JP2936414B2 - Isobutylene-based polymer with functional end - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a halogen-terminated isobutylene-based polymer.

2. Related Art and Problems Thereof End-functional polymers, for example, polymers having hydroxyl groups introduced at both molecular ends, are useful as raw materials for polyurethane, adhesives, modifiers, coating agents, sealing agents, and the like.

One of such polymers, for example, a method for producing a terminal-functional isobutylene-based polymer includes 1,4-bis (α-chloroisopropyl) benzene (hereinafter referred to as “p-DC
C) is used as an initiator / chain transfer agent, and BCl ₃ is used as a catalyst to carry out cationic polymerization of isobutylene (US Pat. No. 4,276,394).

The isobutylene-based polymer having chlorine atoms at both ends obtained by such an inifer method can be easily converted to a polymer having an isopropenyl group at both ends by a dehydrochlorination reaction, or easily by a hydroboration reaction. It is converted into a polymer having a hydroxyl group bonded to a primary carbon at both ends.

However, according to the above-described inifer method, the polymerization temperature is as low as −50 to −70 ° C., and the monomer concentration is 1%.
Even when isobutylene is polymerized under strict reaction conditions of a dilute state of about mol / mol, several undesired side reactions cannot be avoided, and the desired terminal group containing a chlorine atom Besides, various terminal groups by side reaction as well as (An indanyl group)), and a considerable amount of the polymer having a molecular weight distribution (w /
n) also has a problem that it is about 1.5 or more. Further, in the inifer method, expensive BCl ₃ is used as a catalyst. Thus, when the above-mentioned inifer method is applied using inexpensive TiCl ₄ as a catalyst, there is a problem that the product by a side reaction further increases as compared with the case where BCl ₃ is used.

Means for solving the problem That is, the present invention provides Wherein R ¹ and R ² are the same or different and each represent a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, and X represents a halogen atom. % Of an isobutylene-based polymer containing 50 to 0% by weight of a cationically polymerizable monomer unit copolymerizable with isobutylene.

In the present specification, the cationically polymerizable monomer containing isobutylene is not limited to a monomer composed of only isobutylene, but may be 50% by weight of isobutylene.
(Hereinafter simply referred to as “%”) means a monomer in which the following is substituted with a cationically polymerizable monomer copolymerizable with isobutylene.

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 them, 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-stilstyrene, 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,
For example, propylene, 1-butene, 2-butene, styrene, butadiene, isoprene, cyclopentadiene and the like are suitable. One of these cationically polymerizable monomers copolymerizable with isobutylene may be used alone with isobutylene, or two or more thereof may be used in combination.

The initiator / chain transfer agent used in producing the polymer of the present invention has a halogen atom, and has a compound or a halogen atom in which the carbon atom to which the halogen atom is bonded is bonded to an aromatic ring carbon. And a compound in which the carbon atom to which the halogen atom is bonded is a tertiary carbon atom (hereinafter, these compounds are referred to as “halogen compounds”).
Such a halogen compound is a compound which functions as an initiator or a chain transfer agent for cationic polymerization since it easily generates a carbon cation. Examples of such a halogen compound include compounds represented by the general formula (I) AYn (I) wherein A represents a group having 1 to 4 aromatic rings. Y is a group (Where R ¹ and R ² are the same or different and are a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, and X is a halogen atom)
And a group bonded to the aromatic ring represented by n shows the integer of 1-6. A compound represented by the general formula (II) BZm (II) wherein B represents a hydrocarbon group having 4 to 40 carbon atoms. Z represents a halogen atom bonded to a tertiary carbon atom. m is 1
Indicates an integer of 4. And oligomers having an α-halostyrene unit.

In the general formula (I), A which is a group having 1 to 4 aromatic rings may be formed by a condensation reaction or may be a non-condensed one. Specific examples of such a group having an aromatic ring include, for example, a monovalent to hexavalent phenyl group,
Examples include a biphenyl group, a naphthalene group, an anthracene group, a phenanthrene group, a pyrene group, a Ph- (CH ₂ ) 1 -Ph group (Ph is a phenyl group, and 1 is an integer of 1 to 10). These groups having an aromatic ring are substituted with a straight-chain and / or branched aliphatic hydrocarbon group having 1 to 20 carbon atoms or a group having a functional group such as a hydroxyl group, an ether group or a vinyl group. You may. In the general formula (I), R ¹ and R ²
Is a monovalent hydrocarbon group, these groups are a hydroxyl group,
It may be substituted with a group having a functional group such as an ether group or a vinyl group, and the halogen atom represented by X includes a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like.

