivative and polyester in a mass ratio of 1:2 to 10 to obtain a flame retardant masterbatch, 2 to 5 wt% of the flame retardant masterbatch is added to the polyester chips or melt direct spinning process for melt spinning and drawing and winding to obtain a flame retardant polyester fiber.

[0024] In the application of a phenethyl bridged DOPO derivative as described above, the temperature of melt blending is 260-280° C., the temperature of melt spinning is 270-300° C., the speed of drawing and winding is 300-3000 m / min, and the multiple of drawing and winding is 1.5-4.5.

[0025] In the application of the phenylethyl bridged DOPO derivative as described above, the polyester is polyethylene terephthalate, polypropylene terephthalate or polybutylene terephthalate.

[0026] By using the phenylethyl bridged DOPO derivative as described above, the flame retardant polyester fiber is colorless and transparent, has a breaking strength of 2.4-3.1 cN / dtex, a breaking elongation of 40-60%, and a limiting oxygen index (LOI) ≥28.5%.

[0027] Principle of the invention:

[0028] The reaction time for preparing the phenethyl bridged DOPO derivatives of the present invention is significantly lower than that of CN104086593B, because the reaction mechanisms of the two are different.

[0029] The reaction mechanism of CN104086593B is as follows: the first DOPO compound attacks the carbonyl group of the aromatic ketone to produce an α-hydroxyphosphonate, the α-hydroxyl group in the α-hydroxyphosphonate is then replaced by nucleophilic hydrogen chloride (or hydrogen bromide) to produce water and an α-chlorophosphonate (or α-bromophosphonate), the α-chlorophosphonate (or α-bromophosphonate) regenerates hydrogen chloride (or hydrogen bromide) and a C=C-containing substituted vinylphosphonate through an elimination reaction, the C=C in the C=C-containing substituted vinylphosphonate then undergoes an addition reaction with the second DOPO compound to obtain the final product, and this method is a typical halogenated hydrocarbon elimination mechanism;

[0030] At present, DOPO compounds are DOPO and aromatic ketones are For example, the first DOPO attack The carbonyl group produces Should The α-hydroxyl group in the molecule is then replaced by a nucleophilic HX (X is Cl or Br) to produce water and (This process takes a long time), Regeneration of HX by elimination reaction and Should The C=C in the reaction then reacts with the second DOPO to obtain the final product.

[0031] The reaction principle of the present invention is: the first DOPO reacts with the unsaturated double bond or triple bond in the bridging substrate to generate a C=C-containing intermediate or a hydroxyl-containing intermediate. The hydroxyl-containing intermediate is protonated under the action of an acidic catalyst and removes a molecule of water to become a C=C-containing intermediate. The second DOPO reacts with the C=C in the C=C-containing intermediate to obtain the final product. This method is a typical alcohol elimination mechanism. Since the present invention avoids the halogenation process of alcohol, the reaction time is greatly shortened.

[0032] When the bridging substrate is The specific reaction mechanism is: the first DOPO and The unsaturated double bonds in Under the action of acidic catalyst, it is protonated and loses a molecule of water to become The second DOPO and The C=C in the reaction undergoes an addition reaction to obtain the final product

[0033] When the bridging substrate is The specific reaction mechanism is: protonation under the action of acidic catalyst, Remove one water molecule to form It then adds to the first DOPO to form Under the action of acidic catalyst, it is protonated and a water molecule is removed to form The second DOPO and The C=C in the reaction undergoes an addition reaction to obtain the final product

[0034] When the bridging substrate is The specific reaction mechanism is: the first DOPO and The unsaturated triple bond in the reaction generates an intermediate containing C=C The second DOPO reacts with the C=C in the C=C containing intermediate to obtain the final product This process has a faster reaction rate because only two molecules are involved in the addition reaction.

[0035] When the bridging substrate is The specific reaction mechanism is: First Double bond addition occurs with the first DOPO to form Under the action of acidic catalyst, it is protonated and a water molecule is removed to form Then C=C adds a second DOPO to obtain the final product

[0036] When the bridging substrate is The specific reaction mechanism is: the first DOPO adds to the C=C double bond to form Under the action of acidic catalyst, it is protonated and a water molecule is removed to form The second DOPO and The C=C in the reaction undergoes an addition reaction to obtain the final product Beneficial effects:

[0037] The acid catalyst used in the present invention is a non-volatile acid catalyst. This type of acid does not volatilize during the reaction process, has little harm to the environment, and is less corrosive to equipment.

