JPH0475937B2 - - Google Patents
Info
- Publication number
- JPH0475937B2 JPH0475937B2 JP7615585A JP7615585A JPH0475937B2 JP H0475937 B2 JPH0475937 B2 JP H0475937B2 JP 7615585 A JP7615585 A JP 7615585A JP 7615585 A JP7615585 A JP 7615585A JP H0475937 B2 JPH0475937 B2 JP H0475937B2
- Authority
- JP
- Japan
- Prior art keywords
- polyacrylamide
- polymer
- weight
- polymer compound
- solution
- 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.)
- Expired
Links
- 229920000642 polymer Polymers 0.000 claims description 21
- 229920002401 polyacrylamide Polymers 0.000 claims description 15
- 150000001875 compounds Chemical class 0.000 claims description 13
- 230000000087 stabilizing effect Effects 0.000 claims description 7
- PDQAZBWRQCGBEV-UHFFFAOYSA-N Ethylenethiourea Chemical compound S=C1NCCN1 PDQAZBWRQCGBEV-UHFFFAOYSA-N 0.000 claims description 5
- -1 alkali metal salt Chemical class 0.000 claims description 3
- 238000000034 method Methods 0.000 claims description 3
- 238000002156 mixing Methods 0.000 claims description 3
- 239000002253 acid Substances 0.000 claims description 2
- 229910052783 alkali metal Inorganic materials 0.000 claims description 2
- 150000003863 ammonium salts Chemical class 0.000 claims description 2
- 239000000243 solution Substances 0.000 description 10
- UMGDCJDMYOKAJW-UHFFFAOYSA-N thiourea Chemical compound NC(N)=S UMGDCJDMYOKAJW-UHFFFAOYSA-N 0.000 description 10
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 6
- 239000003795 chemical substances by application Substances 0.000 description 6
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Natural products NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- YXIWHUQXZSMYRE-UHFFFAOYSA-N 1,3-benzothiazole-2-thiol Chemical compound C1=CC=C2SC(S)=NC2=C1 YXIWHUQXZSMYRE-UHFFFAOYSA-N 0.000 description 4
- 239000007864 aqueous solution Substances 0.000 description 4
- 230000006866 deterioration Effects 0.000 description 4
- 238000005259 measurement Methods 0.000 description 4
- 150000003839 salts Chemical class 0.000 description 4
- 239000003381 stabilizer Substances 0.000 description 4
- HRPVXLWXLXDGHG-UHFFFAOYSA-N Acrylamide Chemical compound NC(=O)C=C HRPVXLWXLXDGHG-UHFFFAOYSA-N 0.000 description 3
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 3
- KCXVZYZYPLLWCC-UHFFFAOYSA-N EDTA Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(O)=O)CC(O)=O KCXVZYZYPLLWCC-UHFFFAOYSA-N 0.000 description 3
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 3
- 239000001110 calcium chloride Substances 0.000 description 3
- 229910001628 calcium chloride Inorganic materials 0.000 description 3
- 229920001577 copolymer Polymers 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 229910052760 oxygen Inorganic materials 0.000 description 3
- 239000001301 oxygen Substances 0.000 description 3
- 239000011780 sodium chloride Substances 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 2
- 230000007062 hydrolysis Effects 0.000 description 2
- 238000006460 hydrolysis reaction Methods 0.000 description 2
- 239000000178 monomer Substances 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 239000011734 sodium Substances 0.000 description 2
