JP2835779B2 - Method for producing isobutylene-based polymer having functional end - Google Patents

Description

The present invention relates to a method for producing an isobutylene-based polymer having a functional terminal. More specifically, in the present invention, when cationically polymerizing a cationically polymerizable monomer containing isobutylene, by reacting in the presence of a specific initiator and a metal halide, a group having various functionalities is added to a molecular terminal. The present invention relates to a method for producing existing isobutylene-based polymers.

[Problems to be solved by conventional technologies and inventions]

A polymer having a functional group such as a hydroxyl group at both ends of a linear molecule can be cured by forming a bond between the polymers using the functional group. Such a polymer is called a telechelic polymer, and is used as an adhesive, a sealing agent, a coating agent, and the like. Representative examples of the telechelic polymer include polyethers and polyesters having a hydroxyl group at a molecular terminal, and these polymers can be cured using a polyisocyanate compound.

A terminal functional polymer using polyisobutylene as the main chain of such a telechelic polymer has been proposed (US Pat. No. 4,276,394). Polyisobutylene is originally excellent in electrical properties such as weather resistance, electrical insulation and dielectric properties, gas barrier properties, and the like. Therefore, such terminal-functionalized polyisobutylene is expected to be used for various new applications.

U.S. Pat. No. 4,276,394 discloses that the terminal-functionalized isobutylene-based polymer is produced by a method called an inifer method in which isobutylene is cationically polymerized in the presence of an initiator and a catalyst. In this case, it is described that the disclosed agent used is a polyfunctional initiator and various compounds capable of generating a tertiary carbocation can be used in the inifer method.

The multifunctional initiators commonly used in the inifer method are 3
Compounds that can produce cumyl-type carbocations, which are particularly stable among the primary carbocations, specifically 1,4-bis (α-chloroisopropyl) benzene [hereinafter p-DCC
(P-dicumyl chloride). Is limited to such compounds.

However, in a system using this p-DCC, when a polymerization reaction is carried out at a temperature of -30 ° C. or higher, which is a realistic temperature when manufacturing is imagined, a polymer having an indanyl terminal is by-produced. Is pointed out [Po
lym.Bull.vol3, No.6 / 7 339 (1980) and others].

The indanyl group is formed by performing a cyclization reaction with one molecule of isobutylene added to p-DCC.

That is, when the p-DCC is used, the following three types are generated.

Since p-DCC has two polymerization initiation points, a polymer having no indanyl group, a polymer having one terminal of indanyl group, and a diindanyl compound having two indanyl groups are produced. The diindanyl compound can be removed by reprecipitation or the like, but there is a problem that a polymer having one indanyl group terminal cannot be removed.

Thus, the present inventors thought that if an initiator having only one polymerization initiation point was used, the indanyl-type by-product would not be a polymer and could be easily removed.

By the way, in order to obtain a telechelic polymer, the initiator itself must have a polymerization active site,
Generally, as described above, p-DCC or the like which generates a tertiary carbocation by the inifer method as described above is mainly used. It is said that primary and secondary carbocations are more unstable than tertiary carbocations. That is, it is said that the initiating ability of benzyl chloride or 1-phenylethyl chloride is inferior to that of cumyl chloride because the carbocation is not sufficiently stable.
[J.Polym.Sci.Polym.Chem.Ed. Vol. 15, No. 12, 2869 (197
7)].

In general, benzyl chloride-based compounds and 1-phenylethyl chloride-based compounds are not suitable as polymerization initiators for isobutylene.

On the other hand, as for the cumyl chloride-based one-point initiator, p-hydroxycumyl chloride is used. (Macromolecules, Vol. 23, 1238
(1990)]. However, there is no disclosure of the effectiveness of using this compound as an initiator.

[Means for solving the problem]

The present inventors have intensively studied one-point initiation type initiators having various functional groups in order to solve the above problems. As a result, for example, (R 'represents an alkyl group, W' represents a halogen atom), but cannot function sufficiently as an initiator with an alkyl-substituted benzyl halide compound, but an electron-donating substituent on the aromatic ring By introducing R ¹ O- (R ¹ represents a hydrogen atom or a monovalent organic group) or the like, it has a function as an initiator and is a one-point initiation type initiator having various functional groups. It has been found that the present invention has been completed.

