JP2004250630A - Process for producing hydrophobic liquid droplet, process and apparatus for producing polymer bead and process for producing ion exchange resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a process for stably producing a polymer bead of high uniformity in particle size on an industrial scale by means of simple equipment without need of the strict control of flow rate of liquids and without accompanying the generation of heat, problems in the aspect of safety or the like while theoretically preventing the development of liquid droplets having a large particle size by uniting the liquids together. <P>SOLUTION: The process for producing the polymer bead comprises introducing a hydrophobic liquid containing polymerizable monomers and a hydrophilic liquid respectively through separate liquid inlet passages and permitting the hydrophobic liquid and the hydrophilic liquid to join and mix with each other within a channel structure wherein a plurality of liquid inlet passages join and lead into one liquid outlet passage, discharging the resultant mixed liquid through the liquid outlet passage into an aqueous medium and dispersing the hydrophobic liquid contained in the mixed liquid into the aqueous medium to thereby produce liquid droplets comprising the hydrophobic liquid and further polymerizing the polymerizable monomers contained in the liquid droplets. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【００５１】
更に、上記式中の相当直径は、以下の式で定義される。
【数２】

【００５２】
これらの流速は、使用する疎水性液体及び親水性液体の種類や流路部２０の流路構造の形状、使用する水性媒質の種類、目標とする粒径などに応じて、適切な値を適宜選択するのが好ましい。また、疎水性液体と親水性液体との流速の比は特に制限されないが、水性媒質中に放出される疎水性液体の量を一定に揃える観点からは、実質的に同程度の流速であることが好ましく、具体的には疎水性液体の流速に対する親水性液体の流速の比率が、通常０．５以上、中でも０．８以上、また、通常２以下、中でも１．２以下の範囲が好ましい。
【００５３】
以上の条件下で、疎水性液体及び親水性液体をそれぞれ対応する流入路Ａ，Ｂから導入すると、これらの疎水性液体と親水性液体は流路構造中で合流し、混合液を形成する。この混合液中において、疎水性液体と親水性液体とは互いに混和するのではなく、非混和の状態を保ちながら一定量ずつ交互に配置して流出路Ｃを通過し、最終的には流出路Ｃの出口から交互に水性媒質中に放出される。ここで、親水性液体は放出と同時に水性媒質に混和してしまうため、結果として一定量の疎水性液体が断続的に水性媒質中に放出されて分散することになる。よって、液の合一による大粒径の液滴の発生を原理的に防ぎながら、均一な粒径の液滴を生成することが可能となるのである。
【００５４】
上記の液滴生成工程によって得られた疎水性液滴は、続いて重合反応槽６０に導入され、重合反応工程に供される。重合反応工程では、重合反応槽６０中の疎水性液滴に適切な重合反応条件を付加し、疎水性液滴の粒径の均一性を維持しながら液滴中のエチレン性モノマーを重合させることにより、これをポリマービーズに転換する。
【００５５】
重合反応の開始条件は、疎水性液滴中に含まれる重合開始剤の種類に応じて適宜選択すればよいが、ラジカル重合開始剤の場合、加熱や光照射等によりラジカル発生を促すことによって、重合反応を開始させる。熱ラジカル重合開始剤を使用する場合、加える温度は重合開始剤の種類によって異なるが、通常３０℃以上、好ましくは６０℃以上、また、通常１５０℃以下、好ましくは１００℃以下の範囲である。また、重合時の圧力は、上記の各種条件や重合温度等によって異なるが、通常は常圧又は加圧条件下で行なう。加圧条件の場合、通常は１ＭＰａ以下の範囲が好適である。
【００５６】
重合反応の時間は、疎水性液滴に含まれる重合性モノマーの組成により異なるが、通常６時間以上、１０時間以下の範囲である。重合反応が長時間にわたるため、疎水性液滴の合着や破砕を抑制して粒径の均一性を維持し、且つ、疎水性液滴の分散状態を均一に保つために、撹絆を与えることが必要である。攪拌条件は、重合反応槽６０の内径や攪拌手段６２の形状、疎水性液滴に含まれる重合性モノマーの物性、疎水性液滴の粒径等に応じて異なるが、粒径の均一性を保持する最適条件として一義的に決定することが可能である。具体的な攪拌条件としては、例えば、上述の特許文献４及び特許文献５の記載を参照できる。
【００５７】
重合反応の終了後、得られた固体状態のポリマービーズを、濾過等の公知の脱水技術や固液分離技術によって水性媒質から分離して回収する。
【００５８】
得られたポリマービーズ中には、未重合の重合性モノマーや、有機溶媒、高分子物質、界面活性剤、塩等が残留する。よって、水や有機溶媒等の溶剤を用いて洗浄することにより、これらの残留成分を取り除くことが好ましい。有機溶媒としては、メタノール、エタノール、イソプロピルアルコール、アセトン、メチルイソブチルケトン（ＭＩＢＫ）、メチル−ｔ−ブチルエーテル（ＭＴＢＥ）、トルエン、クロロベンゼン、ニ塩化エチレン、ジクロロメタン、クロロホルム等が挙げられる。洗浄の際の溶剤の使用量は、重合性モノマーの種類や重合反応の条件等によって異なるが、通常１倍量以上、好ましくは２倍量以上、また、通常１００倍量以下、好ましくは１０倍量以下の範囲である。洗浄時には反応生成物を加熱することによって、洗浄の効率を高めることが可能である。この場合、洗浄に用いられる溶剤の沸点以下の温度に加熱しながら洗浄を行なうことが好ましい。また、水を溶剤として用いる場合には、水や温水の他、水蒸気を通気しながら洗浄することも可能である。
【００５９】
得られたポリマービーズには、その目的に応じて様々な処理を施すことができる。例えば、ポリマービーズをイオン交換樹脂として使用する場合には、得られたポリマービーズ中に目的とするイオン交換基を導入する処理を行なう。ポリマービーズ中にイオン交換基を導入する手法としては種々のものが知られており、重合性モノマーの種類や導入するイオン交換基の種類、導入量等に応じて適宜選択すれば良い。
【００６０】
本発明の製造方法において得られる疎水性液滴及びポリマービーズの粒径は、顕微鏡写真に基づいて測定することができる。疎水性液滴の平均粒径は、特に制限されないが、通常１０μｍ以上、好ましくは１００μｍ以上、また、通常２０００μｍ以下、好ましくは１０００μｍ以下の範囲である。また、疎水性液滴を用いて製造されるポリマービーズの平均粒径も、基本的には疎水性液滴の平均粒径とほぼ同一である。
【００６１】
また、疎水性液滴及びポリマービーズの粒径の均一性は、均一係数で評価することができる。均一係数は、例えば、「ダイヤイオン^Ｒ イオン交換樹脂・合成吸着剤マニュアル〔基礎編〕」（三菱化学（株）イオン交換樹脂事業部編、平成７年１月１０日発行、第８版）１３９〜１４１頁記載の方法に従って、液滴又はポリマービーズの粒度分布から以下の式により求めることができる。
【００６２】
【数３】

【００６３】
本実施形態で得られる疎水性液滴の均一係数は、通常１．２以下、好ましくは１．１以下である。また、ポリマービーズの均一係数も、疎水性液滴とほぼ同一の値の範囲をとる。粒径が均一であるとして市販されているイオン交換樹脂の均一係数は、通常１．０２以上、１．２以下の範囲であるから、本実施形態で得られるポリマービーズは、イオン交換樹脂の原料として充分に実用的なレベルの粒径の均一性を有していることが判る。
【００６４】
なお、これらの平均粒径及び均一係数の値は、流路部２０の流路構造の形状、使用する疎水性液体及び親水性液体の種類や流速、使用する水性媒質の種類等の条件を変更することによって、適宜調整することが可能である。
【００６５】
以上、本実施形態のポリマービーズの製造装置及び製造方法によれば、複数の流入路が合流して一の流出路に至る流路構造を用い、疎水性液体と親水性液体とを別々の流入路から導入して合流させることにより、均一な量の疎水性液体を断続的に水性媒質中に放出させているので、液の合一による大粒径液滴の発生を原理的に防ぎつつ、均一な粒径の疎水性液滴を簡便に発生させることが可能となっている。また、疎水性液体を噴出孔から水性媒体中へ連続的に噴出させて疎水性液滴を発生させる従来の方法の様に、流量の厳密な制御を必要とせず、幅広い操作条件の下で確実に均一粒径の疎水性液滴を得ることができる。更に、疎水性液体の噴出時に機械的振動を付与して疎水性液体の噴出流を砕く従来の改良法の様に、熱の発生や安全面の課題等を伴うことなく、簡素な設備により工業的規模で安定的に均一粒径のポリマービーズを製造できる。また、得られるポリマービーズを用いて、これにイオン交換基を導入することにより、均一性の高いイオン交換樹脂を工業的規模で安定的に製造することができる。
