JPH07126311A - Polymerization of methyl methacrylate monomer - Google Patents
Polymerization of methyl methacrylate monomerInfo
- Publication number
- JPH07126311A JPH07126311A JP29597993A JP29597993A JPH07126311A JP H07126311 A JPH07126311 A JP H07126311A JP 29597993 A JP29597993 A JP 29597993A JP 29597993 A JP29597993 A JP 29597993A JP H07126311 A JPH07126311 A JP H07126311A
- Authority
- JP
- Japan
- Prior art keywords
- polymerization
- methyl methacrylate
- polymer
- chain transfer
- monomer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F20/00—Homopolymers and copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride, ester, amide, imide or nitrile thereof
- C08F20/02—Monocarboxylic acids having less than ten carbon atoms, Derivatives thereof
- C08F20/10—Esters
- C08F20/12—Esters of monohydric alcohols or phenols
- C08F20/14—Methyl esters, e.g. methyl (meth)acrylate
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Polymerisation Methods In General (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明はメチルメタクリレート単
量体の重合方法に関する。FIELD OF THE INVENTION The present invention relates to a method for polymerizing a methyl methacrylate monomer.
【０００２】[0002]
【従来の技術】従来、メチルメタクリレート単量体（Ｍ
ＭＡ）を重合させる際に、ポリマーの分子量を調節する
目的で連鎖移動剤を用いることは知られている。連鎖移
動剤としては、特公昭５８−４５５号公報に、ｎ−ドデ
シルメルカプタン等のアルキルメルカプタンが開示され
ている。又近畿大学工学部研究報告第１６巻１９頁（１
９８２）には、ターピノーレン等のテルペノイドを添加
することにより得られた重合物の分子量は低いことが開
示されている。更に、四塩化炭素等のハロゲン化アルキ
ルや２，４−ジフェニル−４−メチル−１−ペンテン
（ＭＳＤ）等が知られている。2. Description of the Related Art Conventionally, a methyl methacrylate monomer (M
When polymerizing MA), it is known to use a chain transfer agent for the purpose of controlling the molecular weight of the polymer. As a chain transfer agent, Japanese Patent Publication No. 58-455 discloses alkyl mercaptans such as n-dodecyl mercaptan. Kinki University Faculty of Engineering, Research Report, Vol. 16, p. 19 (1
982) discloses that the molecular weight of a polymer obtained by adding a terpenoid such as terpinolene is low. Furthermore, alkyl halides such as carbon tetrachloride and 2,4-diphenyl-4-methyl-1-pentene (MSD) are known.
【０００３】[0003]
【発明が解決しようとする課題】上記連鎖移動剤の内、
メルカプタン類はその取り扱いにおいて臭気が発生し、
又重合物に臭気が残存し且つ重合物を着色させるという
問題がある。又ハロゲン化アルキル類は環境汚染の問題
がある。又テルペン類及びＭＳＤは退化的連鎖移動によ
り重合速度が低下し残存モノマーが増加するという問題
がある。Of the above chain transfer agents,
The mercaptans generate an odor when handled,
Further, there is a problem that odor remains in the polymer and the polymer is colored. Also, alkyl halides pose a problem of environmental pollution. In addition, terpenes and MSD have a problem that the polymerization rate decreases due to degenerative chain transfer and the residual monomer increases.
