JP3012174B2 - Method for producing condensed phosphate ester - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process for producing a condensed phosphoric ester which has excellent thermal stability and which is added to a synthetic resin to give excellent flame retardancy and moldability.

[0002]

2. Description of the Related Art Synthetic resins are generally light, excellent in water resistance, chemical resistance, electrical insulation, mechanical properties, etc., and are easy to mold. It is widely used as an automotive material, a fiber material, and the like. On the other hand, synthetic resins are generally flammable,
Various proposals have been made for imparting flame retardancy. The most common means of flame retardation is a method of blending a flame retardant such as an organic halogen compound, a phosphorus compound, or an inorganic hydrate at the time of preparing a resin molded product.

[0003] Among the above flame retardants, organic halogen compounds are most widely used because they exhibit an excellent flame retardant effect on many synthetic resins. However, halogen-containing compounds are thermally decomposed during resin molding to generate hydrogen halide, polluting the working environment, corroding molds,
There is a problem of causing coloring or gelling of the resin. further,
There is also a problem that a large amount of smoke is generated together with hydrogen halide gas which is corrosive and harmful to the human body when burned by a fire or the like.

As a halogen-free flame retardant, inorganic hydrates such as aluminum hydroxide and magnesium hydroxide are known. However, these have small flame retardant effects,
In order to obtain sufficient flame retardancy, it is necessary to add a large amount, and there is a disadvantage that the physical properties of the resin are impaired. Phosphorus compounds, especially organic phosphoric esters, do not contain halogen and are widely used as flame retardants that provide good flame retardant effects. Representative organic phosphates include triaryl phosphates such as triphenyl phosphate (TPP), tricresyl phosphate (TCP), and trixylyl phosphate (TXP). However, these compounds have a relatively low boiling point, and have problems such as extruding the resin and volatilizing during molding to cause contamination of the mold and exuding to the surface of the molded article to impair the appearance. In addition, there is also a problem that it acts as a plasticizer and greatly reduces the heat resistance of the resin composition.

[0005] Phosphoric esters having low volatility include condensed phosphoric esters described in JP-B-51-39271, JP-B-54-32818, JP-B-62-25706 and JP-B-2-18336. There is. However, these compounds are inferior in flame-retardant performance as compared with the above-mentioned triaryl phosphates, and have no effect of improving the heat resistance of the resin composition.

[0006] Phosphoric esters having low volatility and heat resistance include those described in US Pat. No. 4,134,876, US Pat. No. 5,122,556, and JP-A-5-1079. There is a condensed phosphate represented by the following general formula (5) having a substituent. But,
These compounds are resinous solids or solids, and are inferior in dispersibility and moldability in resins, and inferior in flame retardancy to triaryl phosphates.

[0007]

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(In the formula, Ar is an aryl group having a substituent other than hydrogen at the 2- and 6-positions.) On the other hand, an aryl group having an alkyl group at the 2- and 6-positions and a substituent at least at the 6-position It has been clarified that a condensed phosphoric ester represented by the following general formula (4), which has both aryl groups having no aryl group in the molecule, has excellent properties to solve the above-mentioned problem (Japanese Patent Application No. Hei 10-284,197). 7-46777).

[0009]

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Wherein n is an integer of 1 to 10, R is a divalent aromatic group represented by the general formula (1),
r4 is each independently represented by the general formulas (2) and (3)
A monovalent aromatic group derived from phenols, at least one of which has the same or different alkyl group having 1 to 4 carbon atoms at the 2nd and 6th positions, and at least one has no substituent at the 6th position. When n is 2 or more, a plurality of Ar4 may be the same or different. In other words, this compound has low volatility, does not exude from the resin, has a small decrease in heat resistance of the resin composition, and can be handled as a liquid, so that it has excellent dispersibility in a resin and molding processability, and excellent flame retardancy. Has performance. Therefore, a method for selectively producing the phosphate represented by the general formula (4) has been desired.