【００６６】
なお、本実施形態のポリマービーズの製造装置１０は、流路部２０が、複数の流入路が合流して一の流出路に至る流路構造を一つだけ有する構成を取っていたが、その変形例として、この様な流路構造を複数設ける構成とすることも可能である。図３に、本発明の一実施形態の変形例に係るポリマービーズの製造装置１０’の構成を模式的に示す。図３において図１と同一の符号を付した構成要素は、同一の機能を有するものであるから、説明は省略する。図３に示すように、本変形例の製造装置１０’は、複数の流入路が合流して一の流出路に至る流路構造を複数有する流路部２０’を備えており、疎水性液体送液ポンプ３１及び親水性液体送液ポンプ４１から送液される疎水性液体及び親水性液体は、それぞれ複数の流路構造の流入路へと分岐して導入される様に構成されている。本変形例の構成によれば、複数の流路構造の流出路から同時に多くの疎水性液滴を発生させ、ポリマービーズの生産性を高めることが可能となる。なお、図３では流路部２０が有する流露構造の数は４つであるが、その数は特に制限されず、２以上の任意の数とすることができる。
【００６７】
また、上記の実施形態及び変形例のポリマービーズの製造装置１０の構成のうち、疎水性液滴の製造に関わる構成要素のみを独立させ、均一粒径の疎水性液滴の製造に特化した装置を構成することも可能である。図４に、本発明の一実施形態に係る疎水性液滴の製造装置７０の構成を模式的に示す。なお、図４において図１と同一の符号を付した構成要素は、同一の機能を有するものであるから、説明は省略する。図４に示す様に、本実施形態の疎水性液滴の製造装置７０は、上記の実施形態のポリマービーズの製造装置１０の構成要素のうち、疎水性液滴の製造に関わる構成要素と、基本的に同一の構成要素からなる。また、疎水性液滴製造槽５０’には、製造された疎水性液滴の粒径の均一性を維持するべく疎水性液滴製造槽５０’内の水性媒質を攪拌する疎水性液滴攪拌手段５３が設けられる。この様な構成によって、上記のポリマービーズの製造装置１０と同様、流量の厳密な制御を必要とせず、且つ、熱の発生や安全面の課題等を伴うことなく、液の合一による大粒径の液滴の発生を原理的に防ぎながら、均一性の高い疎水性液滴を、疎水性液滴に特化した簡素な設備により製造することができる。
【００６８】
本製造装置７０により得られた均一粒径の疎水性液滴は、上記の様にポリマービーズの製造原料としても良いが、その他の目的に用いることも可能である。その他の目的としては、晶析（結晶製成）等が挙げられる。この場合、疎水性液滴の成分としては、上に説明した重合性モノマー等の成分に限定されず、その目的に応じて各種の適切な成分を求めればよい。
【００６９】
以上、本発明の実施形態について説明したが、本発明はこれらの実施形態に制限されるものではなく、その趣旨を逸脱しない範囲において、適宜変更して実施することが可能である。
【００７０】
特に、本発明に係るポリマービーズ及び疎水性液滴の製造装置の各構成要素について、それらの外観、形状、結合状態、位置関係等は、上記の実施形態に示したものに制限されず、上に説明した機能を支障なく発揮できる限り、自由に変更することが可能である。例えば、図１，３，４に示した様に、流路部２０を疎水性液滴製造槽５０，５０’の外部に設け、流出路を疎水性液滴製造槽５０，５０’の内部に導入する構成としてもよいが、その変形例として、図５に示すように、流路部２０を疎水性液滴製造槽５０，５０’の外部に設け、流入路のみを疎水性液滴製造槽５０，５０’の外部に延出する様に構成しても良い。なお、図５は、上記の実施形態の変形例に係るポリマービーズの製造装置及び疎水性液滴の製造装置の部分的な構成を模式的に示す図であり、図１及び４と同一の符号を付した構成要素はそれらと同一の機能を有するものである。
【００７１】
【実施例】
以下、本発明を実施例により更に詳細に説明するが、本発明はその要旨を超えない限り以下の実施例に制約されるものではなく、種々変形して実施することが可能である。なお、本明細書の記載において「ＢＶ」とは、Ｂｅｄ Ｖｏｌｕｍｅ（カラム充填樹脂体積に対する体積比）を表わす。
【００７２】
［実施例１］
疎水性液体が流入する管Ａとして内径０．８ｍｍのＳＵＳ配管、親水性液体が流入するする管Ｂとして内径０．８ｍｍのＳＵＳ配管、疎水性液体及び親水性液体の混合液が流出する管Ｃとして内径０．１ｍｍのＳＵＳ配管を用い、これらを内径０．３ｍｍのＳＵＳ製Ｔ字管で接続して、二の流入路（管Ａ及び管Ｂ）が合流して一の流出路（管Ｃ）に至る流路構造を作成した。管Ｃ（流出路）の出口は水性媒質に浸した状態とした。
【００７３】
疎水性液体として、キシダ化学製スチレン８６ｇと、三共化成製５７％ジビニルベンゼン１４ｇと、ナカライテスク製７５％ベンゾイルパーオキサイド０．６７ｇとの混合液を用いた。
親水性液体として、０．５％クラレ製ＰＶＡ溶液を用いた。
水性媒質として、２％クラレ製ＰＶＡ溶液を用いた。
【００７４】
上記の疎水性液体及び親水性液体を、それぞれ管Ａ及び管Ｂの入口から、ともにシリンダーポンプを用いて、流速１５ｍｌ／ｈで同時に送液を開始した。管Ａから導入された疎水性液体と、管Ｂから導入された親水性液体は、流路構造内で合流して混合液となり、管Ｃから水性媒質中に放出されて、疎水性液体からなる液滴（疎水性液滴）が発生した。得られた疎水性液滴の顕微鏡写真を撮影し、その平均粒径及び均一係数を求めたところ、平均粒径は３５０μｍ、均一係数は１．０７となった。
【００７５】
次に、この疎水性液滴を１Ｌの反応フラスコに移し、撹拌下、８０℃に加熱して８時間保持し、重合反応を進行させてポリマービーズを製造した。得られたポリマービーズの顕微鏡写真を撮影し、その平均粒径及び均一係数を求めたところ、平均粒径は３３０μｍ、均一係数は１．０７であった。
【００７６】
続いて、このポリマービーズ１０ｇを、ジクロロエタン２０ｇ、９８％硫酸１００ｇと共に、冷却管付き４つ口フラスコに入れ、攪拌下、１００℃で４時間かけて反応させた。反応液を冷却後、希硫酸、続いて水を用いて順次置換した。得られた粒子を濾過した後、カラムに充填し、３０ＢＶの４％塩化ナトリウム溶液を通液し、その後３０ＢＶの水を通液して水洗することにより、Ｎａ形のカチオン交換樹脂を得た。得られたカチオン交換樹脂の顕微鏡写真を撮影し、その平均粒径及び均一係数を求めたところ、平均粒径は４７０μｍ、均一係数は１．０５であった。
【００７７】
［比較例１］
実施例１において、管Ｂを閉じて親水性液体の流通を行なわず、疎水性液体のみを１５ｍｌ／ｈで通液した以外は、実施例１と同様の手順で実験を行なったところ、管Ｃから水性媒質中に放出された疎水性液体は合一してしまい、液滴粒子の形態を有さなかった。
【００７８】
［比較例２］
キシダ化学製スチレン８６ｇと、三共化成製５７％ジビニルベンゼン１４ｇと、ナカライテスク製７５％ベンゾイルパーオキサイド０．６７ｇとの混合液、及び、５００ｍｌの０．１％クラレ製ＰＶＡ溶液を、１Ｌの反応フラスコに入れ、撹拌下、８０℃に加熱して８時間保持し、重合反応を進行させてポリマービーズを製造した。得られたポリマービーズの顕微鏡写真を撮影し、平均粒径及び均一係数を求めたところ、平均粒径は３６０μｍ、均一係数は１．５０であった。
【００７９】
【発明の効果】
本発明によれば、複数の流入路が合流して一の流出路に至る流路構造を用い、疎水性液体と親水性液体とを別々の流入路から導入して合流させることにより、均一な量の疎水性液体を断続的に水性媒質中に放出させているので、流量の厳密な制御を必要とせず、且つ、熱の発生や安全面の課題等を伴うことなく、液の合一による大粒径の液滴の発生を原理的に防ぎながら、均一性の高い疎水性液滴及びポリマービーズを、簡素な設備により工業的規模で安定的に製造することができる。また、得られたポリマービーズを用いて、均一性の高いイオン交換樹脂を工業的規模で安定的に製造することができる。
【図面の簡単な説明】
【図１】本発明の一実施形態に係るポリマービーズの製造装置の構成を模式的に表わす図である。
【図２】（Ａ），（Ｂ）は何れも、図１に示すポリマービーズの製造装置における流路部の構成の例を模式的に表わす図である。
【図３】本発明の一実施形態の変形例に係るポリマービーズの製造装置の構成を模式的に表わす図である。
【図４】本発明の一実施形態に係る疎水性液体の製造装置の構成を模式的に表わす図である。
【図５】本発明の一実施形態の変形例に係るポリマービーズの製造装置及び疎水性液体の製造装置の部分的な構成を模式的に表わす図である。
【図６】本発明の参考文献（４^ｔｈ Ｉｎｔ． Ｃｏｎｆ． ｏｎ Ｍｉｃｒｏｒｅａｃｔｉｏｎ Ｔｅｃｈｎｏｌｏｇｙ （Ｍａｒｃｈ ２０００） ｐ１３３−１４０）を説明するための図である。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for producing a hydrophobic droplet, a method and an apparatus for producing a polymer bead, and a method for producing an ion exchange resin. More specifically, a method for producing hydrophobic droplets having a uniform particle size, a method and apparatus for producing polymer beads having a uniform particle size using the hydrophobic droplets having a uniform particle size obtained thereby, and a method for producing uniform droplets The present invention relates to a method for producing an ion exchange resin having a diameter.