[0038] The invention does not use organic solvents, does not require post-treatment and re-precipitation processes, has a small amount of three wastes, has low process complexity, short reaction time, high efficiency, and is easy for large-scale production.

[0039] The preparation method of the present invention obtains the product by directly subjecting the alcohol to an elimination reaction. In contrast, the prior art requires first replacing the generated hydroxyl group with a halogenated hydrocarbon and then subjecting the halogenated hydrocarbon to an elimination reaction. This process is more complicated than the direct elimination of the alcohol; therefore, the preparation method of the present invention has a higher yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is the infrared spectrum of the phenethyl bridged DOPO derivative prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0041] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0042] Detection method of relevant indicators in the embodiment:

[0043] Yield of DOPO derivatives: Yield = actual product mass / theoretical product mass × 100%;

[0044] Purity of DOPO derivatives: Determined in accordance with the standard "GB / T, 6040-2019, General Rules for Infrared Spectroscopic Analysis Methods";

[0045] Fiber breaking strength and elongation at break: Tested in accordance with the standard "GB / T, 9997-1988, Determination of breaking strength and elongation at break of chemical fiber single fiber";

[0046] Limiting oxygen index of fiber: measured in accordance with the standard "FZ / T, 50016-2023, Chemical fiber, Combustion performance test method, Oxygen index method".

[0047] The structural formula of the phenethyl bridged DOPO derivatives prepared in Examples 1 to 15 is:

[0048]

[0049] Example 1

[0050] A method for preparing a phenethyl bridged DOPO derivative is as follows:

[0051] (1) Raw material preparation:

[0052] Bridging substrate: The structural formula is

[0053] Acidic catalyst: aqueous sulfuric acid solution, concentration 98wt%;

[0054] DOPO;

[0055] (2) The bridged substrate, DOPO and acid catalyst are mixed uniformly, heated to 140° C. and kept warm for 4 hours, poured out while hot, cooled naturally, crushed, and washed with water, C1-C6 fatty alcohol or a mixture thereof until neutral, thereby obtaining a phenethyl bridged DOPO derivative;

[0056] The molar ratio of DOPO to the bridging substrate is 2:1, and the molar ratio of DOPO to the acidic catalyst is 1:0.1.

[0057] The yield of the final phenethyl-bridged DOPO derivative was 91.5% and the purity was 94.5%.

[0058] Example 2

[0059] A method for preparing a phenethyl bridged DOPO derivative is as follows:

[0060] (1) Raw material preparation:

[0061] Bridging substrate: The structural formula is

[0062] Acidic catalyst: sulfur trioxide;

[0063] DOPO;

[0064] (2) The bridged substrate, DOPO and acid catalyst are mixed uniformly, heated to 150° C. and kept warm for 3 h, poured out while hot, cooled naturally, crushed, and washed with water, C1-C6 fatty alcohol or a mixture thereof until neutral, thereby obtaining a phenethyl bridged DOPO derivative;

[0065] The molar ratio of DOPO to the bridging substrate is 3:1, and the molar ratio of DOPO to the acidic catalyst is 1:1.

[0066] The yield of the phenethyl bridged DOPO derivative finally prepared was 91% and the purity was 93%. The infrared spectrum test of the phenethyl bridged DOPO derivative was performed, and the results were as follows: Figure 1 shown.

[0067] Example 3

[0068] A method for preparing a phenethyl bridged DOPO derivative is as follows:

[0069] (1) Raw material preparation:

[0070] Bridging substrate: The structural formula is

[0071] Acidic catalyst: phosphoric acid aqueous solution (concentration 85%);

[0072] DOPO;

[0073] (2) The bridged substrate, DOPO and acid catalyst are mixed uniformly, heated to 170° C. and kept warm for 2 h, poured out while hot, cooled naturally, crushed, and washed with water, C1-C6 fatty alcohol or a mixture thereof until neutral, thereby obtaining a phenethyl bridged DOPO derivative;

[0074] The molar ratio of DOPO to the bridging substrate is 3.5:1, and the molar ratio of DOPO to the acidic catalyst is 1:2.

[0075] The yield of the final phenethyl-bridged DOPO derivative was 92% and the purity was 90%.

