JP3366232B2 - Powdering method of aromatic phosphates - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for powdering aromatic phosphates. More specifically, the present invention relates to a method for easily powdering an aromatic phosphate useful as a flame retardant or a plasticizer for synthetic resins from an oily substance after production without subjecting it to a special purification means.

[0002]

BACKGROUND OF THE INVENTION Aromatic phosphates are used as flame retardants and plasticizers for synthetic resins.
The resin can be provided with flame retardancy, thermal stability, and / or good moldability. For this reason, the aromatic phosphates have been used as useful additives for various resins.

However, aromatic phosphates are
As long as you try to get this by normal industrial manufacturing methods,
By-products of homologues or analogues are unavoidable, and most of the crystalline substances are obtained as oily substances. Further, if the oily substance is left to stand for a long time, a part or the whole is solidified at the time of use, and it is necessary to heat and dissolve it for use. When aromatic phosphates are used as flame retardants or plasticizers, powders (crystalline powders) are more advantageous than oily substances in terms of packaging and transportation as products.

Conventionally, in order to obtain crystals from an oily substance of aromatic phosphates, it has been necessary to carry out a high-cost purification treatment such as a recrystallization method (crystallization method) using an organic solvent or a fractional distillation method. . Therefore, the present inventors have proposed aromatic phosphates having a purity of about 90% or more, which are difficult to be powdered, to
The inventors have found a simple, inexpensive, and continuous solidification powder method by applying stress with a kneader at a temperature of 5 to 100 ° C. or lower than its melting point (see JP-A-9-87290).

On the other hand, aromatic phosphates obtained by an industrial production method have high viscosity and tackiness in the supercooling region below the melting point thereof due to by-products such as homologues and analogues or additives such as catalysts. There are many. When such an oily substance of aromatic phosphates is supplied to the kneader at a temperature below its melting point, the oily substance adheres to the heat transfer surface of the kneader,
As a result, the cooling ability of the kneader is remarkably impaired, which causes a problem that the kneader cannot be continuously operated for a long time. Further, when the oily substance of the aromatic phosphates supplied to the kneader is cooled to the melting point or lower, there is a problem that the viscosity of the oily substance clogs in the cooler.

[0006]

The inventors of the present invention have made various studies on such a method of continuously solidifying and powdering an aromatic phosphate by a kneader for a long time, and as a result, the oily substance of the aromatic phosphate has been solidified. It was found that continuous solidification and pulverization for a long period of time is possible by supplying a kneader together with the powder or particles of (1) (for example, the powder of the aromatic phosphate) and applying stress to the kneader, and arrived at the present invention.

[0007] Thus, according to the present invention, the temperature-controllable kneader, an oil with a purity of 85% or more aromatic phosphates, the aroma of 1 to 500 wt% with respect to oil
Aromatic oils of the same or different type as oils of group phosphates
Normally used with flame retardants for phosphates or resins
Supplied with a solid powder or particles of the additives added ,
There is provided a method for pulverizing aromatic phosphates, which comprises applying stress at a temperature 5 to 100 ° C. lower than the melting point of the aromatic phosphates to solidify and pulverize the aromatic phosphates.

[0008]

DETAILED DESCRIPTION OF THE INVENTION The present invention is preferably used to obtain powdered aromatic phosphates by a continuous process following the synthesis of aromatic phosphates. The oily substance of aromatic phosphates that can be used in the present invention is an oily substance of aromatic phosphates having a purity of about 85% or more obtained by an industrial production method, for example, the compound represented by the general formula (I):

[0009]

[Chemical 2]

(Wherein R ¹ and R ² are the same or different and are a lower alkyl group, R ³ and R ⁴ are the same or different and are a hydrogen atom or a lower alkyl group, Y is a bond,
_{CH 2 -, - C (CH} 3) 2 -, - S -, - SO 2 -,
The compound represented by -O-, -CO- or -N = N- group, k is 0 or 1, m is an integer of 0-4, and n is an integer of 0-10.

