JPS5834819A - Deactivation of polyoxymethylene copolymer - Google Patents

Abstract

PURPOSE:To deactivate residual catalyst effectively and thereby imporve stabilization yields, by grinding a polyoxymethylene copolymer prepared by cationic polymerization to a powder,diameter <=20 mesh, and then contacting the powder with a basic neutralizing agent. CONSTITUTION:Trioxane and a cyclic ether (e.g., ethylene oxide) or a cyclic formal (e.g., diethylene glycol formal) are cationically copolymerized at about 60-120 deg.C in the presence of about 10<-4>-1mol%, based on trioxane, catalyst (e.g., boron fluoride dibutyl etherate). Then the residual catalyst in the produced polyoxymethylene copolymer is deactivated by grinding the copolymer to a powder, diameter <=20 mesh, mixing and reacting this powder at above 50 deg.C with a solution of a basic neutralizing agent (e.g., triethylamine, calcium hydroxide) (the mol ratio of the neutralizing agent to the catalyst is about 1-10<-3>).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is based on a heavy-duty platform for producing highly crystalline polyoxymethylene copolymer industrially at low cost.
This relates to a method for inactivating.

-1iK, polio I? Cumeterene copolymer is usually produced by copolymerization of trioxane and other comonomers such as Il-like ethers or acetals in the presence of boron fluoride and its compounds in the electrophilic catalyst 411. Later, the srs containing E1m in the polymer is inactivated at 10"lsK in a basic environment, dried, and then subjected to stabilization step 1 to obtain a product. In the deactivation step, neutralization is insufficient and ．If 1IIE section f remains in the copolymer, the thermal stability of the copolymer becomes vague.
The yield in the stabilization process excluding the terminal unstable part after bundling (
The stabilization yield (hereinafter referred to as "stabilized yield") decreases, the manufacturing cost increases, and the quality of the final product also decreases. In order to produce high quality polymers at low cost, the deactivation process is extremely heavy.

Until now, there has been very little study on how to effectively perform deactivation.
41 Kin 1635-3542 covers the deactivation jl@ and mentions washing the neutralizer with an organic substance, but it is not possible to effectively inactivate the neutralizer as described in this IA@. 'C' does not mention the crushing of polymers for the purpose of pulverization.

脣子＠4g-8342 talks about the process of pulverizing the polymer during deactivation, but the average ml of the pulverizer is only 5 to 20 cm, which is only a large diameter one. Furthermore, in 臀＠55-164212, a neutralizing agent maple mixer is used to reduce the particle size of the polymer so that it passes through a 10 mesh sieve when exiting from the mixer outlet. However, this is for the sake of suitable handling during the subsequent stabilization process, and in fact, with an overlift degree of 10 meters, deactivation cannot be effectively performed. In this method, deactivation is not carried out sufficiently, and the thermal stability of the copolymer after deactivation is low (therefore, the stabilization yield is also low at 90-95 mm, making it difficult to obtain a product with excellent thermal stability). @cal cannot be advanced.

The present inventors have conducted intensive studies on the effect of crushing copolymers on deactivation, and found that the particles of copolymers 1!141=2
If 0 mesh or less is pulverized and deactivated, a copolymer with excellent thermal stability can be obtained, and the stabilization yield can be over 98% in 11 stabilization steps! Raise it with Hosomi IIc! l! Accordingly, the present invention is made.

Here, thermal stability is the percentage of the weight of the polymer after heating the dry polymer at 222° C. for 50 minutes under vacuum to the weight of the polymer before heating (41c), hereinafter referred to as B. The value of Rma is in good agreement with the stabilized yield.

The present invention provides trioxane and a cyclic ether or a cyclic hol! - Contact with a basic neutralizing agent such as a polyoxymethylene copolymer obtained by cationic copolymerization with
This is a deactivation method that is characterized by contacting with particles with a particle size of 20 mesh or less when inactivating the compound, but the trioxane used in the beginning is a cyclic trimer of formaldehyde. For example, ethylene glycol, the high boiling point compound of trioxepane firefly, water, formic acid, methanol,
Meral and Trio S? Lifting platform IIc containing extremely small amounts of polymerized carbonate, etc., is used.
is used as a raw material after being made into cloth in advance.

As the cyclic ether, ethylene oxide, dioxolane, etc. are used, and ethylene oxide is usually used.

Further, as a cyclic formal, diethylene glycol formal, phthanediol formal, hibentanediol formal, etc. are used, and the amount of bill-like ether or formal trioxine is 5r'J & 10.
It is 1 to 30 moles whisper.

