JPS6094928A - Separation and recovery of brominated acenaphthylene condensate - Google Patents

Abstract

PURPOSE:To obtain the condensation product of the titled compound with simple operation, in high recovery, in powdery form, from the solution of the compound obtained by the bromination, condensation and dehydrobromination reactions of acenaphthene, by carrying out the reprecipitation using a 3-5C saturated aliphatic monohydric alcohol as the poor solvent. CONSTITUTION:A solution of the brominated acenaphthylene condensate having the units of formula I and formula II (n and n' are integer of 1-5) as the constituent elements and obtained by the bromination, condensation and hydrobromination reactions of acenaphthene is added to a 3-5C saturated aliphatic monohydric alcohol (preferably 1- or 2-propanol, 1- or 2-butanol, or 2-methyl-2-propanol) to effect the reprecipitation of the condensation compound. The amount of the alcohol is usually 1-20pts.vol., preferably 2-10pts.vol. based on 1pt.vol. of the above solution. The condensation product useful as a flame-retardant and anti- radiation agent for various inflammable resins can be separated and recovered by this process in the form of powder suitable for handling and rolling.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for separating and recovering a brominated acenaphthylene condensate as a powder from a solution obtained in its production process.

Brominated acenaphthylene condensate (hereinafter abbreviated as Con-BACN) is a compound with excellent flame retardancy and radiation resistance, and is blended into various flammable resins to make the resin flame retardant and radiation resistant. There is.

In addition, since it has a double bond in its molecule, it can be grafted onto resins by subjecting it to free radical generation treatment, and since it is a condensate, it has excellent compatibility with resins, so it can last for a long time. It is attracting attention as a compound that can maintain stable flame retardancy and radiation resistance. (Unexamined Japanese Patent Publication No. 56-
122862) An object of the present invention is to provide a method for separating and recovering Con-BACN as a powder from a solution containing Con-BACN.

Con-B A CN as used in the present invention is a compound containing at least one bromine in an aromatic ring, and brominated acenaphthene is formally condensed by Friedel-Crach reaction, resulting in a degree of condensation of 2. It refers to the above multimer, which subsequently becomes Co +i -B ACN through a dehydrobromination reaction.

That is, it is a condensate consisting of units represented by the general formula (1) or [fl] (in the formula, n and n' represent integers of 1 to 5), and its bonding mode is benzyl of acenaphthylene. 3'-11 (or 2), 4'-1 between the carbon at position carbon and the carbon at aryl position of acenaphthylene
1 (or 2), 7'-11 (or 2), 8'-
The following combinations are possible.

Those with a degree of condensation of 3 or more have an increased number of structural units due to the inclination of such bonds. The condensate as used in the present invention refers to a condensation product having a degree of condensation of 10 or less and having excellent compatibility with resin.

Con-BACN is generally produced by an aqueous bed reaction of bromination, condensation and debromination of acenaphthene.

That is, acenaphthene is brominated and condensed by adding bromine in the presence of a Lewis coordination catalyst in a halogenated hydrocarbon solvent, and the resulting halogenated acenanthene condensate is debrominated with a base such as caustic cauli-methanol. Manufactured by hydrogen reaction. The dehydrobromination reaction is carried out in a base-inert solvent such as caustic potash-methanol, ie, a halogenated hydrocarbon or aromatic hydrocarbon solvent.

Con-BACN obtained by these manufacturing processes
Methods for separating and recovering Con-BACN and CN from a solution include (1) evaporating and distilling off the solvent from the Con-BACN solution, and (2) adding the Con-BACN solution to a poor solvent and separating it by precipitation. There are several possible methods, but (1)
In the method described above, Con-'BACN is solidified into a resin, and Co
Since n-BACN cannot be processed as a powder, it is difficult to handle.

In addition, although this resin-like Con-B A CN can be used for practical purposes as it is, CoH-BAC
A small amount of solvent remains in H and is relatively difficult to remove. Therefore, the melting point of the obtained Con-BACN is 50°C to 80°C, which is 50°C to 70°C lower than that of the powder, and when the compound is kneaded with a resin on a roll, it may cause roll adhesion or the solvent may evaporate. It has the drawback of poor workability, such as corrosion of processing and molding machines due to thermal decomposition.

