KR20130075839A - Method for preparing phosphinate flame retardant - Google Patents

Abstract

PURPOSE: A manufacturing method of a phosphinate system flame retardant is provided to present a phosphinate system flame retardant with high yield, excellent purity and colorability. CONSTITUTION: A manufacturing method of a phosphinate system flame retardant indicated as the following chemical formula 2.comprises a step of esterificating (meth) acrylic anhydride and phosphinate-based alcohol indicated as the following chemical formula 1.for 2-12 hours until reaching the conversion ratio of 85-100 %. In the chemical formula 1, the R1 is a C1-4 saturated or non-saturated hydrocarbon group, the R1 is a C1-4 saturated or non-saturated hydrocarbon group and the R2 is H or a methyl group. The mole ratio of phosphinate system alcohol : (meta) acrylic anhydride is 1:0.5-1:1.5.

Description

Method for preparing phosphinate flame retardant {Method for Preparing Phosphinate Flame Retardant}

The present invention relates to a method for producing a phosphinate-based flame retardant. More specifically, the present invention relates to a method for producing a high purity phosphinate flame retardant by reacting a (meth) acrylic anhydride and a phosphinate alcohol compound.

Methacrylic resins have excellent scratch resistance due to excellent transparency, weather resistance, and excellent rigidity. Due to these characteristics, it is used not only for general molded products, but also for various materials such as materials of electric and electronic products, display materials, optical materials, building materials, automobile products, etc., and the amount thereof is increasing, but its use is limited due to flammability. It is becoming.

In general, a method of blending an antimony-based, halogen-based, phosphorus-based or nitrogen-containing compound to impart flame retardancy to overcome flammability disadvantages of resins is known and used. Since halogen-based flame retardants impart high flame retardancy in a relatively small amount, it is most widely used. However, when halogen-based flame retardants are used, corrosive gases are generated during processing to cause corrosion of processing equipment, and during combustion, dioxin or hydrogen halide gas is used. Etc. There are disadvantages of generating toxic gases. Therefore, there is a tendency to gradually increase the restrictions of its use all over the world, which has led to a sharp increase in demand for resins that do not contain halogen-based flame retardants. Flame retardants replace halogen-based flame retardants. Currently, the most researched and commonly used phosphorus-based flame retardants. Phosphorus-based flame retardants are superior in the corrosiveness and toxicity of halogen-based flame retardants, but their flame retardant performance is lower than that of halogen-based flame retardants. As a result, the inherent physical properties of the resin are deteriorated. Above all, since the polymer resin capable of acting as a flame retardant is limited to a resin containing polycarbonate and polyphenylene ether, the inherent advantages of methacryl-based resins are a decrease in transparency and scratch resistance.

The present invention proposes the production of a high refractive index acrylic phosphorus monomer having a high refractive index and high flame retardancy and heat resistance which can simultaneously achieve physical properties including flame retardance, high refractive index and heat resistance performance while overcoming the above problems.

Japanese Laid-Open Patent Publication No. 2009-109425 discloses an example of copolymerization using an acrylic monomer containing a phosphinate group, but in a method of synthesizing the monomer, an excess of methacrylic acid is directly added at a high temperature using a strong acid catalyst such as sulfuric acid. There is a method of carrying out the esterification reaction. However, the direct esterification reaction is not suitable for industrial production due to the low conversion rate, and even if the reaction temperature is increased to increase the reaction conversion rate, it is difficult to obtain a product with high yield due to the polymerization reaction of (meth) acrylic acid as a raw material. Rather, it causes serious problems in the machinery used for the reaction, causing problems such as deterioration of the color of the product.

MEANS TO SOLVE THE PROBLEM This inventor came to develop the method of synthesizing the phosphorus type monomer which has a specific structure, and contains a (meth) acryl group by a new method, in order to solve the existing problem.

It is an object of the present invention to provide a method for producing a high purity phosphinate flame retardant.

Another object of the present invention is to provide a method for producing a high purity phosphinate flame retardant in high yield.

Still another object of the present invention is to provide a method for preparing a colorless phosphinate flame retardant.

According to an embodiment of the present invention, the (meth) acrylic acid anhydride and the phosphinate-based alcohol represented by the following formula (1) is ester-reacted for 2 to 12 hours at 0 ~ 100 ℃ until the conversion rate is 90 to 100% It provides a method for producing a phosphinate-based flame retardant represented by the following formula (2).