The method for producing these condensed phosphoric esters is as follows: (A) Phosphorus oxyhalide and monohydric phenols and dihydric phenols shown in JP-B-62-25706 are charged together, and the reaction is carried out. And (B) reacting a monohydric phenol with a phosphorus oxyhalide and then adding a dihydric phenol as described in JP-B-54-32818 and JP-A-5-1079. (C) A method of reacting a phosphorus oxyhalide with a dihydric phenol and then adding a monohydric phenol to complete the reaction as disclosed in JP-A-63-227632 and the like. ing.

However, in the methods (A) and (B), the product has many by-products of triaryl phosphates except when all monohydric phenols are compounds having a substituent at the ortho position. The problem of volatilization during molding becomes apparent. On the other hand, as a result of the study of the present inventors, in the method (C), the reaction rate of the monohydric phenol having no substituent is extremely higher than that of the monohydric phenol having the substituent at the 2-position and the 6-position. ,
Condensed phosphoric acid esters containing no monohydric phenols having substituents at the 2- and 6-positions are likely to be formed, and it is difficult to complete the reaction. Reaction of a monohydric phenol having a substituent at the 2- and 6-position with a monohydric phenol having no substituent, and for example, n of the general formula (4) It has been found that disproportionation reaction is likely to occur when two molecules of the compound of n = 1 produce a triaryl phosphate of n = 0 and a compound of n = 2.

[0013]

The present invention has both an aryl group having an alkyl group at the 2-position and the 6-position and an aryl group having no substituent at the 6-position represented by the general formula (4). It is an object of the present invention to provide a method for selectively producing a condensed phosphate ester useful as an additive for a synthetic resin.

[0014]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, have found that the reaction step is reduced to three.
When the synthesis is performed under specific conditions by dividing into stages, triaryl phosphate and heat resistance may be reduced.
Condensed phosphate ester containing no aryl group having an alkyl group at the 6th and 6th positions in the molecule, and at least one aryl group having no substituent at the 6th position in the molecule, which causes reduction in moldability. It has been found that by-products of condensed phosphoric acid esters that do not contain can be suppressed, and that the target product can be selectively and efficiently produced, and the present invention has been completed.

That is, the present invention is as follows. 1. A first reaction step of performing a condensation reaction of phosphorus oxyhalide and one or more dihydric phenols represented by the following general formula (1) under a Lewis acid catalyst, and HO-R-OH (1 (Wherein, R is a divalent aromatic group represented by the following formula 7)

[0016]

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(In the formula, A represents a bond, divalent S, a sulfone group, or an alkylidene group or alkylene group having 1 to 6 carbon atoms. X and Y each independently represent a 1 to 4 carbon atom. An alkyl group, and x and y are each independently an integer of 0 to 4.) The product of the first reaction step and one or more kinds of 2-positions represented by the following general formula (2) And a second reaction step of performing a condensation reaction of a phenol having an alkyl group at the 6-position,

[0018]

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(Wherein, R1 and R2 are each independently an alkyl group having 1 to 4 carbon atoms, and R3 to R5 are each independently a hydrogen or an alkyl group having 1 to 20 carbon atoms.) A third reaction step of performing a condensation reaction between the product of the reaction step and one or more phenols having no substituent at the 6-position represented by the following general formula (3);

[0020]

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(Wherein, R 6 to R 9 are each independently hydrogen,
It is an alkyl group having 1 to 20 carbon atoms, an aryl group, an alkoxy group, or a hydroxyl group. ) A purification step for removing or deactivating the Lewis acid catalyst, and the raw material charge composition in the first reaction step is 1.5 to 10 phosphorus oxyhalide per mole of dihydric phenol.
Moles, 10 ^-8 to 10 ^-1 mole of the Lewis acid catalyst, and alkyl groups at the 2- and 6-positions in the second reaction step with respect to 1 mole of the dihydric phenol charged in the first reaction step. A method for producing a condensed phosphoric acid ester represented by the following general formula (4), wherein the amount of phenols to be charged is 1 to 3 mol, and the operating temperature is kept at 200 ° C. or lower throughout all steps.