Therefore, the solvent in Con-BACH was removed and the Con-BACH
If -B A CN could be made into a powder with a higher melting point, it would be extremely advantageous in terms of handling and roll mixing work.

In the method (2), a method is known in which a bath solution of Co-n-B A CN is added to acetone, which is a poor solvent, and the mixture is reprecipitated and recovered as a powder. ()' to 1ori
La and M, lla+4iwara, J.
Anpl, Polym.

Sci., 273329 (1982)) Con-13ACN can be recovered by this method by concentrating the Co-low BACN solution obtained in the reaction in advance, since con-BACN dissolves in ascent to some extent. Subsequently, it is added to cold acetone (θ~-10'C) and reprecipitated, which has the disadvantage of requiring complicated operations. Furthermore, the recovery rate of Con-B A CN is also low.

The present inventors used a reprecipitation method using a poor solvent to recover Con-BACN as a powder, and were able to convert Con-BAC with a simple operation.
As a result of extensive searches for poor solvents to increase the recovery rate of H, we found that when using a saturated aliphatic monohydric alcohol with 3 to 5 carbon atoms, Co could be easily recovered with a high recovery rate.
It was discovered that n -B A CN could be taken up as a powder, and the present invention was completed. In other words, the present invention is based on the bromination, condensation, and hydrogenation reaction of acenaphthene (1). 4-17+'li is the precipitation of Con,...-13AcN as a powder by adding a solution of -BACN to a saturated aliphatic alcohol having 3 to 5 carbon atoms. C
The on-HACN separation and recovery method is provided as part of the process. .

Con-B ACN obtained in the manufacturing process referred to in the present invention
The organic solvent of the solution refers to a good solvent that dissolves Con-138CN, and is a halogenated hydrocarbon or aromatic solvent that is inactive in the dehydrobromation reaction. r & hydrocarbons are selected.

Examples include carbon tetrachloride, chloroform, methylene chloride, ethylene dichloride, ethylene dibromide, chlorobenzene, benzene, toluene, xylene, and ethylbenzene. Further, the concentration of the Con-BACN solution is not particularly limited, but 5 to 70% by weight is usually used.

The saturated aliphatic partial alcohols having 3 to 5 carbon atoms used in the method of the present invention include 1-propanol, 2-propanol,
-propanol, 1-butanol, 2-methyl-1-propanol, 2-methyl-2-propanol, 1-pentanol, 2-pentanol, 3-pentanol, 2-
Examples include methyl-only phthanol, 3-methyl-1-butanol, 2-methyl-2-butanol, 3-methyl-2-butanol, 2,2-dimethyl-1-propanol, etc., but reprecipitation Practically preferred are 1-propanol, 2-propanol, 1-butanol, 2-butanol, and U2-methyl-2-probanol, which are easy to dry and are industrially available.

In alcohols with carbon numbers of 2 or less, the dispersibility of Con-13ACN is poor (Con-BACN cannot be precipitated as a solid, and in the case of alcohols with carbon numbers of 6 or more, the solubility of Con-13ACN becomes worse, Con
-13A There is a drawback that the recovery rate of CN is low. Dimensions 2
In the case of polyhydric alcohols with higher valences or higher, the boiling point is generally high, making it difficult to dry the resulting powder.

The amount of these saturated oloaliphatic alcohols to be used is usually 1 to 20 times the volume of the Coll-13A Cf'l solution to be added, preferably 2 to 10 times the volume.

If the amount of alcohol is less than the same amount as Con-D A CN solution (Yo, Coo-'J3A, CN has the drawback of low recovery rate, but if it is more than 20 times the value, there is no problem with reprecipitation itself. However, this is not desirable because it is not economical.

Co11. - Reprecipitation of BACN is carried out by Con - BACN
This is carried out by adding the CN solution into the alcohol, preferably with stirring at that time. In addition, with normal stirring, etc., Con-BACN may partially solidify and it may be necessary to stir the crystals after drying. is desirable.

