JPS59159812A - Continuous polymerization of trioxane - Google Patents

Abstract

PURPOSE:To obtain continuously a high-quality polyacetal, by uniformly mixing, trioxane with a Lewis acid or mixing these with a cyclic ether under heating and feeding them maintained in a liquid phase to a polymerizer. CONSTITUTION:In the continuous polymerization for obtaining polyacetal by the homopolymerization of trioxane in the presence of a Lewis acid as a catalyst or the copolymerization of trioxane with a cyclic ether in the presence of the catalyst; the trioxane is mixed uniformly with the Lewis acid, or these are mixed uniformly with a cyclic ether at 64-140 deg.C for 10-300sec, and the mixture maintained in a liquid phase is fed to a polymerizer. Preferably an agitator-mixer, static mixer, or double-shaft reactor is used. When an agitator-mixer is used, the distribution of a dwell time tends to be widened, so that it is preferred to use an agitator-mixer adapted to provide a sharp distribution of the dwell time.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a continuous polymerization method for trioxane, and further to a continuous polymerization method in which trioxane and a polymerization catalyst are uniformly mixed together using a Th'P system and then supplied to one polymerization reactor.

It is well known that substantially anhydrous trioxane is subjected to violet polymerization in the presence of a polymerization machine or copolymerized with a compound of ethylene oxide to obtain polyoxymethylene with a pot molecular weight.

1M is also known, in which homotogane and copolymerization of shredded tatrioxane are carried out continuously in 16 bales of polymerization fabric in a bulk state.

For example, in Japanese Patent Publication No. 44-5234, Connie
A uniaxial polymerizer known under the name Ko-Kneador is used. In addition, the special public service
No. 9 and Japanese Unexamined Patent Publication No. 51-84890 propose the use of biaxial polymerization vd. In these methods, trioxane and direct polymerization are insufficiently mixed. Due to the localization of the heavy financial medium, the local polymerization force of trioxane is suppressed, resulting in locally extremely high temperatures, resulting in severe deterioration of the pentapolymer.

In order to overcome all of these deficiencies, in % Publication No. 57-44690, two or more polymerization machines are connected in a row,
Polymerization of = 1 (from the outlet of the tube, conversion rate 40 to 60 mol φ
A method has been proposed in which the polymerization product of is used as a ψJ form.

In this method, trioxane and xK in the first polymerization machine are also
Mixing of the polymerization catalyst is insufficient.

Trioxane generates heat during polymerization. If this heat of polymerization cannot be properly removed, the polymerization product will be degraded3).In addition, in this method, Hatake 1 is combined and the polymerization product is already powdered. There is. 5. It is extremely difficult to remove polymerization 2 from powder. For this reason, this method requires a large heat removal area per certain treatment A- (tunhedong) of trioxane9, and at the same time, this method requires a large amount of internal heat generation and heat (friction fever) 1
Not only polymerization heat! +'j'l We must also take away the frictional heat. This also means that the first polymerization q;i! To! This is one of the reasons why ti becomes larger and more flexible.

In U.S. Pat. No. 54-161695:! :, 1
: , J. Polymerization with 3-state ether; 1i1 (polymerization through a gold nozzle with a medium), and a method in which the tip of the nozzle is washed away with a stream of trioxane is disclosed.

This method is certainly an improvement over the conventional method in mixing trioxane and polymerization. This is a practical effect, and we have no choice but to rely on the conventional method of determining the heat of polymerization.

In order to produce high quality polyacetal, the present inventors
Trioxane and nail syncytosis medium are mixed uniformly, and at the same time, l'1. caused by iK combination. It is necessary to efficiently remove the initial polymerization heat.
ljj was reached and the present invention was completely completed.

That is, the present invention involves a series of trioxane polymerization reactions in which trioxane and a Lewis acid, or trioxane, L-shaped ether, and a Lewis acid are uniformly mixed at a certain rate and time range. After that, the reaction mixture is completely polymerized while leaving the liquid phase state (this is a continuous polymerization method of trioxane supplied to the formula).