【０００４】[0004]
【課題を解決するための手段】本発明者らは、上記従来
法の問題点を長期にわたって研究した結果、特定の化合
物を連鎖移動剤として用いることによって、それらの問
題点をすべて解決したＭＭＡの重合方法を見いだし、本
発明を完成するに至った。即ち、本発明は、メチルメタ
クリレート単量体をラジカル重合開始剤を用いて重合又
は他のビニル重合体と共重合させる際に、連鎖移動剤と
してジメチル−２，２−ジメチル−４−メチレン−グル
タレートの存在下で重合を行うことを特徴とするメチル
メタクリレート単量体の重合方法に関する。DISCLOSURE OF THE INVENTION The present inventors have studied the problems of the above-mentioned conventional method for a long time, and as a result, by using a specific compound as a chain transfer agent, MMA has been solved. The polymerization method was found and the present invention was completed. That is, the present invention relates to dimethyl-2,2-dimethyl-4-methylene-glutarate as a chain transfer agent when a methyl methacrylate monomer is polymerized using a radical polymerization initiator or is copolymerized with another vinyl polymer. The present invention relates to a method for polymerizing a methyl methacrylate monomer, wherein the polymerization is carried out in the presence of
【０００５】本発明において、ＭＭＡと共重合可能なビ
ニル単量体としては、具体的には例えばスチレン；アク
リロニトリル；酢酸ビニル；メタクリル酸及びエチルメ
タクリレート、ブチルメタクリレート、２−ヒドロキシ
エチルメタクリレート等のメタクリレート類；アクリル
酸及びメチルアクリレート、ブチルアクリレート、２−
ヒドロキシエチルアクリレート等のアクリレート類など
を挙げることができる。In the present invention, as the vinyl monomer copolymerizable with MMA, specifically, for example, styrene; acrylonitrile; vinyl acetate; methacrylic acid and methacrylates such as ethyl methacrylate, butyl methacrylate and 2-hydroxyethyl methacrylate. Acrylic acid and methyl acrylate, butyl acrylate, 2-
Examples thereof include acrylates such as hydroxyethyl acrylate.
【０００６】ジメチル−２，２−ジメチル−４−メチレ
ン−グルタレート（以下ＭＭＡダイマーと略記する）は
米国特許第４５４７３２３号明細書に記載された方法に
より製造することができる。Dimethyl-2,2-dimethyl-4-methylene-glutarate (hereinafter abbreviated as MMA dimer) can be produced by the method described in US Pat. No. 4,547,323.
【０００７】ＭＭＡの重合又は共重合に際して存在させ
るＭＭＡダイマーは、一般にＭＭＡ１００重量部に対し
て０．０１重量部〜５重量部、好ましくは０．１重量部
〜３重量部である。０．０１重量部未満では分子量調節
の効果が小さく、又５重量部を超えて用いると重合物の
機械強度を低下させるため夫々好ましくない。The MMA dimer which is present during the polymerization or copolymerization of MMA is generally 0.01 to 5 parts by weight, preferably 0.1 to 3 parts by weight, based on 100 parts by weight of MMA. If it is less than 0.01 part by weight, the effect of controlling the molecular weight is small, and if it is used in excess of 5 parts by weight, the mechanical strength of the polymer is lowered, which is not preferable.
【０００８】本発明において、用いられる重合開始剤と
しては、ｔ−ブチルペルオキシネオデカノエート、ｔ−
ヘキシルペルオキシネオデカノエート、ｔ−ブチルペル
オキシネオヘキサノエート、ｔ−ヘキシルペルオキシネ
オヘキサノエート、ｔ−ブチルペルオキシピバレート、
ｔ−ヘキシルペルオキシピバレート、ベンゾイルペルオ
キシド、ラウロイルペルオキシド、ｔ−ブチルペルオキ
シ−２−エチルヘキサノエート、ｔ−ヘキシルペルオキ
シ−２−エチルヘキサノエート、ｔ−ブチルヒドロペル
オキシド、パラメンタンヒドロペルオキシド、クメンヒ
ドロペルオキシド等の有機過酸化物、アゾビスイソブチ
ロニトリル等のアゾ化合物、過硫酸アンモン等の過硫酸
塩が挙げられる。In the present invention, the polymerization initiator used is t-butylperoxyneodecanoate, t-butylperoxyneodecanoate.
Hexyl peroxy neodecanoate, t-butyl peroxy neohexanoate, t-hexyl peroxy neohexanoate, t-butyl peroxypivalate,
t-hexyl peroxypivalate, benzoyl peroxide, lauroyl peroxide, t-butylperoxy-2-ethylhexanoate, t-hexylperoxy-2-ethylhexanoate, t-butylhydroperoxide, paramenthane hydroperoxide, cumene hydro Examples thereof include organic peroxides such as peroxides, azo compounds such as azobisisobutyronitrile, and persulfates such as ammonium persulfate.
【０００９】本発明に用いられる重合方法としては、例
えば注型重合、懸濁重合、溶液重合、乳化重合等があ
り、更にはそれらを組合せて用いることもできる。The polymerization method used in the present invention includes, for example, cast polymerization, suspension polymerization, solution polymerization, emulsion polymerization and the like, and they may be used in combination.
