JP3300466B2 - Continuous production method of isobutylene polymer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for preparing an isobutylene monomer (A) from a solvent-soluble cationic polymerization initiator (B),
Monomer (C) having a different vinyl group from isobutylene
Or (A) is continuously supplied separately from (B) and (C), and mixed with a Lewis acid (D) or a reflux solution containing (D) in the first reaction step to carry out the reaction. And a method for producing an isobutylene polymer having a vinyl group at a terminal.

[0002]

2. Description of the Related Art In a method for producing an isobutylene polymer as described above, it is necessary to quickly remove the heat of polymerization which is rapidly generated in the polymerization reaction. Requires a sufficient reaction time for the reaction to proceed.

[0003] In order to satisfy this necessity, it is known that a polymerization reaction is carried out in the presence of a low-boiling inert solvent which evaporates under the reaction conditions, and is cooled by the heat of evaporation. As for the reaction for introducing a vinyl group into the terminal of the polymer, a "two-reactor two-step method" in which a polymer is once produced and then a separate batch-type reactor is used to carry out the reaction.
Manufacturing methods are known.

[0004]

A known polymerization reaction method,
In addition, the vinyl group introduction reaction method has the following disadvantages.
That is, the low-boiling inert solvent used for the polymerization reaction is a high-pressure gas at room temperature, so that it is necessary to give the device itself a considerable pressure resistance. For the vinyl group introduction reaction, two steps are required. It is complicated because it is divided.

It is an object of the present invention to find a process for the preparation of isobutylene polymers which does not have the disadvantages mentioned above.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide an isobutylene monomer (A), a cationic polymerization initiator (B) soluble in a solvent, and a monomer having a vinyl group different from isobutylene. When the body (C) is supplied to the reaction vessel, (A)
Is supplied to the reaction vessel together with (B) and (C) or (A) separately from (B) and (C) and mixed with a Lewis acid (D). It consists of a pre-reaction step in which the polymerization reaction of isobutylene is performed and heat is removed at the same time, and a post-reaction step in which the reaction solution is retained for a certain period of time to introduce a vinyl group into the polymer terminal. Is achieved by a continuous production method of isobutylene polymer, characterized in that a shell-and-tube type reactor is used, and a tubular reactor by an extrusion flow is used in the latter reaction step.

That is, the present invention provides a vinyl group-containing isobutylene polymer as one continuous step of a first step of obtaining a polymer from an isobutylene monomer and a second step of introducing a vinyl group at a polymer terminal. It is characterized by being manufactured. The present invention uses a solvent that is liquid at room temperature for the polymerization reaction in the first reaction step,
Regarding heat removal, cooling is performed by using a shell-and-tube type reactor such as that found in a heat exchanger.In the latter-stage reaction step, in the vinyl group introduction reaction, a continuous extrusion flow with the above reactor is used. The reaction is completed in one step by using a tubular reactor and having a certain residence time. Further, regarding the polymerization reaction, the reaction and heat removal can be promoted by refluxing the reaction solution.

In the pre-stage reaction step of the present invention, it is preferable that a polymerization reaction of mainly isobutylene is mainly carried out, but a copolymerization reaction or an introduction reaction with the component (C) may slightly occur. The shell-and-tube type reactor used in the present invention has a feature that a heat transfer area can be increased and is suitable for removing polymerization heat.

Further, the tubular reactor by the extrusion flow used in the present invention is characterized in that a constant residence time can be obtained in a continuous reaction. In the present invention,
The solvent of the reaction solution is not particularly limited as long as each component is soluble. Specifically, methylene chloride (boiling point: about 40 ° C.) or a mixed solvent containing methylene chloride as one component is preferably used. According to a particularly preferred method, a mixed solution of methylene chloride and normal hexane or normal heptane containing 50 to 90% by volume of methylene chloride is used.

In the present invention, if the above-mentioned reaction solution is constituted, the components to be supplied to the reactor can be introduced as desired or in a form other than a solution state, if desired. As the cationic polymerization initiator, an organic compound having at least one functional group represented by the formula (1) is preferably used.

[0011]

Embedded image

In the formula (1), R ¹ represents hydrogen, an alkyl group or an aryl group, R ² represents an alkyl group or an aryl group, and X represents a halogen, an alkoxy group or an acyloxy group. Equation (1)
The residue to which the functional group is bonded is not particularly limited, and examples thereof include ordinary aromatic ring residues and aliphatic hydrocarbon residues. As a monomer having a vinyl group different from isobutylene, a compound that has been known to be suitable for copolymerization with isobutylene, such as diolefins, is suitable.

In the present invention, the respective reaction temperatures of the first-stage polymerization reaction and the second-stage introduction reaction are in the range of -50 to -10 ° C, preferably -50 to -30 ° C. Also, (A) ~
The timing, amount, reaction temperature, and the like of the supply of each component (D) to the reactor 2 and the supply of the polymerization reaction solution to the downstream reactor 3 can be automatically controlled. The component (D) is composed of (B),
The components (C) can be introduced into the reactor by the same route as the components, but it is preferable to introduce the components into the reactor by a different route. The components (D) and (A) are separated by different routes. Need to be introduced.

The amount of (A) to (D) can be variously changed depending on the desired isobutylene polymer, but is usually in a molar ratio of (A) :( B) :( C) :( D) = 1:
It is used in the range of 0.005 to 0.01: 0.01 to 1: 0.01 to 1. Next, one embodiment of an apparatus for continuously producing an isobutylene polymer applied to the present invention will be described with reference to FIG.

