JP4120267B2 - Narrowly dispersible oxystyrene copolymer and process for producing the same - Google Patents

Description

（式中、Ｘは、ハロゲン原子を、Ｒ３は、置換基を有してもよいアリール基、アリールオキシ基、アルコキシ基又はアルコキシアルコキシ基であり、基中の１つ以上の水素原子がハロゲン原子で置換されていてもよい基を表す。）で表される化合物と、ルイス酸性を有するハロゲン化金属とを開始剤とし、ｐ−ｔ−ブトキシスチレン、ｍ−ｔ−ブトキシスチレン、ｐ−（１−エトキシエトキシ）スチレン又はｍ−（１−エトキシエトキシ）スチレンから選ばれるオキシスチレン系単量体と、下記一般式（５）
【００１６】
【化１０】

（式中、Ｒ５は、アルキル基、アリール基、アリールアルキル基又はアルコキシアルキル基を表す。）で表されるビニルエーテル系単量体を共重合させる狭分散性オキシスチレン系共重合体の製造方法である。
【００１７】
以下本発明を詳細に説明する。
【００１９】
一般式（４）で表される化合物としては、ｐ−ｔ−ブトキシスチレン、ｍ−ｔ−ブトキシスチレン、ｐ−（１−エトキシエトキシ）スチレン、ｍ−（１−エトキシエトキシ）スチレンである。これらは単独で用いられてもよいし、併用されてもいい。
【００２０】
本発明で使用される一般式（５）中のＲ５は、アルキル基、アリール基、アリールアルキル基又はアルコキシアルキル基であり、基中の１つ以上の水素原子がフッ素原子で置換されていてもよい基を表す。更に詳しくは、炭素数１〜２０の直鎖状、分岐状又は環状構造を有してもよいアルキル基、炭素数６〜２６のアリール基、炭素数７〜２７のアリールアルキル基、炭素数１〜３０の直鎖状、分岐状又は環状構造を有していてもよいアルコキシ基を有するアルコキシアルキル基であり、基中の１つ以上の水素原子がフッ素原子で置換されていてもよい化合物を用いることができる。アリール基はアルキル基、アルコキシ基等の置換基を有していてもよく、また、アルコキシアルキル基としては、テトラヒドロピラニルの様な環中に酸素原子を有する化合物も含む。
【００２１】
一般式（５）で表される化合物としては、メチルビニルエーテル、エチルビニルエーテル、ｎ−プロピルビニルエーテル、ｉ−プロピルビニルエーテル、ｎ−ブチルビニルエーテル、ｉ−ブチルビニルエーテル、ｎ−アミルビニルエーテル、ｉ−アミルビニルエーテル、２−エチルヘキシルビニルエーテル、シクロヘキシルビニルエーテル、１−アダマンチルビニルエーテル、２−アダマンチルビニルエーテル、トリフルオロメチルビニルエーテル、ペンタフルオロエチルビニルエーテル、２，２，２−トリフルオロエチルビニルエーテル、フェニルビニルエーテル、４−メチルフェニルビニルエーテル、４−トリフルオロメチルフェニルビニルエーテル、４−フルオロフェニルビニルエーテル、ベンジルビニルエーテル、４−フルオロベンジルビニルエーテル、２−メトキシエチルビニルエーテル、２−エトキシエチルビニルエーテル、２−テトラヒドロピラニルビニルエーテル等を挙げることができる。これらは単独で用いられてもよいし、併用されてもいい。Ｒ２の基中の水素原子がフッ素原子で置換された化合物である場合、本願発明の重合体をレジスト用樹脂の原料として使用した場合、レジスト用樹脂の透明性が向上することが期待され、好ましい。
【００２２】
本発明で使用される一般式（３）中のＲ３は、アリール基、アリールオキシ基、アルコキシ基又はアルコキシアルコキシ基であり、基中の１つ以上の水素原子がハロゲン原子で置換されていてもよい基を表す。更に詳しくは、炭素数６〜２６のアリール基、アリールオキシ基、炭素数１〜３０の直鎖状、分岐状又は環状構造を有してもよいアルコキシ基、アルコキシアルキル基であり、基中の１つ以上の水素原子がハロゲン原子で置換されていてもよい化合物を用いることができる。アリール基はアルキル基、アルコキシ基等の置換基を有していてもよく、また、アルコキシアルキル基としては、テトラヒドロピラニルの様な環中に酸素原子を有する化合物も含む。
【００２３】