These raw materials are fed to a polymerization machine together with a catalyst or a molecular weight regulator and polymerized at an appropriate temperature. As the catalyst, complex compounds of fluoride ist* with ethers, phenol esters, dialkyl sulfides, etc. are used, and boron fluoride dibutyl etherate and boron fluoride diether etherate are suitable. It is usually used at a concentration of 1% to 1% by mole.

It is preferably used at a concentration of 10-1 to 101 moles.

The department's supply of 1.1 m is made with ** diluted with ** such as cyclohexane, benzene, toluene, etc. At the same time, the molecular weight regulator is also supplied with sufficient adjustment in advance in this sii. Methylal, methyl orungate, etc. are used as molecular weight regulators, and the molecular weight is usually controlled within a molar ratio of I F'-3X 10-'' to trioxane. Cabinet, j
It is carried out at a temperature of 60 to 120C.

The preferred type of polymerization employed industrially is concrete polymerization. Since bulk polymerization does not substantially use a solvent, the recovery cost in the #1 section is low (and therefore economical. As a form of 1-polymerization, Rho=yJl (Special Publication No. 48-83422, or a kneader,
For example, a two-shaft self-cleaning kneading machine (41-Introduction 5)
6-38312) is known.

The copolymer obtained by polymerization is usually brought into contact with a basic neutralizing agent in order to neutralize the residual oxidants in the copolymer.

As the basic neutralizing agent, triethylamine, tributylamine, calcium hydroxide, triphenylphosphine, ammonia, alkali carbonate, hyaminoamide, etc. are usually used. Preferably triethylamine, tributylamine and calcium hydroxide are used. This basic neutralizing agent can be mixed with water, cyclohexane, benzene,
Xiaomiru O can also be used by dissolving it in an organic solvent such as toluene.
In this case, preferred solvents include water at °C for triethylamine and calcium hydroxide, and cyclohexane, toluene, benzene, etc. for tributylamine. The amount of neutralizing agent used is in each case 1
[Also, Kaji with a molar ratio of 1-10S to mol.]
used in In terms of weight, it is desirable to have a value of 10 times or more, and more preferably a value of 10” or more is 1ltL.

In order to carry out deactivation very effectively, after polymerization, co-1
must be crushed before or during contact with the compound neutralizing agent. In this case, it has been found that when the particle size is set to 20 meshes or less, the deactivation progresses dramatically and the thermal stability of the obtained copolymer becomes extremely high. When the particle size of the copolymer is reduced to a small particle size of 20 mesh or less, the Rv of the polymer after deactivation is increased to 98% or more, and as a result, the subsequent stabilization yield is also 98% or more, resulting in stable It has been found that the loss of polymerized products during chemical reaction is also reduced, which is a favorable result from an economic point of view. It is easily assumed that the product after inactivation is excellent in quality such as thermal stability and color.

In a large 11-valent copolymer with 20 meshes or more, at industrially practical temperatures, 8M does not reach 98%, but is at most 96%, which is -1! i! Unstabilized Yield Yield %S0 It should be noted that it is sufficient that the particle size is substantially 20 mesh or less, and a small amount of particle size of 20 mesh or more that does not affect the overall thermal stability is used. Even if it contains these things, it does not become a porcelain pottery.

It is presumed that as the particle size decreases, the chances of II- interaction between the catalyst remaining in the copolymer and the neutralizing agent increases, and thus deactivation proceeds effectively.

In addition, the time required for inactivation is 111j, and the particle size becomes smaller.
It only takes a short time, and contact under stirring for about 30 minutes for a copolymer with a size of 20 to 40 meshes and about 5 minutes for a copolymer with a size of 100 meshes is sufficient.

Regarding the degree of negativity during deactivation, higher temperatures promote deactivation more effectively, and temperatures of 50° C. or higher are particularly effective.

The seventh reason is presumed to be the increased chance of contact between the catalyst remaining in the copolymer and the neutralizing agent, as well as the effect of pulverization.

However, even at high silver levels, it is public expense to crush the copolymer to a diameter of 20 meshes or less and inactivate it by 1.

For example, even when heated at 140° C., a high Rv of 98% or more cannot be achieved with large particles of 20 mesh or more.

Generally, the copolymerized product copolymerized by a polymerization machine is sent to a tank containing a neutralizing agent solution. Flow nitrogen all the way to the tank and seal it.

The tank is equipped with a rotary stirrer and a slurry circulation pump in order to increase the efficiency of contact between the copolymer and the neutralizing agent. A heat exchanger is also installed to regulate the deactivation temperature.