- 229910001428 transition metal ion Inorganic materials 0.000 description 2
- PQUXFUBNSYCQAL-UHFFFAOYSA-N 1-(2,3-difluorophenyl)ethanone Chemical compound CC(=O)C1=CC=CC(F)=C1F PQUXFUBNSYCQAL-UHFFFAOYSA-N 0.000 description 1
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 description 1
- JKNCOURZONDCGV-UHFFFAOYSA-N 2-(dimethylamino)ethyl 2-methylprop-2-enoate Chemical compound CN(C)CCOC(=O)C(C)=C JKNCOURZONDCGV-UHFFFAOYSA-N 0.000 description 1
- 229920000536 2-Acrylamido-2-methylpropane sulfonic acid Polymers 0.000 description 1
- XHZPRMZZQOIPDS-UHFFFAOYSA-N 2-Methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid Chemical compound OS(=O)(=O)CC(C)(C)NC(=O)C=C XHZPRMZZQOIPDS-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- KGIGUEBEKRSTEW-UHFFFAOYSA-N 2-vinylpyridine Chemical compound C=CC1=CC=CC=N1 KGIGUEBEKRSTEW-UHFFFAOYSA-N 0.000 description 1
- NLHHRLWOUZZQLW-UHFFFAOYSA-N Acrylonitrile Chemical compound C=CC#N NLHHRLWOUZZQLW-UHFFFAOYSA-N 0.000 description 1
- CERQOIWHTDAKMF-UHFFFAOYSA-N Methacrylic acid Chemical compound CC(=C)C(O)=O CERQOIWHTDAKMF-UHFFFAOYSA-N 0.000 description 1
- 239000006096 absorbing agent Substances 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 125000005907 alkyl ester group Chemical group 0.000 description 1
- 125000003368 amide group Chemical group 0.000 description 1
- 230000001580 bacterial effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000007334 copolymerization reaction Methods 0.000 description 1
- 230000003292 diminished effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000008398 formation water Substances 0.000 description 1
- 125000000524 functional group Chemical group 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- FQPSGWSUVKBHSU-UHFFFAOYSA-N methacrylamide Chemical compound CC(=C)C(N)=O FQPSGWSUVKBHSU-UHFFFAOYSA-N 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000007348 radical reaction Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000013535 sea water Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 229940047670 sodium acrylate Drugs 0.000 description 1
- FWFUWXVFYKCSQA-UHFFFAOYSA-M sodium;2-methyl-2-(prop-2-enoylamino)propane-1-sulfonate Chemical compound [Na+].[O-]S(=O)(=O)CC(C)(C)NC(=O)C=C FWFUWXVFYKCSQA-UHFFFAOYSA-M 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 229910052723 transition metal Inorganic materials 0.000 description 1
Landscapes
- Compositions Of Macromolecular Compounds (AREA)
Description
本発明は、ポリアクリルアミド系高分子化合物
溶液の安定化法に関する。
ポリアクリルアミド系高分子化合物は、一般に
重合が容易で、比較的ゆるやかな条件で極めて高
い分子量物が得られる。このポリアクリルアミド
系高分子化合物の溶液物性を利用して水処理剤、
土壌改質剤、繊維加工剤、油水分離剤、石油回収
用薬剤など多枝にわたる分野に実用化されてい
る。一方、欠点として分解を起こし易い点があ
る。例えば、ポリアクリルアミド水溶液を室温に
て放置しておくと、比較的短期間のうちに水溶液
調製時に有していた粘性を有さなくなることがあ
る。この現象は高温時や溶液中にFe2+や、Co2+
の遷移金属塩が存在する場合顕著であり、はなは
だしい場合には水の粘性と変わらなくなつてしま
う場合がある。
以上のような問題点の解決をすべき種々の検討
がなされている。たとえば米国特許第3337356号
および同第3493539号では、紫外線吸収剤を用い
て、劣化を防止している。
一方、ポリアクリルアミド系化合物の高分子粘
性挙動を利用した分野として、石油回収用薬剤が
ある。ところが、高温の油層中に長期間存在する
ため、前記ポリマーの劣化が問題となる。この場
合の高分子化合物水溶液の粘性低下は、水中の溶
存酸素やFe2+、Co2+の遷移金属イオンの関与す
るラジカル反応によるものと考えられている。こ
のことからNa2やNaHSO3、あるいはチオ尿素等