本発明で使用される一般式（３）で表される化合物としては、１−クロロ−１−エトキシエタン、１−ブロモ−１−エトキシエタン、１−ヨード−１−エトキシエタン、１−クロロ−１−ブトキシエタン、１−ブロモ−１−ブトキシエタン、１−ヨード−１−ブトキシエタン、（１−クロロエチル）ベンゼン、（１−ブロモエチル）ベンゼン、（１−ヨードエチル）ベンゼン、１−（４−メトキシフェニル）エチルクロライド、１−（４−メトキシフェニル）エチルブロマイド、１−（４−メトキシフェニル）エチルアイオダイド等を挙げることができ、この中で比較的温和な条件で重合できることから、（１−クロロエチル）ベンゼン、（１−ブロモエチル）ベンゼン、（１−ヨードエチル）ベンゼンが好ましい。一般式（３）で表される化合物の添加量には特に制限はなく、目的とする共重合体の分子量により適宜決定される。
【００２４】
ルイス酸性を有するハロゲン化金属としては、四塩化スズ、四臭化スズ、二塩化スズ、二臭化スズ、二塩化亜鉛、二臭化亜鉛、二沃化亜鉛、三塩化アルミニウム、三臭化アルミニウム、三塩化鉄、四塩化チタン、四臭化チタン等を挙げることができ、狭分散性の重合体が得られることから好ましくは、四塩化スズ、四臭化スズ、二塩化亜鉛、二臭化亜鉛、二沃化亜鉛である。ルイス酸性を有するハロゲン化金属の添加量は、一般式（３）で表される化合物の０．１〜１０倍モルが好ましい。
【００２５】
本発明における重合反応は、バルクで行ってもよいが、通常、溶液重合法が採用される。溶液重合において使用される溶媒としては、ベンゼン、トルエン、ｎ−ヘキサン、シクロヘキサン、四塩化炭素、塩化メチレン等の不活性溶媒を挙げることができる。これらは単独或いは併用して使用される。溶液重合を行うに当たっては、反応容器に溶媒を投入した後、一般式（４）及び一般式（５）で表される単量体、一般式（３）で表される化合物を順次添加し、最後にルイス酸性を有するハロゲン化金属を添加して行う。また、重合温度は−８０℃〜８０℃の範囲で実施することが好ましく、更に好ましくは、温和な条件である−２０〜５０℃の範囲である。重合時間は１分〜２４時間の範囲で実施するのが好ましい。１分未満では、重合の制御が困難となり、一方２４時間を越えると、生産性の低下に繋がる。
【００２６】
本発明で得られる狭分散性オキシスチレン共重合体は、一般式（１）で表されるオキシスチレン系繰り返し単位及び一般式（２）で表されるビニルエーテル系繰り返し単位の各々１種または２種以上からなる。一般式（１）と一般式（２）の組成比（モル比）は特に制限されないが、９９：１〜５０：５０のものが好ましい。
【化４】

（式中、Ｒ１は、ｔ−ブチル基、１−エトキシエチル基を表す。）
【化５】

（式中、Ｒ２は、アルキル基、アリール基、アリールアルキル基又はアルコキシアルキル基であり、基中の１つ以上の水素原子がフッ素原子で置換されていてもよい基を表す。）
【００２７】
また、重合体の分子量（Ｍｎ）は通常１０００〜１０００００であり、好ましくは３０００〜５００００である。Ｍｎが１０００未満であると、重合体の耐熱性が低下する傾向があり、一方１０００００を越えると、重合体の溶解性が低下する傾向がある。重合体の分散度（Ｍｗ／Ｍｎ）は、１．０〜１．５である。
【００２８】
【実施例】
以下に、本発明の方法を実施例により具体的に説明するが、本発明はこれら実施例のみに限定されるものではない。
【００２９】
尚、以下の実施例中、重合率は、重合溶液中の残存モノマーをガスクロマトグラフィーにより測定することにより求めた。又、重合体の重量平均分子量Ｍｗ及び数平均分子量Ｍｎは、ゲルパーミエーションクロマトグラフィー（ＧＰＣ）により測定した。
【００３０】
実施例１
乾燥したガラス製反応容器を乾燥窒素ガスで十分に置換した。この反応容器に溶媒として１５ｇのトルエンを投入し、続いてｐ−ｔ−ブトキシスチレン５．９６ｇ（３３．８ミリモル）、ｎ−ブチルビニルエーテル０．３７ｇ（３．７ミリモル）、（１−ブロモエチル）ベンゼンの１０重量％トルエン溶液２．３１ｇ（１．３１ミリモル）を順次添加した。この混合液を攪拌しながら系内の温度を３０℃にした後、二沃化亜鉛の３０重量％テトラヒドロフラン溶液１．２５ｍｌ（１．６９ミリモル）を添加して重合を開始させた。１５時間重合を継続した時点で、２，６−ジ−ｔ−ブチル−４−メチルピリジンを含むメタノールを反応系内に添加して重合を停止させた。この時点での重合率は９９．３％であった。得られた重合溶液は１０重量％チオ硫酸ナトリウム水溶液で洗浄し、次いで、１０重量％水酸化ナトリウム水溶液で洗浄した。その後、大量のメタノールに投入し、重合物を析出させ、重合体を得た。
【００３１】