Using the method of the present invention, ζV (therefore, the polymerization of trioxane and the Lewis polymer, which is an insect medium, is carried out uniformly in the 1' sections, and the initial polymerization heat is is efficiently removed 3. The following details will be explained in detail below.

In the present invention, trioxane or trioxane, a cylindrical ether (hereinafter abbreviated as "monomer", 111) and Lewis Co., at a certain temperature and time; t, +] , :j; giant 1
20 minutes outside the building, mixed with 1'C).

In Un#3 Ming, the retention 1 Samurai: it'1 distribution is sharp, Imiai, 餞, that is, the proboscis (plug) flow in the mixed '3 () q part (4's c2 (this)) is close to the piston (plug) flow, In addition, it is preferable to use a 1-combination machine that is close to 1-mokuri-minori and can create a dead space (ultra-retention space).

In the present invention, the monomer and the Lewis acid are mixed together. It is necessary to feed 〃′ to the polymerization machine while maintaining the surface phase state. If there is a residence time distribution in the mixture, the fraction with long ILl during residence is likely to solidify and powder.1. Once solidified or powdered, it becomes difficult to remove the initial polymerization heat. Furthermore, when solidified or powdered, radical opening of the mixture often occurs. Therefore unexploded r14
In this case, this formation and powdering must be avoided. .

On the other hand, the fraction with a short residence time (the release of polymerization heat during the sword stage is insufficient, and the 1-tatami heat produced in the polymerization 4'D+ will be generated, and the core is removed inside the polymerization-like interior) is Since it becomes solidified and powdered, it is quite difficult to remove the heat of synthesis from the −7 mixture. It can also be a cause of poor performance. In addition, this fraction does not necessarily mean that the +JL 'rl of the monomer, Lewis 1, and evening is equal to H(((There are cases where it is not advanced: 0. Therefore, in the + invention, this 7(tjjl; stand'j# The production of short fractions of fJ] must also be avoided.

From this point of view, in Komei, the stirring mixer, static mixer, and 2':'a1 reactor are recommended as mixers.

Here, the term "primary agitation mixing" refers to mixing having a stirring means such as a uniaxial '+', 'a+ pourer, a loco, an impeller, or the like.

B; Stirring mixed bales tend to have a broad distribution during residence, and in the present invention, a method to sharpen the residence time distribution is adopted. Is there a Ph1-1 child? is desirable.

For example -4:, 110-ter 1'3"!, "rU mixture,
-・For 3 and 2, the rotor and casing are fitted with a clearance plate, and a spiral @ is drilled in the Kuonong to make the flow of the contents as close as possible to the piston flow. Alternatively, it is necessary to devise a way to make the entire piston flow through the rotation of this pin by attaching the entire rotor to the -7,5-spiral-shaped piston.

What is static mixer?
has a baffle board inside; the flow of two shellfish flows into this baffle board (
i5 The mixture is created by conflict + j
Does l also match? The long body - then the rule, ;,! I, t, 5 minutes, and so on.

The two-axis mixed cannon is two cooperative I!
The mixing means such as a screw, paddle, disk, or pin is directly connected to this ``hair erection 1:''.

The two drive shafts rotate 3 degrees in the same direction or in different directions, and the screws, paddles, etc. attached to the other shaft rotate with a certain clearance between the screws, paddles, etc. and the casing (barrel) to achieve mixing. will be accomplished.

In a twin-shaft mixer, when the screw, paddle, etc. are engaged with the screw, paddle, etc. of the mating shaft, self-cleaning property 1 flood is exerted on the load. Cleaning equipment refers to screws, paddles, etc. in Table 1 ■i:,・υ゛A is 14゜↓
It signifies power to 1+, which is renewed and replaced by a new substance.

This self-cleaning performance of the present invention is the first of its kind in electric type.

Items on the mixer wall, screw surface, etc. have been updated to make them difficult to flow. This increases residence time, and in the present invention, reaction mixing (necessarily solidification and
Easy to powder. In the present invention, it is necessary to solidify and powderize the reaction mixture, and in that sense, self-cleaning is a major requirement.