The "lower alkyl group" of the substituents R ¹ , R ² , R ³ and R ⁴ of the general formula (I) is a linear or branched alkyl group having 1 to 6 carbon atoms. Specifically, methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, tert-butyl, n-pentyl, iso-pentyl, tert-pentyl, neo-pentyl. ,
Examples of n-hexyl and the like include a methyl group for R ¹ and R ² , and a hydrogen atom for R ³ and R ⁴ . The compound of the general formula (I) has the following formula when n = 1:

[0012]

[Chemical 3]

(Wherein R ¹ , R ² , R ³ , R ⁴ , Y, k
And m are preferably aromatic diphosphates represented by formula (I), and tetrakis (2,6-dimethylphenyl) m-phenylenebisphosphate (hereinafter,
Compound (1)), tetrakis (2,6-dimethylphenyl) p-phenylene bisphosphate, tetrakis (2,6-dimethylphenyl) 4,4'-diphenylene bisphosphate, and the like are exemplified. It is not limited.

The oily substance of the aromatic phosphates of the general formula (I) of the present invention can be synthesized, for example, by the production method described in JP-A-5-1079. That is, an aromatic monohydroxy compound and phosphorus oxyhalide are reacted in the presence of a Lewis acid catalyst in an organic solvent to obtain a diarylphosphorohalidate, and then this product is reacted with an aromatic dihydroxy compound by a Lewis acid catalyst. And the catalyst and the organic solvent are removed from the resulting reaction mixture to obtain an aromatic phosphate represented by the general formula (I) as an oil.

The purity of the aromatic phosphates obtained here is about 90 to 99% due to by-products such as multimers, monomers and intermediates although it varies depending on the raw materials, the synthesis method and the conditions. If the purity of the aromatic phosphates is 90% or more, it is not always necessary to supply a solid powder or particles as in the method of the present invention. However, it is easier to control the temperature of the kneader and the processing time can be shortened by supplying solid powder or particles. The purity of the aromatic phosphates that can be used in the present invention is about 85% or higher, preferably about 90% or higher, more preferably about 92% or higher. However, the value of the above-mentioned purity is not strictly limited. If the purity is about 85% or higher,
It can be easily and solidified into powder in a short time.

“Solid powder or particles” according to the invention
And has a nucleating agent effect that becomes crystal nuclei and promotes crystallization, a cooling effect that gradually cools the heat of solidification, an effect that suppresses the stickiness of oily substances, etc., and finally solidifies and powders the aromatic phosphates. It means something that has a promoting effect. The smaller the solid powder or particle size, the larger the surface area, and the greater the effect of contacting the oily substance of aromatic phosphates and the wall surface inside the kneader, and the effect of suppressing the tackiness of the oily substance can be expected. preferable.

As the solid powder or particles which can be used in the present invention, generally, compound powder or particles of the same kind as the oily substance of aromatic phosphate can be preferably used.
Further, powders or particles of different aromatic phosphates can be used as long as they do not affect solidification and powdering. In this case, a blended product of a plurality of aromatic phosphates can be obtained simultaneously with pulverization.

The solid powder or particles usable in the present invention include different flame retardants such as halogen flame retardants and inorganic flame retardants, antioxidants, ultraviolet absorbers, and the like.
Powders or particles of additives commonly used with resins for flame retardants, such as UV stabilizers, are desirable.

Examples of different flame retardants include tetrabromobisphenol A (TBA), decabromodiphenyl oxide, 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, hexabromobenzene (HB).
B), tris (2,3-dibromopropyl) isocyanurate (TAIC-6B), 2,2-bis (4-hydroxyethoxy-3,5-dibromophenyl) propane (TBA-EO) and decabromodiphenyl oxide ( Examples thereof include halogen-based flame retardants such as DBDPO) and inorganic flame retardants such as red phosphorus, tin oxide, antimony trioxide, zirconium hydroxide, barium metaborate, aluminum hydroxide and magnesium hydroxide.

