JP3197947B2 - Method for preventing polymerization of (meth) acrylic acid - Google Patents
Method for preventing polymerization of (meth) acrylic acidInfo
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- JP3197947B2 JP3197947B2 JP15451892A JP15451892A JP3197947B2 JP 3197947 B2 JP3197947 B2 JP 3197947B2 JP 15451892 A JP15451892 A JP 15451892A JP 15451892 A JP15451892 A JP 15451892A JP 3197947 B2 JP3197947 B2 JP 3197947B2
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- Prior art keywords
- acrylic acid
- meth
- oxyl
- polymerization
- acid
- 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.)
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Description
【0001】[0001]
【産業上の利用分野】本発明は(メタ)アクリル酸の重
合防止方法に関するものである。更に詳しくはアクリル
酸またはメタクリル酸の精製、貯蔵もしくは輸送中また
はエステル化反応時に、重合防止剤として、酸性条件下
でFe(III)との錯体の安定度定数が10以上のキレー
ト化剤と、N−オキシル化合物を共存させることを特徴
とする重合防止方法に関するものである。The present invention relates to a method for preventing polymerization of (meth) acrylic acid. More specifically, a chelating agent having a stability constant of a complex with Fe (III) under acidic conditions of 10 or more as a polymerization inhibitor during purification, storage or transportation of acrylic acid or methacrylic acid or during an esterification reaction; The present invention relates to a method for preventing polymerization, which comprises coexisting an N-oxyl compound.
【0002】[0002]
【従来の技術】(メタ)アクリル酸は、極めて重合しや
すく、製造工程、貯蔵もしくは輸送中またはエステル化
反応に使用する際に、熱、光、その他の要因によりしば
しば重合トラブルを起こすことが知られている。2. Description of the Related Art It is known that (meth) acrylic acid is extremely liable to polymerize and frequently causes polymerization troubles due to heat, light and other factors during the production process, during storage or transportation, or when used in an esterification reaction. Have been.
【0003】従来から、(メタ)アクリル酸用の重合抑
制剤として、フェノチアジン、フェニレンジアミン等の
芳香族アミン類、ハイドロキノン及びその誘導体等のフ
ェノール類化合物が知られている。Hitherto, as polymerization inhibitors for (meth) acrylic acid, aromatic amines such as phenothiazine and phenylenediamine, and phenol compounds such as hydroquinone and its derivatives have been known.
【0004】[0004]
【発明が解決しようとする課題】しかしながら、これら
の化合物は重合抑制剤としての能力が不十分であった
り、高価である等の問題を有していた。さらに(メタ)
アクリル酸のモノマーとしての貯蔵安定性を確保するた
め多量に添加した場合には、着色の原因になったり、ま
た蒸留操作によってのみ、重合抑制剤の除去が可能であ
り、その除去は容易でなかった。However, these compounds have problems such as insufficient ability as a polymerization inhibitor or being expensive. Furthermore (meta)
If acrylic acid is added in a large amount in order to ensure storage stability as a monomer, it may cause coloration, or the polymerization inhibitor can be removed only by distillation, and the removal is not easy. Was.
【0005】本発明者らは、前記の問題点を克服すべ
く、鋭意検討した結果、本発明に到達した。[0005] The present inventors have conducted intensive studies to overcome the above-mentioned problems, and as a result, have reached the present invention.
【0006】[0006]
【課題を解決するための手段】本発明者らは(メタ)ア
クリル酸の重合原因について詳細に解析したところ、多
くの場合、(メタ)アクリル酸中に極く微量存在する鉄
イオン(Fe(III))により重合が起こることを見いだ
した。この鉄イオン濃度は数ppb 以下の、極く微少量で
あるにも拘らず、(メタ)アクリル酸と特殊な錯体を形
成して、重合に至る事が判明した。最近の分析技術の進
歩によってはじめて測定可能となった、この極く微少量
の鉄イオンの混入は避けられず、また除去する事も容易
ではない。The present inventors have analyzed the cause of polymerization of (meth) acrylic acid in detail. In many cases, the present inventors have found that a very small amount of iron ion (Fe ( III)) was found to cause polymerization. Although this iron ion concentration was extremely small, less than several ppb, it was found that a special complex was formed with (meth) acrylic acid, leading to polymerization. This very small amount of iron ion contamination, which has become measurable for the first time due to recent advances in analytical techniques, is inevitable and it is not easy to remove it.