[0002]
[Prior art]
Conventionally, when producing a granular resin (polymer beads) having a uniform particle size, for example, when producing particles of a styrene / divinylbenzene copolymer which has been used for a long time as a base bead of an ion exchange resin, A suspension polymerization method is used in which a hydrophobic monomer-containing liquid is dispersed in an aqueous medium into particles and the dispersed particles are polymerized.
[0003]
However, in this method, the particle size of the obtained polymer particles depends on the particle size of the hydrophobic droplets in the aqueous medium. Due to the variation, there is a problem that the particle size of the polymer particles obtained by the polymerization also varies.
[0004]
Therefore, prior to the polymerization, a method has been proposed in which an oil-in-water dispersion in which monomer-containing droplets having a uniform particle size are dispersed by another apparatus is prepared, and the dispersion is charged into a polymerization vessel and polymerized. .
[0005]
As a method of producing an oil-in-water dispersion having a uniform particle size, a nozzle plate having an upwardly formed ejection hole is provided at a lower portion of a container filled with water, and a monomer-containing liquid is supplied into water through the ejection hole. By doing so, a method of dispersing and generating monomer-containing droplets having a uniform particle size in water has been proposed (for example, Patent Document 1).
[0006]
However, in order to generate uniform monomer-containing droplets by using this method, the flow rate at the time of supplying the monomer-containing liquid must be uniquely determined based on the diameter of the ejection hole, the physical properties of the monomer, and the like. If the jetting is performed at a flow rate other than the flow rate uniquely determined, the particle size distribution of the obtained monomer-containing droplets covers a wide range. Therefore, in order to obtain monomer-containing droplets having a uniform particle size (particle size distribution is restricted) using the same method, it is necessary to supply the monomer-containing liquid within a limited range of operating conditions. is there. Due to the strictness of such operating conditions, there is a limit to industrial mass production using this method.
[0007]
Therefore, as a method of improving this method to produce uniform monomer-containing droplets or polymer beads with a narrow particle size distribution, the monomer-containing liquid is forcibly ejected from the orifice while applying vibration to the monomer-containing liquid. A method has been proposed in which the jet flow of the monomer-containing liquid is broken to make the particle size uniform (for example, Patent Documents 2 and 3).
[0008]
However, according to these methods, although it is possible to stably generate droplets with higher uniformity, equipment having a complicated structure is required to apply vibration, which is expensive, and requires operation and operation. There is a problem that maintenance becomes complicated. In addition, since heat is generated due to vibration, it is necessary to take sufficient safety measures.In addition, when jetting a thermopolymerizable monomer, the monomer near the jet port is polymerized by heat and the There is a problem that blockage is caused and the ejection pressure increases. Further, since the apparatus is greatly deteriorated due to vibration and heat, it is difficult to carry out this method continuously for a long time on an industrial scale.
[0009]
In addition, in any of the above methods, since the hydrophobic liquid is continuously ejected from the ejection hole into the aqueous medium, there is a problem that a small amount of large-sized droplets are generated due to coalescence of the liquid at the time of ejection. In order to produce uniform polymer beads, it is necessary to remove such large-diameter droplets in a subsequent step, and the operation is very complicated.
[0010]
The uniform monomer phase droplets obtained by the various methods described above are then polymerized using a suspension polymerization technique. Various methods have been proposed for a suspension polymerization technique for producing polymer beads having a uniform particle size by polymerizing while maintaining the uniformity of the particle size of the monomer phase droplets.
[0011]
For example, Patent Document 4 discloses that a mixture of a polymerizable monomer and a polymerization initiator is ejected through an ejection hole into an aqueous medium containing a suspension stabilizer forming a continuous phase, thereby forming monomer phase droplets. And partially polymerizing the monomer phase droplets, and then completing the polymerization of the partially polymerized monomer phase droplets in a reaction vessel. This reactor is specially designed and has a stirring function for the polymerization of monomer phase droplets. Therefore, if monomer phase droplets having a uniform particle size can be formed, polymer beads having a uniform particle size can be produced by polymerizing the monomer phase droplets using the disclosed method.
[0012]
Further, as another method, for example, Patent Literature 5 discloses that a droplet having a uniform particle diameter obtained by the method disclosed in Patent Literature 2 described above is mixed with a suspension medium (temperature: (About 40-50 ° C.), transferred to a polymerization reactor and then polymerized using conventional techniques. As described above, this polymerization technique is a conventionally known batch polymerization technique in which a suspension medium is stirred while serving as a polymerization medium, and the monomer is heated under free radical forming conditions. . In conventional suspension polymerization technology, in continuous suspension polymerization of vinyl compounds, a small amount of the polymer to be manufactured is mixed with the monomer to be suspended in the polymerization medium, or the type and amount of the suspending agent are changed. Thus, coalescence of suspended monomer droplets can be reduced. Therefore, if suspension monomer droplets having a uniform particle size can be formed, polymer beads having a uniform particle size can be produced by polymerizing the suspension monomer droplets using the proposed method. Become.
[0013]
The polymer beads having a uniform particle size produced in this manner can be used for various purposes by imparting desired properties by various treatments. For example, by introducing a desired ion-exchange group into the polymer beads having a uniform particle size, an ion-exchange resin having a uniform particle size can be produced.
[0014]
[Patent Document 1]
JP-A-49-55782
[Patent Document 2]
Japanese Patent Publication No. 1-28761 (JP-A-57-102905)
[Patent Document 3]
JP-A-7-39743
[Patent Document 4]
US Patent No. 392255
[Patent Document 5]
JP-A-5-194611
[0015]
[Problems to be solved by the invention]
As described above, in the conventional method in which a hydrophobic liquid is continuously ejected from an ejection hole into an aqueous medium to generate hydrophobic droplets, the operating conditions are severely restricted, and the large particle size due to the coalescence of the liquid is used. There were problems such as generation of droplets. In addition, it is difficult to say that these problems have been completely solved even in an improved method of applying mechanical vibration at the time of ejecting the hydrophobic liquid to break the ejected flow of the hydrophobic liquid. New issues have arisen, such as the generation of heat and the need for safety measures.
[0016]
The present invention has been made in view of the above problems. That is, the object of the present invention is to generate a droplet having a large particle size by combining liquids without the need for strict control of the flow rate and without accompanying the generation of heat or safety issues. To provide a method and apparatus for stably producing hydrophobic droplets and polymer beads having high uniformity on an industrial scale with simple equipment, and to obtain uniformity using the obtained polymer beads. To provide a method for producing an ion-exchange resin having a high water content.
[0017]
[Means for Solving the Problems]
The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, by intermittently discharging a uniform amount of a hydrophobic liquid into an aqueous medium, the generation of large droplets due to the coalescence of the liquids. It has been found that hydrophobic droplets having a uniform particle size can be easily generated while preventing the above in principle.