【００１０】本発明における重合温度は、用いる重合開
始剤の種類により異なるが一般に０℃〜１５０℃、好ま
しくは４０℃〜１３０℃が用いられる。０℃未満では重
合速度が遅くなり、又１５０℃を超える温度では重合速
度が大きくなり過ぎて速度の制御が困難になりいずれも
好ましくない。又重合温度は、上記の温度範囲において
一定あるいは段階的、逐次的に昇温させる方法等いずれ
でもよく、特に限定されない。The polymerization temperature in the present invention is generally 0 ° C to 150 ° C, preferably 40 ° C to 130 ° C, although it varies depending on the kind of the polymerization initiator used. If the temperature is lower than 0 ° C, the polymerization rate becomes slow, and if the temperature exceeds 150 ° C, the polymerization rate becomes too high and the rate control becomes difficult. The polymerization temperature may be constant, stepwise or stepwise in the above temperature range, and is not particularly limited.
【００１１】[0011]
【発明の効果】本発明の重合方法により臭気がなく、環
境汚染がなく、重合速度の低下による残存モノマーが少
なく且つ着色が少ないメチルメタクリレートの重合体又
は共重合体を得ることができる。Industrial Applicability According to the polymerization method of the present invention, a methyl methacrylate polymer or copolymer having no odor, no environmental pollution, less residual monomer and less coloring due to a decrease in polymerization rate can be obtained.
【００１２】[0012]
【実施例】以下、実施例及び比較例により本発明を具体
的に説明する。EXAMPLES The present invention will be specifically described below with reference to Examples and Comparative Examples.
【００１３】実施例 １ 粘度が２０℃で１０ポイズで濃度２０％のＭＭＡシロッ
プ５００ｇにアクリル酸メチル５ｇ、ＭＭＡダイマー１
０ｇ、ｔ−ヘキシルペルオキシピバレート（日本油脂
（株）製、商品名パーヘキシルＰＶ、純度７０％）１．
５ｇ及び少量の離型剤を添加し、溶解した後真空脱気し
た。これを２枚のガラス板とポリ塩化ビニルのガスケッ
トで作られたキャスト用セルに注入し、７０℃の水浴中
で８時間硬化後、更に１２０℃の空気浴で２時間重合さ
せ、厚さ２００×１００×３ｍｍの板を得た。得られた
板を一部切り出して、ベンゼンに溶解しガスクロマトグ
ラフ（ＧＬＣ）により、残存モノマーを定量した結果、
１．８％であった。またＧＰＣによる重量平均分子量は
２６００００であった。次いで得られた板の側面を研磨
し、板の着色度を調べた結果殆ど無色であった。又板の
破砕物には異臭が認められなかった。Example 1 500 g of MMA syrup having a viscosity of 20 poise at 20 ° C. and a concentration of 20%, 5 g of methyl acrylate and 1 of MMA dimer
0 g, t-hexyl peroxypivalate (manufactured by NOF CORPORATION, trade name Perhexyl PV, purity 70%)
5 g and a small amount of release agent were added, dissolved and then vacuum degassed. This was poured into a casting cell made of two glass plates and a polyvinyl chloride gasket, cured in a water bath at 70 ° C for 8 hours, and then polymerized in an air bath at 120 ° C for 2 hours to give a thickness of 200. A plate of × 100 × 3 mm was obtained. A part of the obtained plate was cut out, dissolved in benzene, and the result of quantifying the residual monomer by gas chromatography (GLC),
It was 1.8%. The weight average molecular weight by GPC was 260,000. Then, the side surface of the obtained plate was polished, and the degree of coloring of the plate was examined. As a result, it was almost colorless. No offensive odor was observed in the crushed product of the plate.
【００１４】比較例 １ 実施例１においてＭＭＡダイマーを用いる代わりに、タ
ーピノーレン（日本油脂（株）製、商品名ノフマーＴ
Ｐ、純度９４％）１０ｇを用いた他は実施例１に準じて
処理した。その結果、板は無色であり、板の破砕物には
異臭が認められなかったが、残存モノマーは３．９％で
あった。又重量平均分子量は２７００００であった。実
施例１及び比較例１の結果から本発明の方法は、従来知
られている無臭タイプの連鎖移動剤と比較すると得られ
た重合体の残存モノマーが少ないことが判る。Comparative Example 1 Instead of using the MMA dimer in Example 1, terpinolene (trade name NOFMER T manufactured by NOF CORPORATION)
P, purity 94%) was used, and the same procedure as in Example 1 was performed. As a result, the plate was colorless and no odor was observed in the crushed product of the plate, but the residual monomer content was 3.9%. The weight average molecular weight was 270000. From the results of Example 1 and Comparative Example 1, it can be seen that the method of the present invention has less residual monomer in the polymer obtained as compared with the conventionally known odorless type chain transfer agent.