【0007】そこで本発明者らは重合起因となる鉄錯体
を分解する物質について鋭意検討した結果、酸性条件下
でFe(III)との錯体の安定度定数が10以上のキレー
ト化剤のみが、その効果を有する事を見いだし、先に、
酸性条件下でFe(III)との錯体の安定度定数が10以
上のキレート化剤と、フェノチアジン、芳香族アミン
類、フェノール類化合物を共存させる(メタ)アクリル
酸の重合防止方法を提案した。The inventors of the present invention have conducted intensive studies on substances that decompose an iron complex that causes polymerization, and as a result, it has been found that only a chelating agent having a stability constant of 10 or more with Fe (III) under acidic conditions is obtained. I found that it had the effect,
A method for preventing polymerization of (meth) acrylic acid in which a chelating agent having a stability constant of a complex with Fe (III) under acidic conditions of 10 or more and phenothiazine, aromatic amines and phenol compounds coexist is proposed.
【0008】その後さらに鋭意検討を重ねた結果、酸性
条件下におけるFe(III)との錯体の安定度定数が10
以上のキレート化剤と、2,2,6,6−テトラメチル
ピペリジン基を有するN−オキシル化合物を共存させる
ことにより、(メタ)アクリル酸の予期せぬ重合抑制効
果を有することを見出だし、本発明を完成するに至っ
た。After further intensive studies, the stability constant of the complex with Fe (III) under acidic conditions was 10
By coexisting the above chelating agent and an N-oxyl compound having a 2,2,6,6-tetramethylpiperidine group, it has been found that the compound has an unexpected polymerization inhibitory effect of (meth) acrylic acid, The present invention has been completed.
【0009】即ち、本発明は、(メタ)アクリル酸の精
製時、貯蔵もしくは輸送時またはエステル化反応時に、
重合防止剤として、酸性条件下におけるFe(III)との
錯体の安定度定数が10以上のキレート化剤と、下記一
般式(1)で表されるN−オキシル化合物を共存させる
ことを特徴とする(メタ)アクリル酸の重合防止方法に
関するものである。That is, the present invention provides a method for purifying (meth) acrylic acid, storing or transporting, or performing an esterification reaction.
As a polymerization inhibitor, a chelating agent having a stability constant of a complex with Fe (III) under acidic conditions of 10 or more and an N-oxyl compound represented by the following general formula (1) coexist. The present invention relates to a method for preventing polymerization of (meth) acrylic acid.
【化2】 ただし一般式(1)において、Rは水素原子、アルキル
基、アシル基を示す。Embedded image However, in the general formula (1), R represents a hydrogen atom, an alkyl group, or an acyl group.
【0010】本発明に用いられる(メタ)アクリル酸と
は、アクリル酸またはメタクリル酸であり、どのような
製法により製造された(メタ)アクリル酸にも用いるこ
とができる。The (meth) acrylic acid used in the present invention is acrylic acid or methacrylic acid, and can be used for (meth) acrylic acid produced by any production method.
【0011】錯体の酸性条件下での安定度定数について
は、例えば上野景平著作「キレート滴定法」(南江堂発
行)に詳しい記述があるが、本発明で使用される、酸性
条件下で安定度定数10以上のキレート化剤として、具
体的には、エチレンジアミン四酢酸(EDTA)、トラ
ンス−1,2−シクロヘキサンジアミン四酢酸(CyD
TA)、ジエチレントリアミン五酢酸(DTPA)があ
る。これらのキレート化剤はそのまま、または調製時の
溶解性を考慮してナトリウム塩、カリウム塩、リチウム
塩等のアルカリ金属塩として用いることができる。この
使用量は、特に制限はないが、(メタ)アクリル酸モノ
マーにたいして0.00001〜0.001重量%と微
少量で著しい効果を発揮する。キレート化剤と共存させ
るN−オキシル化合物は、下記一般式(1)で表される
ものが使用される。The stability constant of the complex under acidic conditions is described in detail in, for example, "Chelate Titration Method" (published by Nankodo) written by Keihei Ueno. As a chelating agent having a constant of 10 or more, specifically, ethylenediaminetetraacetic acid (EDTA), trans-1,2-cyclohexanediaminetetraacetic acid (CyD
TA), diethylenetriaminepentaacetic acid (DTPA). These chelating agents can be used as they are or as alkali metal salts such as sodium salts, potassium salts and lithium salts in consideration of solubility during preparation. The amount of use is not particularly limited, but a very small amount of 0.00001 to 0.001% by weight with respect to the (meth) acrylic acid monomer exhibits a remarkable effect. As the N-oxyl compound coexisting with the chelating agent, one represented by the following general formula (1) is used.