[0018]
Here, the present inventors have described a literature (4) regarding a microreactor for nitrating benzene and toluene. ^th Int. Conf. on Microreaction Technology (March 2000) p133-140) and literature on tubular reactors that produce calcium carbonate precipitates (AIChE Journal, 46, 6, 1241, June 2000). According to the former document, when a hydrophobic liquid and a hydrophilic liquid are allowed to flow under predetermined conditions from inlet pipes α and β, respectively, in a T-shaped pipe having the structure shown in FIG. Are alternately distributed and pass through the outlet pipe γ. In the latter document, two types of reaction liquids A and B (for example, a calcium chloride solution and an ammonium carbonate solution) and one type of immiscibility are used for a tube reactor having a pipe structure branched in four directions. When the fluid C (for example, air) is introduced, the two types of reaction liquids A and B are mixed and a reaction occurs, and the reaction liquid A and the immiscible fluid C also have an alternate structure in the tube.
[0019]
With reference to the above technology, the present inventors used a flow channel structure in which a plurality of inflow channels merged to one outflow channel, and in a state where an aqueous medium was disposed on the outflow channel side, a hydrophobic liquid and a hydrophilic liquid were used. It has been found that a uniform amount of the hydrophobic liquid can be discharged alternately with the hydrophilic liquid into the aqueous medium from the outflow path when the liquid and the liquid are introduced from different inflow paths and merged. Here, since the hydrophilic liquid is mixed with the aqueous medium, as a result, a uniform amount of the hydrophobic liquid is intermittently released into the aqueous medium, and the above problem is effectively solved. They have found and completed the present invention.
[0020]
That is, the gist of the present invention is that, in a flow channel structure in which a plurality of inflow channels merge to form one outflow channel, a hydrophobic liquid and a hydrophilic liquid are introduced from separate inflow channels, and the flow channel structure includes Merging, discharging the resulting mixed liquid into the aqueous medium from the outflow channel, and dispersing the hydrophobic liquid in the mixed liquid into the aqueous medium, thereby producing droplets composed of the hydrophobic liquid. (Claims 1 and 2).
[0021]
Further, another gist of the present invention is to introduce a hydrophobic liquid and a hydrophilic liquid containing a polymerizable monomer from separate inflow paths in a flow path structure in which a plurality of inflow paths merge to one outflow path. And merged in the flow channel structure, the obtained mixed liquid is discharged into the aqueous medium from the outflow path, and the hydrophobic liquid in the mixed liquid is dispersed in the aqueous medium, thereby removing the hydrophobic liquid from the hydrophobic liquid. The present invention also provides a method for producing polymer beads, characterized in that a liquid droplet is obtained, and the polymerizable monomer in the liquid droplet is further polymerized.
[0022]
Further, another gist of the present invention is to provide a channel portion having a channel structure in which a plurality of inflow channels merge to one outflow channel, a hydrophobic liquid containing a polymerizable monomer, A hydrophobic liquid introducing means for introducing into at least one inflow path, a hydrophilic liquid introducing means for introducing a hydrophilic liquid into at least one other inflow path of the flow path section, and the outflow path side of the flow path section A hydrophobic droplet production tank holding an aqueous medium, a polymerization reaction tank connected to the hydrophobic droplet production tank and polymerizing the polymerizable monomer, and introduced by the hydrophobic liquid introduction means. The hydrophobic liquid and the hydrophilic liquid introduced by the hydrophilic liquid introducing means are combined in the flow path structure of the flow path section, and the resulting mixed liquid is produced from the outflow path by the production of the hydrophobic droplet. Release into the aqueous medium of the tank and disperse the hydrophobic liquid in the mixture in the aqueous medium Producing a droplet composed of the hydrophobic liquid, further introducing the droplet into the polymerization reaction tank, and polymerizing the polymerizable monomer in the droplet, producing polymer beads. The present invention resides in a device (claim 5).
[0023]
Further, another gist of the present invention resides in a method for producing an ion exchange resin, characterized in that an ion exchange group is introduced into the obtained polymer beads in the method for producing a polymer bead described above (claim 6).
[0024]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a configuration of an apparatus for producing polymer beads according to an embodiment of the present invention (hereinafter, abbreviated as “apparatus for producing polymer beads of this embodiment” or simply “production apparatus of this embodiment”). It is a figure showing typically.
[0025]
As shown in FIG. 1, a polymer bead manufacturing apparatus 10 according to the present embodiment includes, as constituent elements related to the production of hydrophobic droplets, a flow in which a plurality of inflow channels A and B merge to reach one outflow channel C. A channel portion 20 having a channel structure, a hydrophobic liquid storage tank 30 for holding a hydrophobic liquid, and a hydrophobic liquid for feeding the hydrophobic liquid in the hydrophobic liquid storage tank 30 into the inflow path A of the channel portion 20. A liquid feed pump 31, a hydrophilic liquid storage tank 40 for holding the hydrophilic liquid, and a hydrophilic liquid feed for feeding the hydrophilic liquid in the hydrophilic liquid storage tank 40 to introduce the hydrophilic liquid into the inflow path B of the flow path unit 20. A pump 41 and a hydrophobic droplet production tank 50 for holding an aqueous medium forming a continuous phase in order to disperse the hydrophobic liquid discharged from the outflow path C of the flow path section 20 into droplets. I have.
[0026]
In the flow path section 20, the number of inflow paths is not particularly limited as long as the number is plural. FIG. 1 shows an example in which the flow path section 20 has two inflow paths A and B.
[0027]
The diameters of the inflow paths A and B and the outflow path C are not particularly limited, but are usually 1 μm or more, preferably 10 μm or more, and usually 5000 μm or less so that the generated hydrophobic droplets can be stably present. Preferably it is in the range of 1000 μm or less. The ratio of the diameters of the plurality of inflow passages A and B is not particularly limited, but is preferably the same in order to cause the hydrophobic liquid and the hydrophilic liquid to merge without difficulty. Further, the ratio between the diameters of the inflow passages A and B and the diameter of the outflow passage C is not particularly limited, but is usually 5: 1 to 1: 5, preferably 2 to prevent disturbance of the combined liquid. : 1 to 1: 2.
[0028]
The respective cross-sectional shapes of the inflow passages A and B and the outflow passage C are not particularly limited, and may be circular, triangular, quadrangular, or other shapes. Preferably, there is.
[0029]
In addition, the angle of connection between the inflow channels A and B and the outflow channel C is not particularly limited, and may be configured so as to take an arbitrary angle with each other. However, the hydrophobic liquid and the hydrophilic liquid are merged without difficulty. It is preferable to set the bond angle such that the bond angle can be distributed. As a typical coupling shape between the inflow channels A and B and the outflow channel C when there are two inflow channels A and B, a T-shaped shape shown in FIG. A Y-shape is exemplified.
[0030]
The diameters of the inflow path and the outflow path, and their ratios, cross-sectional shapes, and coupling shapes are all factors that affect the particle diameter of the hydrophobic droplets. It is necessary to appropriately set the particle diameter of the target hydrophobic droplet while considering the physical properties of the liquid and the aqueous medium.
[0031]
The channel section 20 may be formed of a single member or a plurality of members as long as the channel section has the above-described channel structure. In the latter case, for example, a plurality of pipes for the inflow path and one pipe for the outflow path can be easily formed by connecting them at one point using a connecting member. The material of these members is not particularly limited as long as they do not show reactivity with a hydrophobic liquid, a hydrophilic liquid, and an aqueous medium described later, but from the viewpoint of price and durability, metal such as stainless steel is used. A material made of a polymer material such as polystyrene or Teflon (registered trademark) is preferable.
[0032]
In addition, the hydrophobic liquid storage tank 31 and the hydrophobic liquid supply pump 32 together serve as a hydrophobic liquid introduction unit for introducing the hydrophobic liquid into the inflow path A of the flow path unit 20, and a hydrophilic liquid storage tank 41. The hydrophilic liquid feed pump 42 and the hydrophilic liquid feed pump 42 together function as a hydrophilic liquid introducing unit that introduces the hydrophilic liquid into the inflow path B of the flow path unit 20.
[0033]
Further, the polymer bead manufacturing apparatus 10 of the present embodiment includes an aqueous medium storage tank 51 for holding an aqueous medium supplied to the hydrophobic droplet production tank 50, An aqueous medium feed pump 52 for feeding the aqueous medium in the medium storage tank 51 to supply it to the hydrophobic droplet manufacturing tank 50, and an aqueous medium sent by the aqueous medium feed pump 52 to the hydrophobic droplet manufacturing tank An aqueous medium discharging portion 53 for discharging into the liquid droplets 50; a polymerization reaction tank 60 for polymerizing the hydrophobic liquid droplets generated in the hydrophobic liquid droplet producing tank 50 without being crushed; A hydrophobic droplet transfer pipe 61 for transferring from the hydrophobic droplet production tank 50 to the polymerization reaction tank 60 together with the aqueous medium; and stirring to maintain a uniform state of the hydrophobic droplets in the polymerization reaction tank 60 during the polymerization reaction. The hydrophobic droplet stirring means 62 Obtain.