[0076] Example 4

[0077] A method for preparing a phenethyl bridged DOPO derivative is as follows:

[0078] (1) Raw material preparation:

[0079] Bridging substrate: The structural formula is

[0080] Acidic catalyst: sulfur trioxide;

[0081] DOPO;

[0082] (2) The bridged substrate, DOPO and acid catalyst are mixed uniformly, heated to 140° C. and kept warm for 8 hours, poured out while hot, cooled naturally, crushed, and washed with water, C1-C6 fatty alcohol or a mixture thereof until neutral, thereby obtaining a phenethyl bridged DOPO derivative;

[0083] The molar ratio of DOPO to the bridging substrate is 2.6:1, and the molar ratio of DOPO to the acidic catalyst is 1:0.8.

[0084] The yield of the final phenethyl-bridged DOPO derivative was 92% and the purity was 96%.

[0085] Example 5

[0086] A method for preparing a phenethyl bridged DOPO derivative is as follows:

[0087] (1) Raw material preparation:

[0088] Bridging substrate: The structural formula is

[0089] Acidic catalyst: pyrophosphoric acid;

[0090] DOPO;

[0091] (2) The bridged substrate, DOPO and acid catalyst are mixed uniformly, heated to 150° C. and kept warm for 6 hours, poured out while hot, cooled naturally, crushed, and washed with water, C1-C6 fatty alcohol or a mixture thereof until neutral, thereby obtaining a phenethyl bridged DOPO derivative;

[0092] The molar ratio of DOPO to the bridging substrate is 2.5:1, and the molar ratio of DOPO to the acidic catalyst is 1:1.4.

[0093] The yield of the final phenethyl-bridged DOPO derivative was 90.5% and the purity was 91.5%.

[0094] Example 6

[0095] A method for preparing a phenethyl bridged DOPO derivative is as follows:

[0096] (1) Raw material preparation:

[0097] Bridging substrate: The structural formula is

[0098] Acidic catalyst: phosphoric acid aqueous solution (concentration 85%);

[0099] DOPO;

[0100] (2) The bridged substrate, DOPO and acid catalyst are mixed uniformly, heated to 170° C. and kept warm for 4 hours, poured out while hot, cooled naturally, crushed, and washed with water, C1-C6 fatty alcohol or a mixture thereof until neutral, thereby obtaining a phenethyl bridged DOPO derivative;

[0101] The molar ratio of DOPO to the bridging substrate is 2.1:1, and the molar ratio of DOPO to the acidic catalyst is 1:1.

[0102] The yield of the final phenethyl-bridged DOPO derivative was 90% and the purity was 93%.

[0103] Example 7

[0104] A method for preparing a phenethyl bridged DOPO derivative is as follows:

[0105] (1) Raw material preparation:

[0106] Bridging substrate: The structural formula is

[0107] Acidic catalyst: phosphoric acid aqueous solution (concentration 85%);

[0108] DOPO;

[0109] (2) The bridged substrate, DOPO and acid catalyst are mixed uniformly, heated to 50° C. and then kept warm for 2 h, poured out while hot, cooled naturally, crushed, and washed with water, C1-C6 fatty alcohol or a mixture thereof until neutral, thereby obtaining a phenethyl bridged DOPO derivative;

[0110] The molar ratio of DOPO to the bridging substrate is 3.1:1, and the molar ratio of DOPO to the acidic catalyst is 1:1.7.

[0111] The yield of the final phenethyl-bridged DOPO derivative was 92.5% and the purity was 91%.

[0112] Example 8

[0113] A method for preparing a phenethyl bridged DOPO derivative is as follows:

[0114] (1) Raw material preparation:

[0115] Bridging substrate: The structural formula is

[0116] Acidic catalyst: pyrophosphoric acid;

[0117] DOPO;

[0118] (2) The bridged substrate, DOPO and acid catalyst are mixed uniformly, heated to 60° C. and kept warm for 1 hour, poured out while hot, cooled naturally, crushed, and washed with water, C1-C6 fatty alcohol or a mixture thereof until neutral, thereby obtaining a phenethyl bridged DOPO derivative;

[0119] The molar ratio of DOPO to the bridging substrate is 3.1:1, and the molar ratio of DOPO to the acidic catalyst is 1:1.4.

[0120] The yield of the final phenethyl-bridged DOPO derivative was 92% and the purity was 90%.

[0121] Example 9

[0122] A method for preparing a phenethyl bridged DOPO derivative is as follows:

[0123] (1) Raw material preparation:

[0124] Bridging substrate: The structural formula is

[0125] Acidic catalyst: polyphosphoric acid, degree of polymerization 4;

[0126] DOPO;

[0127] (2) The bridged substrate, DOPO and acid catalyst are mixed uniformly, heated to 80° C. and kept warm for 0.5 h, poured out while hot, cooled naturally, crushed, and washed with water, C1-C6 fatty alcohol or a mixture thereof until neutral, thereby obtaining a phenethyl bridged DOPO derivative;

[0128] The molar ratio of DOPO to the bridging substrate is 3.3:1, and the molar ratio of DOPO to the acidic catalyst is 1:0.4.