(In Formula 1, R1 is a C1-C4 saturated or unsaturated hydrocarbon group.)

(In Formula 2, R1 is a C1-C4 saturated or unsaturated hydrocarbon group, R2 is H or methyl group.)

The molar ratio of the phosphinate alcohol: the (meth) acrylic anhydride is 1: 1.0 to 1: 1.5.

In addition, the reaction is carried out in the presence of an organic solvent selected from the group consisting of benzene, toluene, xylene, n-hexane, cyclohexane, n-heptane, n-octane, ethyl ether, acetonitrile, methylene chloride or mixtures thereof. It is done.

According to an embodiment of the present invention, the reaction may be reacted in the presence of at least one catalyst selected from the group consisting of alkali metal salts, amine compounds or organic acids, wherein the catalyst is 0.01 to a weight of (meth) acrylic anhydride. Can be added at 5.0 wt%.

In addition, the reaction may be performed by adding at least one polymerization inhibitor selected from the group consisting of butylated hydroxytoluene (BHT), hydroquinone, p-benzoquinone and the like.

According to another embodiment of the present invention, the (meth) acrylic acid produced after the reaction is terminated may further comprise the step of distillation and recovery at 5 ~ 100 mmHg pressure and 30 ~ 100 ℃ temperature.

According to another embodiment of the present invention, after completion of the (meth) acrylic acid recovery step, the reaction product may further comprise a step of purification through an alkali washing, concentration and filtration process.

The phosphinate-based flame retardant prepared by the above production method preferably has a purity of 90% or more and a yield of 85% or more.

In addition, the phosphinate-based flame retardant prepared by the above production method preferably has an APHA Color value of A-10 to A-50 based on ASTM D1209.

The phosphinate flame retardant manufacturing method of the present invention is excellent in synthetic yield, the phosphinate flame retardant prepared by the production method is excellent in purity and colorability.

1 is a diagram showing a 1H-NMR peak of the phosphinate alcohol used in the present invention.
Figure 2 is a view showing the 1H-NMR peak of the phosphinate-based flame retardant of the present invention.

Hereinafter, the present invention will be described in detail.

Phosphate Flame retardant  Manufacturing method

The phosphinate flame retardant of the present invention is prepared by reacting (meth) acrylic anhydride and phosphinate alcohol as a reactant.

The phosphinate alcohol used in the present invention is characterized by represented by the following formula (1), the phosphinate-based flame retardant is a product of the present invention is represented by the formula (2).

[Formula 1]

(In Formula 1, R1 is a C1-C4 saturated or unsaturated hydrocarbon group.)

      [Formula 2]

(In Formula 2, R1 is a C1-C4 saturated or unsaturated hydrocarbon group, R2 is H or methyl group.)

The phosphinate-based alcohol may be prepared by reacting 9,10-dihydro-9-oxy-10-hospapenantorene-10-oxide and paraformaldehyde. Paraformaldehyde used in the present invention can be used in a molar ratio of 0.9 to 2.0 with respect to 9,10-dihydro-9-oxy-10-hospphenanthrene-10-oxide, more preferably 0.9 to 1.1 Can be used as a ratio. The reaction proceeds without a catalyst, the reaction temperature may be 50 ~ 110 ℃, more preferably at 70 ~ 90 ℃. The formation of the phosphinate alcohol can be confirmed through the 1H-NMR peak of FIG.

In the present invention, the (meth) acrylic acid anhydride may be prepared by a method of reacting (meth) acrylic acid halide with (meth) acrylic acid (method 1), and a method of reacting (meth) acrylic acid with acetic anhydride (method 2). .

Since method 1 has a problem in that handling of (meth) acrylic acid halide is not easy and reaction stability is inferior, it is preferable that (meth) acrylic anhydride is produced by method 2.

In particular, in the case of method 2, since it can be carried out in the presence of the catalyst used in the present invention, it has the effect that there is no need to further use or purify the catalyst. The catalyst may be used in an amount of 0.01 to 3.0%, preferably 0.1 to 1.0% based on the weight of the (meth) acrylic acid.

In addition, in the method 2, the molar ratio of (meth) acrylic acid: acetic anhydride may be 1: 0.2 to 1: 0.5, for example, 1: 0.45 to 1: 0.5.

Moreover, in the said method 2, 1 or more types of polymerization inhibitors chosen from the group which consists of butylated hydroxy toluene (BHT), p-benzoquinone, etc. can further be included.

