JPH0548766B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a living polymer of an aromatic vinyl compound, and more specifically, a living polymer of an aromatic vinyl compound obtained by anionically polymerizing an aromatic vinyl compound having a substituted hydroxyimino group. Regarding polymers. [Prior art] Anionic living polymers of vinyl compounds that have reactive groups such as hydroxyimino groups in their molecules have not yet been obtained due to active hydrogen and C=N-bonds in the reactive groups. It hasn't been done yet. The present inventors first protected the reactive group of an aromatic vinyl compound having a reactive group such as a hydroxyl group, an amino group, a formyl group, or a carboxyl group in the molecule with a substituent group, and then initiated anionic polymerization. It was discovered that an anionic living polymer of an aromatic vinyl compound having a protected reactive group can be obtained by reacting with a chemical agent [JP-A-59-53509; Kobunshi Proceedings, Vol. 34, 2 No. 195 (1985); Polymer Proceedings, Volume 34, No. 6, Page 1445 (1985)]. [Problems to be Solved by the Invention] An object of the present invention is to synthesize an anionic living polymer of an aromatic vinyl compound in which the hydroxyimino group of an aromatic vinyl compound having a hydroxyimino group is protected. [Means for Solving the Problems] (Summary of the Invention) As a result of extensive research, the present inventors have determined that the active hydrogen in the hydroxyimino group of an aromatic vinyl compound having a hydroxyimino group has been converted into a trialkyl group in advance. After protection with a silyl group, triarylsilyl group, etc. (hereinafter referred to as a substituted silyl group), oligo
-methylstyrene dipotassium salt, 1,1,4,4
- When a specific anionic polymerization initiator such as tetraphenylbutane dipotassium salt or 3-methyl-1,1,3-triphenylbutane potassium salt is applied,
Not only is the active hydrogen protected against the anionic polymerization active species, but it is also possible to suppress undesirable side reactions between the anionic polymerization active species and the reactive C=N-bond, and it is protected by the substituted silyl group. The present invention was completed by discovering that living polymers of aromatic vinyl compounds having hydroxyimino groups can be obtained. That is, the present invention has the following general formula: (In the formula, R ¹ represents a hydrogen atom or a methyl group,
R ² , R ³ and R ⁴ represent the same or different alkyl groups or aryl groups. ) with a repeating unit and a number average molecular weight of 500 to 500,000. (Method for producing living polymer) The living polymer () according to the present invention has the general formula (In the formula, R ¹ represents a hydrogen atom or a methyl group.)
The vinyl compound () represented by the formula R ² R ³ R ⁴ Si
- (However, R ² , R ³ and R ⁴ are the same or different alkyl groups or aryl groups) and the resulting substituted silyl group-containing vinyl compound is subjected to specific anionic polymerization. It can be produced by polymerization using an initiator. Specifically, the vinyl compound () is 4-vinylbenzaldehyde oxime and 4-(1-methylvinyl)benzaldehyde oxime,
Both are similar to the above living polymer ()
can be manufactured. The substituted silyl group-containing compound used to protect the reactive group of the vinyl compound () is a compound containing a trialkylsilyl group, an alkyl/aryl mixed trisubstituted silyl group, or a triarylsilyl group. As an example,
General formula (R ² R ³ R ⁴ Si) mX (wherein R ² , R ³ and R ⁴ are the same or different alkyl groups or aryl groups,
X represents a halogen atom or NH group, m is 1 when X is a halogen atom, and 2 when X is a NH group.
It is. ), and a specific example is:
[(CH ₃ ) ₃ Si] ₂ NH, [(C ₂ H ₅ ) ₃ Si] ₂ NH, [(iso−
C ₃ H ₇ ) ₃ Si] ₂ NH, (CH ₃ ) ₃ SiCl, (C ₂ H ₅ ) ₃ SiCl, t
−C ₄ H ₉ (CH ₃ ) ₂ SiCl, iso−C ₃ H ₇ (CH ₃ ) ₂ SiCl,
CH ₃ (C ₂ H ₅ ) ₂ SiCl, (n-C ₄ H ₉ ) ₃ SiCl,
[(C ₆ H ₅ ) ₃ Si] ₂ NH, [C ₆ H ₅ (CH ₃ ) ₂ Si] ₂ NH,
_{( C2H5 ) 2C6H5SiCl ,} etc. can be listed. These compounds are
Two or more types can also be used simultaneously. The contact between the vinyl compound () and the substituted silyl group-containing compound is usually carried out at room temperature or under heating at a temperature of 0.5 to 50%.
Time is done. The contact may be carried out in a solvent or under an atmosphere of an inert gas such as nitrogen gas. Suitable solvents include N,N-dimethylformamide and tetrahydrofuran (hereinafter referred to as