ＧＰＣ及びＨ−ＮＭＲ測定の結果、得られた重合体は、Ｍｎ＝１０７００、Ｍｗ／Ｍｎ＝１．３０のポリ［ｐ−ｔ−ブトキシスチレン／ｎ−ブチルビニルエーテル］共重合体であり、ｐ−ｔ−ブトキシスチレン単位とｎ−ブチルビニルエーテル単位の組成比（モル比）は９２／８であった。
【００３２】
実施例２
（１−ブロモエチル）ベンゼンに替えて、１−ブロモ−１−エトキシエタンの１０重量％トルエン溶液２．０ｇ（１．３１ミリモル）を用い、重合温度を−１５℃にした以外は実施例１と同様の操作で重合を行った。この場合の重合率は９８．３％であった。
【００３３】
ＧＰＣ及びＨ−ＮＭＲ測定の結果、得られた重合体は、Ｍｎ＝９７００、Ｍｗ／Ｍｎ＝１．４１のポリ［ｐ−ｔ−ブトキシスチレン／ｎ−ブチルビニルエーテル］共重合体であり、ｐ−ｔ−ブトキシスチレン単位とｎ−ブチルビニルエーテル単位の組成比（モル比）は８８／１２であった。
【００３４】
実施例３
（１−ブロモエチル）ベンゼンに替えて、１−（４−メトキシフェニル）エチルブロマイドの１０重量トルエン溶液２．８２ｇ（１．３１ミリモル）を用い、重合温度を−１５℃にした以外は実施例１と同様の操作で重合を行った。この場合の重合率は９７．９％であった。
【００３５】
ＧＰＣ及びＨ−ＮＭＲ測定の結果、得られた重合体は、Ｍｎ＝１２７００、Ｍｗ／Ｍｎ＝１．４４のポリ［ｐ−ｔ−ブトキシスチレン／ｎ−ブチルビニルエーテル］共重合体であり、ｐ−ｔ−ブトキシスチレン単位とｎ−ブチルビニルエーテル単位の組成比（モル比）は８５／１５であった。
【００３６】
実施例４
乾燥したガラス製反応容器を乾燥窒素ガスで十分に置換した。この反応容器に溶媒として１５ｇのトルエンを投入し、続いてｐ−（１−エトキシエトキシ）スチレン６．５ｇ（３３．８ミリモル）、ｎ−ブチルビニルエーテル０．３７ｇ（３．７ミリモル）、（１−ブロモエチル）ベンゼンの１０重量％トルエン溶液２．３ｇ（１．２５ミリモル）を順次添加した。この混合液を攪拌しながら系内の温度を３０℃にした後、二沃化亜鉛の３０重量％テトラヒドロフラン溶液１．２５ｍｌ（１．６９ミリモル）を添加して重合を開始させた。１５時間重合を継続した時点で、２，６−ジ−ｔ−ブチル−４−メチルピリジンを含むメタノールを反応系内に添加して重合を停止させた。この時点での重合率は９９．１％であった。得られた重合溶液は１０重量％チオ硫酸ナトリウム水溶液で洗浄し、次いで、１０重量％水酸化ナトリウム水溶液で洗浄した。その後、大量のメタノールに投入し、重合物を析出させ、重合体を得た。
【００３７】
ＧＰＣ及びＨ−ＮＭＲ測定の結果、得られた重合体は、Ｍｎ＝９５００、Ｍｗ／Ｍｎ＝１．３２のポリ［ｐ−（１−エトキシエトキシ）スチレン／ｎ−ブチルビニルエーテル］共重合体であり、ｐ−（１−エトキシエトキシ）スチレン単位とｎ−ブチルビニルエーテル単位の組成比（モル比）は９１／９であった。
実施例５
乾燥したガラス製反応容器を乾燥窒素ガスで十分に置換した。この反応容器に溶媒として１５ｇのトルエンを投入し、続いてｐ−（１−エトキシエトキシ）スチレン５．１９ｇ（２７ミリモル）、ｐ−ｔ−ブトキシスチレン１．１９ｇ（６．７５ミリモル）、ｎ−ブチルビニルエーテル０．３７ｇ（３．７ミリモル）、（１−ブロモエチル）ベンゼンの１０重量％トルエン溶液２．３１ｇ（１．２５ミリモル）を順次添加した。この混合液を攪拌しながら系内の温度を３０℃にした後、二沃化亜鉛の３０重量％テトラヒドロフラン溶液１．２５ｍｌ（１．６９ミリモル）を添加して重合を開始させた。１５時間重合を継続した時点で、２，６−ジ−ｔ−ブチル−４−メチルピリジンを含むメタノールを反応系内に添加して重合を停止させた。この時点での重合率は９９．１％であった。得られた重合溶液は１０重量％チオ硫酸ナトリウム水溶液で洗浄し、次いで、１０重量％水酸化ナトリウム水溶液で洗浄した。その後、大量のメタノールに投入し、重合物を析出させ、重合体を得た。
【００３８】
ＧＰＣ及びＨ−ＮＭＲ測定の結果、得られた重合体は、Ｍｎ＝６８００、Ｍｗ／Ｍｎ＝１．３３のポリ［ｐ−（１−エトキシエトキシ）スチレン／ｐ−ｔ−ブトキシスチレン／ｎ−ブチルビニルエーテル］共重合体であり、ｐ−（１−エトキシエトキシ）スチレン単位、ｐ−ｔ−ブトキシスチレン単位及びｎ−ブチルビニルエーテル単位の組成比（モル比）は７４／１７／９であった。
【００３９】
比較例１