【００１５】比較例 ２ 実施例１においてＭＭＡダイマーを用いる代わりに、ｎ
−ドデシルメルカプタン０．５ｇを用いた他は実施例１
に準じて処理した。その結果、残存モノマーは１．３％
であり、又重量平均分子量は２６００００であった。然
し得られた板の側面は淡黄色であり、板の破砕物にはメ
ルカプタン臭が認められた。実施例１及び比較例２の結
果から本発明の方法は従来知られている硫黄系連鎖移動
剤を用いた時と比較すると得られた重合体には臭気がな
く、着色が少ないことが判る。Comparative Example 2 Instead of using the MMA dimer in Example 1, n
Example 1 except 0.5 g of dodecyl mercaptan was used
Processed according to. As a result, residual monomer is 1.3%
And the weight average molecular weight was 260,000. However, the side surface of the obtained plate was pale yellow, and the crushed product of the plate had a mercaptan odor. From the results of Example 1 and Comparative Example 2, it can be seen that the method of the present invention has no odor and little coloring in the obtained polymer as compared with the case of using the conventionally known sulfur chain transfer agent.
【００１６】実施例 ２ 容量５０００ｍｌのオートクレーブにＭＭＡ２０００
ｇ、ＭＭＡダイマー６０ｇ、ｔ−ブチルペルオキシネオ
デカノエート（日本油脂（株）製、商品名パーブチルＮ
Ｄ、純度９０％）１０ｇ、ｔ−ブチルペルオキシ−２−
エチルヘキサノエート（日本油脂（株）製、商品名パー
ブチルＯ、純度９０％）５ｇ、イオン交換水２０００
ｇ、ドデシルベンゼンスルホン酸ソーダ（日本油脂
（株）製、商品名ニューレックスＲ）０．２ｇ及び第三
燐酸カルシウム１０ｇを仕込み、窒素置換した後５５℃
で５時間、次いで５５℃から９０℃まで毎時１０℃の割
合で昇温しながら３．５時間重合した。その後重合物を
塩酸洗浄と水洗し乾燥し粉状重合物を得た。重合物をＧ
ＬＣ分析した結果、残存モノマーは１．６％であり又Ｇ
ＰＣによる分子量は１７００００であった。又重合物に
異臭は認められなかった。又重合物を加圧成形し、１０
０×１００×３ｍｍの板を得た。この板の側面を研磨し
て板の着色度を調べた結果、殆ど無色であった。Example 2 MMA2000 was placed in an autoclave having a volume of 5000 ml.
g, MMA dimer 60 g, t-butyl peroxy neodecanoate (manufactured by NOF CORPORATION, trade name Perbutyl N)
D, purity 90%) 10 g, t-butylperoxy-2-
5 g of ethyl hexanoate (manufactured by NOF CORPORATION, trade name Perbutyl O, purity 90%), ion-exchanged water 2000
g, sodium dodecylbenzene sulfonate (Nippon Yushi Co., Ltd., trade name Nurex R) 0.2 g and tricalcium phosphate 10 g were charged, and after nitrogen substitution, 55 ° C.
For 5 hours and then for 3.5 hours while raising the temperature from 55 ° C. to 90 ° C. at a rate of 10 ° C./hour. Thereafter, the polymer was washed with hydrochloric acid, washed with water and dried to obtain a powdery polymer. Polymer G
As a result of LC analysis, the residual monomer was 1.6% and G
The molecular weight by PC was 170000. No off-flavor was observed in the polymer. In addition, the polymer is pressure-molded to produce 10
A plate of 0x100x3 mm was obtained. As a result of polishing the side surface of this plate and examining the degree of coloring of the plate, it was found to be almost colorless.