In the mixing of the present invention, the initial polymerization heat is removed while mixing is achieved. The initial heat of synthesis is efficiently removed when the reaction mixture remains in a liquid phase. The reaction mixture became a 1d body and powdered and became an in-phase state 4-
In one case, the removal of the heat of reaction becomes markedly difficult.

In order to remove the heat of initial polymerization, the mixer of the present invention is usually equipped with a jacket. Initial polymerization is removed by passing water through the jacket. Two Li+ again! ](
The inside of the shaft is made hollow, and the water flowing through it also removes the hatsijidamagoro.

In the present invention, the monomer and the 2-catalyst have a molecular weight of 64 to 140
Mixing temperature: ℃ - Mixed at ambient temperature. During polymerization at temperatures below 64° C., solidification of trioxane occurs. If the mixed iA'a K exceeds 140° C., deterioration of the reaction mixture (hydride shift and increase in side reactions known as +i%) and significant vaporization of unreacted trioxane occur. Therefore, the mixing temperature must be strictly controlled within the range of 64 to 140'C1tjJ. 'Also, in the present invention, the monomer and the polymerization catalyst are mixed for a mixing time range of 10 to 300 seconds. Here, the mixing time of the present invention is a value defined by the following formula.

For polymerizations with mixer times of less than 10 seconds, removal of the initial polymerization heat is insufficient. As a result, the amount of heat generated within the polymerization machine increases,
The quality of the polymer decreases. If the mixing time exceeds 300 seconds, side reaction products will increase and a large volume of water will be required. jt
A joint opportunity is required. Furthermore, in this case, solidification of the reaction mixture occurs within the mixing chamber, and continuous polymerization often cannot be continued.

Therefore, in the present invention, the mixing time is strictly 10 to 30 minutes.
It is 8 times to set it in 0 seconds. .

In the present invention, the reaction mixture in the mixer is supplied to the polymerization machine while maintaining a liquid phase state.

In the present invention, a conventionally known trioxa/polymerization reaction) can be used as a polymerization machine. Furthermore, in the present invention, among these polymerization reaction methods, a twin-screw reactor is preferably used. The 2R extraction reactor here is Special Publication No. 47-629 Kotan 3. Japanese Patent Publication No. 51-84890, Japanese Patent Application Publication No. 56-
As disclosed in Publication No. 38312, etc.,
There are two drive shafts inside the reaction chamber, and a cross-connection means such as a screw, paddle, cylinder, bottle, etc. is directly connected to this one drive shaft. The two drive shafts rotate in the same direction or in the same direction. An example of such a two-wheel reactor is the KR
C Neegu (Kurimoto Chichikosho), Tex (Nihon Seishirosho)
, Tem (Toshiba Machine), ZSK (Unirna)
&Priderel), AP-conti (list)
etc.

Inside the polymerization machine, the polymerization reaction of the liquid phase reaction mixture coming out of the mixer further progresses, and a solidified/powdered polymer is obtained at the outlet of the Teiai Chino.

Since polymerization heat continues to be released inside the polymerization machine, it is necessary to remove the heat. However, in the present invention, since the initial polymerization heat can be removed in the mixer, the amount of heat removed from the polymerizer is small, and heat removal can be performed extremely easily.

Due to insufficient heat removal in the polymerization machine, the temperature of the solidified/powdered mass increases. As the product temperature rises, a polymer cleavage reaction called hydride shift occurs frequently, causing a decrease in the molecular weight of the polymer. This reaction also reduces the thermal stability of the polymer.

Hydride shift-()CH20CI(2-→-0CH3+HCOCH2
'- (- moistens the chain of oxymethylene groups.) In the present invention, the heat of polymerization can be efficiently removed, so hydride
A high-quality polyacetal with extremely little shift, a simple degree of integration, and high thermal stability can be obtained.

In the present invention, since the heat of polymerization can be efficiently removed, there is no need to use a large amount of polymerization solvent. In the present invention, the polymerization solvent contains not more than 30 M% of trioxane, more preferably 1
It is used in a quantity ratio of 51% or less.