Abbreviated as THF. ), N-methylpyrrolidone, sulforane, dimethylsulfoxide, and the like. The contact ratio of the substituted silyl group-containing compound is 0.5 times or more, preferably 1 to 10 times the mole of the vinyl compound (). By doing so, the active hydrogen in the reactive group of the vinyl compound () is substituted with the substituted silyl group to become a substituted product of the vinyl compound (), which is then reacted in the presence of a specific anionic polymerization initiator. , a living polymer of the substituted product is obtained by anionic polymerization. The specific anionic polymerization initiator used in the anionic polymerization of the substituted product is specifically oligo α-
Methylstyrene dipotassium salt, 1,1,4,4-
Examples include tetraphenylbutane dipotassium salt and 3-methyl-1,1,3-triphenylbutane potassium salt. The anionic polymerization is carried out at -100°C to room temperature, preferably -30°C or lower, particularly preferably -50 to -100°C for 0.1 to 24 hours. The polymerization reaction may be carried out without a solvent, but is preferably carried out in the presence of a solvent. Suitable solvents include THF, hexane, toluene, cyclohexane, pentane, benzene and the like, and two or more of these may be used in combination. Furthermore, the polymerization system must be maintained in an inert gas atmosphere or under reduced pressure, particularly preferably under high vacuum, free of moisture and oxygen that would interfere with the polymerization reaction. The molecular weight of the living polymer () can be controlled by changing the ratio of the substituent/anionic polymerization initiator, and the molecular weight can be increased by increasing the ratio. The resulting living polymer () typically has a molecular weight of about 500 to about
500,000, preferably from about 2,000 to about 200,000, particularly preferably from about 5,000 to about 100,000,
It has an extremely narrow molecular weight distribution with a ratio of weight average molecular weight/number average molecular weight close to 1. [Effects of the Invention] When the living polymer () of the present invention is brought into contact with a proton donor such as methanol, ethanol, phenol, hydrochloric acid, or sulfuric acid, the substituted silyl group that is a protective group is easily removed, and the vinyl compound ( ) polymers can be produced. By this method, a new polymer of the vinyl compound () can be easily produced, and since the molecular weight can be easily adjusted in this production method, the obtained polymer has an arbitrary molecular weight and a narrow molecular weight distribution. It has the characteristic of having. The thus obtained deprotected polymer is
Due to the chelate-forming ability of the hydroxyimino group, it can be used as a functional polymer to trap heavy metal ions, or new polymers with reactive substituents converted to other polar groups such as cyano, amino, formyl, carboxyl, etc. It is also useful as a raw material for the synthesis of functional polymers. EXAMPLES Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not limited thereto. [Example 1] (Polymerization apparatus used for anionic polymerization) After freezing, the anionic polymerization initiator solution and monomer solution used for anionic polymerization were degassed in a high vacuum line and sealed in an ampoule with a break seal. Anionic polymerization is carried out using the equipment shown in the drawing, in which a flask connected to a high vacuum line is connected to the above ampoules containing multiple anionic polymerization initiator solutions and monomer solutions, and a branch pipe for taking out the waste anionic initiator solution after washing the inside of the system. This was done using the following method. First, flask 1 is kept at 10 ^-5 mmHg for 5 hours to degas it, and the vacuum line 6 is sealed at point A. Then, the seal of ampoule 2 containing one anionic polymerization initiator solution is broken, and flask 1 is contained. The inside of the system was thoroughly washed and led to a branch pipe 5, which was sealed off at point B. Next, the flask 1 was cooled to -78°C, the seal of the ampoule 3 containing the second anionic polymerization initiator solution cooled to -78°C was broken, the anionic polymerization initiator was introduced into the flask 1, and then - 78
The monomer cooled at .degree. C. was similarly introduced into flask 1 from ampoule 4 and reacted for 10 minutes. The purified polymer was subjected to post-treatment and then subjected to characterization. (Synthesis and identification of O-(t-butyldimethylsilyl)-4-vinylbenzaldehyde oxime (abbreviated as VBO-tBuSi)) 4-vinylbenzaldehyde oxime