The term "agitation with shearing force" as used herein refers to, for example, agitation with shearing force such as forced stirring using a two-screw screen machine or a homomixer, which combines the good strength of Con-BACN with a poor solvent. Since it is possible to promote dispersed precipitation by stirring and to bring a good solvent into dispersion contact with a poor solvent, efficient precipitation can be achieved.

In other words, in the case of a normal reactor with one stirring mechanism, dispersion is inefficient and crystal precipitation is slow, but if two stirrs are used and the dispersion is properly controlled, the contact surface between the good solvent and the poor solvent can be improved. is expanded, the good solvent remaining in Con-BACN is extracted in a much shorter time than simply mixing and contacting, promoting the precipitation of the target product, and converting Con-BAC into
Efficient precipitation of N becomes possible. The crystals obtained are
Since it is obtained as a fine powder, crushing after drying is not necessary.

The temperature at which the Con-BACN solution is added to these alcohols should be below the melting point of Con and -BACN, but it is usually sufficient to add the Con-BACN solution to these alcohols.

The precipitated C on -B A CN powder can be separated by a conventional method.

For example, it can be separated by centrifugation at 81F, suction filtration, spray drying, etc.

As is clear from the above description, by implementing the method of the present invention, Con-B obtained from the manufacturing process
Easy operation from ACN solution Con-13A
It is extremely useful to use CN as a powder! 1 yield in minutes 1+1
Since it is possible to i+, Con, -HA CN
An economical manufacturing method has become possible.

Moreover, C o n -B A CN obtained by the present invention
is a fine powder and is made into a resin.
Since it is obtained as a compound with a higher melting point than CN, it is easy to handle and has excellent roll workability when mixed with resin.

The present invention will be explained in more detail with reference to examples below, but the present invention is not limited to these examples. 1. Example t 308 g of acenaphthene and 249 g of ferric chloride are added to 2.81 g of carbon tetrachloride. , and kept at 30°C. A solution of 1.9 bromine + <W 141 carbon 0.51 was added dropwise to this solution over 5 hours. After the dropwise addition, the temperature was raised to 55°C and the reaction continued until the color of bromine disappeared. After removing the insoluble matter in the reaction mixture by filtration and thoroughly washing the reaction solution with water, a solution prepared by dissolving 144I of potassium hydroxide in 0.61% of methanol was added dropwise over 1 hour while heating under reflux, and the reaction was allowed to proceed for another 1 hour. . After cooling the reaction solution, the potassium bromide salt was removed by filtration, methanol was distilled off, and the mixture was washed with water three times to obtain Con-B A CN.
620! A carbon tetrachloride plate of 3.61% was obtained. As a result of the analysis, the obtained C on -B A CN had a bromine content of 67% and a condensation rate determined by gel permeation chromatography. The degree is 35% below dimer, 42% dimer
%, and 23% of 4-8 folds.

This Con-B A CINN carbon tetrachloride solution,
0.451 containing 77.5 g'3 of Con-BACN was used for the next reprecipitation.

While vigorously stirring i-Propertool 1.8) with a Lab Disperser (manufactured by Mitamura Riken Co., Ltd.), add 1 part of the carbon tetrachloride solution to the room.
It was added dropwise in 20 minutes. Precipitation of fine powder occurred simultaneously with the dropping. After dropping, stir for another 20 minutes until the powder has completely precipitated, then dry at 75°C to obtain reddish brown powder CO11-i'3 with a melting point of 125-145°C.
A CN 70.51e was obtained.

CON -BA CN carbon tetrainide g'tL to Co
The recovery rate of 〇H to n-13 corresponds to 91%.

Example 2 1-Proper tool 1.86 was put into the middle of vigorous stirring with 'I', K, Homomixer (Specially, Chichi) manufactured by Nijika Kogyo Co., Ltd. Example 1 Nod! ! 'In Con-13A
A carbon tetrahydride solution containing 77.59 cN (0.451 g) was added dropwise at room temperature over 30 minutes. Precipitation of fine powder occurred simultaneously with the dropping. After dropping and stirring continuously for 20 minutes, it was separated from the oven and dried to give a reddish brown powdered Con with a melting point of 124-146°C.
-BACN 6'8.31 was obtained.