の添加により劣化の抑制ができることは知られて
いる。（米国特許第3235523号、同第3234163号参
照）
これとは別に、酸素の存在下で劣化抑制作用を
呈するものに、ホルムアルデヒドや種々のアルコ
ールがある。（Journal of Petroleum
technology，Aug.1981，P1513〜参照）この他
に、含Ｓ・Ｎ化合物（例えば２−メルカプトベン
ゾチアゾールや２−メルカプトベンゾチアゾー
ル）などの安定剤の効果も知られている。（特公
昭58−47414号、特公昭44−26645号および特開昭
55−65696号参照）
これら従来技術は、その安定化作用という面で
はまだ十分ではなく、たとえ安定化作用があつた
としても、安定剤をポリマーに対して大量に添加
しなければならないことや、Fe2+や、Co2+のよ
うな遷移金属イオンに対して、その効果は十分で
はなかつた。
本発明者は、これら従来技術の問題点を解消す
べく、鋭意研究の結果、本発明に到達したもので
ある。
ポリアクリルアミド系高分子化合物溶液に、イ
チオ尿素、エチレンチオ尿素、又はNN−ジエチ
ルチオ尿素、及びロエチレンジアミンテトラ酢酸
（以下、EDTA）、そのアルカリ金属塩、又はそ
のアンモニウム塩を配合することを特徴とするポ
リアクリルアミド系高分子化合物溶液の安定化法
を提供するものである。
本発明の特徴とするところは、安定剤としてイ
チオ尿素、エチレンチオ尿素、又はNN−ジエチ
ルチオ尿素、及びロEDTA、そのNa，Ｋ、又は
NH4塩を使用することにより熱による安定化効
果を極めて高いものとした。
本発明でいうポリアクリルアミド系高分子化合
物とは、アクリルアミド重合体、アクリルアミド
部分を含む共重合体あるいは、これらの混合物を
いう。共重合体を構成する単量体としては、メタ
アクリルアミド、（メタ）アクリル酸（塩）、アク
リロニトリル、２−アクリルアミド−２−メチル
プロパンスルホン酸（塩）、ジ−メチルアミノエ
チルメタクリレート、アクリル酸低級アルキルエ
ステル、ビニルピリジンなどの親水性単量体であ
る。また、共重合反応によつたものに限らず、た
とえば、アクリルアミド重合体中のアミド基の50
モル％以下を加水分解したり、メチロール化また
はマンニツヒ化するなど高分子反応により他の官
能基を導入したものも包含する。本発明におい
て、ポリアクリルアミド系高分子化合物溶液濃度
は約0.0001〜20重量％水溶液、好ましくは0.001
〜５重量％である。
本発明における安定化剤の使用は、ポリアクリ
ルアミド系高分子化合物100重量部に対して0.1〜
20重量部である。0.1重量部以下では安定化の効
果が少なく、20重量部以上では、経済的効果が薄
れる。また、チオ尿素系と−EDTA系の比率は、
特に限定はないがEDTA系の量が50％以下の方
が効果的である。
ポリマー溶液に使用する水は、主として海水や
地層水等の比較的塩分濃度の高い水が利用され、
必要に応じて不溶物濾過や、バクテリアの殺菌
剤、防蝕剤等を添加することができる。
次に、本発明を実施例により具体的に説明す
る。
（以下の実施例で測定するスクリーン・フアクタ
ーは高分子化合物水溶液の粘性を示す指標の一つ
で、これは実際の油層中を流れる粘性と相関する
ものである。スクリーン・フアクターは、約30ml
の流体容積を持ち、５枚の0.25インチ径の
100meshステンレススチール製金網からなるスク
リーン粘度計を用いて、ポリマー水溶液とその溶
媒との通過時間の比で示される。測定にあたつて
は各ポリマー溶液を70℃にて恒温槽に保存し、経
日毎の測定は、ポリマー溶液の測定温度を25℃と
した。なお、溶存酸素の除去は実施しなかつた。）
実施例 １
分子量約1000万のアクリルアミド重合体
500ppm塩化ナトリウム３％および塩化カルシウ
ム0.1％からなる水溶液において、チオ尿素単独、
EDTA4Na単独、チオ尿素／EDTA4Na＝3/1お
よび1/1配合比のものを10ppm添加溶解し、前記
実験条件下で測定した。その結果を表−１に示し
た。
実施例 ２
分子量約700万の部分加水分解率20モル％のア
クリルアミド重合体500ppm、塩化ナトリウム３
％および塩化カルシウム0.1％からなる水溶液に
おいて、エチレンチオ尿素・EDTA2Na、エチ
レンチオ尿素／EDTA2Na＝1/1および3/1配合
比のものを10ppm添加溶解し、前記実験条件下で
測定した。その結果を表−２に示した。
実施例 ３
アクリルアミド80重量部アクリル酸ナトリウム
10重量部、２−アクリルアミド−２−メチルプロ
パンスルホン酸ナトリウム10重量部からなる分子
量約500万の共重合体700ppm、塩化ナトリウム３
％および塩化カルシウム0.1％からなる水溶液に
おいて、NN−ジエチルチオ尿素、EDTA3Na、
NN′−ジエチルチオ尿素／EDTA3Na＝3/1およ
び1/1配合比のものを10ppm添加溶解し、前記実
験条件下で測定した。その結果を表−３に示し
た。
The present invention relates to a method for stabilizing a polyacrylamide-based polymer compound solution. Polyacrylamide-based polymer compounds are generally easy to polymerize, and extremely high molecular weight products can be obtained under relatively mild conditions. Utilizing the solution properties of this polyacrylamide-based polymer compound, water treatment agents,
It has been put into practical use in a wide variety of fields, including soil conditioners, fiber processing agents, oil-water separation agents, and oil recovery agents. On the other hand, the drawback is that it tends to decompose. For example, if an aqueous polyacrylamide solution is left at room temperature, it may lose the viscosity it had when it was prepared within a relatively short period of time. This phenomenon occurs at high temperatures or when Fe 2+ and Co 2+