乾燥したガラス製反応容器を乾燥窒素ガスで十分に置換した。この反応容器に溶媒として１５ｇのトルエンを投入し、続いてｐ−（１−エトキシエトキシ）スチレン６．５ｇ（３３．８ミリモル）、ｎ−ブチルビニルエーテル０．３７ｇ（３．７ミリモル）、アゾビスイソブチロニトリル０．０５４ｇ（０．３４ミリモル）を添加した。この混合液を攪拌しながら系内の温度を８０℃にして重合（ラジカル重合）を開始させた。１８時間重合を継続した時点でハイドロキノンを少量添加して重合を停止させた。この時点の重合率は６９％であった。重合溶液を大量のメタノールに投入し、重合物を析出させ、重合体を得た。
【００４０】
ＧＰＣ及びＨ−ＮＭＲ測定の結果、得られた重合体は、Ｍｎ＝７４００、Ｍｗ／Ｍｎ＝２．２５のポリ（ｐ−（１−エトキシエトキシ）スチレン）単独重合体であり、目的とする共重合体は得られなかった。
【００４１】
比較例２
乾燥したガラス製反応容器を乾燥窒素ガスで十分に置換した。この反応容器に溶媒として１５ｇのトルエンを投入し、続いてｐ−ｔ−ブトキシスチレン５．９６ｇ（３３．８ミリモル）、ｎ−ブチルビニルエーテル０．３７ｇ（３．７ミリモル）、アゾビスイソブチロニトリル０．０５４ｇ（０．３４ミリモル）を添加した。この混合液を攪拌しながら系内の温度を８０℃にして重合を開始させた。１８時間重合を継続した時点でハイドロキノンを少量添加して重合を停止させた。この時点の重合率は６５％であった。重合溶液を大量のメタノールに投入し、重合物を析出させ、重合体を得た。
【００４２】
ＧＰＣ及びＨ−ＮＭＲ測定の結果、得られた重合体は、Ｍｎ＝５３００、Ｍｗ／Ｍｎ＝２．１１のポリ（ｐ−ｔ−ブトキシスチレン）単独重合体であり、目的とする共重合体は得られなかった。
【００４３】
【発明の効果】
以上の説明から明らかなように、従来の方法では得ることができなかった狭分散性オキシスチレン系共重合体及びその製造方法を提供することが可能となった。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a narrowly dispersible oxystyrene copolymer useful as a raw material for a resin component for resist and a method for producing the same.
[0002]
[Prior art]
Oxystyrene-based polymers are used as functional polymer materials in various industrial fields. In particular, it is an indispensable material as a raw material for resist resin components in the field of electronic materials, particularly in the manufacture of ultra-highly integrated semiconductor circuits. In this field, high resolution is constantly demanded, and improvement of resist resins is actively studied. In order to increase the resolution, the molecular weight distribution of the resin used is narrowed, that is, the degree of dispersion (Mw / Mn), which is the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn), is reduced, and the narrow dispersibility It is known to be effective.
[0003]
In addition, it is known that it is effective to copolymerize an oxystyrene monomer and a copolymerizable monomer in order to adjust physical properties such as solubility of the resist resin.