[0129] The yield of the final phenethyl-bridged DOPO derivative was 93% and the purity was 94%.

[0130] Example 10

[0131] A method for preparing a phenethyl bridged DOPO derivative is as follows:

[0132] (1) Raw material preparation:

[0133] Bridging substrate: The structural formula is

[0134] Acidic catalyst: pyrophosphoric acid;

[0135] DOPO;

[0136] (2) The bridged substrate, DOPO and acid catalyst are mixed uniformly, heated to 140° C. and kept warm for 4 hours, poured out while hot, cooled naturally, crushed, and washed with water, C1-C6 fatty alcohol or a mixture thereof until neutral, thereby obtaining a phenethyl bridged DOPO derivative;

[0137] The molar ratio of DOPO to the bridging substrate is 3.2:1, and the molar ratio of DOPO to the acidic catalyst is 1:0.5.

[0138] The yield of the final phenethyl-bridged DOPO derivative was 91.5% and the purity was 94%.

[0139] Embodiment 11

[0140] A method for preparing a phenethyl bridged DOPO derivative is as follows:

[0141] (1) Raw material preparation:

[0142] Bridging substrate: The structural formula is

[0143] Acidic catalyst: benzenesulfonic acid;

[0144] DOPO;

[0145] (2) The bridged substrate, DOPO and acid catalyst are mixed uniformly, heated to 160° C. and kept warm for 3 h, poured out while hot, cooled naturally, crushed, and washed with water, C1-C6 fatty alcohol or a mixture thereof until neutral, thereby obtaining a phenethyl bridged DOPO derivative;

[0146] The molar ratio of DOPO to the bridging substrate is 3.0:1, and the molar ratio of DOPO to the acidic catalyst is 1:1.2.

[0147] The yield of the final phenethyl-bridged DOPO derivative was 94% and the purity was 91%.

[0148] Example 12

[0149] A method for preparing a phenethyl bridged DOPO derivative is as follows:

[0150] (1) Raw material preparation:

[0151] Bridging substrate: The structural formula is

[0152] Acidic catalyst: polyphosphoric acid, degree of polymerization 4;

[0153] DOPO;

[0154] (2) The bridged substrate, DOPO and acid catalyst are mixed uniformly, heated to 170° C. and kept warm for 2 h, poured out while hot, cooled naturally, crushed, and washed with water, C1-C6 fatty alcohol or a mixture thereof until neutral, thereby obtaining a phenethyl bridged DOPO derivative;

[0155] The molar ratio of DOPO to the bridging substrate is 2.7:1, and the molar ratio of DOPO to the acidic catalyst is 1:0.3.

[0156] The yield of the final phenethyl-bridged DOPO derivative was 92.5% and the purity was 95%.

[0157] Embodiment 13

[0158] A method for preparing a phenethyl bridged DOPO derivative is as follows:

[0159] (1) Raw material preparation:

[0160] Bridging substrate: The structural formula is

[0161] Acidic catalyst: benzenesulfonic acid;

[0162] DOPO;

[0163] (2) The bridged substrate, DOPO and acid catalyst are mixed uniformly, heated to 140° C. and kept warm for 4 hours, poured out while hot, cooled naturally, crushed, and washed with water, C1-C6 fatty alcohol or a mixture thereof until neutral, thereby obtaining a phenethyl bridged DOPO derivative;

[0164] The molar ratio of DOPO to the bridging substrate is 3.0:1, and the molar ratio of DOPO to the acidic catalyst is 1:1.3.

[0165] The yield of the final phenethyl-bridged DOPO derivative was 92% and the purity was 90%.

[0166] Embodiment 14

[0167] A method for preparing a phenethyl bridged DOPO derivative is as follows:

[0168] (1) Raw material preparation:

[0169] Bridging substrate: The structural formula is

[0170] Acidic catalyst: p-toluenesulfonic acid;

[0171] DOPO;

[0172] (2) The bridged substrate, DOPO and acid catalyst are mixed uniformly, heated to 150° C. and kept warm for 3 h, poured out while hot, cooled naturally, crushed, and washed with water, C1-C6 fatty alcohol or a mixture thereof until neutral, thereby obtaining a phenethyl bridged DOPO derivative;

[0173] The molar ratio of DOPO to the bridging substrate is 3.1:1, and the molar ratio of DOPO to the acidic catalyst is 1:2.