The continuous production apparatus 1 for isobutylene polymer comprises:
The shell-and-tube reactor, which is the first reactor 2 used in the first reaction step I, and the tubular reactor with the jacket, which is the second reactor 3 used in the second reaction step II, are generally constituted by a reactor 2 (D) Supply the solution to the reactor 2 (D) Supply pipe 4, (B) Supply the solution, (A) and (C) (B) ・ Monomer supply pipe 5, reflux the reaction solution And a circulation pipe 7 for refluxing the reaction solution, a communication pipe 8 for communication between the first reactor 2 and the second reactor 3 and a synthesized isobutylene weight. A collection tube 9 for taking out the united portion is provided. In addition, 10 is a jacket, 11 is a refrigerant line.

Hereinafter, the method of the present invention when the above-described apparatus is applied will be described. First, (D) the Lewis acid solution is supplied to the pre-reactor 2 through the supply pipe, and simultaneously the (B) solution, (A), and (C) are continuously supplied from the (B) monomer supply pipe 5. The reaction solution is refluxed to carry out a polymerization reaction of isobutylene for 1 to 5 minutes, at the same time heat is removed from the reactor, and then the reaction solution containing the produced polymer is supplied from the connecting pipe 8 to the subsequent reactor 3, The reaction for introducing a vinyl group into the polymer is carried out for a certain period of time, usually 30 to 60 minutes. The obtained isobutylene polymer having a vinyl group is taken out of the collection tube 9.

As for the (B) monomer supply tube 5, the tube for supplying the component (A) may be separately provided, or each of the components (A), (B) and (C) may be provided separately. You may make it supply independently.

[0018]

Thus, according to the present invention, when producing an isobutylene polymer having a vinyl group at a terminal, a solvent which is liquid at room temperature is used for the polymerization reaction,
For heat removal, cooling is performed by using a shell-and-tube type reactor such as that found in a heat exchanger, and for the vinyl group introduction reaction, a tubular reactor with an extrusion flow continuous with the above-mentioned reactor is used. By providing a certain residence time, the reaction can be completed in one step, and the apparatus and steps can be simplified as compared with the prior art. Further, regarding the polymerization reaction, the reaction and heat removal can be promoted by refluxing the reaction solution.

[0019]

The present invention will be described more specifically with reference to the following examples. Example 1 A shell-and-tube type reactor having 16 1/2 inch tubes and a tube type reactor having an inner volume of about 20 liters were cooled to −30 ° C. by a refrigerator brine, and were cooled to 1, by a metering pump. 3,5-tris (α-chloroisopropyl) benzene, isobutylene, 1,9-decadiene,
The solution was fed while titanium tetrachloride was dissolved in methylene chloride. The residence time in the reactor was about 4 minutes in the shell-and-tube type reactor and about 60 minutes in the tube type reactor.
After washing the liquid taken out from the outlet of the reactor with water, the solvent was distilled off under reduced pressure, whereby an isobutylene polymer having a vinyl group at a terminal could be obtained. The number average molecular weight (Mn) and molecular weight distribution (Mw / Mn) of the obtained polymer were measured by GPC.
The amount of the introduced vinyl group and the amount of other functional groups were determined by measuring and comparing the intensity of the resonance signal of the proton belonging to each structure by the ¹ H-NMR (300 MHz) method. The results are shown in Table 1 below.

[0020]

[Table 1]

[0021]

[Brief description of the drawings]

FIG. 1 is a schematic view showing a flow sheet of an example of an apparatus for continuously producing an isobutylene polymer used in the present invention.

[Explanation of symbols]

 I First-stage reaction step II Second-stage reaction step 1 Continuous production apparatus for isobutylene polymer 2 First-stage reactor (shell-and-tube type reactor) 3 Second-stage reactor (jacket-type tubular reactor) 4 (D) Supply pipe 5 (B)・ Monomer supply pipe 6 Reaction liquid reflux pipe 7 Circulation pump 8 Communication pipe 9 Sampling pipe 10 Jacket 11 Refrigerant line

Continuation of the front page (56) References JP-A-4-154815 (JP, A) JP-A-64-11102 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08F 8 / 00-8/50

Claims (6)

(57) [Claims] 1. An isobutylene monomer (A), a cationic polymerization initiator soluble in a solvent (B), and a monomer (C) having a vinyl group different from isobutylene are supplied to a reaction vessel. In this case, (A) is fed to the reaction vessel together with (B) and (C) or (A) separately from (B) and (C) and mixed with the Lewis acid (D). The reaction solution consists of a pre-stage reaction step in which the polymerization reaction of isobutylene is carried out in the reaction solution and heat removal is simultaneously performed, and a post-stage reaction step in which the reaction solution is retained for a certain period of time to introduce a vinyl group into the polymer terminal. A continuous reactor for isobutylene polymer, wherein a shell-and-tube type reactor is used in the first-stage reaction step, and a tubular reactor by extrusion flow is used in the second-stage reaction step. 2. The method according to claim 1, wherein (A), (B), and (C) are supplied to the first-stage reaction vessel and mixed with a reflux liquid of the first-stage reaction solution to cause a reaction. The method of claim 1. 3. The method according to claim 1, wherein an organic compound having at least one functional group represented by the formula (1) is used as (B). Embedded image R ¹ in the formula (1) represents hydrogen, an alkyl group, an aryl group,
R ² represents an alkyl group or an aryl group, and X represents a halogen, an alkoxy group, or an acyloxy group. 4. The method according to claim 1, wherein a diolefin is used as said (C). 5. The method according to claim 1, wherein methylene chloride or a mixed solvent containing methylene chloride as a component is used as a solvent for the reaction solution. 6. The method according to claim 1, wherein the reaction temperature is -50 to -10.degree.