Polymerization solvents that can be used in the present invention include aliphatic hydrocarbons such as pentane, hexane, heptane, and cyclohexane; aromatic hydrocarbons such as benzene, toluene, and xylene;
There are purple halogenated hydrocarbons such as methylene chloride and ethylene dichloride.

In the present invention, a Lewis acid is used as a polymerization catalyst for trioxane homopolymerization and copolymerization.

The first group of Lewis acids includes tin tetrachloride, tin tetrabromide, titanium tetrachloride, aluminum trichloride, zinc chloride, vanadium trichloride, phosphorous trifluoride, antimony trichloride, boron trifluoride, and trichloride. There are 7 Riedel-Crafts type compounds such as boron. Also, boron trifluoride diethyl nitele-1.
Also included in this group are boron trifluoride coordination compounds such as boron trifluoride dibutyl etherate, boron trifluoride dioxanate, and the like.

The second group of Lewis acids includes organic acids such as chloric acid, acetyl verchlorate, t-butyl verchlorate, and the like.

The third group of Lewis acids includes complex salt compounds such as triphenylmethyl hexafluorophosphate, allyldiazonium hexafluorophosphate, and triethyloxonium tetrafluoroborate.

In addition to these three groups, molybdenum oxide acetylacetonate and the like can also be used as Lewis acids.

Among these Lewis acids, free chill-kraft type compounds and complex salt compounds are preferred, and boron trifluoride and boron trifluoride coordination compounds are particularly preferably used.

Lewis acid is 1 x 10-5 to 1 mole of trioxane.
X 10'' moles are mixed in a mixer.

Since boron trifluoride and boron trifluoride coordination compounds have a high ability to initiate polymerization of trioxane, these compounds are mixed at a ratio of 1X10' to 5X10-' moles per mole of trioxane.

In the present invention, trioxane is homopolymerized or copolymerized with a cyclic ether.

A first group of cyclic ethers that can be used in the present invention are alkylene oxides such as ethylene oxide, propylene oxide, butylene oxide, cyclohexene oxide, styrene oxide, and the like.

The second group of cyclic ethers are cyclic formals such as ethylene glycol formal, diethylene glycol formal, triethylene glycol formal, 1.4-7'' tanediol formal, 1,6-hexanediol formal.

Among these cyclic ethers, ethylene oxide and ethylene glycol formal are preferably used.

The cyclic ether is 5 x 10 per mole of trioxane.
Mixed in a mixer in a proportion of "-'~6X10" moles.

Ethylene oxide and ethylene glycol formal, which are particularly preferably used as the cyclic ether, are mixed in a proportion of 2.times.10@-3 to 1.times.10" mol per mol of trioxane.

Further, in the present invention, a molecular weight regulator such as methylal can be used to control the molecular weight of polyacecool.

The homopolymerization or copolymerization of trioxane with a cyclic ether of the present invention is usually carried out at a temperature range of 30 to 150°C. Also, there is no limit on polymerization for 1 hour, but
1t('' is selected during polymerization for 40 seconds to 50 minutes.

Next, basic substances such as sodium hydroxide, ammonia, amines, and quaternary ammonium salts are added to the polymer coming out from the polymerization nucleus outlet, and the Lewis acid used as a 1i1'' catalyzer is neutralized and depleted. activated.

After neutralization and deactivation of the Lewis acid, the heptapolymer is heated with water, alcohol, etc., and the unstable portion of the polymer end t'y:i' is removed and stabilized.

Heat stabilizers, anti-branching agents, light stabilizers, and the like are added to the stabilized polymer for use in commercial applications.

By using the mixing method of the present invention which has been described in detail above, it has become possible to efficiently produce polyacecool of still higher quality. The following actual JJ1a so 11V? -Measurement values are based on the following measurement method.

Reduced viscosity: Polymer concentration 0.5 fr in p-chlorophenol/tetrachloroethylene (l:1 weight ratio) solution
/dll, measured at 60°C, scale β of molecule J1i
: Concentration of formate groups (HC-) in the polymer base. The higher β is, the more intense the hydride shift is occurring.

Rv * The residual rate of the polymer when the polymer was heated at 222°C under vacuum for 50 minutes id. The higher the Rv, the better the thermal stability of the polymer.