Even with the above method, the copolymer 111! If the amount does not fall below 20 meshes, a pulverizer is used. As a crusher, a crushing type, crushing type, or cutting type crushing device with a 1-tatami passage, such as a jar f pointed shaft type or an impact type four-turn mill, is used, but during one polymerization, for example, a two-shaft self-cleaning machine is used.
It is also possible to crush the material by increasing the rotation speed or reducing the clearance in the case of an Ih kneading machine. After the deactivation process, the copolymer is separated from the neutralizing agent by centrifugation, dried, and then subjected to a stabilization process to become a product.

The effects obtained by the above method are: 1. The thermal stability of the copolymer after deactivation is low.

2. High stabilization yield and low manufacturing cost.

3. Excellent quality of final product. (thermal stability, color), etc., and the significance of using this deactivation method industrially is great.

The details will be explained below based on examples.

Example 1 Boron trifluoride dibutyl etherate was decomposed into trioxane with lXl0' mole of cyclohexane Kflr as a catalyst, and from a mixture with trimexane containing 4 moles of ethylene oxide to trioxane, a biaxial self-produced A copolymer of trioxane and ethylene oxide is produced by cleaning type kneading. However, as a molecular weight regulator, metheral was added in advance in an amount of 10 times the part amount in molar ratio. The copolymer is brought into contact with 0.51 volume of triethylamine water bath solution in a tank and stirred with a stirrer at 62C for about 90 minutes. Copolymer (JJ O, i 9k ) The ratio of ethylamine to water NICK is about 20 by weight. After stirring, at 4 o'clock, the triethylamine water 5at of the copolymer which had become sticky was drawn out from the bottom of the tank, and the product was ground using a line mixer (41 Jukika Kogyo 11T) using a pipeline homomixer. The resulting slurry was centrifuged.

The co-1 compound is separated from triethylamine water S solution, and water fl
After cooling, it was heated and dried at 126° C. for about 3 hours under nitrogen flow. The obtained t*-treated polymer was sieved through meshes of various sizes and scooped out in an amount of $1 ml. Rv's glue setting iron is lA! As described in the book, IE dried polymers are true! Heat at 222° C. for 50 minutes to determine polymerization and determine the weight relative to the weight before heating. Including the case where a line mixer was not used, 31 parts of water was added to the polymerized product, and 31 parts of triethylamine was added to the polymerized product. Added .025% by weight, 200℃
The stabilized yield was defined as the weight percent of the polymer obtained from the extruder outlet with respect to the polymer fed to the 0 extrusion ridge to take out the elastic component from the vent section. The relationship between particle size and stabilization yield is shown in FIGS. 1 and 2. The average Rv of the polymer after drying without using a line mixer and when using a line mixer was 945% and 9k2%, respectively, and the average stabilization yield was 94.1% and 97.5%, respectively.

After stabilizing the polymer with a particle size of 6 (*IK indicates the formation observed visually with the naked eye).

In Figures 1aii to 4, the grain size lii is taken as the axis of the figure, but the aS scale indicates the grain size range, and for example, 2G-
12 means that the particle size is 20 mesh or more and 12 mesh or less.

Example 2 - The compound obtained by the method described in Example f11 was brought into contact with 0.5 wt % ethylamine aqueous solution II in a tank at a temperature of 40°C and 50°C and 180°C for about 90 minutes. , and inactivated by stirring with a stirrer. The ratio of compound 1 to the triethylamine aqueous solution is about 20 parts by weight. Quinmikisu was used in the same area as described in Example 1. After centrifugation and AM, ecR samples were collected for each grain.

Also, it was brought into contact with a copolymerized O, S weight s triethylamine water S*.

20 weight centrifuges, placed in a stainless steel micro cylinder, m
#5 Condition: 100℃, 120Kl:, 6% of 140C
For 90 minutes inside, I was gently moxibusted to a figure 8 and 11 shape, and it was inactivated. After deactivation, the copolymer was separated from triethylamine water St by mouth filtration, and after washing with water, it was washed with water. ! In the dryer, 120℃
The method of drying it for 511 minutes, sifting it to 1 particle size j41, and scooping out kv was the same as the method described in Mlil. The results are shown in Figure j13.

111fl! i3゜trifluoride m complex diethyl etherate to trioxane to sea CO, 7X 10-4 seven lula, cyclo to dt t #! 2 from a mixture with trioxane in a ratio of 4 molar to ethylene oxide trioxane.
@Self-cleaning 41 kl of copolymerization of tris-xane and ethylene oxide was produced in the m-kneading kiln. However, the molar ratio of metheral is 7 in advance as a molecular weight -jI agent.
Weight -1.