Con-f3AC from Con-BACN carbon tetrachloride solution
The N recovery rate corresponds to 88.1%.

Example 3 Into 1.81 ml of tart-butanol was gently stirred in a Lab Disno dispenser, C prepared in Example 1 was added.
o, n-13A A 0.451-liter carbon bath solution containing 77.5 g of CN was enriched with carbon at room temperature for 20 minutes.

Precipitation of fine powder occurred simultaneously with the dropping. After dropping, return for 20 minutes (after continuing to stir, separate from the oven and dry - C point 124 ~ 1)
70.1 g of reddish brown powdered Con-BACN at 45°C was obtained.

From Coo-BACN four whispering carbon melting glass (,' on
- The recovery rate of BACN corresponds to 90.5%.

Example 4゜77 g of acenaphthene and 6 g of ferric chloride were mixed with carbon tetrachloride'=K
700 ynl and kept at 30°C. A solution containing 475 g of bromine and 125 g of carbon tetrachloride was added dropwise to this solution over 4 hours. After the dropwise addition, the temperature was raised to 55°C, and the reaction was continued until the color of bromine disappeared. Insoluble matters in the reaction solution were removed by filtration, the reaction solution was thoroughly washed with water, concentrated to dryness, the residue was dissolved in 550 g of benzene, and 36.9 g of potassium hydroxide was dissolved in 150 g of methanol under heating under reflux. The solution was added dropwise over 1 hour and reacted for another 1 hour. 1. After cooling the reaction solution,
The potassium bromide salt was filtered off, the methanol was distilled off, and the mixture was washed with water three times to obtain 6001 df of a benzene solution containing 152 g of Con-BACN. The obtained C0n-BA
CN has a bromine content of 68% and a degree of condensation measured by gel permeation chromatography of 36% or less, 3
The amount was 43% as mer and 219 as 4- to octamer.

This benzene solution was added dropwise over 30 minutes at room temperature into 2.4 liters of n-amyl alcohol which was being slowly stirred with an ordinary blade. After dropping, precipitation of powder occurred.

After stirring for 30 minutes after dropping, the powder was separated from the oven and dried. Although some solidified Con-BACN was contained in the powder, it could be easily crushed with a household mixer. Yellow-brown powder Con-BACN with a melting point of 126-146°C
130.7Ii was obtained.

Con-BACN from benzene solution of Con-BACN
The recovery rate corresponds to 86%.

Comparative Example 0.451 of the carbon tetrachloride solution containing 77.59 of Con-HACN prepared in Example 1 was added to cold acetone (0 to -
It was added dropwise into the 10°c) sl while stirring in the same manner as in Example 1. After dropping, the precipitated powder was separated and dried to give Con-BACN in the form of a yellowish brown powder with a melting point of 126-146°C.
55, OI/ was obtained. C.

n -B A CN Con-BAC from carbon tetrachloride solution
The N recovery rate corresponds to 71%.

Patent Applicant Toyo Soda Kogyo Co., Ltd. Procedural Amendment 1 May 11, 1980 q,! Mr. Kazuo Wakasugi, Director General of the License Agency 1 Indication of the case 1982 Patent Application No. 201119 2 Name of the invention Method for separation and recovery of brominated acenaphthylene condensate 3i11j
Relationship with the person making the correction Patent applicant telephone number (58513311 Date of the 4th supplementary iE order Vol. 11, 7.' Contents of the persimmon 7th amendment of the "Detailed description of the invention" in the specification subject to the 6th amendment ( 1) The specification officer shall be amended as follows.

Page line Before correction After correction 3. 17. 10 or less refers to 10 or less.

Preferable.

1115 Dimer or less Monotope 1115 trimer dimer 11164-octamer 3-octamer 14 82mer or less Uniclawed body 14 86-mer 2-view body 14 84-octamer 3-8 claw body

Claims (1)

[Claims] In a method for separating and recovering a brominated acenaphthylene condensate produced by bromination, condensation and dehydrobromination of acenaphthene, a solution of the obtained brominated acenaphthylene condensate is converted into a saturated aliphatic compound with a carbon number of 3 to 5''! A method for separating and recovering a brominated acenaphthylene condensate by adding it to a monohydric alcohol.