In the above general formula (II), B is a hydrocarbon group having 4 to 40 carbon atoms, preferably an aliphatic hydrocarbon group. When the number of carbon atoms of the hydrocarbon group represented by B is less than 4, the carbon atom bonded to the halogen atom is not a tertiary carbon atom, and the polymerization reaction hardly proceeds. Further, a halogen atom represented by Z includes a fluorine atom,
Chlorine, bromine, iodine and the like are included.

Examples of the oligomer having an α-halostyrene unit include an oligomer of α-chlorostyrene and an oligomer obtained by copolymerizing α-chlorostyrene and a monomer copolymerizable therewith.

In the initiator / chain transfer agent of the present invention, a compound having two or more halogen atoms in a bonded state (an aromatic ring is bonded to the carbon at the α-position or the carbon at the α-position is a tertiary carbon), When a compound having a halogen atom and another reactive functional group (such as a vinyl group) is used as an initiator and a chain transfer agent, a polymer having functionalities at two or more terminals, a so-called telechelic polymer can be obtained. It is very effective because it can increase the degree of terminal functionality.

Specific examples of the initiator and chain transfer agent used in producing the polymer of the present invention include, for example, Halogen atom-containing organic compounds such as oligomers of α-chlorostyrene, and the like. -C (CH ₃ ) ₂ that easily produces stable carbon cations such as
Cl or -C (CH ₃₎ halogen-containing organic compound having ₂ Br are preferred.

These halogen compounds are components used as an initiator and a chain transfer agent, and are used alone or as a mixture of two or more in producing the polymer of the present invention. The molecular weight of the obtained polymer can be controlled by adjusting the amount of the halogen compound used. In producing the polymer of the present invention, the halogen compound is used in a proportion of usually about 0.01 to 20%, preferably about 0.1 to 10% with respect to the cationically polymerizable monomer containing isobutylene.

TiCl used in producing the polymer of the present invention
₄ is a component used as a catalyst, and the amount of use is preferably about 0.1 to 10 times, more preferably about 2 to 5 times, the number of moles of the initiator / chain transfer agent.

In producing the polymer of the present invention, the polymerization solvent is
A solvent containing an organic compound having a nitro group. Examples of the solvent include hydrocarbon solvents such as aliphatic hydrocarbons and halogenated hydrocarbons. Of these, halogenated hydrocarbons are preferred, and chlorinated hydrocarbons having a chlorine atom are more preferred. Specific examples of such aliphatic hydrocarbons include pentane and hexane, and specific examples of halogenated hydrocarbons include chloromethane, chloroethane, methylene chloride, 1,1-dichloroethane, chloroform, and 1,2-dichloroethane. Etc. can be exemplified. They are,
One type is used alone, or two or more types are used in combination. Further, a small amount of another solvent, for example, an acetate such as ethyl acetate may be used in combination.

In producing the polymer of the present invention, it is essential that such a solvent contains an organic compound having a nitro group. As the organic compound having a nitro group, conventionally known organic compounds can be widely used, for example, nitromethane, nitroethane, 1-nitropropane, 2-nitropropane,
Nitrobenzene, nitrotoluene, o-, m- or p
-Dinitrobenzene and the like. These may be used alone or in combination of two or more. Among these organic compounds having a nitro group, nitrated hydrocarbons having two or less nitro groups are preferred.

The mixing ratio of the organic compound having a nitro group and the solvent, for example, the hydrocarbon solvent is not particularly limited, but the former is usually 100 parts by weight (hereinafter simply referred to as “parts”). About 0.1 to 500 parts, preferably 0.5
It is preferable to use about 100 parts.

In producing the polymer of the present invention, there is no particular limitation, and conventional polymerization methods can be widely applied. For example, a batch method in which a polymerization solvent, a monomer, an initiator / chain transfer agent, a catalyst, and the like are sequentially charged in one container may be used, or a polymerization solvent,
A continuous method may be employed in which a monomer, an initiator / chain transfer agent, a catalyst, and the like are continuously charged into a certain system and reacted, and further removed. The organic compound having a nitro group may be added directly to the main solvent (a solvent such as a hydrocarbon solvent) or may be added to the initiator / chain transfer agent solution. The catalyst may be added with the organic compound having a nitro group and a catalyst, or the method may be used in combination.