[0022]

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Wherein n is an integer of 1 to 10, R is a divalent aromatic group represented by the general formula (1),
r4 is independently represented by the general formulas (2) and (3)
Monovalent aromatic groups derived from phenols, at least one of which has the same or different alkyl group having 1 to 4 carbon atoms at the 2 and 6 positions, and at least one of which has a substituent at the 6 position Is an aromatic group having no When n is 2 or more, a plurality of Ar4 may be the same or different. ) 2. The amount of the phenols having alkyl groups at the 2- and 6-positions in the second reaction step is controlled by controlling the ratio of the aryl groups having the alkyl groups at the 2- and 6-positions contained in the condensed phosphate ester. The method for producing the condensed phosphoric acid ester according to the above-mentioned item 1, which is characterized in that: 3. In the second reaction step and / or the third reaction step,
The method for producing a condensed phosphoric ester according to the above item 1 or 2, further comprising adding a Lewis acid catalyst. 4. The condensed phosphoric acid ester of the above 1, 2, or 3, wherein the phenol having an alkyl group at the 2-position and the 6-position used in the second reaction step is 2,6-xylenol and / or 2,4,6-trimethylphenol. Manufacturing method. 5. The method for producing a condensed phosphoric ester according to the above 1, 2, 3 or 4, wherein the phenol having no substituent at the 6-position used in the third reaction step is phenol and / or cresol. 6. Production of the condensed phosphoric acid ester of the above 3, wherein the Lewis acid catalyst used in the first reaction step is anhydrous magnesium chloride, and the Lewis acid catalyst added in the second reaction step and / or the third reaction step is anhydrous aluminum chloride. Method. 7. The amount of the Lewis acid catalyst added in the second reaction step and / or the third reaction step is in the range of 10-3 to 10-1 mol per 1 mol of the dihydric phenols charged in the first reaction step, and The total amount of the Lewis acid catalyst used throughout the first reaction step through the third reaction step is in the range of 5 × 10 −3 to 2 × 10 −1 mol based on 1 mol of the dihydric phenol charged in the first reaction step. The method for producing the condensed phosphoric ester according to the above 3 or 6. 8. The first reaction step, the second reaction step, the third reaction step, and all the production steps of the purification step are performed at 180 ° C. or lower,
A method for producing 2, 3 or 4 condensed phosphate esters.

Hereinafter, the present invention will be described in detail. The method for producing a condensed phosphate according to the present invention is represented by, for example, the following reaction formula.

[0025]

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(Wherein, n is an integer of 1 to 10, X is a halogen element, HO-R-OH is a dihydric phenol represented by the general formula (1). R'OH is represented by the general formula (2). Phenols having alkyl groups at the 2- and 6-positions, R "OH is a phenol having no substituent at the 6-position represented by the general formula (3), and R 'and R" are Ar in the formula (4)
1 to Ar4. Examples of the phosphorus oxyhalide which is a raw material of the first reaction step of the present invention include phosphorus oxychloride, phosphorus oxychloride phosphorus,
Examples include phosphorus oxybromide, phosphorus oxybromide fluoride, and phosphorus oxybromide chloride, with phosphorus oxychloride being particularly preferred.

Examples of the dihydric phenol represented by the general formula (1), which is a raw material of the first reaction step of the present invention, include catechol, resorcinol, hydroquinone, biphenyl-3,3'-diol, biphenyl-4, Examples include 4′-diol, bisphenol A, bisphenol F, bisphenol S, and 2,2 ′, 6,6′-tetramethylbisphenol A, but hydroquinone, resorcinol, bisphenol A, and bisphenol S are preferred, and bisphenol A is preferred. Particularly preferred.