[0034]
Here, since the hydrophobic droplet production tank 50 and the polymerization reaction tank 60 are connected by the hydrophobic droplet transfer pipe 61, the aqueous medium 11 is transferred from the aqueous medium discharge unit 53 into the hydrophobic droplet production tank 50. By the supply, a floating upstream of the aqueous medium can be formed in the hydrophobic droplet producing tank 50, and the hydrophobic droplet produced in the hydrophobic droplet producing tank 50 can be formed in the aqueous medium by the floating upstream. , And can be continuously transferred to the polymerization reaction tank 60.
[0035]
The polymerization reaction tank 60 is provided with means (not shown) for adding appropriate radical generation conditions (polymerization initiation conditions) according to the type of radical polymerization initiator contained in the hydrophobic liquid described below. For example, when a thermal radical polymerization initiator is used, heating means (for example, means for performing steam heating) is provided on the outer peripheral side of the polymerization reaction tank 60, and the contents in the polymerization reaction tank 60 are subjected to radical generation conditions. For example, it is configured so that it can be heated to a temperature condition of 40 to 150 ° C. Further, by adding polymerization reaction conditions while stirring the inside of the polymerization reaction tank 60 by the hydrophobic droplet stirring means 62, the ethylenic monomer in the droplets can be removed while maintaining the uniformity of the particle diameter of the hydrophobic droplets. It is possible to polymerize.
[0036]
Subsequently, a method for producing polymer beads (hereinafter, abbreviated as “a method for producing polymer beads of the present embodiment” or simply “a method for producing the present embodiment” as appropriate) performed by the production apparatus 10 of the present embodiment will be described. I do.
[0037]
In the method for producing polymer beads of the present embodiment, a step (droplet production step) of producing droplets (hydrophobic droplets) of a uniform particle size composed of a hydrophobic liquid containing a polymerizable monomer is obtained. A step of polymerizing the polymerizable monomer in the hydrophobic droplets to finally obtain the target polymer beads (polymerization reaction step).
[0038]
First, in the droplet generation step, the outflow path C of the flow path section 20 is immersed in the aqueous medium of the hydrophobic droplet production tank 50, and the hydrophobic liquid containing the polymerizable monomer and the hydrophilic liquid are separately separated. Of the mixed liquid into the aqueous medium by dispersing the hydrophobic liquid in the mixed liquid into the aqueous medium by introducing the mixed liquid into the aqueous medium through the outflow path C. As a result, a droplet composed of a hydrophobic liquid is generated.
[0039]
As the hydrophobic liquid, a liquid containing a polymerizable monomer, a polymerization initiator, and other components used as necessary is used.
[0040]
The type of the polymerizable monomer is not particularly limited, and any type can be used as long as it is a polymerizable monomer. Usually, an ethylenic monomer is used. Since the ethylenic monomer is a medium having high polymerizability and excellent compatibility, it can be used in combination with other various monomers, hydrophobic solvents, polymer compounds and the like.
[0041]
The type of the ethylenic monomer is not particularly limited, and any one that can be used for suspension polymerization can be used. Specific examples include styrene, o-methylstyrene, p-methylstyrene, m-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,4-dichlorostyrene, p-ethylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene and the like Styrene and its derivatives, polyvinyl aromatic compounds such as divinylbenzene, divinyltoluene, divinylxylene and trivinylbenzene, organic acid vinyl esters such as vinyl acetate, vinyl propionate and vinyl benzoate, methacrylic acid, methyl methacrylate, methacrylic Ethyl acrylate, propyl methacrylate, n-methacrylate Methacrylic acid and its derivatives such as butyl, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, dimethylaminomethyl methacrylate, acrylic acid, acrylic acid Acrylic acid and its derivatives such as methyl, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-octyl acrylate, dodecyl acrylate, stearyl acrylate, phenyl acrylate, vinyl methyl ketone, vinyl Vinyl ketones such as hexyl ketone, N-vinyl compounds such as N-vinyl pyrrole, N-vinyl carbazole, N-vinyl pyrrolidone, vinyl naphthalenes, acrylonitrile, methacrylonitrile, Riruamido, and the like. Any one of the above-mentioned ethylenic monomers may be used alone, and if necessary, two or more may be used in any combination and composition. Among the ethylenic monomers exemplified above, preferred ones include styrene, divinylbenzene, methacrylic acid, methyl methacrylate, acrylic acid, and methyl acrylate. When two or more ethylenic monomers are used in combination, for example, in order to obtain crosslinked polymer beads, a monovinyl compound such as styrene and a polyvinyl compound such as divinylbenzene may be used in combination.
[0042]
There is no particular limitation on the type of the polymerization initiator, and depending on the type of the polymerizable monomer to be polymerized, an appropriate one may be selected from various known polymerization initiators. The radical polymerization initiator conventionally used for polymerizing the above-mentioned ethylenic monomer is preferable. Specific examples of the radical polymerization initiator include those soluble in a polymerizable monomer, such as peroxide polymerization initiators such as benzoyl peroxide (BPO), lauroyl peroxide, t-butyl hydroperoxide, and azoisobutyronitrile. Azo-based polymerization initiators such as (AIBN) and 2,2′-azobis (2,4-dimethylvaleronitrile) (trade name: V-65 (Wako Pure Chemical Industries, Ltd.)). Persulfate, hydrogen peroxide, hydroperoxide and the like can be mentioned. Above all, a peroxide-based polymerization initiator or an azo-based polymerization initiator is preferable, and specifically, BPO and AIBN are preferable.
[0043]
The hydrophobic liquid may contain other components as necessary. Examples of other components include pore-forming agents, which are materials that impart a porous structure to the resulting polymer. As the pore-forming agent, any substance can be used as long as it is a substance that is soluble in the polymerizable monomer and does not participate in the polymerization reaction and does not have an undesired effect of dissolving the formed polymer. Can be used. In addition, one kind may be used alone, and two kinds or more may be used together in optional combination and composition. Preferred specific examples of the pore-forming agent include organic solvents represented by aliphatic hydrocarbons such as hexane, toluene, and isooctane, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polyvinyl acetate, polystyrene, and nylon. High molecular compounds having a molecular weight of about 1,000 to 100,000 are exemplified. Among them, toluene, isooctane and the like are preferable. The physical properties of the porous structure can be adjusted by the type, amount used, molecular weight, etc., of the organic solvent or polymer used, and details thereof are described in Macromolecules, Vol. 24, p. 117 (1991).
[0044]
A hydrophobic liquid is composed of a combination of one or two or more polymerizable monomers, a polymerization initiator, and a component such as a pore-forming agent contained as necessary. The physical properties (viscosity, specific gravity, interfacial tension) of liquids differ greatly. Therefore, the specific gravity of the hydrophobic liquid is preferably at least 0.8, more preferably at least 0.85, and preferably at most 1.4, more preferably at most 1.3, and the viscosity is preferably at most 0. It is adjusted to 0.1 cps (centipoise) or more, more preferably 0.2 cps or more, particularly preferably 0.4 cps or more, and preferably 200 cps or less, more preferably 100 cps or less, and particularly preferably 50 cps or less. When the hydrophobic droplet is suspended in the aqueous medium, the difference between the specific gravity of the aqueous medium and the specific gravity of the hydrophobic droplet (hydrophobic liquid) (the specific gravity of the aqueous medium−the specific gravity of the hydrophobic droplet) is zero. It is preferably larger than 0.5 and not more than 0.5. The specific gravity of the hydrophobic liquid is often 1 or less, but the specific gravity may exceed 1 depending on the composition, for example, when a polymerizable monomer having a halogen atom is used. On the other hand, when the aqueous medium is mainly composed of water, the specific gravity is around 1. Therefore, when the specific gravity of the hydrophobic droplet exceeds 1, the specific gravity of the aqueous medium is dissolved in water by dissolving substances such as sodium chloride and calcium chloride that do not affect the hydrophobic droplet in water. The difference between the specific gravity of the aqueous medium and the specific gravity of the hydrophobic droplet is usually larger than 0, preferably 0.05 or more, and usually 0.5 or less, preferably 0.4. preferable. When the specific gravity of the hydrophobic liquid is larger than that of the aqueous medium, the hydrophobic liquid droplet manufacturing tank 50 is inverted together with the flow path section 20 and the outflow path C of the flow path section 20 is directed downward, so that the hydrophobic liquid is produced. It is possible for the droplets to settle.