The additives usually used for the resin together with the flame retardant include, specifically, 2,2'-methylenebis (4-methyl-6-t-butylphenol),
2,2'-methylenebis (4-ethyl-6-t-butylphenol), 4,4'-thiobis (3-methyl-6-
t-butylphenol), 4,4′-butylidenebis (3-methyl-6-t-butylphenol) and 3,
9-bis [1,1-dimethyl-2- [β-t-butyl-
4-hydroxy-5-methylphenyl) propionyloxy] ethyl] 2,4,8,10-tetraoxaspiro [5,5] undecane and other bisphenol antioxidants, 1,1,3-tris (2-methyl) -4-hydroxy-5-t-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, tetrakis-
[Methylene-3- (3 ', 5'-di-t-butyl-4'
-Hydroxyphenyl) propionate] methane and 1,3,5-tris (3 ', 5'-di-t-butyl-
4'-hydroxybenzyl) -S-triazine-2,
Polymeric phenolic antioxidants such as 4,6- (1H, 3H, 5H) trione, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10- (3,5- Di-t-butyl-4-hydroxybenzyl) -9,10-dihydro-9-oxa-10-
Phosphaphenanthrene-10-oxide, tris (2,4-di-t-butylphenyl) phosphite, cyclic neopentanetetraylbis (2,4-di-)
t-Butylphenyl) phosphite, cyclic neopentanetetraylbis (2,6-di-t-butyl-4)
Phosphorus-based antioxidants such as methylphenyl) phosphite and 2,2-methylenebis (4,6-di-t-butylphenyl) phosphite, aluminum bis (pt-butylbenzoate), bis (p-ethyl) Benjiriden)
Antioxidants such as sorbitol,

2,4-dihydroxybenzophenone,
Benzophenone-based UV absorption such as 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone and bis (2-methoxy-4-hydroxy-5-benzoylphenyl) methane Agent, 2- (2'-hydroxy-5'-
Methylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-di-t-butylphenyl) benzotriazole, 2- (2-hydroxy-3'-t-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-
t-butyl-methylphenyl) -5-chlorobenzotriazole and 2- {2'-hydroxy-3'-
(3 ", 4", 5 ", 6" -tetrahydrophthalimidomethyl) -5'-methylphenyl} benzotriazole, 2,2'-methylenebis {4- (1,1,3,3-)
Benzotriazole-based UV absorbers such as tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol} and cyanoacrylate-based UV absorbers such as ethyl-2-cyano-3,3'-diphenylacrylate UV absorbers, such as

[2,2'-thiobis (4-t-octylphenolate)]-n-butylamine nickel, nickel complex-3,5-di-t-butyl-4-hydroxybenzyl phosphoric acid monoethylate and nickel. UV stabilizers such as dibutyldithiocarbamate, Sa
nol LS-770 (manufactured by Sankyosha), Chimasso
Examples of the UV stabilizer include hindered amine light stabilizers such as rb 994LD (manufactured by Ciba Geigy), ADEKA STAB LA-57, LA-63, LA-68, LA-77 (all manufactured by Asahi Denka Co., Ltd.).

The amount of the solid powder or particles to be supplied in the present invention depends on the purity, viscosity, and oily substance of the aromatic phosphates.
It may vary depending on physical properties such as tackiness and wettability, the temperature of supply to the kneader and the characteristics of the apparatus used, and the blending ratio of the blended product. Further, the lower the temperature of the solid powder or particles to be supplied, the more the cooling effect is obtained, and the amount of the solid powder or particles to be supplied can be reduced, which is preferable. The amount of solid powder or particles to be fed is generally 1 to 500% by weight, preferably 20 to 300% by weight, more preferably 50 to 150% by weight based on the oily substance of aromatic phosphates.
% By weight. However, the value of the supply amount is not strictly limited. When the supply amount is in the range of 1 to 500% by weight, the kneaded material has low tackiness and can be prevented from adhering to the heat transfer surface, so that the kneader can be continuously operated for a long time.

In the present invention, a kneader generally used for kneading plastic materials can be used. The term “kneading” means that when several kinds of additives are mixed with a plastic material, the materials and the additives are simultaneously subjected to a decoupling force so that the additives are uniformly dispersed inside the material. The "stress addition" of the present invention is synonymous with "kneading" in that the temperature of the material supplied to the kneader is made uniform, and at the same time, a cutting force, that is, stress is applied to the material.