Pour the copolymer into 1rui (3 weights of toluene 111EK to tributylamine pre-prepared in quina) and 11 to 20 weights of toluene to 11[tc].
Is, 30, 60, 90, 120 minutes of contact and stirring, the negative temperature after stirring is 62°C.

That is, the copolymer was passed through the mouth, washed with water, and vacuumed with i1E bran.
C. After drying for 5 hours, 11 ml of the product was separated using a sieve. The Rv of each particle size was kept constant. Relationship between yB diameter and Rv in % contact time! ! 44.

The method for determining Rv is the same as that for real #A.

Practical Example 4 The copolymer obtained in the same manner as described in Practical Fill was crushed by a crusher (Jiyo Crusher), and after being crushed, it was brought into contact with 0.5 weight bone tributylamine water in a tank. The mixture was stirred for about 90 minutes at 62°C using a stirrer. (% by weight of O and S in the compound) 111 to IJ etelamine water St is about 20% by weight. The obtained slurry was centrifuged, and the copolymerized product was separated with 1 cup of triethylamine water, washed with water, and then 126
It was heated and dried at ℃ for about 3 hours. The Rv of the obtained polymer was made constant by the method used to block the actual Jlfill.

The dry weight of the IIL copolymer was 99.0%, and the weight of the IIL dry copolymer when not used in the drying process was 94.8%. In addition, the compound after drying was stabilized using the same method as in Example 1, but the stabilization * was 98
．． It was 3%.

The copolymer obtained in the same manner as described in Example 1i115゜Example J1if13 was brought into contact with 0.1 kg of calcium hydroxide water ini and stirred with a stirrer at 62C for 90 minutes. A line mixer (registered 111m Kakogyo@
The slurry was ground using a pipeline homomixer. After step 7, the compound was separated with calcium hydroxide water 1iii in a centrifuge, washed with water, and dried at 126° C. for about 3 hours under iii1 cumulative flow.

[The Rv of the dried copolymer was fixed in the same way as was carried out in Example 1. Rv was 9&5%.

[Brief explanation of the drawing]

FIG. 1 shows the relationship between Rv, stabilization yield, and a diameter when no line mixer is used. #! Figure 2 shows the relationship between By, stabilized yield, and particle size when a line mixer is used. Figure 3 shows the influence of inactivation negativity on the lIl relationship between Rv and particle size. 4wA indicates the effect of contact time with the neutralizing agent on the relationship between Rv and particle size. Supporting Applicant: Asahi Kasei Kogyo Co., Ltd. Figure 1 Can Nasori ← Chih Street i (Metsu, Shu) Figure 2 Waste? Ju (,%tsuki) Fig. 3 #L spitting aJ (metshu) Fig. 4 Rice [Sushi Gua 4 (metshu) Procedural amendment (voluntary) November 2, 1980 Commissioner of the Japan Patent Office Shima 1) Haruki Tono 1, Incident Display 1981 Patent Application No. 1320? T
No. 2 Name of the invention Method for deactivating polyoxymethylene copolymer a Relationship with the case of the person making the amendment Patent applicant 1-2-6-Tun Dojimahama, Kita-ku, Osaka-shi, Osaka Prefecture Invention of the specification subject to the amendment Contents of the amendment in the "Detailed explanation of the invention" column The entire "Detailed explanation of the invention" column in the specification will be amended as follows. that's all

Claims (1)

[Claims] A polyoxymethylene copolymer obtained by cationic copolymerization of (11-9-11?nan and a cyclic ether or a cyclic formal) is prepared using a basic neutralizing agent and an increased degree of a! A deactivation method in which 41 molds are contacted with a particle size of 20 mesh or less when contacting and deactivating the parts. (2) Polyoxymethylene copolymer and basic neutralizing agent are
11. Keep the temperature at 50℃ or higher when cooking.41
11 Claim II Deactivation method according to item 1 (3) Integral use of boron trifluoride as a catalyst for cationic copolymerization Deactivation method (4) Deactivation described in Section 3 of IK Encyclopedia of Patent M, characterized in that the boron trifluoride complex is boron trifluoride dipterether A- or diethyl ether. Method (5) Deactivation method (6) Trioxane described in item 1 of the patent-claimed claim, characterized in that one of tributylamine, tributylamine, or calcium hydroxide is used as the basic neutralizing agent. A polyoxymethylene copolymer obtained by cationic copolymerization of and a cyclic ether or @-form formal is contacted with water or an elevated ILIL such as @II in a basic solution decomposed with m
A deactivation method characterized in that when inactivating at, contact is carried out with a particle size of 20 meshes or less