[0045]
The hydrophilic liquid is a substance that is liquid at normal temperature, is immiscible with the above-mentioned hydrophobic liquid, and is a substance that is inactive with respect to each component of the above-mentioned hydrophobic liquid. Not restricted. However, since the physical properties (viscosity, specific gravity, interfacial tension) of the above-mentioned hydrophobic liquid vary greatly depending on the type and composition of the components, substances having appropriate physical properties that do not mix with the hydrophobic liquid to be used depending on the physical properties of the hydrophobic liquid to be used Is preferably used as the hydrophilic liquid.
[0046]
As the hydrophilic liquid, a solution in which an appropriate amount of a dispersion stabilizer and, if necessary, other components are dissolved in water is used. Here, the purpose of the dispersion stabilizer (suspension agent) is to maintain the hydrophilic liquid and the hydrophobic liquid in an immiscible state when the hydrophilic liquid is merged with the hydrophobic liquid in the above-described channel structure. Used in. The kind of the dispersion stabilizer is not particularly limited, and among various known dispersion stabilizers used in a normal suspension polymerization method or the like, it can be stably dispersed according to the physical properties of the above-mentioned hydrophobic liquid. Those are appropriately selected and used. In addition, any one kind may be used alone, and if necessary, two or more kinds may be used in an arbitrary combination and composition. Specific examples of the dispersion stabilizer include high molecular organic compounds such as gelatin, polyvinyl alcohol, starch, polyacrylamide, cellulose ethers (such as carboxymethyl-methylcellulose), and water-inactive inorganic compounds such as magnesium silicate. . Among them, gelatin and polyvinyl alcohol are preferred. The amount of the dispersion stabilizer used may be appropriately determined in accordance with the physical properties of the hydrophobic liquid from the viewpoint of maintaining a state of being immiscible with the hydrophobic liquid droplets in the channel structure. It is used in an amount of usually 0.001% by weight or more, preferably 0.05% by weight or more, and usually 2% by weight or less, preferably 1% by weight or less based on the total weight of the conductive medium.
[0047]
The aqueous medium is not miscible with the above-mentioned hydrophobic liquid, can be suitably dispersed as droplets, and if it does not show activity for each component of the above-described hydrophobic liquid, The type is not particularly limited. Generally, a solution in which an appropriate amount of a dispersion stabilizer and, if necessary, other components are dissolved in water is used as in the case of the above-mentioned hydrophilic liquid. In the aqueous medium, the dispersion stabilizer is used for the purpose of suppressing the binding and coalescence of the droplets when the hydrophobic droplets are generated. The kind of the dispersion stabilizer is not particularly limited, and a dispersion stabilizer capable of stably dispersing a hydrophobic liquid is appropriately selected and used from the various known dispersion stabilizers exemplified above. Any one kind may be used alone, and two or more kinds may be used in optional combination and composition. Further, the same dispersion stabilizer as in the case of the hydrophilic liquid may be used, or a different dispersion stabilizer may be used, but it is preferable that they are the same. The amount of the dispersion stabilizer used may be determined by correlating with the physical properties of the hydrophobic liquid from the viewpoint of maintaining the uniformity of the particle size without coalescing and crushing the generated hydrophobic droplets. Specifically, it is usually 0.01% by weight or more, preferably 0.05% by weight or more, and usually 5% by weight or less, preferably 1.5% by weight or less based on the total weight of the aqueous medium. . It is preferable that the concentration of the dispersion stabilizer in the aqueous medium is equal to or higher than the concentration of the dispersion stabilizer in the hydrophilic liquid.
[0048]
The hydrophilic liquid and the aqueous medium may each contain other components as necessary. Examples of other components include a polymerization inhibitor that suppresses the polymerizable monomer leaked from the hydrophobic droplets to the aqueous medium from polymerizing in the aqueous medium. As the polymerization inhibitor, from various known polymerization inhibitors, those which show appropriate water-solubility so as to be dissolved in a hydrophilic liquid and an aqueous medium, and not to be dissolved in a hydrophobic liquid are appropriately selected and used. . One type may be used alone, or two or more types may be used in any combination and composition. Examples of the type of the polymerization inhibitor include nitrite, thiocyanate, and methylene blue. The amount of the polymerization inhibitor used may be determined in accordance with the physical properties of the hydrophobic liquid from the viewpoint of reliably suppressing the polymerization of the leaked polymerizable monomer. It is usually 0.1 ppm by weight or more, preferably 1 ppm by weight or more, and usually 10000 ppm by weight or less, preferably 1000 ppm by weight or less based on the total weight. The polymerization inhibitor may be contained in both the hydrophilic liquid and the aqueous medium, or may be contained only in the aqueous medium.
[0049]
The temperature of the hydrophobic liquid and the hydrophilic liquid when performing the droplet generation step is not particularly limited, but is usually 0 ° C. or higher, preferably 10 ° C. or higher, and is usually 100 ° C. or lower, preferably 50 ° C. or lower. Range. The temperature of the aqueous medium is not particularly limited, but is usually 0 ° C. or higher, preferably 10 ° C. or higher, and is usually 100 ° C. or lower, preferably 40 ° C. or lower. It is preferable to appropriately select appropriate values for these temperatures according to the types of the hydrophobic liquid and the hydrophilic liquid to be used, the conditions for liquid passage, the type of the aqueous medium to be used, the target particle size, and the like.
[0050]
The flow rates when the hydrophobic liquid and the hydrophilic liquid are introduced into the corresponding inflow channels A and B are not particularly limited, but in any case, the Reynolds number is usually 0.1 or more, especially 1 or more, and usually 300 or less. Especially, the range of 100 or less is preferable. The Reynolds number is defined by the following equation.
(Equation 1)

[0051]
Further, the equivalent diameter in the above equation is defined by the following equation.
(Equation 2)

[0052]
These flow rates may be appropriately set according to the type of the hydrophobic liquid and the hydrophilic liquid to be used, the shape of the flow path structure of the flow path section 20, the type of the aqueous medium to be used, the target particle diameter, and the like. It is preferred to choose. In addition, the ratio of the flow rates of the hydrophobic liquid and the hydrophilic liquid is not particularly limited, but from the viewpoint of keeping the amount of the hydrophobic liquid released into the aqueous medium constant, the flow rates should be substantially the same. More specifically, the ratio of the flow rate of the hydrophilic liquid to the flow rate of the hydrophobic liquid is preferably 0.5 or more, more preferably 0.8 or more, and usually 2 or less, especially 1.2 or less.
[0053]
When the hydrophobic liquid and the hydrophilic liquid are introduced from the corresponding inflow paths A and B under the above conditions, the hydrophobic liquid and the hydrophilic liquid merge in the channel structure to form a mixed liquid. In this mixed liquid, the hydrophobic liquid and the hydrophilic liquid are not mixed with each other, but are alternately arranged by a fixed amount while maintaining the immiscible state, and pass through the outflow channel C. It is discharged into the aqueous medium alternately from the outlet of C. Here, since the hydrophilic liquid is mixed with the aqueous medium simultaneously with the release, a certain amount of the hydrophobic liquid is intermittently released into the aqueous medium and dispersed. Therefore, it is possible to generate droplets having a uniform particle size while preventing the generation of droplets having a large particle size due to coalescence of liquids in principle.
[0054]
The hydrophobic droplets obtained by the above-described droplet generation step are subsequently introduced into the polymerization reaction tank 60, and provided for the polymerization reaction step. In the polymerization reaction step, appropriate polymerization reaction conditions are added to the hydrophobic droplets in the polymerization reaction tank 60 to polymerize the ethylenic monomer in the droplets while maintaining the uniformity of the particle size of the hydrophobic droplets. This converts it into polymer beads.
[0055]
The conditions for initiating the polymerization reaction may be appropriately selected according to the type of the polymerization initiator contained in the hydrophobic droplets.In the case of a radical polymerization initiator, the radical generation is promoted by heating or light irradiation, for example. Initiate the polymerization reaction. When a thermal radical polymerization initiator is used, the temperature to be added varies depending on the type of the polymerization initiator, but is usually 30 ° C. or higher, preferably 60 ° C. or higher, and usually 150 ° C. or lower, preferably 100 ° C. or lower. The pressure at the time of the polymerization varies depending on the above-mentioned various conditions, the polymerization temperature, and the like. In the case of pressurizing conditions, usually, the range of 1 MPa or less is preferable.