The molar ratio of the phosphinate alcohol used in the present invention: the (meth) acrylic acid anhydride can be reacted at 1: 0.5 to 1: 1.5, more preferably 1: 0.9 to 1: 1.1.

The solvent used in the present invention may be an organic solvent selected from the group consisting of toluene, xylene, n-hexane, cyclohexane, n-heptane, n-octane, ethyl ether, acetonitrile, methylene chloride or mixtures thereof.

The reaction temperature of the present invention may be 0 to 100 ° C, and more preferably 40 to 90 ° C. If the reaction temperature is lower than 0 ℃, the reaction rate is excessively lowered and is not effective. If the reaction temperature exceeds 100 ℃, even if a polymerization inhibitor is used, polymerization of (meth) acrylic anhydride or phosphinate flame retardant may occur. to be. Therefore, the present invention can produce a high-purity phosphinate-based flame retardant by not increasing the reaction temperature to a temperature at which side reactions can occur.

In addition, the reaction time of the present invention can be made for 2 to 12 hours until the reaction conversion rate is 85 to 100%, more preferably performed for 5 to 10 hours.

In the present invention, the reaction can be carried out even under the non-catalyst condition during the reaction, but it is more preferable to use a catalyst used in a conventional esterification reaction. Examples of the catalyst include alkali metal salts such as lithium acetate, sodium acetate, and potassium propionate, amine compounds such as pyridine, triethylamine, and triethyldiamine, sulfuric acid, boric acid, and methane. Organic acids, such as sulfonic acid and p-toluenesulfonic acid, etc. are mentioned. The catalyst is preferably used in an amount of 0.001 to 3.0% by weight based on (meth) crylic anhydride. More preferably 0.1 to 1.0% by weight can be used.

The catalyst is added to (meth) acrylic anhydride with phosphinate alcohol, or to phosphinate alcohol with (meth) acrylic anhydride, or (meth) acrylic anhydride, phosphinate alcohol, and The catalysts may be added in any order, but are not limited to these.

In the present invention, at least one polymerization inhibitor selected from the group consisting of butylated hydroxytoluene (BHT), hydroquinone, p-benzoquinone and the like may be added to prevent polymerization that may occur during the reaction. . The polymerization inhibitor may be included in an amount of 0.01 to 0.5% based on the weight of the phosphinate-based flame retardant.

After the reaction is completed (meth) acrylic acid is produced from (meth) acrylic acid anhydride, the (meth) acrylic acid can be recovered through distillation. Pressure conditions for distillation are 5 to 100 mmHg, more preferably 5 to 20 mmHg. Temperature conditions are 30-100 degreeC, More preferably, it is 50-80 degreeC. The (meth) acrylic acid recovered at this time can be used to prepare (meth) acrylic anhydride.

After the (meth) acrylic acid is removed, the phosphinate-based flame retardant of the present invention can be purified using a process of alkali washing with water, concentration and filtration.

The phosphinate-based flame retardant prepared by the above process can be confirmed by analyzing the 1H-NMR peak of FIG.

In addition, the phosphinate-based flame retardant prepared through the above process is preferably color close to colorless. In the present invention, the chromaticity may be APHA Color (Hazen Color) measured by the Pt-Co measurement method according to ASTM D 1209. In the measurement method, the chromaticity ranges from 0 to 500, the chromaticity of Platinum-Cobalt Stock Solution becomes APHA 500, and the chromaticity of ultrapure water (DI water) used as a diluent corresponds to APHA 0. At this time, depending on the degree of dilution it is classified quantitatively in steps of 1 to 500. APHA Color value of the present invention is preferably A-10 ~ A-50.

Hereinafter, preferred embodiments of the present invention will be described. However, the following examples are only a preferred embodiment of the present invention, and the present invention is not limited by the following examples.

Example

Manufacturing example ( Phosphate  Alcohol)

Into a reactor equipped with a stirrer, a thermometer, and a condenser, 216.2 g (1.0 mol) of 9,10-dihydro-9-oxy-10-hosphenanthrene-10-oxide and 216.2 g of toluene were added thereto, and the temperature was raised to 70-90 ° C. Stir. Slowly add 30.03 g of paraformaldehyde. After the reaction, the reaction was performed at 70-90 ° C. for about 4 hours, and then confirmed by gas chromatography. After the reaction is completed, the mixture is cooled to room temperature and filtered. After filtration, a melting point of 246.2 g of a white crystal having a temperature of 170 to 171 ° C was obtained. The product was 100% yield, 99% purity.