Generally, the kneader is a mixing roll, Σ
It is classified into a batch type such as a blade type kneader and an intensive mixer, and a continuous type such as a high speed twin-screw continuous mixer and an extruder type kneader. When these kneaders are used for the purpose of solidification as in the present invention, a continuous kneader capable of simultaneously pressing the produced solidified product is preferable. Further, the continuous type has a high processing capacity and is advantageous from the viewpoint of industrial use.

Particularly, the kneader which can be used in the present invention is a kind of extruder type kneader, has a strong decoupling force, has a high kneading effect, and can be continuously solidified and powdered, and is a kneader type kneader. Is suitable, but is not particularly limited to this as long as it is a model having a similar effect. The kneader is a heating mechanism such as an electric resistance type band heater, an aluminum casting heater or a dielectric heating method, and a heating or cooling mechanism such as circulating water or oil in a jacket portion provided in a cylinder and a pipe provided in a screw. It is possible to control the temperature inside the kneader.

Next, an example of an actual solidified powder process will be described with reference to FIGS. 1 and 2. FIG. 1 is a cross-sectional view of the kneader that can be used in the powdering method of the present invention in the direction of the rotation axis, and FIG. 2 is a cross-sectional view taken along the line AA in FIG. In the process, at least the oily substance of aromatic phosphate adjusted to a temperature suitable for solidification and pulverization is introduced into the raw material inlet (3) from the treatment can (1) through the raw material conveying system (2) including a valve and a pump. Liquid is sent. Here, the solid powder or particles are supplied from the hopper (12), charged into the raw material receiving port (3), and supplied to the kneader together with the oily substance of aromatic phosphate. Next, solidification and pulverization by stress application is continuously carried out in a kneading section (4) composed of a twin screw and a cylinder which are engaged while reversing each other, and finally, aromatic phosphates are discharged from the discharge port (5). Will be continuously discharged. A part of the discharged powder is pneumatically transported to the hopper (12) by an injection feeder (14) to which high-pressure air (HPA in the figure) is supplied, and passes through the powder feeder (13) to be a solid powder or particles. It is supplied to the kneader again. In addition,
Arrows FS and HPA in the figure indicate the flow of solid powder or particles and the flow of high pressure air, respectively.

In the above examples, the same kind of aromatic phosphate solidified and powdered as a solid powder or particles is used, but it is usually used together with a flame retardant for different aromatic phosphates, different flame retardants or resins. When using the additives to be added, those solid powders or particles may be fed to the hopper (12). The solid powder or particles can be supplied continuously or intermittently depending on the solidified powder state of the aromatic phosphates, or a combination of both.

It is effective that the kneading effect is high because the solid powder or particles are supplied at the same position as the oily substance of the aromatic phosphates as in the above example. However, the appropriate position of the solid powder or particle supply may differ depending on the kneader structure such as the shape of the screw, and the supply position of the solid powder or particle may be changed depending on the solidified powderization state. From this point of view, a kneader capable of changing the supply position of solid powder or particles is preferable.

However, simply kneading the aromatic phosphates while supplying solid powder or particles is not efficient, and it is desirable to control the inside of the kneader to a suitable temperature range. The optimum temperature range is the thermal physical properties of the aromatic phosphates that are solidified and powdered (heat of solidification, sensible heat, etc.)
In addition, the viscosity may vary depending on the viscosity, fluidity, frictional heat, etc. during kneading and the characteristics of the apparatus used. The temperature is generally 5 to 100 ° C lower than the melting point of the aromatic phosphates, preferably 10 to 70 ° C lower, more preferably 10 to 50 ° C lower. However, the temperature value is not strictly limited. Temperature is 5-100
In the range of ° C, appropriate stress is applied to the compound in the kneader, and complete solidification and shortening of solidification time can be achieved.