Example 1 (1) Uniform mixing (example using stirring mixed cherry) Trioxane, ethylene oxide, benzene, and tris-13 boron dibutyl etherate were instantaneously mixed in the following proportions.
An S-1 mixer (Sakura Seisakusho) was provided, and an instant mixing wipe with a low rotational speed of 1800 rpm was also installed.

Trioxane 15i (g/hr ethylene oxide 330 fl/hr benzene 1.
2 t/hr BF30Bu2 3.3 fr/hr The old mixer used here has a clearance between the rotor and the casing of 2.0 mm, and has a large number of disaster pins on the rotor. As usual, it is a mixer designed to transport the contents in a flow similar to that of a piston.

During uniform mixing, water was passed through the jacket of the instant mixer to remove heat in order to maintain the internal liquid temperature at 85°C.

Further, the mixing time was 46 seconds.

(2) Polymerization reaction The reaction mixture of S#, which was homogeneously mixed in the instant mixer of (1), was passed through the can and piping into a twin-shaft reactor which was a polymer plate. The twin-screw reactor used here is a co-rotating type reactor, which is commercially available under the trade name of KRC Kneader #5 type (Kurimoto Iron Works).

Cooling water at 15°C was passed through the jacket of the twin-shaft reactor.
The heat of polymerization was removed.

A polymer containing 10% by weight of unreacted trioxane was taken out as a powder from the outlet of the twin-screw reactor. The temperature of this powder was 70°C.

(3) Catalyst deactivation/stabilization The powder taken out from the outlet of the twin-screw reactor in (2) is
Five-layered triethylamine was introduced into the water to deactivate the polymerization catalyst. The polymer and water were separated and then the polymer was dried. This polymer had the following physical properties.

Reduced viscosity 3.50 β 20 X 10-10-5 (/mo1.
Envy, hydride, seen from the value of CH2O) β
There are very few shifts. This is the result of uniform mixing and heat removal in the heating rock for 1 iyt.

The polymer was stabilized at 200 DEG C. in a single screw extruder after adding O-5 M it % of tributylamine' and 2.5 parts by weight of water. Rv of polymer after stabilization
was 99.8%, indicating excellent thermal stability.

Comparative Example 1 (4) Polymerization Reaction The same amounts of trioxane, ethylene oxide, Hensen, and boron trifluoride dipteretherate as in Example 1 were introduced through the feed nozzle in a direct polymerization manner without homogeneous mixing. The tip of the ethylene oxide, boron trifluoride dibutyl agelate companion nozzle was constantly flushed with a stream of trioxane. The trioxane feed was heated such that the temperature of the trioxane-rich stream at the polymerization inlet was maintained at 85°C. The residence time of the trioxane-rich stream from the tip of the supply nozzle of ethylene oxide and boron trifluoride dibutyl etherate to the polymerization machine was 1.2 seconds.

The polymerization machine used here was the same KRC kneader as in Example 1.
It is type #5. Cooling water f at 15 DEG C. was poured into the jacket of this kneader to remove the combined heat.

From the outlet of the kneader, unreacted tri-xane was heated to 17N.
A polymer containing fig% was taken out as a powder. The temperature of this powder was 113°C.

(5) Catalyst deactivation/stabilization The monomer taken out from the outlet of the kneader in (4) was operated in the same manner as in Example 1 to deactivate the catalyst. It has become old and stabilized.

This polymer has the following physical properties.

(hereinafter referred to as residual color) Reduced viscosity 2.26 β 1o5 x 1o-5 (mo4/moLCH
20) Rv 96.4 (Part 1) As can be seen from the value of reduced viscosity and β, the hydride shift is larger than in Example 1, and the molecular weight is significantly lowered. At the same time, the thermal stability of the polymer is also poorer than in Example 1.

Example 2 (6) Uniform mixing (example using a static mixer) The following amounts of monomer, polymerization catalyst, and polymerization solvent were supplied to a static mixer.

The polymerization catalyst diluted with polymerization solvent was fed into the monomer stream before the static mixer.