【化3】 ただし一般式(1)において、Rは水素原子、アルキル
基、アシル基を示す。そのうち適切なものは、Rが水素
原子、炭素数1〜6のアルキル基、炭素数1〜8のアシ
ル基を有する化合物であり、特に2,2,6,6−テト
ラメチル−4−アセトキシピペリジン−1−オキシル、
2,2,6,6−テトラメチル−4−ヒドロキシピペリ
ジン−1−オキシルまたは2,2,6,6−テトラメチ
ル−4−メトキシピペリジン−1−オキシル等が望まし
く、その使用量は(メタ)アクリル酸モノマ−に対して
0.0001〜0.05重量%、好ましくは0.000
1〜0.01重量%である。Embedded image However, in the general formula (1), R represents a hydrogen atom, an alkyl group, or an acyl group. Among them, suitable are compounds in which R has a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and an acyl group having 1 to 8 carbon atoms, and particularly, 2,2,6,6-tetramethyl-4-acetoxypiperidine. -1-oxyl,
Desirable are 2,2,6,6-tetramethyl-4-hydroxypiperidine-1-oxyl and 2,2,6,6-tetramethyl-4-methoxypiperidine-1-oxyl. 0.0001 to 0.05% by weight, preferably 0.000% by weight, based on the acrylic acid monomer
1 to 0.01% by weight.
【0012】この重合防止剤は、(メタ)アクリル酸と
メタノール、エタノール、ブタノール、2−エチルヘキ
サノール、エチレンオキサイド、ステアリルアルコー
ル、トリブチル錫オキサイド等との反応にも使用され
る。その際、触媒として硫酸、p−トルエンスルホン
酸、陽イオン交換樹脂等が使用されるが特に制限はな
い。This polymerization inhibitor is also used in the reaction of (meth) acrylic acid with methanol, ethanol, butanol, 2-ethylhexanol, ethylene oxide, stearyl alcohol, tributyltin oxide and the like. At this time, sulfuric acid, p-toluenesulfonic acid, a cation exchange resin or the like is used as a catalyst, but there is no particular limitation.
【0013】また、本発明の使用雰囲気は、窒素等の不
活性ガス下でも有効であるが、(メタ)アクリル酸の精
製時およびエステル反応使用時においては、酸素の存在
下で使用する方が有効である。この場合の酸素の供給方
法としては、空気バブリング方式が具体例として挙げら
れる。Although the use atmosphere of the present invention is effective even under an inert gas such as nitrogen, it is more preferable to use it in the presence of oxygen when purifying (meth) acrylic acid and when using an ester reaction. It is valid. A specific example of the oxygen supply method in this case is an air bubbling method.
【0014】さらに、実施例で示すように、本発明の重
合防止能力は、従来のものより格段に優れており、使用
する場合もその添加量を大幅に削減することが可能とな
る。それ故、着色も少なくなり、特に貯蔵安定剤として
用いる場合には、除去操作も必要としない。Further, as shown in the examples, the polymerization inhibiting ability of the present invention is remarkably superior to that of the conventional one, and when used, the amount of addition can be greatly reduced. Therefore, coloring is reduced, and no removal operation is required, particularly when used as a storage stabilizer.
【0015】また、本発明で使用するキレート化剤は、
既知物質で毒性も低く、重金属を含有しない化合物であ
るため、環境汚染の問題もない。The chelating agent used in the present invention comprises:
It is a known substance with low toxicity and does not contain heavy metals, so there is no problem of environmental pollution.
【0016】本発明を実施する事により、従来技術の欠
点を解決する事が可能となり、その工業的意義は極めて
大きいものと思われる。By practicing the present invention, the disadvantages of the prior art can be solved, and its industrial significance is considered to be extremely large.
【0017】[0017]
【実施例】次に実施例により、具体的に説明するが、こ
れらは、本発明を限定するものではない。なお、以下の
例において、%、ppm 、ppb はいずれも重量%、重量pp
m、重量ppb を示すものである。Next, the present invention will be described in detail with reference to examples, but these examples do not limit the present invention. In the following examples,%, ppm, and ppb are weight%, weight pp
m and weight ppb.