In producing the polymer of the present invention, the polymerization temperature is preferably about −10 to −120 ° C., more preferably about −20 to −80 ° C., and the polymerization time is usually
It is about 0.5 to 120 minutes, preferably about 1 to 60 minutes. The monomer concentration at the time of polymerization is preferably 0.1 to 8 mol / about, more preferably 0.5 to 5 mol / about.

In producing the polymer of the present invention, the termination of the polymerization reaction of the cationically polymerizable monomer is not particularly limited, and any conventional means can be applied. In producing the polymer of the present invention, it is particularly preferable to terminate the polymerization reaction by adding an alcohol such as methanol.

Effect of the Invention The present invention can provide a polymer having a high content of halogen atoms at the terminals and having a narrow molecular weight distribution.

EXAMPLES Next, the present invention will be further clarified with reference to examples.

Example 1 A stirring blade, a three-way cock, and a vacuum line were attached to the pressure-resistant glass autoclave of 1, and the polymerization vessel was dried by heating at 100 ° C. for 1 hour while evacuating the vacuum line, and then cooled to room temperature. The pressure was returned to normal pressure with nitrogen using a cock.

Then, while flowing nitrogen from one of the three-way cock, 40 ml of 1,1-dichloroethane, which is a main solvent dried by a calcium hydride treatment in an autoclave using a syringe.
Was introduced. Next, 20 ml of nitroethane, an additional solvent dried by calcium chloride treatment, was introduced, and 10 ml of a 1,1-dichloroethane solution in which 2 mmol of tricumyl chloride (TCC, compound A) was dissolved was further added.

Next, a liquefied gas sampling tube made of pressure-resistant glass with a needle valve containing 7 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, after depressurizing the inside with a vacuum line,
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. Further, cooling was continued for 1 hour with stirring, and the inside of the polymerization vessel was cooled to -60 ° C.

Next, 3.2 g (17 mmol) of TiCl ₄ was added from a three-way cock using a syringe to initiate polymerization, and after 60 minutes, methanol which had been cooled to −40 ° C. or less in advance was added. The polymerization was stopped.

After termination of the polymerization, the polymerization vessel was returned to room temperature, the reaction mixture was taken out into an eggplant-shaped flask, and unreacted isobutylene, 1,1
-After distilling off dichloroethane, nitroethane and methanol and dissolving the remaining polymer in 100 ml of n-hexane,
This solution was repeatedly washed with water until the solution became neutral. Thereafter, the n-hexane solution was concentrated to 20 ml, and the concentrated solution was poured into 300 ml of acetone to precipitate and separate the polymer.

The polymer obtained in this way is again mixed with 100 ml of n-
Dissolved in hexane, dried over anhydrous magnesium sulfate, filtered, and n-hexane was distilled off under reduced pressure.
An isobutylene polymer was obtained.

While calculating the yield from the yield of the obtained polymer,
n and w / n were determined by measuring and comparing the intensity of the resonance signal of protons belonging to each structure by the GPC method (based on polystyrene) and the terminal structure by the ¹ H-NMR (300 MHz) method. The results are shown in Table 2.

Examples 2 to 10 Polymers were produced and evaluated in the same manner as in Example 1 except that the types and amounts of the initiator / chain transfer agent, the main solvent and the added solvent were changed as shown in Table 1. The results are shown in Table 2.

Comparative Examples 1 to 5 Polymers were produced in the same manner as in Example 1 except that no additional solvent was used, and the type and amount of the initiator / chain transfer agent and the main solvent were changed as shown in Table 1. ,evaluated. The results are shown in Table 2.

In Table 1 above, Example 10 and Comparative Example 5 show -30
The polymerization was carried out at ℃.

The following is clear from the results in Table 1. That is, the polymer of the present invention is an oligomer having a high terminal halogen group introduction rate and a narrow molecular weight distribution.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-6-51752 (JP, A) JP-A-2-36204 (JP, A) US Patent 4,276,394 (US, A) (58) Fields investigated (Int) .Cl. ⁶ , DB name) C08F 10/00-10/14 C08F 110/00-110/14 C08F 210/00-210/18 C08F 4/00-4/82

Claims (2)

(57) [Claims] (1) a polymer group having a group Wherein R ¹ and R ² are the same or different and each represent a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, and X represents a halogen atom. An isobutylene-based polymer containing 50 to 0% by weight of a cationically polymerizable monomer unit copolymerizable with isobutylene and having a molecular weight distribution (w / n) of 1.05 to 1.30. 2. The polymer terminal group is —C (CH ₃ ) ₂ —Cl
The polymer of claim 1 which is a group.