Examples of the phenols having an alkyl group at the 2-position and the 6-position represented by the general formula (2) used in the second reaction step of the present invention include 2,6-xylenol and 2-phenol.
Methyl-6-ethylphenol, 2-methyl-6-n-propylphenol, 2-methyl-6-isopropylphenol, 2-methyl-6-nbutylphenol, 2-methyl-6-tbutylphenol, 2,6-diethylphenol , 2-ethyl-6-isopropylphenol, 2
-Ethyl-6-tbutylphenol, 2,6-di-n-propylphenol, 2,6-diisopropylphenol,
2,6-di-t-butylphenol, 2,4,6-trimethylphenol, 2,6-dimethyl-4-ethylphenol, 2,6-dimethyl-4-npropylphenol,
2,6-dimethyl-4-isopropylphenol, 2,
6-dimethyl-4-nbutylphenol, 2,6-dimethyl-4-tbutylphenol, 2,4,6-triethylphenol, 2,4,6-trinpropylphenol, 2,4,6-triisopropyl Phenol, 2,
4,6-tri-t-butylphenol, 2,3,4,6-tetramethylphenol, 2,3,5,6-tetramethylphenol, 2,3,4,5,6-pentamethylphenol and the like. , 2,6-xylenol and 2,
4,6-trimethylphenol is particularly preferred.

Alkyl groups at the 2- and 6-positions of phenols are sterically hindered during the dehydrohalogenation condensation reaction. Therefore, the higher the bulk, the lower the reaction rate. Becomes The phenol used in the third reaction step of the present invention is not particularly limited as long as the 6-position of the aromatic ring is hydrogen, and phenol, cresol, ethylphenol, alkylphenols such as 3,5-dimethylphenol, phenylphenol, In addition to phenols having an aromatic substituent such as cumylphenol, phenols having an ether bond and dihydric phenols are also included. Among these, particularly preferred compounds are phenol and cresol.

The method for producing the condensed phosphoric acid ester of the present invention comprises:
It may be carried out without a solvent or in the presence of a solvent such as xylene. It is also preferable to use a part of the product as a solvent. The charged composition in the first reaction step is 1.5 to 10 mol, preferably 1.7 to 8 mol, more preferably 1.8 to 5 mol, of phosphorus oxyhalide per mol of dihydric phenol. The smaller the proportion of phosphorus oxyhalide, the larger the value of n in the general formula (4). If the amount of phosphorus oxyhalide is 1.5 moles or less relative to 1 mole of dihydric phenol, the reaction product gels. In addition, when phosphorus oxyhalide is used in an amount of at least twice the amount of the dihydric phenol, unreacted oxyhalide is added after the completion of the first reaction step in order to suppress by-products of triaryl phosphate in the second and subsequent reaction steps. It is preferable to remove phosphorus halide by means such as distillation.

In the method for producing a condensed phosphate according to the present invention, the composition of the product can be controlled by the amount of the phenol having an alkyl group at the 2-position and the 6-position in the second reaction step. That is, the phenols are charged in a range of 1 to 3 times the moles of the dihydric phenols charged in the first reaction step, so that the alkyl groups at the 2- and 6-positions contained in the product molecule. It can be arbitrarily produced from a small proportion to a large proportion of aryl groups. Above all, the charge ratio for obtaining a product suitable for a flame retardant is preferably in the range of 1.2 to 2.5 times. At less than the equivalent mole, a condensed phosphate ester containing no aryl group having an alkyl group at the 2- and 6-positions is formed, and the flame-retardant properties and other performances are reduced. A condensed phosphoric ester in which all the aryl groups have an alkyl group at the 2-position and the 6-position is formed to increase the viscosity or gel.