Example  One

246.2 g (1.0 mol) of white crystals obtained in the preparation example, 154.17 g (1.0 mol) of methacrylic anhydride, 0.8 g of sodium acetate, 0.02 g of butylated hydroxytoluene were added and reacted at 90 ° C for 3 hours. After the reaction, it is confirmed by analyzing by gas chromatography. The obtained reaction solution was neutralized with an aqueous 10% sodium carbonate solution, washed once with 20% saline solution, and toluene was distilled off under reduced pressure to obtain a product containing a high viscosity clear liquid phosphinate group.

Example  2

The reaction was carried out in the same manner as in Example 1, except that the reaction temperature was reacted at 40 ° C. for 12 hours.

Comparative example  One

246.2 g (1.0 mol) of white crystals obtained in the preparation example, 172 g (2.0 mol) of methacrylic acid, 500 g of toluene, 1.7 g of hydroquinone, and 17 g of p-toluene sulfonic acid were added thereto, followed by dehydration at 100 to 120 ° C. for 16 hours. After the reaction, it is confirmed by analyzing by gas chromatography. The reaction solution obtained here was washed twice with 10% aqueous sodium carbonate solution and once with 20% brine, and then toluene was distilled off under reduced pressure to obtain a pale yellow high viscosity compound.

Comparative example  2

The reaction was carried out in the same manner as in Comparative Example 1 except that the reaction temperature was reacted at 120 ° C. or higher using xylene.

How to measure property

(1) Yield: measured using a formula of (the actual mole number / theoretical mole number of the product) * 100.

(2) Purity: Purity was measured through GC analysis.

(3) APHA Color value: measured by Pt-Co measurement method according to ASTM D 1209.

As shown in Table 1, the production method of the present invention can be seen that the colorless phosphinate-based flame retardant with high purity and high yield can be seen in the results of Examples 1 to 2.

On the other hand, it can be seen that the production method through the conventional acid catalyst esterification reaction yields and purity is lower and the color is also not excellent, such as pale yellow. In addition, in the case of Comparative Example 2 reacted in excess of 100 ℃ it was confirmed that the yield decrease due to some polymerization phenomenon.

Claims (11)

(Meth) acrylic anhydride and the phosphinate alcohol represented by the following formula (1) is represented by the following formula 2, characterized in that the ester reaction for 2 to 12 hours until the conversion rate is 85 to 100% at 0 ~ 100 ℃ Method for producing a phosphinate-based flame retardant.
[Formula 1]

(In Formula 1, R1 is a C1-C4 saturated or unsaturated hydrocarbon group.)
(2)

(In Formula 2, R1 is a C1-C4 saturated or unsaturated hydrocarbon group, R2 is H or methyl group.)
The method of claim 1, wherein the molar ratio of the phosphinate alcohol: the (meth) acrylic anhydride is 1: 0.5 to 1: 1.5.
The organic solvent of claim 1, wherein the reaction is selected from the group consisting of benzene, toluene, xylene, n-hexane, cyclohexane, n-heptane, n-octane, ethyl ether, acetonitrile, methylene chloride or mixtures thereof. A process for producing a phosphinate-based flame retardant, characterized by the following.
The method of claim 1, wherein the reaction is performed in the presence of at least one catalyst selected from the group consisting of alkali metal salts, amine compounds or organic acids.
The method for producing a phosphinate flame retardant according to claim 4, wherein the catalyst is added at 0.01 to 3.0 wt% based on the weight of the (meth) acrylic anhydride.
The phosphinate flame retardant according to claim 1, wherein the reaction is performed by adding at least one polymerization inhibitor selected from the group consisting of butylated hydroxytoluene (BHT), hydroquinone and p-benzoquinone. Method of preparation.
The phosphinate flame retardant of claim 1, further comprising distilling and recovering the (meth) acrylic acid produced after the reaction is completed at a pressure of 5 to 100 mmHg and a temperature of 30 to 100 ° C. Manufacturing method.
The method of claim 7, wherein after completion of the (meth) acrylic acid recovery step, the reaction product further comprises purifying through an alkali washing, concentration, and filtration process.
The method of claim 1, wherein the prepared phosphinate flame retardant is at least 90% pure, yield is at least 85%.
The method of claim 1, wherein the phosphinate flame retardant prepared according to ASTM D 1209 has an APHA Color value of A-10 to A-50.
A phosphinate flame retardant prepared by the method according to claim 1.

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