[0004]
Conventionally, as a method for producing an oxystyrene polymer, a method by radical polymerization or a method by anion polymerization is known.
[0005]
Although the method by radical polymerization is simple in polymerization, it has a problem that it is difficult to obtain a narrowly dispersible copolymer because the molecular weight distribution cannot be controlled.
[0006]
On the other hand, as a method for obtaining a narrowly dispersible polymer by anionic polymerization, for example, a method by living anionic polymerization as described in JP-A-59-199705 and JP-A-6-32835 is known. ing. However, in this method, a slight amount of impurities in the polymerization system also becomes a problem. In the case of moisture, polymerization does not proceed unless it is completely removed, and a dangerous initiator such as an organometallic compound is required. The polymerization conditions are severe. Furthermore, the polymerization temperature needs to be extremely low. Therefore, in order to perform industrial production, special equipment is required, resulting in a problem that the manufacturing cost increases.
[0007]
In addition, when an oxystyrene copolymer is synthesized by a method using radical polymerization or a method using anion polymerization, the copolymerizable monomers that can be used are limited to monomers capable of radical polymerization or anion polymerization. Therefore, it has been difficult to copolymerize a cationic polymerizable monomer such as a vinyl ether monomer. Therefore, a narrowly dispersible oxystyrene copolymer obtained by copolymerizing an oxystyrene monomer and a vinyl ether monomer has not been obtained.
[0008]
[Problems to be solved by the invention]
The present invention has been made in view of the above problems, and an object thereof is to provide a narrowly dispersible oxystyrene copolymer that could not be obtained by a conventional method and a method for producing the same.
[0009]
[Means for Solving the Problems]
As a result of intensive studies to achieve the above object, the present inventors have completed the present invention.
[0010]
That is, the present invention, the following general formula ( 3 )
[0014]
[Chemical 3]

(In the formula, X is a halogen atom, R3 is an aryl group, aryloxy group, alkoxy group or alkoxyalkoxy group which may have a substituent, and one or more hydrogen atoms in the group are halogen atoms. And a halogenated metal having Lewis acidity as an initiator, pt-butoxystyrene, mt-butoxystyrene, p- (1 -Ethoxyethoxy) styrene or oxystyrene monomer selected from m- (1-ethoxyethoxy) styrene and the following general formula (5)
[0016]
[Chemical Formula 10]

(Wherein R5 represents an alkyl group, an aryl group, an arylalkyl group or an alkoxyalkyl group). A method for producing a narrowly dispersible oxystyrene copolymer in which a vinyl ether monomer represented by is there.
[0017]
The present invention will be described in detail below.
[0019]
Examples of the compound represented by the general formula (4), p-t-butoxystyrene, m-t-butoxystyrene, p-(1-ethoxyethoxy) styrene, m-(1-ethoxyethoxy) styrene. These may be used alone or in combination.
[0020]
R5 in the general formula (5) used in the present invention is an alkyl group, an aryl group, an arylalkyl group or an alkoxyalkyl group, and one or more hydrogen atoms in the group may be substituted with a fluorine atom. Represents a good group. More specifically, an alkyl group which may have a linear, branched or cyclic structure having 1 to 20 carbon atoms, an aryl group having 6 to 26 carbon atoms, an arylalkyl group having 7 to 27 carbon atoms, or 1 carbon atom. An alkoxyalkyl group having an alkoxy group which may have a linear, branched or cyclic structure of ˜30, wherein one or more hydrogen atoms in the group may be substituted with fluorine atoms Can be used. The aryl group may have a substituent such as an alkyl group or an alkoxy group, and the alkoxyalkyl group includes a compound having an oxygen atom in a ring such as tetrahydropyranyl.
[0021]
Examples of the compound represented by the general formula (5) include methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, i-propyl vinyl ether, n-butyl vinyl ether, i-butyl vinyl ether, n-amyl vinyl ether, i-amyl vinyl ether, 2 -Ethylhexyl vinyl ether, cyclohexyl vinyl ether, 1-adamantyl vinyl ether, 2-adamantyl vinyl ether, trifluoromethyl vinyl ether, pentafluoroethyl vinyl ether, 2,2,2-trifluoroethyl vinyl ether, phenyl vinyl ether, 4-methylphenyl vinyl ether, 4-tri Fluoromethylphenyl vinyl ether, 4-fluorophenyl vinyl ether, benzyl vinyl ether, 4-fluoroben Vinyl ether, 2-methoxyethyl vinyl ether, 2-ethoxyethyl vinyl ether, and 2-tetrahydropyranyl ether and the like. These may be used alone or in combination. When the hydrogen atom in the R2 group is a compound substituted with a fluorine atom, it is expected that the transparency of the resist resin is expected to improve when the polymer of the present invention is used as a raw material for the resist resin. .