【0018】(実験手法) 重合誘導期(IP)の測定;重合防止剤の効果を判定す
るために、(メタ)アクリル酸モノマーが重合に至まで
の誘導期の測定を行った。すなわち所定量の添加物を含
有する(メタ)アクリル酸を調製し、その5mlを試験官
に採り、シリコンゴム栓で密封した後、アクリル酸の場
合、100℃、メタクリル酸の場合、110℃の油浴中
に浸し、重合開始に伴って当該サンプルに濁りが発生す
るまでの時間を測定する。こうして得られた重合に至る
までの誘導期をIP−100(アクリル酸の場合)、ま
たはIP−110(メタクリル酸の場合)と略記して、
時間の単位で表わした。(Experimental method) Measurement of polymerization induction period (IP): In order to determine the effect of the polymerization inhibitor, the induction period until the (meth) acrylic acid monomer reached polymerization was measured. That is, (meth) acrylic acid containing a predetermined amount of an additive is prepared, and 5 ml thereof is taken to a tester, sealed with a silicone rubber stopper, and then heated to 100 ° C. for acrylic acid and 110 ° C. for methacrylic acid. The sample is immersed in an oil bath, and the time required for the sample to become cloudy with the start of polymerization is measured. The induction period leading to the polymerization thus obtained is abbreviated as IP-100 (for acrylic acid) or IP-110 (for methacrylic acid),
Expressed in units of time.
【0019】(実施例1)メタクリル酸に、pH3におけ
るFe(III)との錯体の安定度定数が12.3であるE
DTAの2カリウム塩(EDTA−2K)1.0ppm
と、2,2,6,6−テトラメチル−4−アセトキシピ
ペリジン−1−オキシル10ppm を添加してIP−11
0を測定した結果、25.0時間であった。なおこのメ
タクリル酸を一度焼却処理した後、1N硝酸溶液とし
て、フレームレス法原子吸光光度法で鉄イオン濃度を測
定すると、3ppbであった。(Example 1) The stability constant of a complex of methacrylic acid and Fe (III) at pH 3 was 12.3.
1.0 ppm of DTA dipotassium salt (EDTA-2K)
And 10 ppm of 2,2,6,6-tetramethyl-4-acetoxypiperidine-1-oxyl to add IP-11.
As a result of measuring 0, it was 25.0 hours. After the methacrylic acid was once incinerated, the iron ion concentration was measured by a flameless atomic absorption spectrometry as a 1N nitric acid solution to be 3 ppb.
【0020】(比較例1)実施例1で使用したメタクリ
ル酸にEDTA−2K 1.0ppm のみを添加した場合
のIP−110は0.1時間であった。Comparative Example 1 When only 1.0 ppm of EDTA-2K was added to the methacrylic acid used in Example 1, the IP-110 was 0.1 hour.
【0021】(比較例2)実施例1で使用したメタクリ
ル酸に2,2,6,6−テトラメチル−4−アセトキシ
ピペリジン−1−オキシル 10ppm のみを添加した場
合のIP−110は1.8時間であったComparative Example 2 The IP-110 obtained by adding only 10 ppm of 2,2,6,6-tetramethyl-4-acetoxypiperidine-1-oxyl to the methacrylic acid used in Example 1 was 1.8. Was time
【0022】(実施例2)実施例1と同様にして測定し
た結果、0.2ppm の鉄を含有するメタクリル酸にED
TA−2Kを2.0ppm 添加し、2,2,6,6−テト
ラメチル−4−アセトキシピペリジン−1−オキシル
10ppm を添加して、IP−110を測定した。その結
果22.5時間であった。(Example 2) As a result of measurement in the same manner as in Example 1, methacrylic acid containing 0.2 ppm of iron was added to ED.
2.0 ppm of TA-2K was added, and 2,2,6,6-tetramethyl-4-acetoxypiperidine-1-oxyl was added.
IP-110 was measured after adding 10 ppm. The result was 22.5 hours.
【0023】(比較例3)実施例2と同様に、EDTA
−2Kのみを添加しないでIP−110を測定すると、
0.5時間であった。Comparative Example 3 As in Example 2, EDTA
When IP-110 is measured without adding only -2K,
0.5 hours.