This is noticeable when transition metal salts of Various studies have been made to solve the above problems. For example, in US Pat. No. 3,337,356 and US Pat. No. 3,493,539, UV absorbers are used to prevent deterioration. On the other hand, oil recovery agents are a field that utilizes the polymer viscosity behavior of polyacrylamide compounds. However, since the polymer remains in the high-temperature oil layer for a long period of time, deterioration of the polymer becomes a problem. The decrease in viscosity of the aqueous polymer solution in this case is thought to be due to a radical reaction involving dissolved oxygen and transition metal ions such as Fe 2+ and Co 2+ in the water. From this, it is known that deterioration can be suppressed by adding Na 2 , NaHSO 3 , thiourea, or the like. (See US Pat. Nos. 3,235,523 and 3,234,163) In addition, formaldehyde and various alcohols exhibit a deterioration inhibiting effect in the presence of oxygen. (Journal of Petroleum
Technology, Aug. 1981, P1513~) In addition, the effects of stabilizers such as S/N-containing compounds (for example, 2-mercaptobenzothiazole and 2-mercaptobenzothiazole) are also known. (Special Publication No. 58-47414, Special Publication No. 44-26645 and
(Refer to No. 55-65696) These conventional techniques are not yet sufficient in terms of their stabilizing effect; even if they had a stabilizing effect, a large amount of stabilizer had to be added to the polymer; The effect was not sufficient for transition metal ions such as Fe 2+ and Co 2+ . The present inventor has arrived at the present invention as a result of intensive research in order to solve the problems of these conventional techniques. A polyacrylamide-based polymer compound solution containing ithiourea, ethylenethiourea, or NN-diethylthiourea, and loethylenediaminetetraacetic acid (hereinafter referred to as EDTA), an alkali metal salt thereof, or an ammonium salt thereof. The present invention provides a method for stabilizing an acrylamide-based polymer compound solution. The present invention is characterized in that thiourea, ethylenethiourea, or NN-diethylthiourea are used as stabilizers, and EDTA, its Na, K, or
By using NH 4 salt, the stabilizing effect due to heat was made extremely high. The polyacrylamide-based polymer compound as used in the present invention refers to an acrylamide polymer, a copolymer containing an acrylamide moiety, or a mixture thereof. Monomers constituting the copolymer include methacrylamide, (meth)acrylic acid (salt), acrylonitrile, 2-acrylamido-2-methylpropanesulfonic acid (salt), di-methylaminoethyl methacrylate, and lower acrylic acid. Hydrophilic monomers such as alkyl esters and vinyl pyridine. In addition, it is not limited to those produced by copolymerization reactions, for example, 50% of amide groups in acrylamide polymers.
It also includes those into which other functional groups have been introduced by a polymer reaction such as hydrolysis of less than mol%, methylolation, or Mannichization. In the present invention, the polyacrylamide polymer compound solution concentration is about 0.0001 to 20% by weight aqueous solution, preferably 0.001% by weight.