[0022]
R3 in the general formula (3) used in the present invention is an aryl group, an aryloxy group, an alkoxy group or an alkoxyalkoxy group, and one or more hydrogen atoms in the group may be substituted with a halogen atom. Represents a good group. More specifically, an aryl group having 6 to 26 carbon atoms, an aryloxy group, an alkoxy group having 1 to 30 carbon atoms, which may have a linear, branched or cyclic structure, and an alkoxyalkyl group, A compound in which one or more hydrogen atoms may be substituted with a halogen atom can be used. The aryl group may have a substituent such as an alkyl group or an alkoxy group, and the alkoxyalkyl group includes a compound having an oxygen atom in a ring such as tetrahydropyranyl.
[0023]
Examples of the compound represented by the general formula (3) used in the present invention include 1-chloro-1-ethoxyethane, 1-bromo-1-ethoxyethane, 1-iodo-1-ethoxyethane, 1-chloro- 1-butoxyethane, 1-bromo-1-butoxyethane, 1-iodo-1-butoxyethane, (1-chloroethyl) benzene, (1-bromoethyl) benzene, (1-iodoethyl) benzene, 1- (4-methoxy Phenyl) ethyl chloride, 1- (4-methoxyphenyl) ethyl bromide, 1- (4-methoxyphenyl) ethyl iodide and the like. Among them, since polymerization can be performed under relatively mild conditions, (1- Chloroethyl) benzene, (1-bromoethyl) benzene, and (1-iodoethyl) benzene are preferred. There is no restriction | limiting in particular in the addition amount of the compound represented by General formula (3), According to the molecular weight of the target copolymer, it determines suitably.
[0024]
Examples of the metal halide having Lewis acidity are tin tetrachloride, tin tetrabromide, tin dichloride, tin dibromide, zinc dichloride, zinc dibromide, zinc diiodide, aluminum trichloride, aluminum tribromide. , Iron trichloride, titanium tetrachloride, titanium tetrabromide, etc., and preferably from a narrow dispersible polymer, tin tetrachloride, tin tetrabromide, zinc dichloride, dibromide Zinc and zinc diiodide. The addition amount of the metal halide having Lewis acidity is preferably 0.1 to 10 times by mole of the compound represented by the general formula (3).
[0025]
The polymerization reaction in the present invention may be carried out in bulk, but usually a solution polymerization method is employed. Examples of the solvent used in the solution polymerization include inert solvents such as benzene, toluene, n-hexane, cyclohexane, carbon tetrachloride, and methylene chloride. These are used alone or in combination. In performing the solution polymerization, after adding the solvent to the reaction vessel, the monomer represented by the general formula (4) and the general formula (5), the compound represented by the general formula (3) are sequentially added, Finally, a metal halide having Lewis acidity is added. Moreover, it is preferable to implement superposition | polymerization temperature in the range of -80 degreeC-80 degreeC, More preferably, it is the range of -20-50 degreeC which is mild conditions. The polymerization time is preferably 1 minute to 24 hours. If it is less than 1 minute, it becomes difficult to control the polymerization, while if it exceeds 24 hours, it leads to a decrease in productivity.
[0026]
The narrowly dispersible oxystyrene copolymer obtained in the present invention is one or two of each of an oxystyrene-based repeating unit represented by the general formula (1) and a vinyl ether-based repeating unit represented by the general formula (2). Consists of the above. The composition ratio (molar ratio) between general formula (1) and general formula (2) is not particularly limited, but is preferably 99: 1 to 50:50.
[Formula 4]

(In the formula, R1 represents a t-butyl group or a 1-ethoxyethyl group.)
[Chemical formula 5]

(In the formula, R2 represents an alkyl group, an aryl group, an arylalkyl group, or an alkoxyalkyl group, and represents a group in which one or more hydrogen atoms in the group may be substituted with a fluorine atom.)
[0027]
Moreover, the molecular weight (Mn) of a polymer is 1000-100000 normally, Preferably it is 3000-50000. If Mn is less than 1000, the heat resistance of the polymer tends to decrease, whereas if it exceeds 100,000, the solubility of the polymer tends to decrease. The degree of dispersion (Mw / Mn) of the polymer is 1.0 to 1.5.
[0028]
【Example】
EXAMPLES The method of the present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.