That is, the present inventors introduce an electron-donating substituent on the aromatic ring of benzyl chloride or 1-phenylethyl chloride, which is conventionally difficult to use as an initiator, as described above. As a result, the primary and secondary chlorides were found to be effective initiators by introducing an alkoxy group, a hydroxyl group, and the like.

By finding primary and secondary one-point initiators, many new effective initiators could be obtained.
Further, benzyl chloride-based compounds have an advantage that they can be easily obtained by chloromethylation of any aromatic compound.

Further, the present inventors have studied the reaction of introducing a functional group into a polymerization termination terminal using various endcap agents. As a result, we succeeded in obtaining telechelic polymers having various functional groups.

That is, the gist of the present invention is to provide a polymerization reaction of a cationic polymerizable monomer containing isobutylene using a catalyst system comprising an initiator and a metal halide to produce an isobutylene-based polymer having a functional terminal. In the method, the initiator is represented by the general formula (I): [In the formula, R ¹ represents a hydrogen atom or a monovalent organic group, and W represents a halogen atom, an alkoxy group, an acetoxy group, or a hydroxyl group. And using at least one selected from the group consisting of BX ₃ , TiX ₄ , SnX ₄ and SbX ₅ (X represents a halogen atom) as the metal halide. A method for producing an isobutylene-based polymer having a functional terminal characterized by: (2) performing a polymerization reaction of a cationically polymerizable monomer containing isobutylene using a catalyst system comprising an initiator and a metal halide; In the process for producing an isobutylene-based polymer having the general formula (II): [In the formula, R ¹ represents a hydrogen atom or a monovalent organic group, R ² represents a monovalent organic group, and W represents a halogen atom, an alkoxy group, an acetoxy group or a hydroxyl group. And using at least one selected from the group consisting of BX ₃ , TiX ₄ , SnX ₄ and SbX ₅ (X represents a halogen atom) as the metal halide. A method for producing an isobutylene-based polymer having a functional terminal characterized by: (3) performing a polymerization reaction of a cationic polymerizable monomer containing isobutylene using a catalyst system comprising an initiator and a metal halide; In the method for producing an isobutylene-based polymer having the general formula (III): [In the formula, R ² , R ³ and R ⁴ represent a monovalent organic group, and R ² , R ³ and R ⁴ may be the same or different. W represents a halogen atom, an alkoxy group, an acetoxy group or a hydroxyl group. And using at least one selected from the group consisting of BX ₃ , TiX ₄ , SnX ₄ and SbX ₅ (X represents a halogen atom) as the metal halide. A method for producing an isobutylene-based polymer having a functional terminal, which is characterized in that: (4) The method according to any one of claims (1) to (3),
A method for producing an isobutylene-based polymer having a functional terminal, wherein a functional group is introduced into a polymerization termination terminal by adding an end gap agent to the polymerization system.

In the compounds represented by the general formulas (I) to (III), R ¹ and R ³ are specifically: And the like.

As W, specifically And the like.

As described above, as the compounds represented by the general formulas (I) to (III), specifically, Or a compound in which a Cl group bonded to a carbon atom bonded to an aromatic ring of these compounds is replaced with a Br group, an I group, a methoxy group, an ethoxy group, an acetoxy group, a hydroxyl group, or the like.

These compounds are components used as an initiator, and the molecular weight of the obtained polymer can be controlled by the amount used. In the present invention, the compound is used in an amount of usually about 0.01 to 20% by weight (hereinafter simply referred to as "%"), preferably about 0.1 to 10%, based on the cationically polymerizable monomer containing isobutylene. Good.

If the amount is less than 0.01% by weight, the molecular weight of the polymer becomes too large. On the other hand, if it is used in excess of 20% by weight, the molecular weight of the polymer becomes too small, which is not preferred.

In the present invention, examples of the metal halide include compounds represented by the general formulas BX ₃ , TiX ₄ , SnX ₄ and SbX ₅ (X represents a halogen atom).
l ₃ , TiCl ₄ , SnCl ₄ and SbCl ₅ are preferred, especially TiCl ₄ and
SnCl ₄ is preferred.

The amount of the metal halide used is preferably about 0.001 to 10 times, more preferably about 0.1 to 5 times, the number of moles of the initiator.

If it is less than 0.001 times, the yield of the polymer decreases, and 10
If used more than twice, the amount of wastewater to be treated increases, which is not preferable.

In the present specification, the cationically polymerizable monomer containing isobutylene is not limited to a monomer composed of only isobutylene, and a monomer obtained by replacing 50% or less of isobutylene with a cationically polymerizable monomer that can be copolymerized with isobutylene. means.