~5% by weight. The use of the stabilizer in the present invention is from 0.1 to 100 parts by weight of the polyacrylamide polymer compound.
It is 20 parts by weight. If it is less than 0.1 part by weight, the stabilizing effect will be small, and if it is more than 20 parts by weight, the economic effect will be diminished. In addition, the ratio of thiourea type and -EDTA type is
Although there is no particular limitation, it is more effective if the amount of EDTA is 50% or less. The water used for the polymer solution is mainly water with relatively high salt concentration, such as seawater or geological formation water.
If necessary, insoluble matter filtration, bacterial sterilizers, anticorrosive agents, etc. can be added. Next, the present invention will be specifically explained using examples. (The screen factor measured in the following examples is one of the indicators that shows the viscosity of an aqueous solution of a polymer compound, and it correlates with the viscosity flowing in an actual oil layer.The screen factor is approximately 30 ml.
of fluid volume and five 0.25 inch diameter
Using a screen viscometer consisting of a 100 mesh stainless steel wire gauze, it is expressed as the ratio of the transit time between the polymer aqueous solution and its solvent. For measurements, each polymer solution was stored in a constant temperature bath at 70°C, and the measurement temperature of the polymer solution was set at 25°C for daily measurements. Note that dissolved oxygen was not removed. ) Example 1 Acrylamide polymer with a molecular weight of approximately 10 million
In an aqueous solution consisting of 500 ppm sodium chloride 3% and calcium chloride 0.1%, thiourea alone,
10 ppm of EDTA4Na alone, thiourea/EDTA4Na = 3/1 and 1/1 blending ratios were added and dissolved and measured under the above experimental conditions. The results are shown in Table-1. Example 2 500 ppm of acrylamide polymer with a molecular weight of about 7 million and a partial hydrolysis rate of 20 mol%, 3 sodium chloride
% and 0.1% calcium chloride, 10 ppm of ethylene thiourea/EDTA2Na and ethylene thiourea/EDTA2Na with blending ratios of 1/1 and 3/1 were added and dissolved, and measurements were made under the experimental conditions described above. The results are shown in Table-2. Example 3 Acrylamide 80 parts by weight Sodium acrylate
10 parts by weight, 700 ppm of a copolymer with a molecular weight of approximately 5 million consisting of 10 parts by weight of sodium 2-acrylamido-2-methylpropanesulfonate, 3 parts by weight of sodium chloride
% and calcium chloride 0.1%, NN-diethylthiourea, EDTA3Na,
NN'-diethylthiourea/EDTA3Na=3/1 and 1/1 were added and dissolved at 10 ppm and measured under the experimental conditions described above. The results are shown in Table 3.
【表】【table】
【表】【table】
Claims (1)
イチオ尿素、エチレンチオ尿素、又はNN−ジエ
チルチオ尿素、及びロエチレンジアミンテトラ酢
酸、そのアルカリ金属塩、又はそのアンモニウム
塩を配合することを特徴とするポリアクリルアミ
ド系高分子化合物溶液の安定化法。1 Into the polyacrylamide polymer compound solution,
1. A method for stabilizing a polyacrylamide-based polymer compound solution, which comprises blending ithiourea, ethylenethiourea, or NN-diethylthiourea, and loethylenediaminetetraacetic acid, an alkali metal salt thereof, or an ammonium salt thereof.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7615585A JPS61233027A (en) | 1985-04-09 | 1985-04-09 | Stabilization of water-soluble polymeric compound solution |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7615585A JPS61233027A (en) | 1985-04-09 | 1985-04-09 | Stabilization of water-soluble polymeric compound solution |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61233027A JPS61233027A (en) | 1986-10-17 |
| JPH0475937B2 true JPH0475937B2 (en) | 1992-12-02 |
Family
ID=13597143
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7615585A Granted JPS61233027A (en) | 1985-04-09 | 1985-04-09 | Stabilization of water-soluble polymeric compound solution |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61233027A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6346600B1 (en) | 1999-04-22 | 2002-02-12 | Nippon Shokubai Co., Ltd. | Vinylpyrrolidone polymer and its stabilization and preservation processes |
-
1985
- 1985-04-09 JP JP7615585A patent/JPS61233027A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61233027A (en) | 1986-10-17 |
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