[0174] The yield of the final phenethyl-bridged DOPO derivative was 95% and the purity was 92%.

[0175] Embodiment 15

[0176] A method for preparing a phenethyl bridged DOPO derivative is as follows:

[0177] (1) Raw material preparation:

[0178] Bridging substrate: The structural formula is

[0179] Acidic catalyst: SO4 2- / TiO2 solid acid;

[0180] DOPO;

[0181] (2) The bridged substrate, DOPO and acid catalyst are mixed uniformly, heated to 170° C. and kept warm for 1 hour, poured out while hot, cooled naturally, crushed, and washed with water, C1-C6 fatty alcohol or a mixture thereof until neutral, thereby obtaining a phenethyl bridged DOPO derivative;

[0182] The molar ratio of DOPO to the bridging substrate is 2.3:1, and the molar ratio of DOPO to the acidic catalyst is 1:0.2.

[0183] The yield of the final phenethyl-bridged DOPO derivative was 94.5% and the purity was 93%.

[0184] Example 16

[0185] A method for preparing a flame retardant polyester fiber is as follows:

[0186] (1) Raw material preparation:

[0187] Flame retardant: the phenethyl bridged DOPO derivative prepared in Example 1;

[0188] Polyester: polyethylene terephthalate;

[0189] (2) After melt-blending a flame retardant and polyester in a mass ratio of 1:2 to obtain a flame retardant masterbatch, 2 wt % of the flame retardant masterbatch was added to the polyester chip process for melt spinning and draft winding to obtain a flame retardant polyester fiber;

[0190] The temperature of melt blending is 260° C., the temperature of melt spinning is 270° C., the speed of drawing and winding is 300 m / min, and the multiple of drawing and winding is 1.5.

[0191] The flame-retardant polyester fiber finally obtained is colorless and transparent, has a breaking strength of 2.4 cN / dtex, a breaking elongation of 45%, and a limiting oxygen index of 29%.

[0192] Embodiment 17

[0193] A method for preparing a flame retardant polyester fiber is as follows:

[0194] (1) Raw material preparation:

[0195] Flame retardant: phenethyl bridged DOPO derivative prepared in Example 4;

[0196] Polyester: polytrimethylene terephthalate;

[0197] (2) After melt blending a flame retardant and polyester in a mass ratio of 1:4 to obtain a flame retardant masterbatch, 4 wt% of the flame retardant masterbatch was added to the melt direct spinning process for melt spinning and draft winding to obtain a flame retardant polyester fiber;

[0198] The temperature of melt blending is 270° C., the temperature of melt spinning is 300° C., the speed of drawing and winding is 500 m / min, and the multiple of drawing and winding is 4.

[0199] The flame-retardant polyester fiber finally obtained is colorless and transparent, has a breaking strength of 2.6 cN / dtex, a breaking elongation of 50%, and a limiting oxygen index of 29%.

[0200] Embodiment 18

[0201] A method for preparing a flame retardant polyester fiber is as follows:

[0202] (1) Raw material preparation:

[0203] Flame retardant: phenethyl bridged DOPO derivative prepared in Example 7;

[0204] Polyester: polybutylene terephthalate;

[0205] (2) After melt-blending a flame retardant and polyester in a mass ratio of 1:5 to obtain a flame retardant masterbatch, 4 wt % of the flame retardant masterbatch was added to the polyester chip process for melt spinning and draft winding to obtain a flame retardant polyester fiber;

[0206] The temperature of melt blending is 260° C., the temperature of melt spinning is 280° C., the speed of drawing and winding is 3000 m / min, and the multiple of drawing and winding is 4.5.

[0207] The flame-retardant polyester fiber finally obtained is colorless and transparent, has a breaking strength of 3 cN / dtex, a breaking elongation of 52%, and a limiting oxygen index of 28.5%.

[0208] Embodiment 19

[0209] A method for preparing a flame retardant polyester fiber is as follows:

[0210] (1) Raw material preparation:

[0211] Flame retardant: phenethyl bridged DOPO derivative prepared in Example 10;

[0212] Polyester: polyethylene terephthalate;

[0213] (2) After melt-blending a flame retardant and polyester in a mass ratio of 1:8 to obtain a flame retardant masterbatch, 5 wt% of the flame retardant masterbatch was added to the melt direct spinning process for melt spinning and draft winding to obtain a flame retardant polyester fiber;

[0214] The temperature of melt blending is 280° C., the temperature of melt spinning is 280° C., the speed of drawing and winding is 2500 m / min, and the multiple of drawing and winding is 3.