Examples of the cationic polymerizable monomer copolymerizable with isobutylene include olefins having 3 to 12 carbon atoms, conjugated dienes, vinyl ethers, aromatic vinyl compounds, vinyl silanes, allyl silanes, and the like. Among these, olefins having 3 to 12 carbon atoms and conjugated dienes are preferred.

Specific examples of the cationically polymerizable monomer copolymerizable with the isobutylene include, for example, propylene, 1-butene, 2-butene, 2-methyl-1-butene, 3-methyl-1-butene, pentene, and 4-methyl- 1-pentene,
Hexene, vinylcyclohexane, butadiene, isoprene, cyclopentadiene, methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether, styrene, α-methylstyrene, dimethylstyrene, monochlorostyrene, dichlorostyrene, β-pinene, indene, vinyltrichlorosilane, vinylmethyldiene Chlorosilane, vinyldimethylchlorosilane, vinyldimethylmethoxysilane, vinyltrimethylsilane, divinyldichlorosilane, divinyldimethoxysilane, divinyldimethylsilane, 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, trivinylmethylsilane , Tetravinylsilane, allyltrichlorosilane, allylmethyldichlorosilane, allyldimethylchlorosilane, allyldimethylmethoxysilane, Trimethylsilane, diallyl dichlorosilane, diallyl dimethoxysilane, diallyl dimethyl silane, .gamma.-methacryloyloxy propyl trimethoxy silane, .gamma.-methacryloyloxy propyl methyl dimethoxysilane and the like. Among these,
Propylene, 1-butene, 2-butene, styrene, butadiene, isoprene, cyclopentadiene and the like are preferred. These cationically polymerizable monomers copolymerizable with isobutylene may be used alone or in combination with isobutylene, or in combination of two or more.

In the present invention, as the polymerization solvent, conventionally known solvents can be widely used as long as they are inert solvents, and specific examples thereof include, for example, chloromethane, chloroform, carbon tetrachloride, chloroethane, methylene chloride, 1,1-dichloroethane. , 1,2-dichloroethane, 1,1,1-trichloroethane,
Chlorinated hydrocarbon compounds such as 1,1,2-trichloroethane, 1,1,2,2-tetrachloroethane, tetrachloroethylene,
Examples include nitro compounds such as n-hexane and nitroethane. These may be used alone or in combination of two or more.

When carrying out the production method of the present invention, a batch method in which a solvent, an initiator, a metal halide, and the like are charged into one container and then a monomer is added, or a solvent,
A continuous method may be employed in which a monomer, an initiator, a metal halide, and the like are continuously charged into a certain system while reacting and then further taken out.

In the production method of the present invention, the polymerization temperature is 10 to-
The temperature is preferably about 130 ° C., more preferably about −10 to −80 ° C., and the polymerization time is usually about 0.0001 to 60 minutes, preferably about 1 to 30 minutes. Further, the monomer concentration during polymerization is preferably about 0.1 to 8 mol /,
0.5 to 5 mol / about is more preferable.

In the present invention, the term “end gap agent” refers to any compound capable of causing a Friedel-Crafts reaction with a terminating terminal (having the following structure (a), (b) or (c)) of an isobutylene-based polymer.

That is, the endcapping agent represents an aromatic compound that can react with the tertiary carbocation generated from the terminal end.

As the endcapping agent, phenols, phenyl ethers, non-conjugated dienes or alkylbenzenes are usually preferable, and specific examples include the following.

The Friedel-Crafts reaction between the terminating end and the end gap agent is carried out by adding an end cap agent to the polymerization system before or after the end of the polymerization, thereby introducing various functional groups into the terminating end. Can be
In one pot, a telechelic isobutylene polymer can be obtained.

The amount of the endcapping agent to be added to the polymer system is usually 0.5 to 50 times, preferably 1 to 20 times, the number of moles of the terminal end.

Solvents for performing the polymerization reaction and the Friedel-Crafts reaction in one pot include methylene chloride, carbon tetrachloride,
Chloroform, 1,1-dichloroethane, halogenated hydrocarbons such as ethyl chloride, toluene, aromatic compounds such as chlorobenzene, nitromethane, nitroethane, nitro compounds such as nitrobenzene are preferred.
One kind may be used alone, or two or more kinds may be used in combination.

In the present invention, various Lewis acids or proton acids can be added to promote the Friedel-Crafts reaction.