[0056]
The time of the polymerization reaction varies depending on the composition of the polymerizable monomer contained in the hydrophobic droplet, but is usually in the range of 6 hours to 10 hours. Since the polymerization reaction takes a long time, agitation is applied to suppress the coalescence and crushing of the hydrophobic droplets, maintain the uniformity of the particle size, and keep the dispersion state of the hydrophobic droplets uniform. It is necessary. The stirring conditions vary depending on the inner diameter of the polymerization reaction tank 60, the shape of the stirring means 62, the physical properties of the polymerizable monomer contained in the hydrophobic droplets, the particle size of the hydrophobic droplets, and the like. It is possible to uniquely determine the optimum condition to be maintained. As specific stirring conditions, for example, the descriptions in Patent Documents 4 and 5 described above can be referred to.
[0057]
After completion of the polymerization reaction, the obtained polymer beads in a solid state are separated and recovered from the aqueous medium by a known dehydration technique such as filtration or a solid-liquid separation technique.
[0058]
Unpolymerized polymerizable monomers, organic solvents, polymer substances, surfactants, salts and the like remain in the obtained polymer beads. Therefore, it is preferable to remove these residual components by washing with a solvent such as water or an organic solvent. Examples of the organic solvent include methanol, ethanol, isopropyl alcohol, acetone, methyl isobutyl ketone (MIBK), methyl-t-butyl ether (MTBE), toluene, chlorobenzene, ethylene dichloride, dichloromethane, chloroform and the like. The amount of the solvent used for washing varies depending on the type of the polymerizable monomer, the conditions of the polymerization reaction, and the like, but is usually 1 time or more, preferably 2 times or more, and usually 100 times or less, and preferably 10 times or more. Range below the amount. By heating the reaction product at the time of washing, the efficiency of washing can be increased. In this case, it is preferable to perform the cleaning while heating to a temperature equal to or lower than the boiling point of the solvent used for the cleaning. When water is used as the solvent, washing can be performed while passing water vapor in addition to water and hot water.
[0059]
Various treatments can be applied to the obtained polymer beads according to the purpose. For example, when polymer beads are used as an ion exchange resin, a treatment for introducing a target ion exchange group into the obtained polymer beads is performed. Various techniques are known for introducing an ion-exchange group into a polymer bead, and may be appropriately selected according to the type of the polymerizable monomer, the type of the ion-exchange group to be introduced, the amount to be introduced, and the like.
[0060]
The particle diameter of the hydrophobic droplet and the polymer bead obtained in the production method of the present invention can be measured based on a micrograph. The average particle size of the hydrophobic droplet is not particularly limited, but is usually 10 μm or more, preferably 100 μm or more, and is usually 2000 μm or less, preferably 1000 μm or less. Also, the average particle size of the polymer beads produced using the hydrophobic droplets is basically substantially the same as the average particle size of the hydrophobic droplets.
[0061]
Further, the uniformity of the particle diameters of the hydrophobic droplets and the polymer beads can be evaluated by a uniformity coefficient. The uniformity coefficient is, for example, “diamond ion ^R Droplets according to the method described in Ion Exchange Resin / Synthetic Adsorbent Manual [Basic Edition] "(Mitsubishi Chemical Corporation, Ion Exchange Resin Division, edited on January 10, 1995, 8th edition), pages 139 to 141. Alternatively, it can be determined from the particle size distribution of the polymer beads by the following equation.
[0062]
[Equation 3]

[0063]
The uniformity coefficient of the hydrophobic droplet obtained in this embodiment is usually 1.2 or less, preferably 1.1 or less. In addition, the uniformity coefficient of the polymer beads also has a value range that is almost the same as that of the hydrophobic droplet. The uniformity coefficient of a commercially available ion-exchange resin having a uniform particle size is usually in the range of 1.02 or more and 1.2 or less. Therefore, the polymer beads obtained in the present embodiment are the raw materials of the ion-exchange resin. It can be seen that the particles have a sufficiently practical level of particle size uniformity.
[0064]
The values of the average particle diameter and the uniformity coefficient change the conditions such as the shape of the flow channel structure of the flow channel portion 20, the types and flow rates of the hydrophobic liquid and the hydrophilic liquid to be used, and the type of the aqueous medium to be used. By doing so, it is possible to adjust appropriately.
[0065]
As described above, according to the manufacturing apparatus and the manufacturing method of the polymer beads of the present embodiment, a plurality of inflow paths are combined to use a flow path structure leading to one outflow path, and the hydrophobic liquid and the hydrophilic liquid are separately introduced. Since a uniform amount of the hydrophobic liquid is intermittently released into the aqueous medium by being introduced and merged from the channel, the generation of large-diameter droplets due to the coalescence of the liquids is prevented in principle, It is possible to easily generate hydrophobic droplets having a uniform particle size. Also, unlike the conventional method of continuously ejecting a hydrophobic liquid from an ejection hole into an aqueous medium to generate hydrophobic droplets, strict control of the flow rate is not required and reliable under a wide range of operating conditions. Thus, hydrophobic droplets having a uniform particle size can be obtained. Furthermore, unlike the conventional improved method of applying a mechanical vibration at the time of ejecting a hydrophobic liquid to break up the ejected flow of the hydrophobic liquid, the industrial equipment can be manufactured by simple equipment without generating heat or safety issues. Polymer beads having a uniform particle size can be stably produced on a target scale. Further, by using the obtained polymer beads and introducing an ion exchange group into the polymer beads, a highly uniform ion exchange resin can be stably produced on an industrial scale.
[0066]
Note that the polymer bead manufacturing apparatus 10 of the present embodiment has a configuration in which the flow path unit 20 has only one flow path structure in which a plurality of inflow paths merge to one outflow path. As a modified example, a configuration in which a plurality of such flow path structures are provided is also possible. FIG. 3 schematically shows a configuration of a polymer bead manufacturing apparatus 10 'according to a modification of the embodiment of the present invention. In FIG. 3, components denoted by the same reference numerals as those in FIG. 1 have the same functions, and thus description thereof will be omitted. As shown in FIG. 3, the manufacturing apparatus 10 ′ of the present modification includes a flow path portion 20 ′ having a plurality of flow path structures in which a plurality of inflow paths merge to one outflow path, and a hydrophobic liquid The hydrophobic liquid and the hydrophilic liquid sent from the liquid sending pump 31 and the hydrophilic liquid sending pump 41 are configured to be branched and introduced into the inflow paths of the plurality of flow path structures, respectively. According to the configuration of this modified example, it is possible to simultaneously generate many hydrophobic droplets from the outflow paths of the plurality of flow path structures, thereby increasing the productivity of polymer beads. In FIG. 3, the number of the flow dew structures included in the flow path unit 20 is four, but the number is not particularly limited, and may be an arbitrary number of two or more.
[0067]
Further, of the configuration of the polymer bead manufacturing apparatus 10 of the above-described embodiment and the modified example, only components related to the manufacture of hydrophobic droplets are made independent, and specialized in manufacturing hydrophobic droplets having a uniform particle size. It is also possible to configure the device. FIG. 4 schematically shows the configuration of a hydrophobic droplet manufacturing apparatus 70 according to an embodiment of the present invention. Note that, in FIG. 4, components denoted by the same reference numerals as those in FIG. 1 have the same functions, and thus description thereof will be omitted. As shown in FIG. 4, the hydrophobic droplet manufacturing apparatus 70 of the present embodiment includes, among the components of the polymer bead manufacturing apparatus 10 of the above-described embodiment, components related to the manufacturing of the hydrophobic droplet, It basically consists of the same components. In addition, the hydrophobic droplet production tank 50 ′ is agitated with an aqueous medium in the hydrophobic droplet production tank 50 ′ in order to maintain the uniformity of the particle diameter of the produced hydrophobic droplets. Means 53 are provided. With such a configuration, similar to the above-described apparatus 10 for producing polymer beads, it is not necessary to strictly control the flow rate, and it is not necessary to generate heat or have a problem in terms of safety. Hydrophobic droplets with high uniformity can be manufactured by simple equipment specialized for hydrophobic droplets while preventing generation of droplets having a diameter in principle.
[0068]
The hydrophobic droplets having a uniform particle diameter obtained by the production apparatus 70 may be used as a raw material for producing polymer beads as described above, but may be used for other purposes. Other purposes include crystallization (crystal formation) and the like. In this case, the components of the hydrophobic droplet are not limited to the components such as the polymerizable monomer described above, and various appropriate components may be obtained according to the purpose.
[0069]
The embodiments of the present invention have been described above. However, the present invention is not limited to these embodiments, and can be implemented with appropriate modifications without departing from the spirit of the present invention.