Trioxane 5 K9/hr Ethylene glycol formal IB5 f'r/h
rCyclohexane 0.4 L/hrBF3
0Et2 0.45 fr/hr The static mixer used here has 146 cross-shaped baffles inside, an inner diameter of 8-ψ, a length of 1.50fi, and an effective space of 8.
It is a pipe type with fi 45.3 me.

Cooling water at 16°C is passed through the jacket of the static mixer.
The initial polymerization heat was removed. The temperature of the internal liquid of the static mixer was 75°C at the inlet, 90°C at the middle, and 88°C at the outlet, and a humidity distribution of 75 to 90°C was observed. Further, the mixing time was 34 seconds.

The reaction mixture in the liquid phase state that had been homogeneously mixed in the static mixer in polymerization reaction (6) was led to the twin-shaft reactor, which is a polymerization machine, through piping.The twin-shaft reactor used here ( I≦This is the same reactor as in Example 1.

Cooling water at 25°C was passed through the jacket of the twin-shaft reactor.
The heat of polymerization was removed.

A polymer containing 14 polymers of unreacted trioxane was taken out as a powder from the outlet of the twin-screw reactor. The temperature of this powder was 65°C1] (8) Catalyst deactivation/stabilization (7) The powder taken out from the outlet of the polymerization machine in (7) was used in Example 1.
The same procedure was used to deactivate and stabilize the catalyst. The physical properties of this polymer are as follows.

3.46 β 15X10”-” (mom/ma
t, CH2O>RV 99.7 (person in charge) Also in this example, hydride shift is small.
A polymer with excellent thermal stability has been obtained.

Example 3 (9) Homogeneous mixing (example using twin-screw mixing) Trioxane, ethylene oxide, benzene, and boron tritide dioxanate were fed into a rotating twin-screw mixer at 150 rpm in the following WU combination. did.

Ethylene oxide, boron trifluoride dioxanate diluted with benzene, twin screw mixing 11. The mixture was fed into the trioxadi stream immediately before.

Tori, t Ki? 7 15 Kg/hr Ethylene oxide 405 fr/hr Benzene 1. i t7hr boron trifluoride dioxanate 4. OS'r/hr
The two-shaft mixer used here is a co-rotating type with L/D = 8.8, and has two drive shafts with convex lenses and a diameter of 5.
The paddle 0za is installed with a phase difference of 90 degrees, and the paddle rotates with a clearance of i and o between it and the casing. This biaxial mixing product is commercially available under the name KRC kneader #2 type (manufactured by Kurimoto Iron Works).

Cooling water at 24°C was passed through the jacket of the twin-screw polymerization machine to remove the initial polymerization heat. ℃, and LA antidistribution was observed at 70 to 85℃.
It took 107 seconds. ((10) Togane reaction (9)-2) 1 and 1 combination (in the table, uniform 7J6 combination 1 = - liquid phase state) The resulting polymerization table is also the same as in Example 1, and is included in the Hyōgoden.
j Is it 15 degrees Celsius in the jacket of the passenger plane? The heat of polymerization was removed by passing 6 liquids through moving water.

A polymer containing a certain amount of water was extracted as a powder.

The temperature of this powder was 73°C.

The powder taken out from the outlet of the polymerization machine for catalyst deactivation and stabilization α0) was used as actual foam example 1.
The melting medium was deactivated and stabilized using the same procedure as above. The physical properties of this polymer are as follows.

Reduced viscosity 3.53 β 21 X 10' (moL/m0L-C
H2O)RV 99.6 (H) Also in this example, the hydride shift Q is small.
I was able to get a 1-mo combination that was beaten by Jiang An's 5E characteristics.

Examples 4 to 8 Uniform mixing (example of changing the mixed poem) The same amounts of monomers, choai takumi, and heavy ax bath medium as in Example 2 were mixed in approximately 1 table in the same manner as in Fushi'9'J 2. (History 7z
, : The mixture was fed to a quiet mixture to give the polymerization 1 and S shown in Table 1.

In the static mixer used here, cooling water at 16°C was passed through the jacket of the static mixer (cross-shaped) to remove the initial polymerization heat. The temperature distribution of the internal liquid (warm temperature) is as shown in Table 1.