【0024】(実施例3〜7)実施例1と同じメタクリ
ル酸を用いて(表1)に示す重合防止剤を添加した時の
IP−110を測定した。結果を(表1)にまとめて示
す。なおpH3におけるFe(III)との錯体の安定度定数
は、CyDTAで14.5、DTPAで10.5であ
る。(Examples 3 to 7) Using the same methacrylic acid as in Example 1, IP-110 was measured when the polymerization inhibitors shown in (Table 1) were added. The results are summarized in (Table 1). The stability constant of the complex with Fe (III) at pH 3 is 14.5 for CyDTA and 10.5 for DTPA.
【0025】 (表1) 実施例 キレ−ト化剤 N−オキシル化合物 IP−110 (ppm) (ppm) (hrs) 3 EDTA−2Na R=H 11.5 0.5 5 4 DTPA R=CH3 25.6 1.0 15 5 EDTA−2Na R=COCH3 18.8 1.0 5 6 EDTA−2Li R=COPh 10.9 0.5 20 7 CyDTA−2K R=C2 H5 8.1 0.5 15(Table 1) Example Chelating agent N-oxyl compound IP-110 (ppm) (ppm) (hrs) 3 EDTA-2Na R = H 11.5 0.554 DTPA R = CH 3 25.6 1.0 155 EDTA-2Na R = COCH 3 18.8 1.056 EDTA-2Li R = COPh 10.9 0.5 207 CyDTA-2K R = C 2 H 5 8.10 .5 15
【0026】(実施例8)アクリル酸に、N−オキシル
化合物として2,2,6,6−テトラメチル−4−アセ
トキシピペリジン−1−オキシルを10ppm さらにED
TA−2Naを1ppm 添加して、IP−100を測定し
た。その結果14.7時間であった。Example 8 Acrylic acid was added with 2,2,6,6-tetramethyl-4-acetoxypiperidine-1-oxyl as an N-oxyl compound at 10 ppm.
IP-100 was measured after adding 1 ppm of TA-2Na. The result was 14.7 hours.
【0027】(比較例4)2,2,6,6−テトラメチ
ル−4−アセトキシピペリジン−1−オキシルをを添加
しないで、実施例8と同様にIP−100を測定した。
その結果0.1時間以内であった。Comparative Example 4 IP-100 was measured in the same manner as in Example 8 without adding 2,2,6,6-tetramethyl-4-acetoxypiperidine-1-oxyl.
The result was within 0.1 hour.
【0028】(比較例5)EDTA−2Naを添加しな
いで、実施例8と同様にIP−100を測定した。その
結果1.2時間であった。Comparative Example 5 IP-100 was measured in the same manner as in Example 8 without adding EDTA-2Na. The result was 1.2 hours.
【発明の効果】本発明の重合防止方法は、複合型重合抑
制剤を共存させる事により、(メタ)アクリル酸の精製
時、貯蔵もしくは輸送時およびエステル化反応時に問題
となる重合物発生を防止する事ができる。さらに重合防
止剤の添加量を削減することが可能となり、着色のより
少ない高品質の製品を得る事ができる、非常に有用な重
合防止方法である。The polymerization prevention method of the present invention prevents the generation of a polymer which becomes a problem during the purification, storage or transportation of (meth) acrylic acid and during the esterification reaction by coexisting with a complex type polymerization inhibitor. You can do it. This is a very useful method for preventing polymerization, in which the amount of polymerization inhibitor added can be reduced, and a high-quality product with less coloring can be obtained.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特公 昭51−15001(JP,B1) 特公 昭45−1054(JP,B1) 中国特許出願公開1052847(CN,A) (58)調査した分野(Int.Cl.7,DB名) C08F 2/00 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-B-51-15001 (JP, B1) JP-B-45-1054 (JP, B1) Chinese Patent Application Publication 1052847 (CN, A) (58) Fields surveyed (Int.Cl. 7 , DB name) C08F 2/00
Claims (4)
くは輸送時またはエステル化反応時に、重合防止剤とし
て、酸性条件下におけるFe(III)との錯体の安定度定
数が10以上のキレート化剤と、下記一般式(1)で表
されるN−オキシル化合物を共存させることを特徴とす
る(メタ)アクリル酸の重合防止方法。 【化1】 ただし一般式(1)において、Rは水素原子、アルキル
基、アシル基を示す。1. A chelating agent in which the stability constant of a complex with Fe (III) under acidic conditions is 10 or more as a polymerization inhibitor during purification, storage or transport, or esterification reaction of (meth) acrylic acid. A method for preventing polymerization of (meth) acrylic acid, comprising coexisting an agent and an N-oxyl compound represented by the following general formula (1). Embedded image However, in the general formula (1), R represents a hydrogen atom, an alkyl group, or an acyl group.