t-Butylchlorodimethylsilane [(CH ₃ ) ₃ C(CH ₃ ) ₂ SiCl] in N,N-dimethylformamide was added, and the mixture was stirred at 0°C for 1 hour and at 25°C for 12 hours under a nitrogen gas atmosphere. Then, the reaction mixture was added to a 5% by weight sodium hydroxide solution, and the product was extracted with dichloromethane and distilled under reduced pressure to obtain 84% O-(t-butyldimethylsilyl)-4-vinylbenzaldehyde oxime (VBO-tBuSi). VBO-tBuSi was further purified by vacuum distillation in the presence of Grignard reagent (C ₆ H ₅ CH ₂ MgCl).
This VBO-tBuSi had a boiling point of 94-95°C/1 mmHg. VBO−tBuSi by ^1H NMR (60MHz,
(in CDCl ₃ , TMS standard), and the following chemical shift values were determined. 0.23ppm (s; 6H, O-Si- CH3 ), _0.99ppm
(s; 9H, Si-C-C H3 ) _, 5.25-5.73ppm (2d;
2H, J = 11Hz, 18Hz, C H ₂ =), 6.73ppm (2d;
1H, C H =), 7.19-7.70ppm (m; 4H,
Aromatic), 8.18 ppm (s; 1H, -C H =N-). From this chemical shift value, it was confirmed that VBO-tBuSi has the following structure. (Synthesis and Identification of Living Polymer of VBO-tBuSi) VBO-tBuSi was polymerized in THF at -78°C for 10 minutes using various anionic polymerization initiators shown in Table 1. In both cases, the polymerized system exhibited a slightly dark red color characteristic of living anions. The produced living polymer was post-treated to obtain poly[O-(t-butyldimethylsilyl)-4-vinylbenzaldehyde oxime] (PVBO- tBuSi) was obtained quantitatively. The results of ¹ H NMR analysis and IR analysis of PVBO-tBuSi are shown below. ^1H NMR: 0.21ppm (s; 6H, O-Si- CH
₃ ), 1.00ppm (S; 9H, Si-C- CH3 ) _, 0.50~
2.00ppm (broad; 2H, -CH2 _- CH-), 0.50~
2.00ppm (broad; 1H, _-CH2 - CH- ), 6.10~
7.50ppm (broad; 4H, Aromatic), 8.05ppm
(s; 1H, -C H =N-). IR: 1613 and 1513 cm ^-1 (benzene ring endoskeletal vibration),
1393 and 1364 cm ^-1 [-C(CH ₃ ) ₃ ], 1254 and 833
cm ^-1 (Si-C), 1660 cm ^-1 (-CH=N-) From these analysis results, it was confirmed that PVBO-tBuSi has the following structure. (In the structural formula, n
indicates an integer greater than or equal to 2. ) PVBO-tBuSi is soluble in THF, methyl ethyl ketone, benzene, toluene, ethyl acetate, diethyl ether, chloroform, acetone, dioxane, and pyridine, and insoluble in hexane, N,N-dimethylformamide, dimethyl sulfoxide, ethanol, methanol, and water. It was hot. The intrinsic viscosity measured by dissolving PVBO-tBuSi in THF at 40℃ and the GPC (Gel Permation Chroma) measured at 40℃ using THF as a solvent.
The number average molecular weight was determined by the general purpose calibration curve method from the outflow curve of the tography) and is shown in Table 1.
The measured number average molecular weight of PVBO−tBuSi is VBO
It can be seen that this value agrees fairly well with the number average molecular weight calculated from the molar ratio of -tBuSi/anionic polymerization initiator. GPC measurements were conducted on PVBO-tBuSi, and the value of weight average molecular weight/number average molecular weight determined from the outflow curve was close to 1, confirming that it is a polymer with an extremely narrow molecular weight distribution. From these analysis results, it is clear that the polymer obtained by anionic polymerization of VBO-tBuSi is VBO-tBuSi.
It was proven to be a living polymer with repeating units of tBuSi. 1.0 mol/liter of PVBO-tBuSi with protecting group [CH ₃ (CH ₂ ) ₃ ] ₄ NF (tetra fluoride n-
The protecting group t-
The butyldimethylsilyl group is removed, and poly(4
-vinylbenzaldehyde oxime) (PVBO)
was gotten. As a result of ¹ H NMR analysis and IR analysis of PVBO, no characteristic absorption based on the t-butyldimethylsilyl group was observed, and it was confirmed that PVBO had the following structure. (In the structural formula, n represents an integer of 2 or more.)

[Example 2]

(Synthesis and identification of O-(trimethylsilyl)-4-vinylbenzaldehyde oxime (VBO-TMS)) 4-vinylbenzaldehyde oxime (VBO)
[(CH ₃ ) ₃ Si] ₂ NH (hexamethyldisilazane) in an equimolar amount to VBO was added to an 80% by weight N,N-dimethylformamide solution, and the mixture was heated under a nitrogen gas atmosphere.
Stirring was performed at 25°C for 12 hours. The product was then distilled under reduced pressure to obtain O-(trimethylsilyl)-4-vinylbenzaldehyde oxime (VBO-TMS).
VBO-TMS was obtained with a yield of 86% and further purified by vacuum distillation in the presence of Grignard reagent (C ₆ H ₅ CH ₂ MgCl). This VBO
-TMS had a boiling point of 82-83°C/1 mmHg. VBO-TMS was ^1H NMR (200MHz, CDCl
The following chemical shift values were determined. 0.29ppm (s; 9H _, Si- CH3 ), 5.29-5.79ppm
(2d; 2H, J = 11Hz, 17Hz, CH ₂ =), 6.70ppm
(2d; 1H, C H =), 7.24-7.58ppm (m; 4H,
aromatic), 8.17 ppm (s; 1H, -C H =N-). From this chemical shift value, it was confirmed that VBO-TMS has the following structure.
(In the structural formula, n represents an integer of 2 or more.) (Synthesis and identification of living polymer of VBO-TMS) Anionic polymerization was performed using the same polymerization apparatus and polymerization operation as in Example 1. Using 0.230 mmol of 1,1,4,4-tetraphenylbutane dipotassium salt as an anionic polymerization initiator, 4.05 mmol of
VBO-TMS was polymerized in THF at -78°C for 5 minutes. The polymerized system exhibited a slightly blackish red color characteristic of living anions. By adding a few drops of methanol to this living polymer and then treating it with a small amount of 2N hydrochloric acid at room temperature, the trimethylsilyl protecting group is removed and poly(4-vinylbenzaldehyde oxime) (PVBO) is quantitatively obtained. It was done. As a result of ¹ H NMR analysis of PVBO, no signal derived from the proton of the trimethylsilyl group was observed, and it was confirmed from the proton ratio of each signal that PVBO had the following structure. Also, PVBO
The IR spectrum of is 3100-3500 cm ^-1 (-OH),
1612 and 1518 cm ^-1 (benzene ring endoskeleton), 1640 cm ^-1

It showed the characteristic absorption of [Formula] and supported the following structure. (In the structural formula, n represents an integer of 2 or more.) The obtained PVBO was acetylated with acetic anhydride in a pyridine solvent, purified by a reprecipitation method, and then dried to obtain acetylated PVBO. Acetylated PVBO was analyzed by ¹ H NMR, and it was confirmed from the proton ratio of each signal that PVBO was quantitatively acetylated. This acetylation
Intrinsic viscosity measured at 40℃ with PVBO dissolved in THF and also measured at 40℃ with THF as solvent
The number average molecular weight was determined from the GPC runoff curve using the general purpose calibration curve method. The measured number average molecular weight of acetylated PVBO was 6,700, which was in fairly good agreement with the number average molecular weight of 7,200 calculated assuming that all hydroxyimino groups in PVBO were acetylated. Perform GPC measurements on acetylated PVBO,
The value of weight average molecular weight/number average molecular weight determined from the outflow curve was 1.16, confirming that the polymer had an extremely narrow molecular weight distribution. From these analysis results, the polymer obtained by anionic polymerization of VBO-TMS is
It was proven that it is a living polymer with repeating units of TMS.

[Brief explanation of the drawing]

The figure schematically shows an apparatus for carrying out anionic polymerization in the present invention. 1... Flask, 2, 3... Ampoule filled with anionic polymerization initiator solution, 4... Ampoule filled with monomer solution, 5... Branch pipe, 6... Vacuum line, 7... Kotoku, 8
...Magnet.

Claims (1)

[Claims] 1. General formula (In the formula, R ¹ represents a hydrogen atom or a methyl group,
R ² , R ³ and R ⁴ represent the same or different alkyl groups or aryl groups. ) is a new living polymer with a number average molecular weight of 500 to 500,000.