【００１７】比較例 ３ 公知の無臭タイプの連鎖移動剤を用いて実施例２で得ら
れた重合体と同様の重量平均分子量１７００００の重合
体を得るようにＭＭＡダイマーの代わりに、２，４−ジ
フェニル−４−メチル−１−ペンテン（日本油脂（株）
製、商品名ノフマーＭＳＤ、純度９５％）８ｇを用いた
他は実施例２に準じて処理した。その結果、残存モノマ
ーは２．３％であった。実施例２及び比較例３の結果か
ら本発明方法は、従来知られている無臭タイプの連鎖移
動剤を重量平均分子量を一致させる量用いたときと比較
して残存モノマーが少ないことが判る。COMPARATIVE EXAMPLE 3 A known odorless type chain transfer agent was used instead of the MMA dimer so as to obtain a polymer having a weight average molecular weight of 170000 similar to the polymer obtained in Example 2, 2,4-. Diphenyl-4-methyl-1-pentene (NOF CORPORATION)
(Manufactured by Nofmer MSD, purity 95%) 8 g was used, and treated according to Example 2. As a result, the residual monomer content was 2.3%. From the results of Example 2 and Comparative Example 3, it is understood that the method of the present invention has less residual monomer than the conventionally known odorless type chain transfer agent when used in an amount that matches the weight average molecular weight.
【００１８】比較例 ４ 実施例２においてＭＭＡダイマーを用いる代わりに、ｎ
−ドデシルメルカプタン０．４ｇを用いた他は実施例２
に準じて処理して重量平均分子量が実施例２と同様に１
７００００である重合体を得た。重合体の残存モノマー
は１．７％であった。得られた板の側面は淡黄色であっ
た。又得られた板を破砕したものはメルカプタン臭が認
められた。実施例２及び比較例４の結果から懸濁重合に
おいても、本発明の方法は従来知られている硫黄系連鎖
移動剤を用いた時と比較して臭気がなく、着色が少ない
ことが判る。Comparative Example 4 Instead of using the MMA dimer in Example 2, n
Example 2 except that 0.4 g of dodecyl mercaptan was used
And the weight average molecular weight was 1 as in Example 2.
A polymer of 70,000 was obtained. The residual monomer content of the polymer was 1.7%. The side surface of the obtained plate was pale yellow. The crushed plate obtained had a mercaptan odor. From the results of Example 2 and Comparative Example 4, it can be seen that also in suspension polymerization, the method of the present invention has no odor and produces less coloring than when the conventionally known sulfur-based chain transfer agent is used.
Claims (1)
重合開始剤を用いて重合又は他のビニル単量体と共重合
させる際に、連鎖移動剤としてジメチル−２，２−ジメ
チル−４−メチレン−グルタレートの存在下で重合を行
うことを特徴とするメチルメタクリレート単量体の重合
方法。1. A dimethyl-2,2-dimethyl-4-methylene-glutarate as a chain transfer agent when a methyl methacrylate monomer is polymerized using a radical polymerization initiator or is copolymerized with another vinyl monomer. A method for polymerizing a methyl methacrylate monomer, wherein the polymerization is performed in the presence of
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29597993A JPH07126311A (en) | 1993-11-02 | 1993-11-02 | Polymerization of methyl methacrylate monomer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29597993A JPH07126311A (en) | 1993-11-02 | 1993-11-02 | Polymerization of methyl methacrylate monomer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH07126311A true JPH07126311A (en) | 1995-05-16 |
Family
ID=17827572
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP29597993A Pending JPH07126311A (en) | 1993-11-02 | 1993-11-02 | Polymerization of methyl methacrylate monomer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07126311A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007131838A (en) * | 2005-10-11 | 2007-05-31 | Sekisui Chem Co Ltd | Method for producing acrylic polymer, the resultant acrylic polymer, acrylic adhesive composition, and adhesive tape |
| JP2008138034A (en) * | 2006-11-30 | 2008-06-19 | Soken Chem & Eng Co Ltd | Method for producing eco-friendly adhesive |
-
1993
- 1993-11-02 JP JP29597993A patent/JPH07126311A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007131838A (en) * | 2005-10-11 | 2007-05-31 | Sekisui Chem Co Ltd | Method for producing acrylic polymer, the resultant acrylic polymer, acrylic adhesive composition, and adhesive tape |
| JP2008138034A (en) * | 2006-11-30 | 2008-06-19 | Soken Chem & Eng Co Ltd | Method for producing eco-friendly adhesive |
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