またはそのアルカリ金属塩、ジエチレントリアミン五酢
酸またはそのアルカリ金属塩、トランス−1,2−シク
ロヘキサンジアミン四酢酸またはそのアルカリ金属塩で
ある請求項1記載の(メタ)アクリル酸の重合防止方
法。2. The method according to claim 1, wherein the chelating agent is ethylenediaminetetraacetic acid or an alkali metal salt thereof, diethylenetriaminepentaacetic acid or an alkali metal salt thereof, trans-1,2-cyclohexanediaminetetraacetic acid or an alkali metal salt thereof. Method for preventing polymerization of (meth) acrylic acid.
素数1〜6のアルキル基、炭素数1〜8のアシル基で表
されるN−オキシル化合物である請求項1または2記載
の(メ夕)アクリル酸の重合防止方法。3. A general formula (1) in the R is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, according to claim 1 or 2, wherein the N- oxyl compound represented by the acyl group having 1 to 8 carbon atoms (Meiyu) A method for preventing polymerization of acrylic acid.
テトラメチル−4−アセトキシピペリジン−1−オキシ
ル、2,2,6,6−テトラメチル−4−ヒドロキシピ
ペリジン−1−オキシルまたは2,2,6,6−テトラ
メチル−4−メトキシピペリジン−1−オキシルである
請求項3記載の(メタ)アクリル酸の重合防止方法。4. The method according to claim 1, wherein the N-oxyl compound is 2,2,6,6-
Tetramethyl-4-acetoxypiperidine-1-oxyl, 2,2,6,6-tetramethyl-4-hydroxypiperidine-1-oxyl or 2,2,6,6-tetramethyl-4-methoxypiperidine-1-oxyl The method for preventing polymerization of (meth) acrylic acid according to claim 3, which is oxyl.
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JP15451892A JP3197947B2 (en) | 1992-05-21 | 1992-05-21 | Method for preventing polymerization of (meth) acrylic acid |
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JP15451892A JP3197947B2 (en) | 1992-05-21 | 1992-05-21 | Method for preventing polymerization of (meth) acrylic acid |
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JPH05320205A JPH05320205A (en) | 1993-12-03 |
JP3197947B2 true JP3197947B2 (en) | 2001-08-13 |
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JP15451892A Expired - Lifetime JP3197947B2 (en) | 1992-05-21 | 1992-05-21 | Method for preventing polymerization of (meth) acrylic acid |
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DE19531649A1 (en) * | 1995-08-29 | 1997-03-06 | Basf Ag | Dowel compound for chemical fastening technology |
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WO2000003965A1 (en) | 1998-07-14 | 2000-01-27 | Ciba Specialty Chemicals Holding Inc. | Derivatives of 1-oxyl-4-hydroxy- or 4-amino-2,2,6,6-tetramethylpiperidine as polymerization inhibitors for (meth)acrylate monomers |
FR2814741B1 (en) * | 2000-09-29 | 2004-02-27 | Atofina | PROCESS FOR THE STABILIZATION OF ACRYLIC MONOMERS |
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JP5260826B2 (en) * | 2005-12-12 | 2013-08-14 | 東ソー株式会社 | Method for producing high purity fluorine-containing (meth) acrylic acid ester |
CN101351449A (en) | 2005-12-27 | 2009-01-21 | 株式会社Adeka | Nitroxyl compound, and polymerization inhibitor and polymerization inhibitor composition using same |
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- 1992-05-21 JP JP15451892A patent/JP3197947B2/en not_active Expired - Lifetime
Cited By (2)
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---|---|---|---|---|
JP2011162787A (en) * | 2010-02-11 | 2011-08-25 | Hilti Ag | Resin mortar suitable for construction purpose, especially for chemical anchoring |
US12098070B2 (en) | 2019-04-02 | 2024-09-24 | Ecolab Usa Inc. | Pure chlorine dioxide generation system with reduced acid usage |
Also Published As
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JPH05320205A (en) | 1993-12-03 |
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