[0070]
In particular, regarding each component of the apparatus for producing polymer beads and hydrophobic droplets according to the present invention, their appearance, shape, bonding state, positional relationship, and the like are not limited to those described in the above embodiment. Can be freely changed as long as the functions described in (1) can be performed without hindrance. For example, as shown in FIGS. 1, 3, and 4, the flow path unit 20 is provided outside the hydrophobic droplet production tanks 50 and 50 ', and the outflow path is provided inside the hydrophobic droplet production tanks 50 and 50'. As a modified example, as shown in FIG. 5, the flow path portion 20 is provided outside the hydrophobic droplet production tanks 50 and 50 ', and only the inflow path is provided in the hydrophobic droplet production tank. It may be configured so as to extend outside 50, 50 '. FIG. 5 is a diagram schematically showing a partial configuration of an apparatus for manufacturing polymer beads and an apparatus for manufacturing hydrophobic droplets according to a modification of the above embodiment. The same reference numerals as in FIGS. The constituent elements with are provided with the same functions.
[0071]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples as long as it does not exceed the gist, and various modifications can be made. In the description of the present specification, “BV” represents Bed Volume (volume ratio with respect to the volume of the resin packed in the column).
[0072]
[Example 1]
SUS pipe having an inner diameter of 0.8 mm as a pipe A into which a hydrophobic liquid flows, SUS pipe having an inner diameter of 0.8 mm as a pipe B into which a hydrophilic liquid flows, and a pipe C through which a mixed liquid of a hydrophobic liquid and a hydrophilic liquid flows out SUS pipes having an inner diameter of 0.1 mm are connected as a SUS T-shaped pipe having an inner diameter of 0.3 mm, and two inflow paths (tube A and pipe B) join to form one outflow path (tube C). ) Was created. The outlet of the pipe C (outflow channel) was immersed in an aqueous medium.
[0073]
As the hydrophobic liquid, a mixed solution of 86 g of styrene manufactured by Kishida Chemical, 14 g of 57% divinylbenzene manufactured by Sankyo Kasei, and 0.67 g of 75% benzoyl peroxide manufactured by Nacalai Tesque was used.
A 0.5% Kuraray PVA solution was used as the hydrophilic liquid.
As an aqueous medium, a 2% Kuraray PVA solution was used.
[0074]
The above-mentioned hydrophobic liquid and hydrophilic liquid were simultaneously sent from the inlets of the tubes A and B at a flow rate of 15 ml / h simultaneously using a cylinder pump. The hydrophobic liquid introduced from the tube A and the hydrophilic liquid introduced from the tube B merge in the flow channel structure to form a mixed solution, which is released from the tube C into the aqueous medium and comprises the hydrophobic liquid. Droplets (hydrophobic droplets) were generated. A micrograph of the obtained hydrophobic droplet was taken, and its average particle size and uniformity coefficient were determined. As a result, the average particle size was 350 μm, and the uniformity coefficient was 1.07.
[0075]
Next, the hydrophobic droplets were transferred to a 1 L reaction flask, heated to 80 ° C. under stirring and maintained for 8 hours, and the polymerization reaction was allowed to proceed to produce polymer beads. A micrograph of the obtained polymer beads was taken, and the average particle size and uniformity coefficient were determined. The average particle size was 330 μm and the uniformity factor was 1.07.
[0076]
Subsequently, 10 g of the polymer beads were placed in a four-necked flask equipped with a cooling tube together with 20 g of dichloroethane and 100 g of 98% sulfuric acid, and reacted at 100 ° C. for 4 hours with stirring. After cooling, the reaction solution was replaced with dilute sulfuric acid and then water. The resulting particles were filtered, packed in a column, passed through 30 BV of a 4% sodium chloride solution, and then passed through 30 BV of water and washed with water to obtain a Na-type cation exchange resin. A micrograph of the obtained cation exchange resin was taken, and its average particle size and uniformity coefficient were determined. The average particle size was 470 μm, and the uniformity coefficient was 1.05.
[0077]
[Comparative Example 1]
An experiment was performed in the same manner as in Example 1 except that the tube B was closed and the hydrophilic liquid was not flowed, and only the hydrophobic liquid was passed at 15 ml / h. The hydrophobic liquid released into the aqueous medium from coalescence coalesced and did not have the form of droplet particles.
[0078]
[Comparative Example 2]
A mixture of 86 g of styrene manufactured by Kishida Chemical, 14 g of 57% divinylbenzene manufactured by Sankyo Kasei, and 0.67 g of 75% benzoyl peroxide manufactured by Nacalai Tesque, and 500 ml of 0.1% Kuraray PVA solution were reacted in 1 L. The mixture was placed in a flask, heated to 80 ° C. under stirring and maintained for 8 hours, and the polymerization reaction was allowed to proceed to produce polymer beads. A micrograph of the obtained polymer beads was taken, and the average particle diameter and the uniformity coefficient were determined. The average particle diameter was 360 μm and the uniformity coefficient was 1.50.
[0079]
【The invention's effect】
According to the present invention, by using a channel structure in which a plurality of inflow paths merge to reach one outflow path, a hydrophobic liquid and a hydrophilic liquid are introduced from separate inflow paths and merged to form a uniform liquid. Since the amount of hydrophobic liquid is intermittently released into the aqueous medium, strict control of the flow rate is not required, and the generation of heat and safety issues are not accompanied by the union of liquids. Hydrophobic droplets and polymer beads with high uniformity can be stably produced on an industrial scale with simple equipment, while preventing generation of droplets having a large particle diameter in principle. Further, using the obtained polymer beads, a highly uniform ion exchange resin can be stably produced on an industrial scale.
[Brief description of the drawings]
FIG. 1 is a diagram schematically illustrating a configuration of a device for producing polymer beads according to an embodiment of the present invention.
FIGS. 2A and 2B are diagrams schematically showing an example of a configuration of a flow path in the apparatus for producing polymer beads shown in FIG. 1. FIG.
FIG. 3 is a diagram schematically illustrating a configuration of a device for producing polymer beads according to a modification of one embodiment of the present invention.
FIG. 4 is a diagram schematically illustrating a configuration of an apparatus for producing a hydrophobic liquid according to an embodiment of the present invention.
FIG. 5 is a diagram schematically illustrating a partial configuration of a device for producing polymer beads and a device for producing a hydrophobic liquid according to a modification of one embodiment of the present invention.
FIG. 6: Reference of the present invention (4 ^th Int. Conf. It is a figure for explaining on Microreaction Technology (March 2000) p133-140).

Claims (6)

In a flow channel structure in which a plurality of inflow channels merge to reach one outflow channel, a hydrophobic liquid and a hydrophilic liquid are introduced from separate inflow channels and merged in the flow channel structure to obtain a mixed liquid. By discharging the hydrophobic liquid in the mixed solution into the aqueous medium by discharging the hydrophobic liquid from the outflow path into the aqueous medium, thereby producing droplets composed of the hydrophobic liquid. Production method. The method for producing a hydrophobic droplet according to claim 1, wherein the hydrophobic liquid contains a polymerizable monomer and a polymerization initiator. In a channel structure in which a plurality of inflow channels merge to one outflow channel, a hydrophobic liquid and a hydrophilic liquid containing a polymerizable monomer are introduced from separate inflow channels and merged in the channel structure. Discharging the resulting mixed liquid into the aqueous medium from the outflow channel, and dispersing the hydrophobic liquid in the mixed liquid in the aqueous medium, thereby obtaining droplets composed of the hydrophobic liquid. A method for producing polymer beads, comprising polymerizing a polymerizable monomer in a droplet. The method according to claim 3, wherein the hydrophobic liquid further contains a polymerization initiator. A channel portion having a channel structure in which a plurality of inflow channels merge to reach one outflow channel,
Hydrophobic liquid containing a polymerizable monomer, a hydrophobic liquid introducing means for introducing into at least one inflow path of the flow path portion,
A hydrophilic liquid introducing means for introducing a hydrophilic liquid into at least one other inflow path of the flow path portion,
A hydrophobic droplet production tank that is provided on the outflow path side of the flow path section and holds an aqueous medium,
A polymerization reaction tank connected to the hydrophobic droplet production tank and polymerizing the polymerizable monomer is provided,
The hydrophobic liquid introduced by the hydrophobic liquid introduction unit and the hydrophilic liquid introduced by the hydrophilic liquid introduction unit are combined in the flow path structure of the flow path unit, and the obtained mixed liquid is mixed. By discharging the hydrophobic liquid from the outflow channel into the aqueous medium of the hydrophobic droplet production tank and dispersing the hydrophobic liquid in the mixed liquid in the aqueous medium, a droplet composed of the hydrophobic liquid is obtained. An apparatus for producing polymer beads, comprising introducing a droplet into the polymerization reaction tank and polymerizing a polymerizable monomer in the droplet. The method for producing an ion exchange resin according to claim 3 or 4, wherein an ion exchange group is introduced into the obtained polymer beads.

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