For controlling the temperature, the kneader is provided with a jacket (6) for heating or cooling the compound, that is, an oily substance of aromatic phosphates, around the cylinder and heating or cooling the inside as a screw. It is equipped with a possible screw (9). For example, in the case of cooling, the cooling liquid flows through the jacket (6) from the liquid supply port (7) to the liquid discharge port (8) to cool the compound inside the kneader container. Similarly, the screw (9) is supplied with the cooling liquid from the liquid supply port (10) formed at one end of the shaft, returns through the outward path of the center and returns at the other end of the shaft, and passes through the return path formed at the outer periphery of the outward path. Drainage port (1
The compound flowing in 1) and contacting the screw (9) is cooled. In addition, arrows FC and FW in the figure indicate the flow of the compound and the heating or cooling liquid, respectively.

The solidification time, that is, the residence time of the aromatic phosphates in the kneader is generally about 1 to 120 hours. By prolonging the residence time, it is possible to solidify and powder the aromatic phosphate having a lower purity. Become.

In the present invention, an oily substance of aromatic phosphates having a purity of about 85% or more is supplied to a temperature controllable kneader together with 1 to 500% by weight of solid powder or particles based on the oily substance to obtain an aromatic substance. 5 to 1 from the melting point of group phosphates
Stress is applied at a temperature as low as 00 ° C. to forcibly solidify and powder the aromatic phosphates. This is because the supply of solid powder or particles reduces the stickiness of the aromatic phosphate oil itself, and at the same time the solid powder or particles promotes crystallization, which further suppresses stickiness and reduces the heat transfer of the kneader. It is considered that this is because the adhesion to the surface can be prevented.

Therefore, the purity of the aromatic phosphates which can be solidified and powdered by a kneader without supplying solid powder or particles is 90% or more, more preferably 95%.
Although the above is required, by supplying solid powder or particles, it is possible to solidify and powder even aromatic phosphates having a lower purity. Further, due to the cooling effect of the solid powder or particles to be fed, when the oily substance of the aromatic phosphates is fed to the kneader, it can be fed at a higher temperature than when the solid powder or particles are not fed, so that clogging in the cooler is caused. You can prevent problems such as.

[0035]

EXAMPLES Next, the present invention will be described in detail with reference to examples, but these examples do not limit the scope of the present invention. Moreover, various physical properties were measured by the following test methods. Appearance: Visual observation Purity: Gel permeation chromatography Melting point: JIS standard K-0064 Viscosity: JIS standard K-2283 Heat of solidification: DSC (differential scanning calorimeter) method Specific heat: DSC (differential scanning calorimeter) method

Example 1 Tetrakis (2,6-dimethylphenyl) m-phenylene bisphosphate (Compound (1)) was used on an industrial scale according to Synthesis Example 1 described in JP-A-9-87290. Synthesized. That is, 2,6-xylenol and xylene were reacted in the presence of a magnesium chloride catalyst, phosphorus oxychloride was added, and the reaction was performed while removing the generated hydrochloric acid gas to obtain the compound (1). The obtained compound (1) contained trimers, intermediates and triesters as impurities.
The physical properties and structural formulas are shown below.

Appearance: Light yellow highly viscous liquid Purity: 94.0% Melting point: 92 ° C. Viscosity: 199 cP (90 ° C.), 491 cP (80 ° C.) Heat of solidification: 13 kcal / kg Specific heat: 0.40 (liquid 100 ° C.) , 0.28 (powder 2
5 ° C)

[0038]

[Chemical 4]

Kneader (manufactured by Satake Chemical Machinery Co., Ltd.,
NES-KO 280 type, φ280mm x 2100mm
× 2 axis, 46 rpm, material SUS304, inner hub # 2
00, cooling water temperature 32 to 33 ° C.), an oily substance of compound (1) (80 ° C.) at a rate of 200 kg / hour from the same inlet as a solid powder or particles of compound (1) ( (50 ° C.) was continuously supplied at a rate of 100 kg / hour (solid supply amount 50% by weight) to solidify the oil. As a result, it was possible to carry out continuous operation for 24 hours or more without the oily substance adhering to the screw and the cooling jacket. Table 1 shows the solidification conditions and the results. In the table, solid represents powder of compound (1).