(I(6) Multiplying Reaction (The liquid phase reaction mixture homogeneously mixed in one static mixer was polymerized in the same manner as in Example 2.

A polymer containing unreacted trioxane shown in Table 41 was taken out as a powder from the exit of the polymerization machine.

The temperature of this powder is also shown in Table 1.

(+4) Catalyst deactivation and stabilization' (The powder taken out from the outlet of one polymerizer was operated in the same manner as in Example 2 to deactivate and stabilize the catalyst. Physical properties of this polymer are shown in Table 1.

In all Examples, high polymerization degree polyacetals with little hydride shift and good thermal stability were obtained.

Comparative Examples 2 to 4 (15) Uniform mixing (examples of too little or too much mixing time) The same amounts of monomers, polymerization catalysts, and polymerization solvents as in Example 2 were mixed in the same manner as in Example 2 to the length shown in Table 1. The mixture was fed into a static mixer having a temperature of 100% and giving the mixing times shown in Table 1.

The static mixer used here has a cross-shaped baffle plate inside and is a pipe type with an inner diameter of 8. First, the heat of polymerization was removed. The temperature distribution of the internal liquid of the static mixer is as shown in the first picture. Here, in Comparative Example 2, there was too little +it- during mixing, and the initial polymerization heat was not sufficiently released. Also, in Comparative Example 4, 2 (r
l. Because the mixing time was too long, assimilation of the reaction mixture occurred in the same section of the static mixer, which caused the static mixer to fail.

The reactants homogeneously mixed in the static mixer of α6) 1 reaction (15) were polymerized in the same manner as in Example 2.

A polymer containing unreacted trioxane shown in the first coating was taken out as a powder from the exit of the polymerization machine.

The temperature of this powder is also shown in Table 1. Q7) Catalyst deactivation/stabilization α6) The powder taken out from the exit of the polymerization machine in Example 2
The same procedure was used to deactivate and stabilize the catalyst. The physical properties of this polymer are also shown in the fifth light.

Whether the mixing time is too short or too long, there will be a lot of noidride shift, and the degree of polymerization will drop significantly. This also reduces the thermal stability of the polymer.

Below margin

Claims (1)

[Claims] (1) In a continuous polymerization reaction in which trioxane gold is homopolymerized using a Lewis acid as a catalyst, or trioxane and a cyclic ether are fully copolymerized to obtain a polyacetal,
After uniformly mixing trioxane and Lewis acid, or trioxane, cyclic ether, and Lewis acid at a temperature range of 64 to 140°C for 10 to 300 seconds, the reaction mixture is quickly fed to the polymerization machine while maintaining the liquid phase state. k'! ￥ 6K
Continuous polymerization method of trioxane (i) (2) Uniform mixing is performed using a stirring mixer (3) Continuous +'4Q polymerization method of trioxane according to claim 1 (3) Uniform mixing is static mixing Continuous ffje M method for trioxane as described in box 1 of the patent claim (1) in which the homogeneous mixing is performed using a twin-screw mixer (static mixer) Continuous polymerization method for trioxane according to claim 1 (5) The polymerization machine is a twin-screw reactor, claim 1
Continuous polymerization method for trioxane according to claim 1 (6) The continuous polymerization method for trioxane according to claim 1, wherein the polymerization solvent is mixed in a proportion of 30% by weight or less with respect to trioxane (7) The Lewis acid is Continuous polymerization method of trioxane according to claim 1, which is boron trifluoride or a boron trifluoride coordination compound, (8) boron trifluoride or a boron trifluoride coordination compound, per mole of trioxane, ! 1) IXIO'~5X10
``The ratio of trioxane according to claims 1 and 7 mixed in a molar ratio %t'' 4 Law (9)
The cyclic ether is ethylene oxide or ethylene glycol formal: rJ Continuous ffEi method for trioxane as described in claim 1. Ethylene oxide or ethylene glycol formal is mixed in a ratio of 2X10" to 1X10' mole per mole of trioxane. Continuous polymerization method for trioxa as described in Claims 1 and 9