As the Lewis acid, AlCl ₃ , SnCl ₄ , TiCl _{4 and the} like are preferable, and as the protic acid, H ₂ SO ₄ and CF ₃ SO ₃ H are preferable.

When producing a telechelic isobutylene-based polymer in one pot, it is preferable to carry out the polymerization reaction at -60 ° C to -10 ° C and then carry out the Friedel-Crafts reaction at 0 to 40 ° C. Depending on the conditions, it is possible to obtain a telechelic isobutylene polymer by completing the Friedel-Crafts reaction at the same time as conducting the polymerization reaction at -60 to -10 ° C.

Usually, the polymerization reaction is preferably performed for about 1 to 30 minutes, and the Friedel-Crafts reaction is preferably performed for about 0.5 to 24 hours.

In the present invention, the termination of the polymerization reaction of the cationic polymerizable monomer or the termination of the reaction between the terminal end and the endcapping agent is not particularly limited, and any conventional means can be applied. In the present invention, it is particularly preferable to stop the reaction by adding an alcohol such as methanol.

〔The invention's effect〕

(1) In general, it is said that benzyl chloride and 1-phenylethyl chloride are inferior in polymerization initiation ability of isobutylene as compared with cumyl chloride. However, the present inventors introduced a benzyl chloride compound or a 1-phenylethyl chloride compound by introducing an electron donating group such as an alkoxy group or a hydroxyl group at the para-position of an aromatic ring, thereby making it an effective initiator. Clarified.

(2) By using the method of the present invention, it has become possible to prevent the formation of a polymer having an indanyl group terminal. That is, when an indanyl group is formed, no polymerization reaction occurs, and the indanyl compound can be easily removed from the system.

This has made it possible to obtain a linear isobutylene-based polymer having a higher terminal functionalization rate.

(3) By using the method of the present invention, an allyl group,
It has become possible to use an initiator having various functional groups such as a methallyl group, a hydroxyl group, an acryl group, a chloro group and a silyl group.

(4) In the method of the present invention, a Friedel-Crafts reaction between the terminating end of the isobutylene-based polymer and the endcapping agent makes it possible to introduce various functional groups into the terminating end. Therefore, by using the method of the present invention, allyl group at both ends, silyl group,
It has become possible to obtain a telechelic isobutylene-based polymer having an acrylic group or the like.

(5) An aryl group, silyl group, or a substituent at an acrylic group end was newly introduced into the aromatic ring of the cumyl chloride-based compound, and it was revealed that these compounds are effective initiators.

In other words, the cumyl chloride-based one-point initiator was successfully made rich in variety.

〔Example〕

Hereinafter, the present invention will be further clarified with reference to examples, but the present invention is not limited to these examples.

Example 1 A three-way cock was attached to a 200 ml pressure-resistant glass container, and the polymerization container was dried by heating at 100 ° C. for 1 hour while being evacuated by a vacuum line.
The pressure was returned to normal pressure with nitrogen using a three-way cock.

Thereafter, while flowing nitrogen from one of the three-way cocks, 40 ml of methylene chloride which was a polymerization solvent dried by calcium hydride treatment was introduced into the autoclave using a syringe.

Further, 2 mmol of p-methoxybenzyl chloride was added using a syringe.

Next, a liquefied gas sampling tube made of pressure-resistant glass with a needle valve containing 5 g of isobutylene dehydrated by passing through a column filled with barium oxide was connected to a three-way cock. It was immersed in an acetone bath and cooled for 1 hour while stirring the inside of the polymerization vessel. After cooling, the pressure inside was reduced by a vacuum line, then the needle valve was opened, and isobutylene was introduced into the polymerization vessel from a pressure-resistant glass liquefied gas sampling tube. Thereafter, the pressure was returned to normal pressure by flowing nitrogen from one of the three-way cocks, and -30 ° C
The temperature in the container was lowered to -30 ° C. by immersing in a dry ice-acetone bath.

Next, a solution (−30 ° C.) of 10 mmol of tin tetrachloride diluted with 20 ml of methylene chloride was added from a three-way cock using a syringe to start polymerization.
The polymerization was stopped by adding methanol which had been cooled to below 40 ° C.

After terminating the polymerization, the polymerization solution was shaken with 100 ml of a saturated aqueous solution of sodium hydrogen carbonate, and the organic layer was washed twice with 100 ml of water. The organic layer was concentrated to 10 ml and the polymer was precipitated by adding it to 300 ml of acetone with stirring.