In the third reaction step, the amount of phenols charged is equivalent to the amount of unreacted halogen atoms bonded to phosphorus at the end of the second reaction step, or an excess amount. In the present invention, in the second reaction step, the phenols having an alkyl group at the 2-position and the 6-position suppress the disordered reaction to the molecule containing phosphorus due to the steric hindrance effect. For this purpose, the reaction temperature needs to be 200 ° C. or lower, preferably 180 ° C. or lower, more preferably 160 ° C. or lower. The lower limit of the reaction temperature is preferably 50 ° C or higher, more preferably 60 ° C or higher. If the temperature is lower than 50 ° C., the progress of the reaction becomes slow, and it is difficult to complete the reaction.

In the third reaction step, the above-mentioned transesterification reaction and disproportionation reaction occur in parallel. Since these side reactions are more likely to occur as the reaction temperature increases, the reaction temperature must be 200 ° C. or lower in the third reaction step, preferably 180 ° C. or lower, more preferably 160 ° C. or lower. To complete. The lower limit of the reaction temperature is preferably 50 ° C or higher, more preferably 60 ° C or higher. If the temperature is lower than 50 ° C., the progress of the reaction becomes slow, and it is difficult to complete the reaction. On the other hand, also in the third reaction step, the reaction rate is low due to steric hindrance of the substituent of the product of the second reaction step. To this end, a Lewis acid catalyst is added in the first reaction step, and the second reaction step and / or the third
It is preferable to add a catalyst in the reaction step.

Examples of the Lewis acid catalyst include aluminum chloride, titanium tetrachloride, iron chloride, magnesium chloride, tin chloride, zinc chloride and antimony pentachloride.
In the first reaction step, magnesium chloride having high reaction selectivity is preferable. In addition, the second reaction step and / or the third reaction step
As an additional catalyst in the reaction step, highly active aluminum chloride is preferable.

If the amount of the catalyst is small, there is no effect, and if it is large, the transesterification reaction and the disproportionation reaction are promoted. The catalyst used in the first reaction step is preferably in the range of 10 ^-3 to 10 ^-1 mol per mol of charged dihydric phenols, and is preferably 5 × 10 10 ^-1 mol.
The range of ^{-3 to} 5 × 10 ^-2 mol is more preferable. The amount of the catalyst added in the second reaction step and / or the third reaction step is 10 to 10 mols per 1 mol of the dihydric phenol charged in the first reaction step.
^-3 to 10 ^-1 mol, and the total amount of the catalyst used in the first to third reaction steps is 5 × 10 ^-3 to 2 × 10 ^-3 to 1 mol of the dihydric phenol charged in the first reaction step. ×
It is preferred to be in the range of 10 ^-1 mole.

After completion of the third reaction step, the crude phosphate is
If necessary, unreacted phenols are removed by distillation or the like. In this step, however, reactions such as transesterification and disproportionation occur at high temperatures.
It is necessary to maintain the temperature at or below 180 ° C, preferably at or below 180 ° C, more preferably at or below 160 ° C. The lower limit of the operating temperature is preferably 100 ° C. or higher, more preferably 120 ° C.
° C or higher. If it is lower than 100 ° C., it is difficult to remove phenols.

The obtained crude phosphate removes residual halogen in the purification step and removes or deactivates the Lewis acid catalyst. The purification method is not particularly limited, but pure water, alkaline water, etc. are added, and the mixture is stirred and washed to decompose the Lewis acid catalyst, extract the catalyst metal and residual halogen into the aqueous phase, and then separate the aqueous phase. The drying method is generally used. Products that do not contain Lewis acid catalyst after the purification process
It is thermally stable and hardly volatilizes, decomposes or denatures even at 300 ° C.

[0038]

The present invention will be described below in detail with reference to examples. The analytical methods used in the examples are shown below. <Quantitative determination of product> Composition by degree of condensation n: GPC (gel permission chromatography) device Tosoh LC 8020 series Column Tosoh TSKgel G2000HXL 2 Tosoh TSKgel G3000HXL 1 in-line Solvent THF flow = 1 ml / min Detector UV λ = 254 nm 200-fold dilution 5 μl Absolute standard curve method Composition of dimer (n = 1 component): HPLC (liquid chromatography) device Shimadzu LC-1OA column Tosoh TSKgel ODS-80T Solvent Methanol / water = 90/10 flow = 0.5 ml / Minute detector UV λ = 254 nm sample methanol 100-fold dilution 10 μl area ratio <identification of components> measuring device: LC-MS (Hitachi API type) column Tosoh TSKgel ODS-80T solvent methanol / water = 95/5 fl w = 1 ml / min Sample methanol 100-fold dilution 10μl ionization drift voltage 750 atomization chamber 280 ° C. desolvation chamber 350 ° C. measurement range m / e 200 to 1000

[0039]

Example 1 Bisphenol A (114 g, 0.5 mol), phosphorus oxychloride (192 g, 1.25 mol), and anhydrous magnesium chloride (1.4 g, 0.015 mol) were mixed with a 500 ml four-necked stirrer / reflux tube. The flask was charged and reacted at 70 to 140 ° C. for 4 hours under a nitrogen stream to perform a first reaction step. After the completion of the first reaction step, the flask was evacuated to a pressure of 200 mmHg or less by a vacuum pump while maintaining the reaction temperature, and unreacted phosphorus oxychloride was collected by a trap. Then, the flask was cooled to room temperature, and 122 g (1.0 mol) of 2,6-xylenol and 2.0 g (0.015 mol) of anhydrous aluminum chloride were added.
The mixture was heated to 0 ° C. and reacted for 4 hours to perform a second reaction step. The flask was then cooled to room temperature and phenol 94
g (1 mol) and heated to 100 ° C. to 150 ° C.
Hold for a time to complete the reaction. (Third reaction step) The pressure was reduced to 1 mmHg at the same temperature, and unreacted phenols were distilled off. Hydrogen chloride gas generated during the reaction was collected by an aqueous sodium hydroxide solution, and the amount of the generated hydrogen chloride gas was measured by neutralization titration to monitor the progress of the reaction.

After the produced crude phosphate was washed with distilled water, the solid content was removed by filter paper (# 131 manufactured by Advantech Co.). Vacuum dried to give a pale yellow clear reactant 35
4 g were obtained. Table 1 shows the charged composition, and Table 3 shows the analysis results of the reactants. Also, the GPC spectrum of the product and the HPL
The C spectrum is shown in FIGS.

[0041]

Examples 2 to 5 In the same manner as in Example 1, the reaction was carried out at the charged composition and the reaction temperature shown in Table 1 to obtain pale yellow transparent reactants. The results of analysis of the reactants are shown in Table 3.

[0042]

Example 6 The first reaction step was carried out using the same apparatus, preparation and reaction conditions as in Example 1. Then, the flask was cooled to room temperature, 122 g (1.0 mol) of 2,6-xylenol was added, and the mixture was heated to 100 to 160 ° C. and reacted for 6 hours (second reaction step). Then, the flask was cooled to room temperature, and 220 g (1 mol) of nonylphenol and 2.0 g (0.015 mol) of anhydrous aluminum chloride were added.
The reaction was heated to 00 ° C. to 160 ° C. and maintained for 4 hours to complete the reaction (third reaction step). The same purification treatment as in Example 1 was performed to obtain a pale yellow transparent reaction product. The results of analysis of the reactants are shown in Table 3.

[0043]

Comparative Example 1 The first reaction step was performed under the same apparatus, preparation and reaction conditions as in Example 1. Then, the flask was cooled to room temperature, and 122 g (1.0 mol) of 2,6-xylenol, 94 g (1 mol) of phenol and 2.0 g (0.015 mol) of anhydrous aluminum chloride were added.
The reaction was completed by heating at 50 ° C. for 6 hours. The same purification treatment as in Example 1 was performed to obtain a pale yellow transparent reaction product. Table 2 shows the charged composition, and Table 3 shows the results of analysis of the reactants. As shown in Table 3, the heat resistance is reduced by 2
30% by weight of a condensed phosphoric ester (compound 0) containing no aryl group containing an alkyl group at the 1-position and 6-position in the molecule
By-product.

[0044]

COMPARATIVE EXAMPLE 2 Except that 100 g (0.65 mol) of phosphorus oxychloride was used, the first apparatus was used under the same reaction conditions as in Example 1 to obtain the first.
A reaction step was performed. Then, the same amount of 2,6-
When xylenol and aluminum chloride were charged and the second reaction step was performed, the contents of the flask became gel-like,
It became difficult to continue the reaction.

[0045]

Comparative Example 3 The first reaction step was carried out using the same apparatus, preparation and reaction conditions as in Example 1. The flask was then cooled to room temperature and 195 g (1.6 mol) of 2,6-xylenol and 2.0 g (0.015
Mol), and the mixture was heated to 100 to 160 ° C. and reacted for 4 hours (second reaction step). Then, the flask was cooled to room temperature, and 38 g (0.6 mol) of phenol was added.
The reaction was completed by heating the mixture to a temperature in the range of from 0 ° C. to 170 ° C. for 4 hours. When the pressure was reduced to 1 mmHg at the same temperature and unreacted phenols were distilled off, the product became viscous and could not be purified.

[0046]

Comparative Example 4 The first reaction step was carried out using the same apparatus, preparation and reaction conditions as in Example 1. Then, the flask was cooled to room temperature, 122 g (1.0 mol) of 2,6-xylenol was charged, the temperature was raised, and the reaction was carried out at 220 ° C. for 3 hours.
The flask was then cooled to room temperature and cresol 108 g
(1 mol), and the temperature was raised from 140 ° C. and maintained at 220 ° C. for 2 hours to complete the reaction (third reaction step). The pressure was reduced to 1 mmHg at the same temperature, and unreacted phenols were distilled off. Purification was carried out in the same manner as in Example 1 to obtain a brownish viscous reaction product. Table 2 shows the charged composition, and Table 3 shows the results of analysis of the reactants. As shown in Table 3, 25% by weight of triaryl phosphate was by-produced.

[0047]

Comparative Example 5 13.3 g of aluminum chloride as a catalyst
The reaction was carried out in the same manner as in Example 1 except that (0.1 mol) was used. Most of the product was in the form of a resin insoluble in a solvent such as methanol, and could not be washed and purified.

[0048]

[Table 1]

[0049]

[Table 2]

[0050]

[Table 3]

[0051]

According to the present invention, a condensed phosphoric ester having both an aryl group having an alkyl group at the 2-position and the 6-position and an aryl group having no substituent at the 6-position in the molecule can be selectively produced. Can be manufactured.

[Brief description of the drawings]

FIG. 1 is a GPC spectrum of a reaction product obtained in Example 1.

FIG. 2 is an HPLC spectrum of a reaction product obtained in Example 1.

[Description of References] In FIG. 1, 0 signal of triaryl phosphate 1 signal of condensed phosphate (n = 1) 2 signal of condensed phosphate (n = 2) 3 signal of condensed phosphate (n = 3) 4 2. Signal of condensed phosphate (n ≧ 4) In FIG. 2, 0 triaryl phosphate 1 compound 1 (1 having substituents at the 2- and 6-positions in the molecule)
Phosphoric acid esters containing one divalent phenol residue. 2) Compound 2 (1 having substituents at the 2- and 6-positions in the molecule)
Phosphoric acid esters containing two divalent phenol residues. 3) Compound 3 (1 having substituents at the 2- and 6-positions in the molecule)
Phosphoric acid ester containing three divalent phenol residues. )

Claims (8)

(57) [Claims] 1. A method according to claim 1, wherein a phosphorus oxyhalide and one or two or more compounds represented by the following general formula (1) are used in the presence of a Lewis acid catalyst.
A first reaction step of performing a condensation reaction of a polyhydric phenol, and HO—R—OH (1) (wherein R is a divalent aromatic group represented by the following chemical formula 1) (In the formula, A represents a bond, divalent S, a sulfone group, an alkylidene group having 1 to 6 carbon atoms, or an alkylene group.
And Y are each independently an alkyl group having 1 to 4 carbon atoms, and x and y are each independently an integer of 0 to 4. A) a second reaction step of performing a condensation reaction between the product of the first reaction step and one or more phenols having alkyl groups at the 2- and 6-positions represented by the following general formula (2); Embedded image (In the formula, R1 and R2 are each independently an alkyl group having 1 to 4 carbon atoms, and R3 to R5 are each independently hydrogen or an alkyl group having 1 to 20 carbon atoms.) A third reaction step of performing a condensation reaction between the product and one or more phenols having no substituent at the 6-position represented by the following general formula (3): (Wherein, R 6 to R 9 are each independently hydrogen, having 1 to 2 carbon atoms)
And 0 is an alkyl group, an aryl group, an alkoxy group, or a hydroxyl group. A) a purification step for removing or deactivating the Lewis acid catalyst, and wherein the raw material charge composition in the first reaction step is 1.5 to 10 mol of phosphorus oxyhalide, Acid catalyst 10-8-1
0-1 mole, and 1 mole of the dihydric phenol charged in the first reaction step, in the second reaction step.
The charge amount of the phenol having an alkyl group at the 2-position and the 6-position is 1 to 3 mol, and the operating temperature is 2 throughout all the steps.
The following general formula (4) characterized in that the temperature is maintained at 00 ° C. or lower.
A method for producing a condensed phosphate represented by the formula: Embedded image (In the formula, n is an integer of 1 to 10, and R is a general formula (1)
Wherein Ar1 to Ar4 are each independently a phenol represented by the general formulas (2) and (3)
A monovalent aromatic group derived from the group, at least one of which has the same or different alkyl group having 1 to 4 carbon atoms at the 2 and 6 positions, and at least one has a substituent at the 6 position. There are no aromatic groups. When n is 2 or more, a plurality of Ar4 may be the same or different. ) 2. The ratio of the aryl group having an alkyl group at the 2-position and the 6-position contained in the condensed phosphate ester, depending on the charged amount of the phenol having an alkyl group at the 2-position and the 6-position in the second reaction step. The method for producing a condensed phosphoric acid ester according to claim 1, wherein 3. The method for producing a condensed phosphate according to claim 1, wherein a Lewis acid catalyst is added in the second reaction step and / or the third reaction step. 4. The phenol having an alkyl group at the 2-position and 6-position used in the second reaction step is 2,6-xylenol and / or 2,4,6-trimethylphenol.
A method for producing the condensed phosphoric acid ester according to claim 1, 2 or 3. 5. The method for producing a condensed phosphate according to claim 1, wherein the phenol having no substituent at the 6-position used in the third reaction step is phenol and / or cresol. 6. The Lewis acid catalyst used in the first reaction step is anhydrous magnesium chloride, and the Lewis acid catalyst added in the second reaction step and / or the third reaction step is anhydrous aluminum chloride. A method for producing the condensed phosphoric acid ester according to the above. 7. In the second reaction step and / or the third reaction step,
The amount of the Lewis acid catalyst to be added depends on the amount charged in the first reaction step 2
10 moles per mole of polyhydric phenol^-3-10^-1Mole range
And used from the first reaction step to the third reaction step.
The total amount of Lewis acid catalyst used is 2
5 × 10 ^-3~ 2 × 10^-1Mo
7. The condensed phosphate ester according to claim 3, which is in the range of
Manufacturing method. 8. All the production steps of the first reaction step, the second reaction step, the third reaction step and the purification step are performed at 180 ° C. or lower.
A method for producing the condensed phosphoric acid ester according to claim 1, 2, 3, or 4.