Example 2 The procedure of Example 1 was repeated except that the oil temperature of the compound (1) was 90 ° C. and the powder feed rate was 200 kg / hr (solid feed rate 100% by weight). When the oily substance was solidified, continuous operation for 24 hours or more was possible. Table 1 shows the solidification conditions and the results.
Shown in.

(Comparative Example 1) An oily substance was solidified in the same manner as in Example 1 except that the powder was not supplied. When the oily substance adhered to the screw and the cooling jacket, the cooling effect was lost and it took about 4 hours. It became inoperable. Table 1 shows the solidification conditions and the results.

[0042]

[Table 1]

* 1: Supply amount (% by weight) of the powder of the compound (1) with respect to the supply amount of the oily substance of the aromatic phosphates * 2: Until the time when the defective solidification product is discharged from the discharge port (5) of the kneader Judging the continuous operating time as: ○ indicates that the kneader can be continuously operated for a long time, and × indicates that the kneader cannot be continuously operated for a long time.

[0044]

The present invention provides a kneader capable of controlling temperature,
Aromatic phosphate oils having a purity of about 85% or more,
It is supplied together with 1 to 500% by weight of solid powder or particles with respect to an oily substance, and the melting point of aromatic phosphates is 5 to 5%.
Stress is applied at a temperature lower by 100 ° C. to forcefully solidify the aromatic phosphates into powder. Therefore, conventionally, in the aromatic phosphates obtained by an industrial production method, particularly in the aromatic phosphates which have been difficult to continuously operate for a long time of the kneader due to high viscosity attached to the kneader heat transfer surface below its melting point. Also, it can be solidified and pulverized by continuous operation for a long time.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a kneader used for pulverization of the present invention in a rotation axis direction and a schematic view of an oily substance and solid powder or particle supply facility.

2 is a cross-sectional view taken along the line AA of the kneader body of FIG.

[Explanation of symbols]

1 processing can 2 Raw material transport system 3 Raw material reception 4 kneading section 5 outlets 6 jacket 7 Liquid supply port 8 drainage port 9 screws 10 Liquid supply port 11 drainage port 12 hoppers 13 Powder feeder 14 Injection feeder AA device cross section Flow of FC compound Flow of FW liquid FS Solid powder or particle flow HPA high pressure air

Continuation of the front page (56) Reference JP-A-9-87290 (JP, A) JP-A-5-1079 (JP, A) JP-A-58-27604 (JP, A) JP-A-9-183785 (JP , A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) C07F 9/12

Claims (4)

(57) [Claims] 1. A temperature controllable kneader with a purity of 85%.
The oily substance of the aromatic phosphates described above is used in an amount of 1 to 500% by weight of the oily substance of the aromatic phosphates.
Same or different aromatic phosphates or trees
It is characterized in that it is supplied together with a solid powder or particles of an additive commonly used for a fat together with a flame retardant, and stress is applied at a temperature 5 to 100 ° C. lower than the melting point of the aromatic phosphates to solidify the powder. A method for powdering aromatic phosphates. Wherein at least the solvent was continuously fed into a kneader oil aromatic phosphates after manufacture removal of the powdered method according to claim 1, characterized in that the solidified powdered. 3. Normally used with flame retardants for resins.
That solid powder or particulate additives, halogen-containing flame retardants, inorganic flame retardants, antioxidants, a powder or particles of the ultraviolet absorbers and ultraviolet stabilizers or al selection solids <br/> claims Item 3. The powdering method according to Item 1 or 2. 4. The aromatic phosphates are represented by the general formula (I): (In the formula, R ¹ and R ² are the same or different and are a lower alkyl group, R ³ and R ⁴ are the same or different and are a hydrogen atom or a lower alkyl group, Y is a bond, —CH ₂ —, —C
_{(CH 3) 2 -, -} S -, - SO 2 -, - O -, - CO-
Or -N = N-group, k of 0 or 1, m is 0 to 4 integer, n represents according to any one of claims 1 to 3 which is a compound represented by an integer) of 0 Powdering method.