The polymer thus obtained was dissolved in 80 ml of n-hexane, dried over anhydrous magnesium sulfate, filtered, and n-hexane was distilled off under reduced pressure to obtain an isobutylene-based polymer.

While calculating the yield from the yield of the obtained polymer,
by GPC n and w / n, also a terminal structure ¹ H-N
It was determined by measuring and comparing the intensity of the resonance signal of the proton belonging to each structure by the MR (300 MHz) method. The results are shown in Table 1.

Examples 2 to 8 Polymers were prepared and evaluated in the same manner as in Example 1 except that 2 mmol of an initiator having various structures was used instead of p-methoxybenzyl chloride. The initiator used and the result of the polymerization reaction are shown in Table 1.

Example 9 After completion of the polymerization reaction, a polymer was produced and evaluated in the same manner as in Example 4, except that 10 mmol of allyl phenyl ether was added to the polymerization solution, and further, methanol was added after stirring at room temperature for 36 hours. did. The results are shown in Table 1.

Comparative Examples 1 and 2 A polymer was produced and evaluated in the same manner as in Example 1 except that benzyl chloride or p-methylbenzyl chloride was used in an amount of 2 mmol instead of p-methoxybenzyl chloride. The initiator used and the result of the polymerization reaction are also shown in Table 1.

From the results of Examples 1 to 8 in Table 1, it became clear that the polymerization reaction proceeds from various initiators. Further, from the results of Example 9, it was revealed that a telechelic polymer can be obtained.

Further, from Comparative Examples 1 and 2, it was confirmed that unsubstituted or alkyl-substituted benzyl chloride was not very efficient as an initiator. It can be said that, for the first time, the introduction of an alkoxy or hydroxyl group allows the benzyl chloride-based compound to have a starting ability.

Examples 10 to 12 Polymers were prepared and evaluated in the same manner as in Example 1 except that 10 mmol of various Lewis acids were used instead of tin tetrachloride. The results are shown in Table 2.

The results in Table 2 demonstrate that p-methoxybenzyl chloride is an effective initiator in systems using various Lewis acids.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) C08F 4/06-4/26 C08F 10 / 10,110 / 10,210 / 10 C08F 2/38 CAS ONLINE

Claims (4)

(57) [Claims] 1. A method for producing an isobutylene-based polymer having a functional terminal by carrying out a polymerization reaction of a cationically polymerizable monomer containing isobutylene using a catalyst system comprising an initiator and a metal halide. Formula (I): [In the formula, R ¹ represents a hydrogen atom or a monovalent organic group, and W represents a halogen atom, an alkoxy group, an acetoxy group, or a hydroxyl group. And using at least one selected from the group consisting of BX ₃ , TiX ₄ , SnX ₄ and SbX ₅ (X represents a halogen atom) as the metal halide. A method for producing an isobutylene-based polymer having a characteristic functional end. 2. A method for producing an isobutylene-based polymer having a functional end by carrying out a polymerization reaction of a cationically polymerizable monomer containing isobutylene using a catalyst system comprising an initiator and a metal halide. As general formula (II): [In the formula, R ¹ represents a hydrogen atom or a monovalent organic group, R ² represents a monovalent organic group, and W represents a halogen atom, an alkoxy group, an acetoxy group or a hydroxyl group. And using at least one selected from the group consisting of BX ₃ , TiX ₄ , SnX ₄ and SbX ₅ (X represents a halogen atom) as the metal halide. A method for producing an isobutylene-based polymer having a characteristic functional end. 3. A method for producing an isobutylene-based polymer having a functional end by carrying out a polymerization reaction of a cationically polymerizable monomer containing isobutylene using a catalyst system comprising an initiator and a metal halide. Formula (III): [In the formula, R ² , R ³ and R ⁴ represent a monovalent organic group, and R ² , R ³ and R ⁴ may be the same or different. W represents a halogen atom, an alkoxy group, an acetoxy group or a hydroxyl group. And using at least one selected from the group consisting of BX ₃ , TiX ₄ , SnX ₄ and SbX ₅ (X represents a halogen atom) as the metal halide. A method for producing an isobutylene-based polymer having a characteristic functional end. 4. The method according to claim 1, wherein a functional group is introduced into a polymerization termination terminal by adding an endcapping agent to the polymerization system. A method for producing an isobutylene-based polymer having: