JP2010065081A - Novel polymer and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a novel polymer and to provide a method for producing the novel polymer. <P>SOLUTION: An end-modified polymer represented by formula (1) is provided (wherein R<SP>1</SP>and R<SP>2</SP>each independently represent a monovalent organic group or R<SP>1</SP>and R<SP>2</SP>may combine to form a ring structure with an adjacent carbon atom; R<SP>4</SP>is a hydrogen atom or a methyl group and R<SP>5</SP>represents a monovalent organic group; R<SP>6</SP>represents a monovalent organic group; R represents a hydrogen atom or a protective group; l represents a number of 1-10; m represents a number of 10-1,000; and n represents a number of 1-5). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a novel polymer and a method for producing the same.

A great deal of efforts have been made to control radical polymerization, and in recent years, reversible addition-fragmentation chain transfer polymerization (RAFT) (Non-Patent Documents 1-5), atom transfer radical polymerization (ATRP) (Non-Patent Documents 6 and 7), etc. The method has been reported. RAFT polymerization is widely used as a method for synthesizing functional polymers, almost all of which have a thiocarbonylthio group in each terminal chain after polymerization. Chen et al. Introduced functional monomer units such as coumarin dyes into RAFT agents, and using these unique RAFT polymerization methods, various functional monomer units were inserted as terminal units in the polymer chain. (Non-Patent Document 8).
Chen et al. Are studying various methods for precisely controlling the mechanical properties of polymers such as hydrogen bonding, compatibilization, macrophase separation, surface modification, and the like. And it is known that the interaction between hydrogen bonds is regarded as a pseudo-cross-linking point and can be controlled both dynamically and reversibly through temperature change.
YK Chong, J. Krstina, TPT Le, G. Moad, A. Postma, E. Rizzardo, SH Thang, Macromolecules 2003, 36, 2256-2272. J. Chiefari, RTA Mayadunne, CL Moad, G. Moad, E. Rizzardo, A. Postma, MA Skidmore, SH Thang, Macromoleules 2003, 36, 2273-2283. RTA Mayadunne, E. Rizzardo, J. Chiefari, J. Krstina, G. Moad, A. Postma, SH Thang, Macromolecules 2000, 33, 243-245. J. Chiefari, YK Chong, F. Ercole, J. Krstina, J. Jeffery, TPT Le, RTA Mayadunne, GF Meijs, CL Moad, G. Moad, E. Rizzardo, SH Thang, Macromolecules 1998, 31, 5559-5562 . YK Chong, TPT Le, G. Moad, E. Rizzardo, SH Thang, Macromolecules 1999, 32, 2071-2074. K. Matyjaszewski, J. Xia, Chem. Rev. 2001, 101, 2921. M. Kamigaito, T. Ando, M. Sawamoto, Chem. Rev. 2001, 101, 3689. M. Chen, KP Ghiggino, AWH Mau, E. Rizzardo, WHF Sasse, SH Thang, GJ Wilson, Macromolecules 2004, 37, 5479-5481.

  An object of this invention is to provide a novel polymer and its manufacturing method.

In view of such circumstances, the present inventors have succeeded in synthesizing a terminal-modified polymer represented by the following formula (1), and further have found this production method and production intermediate, thereby completing the present invention.
That is, this invention provides the terminal modification polymer represented by following formula (1).

(Wherein R ¹ and R ² represent a monovalent organic group, or R ¹ and R ² may combine to form a ring structure with adjacent carbon atoms. R ⁴ represents a hydrogen atom or methyl. R ⁵ represents a monovalent organic group, R ⁶ represents a monovalent organic group, R represents a hydrogen atom or a protecting group, l represents a number of 1 to 10, and m represents 10 to 10 1000 represents a number, and n represents a number from 1 to 5.)

Moreover, this invention reacts the compound represented by following formula (3) and the following formula (4), the compound represented by following formula (2) is obtained, and then the compound represented by following formula (2) And the compound represented by the following formula (5) are reacted, and then the protecting group represented by R ³ is substituted with a hydrogen atom, if necessary, represented by the above formula (1). A method for producing a terminal-modified polymer is provided.

(Wherein R ¹ , R ² , R ^6, l and n represent the same as described above, and R ³ represents a protecting group.)

(In the formula, R ⁴ represents a hydrogen atom or a methyl group, and R ⁵ represents a monovalent organic group.)

  The terminal-modified polymer of the present invention has good miscibility with thermoplastic resins such as poly (alkyl methacrylate), and according to the production method of the present invention, the terminal-modified polystyrene can be advantageously produced industrially. .

The terminal-modified polymer of the present invention is represented by the following formula (1).

(Wherein R ¹ and R ² represent a monovalent organic group, or R ¹ and R ² may combine to form a ring structure with adjacent carbon atoms. R ⁴ represents a hydrogen atom or methyl. a group, .R ⁶ R ⁵ is showing a monovalent organic group, .R showing a monovalent organic group is a number of .l 1 to 10 representing a hydrogen atom or a protecting group, m is 10 ~ Indicates a number of 1000, n indicates a number of 1-5)

In formula (1), R ¹ and R ² each independently represent a monovalent organic group, and examples of the organic group include a hydrocarbon group, an amide group, an acyl group, and an alkoxy group. Of these, the hydrocarbon group is preferably an aliphatic hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 30 carbon atoms, or an aromatic hydrocarbon group having 6 to 30 carbon atoms. An alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, and the like are more preferable, and a methyl group, an ethyl group, a phenyl group, and the like are particularly preferable. In addition, the amide group is a linear or branched group having 2 to 21, preferably 2 to 11, more preferably 2 to 7 carbon atoms in which one or two hydrogen atoms of the amide group are substituted with an alkyl group. And more specifically, for example, a dimethylamide group, a diethylamide group, a di-n-propylamide group, a diisopropylamide group, a di-n-butylamide group, a di-t-butylamide group, and the like. Examples of the acyl group include an acetyl group, a propionyl group, a butyryl group, a valeryl group, a benzoyl group, a trioyl group, and a caproyl group. Examples of the alkoxy group include 1 to 20 carbon atoms, preferably 1 To 10 and more preferably 1 to 6 linear, branched or cyclic alkoxy groups. More specifically, for example, methoxy group, ethoxy group, propoxy group Examples thereof include a xy group, an isopropoxy group, a butoxy group, a secondary butoxy group, a tertiary butoxy group, a pentyloxy group, and a hexyloxy group.
Examples of the ring formed by combining R ¹ and R ² together with the adjacent carbon atom include a saturated or unsaturated cyclic hydrocarbon group having 5 to 8 carbon atoms, specifically, cyclopentyl and cyclohexyl groups. Etc.
R ⁴ represents a hydrogen atom or a methyl group.
R ⁵ represents a monovalent organic group, and examples of the organic group include a hydrocarbon group, an alkoxy group, and an aryloxy group. Of these, the hydrocarbon group is preferably an aliphatic hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 30 carbon atoms, or an aromatic hydrocarbon group having 6 to 30 carbon atoms. More preferred are an alkyl group having 1 to 12, an alkenyl group having 2 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, and a methyl group, an ethyl group, an isopropyl group, an n-butyl group, a sec-butyl group. , T-butyl group, phenyl group, benzyl group and the like are particularly preferable. Examples of the alkoxy group include a linear, branched or cyclic alkoxy group having 1 to 20, preferably 1 to 10, carbon atoms, and more specifically, for example, a methoxy group, an ethoxy group, Examples thereof include a propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a t-butoxy group, a pentyloxy group, and a hexyloxy group. The aryloxy group has 6 to 30 carbon atoms, preferably 6 to 12 carbon atoms, and is preferably a phenoxy group, 2-methylphenoxy group, 4-methylphenoxy group, 4-methoxyphenoxy group, 3-phenoxy group. A phenoxy group is particularly preferred.
R ⁶ represents a monovalent organic group, and examples of the organic group include a hydrocarbon group, an alkoxy group, and an aryloxy group. Of these, the hydrocarbon group is preferably an aliphatic hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 30 carbon atoms, or an aromatic hydrocarbon group having 6 to 30 carbon atoms. An alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, and the like are more preferable, and a methyl group, an ethyl group, a phenyl group, a benzyl group, and the like are particularly preferable. Examples of the alkoxy group include linear, branched or cyclic alkoxy groups having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms. Methoxy group, ethoxy group, propoxy group, isopropoxy group, n-butoxy group, sec-butoxy group, t-butoxy group, pentyloxy group, hexyloxy group and the like. The aryloxy group has 6 to 30 carbon atoms, preferably 6 to 12 carbon atoms, and is preferably a phenoxy group, 2-methylphenoxy group, 4-methylphenoxy group, 4-methoxyphenoxy group, 3-phenoxy group. A phenoxy group is particularly preferred.
The value of l represents a number of 1 to 10, more preferably 1 to 5, and particularly preferably 1. Although the value of m shows the number of 10-1000, when using the novel polymer obtained by making it compatible with other resin, it is preferable that it is 10-200 from a miscibility viewpoint, and especially 20-100. It is preferable that n represents a number of 1 to 5, but 1 is preferable.

The terminal-modified polymer represented by the formula (1) includes, for example, a step of obtaining a compound represented by the following formula (2) by reacting a compound represented by the following formula (3) and the following formula (4): Next, the compound represented by the following formula (1-1) is obtained by reacting the compound represented by the following formula (2) with the compound represented by the following formula (5) (step 2). -1) If necessary, the protective group represented by R ³ can be substituted with a hydrogen atom to obtain a compound represented by the following formula (1-2) (step 2-2).

(In the formula, R ¹ , R ² , R ⁶ , l and n are the same as described above. R ³ represents a hydrogen atom or a protecting group.)
Here, examples of the protecting group represented by R ³ include an alkyl group, an acyl group, an alkylsilyl group, and an alicyclic group. Examples of the alkyl group include linear or branched alkyl groups having 1 to 10 carbon atoms, i-propyl group, sec-butyl group, tert-butyl group, 1,1-dimethylpropyl group, 1-methylbutyl. Group, 1,1-dimethylbutyl group and the like are preferable.
Examples of the acyl group include an acetyl group, a propionyl group, a butyryl group, a heptanoyl group, a hexanoyl group, a valeryl group, a pivaloyl group, an isovaleryl group, a laurylyl group, a myristoyl group, a palmitoyl group, a stearoyl group, an oxalyl group, and a malonyl group. Succinyl group, glutaryl group, adipoyl group, piperoyl group, suberoyl group, azelaoil group, sebacoyl group, acryloyl group, propioyl group, methacryloyl group, crotonoyl group, oleoyl group, maleoyl group, fumaroyl group, mesaconoyl group, canphoroyl group, Benzoyl, phthaloyl, isophthaloyl, terephthaloyl, naphthoyl, toluoyl, hydroatropoyl, atropoyl, cinnamoyl, furoyl, thenoyl, nicotinoyl, Nicotinoyl group, p- toluenesulfonyl group, and mesyl group.
Examples of the alkylsilyl group include trimethylsilyl group, triethylsilyl group, tri-i-propylsilyl group, dimethyl-i-propylsilyl group, diethyl-i-propylsilyl group, dimethylethylsilyl group, t-butyldimethylsilyl group, t -Butyldiphenylsilyl group, tribenzylsilyl group, tri-p-xylylsilyl group, triphenylsilyl group, diphenylmethylsilyl group, t-butylmethoxyphenylsilyl group and the like can be mentioned.
As the alicyclic group, cyclopropyl group, cyclopentyl group, 1-methylcyclopentyl group, 1-ethylcyclopentyl group, cyclohexyl group, 1-methylcyclohexyl group, 1-ethylcyclohexyl group, cyclohexenyl group, p-methoxycyclohexyl group , Tetrahydropyranyl group, tetrahydrofuranyl group, tetrahydrothiopyranyl group, tetrahydrothiofuranyl group, 3-bromotetrahydropyranyl group, 4-methoxytetrahydropyranyl group, 4-methoxytetrahydrothiopyranyl group, 3-tetrahydro Thiophene-1,1-dioxide group, 2-methyl-2-adamantyl group, 2-ethyl-2-adamantyl group and the like cyclopropyl group, cyclopentyl group, 1-methylcyclopentyl group, 1-ethylcyclopentyl group, cyclohexyl Group, 1-methylcyclohexyl group, 1-ethylcyclohexyl group, cyclohexenyl group, p-methoxycyclohexyl group, tetrahydropyranyl group, tetrahydrofuranyl group, tetrahydrothiopyranyl group, tetrahydrothiofuranyl group, 3-bromotetrahydropyrani group Group, 4-methoxytetrahydropyranyl group, 4-methoxytetrahydrothiopyranyl group, 3-tetrahydrothiophene-1,1-dioxide group, 2-methyl-2-adamantyl group, 2-ethyl-2-adamantyl group, etc. Can be mentioned.

(In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , l, m and n are the same as described above.)

Process 1
Compound (3) was obtained by referring to the procedure described in Reference 1 (YK Chong, J. Krstina, TPT Le, G. Moad, A. Postma, E. Rizzardo, SH Thang, Macromolecules 2003, 36, 2256-2272). For example, it can be synthesized from cumyl dithiobenzoate and azoisobutyronitrile (AIBN). In the compound (2), the compound (4) is preferably reacted in an amount of 0.8 to 1.2 mol, preferably equimolar to the compound (3). As the catalyst, known ones such as azobisisobutyronitrile (AIBN), 1,1′-azobiscyclohexane-1-carbonitrile can be used. Moreover, as a solvent, well-known things, such as chlorobenzene, toluene, and benzene, can be used. The reaction temperature is preferably room temperature to 100 ° C, particularly preferably 50 ° C to 90 ° C, and the reaction time is preferably 1 to 50 hours, particularly preferably 10 to 20 hours.
In addition, the compound (2) obtained here is a novel compound and is important as a production intermediate for obtaining the compound (1).

Process 2
Here, the compound represented by the following formula (1-1) is obtained by reacting the compound represented by the formula (2) with the compound represented by the following formula (5) (step 2-1). If necessary, the protecting group represented by R ³ is substituted with a hydrogen atom to obtain a compound represented by the following formula (1-2) (step 2-2).
Examples of the compound (5) include aromatic vinyls such as styrene, α-methylstyrene, m-methylstyrene, p-methylstyrene, vinyltoluene, p-methoxystyrene, and allylbenzene; 1-propene, 1-butene Aliphatic vinyls such as 1-pentene; Alicyclic vinyls such as vinylcyclopentane and vinylcyclohexane; Aliphatic vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether and butyl vinyl ether; Cyclopentyl vinyl ether and cyclohexyl vinyl ether Alicyclic vinyl ethers; Aromatic vinyl ethers such as phenyl vinyl ether and benzyl vinyl ether;
For the reaction of compound (2) and compound (5), the same catalyst and solvent as in the reaction of compound (3) and compound (4) can be used.
The amount of the compound (5) may be appropriately determined according to m which is the number of repeating units of the target compound (1), but is preferably 10 to 1000 moles, particularly preferably 50, with respect to the compound (2). ~ 200 times mole. The reaction temperature is preferably 50 to 180 ° C., particularly preferably 80 ° C. to 150 ° C., and the reaction time is preferably 1 to 80 hours, particularly preferably 10 to 50 hours.

After this reaction, the protecting group represented by R ³ is removed. The desorption method varies depending on the type of R ³ , but may be hydrolyzed by a conventional method, for example.
The reaction product thus obtained can be purified by a conventional method.

  Hereinafter, the embodiment of the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

Example 1. Preparation of end-modified polystyrene (raw material)
Monomers: Styrene (Tokyo Chemical Industry Co., Ltd.) and 4-tert-butoxystyrene (Hokuko Chemical Co., Ltd.) were washed with 5% aqueous sodium hydroxide and purified water until the aqueous phase was completely neutralized. It was then dried using magnesium sulfate and distilled using CaH ₂ under reduced pressure before use.
Butyl methacrylate (Tokyo Chemical Industry Co., Ltd.) was distilled before use.
Solvent: Chlorobenzene (Wako Pure Chemical Industries, Ltd.) was distilled with CaH ₂ .
Initiator: 2,2-azobisisobutyronitrile (AIBN, 99%, Wako Pure Chemical Industries, Ltd.) was recrystallized from acetone.
Chain transfer agent: 2-cyanopropyl-2-yl-dithiobenzoate (CTA1) (compound of formula (3)) is described in Reference 1 (YK Chong, J. Krstina, TPT Le, G. Moad, A. Postma). , E. Rizzardo, SH Thang, Macromolecules 2003, 36, 2256-2272) and was synthesized from cumyl dithiobenzoate and AIBN. Poly (butyl methacrylate) was synthesized by free radical polymerization of butyl methacrylate and AIBN at 60 ° C. in toluene.
Mn and Mw (number of molecules and average molecular weight) of PBMA were measured by size exclusion chromatography and were 82000 and 170000, respectively.

Identification method:
The molecular weight of the polymer was measured by refractive index and size exclusion chromatography (SEC) with a UV detector (TOSOH HLC-8220 SEC system), and chloroform was used as the eluent.
The number of molecules and the molecular weight (Mn and Mw) were calculated by a calibration curve based on polystyrene having a low polydispersity.
Differential scanning calorimetry (DSC) was performed with Seiko DSC 6200 under the condition of flowing nitrogen at 20 mL / min and heating at a constant rate of 10 ° C./min.
¹ H and ¹³ C NMR spectra were measured with a Varian UNITY INOVA 400 using tetramethylsilane as an internal reference material.
The UV-visible spectrum was measured with a JASCO V-750 UV-visible near-infrared spectrophotometer.
Scanning electron microscopy (SEM) of the blend film was performed with a HITACHI S3000N scanning electron microscope equipped with a backscattered electron (BSE) detector at an acceleration voltage of 25 kV.

Step 1: Synthesis of chain transfer agent-2 (CTA2) (compound of formula (2))
The procedure reported to Chen et al. was applied to produce a chain transfer agent (CTA2) containing 1 unit of tert-butoxystyrene (BSt) (Scheme 1) (Ref. 8).

A mixture of CTA1 (3.30 g, 14.9 mmol), BSt (2.62 g, 14.9 mmol), AIBN (0.048 g, 0.29 mmol) and chlorobenzene (10 ml) was subjected to 3 cycles of solid-compression-thawing under a closed vacuum. Degassed and heated in a 70 ° C. oil bath for 24 hours.
The crude product was separated and purified by silica gel column chromatography (hexane / ethyl acetate (9/1 (v / v)) to obtain the final product (3.5 g) as an orange solid in a yield of 60%.

¹ H NMR (400 MHz, CDCl ₃ , ppm): δ 1.26 (s, 3H, -CH ₃ ), 1.35 (s, 9H, -C (CH ₃ ) ₃ ), 1.44 (s, 3H, -CH ₃ ) , 2.3-2.5 (m, 2H, -CH _2- ), 5.3 (q, 1H, -CH (Ar)-), 7.0 (dd, 2H, Ar-H), 7.3-7.4 (m, 4H, Ar- H), 7.6 (m, 1H, p-Ar-H (dithiobenzoate)), 7.9 (m, 2H, m-Ar-H (dithiobenzoate))

¹³ C NMR (100 MHz, CDCl ₃ , ppm): δ 26.8 (CH ₃ ), 28.0 (CH ₃ ), 28.9 (OC (CH ₃ ) ₃ ), 31.8 (C (CH ₃ ) ₂ CN), 45.0 (CCH ₂ CH), 52.0 (CH-Ar), 79.0 (OC (CH ₃ ) ₃ ), 124.0 (CN), 124.6, 127.0, 128.4, 129.2, 132.7, 133.0, 144.8 (Ar), 155.8 (Ar-COC (CH ₃ ) ₃ ), 226.2 (C = S)
UV-visible (CH ₂ Cl ₂ ): λ _max = 307, 496 nm.
Melting point: 69.7 ℃

Step 2: Synthesis of polystyrene having 1 unit of droxystyrene α-chain end (P-HS) The following procedure is a typical method for obtaining polystyrene (P-BS) having tert-butoxystyrene α-end group. (Scheme 2).

Scheme 2. Synthesis of polystyrene with one hydroxystyrene α-terminal group by RAFT polymerization of styrene and CTA2 (P-HS) followed by deprotection.

A mixture of styrene (14 ml, 12.614 g, 121 mmol) and CTA 2 (0.481 g, 1.21 mmol) in a glass ampoule was degassed through three solid-compression-thaw cycles. The ampoule was sealed under reduced pressure and heated at 110 ° C. for 24 hours. Polymerization was stopped by rapid cooling with liquid nitrogen, excess methanol was added to the reaction mixture to precipitate the polymer, isolated by filtration, and dried at 50 ° C. under reduced pressure. The polymer yield was calculated from the weight of the polymer insoluble in methanol by a gravimetric method.
P-BS was converted to polystyrene (P-HS) having one hydroxystyrene unit at the α chain end group by hydrolysis of the tert-butoxy group. A typical procedure for the reaction is described below.
P-BS (Mn = 6700, 4.9 g, 0.73 mmol) was dissolved in a toluene / methanol mixture (7.2 (v / v)), and concentrated sulfuric acid (97%, 0.39 g, 3.9 mmol) was added. The mixture was stirred overnight at 60 ° C. under a nitrogen stream, and 50% aqueous sodium lactate solution (3 ml, 15.5 mmol) was added for neutralization. The produced polymer P-HS was purified by two cycles of dissolving in tetrahydrofuran and precipitating with methanol, and dried under reduced pressure at 50 ° C.

Production Example Blend Film Synthesis:
A polymer blend having a composition ratio (50/50 (wt / wt)) was synthesized by a conventional solution casting method using dichloromethane as a solvent. The solution containing 5 wt% polymer mixture was stirred for 1 hour until completely dissolved and placed on a glass petri dish. The solution was slowly concentrated at room temperature for 24 hours and the resulting cast film was completely dried under vacuum at room temperature for 24 hours.

Production of polystyrene having 1 unit of hydroxystyrene at the α-chain end group:
Polystyrene (indicated as P-BS) having one tert-butoxystyrene at each α chain end was synthesized by a RAFT polymerization method at 110 ° C. with a chain transfer agent (CTA2) having a thiocarbonylthio group. The polymerization results are summarized in Table 1.

The control / original nature of this polymerization was analyzed kinetically (kinetically). FIG. 1 (a) shows that [M] ₀ / [CTA 2] ₀ = 300/1 ([M] ₀ and [CTA 2] ₀ are the initial concentrations of monomer and CTA2, respectively, and [M] t is at time t. 2 represents the change of ln ([M] ₀ / [M] t) with respect to polymer time. The plot of ln ([M] ₀ / [M] t) was a straight line and was very similar to the first order velocity equation. When the average molecular weight Mn is estimated by SEC analysis, Mn increases linearly with increasing conversion rate (Fig. 1 (b), indicating that polymerization is controlled. Polydispersity value) (PDI), Mw / Mn was kept below 1.15 during the polymerization, and the ¹ H-NMR spectrum of the obtained P-BS shows a signal specific to polystyrene and a minor signal derived from α and ω end groups. These minor signals represented the Mn value of P-BS similar to the Mn value obtained in Table 1. From these results, RAFT polymerization of styrene and CTA2 as initiators It was found that P-BS with one tert-butoxystyrene (α-chain end) unit and one dithiobenzoic acid (ω-chain end group) was obtained, which proceeded well and had low polydispersity (Scheme) 4).

As shown in Table 1, various P-BS having a molecular weight of 2200-20100 were obtained by changing the ratio of [M] ₀ / [CTA 2] ₀ . The sample names in Table 1 represent the characteristics of the synthetic P-BS, that is, the average molecular weight and the chemical structure of the α and ω terminals, respectively. For example, P-22BS has Mn = 2200, tert- It represents a polymer having a butoxystyrene unit and dithiobenzoic acid as the ω chain end group.
The tert-butoxystyrene, which is the α chain end group of polystyrene, was converted to hydroxystyrene by deprotecting the tert-butyl group at 60 ° C. under acidic conditions. It was found by ¹³ C-NMR analysis that the tert-butyl protecting group was completely removed. FIG. 3 shows ¹³ C NMR spectra before and after deprotecting P-22BS. A sharp signal at 29 ppm was attributed to the carbon atoms of the three methyl groups of the tert-butyl group and disappeared after hydrolysis. Deprotection of the tert-butyl group in P-BS proceeded quantitatively to obtain a polymer (P-HS) having one hydroxystyrene at the α chain end group.

Test example Blend with poly (butyl methacrylate):
P-HS, P-BS and P-StS (Scheme 4), which are polystyrenes with different α chain end groups but similar ω chain ends (dithiobenzoic acid), were combined with poly (butyl methacrylate) (PBMA). Blending was performed at a blending ratio of 50/50 (wt / wt). PBMA has longer chains (Mn = 82,000, Mw = 170,000) compared to polystyrene. In the case of polystyrene: P-22BS, P-22HS, P-25StS, it was found that a transparent film was formed. On the other hand, the blend film of P-HS and PBMS having Mn of 2,200-8,400 was transparent.

  Specific polystyrene (P-BS or P-HS) having 1 unit of tert-butoxystyrene or hydroxystyrene at the α-terminal is subjected to RAFT polymerization of styrene using a specific chain transfer agent, CTA2, followed by deprotection reaction. Synthesized. By controlled / uncontrolled polymerization, specific polystyrenes with Mn values of 2,200-20,100 and low PDI values (Mw / Mn = 1.9-1.16) can be obtained.

It is a figure which shows the first-order rate equation plot with respect to the polymerization time of RAFT polymerization of styrene. It is a figure which shows the NMR spectrum of a polymer. It is a figure which shows the ¹³ C-NMR spectrum of a polymer.

Claims (6)

A terminal-modified polymer represented by the following formula (1).

(Wherein R ¹ and R ² represent a monovalent organic group, or R ¹ and R ² may combine to form a ring structure with adjacent carbon atoms. R ⁴ represents a hydrogen atom or methyl. R ⁵ represents a monovalent organic group, R ⁶ represents a monovalent organic group, R represents a hydrogen atom or a protecting group, l represents a number of 1 to 10, and m represents 10 to 10 1000 represents a number, and n represents a number from 1 to 5.) Following formula (2)

(In the formula, R ¹ and R ² represent a monovalent organic group, or R ¹ and R ² may be bonded to form a ring structure with adjacent carbon atoms. R ³ represents a protecting group. And R ⁶ represents a monovalent organic group, l represents a number of 1 to 10, and n represents a number of 1 to 5.)
A method for producing a terminal-modified polymer according to claim 1, wherein the compound represented by formula (5) is reacted with a compound represented by the following formula (5).

(In the formula, R ⁴ represents a hydrogen atom or a methyl group, and R ⁵ represents a monovalent organic group.) Furthermore, the protective group shown by R < ³ > is substituted by the hydrogen atom, The manufacturing method of the terminal modified polymer of Claim 2 characterized by the above-mentioned. The compound represented by the following formula (2) is obtained by reacting the compound represented by the following formula (3) with the compound represented by the following formula (4). A method for producing the terminal-modified polymer as described.

(In the formula, R ¹ and R ² represent a monovalent organic group, or R ¹ and R ² may be bonded to form a ring structure with adjacent carbon atoms. R ³ represents a protecting group. And R ⁶ represents a monovalent organic group, l represents a number of 1 to 10, and n represents a number of 1 to 5.) A compound represented by the following formula (2).

(In the formula, R ¹ and R ² represent a monovalent organic group, or R ¹ and R ² may be bonded to form a ring structure with adjacent carbon atoms. R ³ represents a protecting group. And R ⁶ represents a monovalent organic group, l represents a number of 1 to 10, and n represents a number of 1 to 5.) The manufacturing method of the compound represented by following formula (2) characterized by making the compound represented by following formula (3) and the following formula (4) react.

(In the formula, R ¹ and R ² represent a monovalent organic group, or R ¹ and R ² may be bonded to form a ring structure with adjacent carbon atoms. R ³ represents a protecting group. And R ⁶ represents a monovalent organic group, l represents a number of 1 to 10, and n represents a number of 1 to 5.)

Images