[0215] The flame-retardant polyester fiber finally obtained is colorless and transparent, has a breaking strength of 3.1 cN / dtex, a breaking elongation of 60%, and a limiting oxygen index of 30.5%.

[0216] Embodiment 20

[0217] A method for preparing a flame retardant polyester fiber is as follows:

[0218] (1) Raw material preparation:

[0219] Flame retardant: phenethyl bridged DOPO derivative prepared in Example 13;

[0220] Polyester: polytrimethylene terephthalate;

[0221] (2) After melt-blending a flame retardant and polyester in a mass ratio of 1:10 to obtain a flame retardant masterbatch, 5 wt% of the flame retardant masterbatch was added to the polyester chip process for melt spinning and draft winding to obtain a flame retardant polyester fiber;

[0222] The temperature of melt blending is 280° C., the temperature of melt spinning is 280° C., the speed of drawing and winding is 2000 m / min, and the multiple of drawing and winding is 2.5.

[0223] The flame-retardant polyester fiber finally obtained is colorless and transparent, has a breaking strength of 2.8 cN / dtex, a breaking elongation of 40%, and a limiting oxygen index of 28.5%.

Claims

1. A method for preparing a phenethyl bridged DOPO derivative, characterized in that: The bridging substrate, DOPO and the acid catalyst are mixed uniformly, heated to a temperature T and then kept warm for a reaction time t, and a phenethyl bridged DOPO derivative is obtained by post-treatment, wherein the molar ratio of DOPO to the bridging substrate is 2 to 3.5:1; The bridging substrate is The temperature T is 140-170°C, and the duration t is 2-4h; Alternatively, the bridging substrate is The temperature T is 140-170°C, and the duration t is 4-8h; Alternatively, the bridging substrate is The temperature T is 50-80°C, and the duration t is 0.5-2h; Alternatively, the bridging substrate is The temperature T is 140-170°C, and the duration t is 2-4h; Alternatively, the bridging substrate is The temperature T is 140-170°C, and the time t is 1-4h.

2. The method for preparing a phenethyl bridged DOPO derivative according to claim 1, characterized in that: The molar ratio of DOPO to the acid catalyst is 1:0.1-2.

3. The method for preparing a phenethyl bridged DOPO derivative according to claim 2, characterized in that: Acidic catalysts include aqueous sulfuric acid, sulfur trioxide, aqueous phosphoric acid, pyrophosphoric acid, polyphosphoric acid, benzenesulfonic acid, p-toluenesulfonic acid and SO4 2- / M x O y One or more types of solid acid catalysts.

4. The method for preparing a phenethyl bridged DOPO derivative according to claim 1, characterized in that: The yield of the phenethyl bridged DOPO derivative is ≥90%, and the purity is 90-96%.

5. An application of a phenethyl bridged DOPO derivative, characterized in that: The phenethyl bridged DOPO derivative is used as a flame retardant in the preparation of flame-retardant polyester fibers. The phenethyl bridged DOPO derivative is prepared by the preparation method of the phenethyl bridged DOPO derivative as described in any one of claims 1 to 4, and the structural formula is as follows:

6. The use of a phenethyl bridged DOPO derivative according to claim 5, characterized in that: The specific process is: after melt blending the styrene-bridged DOPO derivative and polyester in a mass ratio of 1:2 to 10 to obtain a flame-retardant masterbatch, 2 to 5 wt% of the flame-retardant masterbatch is added to the polyester chips or melt direct spinning process for melt spinning and drawing and winding to obtain the flame-retardant polyester fiber.

7. The use of a phenethyl bridged DOPO derivative according to claim 6, characterized in that: The temperature of melt blending is 260-280° C., the temperature of melt spinning is 270-300° C., the speed of drawing and winding is 300-3000 m / min, and the multiple of drawing and winding is 1.5-4.

5.

8. The use of a phenethyl bridged DOPO derivative according to claim 6, characterized in that: The polyester is polyethylene terephthalate, polytrimethylene terephthalate or polybutylene terephthalate.

9. The use of a phenethyl bridged DOPO derivative according to claim 6, characterized in that: The flame retardant polyester fiber is colorless and transparent, has a breaking strength of 2.4 to 3.1 cN / dtex, an elongation at break of 40 to 60%, and a limiting oxygen index of ≥28.5%.

Images