[0029]
In the following examples, the polymerization rate was determined by measuring the residual monomer in the polymerization solution by gas chromatography. Moreover, the weight average molecular weight Mw and the number average molecular weight Mn of the polymer were measured by gel permeation chromatography (GPC).
[0030]
Example 1
The dried glass reaction vessel was thoroughly replaced with dry nitrogen gas. Into this reaction vessel, 15 g of toluene was charged as a solvent, followed by 5.96 g (33.8 mmol) of pt-butoxystyrene, 0.37 g (3.7 mmol) of n-butyl vinyl ether, (1-bromoethyl) 2.31 g (1.31 mmol) of a 10 wt% toluene solution of benzene was added sequentially. The temperature of the system was raised to 30 ° C. while stirring the mixture, and then 1.25 ml (1.69 mmol) of a 30 wt% solution of zinc diiodide in tetrahydrofuran was added to initiate polymerization. When the polymerization was continued for 15 hours, methanol containing 2,6-di-t-butyl-4-methylpyridine was added to the reaction system to stop the polymerization. The polymerization rate at this time was 99.3%. The resulting polymerization solution was washed with a 10 wt% aqueous sodium thiosulfate solution and then washed with a 10 wt% aqueous sodium hydroxide solution. Then, it poured into a large amount of methanol, the polymer was deposited, and the polymer was obtained.
[0031]
As a result of GPC and H-NMR measurement, the obtained polymer was a poly [pt-butoxystyrene / n-butyl vinyl ether] copolymer having Mn = 10700 and Mw / Mn = 1.30, p- The composition ratio (molar ratio) of the t-butoxystyrene unit and the n-butyl vinyl ether unit was 92/8.
[0032]
Example 2
Example 1 except that 2.0 g (1.31 mmol) of a 10 wt% toluene solution of 1-bromo-1-ethoxyethane was used instead of (1-bromoethyl) benzene, and the polymerization temperature was −15 ° C. Polymerization was performed in the same manner. The polymerization rate in this case was 98.3%.
[0033]
As a result of GPC and H-NMR measurement, the obtained polymer was a poly [pt-butoxystyrene / n-butyl vinyl ether] copolymer having Mn = 9700 and Mw / Mn = 1.41. The composition ratio (molar ratio) between the t-butoxystyrene unit and the n-butyl vinyl ether unit was 88/12.
[0034]
Example 3
Example 1 except that instead of (1-bromoethyl) benzene, 2.82 g (1.31 mmol) of a 10 weight toluene solution of 1- (4-methoxyphenyl) ethyl bromide was used and the polymerization temperature was set to −15 ° C. Polymerization was carried out in the same manner as described above. The polymerization rate in this case was 97.9%.
[0035]
As a result of GPC and H-NMR measurement, the obtained polymer was a poly [pt-butoxystyrene / n-butyl vinyl ether] copolymer having Mn = 12,700 and Mw / Mn = 1.44, p- The composition ratio (molar ratio) of the t-butoxystyrene unit and the n-butyl vinyl ether unit was 85/15.
[0036]
Example 4
The dried glass reaction vessel was thoroughly replaced with dry nitrogen gas. Into this reaction vessel, 15 g of toluene was added as a solvent, followed by 6.5 g (33.8 mmol) of p- (1-ethoxyethoxy) styrene, 0.37 g (3.7 mmol) of n-butyl vinyl ether, (1 -Bromoethyl) 2.3 g (1.25 mmol) of a 10 wt% toluene solution in benzene was added sequentially. The temperature of the system was raised to 30 ° C. while stirring the mixture, and then 1.25 ml (1.69 mmol) of a 30 wt% solution of zinc diiodide in tetrahydrofuran was added to initiate polymerization. When the polymerization was continued for 15 hours, methanol containing 2,6-di-t-butyl-4-methylpyridine was added to the reaction system to stop the polymerization. The polymerization rate at this point was 99.1%. The resulting polymerization solution was washed with a 10 wt% aqueous sodium thiosulfate solution and then washed with a 10 wt% aqueous sodium hydroxide solution. Then, it poured into a large amount of methanol, the polymer was deposited, and the polymer was obtained.
[0037]
As a result of GPC and H-NMR measurement, the obtained polymer was a poly [p- (1-ethoxyethoxy) styrene / n-butyl vinyl ether] copolymer having Mn = 9500 and Mw / Mn = 1.32. The composition ratio (molar ratio) of p- (1-ethoxyethoxy) styrene unit and n-butyl vinyl ether unit was 91/9.
Example 5
The dried glass reaction vessel was thoroughly replaced with dry nitrogen gas. The reaction vessel was charged with 15 g of toluene as a solvent, followed by 5.19 g (27 mmol) of p- (1-ethoxyethoxy) styrene, 1.19 g (6.75 mmol) of pt-butoxystyrene, n- 0.37 g (3.7 mmol) of butyl vinyl ether and 2.31 g (1.25 mmol) of a 10 wt% toluene solution of (1-bromoethyl) benzene were sequentially added. The temperature of the system was raised to 30 ° C. while stirring the mixture, and then 1.25 ml (1.69 mmol) of a 30 wt% solution of zinc diiodide in tetrahydrofuran was added to initiate polymerization. When the polymerization was continued for 15 hours, methanol containing 2,6-di-t-butyl-4-methylpyridine was added to the reaction system to stop the polymerization. The polymerization rate at this point was 99.1%. The resulting polymerization solution was washed with a 10 wt% aqueous sodium thiosulfate solution and then washed with a 10 wt% aqueous sodium hydroxide solution. Then, it poured into a large amount of methanol, the polymer was deposited, and the polymer was obtained.
[0038]
As a result of GPC and H-NMR measurement, the obtained polymer was poly [p- (1-ethoxyethoxy) styrene / pt-butoxystyrene / n-butyl with Mn = 6800 and Mw / Mn = 1.33. Vinyl ether] copolymer, and the composition ratio (molar ratio) of p- (1-ethoxyethoxy) styrene unit, pt-butoxystyrene unit and n-butyl vinyl ether unit was 74/17/9.
[0039]
Comparative Example 1
The dried glass reaction vessel was thoroughly replaced with dry nitrogen gas. Into this reaction vessel, 15 g of toluene was added as a solvent, followed by 6.5 g (33.8 mmol) of p- (1-ethoxyethoxy) styrene, 0.37 g (3.7 mmol) of n-butyl vinyl ether, azobis 0.054 g (0.34 mmol) of isobutyronitrile was added. While stirring this mixed solution, the temperature in the system was raised to 80 ° C. to initiate polymerization (radical polymerization). When the polymerization was continued for 18 hours, a small amount of hydroquinone was added to terminate the polymerization. The polymerization rate at this time was 69%. The polymerization solution was put into a large amount of methanol to precipitate a polymer, and a polymer was obtained.
[0040]
As a result of GPC and H-NMR measurement, the obtained polymer was a poly (p- (1-ethoxyethoxy) styrene) homopolymer having Mn = 7400 and Mw / Mn = 2.25, and the desired copolymer was obtained. A polymer was not obtained.
[0041]
Comparative Example 2
The dried glass reaction vessel was thoroughly replaced with dry nitrogen gas. Into this reaction vessel, 15 g of toluene was charged as a solvent, followed by 5.96 g (33.8 mmol) of pt-butoxystyrene, 0.37 g (3.7 mmol) of n-butyl vinyl ether, azobisisobutyro 0.054 g (0.34 mmol) of nitrile was added. While stirring this mixed solution, the temperature in the system was raised to 80 ° C. to initiate polymerization. When the polymerization was continued for 18 hours, a small amount of hydroquinone was added to terminate the polymerization. The polymerization rate at this time was 65%. The polymerization solution was put into a large amount of methanol to precipitate a polymer, and a polymer was obtained.
[0042]
As a result of GPC and H-NMR measurement, the resulting polymer is a poly (pt-butoxystyrene) homopolymer with Mn = 5300 and Mw / Mn = 2.11. It was not obtained.
[0043]
【The invention's effect】
As is clear from the above description, it has become possible to provide a narrowly dispersible oxystyrene copolymer that could not be obtained by a conventional method and a method for producing the same.

Claims (2)

The following general formula (3)

Wherein X is a halogen atom, R3 is an aryl group, aryloxy group, alkoxy group or alkoxyalkoxy group which may have a substituent, and one or more hydrogen atoms in the group are halogen atoms. Represents a group which may be substituted.) And a halogenated metal halide having Lewis acidity as an initiator, pt-butoxystyrene, mt-butoxystyrene, p- (1- An oxystyrene monomer selected from ethoxyethoxy) styrene or m- (1-ethoxyethoxy) styrene, and the following general formula (5):

(Wherein R5 represents an alkyl group, an aryl group, an arylalkyl group or an alkoxyalkyl group, and represents a group in which one or more hydrogen atoms in the group may be substituted with a fluorine atom). A method for producing a narrowly dispersible oxystyrene copolymer comprising copolymerizing a vinyl ether monomer. The production method according to claim 1, wherein the compound represented by the general formula (3) is (1-chloroethyl) benzene, (1-bromoethyl) benzene or (1-iodoethyl) benzene.